JP7786212B2 - Light-adjusting sheet - Google Patents

Description

The present invention relates to a light-control sheet.

A light-controlling sheet includes a first transparent electrode layer, a second transparent electrode layer, and a light-controlling layer located between the first and second transparent electrode layers. In one example of a light-controlling sheet, the light-controlling layer includes a transparent polymer layer having a plurality of voids and a liquid crystal composition that fills the voids. In this light-controlling sheet, for example, when no voltage is applied to the light-controlling layer, the light-controlling layer is opaque, whereas when a voltage is applied to the light-controlling layer, the light-controlling layer is transparent. When the light-controlling layer is opaque, it is difficult to see objects through the light-controlling layer. For this reason, light-controlling sheets are being considered for use in partitions and windows that separate spaces requiring privacy from the outside (see, for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 2021-67785

The state of a light-controlling sheet can be switched between transparent and opaque by simply switching between applying and not applying a voltage to the light-controlling layer. This means that the state of the light-controlling sheet can be changed in a shorter time than, for example, opening and closing a fabric curtain. For this reason, light-controlling sheets are being considered for use in environments where privacy can be instantly created, such as medical institutions. As the range of environments in which light-controlling sheets can be used expands, there is a new demand for light-controlling sheets to be able to contribute to increasing the safety of the environments in which they are used.

A light-controlling sheet that solves the above problems includes a first transparent electrode layer, a second transparent electrode layer, a light-controlling layer located between the first transparent electrode layer and the second transparent electrode layer, a first transparent support layer located on the opposite side of the first transparent electrode layer from the light-controlling layer, and an antiviral layer located on the opposite side of the first transparent support layer from the first transparent electrode layer and containing an antiviral agent. With this light-controlling sheet, the antiviral agent contained in the antiviral layer suppresses the proliferation of viruses in the light-controlling sheet.

The above-mentioned light-controlling sheet may further include an alignment layer sandwiched between the first transparent electrode layer and the light-controlling layer, the first alignment layer being configured to increase the haze of the light-controlling layer by applying a voltage to the first transparent electrode layer. The light-controlling layer may include a resin layer positioned between the first transparent electrode layer and the second transparent electrode layer and having voids dispersed therein, and a liquid crystal composition containing liquid crystal molecules and filling the voids. The light-controlling layer may also include a first high-density portion in which the density of the liquid crystal composition per unit thickness is high, and a low-density portion in which the density of the liquid crystal composition per unit thickness is lower than that of the first high-density portion, and the first high-density portion may be in contact with the first alignment layer.

With the above-mentioned light-controlling sheet, the density of the liquid crystal composition is high in areas that are close to the alignment layer, making it possible to increase the number of liquid crystal molecules that are aligned by the alignment control force of the alignment layer. This makes it possible to increase the transparency of the light-controlling sheet when no potential difference is present between the first transparent electrode layer and the second transparent electrode layer.

The above-mentioned light-modulating sheet may further include a covering layer located between the first transparent support layer and the antiviral layer, wherein the first transparent support layer includes a supporting surface that supports the first transparent electrode layer and a protected surface that is the surface opposite the supporting surface, and the first transparent electrode layer includes first electrode elements and second electrode elements, the first electrode elements and the second electrode elements being separate layered bodies aligned along the supporting surface and electrically insulated from each other by grooves extending in a direction along the supporting surface, the thickness direction of the first transparent electrode layer being the depth direction of the grooves, the grooves penetrating the first transparent support layer and the first transparent electrode layer in the depth direction, and having openings in the protected surface, the openings being covered by the covering layer.

With the above-mentioned light-adjusting sheet, the light transmittance of the area where the first electrode element is located and the area where the second electrode element is located can be changed by applying a voltage signal to only one of the first and second electrode elements, or by applying different voltage signals to the first and second electrode elements. Therefore, it is possible to switch between a state where there is no difference in light transmittance between the areas where these electrode elements are located without applying a voltage signal to both the first and second electrode elements, and a state where there is a difference in light transmittance between the areas where each electrode element is located, as described above, thereby improving the design of the light-adjusting sheet.

In the above-mentioned light-modulating sheet, the first transparent support layer includes a support surface that supports the first transparent electrode layer, and the first transparent electrode layer includes first electrode elements and second electrode elements, the first electrode elements and the second electrode elements being separate layered bodies aligned along the support surface and electrically insulated from each other by grooves extending along the support surface, the depth direction of the grooves being the thickness direction of the first transparent electrode layer, and the grooves having a depth that penetrates the first transparent electrode layer but does not penetrate the first transparent support layer.

With the above-described light-controlling sheet, the light transmittance of the region where the first electrode element is located and the region where the second electrode element is located can be changed by applying a voltage signal to only one of the first electrode element and the second electrode element, or by applying different voltage signals to the first electrode element and the second electrode element. This makes it possible to switch between a state in which there is no difference in light transmittance between the regions where these electrode elements are located without applying a voltage signal to both the first electrode element and the second electrode element, and a state in which there is a difference in light transmittance between the regions where each electrode element is located, as described above, thereby improving the design of the light-controlling sheet. Furthermore, because the grooves have a depth that penetrates the first transparent electrode layer but does not penetrate the first transparent electrode layer, light scattering by the grooves is suppressed on the surface of the first transparent support layer opposite the support surface. As a result, the grooves are less noticeable when the light-controlling sheet is viewed from the first transparent electrode layer side, at least from a position facing the opposite surface. This improves the aesthetic appearance of the light-controlling sheet.

In the above-mentioned light-modulating sheet, the first transparent support layer includes a support surface that supports the first transparent electrode layer, and the first transparent electrode layer includes a first electrode element and a second electrode element, the first electrode element and the second electrode element being separate layer bodies aligned along the support surface and electrically insulated from each other by a groove extending along the support surface, the first electrode element having a narrowed portion sandwiched between the grooves, and the width of the narrowed portion may be 1 mm or more.

With the above-described light-controlling sheet, the light transmittance of the region where the first electrode element is located and the region where the second electrode element is located can be changed by applying a voltage signal to only one of the first electrode element and the second electrode element, or by applying different voltage signals to the first electrode element and the second electrode element. Therefore, by changing the state of application of the voltage signal to these regions, it is possible to make a pattern appear on the light-controlling sheet, improving the design of the light-controlling sheet. Furthermore, because the width of the constriction portion provided in the first electrode element is 1 mm or more, peeling of the first transparent electrode layer or the first transparent support layer is unlikely to occur during the groove formation process or after groove formation. Furthermore, conductivity within the same electrode element can be ensured at the constriction portion. This prevents poor conductivity due to increased resistance at the constriction portion and allows for appropriate control of the light transmittance of the first electrode element and the second electrode element. Therefore, patterns can be clearly displayed on the light-controlling sheet, improving the design of the light-controlling sheet.

According to the present invention, it is possible to suppress the proliferation of viruses on light-control sheets.

1 is a cross-sectional view showing the structure of a light-adjusting device including a light-adjusting sheet according to a first embodiment. FIG. 2 is a cross-sectional view showing the structure of an antiviral film provided in the light control device shown in FIG. FIG. 10 is a cross-sectional view showing the structure of a light control device according to a second embodiment together with a drive unit. 2 is a cross-sectional view schematically showing an example of the structure of a light-controlling sheet included in the light-controlling device shown in FIG. 1 . FIG. 1. FIG. 4 is a cross-sectional view schematically showing another example of the structure of the light-controlling sheet provided in the light-controlling device shown in FIG. 10 is an SEM image of the cross-sectional structure of the light-modulating sheet of Test Example 1-1. 10 is an SEM image of the cross-sectional structure of the light-modulating sheet of Test Example 1-2. 10 is an SEM image of the cross-sectional structure of the light-modulating sheet of Test Example 1-3. 10 is an SEM image of the cross-sectional structure of the light-modulating sheet of Test Example 1-4. 10 is an SEM image of the cross-sectional structure of the light-modulating sheet of Test Example 1-5. 10 is an SEM image of the cross-sectional structure of the light-modulating sheet of Test Example 1-6. 10 is an SEM image of the cross-sectional structure of the light-modulating sheet of Test Example 1-7. 10 is an SEM image of the cross-sectional structure of the light-modulating sheet of Test Example 1-8. 10 is an SEM image of the cross-sectional structure of the light-modulating sheet of Test Example 1-9. 10 is an SEM image of the cross-sectional structure of the light-modulating sheet of Test Example 1-10. 10 is an SEM image of the cross-sectional structure of the light-modulating sheet of Test Example 1-11. 10 is an SEM image of the cross-sectional structure of the light-modulating sheet of Test Example 1-12. 10 is an SEM image of the cross-sectional structure of the light-modulating sheet of Test Example 1-13. FIG. 10 is a plan view showing the structure of a light controlling sheet in a third embodiment. FIG. 20 is a cross-sectional view showing the structure taken along line II of FIG. 19. FIG. 20 is a cross-sectional view showing a first example of the structure taken along line II-II in FIG. 19 . FIG. 20 is a cross-sectional view showing a second example of the structure taken along line II-II in FIG. 19 . FIG. 20 is a cross-sectional view showing a third example of the structure taken along line II-II in FIG. 19 . 10A and 10B are schematic diagrams illustrating a step included in the manufacturing method of the light controlling sheet according to the third embodiment. 10A and 10B are schematic diagrams illustrating a step included in the manufacturing method of the light controlling sheet according to the third embodiment. 10A and 10B are schematic diagrams illustrating a step included in the manufacturing method of the light controlling sheet according to the third embodiment. 10A and 10B are schematic diagrams illustrating a step included in the manufacturing method of the light controlling sheet according to the third embodiment. FIG. 11 is a plan view showing the structure of a light controlling sheet in a non-driven state in a third embodiment. FIG. 10 is a cross-sectional view showing the structure of a light controlling sheet in a modified example. FIG. 10 is a plan view showing the structure of a light controlling sheet in a modified example. FIG. 10 is a plan view showing the structure of a normal-type light controlling sheet in a fourth embodiment. FIG. 2 is a cross-sectional view showing the structure of the light controlling sheet of the same embodiment. FIG. 2 is a cross-sectional view showing the structure of the light controlling sheet of the same embodiment. FIG. 2 is an enlarged view of the cross-sectional structure of the light controlling sheet of the embodiment. 10 is an SEM image showing the cross-sectional structure of the light controlling sheet of the same embodiment. 3 is a schematic diagram illustrating one step included in the manufacturing method of the light controlling sheet of the same embodiment. FIG. FIG. 2 is a plan view showing the structure of a light controlling sheet in a non-driven state in the same embodiment. FIG. 10 is a plan view showing the structure of a light controlling sheet in a driven state in a modified example. FIG. 10 is a cross-sectional view showing the structure of a light controlling sheet in a modified example. FIG. 13 is a plan view showing the structure of a normal-type light controlling sheet in a fifth embodiment. 41 is a cross-sectional view taken along line VV of FIG. 40. 41 is a cross-sectional view taken along line VI-VI of FIG. 40. FIG. 41 is an enlarged plan view showing a part of the light controlling sheet shown in FIG. 40. FIG. 41 is an enlarged plan view showing a part of the light controlling sheet shown in FIG. 40. FIG. 41 is an enlarged plan view showing a part of the light controlling sheet shown in FIG. 40. 3A to 3C are diagrams schematically showing a method for manufacturing the light controlling sheet of the same embodiment. FIG. 2 is a plan view showing the structure of a light controlling sheet in a non-driven state in the same embodiment. FIG. 13 is a cross-sectional view showing the structure of a light controlling sheet according to a sixth embodiment. FIG. 10 is a plan view showing the structure of a modified light controlling sheet. FIG. 10 is a plan view showing the structure of a reverse-type light controlling sheet according to a modified example. FIG. 10 is a cross-sectional view showing the structure of a modified light controlling sheet. FIG. 10 is a cross-sectional view showing the structure of a modified light controlling sheet. FIG. 10 is a cross-sectional view showing the structure of a modified light controlling sheet. FIG. 10 is a front view showing the structure of a modified light controlling sheet. FIG. 10 is a front view showing the structure of a modified light controlling sheet. FIG. 2 is a plan view showing the shape of a measurement sample for measuring a resistance value. 10 is a table showing resistance values of test examples. 10 is a table showing effective voltages in test examples. 1 is a table showing the peel strength of test examples. 1 is a graph showing the relationship between the peel strength of a test piece and the peel strength per unit length.

[First embodiment]
A first embodiment of a light controlling sheet will be described with reference to FIGS. 1 and 2. FIG.

[Light control device]
A light control device including a light control sheet will be described with reference to FIG.
As shown in FIG. 1 , the light control device 10 includes a light control unit 11 including a reverse-type light control sheet 21 , and a drive unit 12 .

The light-controlling sheet 21 includes a light-controlling layer 31, a first alignment layer 32, a second alignment layer 33, a first transparent electrode layer 34, and a second transparent electrode layer 35. In the light-controlling sheet 21, the first alignment layer 32 and the second alignment layer 33 sandwich the light-controlling layer 31 in the thickness direction of the light-controlling layer 31. The first transparent electrode layer 34 and the second transparent electrode layer 35 sandwich the pair of alignment layers 32, 33 in the thickness direction of the light-controlling layer 31. The light-controlling sheet 21 further includes a first transparent substrate 36 that supports the first transparent electrode layer 34, and a second transparent substrate 37 that supports the second transparent electrode layer 35. The first transparent substrate 36 is an example of a first transparent support layer.

The dimming unit 11 includes a first electrode 22A attached to a portion of the first transparent electrode layer 34 and a second electrode 22B attached to a portion of the second transparent electrode layer 35. The dimming unit 11 further includes a first wiring 23A connected to the first electrode 22A and a second wiring 23B connected to the second electrode 22B. The first electrode 22A is connected to the drive unit 12 by the first wiring 23A, and the second electrode 22B is connected to the drive unit 12 by the second wiring 23B.

The light-controlling layer 31 comprises a transparent resin layer and a liquid crystal composition. The resin layer has voids into which the liquid crystal composition is filled. The voids in the resin layer are filled with the liquid crystal composition. The liquid crystal composition contains liquid crystal molecules. The liquid crystal molecules are negative-type liquid crystal molecules with negative dielectric anisotropy. Examples of liquid crystal molecules include those selected from the group consisting of Schiff bases, azos, azoxys, biphenyls, terphenyls, benzoates, tolans, pyrimidines, cyclohexanecarboxylic acid esters, phenylcyclohexanes, and dioxanes.

The liquid crystal composition is held in one of the following types: a polymer network type, a polymer dispersion type, and a capsule type. The polymer network type has a transparent polymer network with a three-dimensional mesh structure, and holds the liquid crystal composition in the interconnected voids of the mesh. The polymer network is an example of a resin layer. The polymer dispersion type has a large number of isolated voids in a resin layer, and holds the liquid crystal composition in the voids dispersed in the polymer layer. The capsule type holds a capsule-shaped liquid crystal composition in a resin layer. In addition to the liquid crystal molecules described above, the liquid crystal composition may also contain monomers for forming a resin layer, dichroic dyes, etc.

The materials used to form the first alignment layer 32 and the second alignment layer 33 are organic compounds, inorganic compounds, and mixtures thereof. Examples of organic compounds include polyimide, polyamide, polyvinyl alcohol, and cyanide compounds. Examples of inorganic compounds include silicon oxide and zirconium oxide. The material used to form the alignment layers 32 and 33 may also be silicone. Silicone is a compound that has both inorganic and organic portions. The thickness of each alignment layer 32 and 33 is, for example, 0.02 μm or more and 0.5 μm or less.

The first alignment layer 32 and the second alignment layer 33 are, for example, vertical alignment layers. The vertical alignment layer aligns the long axis direction of the liquid crystal molecules so that it is perpendicular to the surface opposite the surface in contact with the first transparent electrode layer 34 and the surface opposite the surface in contact with the second transparent electrode layer 35.

The first transparent electrode layer 34 and the second transparent electrode layer 35 are optically transparent, allowing visible light to pass through. The optical transparency of the first transparent electrode layer 34 allows for visual recognition of objects through the light-controlling sheet 21. The optical transparency of the second transparent electrode layer 35, like the optical transparency of the first transparent electrode layer 34, allows for visual recognition of objects through the light-controlling sheet 21. The thickness of each transparent electrode layer 34, 35 may be, for example, 0.005 μm or more and 0.1 μm or less. This makes it possible to reduce cracks when the light-controlling sheet 21 is flexed while ensuring proper operation.

The material for forming each transparent electrode layer 34, 35 may be, for example, any one selected from the group consisting of indium tin oxide, fluorine-doped tin oxide, tin oxide, zinc oxide, carbon nanotubes, and poly(3,4-ethylenedioxythiophene).

The material forming each transparent substrate 36, 37 may be a synthetic resin or an inorganic compound. Examples of synthetic resins include polyester, polyacrylate, polycarbonate, and polyolefin. Examples of polyesters include polyethylene terephthalate and polyethylene naphthalate. Examples of polyacrylates include polymethyl methacrylate. Examples of inorganic compounds include silicon dioxide, silicon oxynitride, and silicon nitride. The thickness of each transparent substrate 36, 37 is, for example, 16 μm or more and 250 μm or less. Having a thickness of 16 μm or more for the transparent substrate 36, 37 prevents difficulties in processing and applying the light-controlling sheet 21. Having a thickness of 250 μm or less for the transparent substrate 36, 37 prevents difficulties in manufacturing the light-controlling sheet 21 using a roll-to-roll process.

Each electrode 22A, 22B is, for example, a flexible printed circuit (FPC). The FPC includes a support layer, a conductor portion, and a protective layer. The conductor portion is sandwiched between the support layer and the protective layer. The support layer and the protective layer are formed from an insulating synthetic resin. The support layer and the protective layer are formed from, for example, polyimide. The conductor portion is formed from, for example, a thin metal film. The material that forms the thin metal film may be, for example, copper. Each electrode 22A, 22B is not limited to an FPC, and may also be, for example, a metal tape.

Note that each electrode 22A, 22B is attached to each transparent electrode layer 34, 35 by a conductive adhesive layer (not shown). In the portions of each electrode 22A, 22B connected to the conductive adhesive layer, the conductor portion is exposed from the protective layer or support layer.

The conductive adhesive layer may be formed from, for example, an anisotropic conductive film (ACF), an anisotropic conductive paste (ACP), an isotropic conductive film (ICF), or an isotropic conductive paste (ICP). From the perspective of ease of handling during the manufacturing process of the dimming device 10, it is preferable that the conductive adhesive layer be an anisotropic conductive film.

Each wiring 23A, 23B is formed, for example, from a metal wire and an insulating layer covering the metal wire. The wire is formed, for example, from copper.

The driver 12 applies an AC voltage between the first transparent electrode layer 34 and the second transparent electrode layer 35. The driver 12 preferably applies an AC voltage having a rectangular waveform between the pair of transparent electrode layers 34, 35. However, the driver 12 may also apply an AC voltage having a shape other than a rectangular waveform between the pair of transparent electrode layers 34, 35. For example, the driver 12 may apply an AC voltage having a sine wave between the pair of transparent electrode layers 34, 35.

The light-controlling layer 31 changes the orientation of the liquid crystal molecules in response to changes in the voltage generated between the two transparent electrode layers 34, 35. The change in orientation of the liquid crystal molecules alters the degree of scattering, absorption, and transmission of visible light entering the light-controlling layer 31. The reverse-type light-controlling sheet 21 has a relatively high haze when the light-controlling sheet 21 is energized, i.e., when a potential difference exists between the first transparent electrode layer 34 and the second transparent electrode layer 35. The reverse-type light-controlling sheet 21 has a relatively low haze when the light-controlling sheet 21 is not energized, i.e., when no potential difference exists between the first transparent electrode layer 34 and the second transparent electrode layer 35. For example, the reverse-type light-controlling sheet 21 is opaque when the light-controlling sheet 21 is energized and transparent when the light-controlling sheet 21 is not energized.

The light-controlling sheet 21 is attached to windows in moving objects such as vehicles and aircraft. It can also be attached to windows in various buildings such as homes, train stations, and airports, partitions installed in offices, medical institutions, and nursing homes, show windows installed in stores, and screens for projecting images. The light-controlling sheet 21 may be flat or curved.

The light-modulating sheet 21 further includes a first antiviral film 41 and a second antiviral film 42. The first antiviral film 41 is located on the surface of the first transparent substrate 36 opposite the surface on which the first transparent electrode layer 34 is located. The second antiviral film 42 is located on the surface of the second transparent substrate 37 opposite the surface on which the second transparent electrode layer 35 is located.

In the example shown in FIG. 1, the light-adjusting sheet 21 includes a first antiviral film 41 and a second antiviral film 42, but the light-adjusting sheet 21 may include only one of the first antiviral film 41 and the second antiviral film 42. Incidentally, if the light-adjusting sheet 21 includes the first antiviral film 41 and the second antiviral film 42, the virus-reducing effect of the light-adjusting sheet 21 can be enhanced and the difference in appearance between the front and back of the light-adjusting sheet 21 can be reduced.

Figure 2 shows the cross-sectional structure of the first antiviral film 41. Note that while the second antiviral film 42 is attached to a different object from the object to which the first antiviral film 41 is attached, it shares a cross-sectional structure with the first antiviral film 41. Therefore, the following description will focus on the cross-sectional structure of the first antiviral film 41, but will omit a description of the cross-sectional structure of the second antiviral film 42.

As shown in FIG. 2, the first antiviral film 41 includes a base layer 41A, an antiviral layer 41B, and an adhesive layer 41C. The base layer 41A has a pair of opposing surfaces, with the antiviral layer 41B located on one surface and the adhesive layer 41C located on the other. The base layer 41A is formed from, for example, polyethylene phthalate or polyolefin. The base layer 41A has a thickness of, for example, 80 μm or more and 120 μm or less.

The adhesive layer 41C may have high adhesion to the target, but may not be removable from the target, or may be removable but not re-attachable. Alternatively, the adhesive layer 41C may have low adhesion to the target, but may be capable of being repeatedly removed from and attached to the target. An adhesive layer 41C with high adhesion is formed, for example, from an olefin-based adhesive. An adhesive layer 41C with low adhesion is formed, for example, from a polyethylene terephthalate-based adhesive or an olefin-based adhesive. The adhesive layer 41C has a thickness of, for example, several μm. The antiviral film 41 is attached to the first transparent substrate 36, which is the target, by the adhesive layer 41C.

The antiviral layer 41B contains a synthetic resin and an antiviral agent. The antiviral agent contained in the antiviral layer 41B suppresses the proliferation of viruses in the light-adjusting sheet 21. Therefore, the light-adjusting sheet 21 can contribute to increasing the safety of the space defined by the light-adjusting sheet 21.

The synthetic resin may be, for example, a melamine-based resin, a urethane-based resin, or an acrylic-based resin. The synthetic resin may be an ultraviolet-curable resin. The antiviral agent may be, for example, an organic antiviral agent. The organic antiviral agent may be, for example, bis(2-pyridylthio)zinc 1,1'-dioxide, 2-(4-thiazolyl)benzimidazole, or an organic nitrogen-sulfur-halogen compound.

The antiviral agent may be composed of, for example, a porous substance and metal ions supported on the porous substance. The porous substance may be, for example, zeolite, apatite, zirconia, etc. The metal ions may be silver ions, copper ions, zinc ions, etc. The antiviral agent may have antibacterial function in addition to antiviral function.

The metal ions supported by the porous material have a positive charge. Therefore, when an AC voltage is applied between the pair of transparent electrode layers 34, 35, the metal ions may migrate along the thickness direction of the first antiviral film 41.

As described above, the antiviral layer 41B containing the antiviral agent is separated from the transparent substrates 36, 37 by the base layer 41A and adhesive layer 41C. This prevents metal ions from migrating outside the antiviral films 41, 42 and inside the antiviral films 41, 42 in the light-controlling sheet 21 in response to the application of an AC voltage.

When the light-controlling sheet 21 includes the antiviral films 41, 42, the increase in capacitance in the light-controlling sheet 21 is suppressed compared to when the transparent substrates 36, 37 contain an antiviral agent. Furthermore, because the antiviral layer 41B of the antiviral films 41, 42 contains an antiviral agent, the antiviral agent is prevented from migrating further inward into the light-controlling sheet 21 than the antiviral films 41, 42, compared to when the adhesive layer contains an antiviral agent. Furthermore, when the light-controlling sheet 21 includes the antiviral films 41, 42, the uneven distribution of metal ions within the light-controlling layer 31 is suppressed compared to when the light-controlling layer 31 contains an antiviral agent, thereby suppressing deterioration of the light-controlling layer 31. Even when the antiviral agent is an organic antiviral agent, the antiviral films 41, 42 suppress the reaction between the liquid crystal molecules LCM contained in the light-controlling layer 31 and the antiviral agent, thereby suppressing deterioration of the light-controlling layer 31.

When forming the antiviral layer 41B, for example, a coating liquid containing the above-mentioned synthetic resin, antiviral agent, and solvent is prepared. The coating liquid is applied to one surface of the base material layer 41A, and then cured to form the antiviral layer 41B.

To further enhance the privacy protection function of the light-adjusting sheet 21, it is preferable that the antiviral films 41, 42 have a haze of 30% or more. To further enhance the transparency of the light-adjusting sheet 21 when no voltage is applied, it is preferable that the antiviral films 41, 42 have a haze of less than 30%.

As described above, according to the first embodiment of the light controlling sheet, the following effects can be obtained.
(1-1) The antiviral agent contained in the antiviral layer 41B suppresses the proliferation of viruses in the light-controlling sheet 21. Therefore, the light-controlling sheet 21 can contribute to increasing the safety of the space defined by the light-controlling sheet 21.

(1-2) By providing the light-adjusting sheet 21 with the first antiviral film 41 and the second antiviral film 42, the light-adjusting sheet 21's virus-reducing effect can be enhanced and the difference in appearance between the front and back of the light-adjusting sheet 21 can be reduced.

(1-3) In the antiviral film 41, the antiviral layer 41B is separated from the transparent substrates 36 and 37 by the base layer 41A and the adhesive layer 41C. Therefore, even if the antiviral layer 41B contains metal ions, the metal ions are prevented from migrating inward from the antiviral films 41 and 42 in response to the application of an AC voltage.

[Modification of the first embodiment]
The first embodiment described above can be modified as follows.
[Anti-viral film]
The light controlling sheet 21 may include only the antiviral layer of the above-described antiviral films 41, 42. That is, the light controlling sheet 21 may include an antiviral layer located on each of the transparent substrates 36, 37. Alternatively, the light controlling sheet 21 may include an antiviral layer on only one of the first transparent substrate 36 and the second transparent substrate 37. The antiviral layer is formed by applying the above-described coating liquid to each of the transparent substrates 36, 37.

In this case, the antiviral light-adjusting sheet 21 can be made thinner and lighter than when it is equipped with antiviral films 41, 42. Furthermore, because there is only one layer located outside the transparent substrates 36, 37, it is also possible to improve optical properties such as light transmittance and haze.

- The light-adjusting sheet 21 may further include the antiviral films 41, 42 described above in addition to the antiviral layers located on the transparent substrates 36, 37. In this case, the light-adjusting sheet 21 includes both the antiviral films 41, 42 and the antiviral layer, thereby enhancing the antiviral properties of the light-adjusting sheet 21.

The light-modulating sheet 21 may include a pair of antiviral layers and a pair of antiviral films, or may include only one antiviral layer and one antiviral film. When the light-modulating sheet 21 includes only one antiviral layer and one antiviral film, the antiviral layer may be located on one of the first transparent substrate 36 and the second transparent substrate 37, and the antiviral film may be located on the other. Alternatively, when the light-modulating sheet 21 includes only one antiviral layer and one antiviral film, the antiviral layer may be located on either the first transparent substrate 36 or the second transparent substrate 37, and the antiviral film may be located on the antiviral layer.

The light-controlling sheet 21 may also include a pair of antiviral layers and one antiviral film. Alternatively, the light-controlling sheet 21 may include one antiviral layer and a pair of antiviral films.

The dimming body may include antiviral films 41, 42, not limited to the above-described dimming sheet 21. The dimming body includes a dimming sheet 21 and a transparent support that supports the dimming sheet 21. The dimming body may include only one transparent support, or two. When the dimming body includes one transparent support, the transparent support is adhered to the first transparent substrate 36 or the second transparent substrate 37 of the dimming sheet 21 by a transparent adhesive layer. When the dimming body includes two transparent supports, one transparent support is adhered to the first transparent substrate 36 by a transparent adhesive layer, and the other transparent support is adhered to the second transparent substrate 37 by a transparent adhesive layer. The dimming body may have antiviral films on both of a pair of surfaces that face each other in the thickness direction of the dimming body, or may have an antiviral film on only one of the pair of surfaces.

- The photochromic element may have only the antiviral layer of the antiviral films 41, 42. In other words, the photochromic element may have an antiviral layer located on at least one of a pair of opposing surfaces in the thickness direction of the photochromic element.

The photochromic element may include both an antiviral layer and an antiviral film. In this case, the photochromic element may include a pair of antiviral layers and a pair of antiviral films, or may include only one antiviral layer and one antiviral film. When the photochromic element includes only one antiviral layer and one antiviral film, the antiviral layer may be located on one of a pair of opposing surfaces in the thickness direction of the photochromic element, and the antiviral film may be located on the other. Alternatively, the antiviral layer may be located on one of a pair of opposing surfaces in the thickness direction of the photochromic element, and the antiviral film may be located on the antiviral layer.

The photochromic element may also include a pair of antiviral layers and one antiviral film. Alternatively, the photochromic element may include one antiviral layer and a pair of antiviral films.

- The transparent support provided in the light control body may be provided with an antiviral layer on the surface that is bonded to the light control sheet 21 by the adhesive layer.

[Light control sheet]
The light-controlling sheet may be of the normal type. In this case, the light-controlling sheet does not include alignment layers 32 and 33, and the light-controlling layer 31 contains positive-type liquid crystal molecules with positive dielectric anisotropy. A normal-type light-controlling sheet has a relatively low haze when the light-controlling sheet is energized, and a relatively high haze when the light-controlling sheet is not energized. For example, a normal-type light-controlling sheet is transparent when the light-controlling sheet is energized, and opaque when the light-controlling sheet is not energized.

- The form of the light-controlling sheet is not limited to a system that switches between transparent and opaque by controlling the orientation of liquid crystal molecules, but may also be an electrochromic system that reversibly promotes a redox reaction depending on the magnitude of the electric field applied to the light-controlling sheet, and changes the light absorption rate as the redox reaction progresses.

Second Embodiment
A second embodiment of the light-controlling sheet will be described with reference to Figures 3 to 18. The light-controlling sheet of the second embodiment has a different structure of the light-controlling layer compared to the light-controlling sheet of the first embodiment. Therefore, these differences will be described in detail below, while detailed description of the commonalities between the light-controlling sheet of the second embodiment and the light-controlling sheet of the first embodiment will be omitted. The light-controlling device, light-controlling sheet, and examples will be described in order below.

[Light control device]
The light control device will be described with reference to Fig. 3. For convenience of illustration, the antiviral film provided in the light control device is omitted from Fig. 3. The light control sheet of the second embodiment can include the antiviral film provided in the light control sheet of the first embodiment, and the antiviral film or antiviral layer described in the modified example of the first embodiment.

As shown in FIG. 3, the light control device 10, like the light control device 10 of the first embodiment, comprises a light control unit 11 including a reverse-type light control sheet 21, and a drive unit 12. The light control layer 31 comprises a transparent resin layer and a liquid crystal composition. The resin layer has voids into which the liquid crystal composition is filled. The liquid crystal composition fills the voids in the resin layer. The liquid crystal composition contains liquid crystal molecules. Any of the liquid crystal molecules listed in the first embodiment can be used as the liquid crystal molecules.

The thickness of the light-controlling layer 31 is preferably at least twice the smallest gap size and no more than 10 μm, for example, at least 2 μm and no more than 10 μm. Furthermore, the thickness of the light-controlling layer 31 is more preferably at least 3.0 μm and no more than 8.0 μm. By making the thickness of the light-controlling layer 31 at least twice the gap size, it is easy to create at least two regions with relatively different densities within the light-controlling layer 31, as described below. Furthermore, by making the thickness of the light-controlling layer 31 no more than 10 μm, it is easy to properly separate the liquid crystal molecules from the transparent resin layer when a coating liquid containing liquid crystal molecules is exposed to light during the manufacture of the light-controlling sheet 21.

[Light control sheet]
The structure of the light controlling sheet 21 will be described in more detail with reference to FIGS.
4 and 5 schematically show the cross-sectional structure of the light-controlling sheet 21. For ease of illustration, the transparent substrates 36 and 37 are omitted from FIGS. 4 and 5 . For ease of illustrating the structure of the light-controlling layer 31, the ratio of the thickness of the light-controlling layer 31 to the thicknesses of the alignment layers 32 and 33 and the transparent electrode layers 34 and 35 is shown to be larger than the actual ratio. Furthermore, FIGS. 4 and 5 show the state of the light-controlling layer 31 when no potential difference is generated between the pair of transparent electrode layers 34 and 35.

As shown in FIG. 4, the light-controlling sheet 21 comprises a first transparent electrode layer 34, a second transparent electrode layer 35, a light-controlling layer 31, and a first alignment layer 32, to which a voltage is applied. The light-controlling layer 31 comprises a resin layer 31P and a liquid crystal composition 31LC. The resin layer 31P is located between the first transparent electrode layer 34 and the second transparent electrode layer 35, and voids 31D are dispersed in the resin layer 31P. The liquid crystal composition 31LC contains liquid crystal molecules LCM and fills the voids 31D. The first alignment layer 32 is sandwiched between the first transparent electrode layer 34 and the light-controlling layer 31. The first alignment layer 32 is configured to increase the haze of the light-controlling layer 31 upon application of a voltage. The light-controlling layer 31 comprises a first high-density portion 31H1 having a high density of the liquid crystal composition 31LC per unit thickness, and a low-density portion 31L having a low density of the liquid crystal composition 31LC per unit thickness. The first high-density portion 31H1 is in contact with the first alignment layer 32.

In other words, the density of the liquid crystal composition 31LC is lowest in the middle of the light-controlling layer 31 in the thickness direction. The middle of the light-controlling layer 31 in the thickness direction refers to a portion of the light-controlling layer 31 closer to the center of the light-controlling layer 31 than the opposing surfaces in the thickness direction. The density of the liquid crystal composition 31LC per unit thickness in each portion of the light-controlling layer 31 is calculated by dividing the volume of the liquid crystal composition 31LC contained in each portion by the thickness of each portion. It is preferable that the density of the liquid crystal composition 31LC be lowest in a portion of the light-controlling layer 31 including the center in the thickness direction. Because the light-controlling layer 31 is very thin, it is practically difficult to determine the volume of the liquid crystal composition 31LC contained in the light-controlling layer 31. Therefore, in the present disclosure, each density is calculated using the area of the liquid crystal composition 31LC determined from an SEM image of a cross section of the light-controlling layer 31 and the area of the light-controlling layer 31.

The first alignment layer 32 is, for example, a vertical alignment layer, and typically aligns the liquid crystal molecules LCM so that the long axes of the liquid crystal molecules LCM are perpendicular to the first transparent electrode layer 34. However, the first alignment layer 32 may also align the liquid crystal molecules LCM so that the long axes are tilted by several degrees from the vertical, within a range in which the long axes of the liquid crystal molecules LCM are determined to be substantially perpendicular to the first transparent electrode layer 34. Furthermore, the density of the liquid crystal composition 31LC in the first high-density portion 31H1 is higher than the density of the liquid crystal composition 31LC in the low-density portion 31L.

Because the density of the liquid crystal composition 31LC is high in regions at a short distance from the first alignment layer 32, it is possible to increase the amount of liquid crystal molecules LCM that are oriented by the alignment restriction force of the first alignment layer 32 among the multiple liquid crystal molecules LCM. As a result, the transparency of the light control sheet 21 can be increased when no potential difference is generated between the first transparent electrode layer 34 and the second transparent electrode layer 35.

The transparency of the light-adjusting sheet 21 can be expressed by the visible light transmittance of the light-adjusting sheet 21. The transparency of the light-adjusting sheet 21 can also be expressed by the haze of the light-adjusting sheet 21. Haze is calculated using a method in accordance with JIS K 7136:2000. The lower the haze value of the light-adjusting sheet 21, the more transparent the light-adjusting sheet 21 is, and the higher the haze value, the less transparent the light-adjusting sheet 21 is.

As described above, the light-controlling sheet 21 further includes a second alignment layer 33 located between the light-controlling layer 31 and the second transparent electrode layer 35 in the thickness direction of the light-controlling layer 31. The light-controlling layer 31 further includes a second high-density portion 31H2. The second high-density portion 31H2 is in contact with the second alignment layer 33 and has a density of the liquid crystal composition 31LC that is higher than the density of the liquid crystal composition 31LC in the low-density portion 31L. The low-density portion 31L is sandwiched between the first high-density portion 31H1 and the second high-density portion 31H2 in a cross section along the thickness direction of the light-controlling layer 31.

In the light-controlling layer 31, liquid crystal molecules LCM are aligned in the vicinity of a pair of surfaces that face each other in the thickness direction of the light-controlling layer 31 according to the alignment restricting force of the alignment layers 32 and 33. Therefore, when no potential difference is generated between the first transparent electrode layer 34 and the second transparent electrode layer 35, the light transmittance of the light-controlling sheet 21 can be further improved. In other words, the haze of the light-controlling sheet 21 can be reduced.

The photochromic layer 31 is composed of a first high-density portion 31H1, a second high-density portion 31H2, and a low-density portion 31L. In a cross section along the thickness direction of the photochromic layer 31, the density of the voids 31D per unit thickness is the value obtained by dividing the area of the voids 31D by the thickness of the photochromic layer 31. The density of the voids 31D per unit thickness in the first high-density portion 31H1 and the density of the voids 31D per unit thickness in the second high-density portion 31H2 are higher than the density of the voids 31D per unit thickness in the low-density portion 31L.

Therefore, the density of the liquid crystal composition 31LC in the first high density portion 31H1 and the density of the liquid crystal composition 31LC in the second high density portion 31H2 can be made higher than the density of the liquid crystal composition 31LC in the low density portion 31L.
The density of the voids 31D per unit thickness is calculated by dividing the sum of the areas of the voids 31D included in each portion by the thickness of each portion.

In the photochromic layer 31, for example, the thickness TH1 of the first high-density portion 31H1, the thickness TH2 of the second high-density portion 31H2, and the thickness TL of the low-density portion 31L are approximately equal to one another. That is, the thickness TH1 of the first high-density portion 31H1, the thickness TH2 of the second high-density portion 31H2, and the thickness TL of the low-density portion 31L are approximately one-third of the thickness T31 of the photochromic layer 31. The thickness TL of the low-density portion 31L may be thicker or thinner than the thicknesses TH1 and TH2 of the high-density portions 31H1 and 31H2. Furthermore, the thickness TH1 of the first high-density portion 31H1 may be equal to or different from the thickness of the second high-density portion 31H2.

In a cross section along the thickness direction of the light-controlling layer 31, it is preferable that the percentage ([SD/SL] x 100) of the sum of the areas (SD) of the voids 31D contained in the low-density portions 31L relative to the area (SL) of the low-density portions 31L be 10% or less. This reduces the proportion of liquid crystal composition 31LC held by the voids 31D in the low-density portions 31L, thereby preventing the liquid crystal molecules LCM contained in the low-density portions 31L from increasing the opacity of the light-controlling sheet 21 when no potential difference is present between the first transparent electrode layer 34 and the second transparent electrode layer 35.

Furthermore, it is preferable that the low-density portion 31L does not have any voids 31D. In other words, it is preferable that the low-density portion 31L does not contain the liquid crystal composition 31LC. This makes it easier for all of the liquid crystal molecules LCM contained in the light-controlling layer 31 to be aligned in accordance with the alignment restricting force of the alignment layers 32 and 33, thereby further reducing the haze of the light-controlling sheet 21 when no voltage difference is generated between the first transparent electrode layer 34 and the second transparent electrode layer 35.

As such, in the low-density portion 31L, the sum SD of the areas of the voids 31D relative to the area SL of the low-density portion 31L is preferably 10% or less, more preferably 5% or less, and most preferably 0%.

Furthermore, the voids 31D can be located within a range of 3.0 μm or less from the first alignment layer 32 and within a range of 3.0 μm or less from the second alignment layer 33 in a cross section along the thickness direction of the switchable layer 31. In other words, the thickness TH1 of the first high-density portion 31H1 can be 3.0 μm or less, and the thickness TH2 of the second high-density portion 31H2 can be 3.0 μm or less.

The range of the voids 31D relative to the first alignment layer 32 is the maximum distance between the voids 31D located closer to the first alignment layer 32 than the center of the switchable layer 31 in a cross section along the thickness direction of the switchable layer 31 and the surface of the first alignment layer 32 that contacts the switchable layer 31. The range of the voids 31D relative to the second alignment layer 33 is the maximum distance between the voids 31D located closer to the second alignment layer 33 than the center of the switchable layer 31 in a cross section along the thickness direction of the switchable layer 31 and the surface of the second alignment layer 33 that contacts the switchable layer 31.

In a cross section along the thickness direction of the light-controlling layer 31, the gaps 31D are located within a range of 3.0 μm or less from each alignment layer 32, 33, which increases the reliability with which the liquid crystal molecules LCM held in each gap 31D are aligned in accordance with the alignment restriction force.

It is preferable that each void 31D included in the first high-density portion 31H1 contacts the first alignment layer 32. It is also preferable that each void 31D included in the second high-density portion 31H2 contacts the second alignment layer 33. In other words, it is preferable that the multiple voids 31D provided in the photochromic layer 31 are composed of only one void layer along the interface between the first alignment layer 32 and the photochromic layer 31, and one void layer along the interface between the second alignment layer 33 and the photochromic layer 31.

Each void 31D included in the first high-density portion 31H1 and each void 31D included in the second high-density portion 31H2 can hold the liquid crystal composition 31LC in contact with the alignment layers 32, 33, making it easier for the alignment restricting force of the alignment layers 32, 33 to act on the entire liquid crystal composition 31LC held in each void 31D. This further enhances the transparency of the light-controlling sheet 21 when no potential difference is generated between the first transparent electrode layer 34 and the second transparent electrode layer 35.

On the other hand, the light-controlling sheet 21 of the present disclosure can also be defined by the thickness of the light-controlling layer 31 and the size of the voids 31D. That is, in the light-controlling sheet 21, the thickness T31 of the light-controlling layer 31 is 3.0 μm or more and 8.0 μm or less, and the size of the voids 31D is 1.0 μm or more and 2.5 μm or less.

Because the thickness of the light-controlling layer 31 is between 3.0 μm and 8.0 μm, the formation of voids 31D at positions away from the pair of opposing surfaces in the thickness direction of the light-controlling layer 31 is suppressed. Furthermore, because the size of the voids 31D is between 1.0 μm and 2.5 μm, the liquid crystal composition 31LC is retained near the alignment layers 32 and 33. This makes it possible to enhance the transparency of the light-controlling sheet 21 when no voltage difference is generated between the first transparent electrode layer 34 and the second transparent electrode layer 35.

In terms of the scattering properties of the light-adjusting sheet 21, it is preferable that the size of the voids 31D be 0.38 μm or more and 3.0 μm or less. By having the size of the voids 31D fall within the range of 0.38 μm or more and 3.0 μm or less, it is possible to achieve an appropriate level of scattering in the light-adjusting sheet 21. By having the size of the voids 31D be 0.38 μm or more, scattering properties, particularly in the visible range, are sufficiently ensured. By having the size of the voids 31D be 3.0 μm or less, the optical effect of the liquid crystal, i.e., the component of light that passes through the voids, is prevented from becoming greater than the component of light that is scattered, making it easier to achieve an appropriate light-adjusting effect.

If the void 31D has a circular shape in a cross section taken along the thickness direction of the light-adjusting sheet 21, the size of the void 31D is the diameter of the void 31D. If the void 31D has an elliptical shape in a cross section taken along the thickness direction of the light-adjusting sheet 21, the size of the void 31D is the major axis of the void 31D. If the void 31D has an irregular shape in a cross section taken along the thickness direction of the light-adjusting sheet 21, the size of the void 31D is the diameter of a circle circumscribing the void 31D.

In a cross section along the thickness direction of the light-controlling layer 31, the liquid crystal molecules LCM held at a smaller distance from each alignment layer 32, 33 are more likely to be oriented in accordance with the alignment restricting force of the alignment layers 32, 33. As described above, when the size of the gap 31D is 2.5 μm or less, the liquid crystal molecules LCM held in each gap 31D located in the high-density portions 31H1, 31H2 are more likely to be oriented in accordance with the alignment restricting force.

When forming the light-controlling sheet 21, first, transparent substrates 36, 37 on which transparent electrode layers 34, 35 are formed are prepared. Then, alignment layers 32, 33 are formed on each of the transparent electrode layers 34, 35. Next, a coating liquid is applied between the pair of alignment layers 32, 33. The coating liquid contains a polymerizable composition for forming a resin layer 31P and liquid crystal molecules LCM. The polymerizable composition is a monomer or oligomer that can be polymerized by irradiation with ultraviolet light. Then, ultraviolet light is irradiated onto the coating liquid through the transparent electrode layers 34, 35, thereby forming a resin layer 31P with voids 31D and retaining the liquid crystal molecules LCM within the voids 31D.

When the coating liquid hardens, the liquid crystal composition 31LC containing the liquid crystal molecules LCM is first separated from the polymerizable composition, and the liquid crystal composition 31LC is positioned in multiple locations within the polymerizable composition. Next, before the polymerizable composition hardens, the liquid crystal composition 31LC migrates toward the alignment layers 32 and 33. The polymerizable composition is then hardened to form a resin layer 31P having voids 31D surrounding the liquid crystal composition 31LC. Until the resin layer 31P is formed, the voids 31D formed in the resin layer 31P continue to expand as the separated liquid crystal compositions 31LC aggregate. In this regard, if the size of the voids 31D is 1.0 μm or greater, it is possible to reduce the likelihood that the polymerizable composition will harden before each void 31D migrates to the vicinity of the alignment layers 32 and 33. As a result, it is possible to reduce the number of voids 31D in the low-density portion 31L of the light-controlling layer 31.

4 is one example of a possible structure of the light-switching layer 31. The light-switching layer 31 may have a cross-sectional structure shown in FIG.
5, the light-controlling layer 31 includes one gap layer formed by a plurality of gaps 31D in contact with the first alignment layer 32, and one gap layer formed by a plurality of gaps 31D in contact with the second alignment layer 33. In each gap layer, a single gap 31D is arranged along the interface between the light-controlling layer 31 and each of the alignment layers 32 and 33.

The void layer in contact with the first alignment layer 32 includes at least one void 31D that is in contact with one of the voids 31D in the void layer in contact with the second alignment layer 33. All of the voids 31D included in the void layer in contact with the first alignment layer 32 may be in contact with one of the voids 31D included in the void layer in contact with the second alignment layer 33.

In the gap layer in contact with the first alignment layer 32, the surface in contact with the first alignment layer 32 is the first surface, and the surface opposite the first surface is the second surface. The second surface is a plane that includes the portion of the voids 31D contained in the gap layer that is the farthest from the first alignment layer 32. In the gap layer in contact with the second alignment layer 33, the surface that includes the second alignment layer 33 is the first surface, and the surface opposite the first surface is the second surface. The second surface is a plane that includes the portion of the voids 31D contained in the gap layer that is the farthest from the second alignment layer 33. It is preferable that the second surface of the gap layer in contact with the first alignment layer 32 and the second surface of the gap layer in contact with the second alignment layer 33 are the same surface.

The light-modulating sheet 21 includes a first high-density portion 31H1, a second high-density portion 31H2, and a low-density portion 31L. In the thickness direction of the light-modulating layer 31, the low-density portion 31L is sandwiched between the first high-density portion 31H1 and the second high-density portion 31H2. The low-density portion 31L includes a portion of the gap layer in contact with the first alignment layer 32 where no voids 31D are located, and also includes a portion of the gap layer in contact with the second alignment layer 33 where no voids 31D are located. Therefore, the density of the liquid crystal composition 31LC in the low-density portion 31L is lower than the density of the liquid crystal composition 31LC in the first high-density portion 31H1 and the density of the liquid crystal composition 31LC in the second high-density portion 31H2.

Also, in the example shown in Figure 5, the density of the liquid crystal composition 31LC in the light-controlling layer 31 is lowest at the middle of the thickness of the light-controlling layer 31.

[Test Example]
A test example will be described with reference to FIGS.
The light-modulating sheets of Test Examples 1-1 to 1-8 were obtained by the manufacturing method described below.
[Test Example 1-1]
A pair of PET substrates with ITO films formed thereon was prepared. The ITO film had a thickness of 30 nm, and the PET substrate had a thickness of 125 μm. A vertical alignment layer with a thickness of 100 nm was formed on each ITO film using a bar coater. Next, a coating liquid containing a polymerizable composition and liquid crystal molecules was applied to one of the vertical alignment layers. The other vertical alignment layer was then placed on the coating film, thereby sandwiching the coating film between the pair of vertical alignment layers. Ultraviolet light was irradiated onto the coating film from both sides in the thickness direction of the coating film through the PET substrate, ITO film, and vertical alignment layer.

One factor that influences the quality of light-adjusting sheets is the exposure process of the coating film, i.e., the light-adjusting layer, during the production of the light-adjusting sheet. More specifically, during the exposure process, the optimal exposure amount, or in other words, the optimal cumulative light amount, is determined taking into account various conditions such as the materials contained in the coating liquid and the thickness of the coating. Here, the cumulative light amount is calculated by multiplying the illuminance of the ultraviolet light irradiated by the exposure time of the ultraviolet light. Each test example described below describes a light-adjusting sheet obtained by appropriately changing the illuminance and exposure time to obtain the optimal cumulative light amount. Note that the thickness of the light-adjusting layer of all light-adjusting sheets shown in each test example is set to 7.0 μm.

In Test Example 1-1, the illuminance of the ultraviolet light was set to 10 mW/cm ² , and the coating film was irradiated with ultraviolet light so that the cumulative light amount was 600 mJ/cm ² .
[Test Example 1-2]
A light-controlling sheet of Test Example 1-2 was obtained in the same manner as in Test Example 1-1, except that the illuminance when irradiating the coating film with ultraviolet light was changed to 15 mW/cm ² in Test Example 1-1.

[Test Example 1-3]
A light-controlling sheet of Test Example 3 was obtained in the same manner as Test Example 1-1, except that the illuminance when irradiating the coating film with ultraviolet light was changed to 20 mW/cm ² in Test Example 1-1.

[Test Example 1-4]
A light-controlling sheet of Test Example 1-4 was obtained in the same manner as Test Example 1-1, except that the illuminance when irradiating the coating film with ultraviolet light was changed to 25 mW/cm ² in Test Example 1-1.

[Test Example 1-5]
A light-controlling sheet of Test Example 1-5 was obtained in the same manner as Test Example 1-1, except that the illuminance when irradiating the coating film with ultraviolet light was changed to 30 mW/cm ² in Test Example 1-1.

[Test Example 1-6]
A light-controlling sheet of Test Example 1-6 was obtained in the same manner as Test Example 1-1, except that the illuminance when irradiating the coating film with ultraviolet light was changed to 35 mW/cm ² in Test Example 1-1.

[Test Example 1-7]
A light-controlling sheet of Test Example 1-7 was obtained in the same manner as Test Example 1-1, except that the illuminance when irradiating the coating with ultraviolet light was changed to 40 mW/cm ² in Test Example 1-1.

[Test Example 1-8]
A light-controlling sheet of Test Example 1-8 was obtained in the same manner as Test Example 1-1, except that the illuminance when irradiating the coating with ultraviolet light was changed to 200 mW/cm ² in Test Example 1-1.

[Evaluation method]
[Gap size]
The size of the voids was determined by observing the cross section of the resin layer using a scanning electron microscope. To determine the size of the voids, first, the liquid crystal composition containing liquid crystal molecules was removed from the resin layer. A square test piece with a side length of 10 cm was cut out from each of the light-controlling sheets of Test Examples 1-1 to 1-8. Then, each test piece was immersed in isopropyl alcohol to remove the liquid crystal composition from the resin layer. It is possible to remove the liquid crystal composition from the test piece by immersing the test piece in an organic solvent that dissolves the liquid crystal composition but does not dissolve the resin layer.

Then, a scanning electron microscope was used to image the cross section of the test piece from which the liquid crystal composition had been removed. 30 rectangular regions were arbitrarily set on the cross section of the test piece. Images were then obtained for each region using the scanning electron microscope at a magnification of 1000x. The 30 rectangular regions were set so that the distance between adjacent rectangular regions was 1 mm or more.

Ten voids were randomly selected in each image, and the size of each void was measured. The maximum and minimum values of the void sizes for the 10 voids were set as the maximum and minimum void sizes for that image. The maximum and minimum void sizes for each image were calculated. The maximum of the maximum values found in the 30 images was set as the maximum void size for the test piece. In addition, the minimum of the minimum values found in the 30 images was set as the minimum void size for the test piece.

For gaps in the image that were circular, the diameter of the gap was set as the gap size. For gaps in the image that were elliptical, the major axis of the gap was set as the gap size. For gaps in the image that were irregularly shaped, the diameter of the circle circumscribing the gap was set as the gap size.

[Formation range]
In each of the images used to calculate the size of the voids, the boundary between the first alignment layer and the photochromic layer was used as a reference to calculate the formation range of the voids in the thickness direction of the photochromic layer. The maximum value of the formation ranges found in the 30 images was set as the void formation range for that test piece.

[Percentage of void area relative to low density portion area SL]
For each image used to calculate the size of the voids, the area SL of the low-density portion and the area of each void were calculated. Then, for each image, the percentage of the sum SD of the area of the voids relative to the area SL of the low-density portion ([SD/SL] x 100) was calculated. Then, for 30 images, the average value of the percentage of the sum of the area of the voids relative to the area of the low-density portion was calculated. This average value was set as the percentage of the sum of the area of the voids relative to the area of the low-density portion in each test piece. The area of each void was calculated based on the number of pixels located within the area partitioned by the void in each image.

[Hayes]
For each of the light-controlling sheets of Test Examples 1-1 to 1-8, the haze when opaque and the haze when transparent were calculated. The haze was calculated using a method conforming to JIS K 7136:2000. For each light-controlling sheet, a state in which no potential difference occurs between the pair of transparent electrode layers, i.e., a state in which no AC voltage is applied between the pair of transparent electrodes, was defined as transparent. In addition, a state in which an AC voltage is applied between the pair of transparent electrode layers and the haze of the light-controlling sheet is saturated was defined as opaque.

[Clarity]
The clarity when opaque was calculated for each of the light-controlling sheets of Test Examples 1-1 to 1-8. Clarity was calculated using the following formula (1), where, among the light transmitted through the light-controlling layer 31, the amount of straight light traveling straight along the optical axis of the parallel light LP incident on the light-controlling layer 31 is defined as light amount L _C , and the amount of narrow-angle scattered light at an angle of ±2.5° or less with respect to the optical axis of the parallel light LP is defined as light amount L _R. As with the calculation of haze, an AC voltage was applied between the pair of transparent electrode layers, and the opaque state was defined as a state in which the haze of the light-controlling sheet was saturated.
100×(L _C −L _R )/(L _C +L _R ) … Formula (1)

[Linear transmittance]
For each of the light-controlling sheets of Test Examples 1-1 to 1-8, the linear transmittance when opaque and the linear transmittance when transparent were calculated. For each light-controlling sheet, the state in which no potential difference occurs between the pair of transparent electrode layers, i.e., the state in which no AC voltage is applied between the pair of transparent electrodes, was defined as the transparent state. In addition, the state in which an AC voltage is applied between the pair of transparent electrode layers and the haze of the light-controlling sheet is saturated was defined as the opaque state.

[Evaluation results]
The results of photographing the cross section of each test piece are shown in Figures 6 to 13. The evaluation results are shown in Tables 1 and 2 below. Figures 6 to 13 show SEM images of the cross sections of the light-adjusting sheets of Test Examples 1-1 to 1-8, in order.

As shown in Figure 13, in the light-controlling sheet of Test Example 1-8, voids were found to be formed almost uniformly throughout the entire thickness of the light-controlling sheet. In other words, it was found that the light-controlling sheet did not have high-density areas where the density of liquid crystal molecules was relatively high and low-density areas where the density of liquid crystal molecules was relatively low.

In contrast, as shown in Figures 6 to 12, in the light-control sheets of Test Examples 1-1 to 1-7, high-density areas were formed in the areas in contact with each alignment layer, and low-density areas were formed between the two high-density areas in the thickness direction of the light-control sheet. In particular, the light-control sheet of Test Example 1-7 had voids in the low-density areas, while the light-control sheets of Test Examples 1-1 to 1-6 did not have voids in the low-density areas.

It was found that the haze values of the light-adjusting sheets of Test Examples 1-1 to 1-7 when transparent were significantly smaller than the haze value of the light-adjusting sheet of Test Example 1-8 when transparent. Therefore, it can be said that by having high-density and low-density sections in the light-adjusting sheet, the haze value when transparent was reduced, i.e., the transparency of the light-adjusting sheet 21 when transparent was improved.

As shown in Tables 1 and 2, the percentage of the sum SD of the void area relative to the area SL of the low-density portion was found to be 0% in Test Example 1-1, 0% in Test Example 1-2, and 0% in Test Example 1-3. Furthermore, the percentage of the sum SD of the void area relative to the area SL of the low-density portion was found to be 0% in Test Example 1-4, 0% in Test Example 1-5, 0% in Test Example 1-6, and 8% in Test Example 1-7. In contrast, the percentage of the sum SD of the void area relative to the area SL of the low-density portion was found to be 11% in Test Example 1-8.

The haze values of the light-controlling sheets of Test Examples 1-1 to 1-6 when transparent are even better than the haze value of the light-controlling sheet of Test Example 1-7 when transparent. Therefore, it can be said that the haze value when transparent is even better when the percentage of the sum of the void areas SD relative to the area SL of the low-density portions is 10% or less.

Furthermore, in the light-controlling sheets of Test Example 1-1 to Test Example 1-7, the minimum void size was found to be 1.1 μm or more and 1.4 μm or less, and was found to be 1.0 μm or more. In contrast, in the light-controlling sheet of Test Example 1-8, the minimum void size was found to be 0.8 μm, and was less than 1.0 μm. On the other hand, in the light-controlling sheets of Test Example 1-2 to Test Example 1-8, the maximum void size was found to be 1.5 μm or more and 2.4 μm or less, and was found to be 2.5 μm or less. In contrast, in the light-controlling sheet of Test Example 1-1, the maximum void size was found to be 2.7 μm, and was found to be greater than 2.5 μm.

In the light-controlling sheets of Test Examples 1-1 to 1-7, the minimum void size was 1.0 μm or more, so it can be said that the haze value was lower when transparent compared to the light-controlling sheet of Test Example 1-8, where the minimum void size was less than 1.0 μm. On the other hand, in the light-controlling sheets of Test Examples 1-2 to 1-5, the maximum void size was 2.5 μm or less, so it can be said that the haze value was even lower when transparent compared to the light-controlling sheet of Test Example 1-1, where the maximum void size was greater than 2.5 μm.

In addition, in Test Examples 1-1 to 1-5, it was found that voids were formed within a range of 3.0 μm from the alignment layer. On the other hand, in Test Examples 1-6, 1-7, and 1-8, it was found that voids were formed within a range of more than 3.0 μm from the alignment layer. Since Test Examples 1-1 to 1-5 had lower haze values when transparent than Test Examples 1-6 and 1-7, it can be said that in Test Examples 1-1 to 1-5, the formation of voids within a range of 3.0 μm from the alignment layer is one factor that lowers the haze values when transparent.

In Test Examples 1-1 to 1-8, the thickness of the photochromic layer was set constant, and the differences resulting from changing the exposure conditions were evaluated. In Test Examples 1-9 to 1-13, described below, the exposure conditions were set constant, and the differences resulting from changing the thickness of the photochromic layer were evaluated.

[Test Example 1-9]
In Test Example 1-9, a light-control layer having a thickness of 3.0 μm was formed by reducing the amount of coating liquid applied to the vertical alignment layer compared to Test Example 1-1. In all of the examples described below, the illuminance when irradiating the coating film with ultraviolet light was set to 20 mW/cm ² and the cumulative light amount was set to 600 mJ/cm ² .

[Test Example 1-10]
In Test Example 1-10, the light-controlling sheet of Test Example 1-10 was prepared in the same manner as Test Example 1-9, except that a light-controlling layer having a thickness of 7.0 μm was obtained by increasing the amount of coating liquid applied to the vertical alignment layer.

[Test Example 1-11]
In Test Example 1-11, the light-controlling sheet of Test Example 1-11 was prepared in the same manner as Test Example 1-9, except that a light-controlling layer having a thickness of 8.0 μm was obtained by increasing the amount of coating liquid applied to the vertical alignment layer.

[Test Example 1-12]
In Test Example 1-12, the light-controlling sheet of Test Example 1-12 was prepared in the same manner as Test Example 1-9, except that a light-controlling layer having a thickness of 10.0 μm was obtained by increasing the amount of coating liquid applied to the vertical alignment layer.

[Test Example 1-13]
In Test Example 1-13, the light-controlling sheet of Test Example 1-13 was prepared in the same manner as Test Example 1-9, except that a light-controlling layer having a thickness of 16.0 μm was obtained by increasing the amount of coating liquid applied to the vertical alignment layer.

[Evaluation method]
[image]
The cross sections of the light-adjusting sheets of Test Examples 1-9 to 1-13 were imaged using the same method as used to image the cross sections of the light-adjusting sheets of Test Examples 1-1 to 1-8.

[Gap size]
The size of the voids in the light-adjusting sheets of Test Examples 1-9 to 1-13 was calculated using the same method as that used to calculate the size of the voids in the light-adjusting sheets of Test Examples 1-1 to 1-8. This allowed the minimum and maximum values of the void size to be calculated for each light-adjusting sheet.

[Evaluation results]
The results of imaging the cross sections of the light-adjusting sheets of Test Examples 1-9 to 1-13 are shown in Figures 14 to 18. Figures 14 to 18 show SEM images of the cross sections of the light-adjusting sheets of Test Examples 1-9 to 1-13, in order.

As shown in Figures 14 to 16, when the thickness of the light-controlling layer was 3.0 μm or more and 8.0 μm or less, it was found that multiple voids were formed along the boundaries between each alignment layer and the light-controlling sheet. On the other hand, when the thickness of the light-controlling layer was 3.0 μm or more and 8.0 μm or less, it was found that no voids were formed in the center of the light-controlling layer in the thickness direction.

In contrast, as shown in Figure 17, when the thickness of the photochromic layer was 10.0 μm, it was observed that multiple voids were formed irregularly throughout the entire photochromic layer. In other words, when the thickness of the photochromic layer was 10 μm, it was observed that the photochromic layer did not have high-density or low-density areas. Furthermore, as shown in Figure 18, when the thickness of the photochromic layer was 16.0 μm, it was observed that multiple voids were formed in the center of the photochromic layer in the thickness direction, with a density similar to the density of voids at the boundaries between each alignment layer and the photochromic sheet. It was also observed that multiple voids were formed in the thickness direction of the photochromic layer between the voids located in the center and the voids located at the boundaries between the alignment layer and the photochromic layer.

It was confirmed that the minimum and maximum values of the void size in each light-controlling sheet were within the range of 1.0 μm or more and 2.5 μm or less.
As described above, according to the second embodiment of the light controlling sheet, the following effects can be obtained.

(2-1) Because the density of the liquid crystal composition 31LC is high in regions that are close to the alignment layers 32, 33, it is possible to increase the amount of liquid crystal molecules LCM that are aligned by the alignment restriction force of the alignment layers 32, 33 among the multiple liquid crystal molecules LCM. As a result, the transparency of the light control sheet 21 can be increased when no potential difference is generated between the first transparent electrode layer 34 and the second transparent electrode layer 35.

(2-2) Because the thickness T31 of the light-controlling layer 31 is 3.0 μm or more and 8.0 μm or less, the formation of voids 31D at positions away from a pair of opposing surfaces in the thickness direction of the light-controlling layer 31 is suppressed. Furthermore, because the size of the voids 31D is 1.0 μm or more and 2.5 μm or less, the liquid crystal composition 31LC is retained in the vicinity of the alignment layers 32, 33. This makes it possible to enhance the transparency of the light-controlling sheet 21 when no voltage difference is generated between the first transparent electrode layer 34 and the second transparent electrode layer 35.

(2-3) In the light-controlling layer 31, the liquid crystal molecules LCM are aligned in the vicinity of a pair of surfaces that face each other in the thickness direction of the light-controlling layer 31 in accordance with the alignment restricting force of the alignment layers 32 and 33. Therefore, when no potential difference is generated between the first transparent electrode layer 34 and the second transparent electrode layer 35, the transparency of the light-controlling sheet 21 can be further improved.

(2-4) Because the density of the voids 31D in each of the high-density portions 31H1 and 31H2 is higher than the density of the voids 31D in the low-density portion 31L, it is possible to make the density of the liquid crystal composition 31LC in each of the high-density portions 31H1 and 31H2 higher than the density of the liquid crystal composition 31LC in the low-density portion 31L.

(2-5) Each void 31D included in the first high-density portion 31H1 and each void 31D included in the second high-density portion 31H2 can hold the liquid crystal composition 31LC in the vicinity of the alignment layers 32, 33, making it easier for the alignment restriction force of the alignment layers 32, 33 to act on the entire liquid crystal composition 31LC held in each void 31D.

(2-6) Since the percentage of the total area SD of the voids 31D included in the low-density portion 31L relative to the area SL of the low-density portion 31L is 10% or less, it is possible to reduce the proportion of the liquid crystal composition 31LC held by the voids 31D in the low-density portion 31L.

(2-7) When the low-density portion 31L does not have the voids 31D, the proportion of liquid crystal molecules LCM contained in the light-controlling layer 31 that are oriented in accordance with the alignment restricting force of the alignment layers 32 and 33 is increased, thereby further increasing the transparency of the light-controlling sheet 21 when no voltage difference is generated between the first transparent electrode layer 34 and the second transparent electrode layer 35.

(2-8) In a cross section along the thickness direction of the light-controlling layer 31, the gaps 31D are located within a range of 3.0 μm or less from each alignment layer 32, 33, which increases the reliability with which the liquid crystal molecules LCM held in each gap 31D are aligned in accordance with the alignment restraining force.

[Modification of the second embodiment]
The second embodiment described above can be modified as follows.
[Alignment layer]
The light-controlling sheet 21 may include the first alignment layer 32 but may not include the second alignment layer 33. In this case, the light-controlling layer 31 may include the first high-density portion 31H1 and the low-density portion 31L, thereby achieving the effect equivalent to that described in (2-1) above.

- When the light-controlling sheet 21 has a first alignment layer 32 but does not have a second alignment layer 33, the density of the voids 31D in the first high-density portion 31H1 is higher than the density of the voids 31D in the low-density portion 31L, and the effects related to the first high-density portion 31H1 among those described above in (2-5) can be obtained.

[Light-controlling layer]
The light-controlling layer 31 may have the lowest density of the liquid crystal composition 31LC at the middle in the thickness direction of the light-controlling layer 31, but may not have high-density portions 31H1 and 31H2 in contact with the alignment layers 32 and 33. That is, the high-density portions may be located in portions of the light-controlling layer 31 closer to the alignment layers 32 and 33 than the middle in the thickness direction of the light-controlling layer 31, and at positions farther from the alignment layers 32 and 33. Even in this case, the density of the liquid crystal composition 31LC being lowest at the middle in the thickness direction of the light-controlling layer 31 can provide an effect equivalent to the above-described (2-1).

- When the density of the liquid crystal composition 31LC is lowest at the middle of the thickness direction of the light-controlling layer 31 and there are no high-density portions 31H1, 31H2 in contact with the alignment layers 32, 33, the void 31D may be located within 3.0 μm or less from the alignment layers 32, 33 in the cross section along the thickness direction of the light-controlling layer 31. In this case, it is possible to obtain effects similar to those described above in (2-1) and (2-8).

- In a light-controlling sheet 21 having a light-controlling layer 31 with high-density portions 31H1, 31H2 and low-density portions 31L, the thickness of the light-controlling layer 31 may be at least twice the smallest size of the voids 31D but less than 10 μm, and the size of the voids 31D may be at least 0.38 μm but not more than 3.0 μm. In this case, it is possible to obtain effects similar to those described above in (2-1) and (2-2).

- In a light-controlling sheet 21 having a light-controlling layer 31 in which the density of the liquid crystal composition 31LC is lowest at the middle in the thickness direction of the light-controlling layer 31, the thickness of the light-controlling layer 31 may be at least twice the smallest value of the size of the voids 31D but less than 10 μm, and the size of the voids 31D may be at least 0.38 μm but not more than 3.0 μm. In this case, it is possible to obtain effects similar to those described above in (2-1) and (2-2).

[Third embodiment]
A third embodiment of the light controlling sheet will be described with reference to FIGS.
[Light control sheet]
19 , the light controlling sheet 110 has a first surface 111F and a second surface 111R that is the surface opposite to the first surface 111F. When viewed from a position facing the first surface 111F, the light controlling sheet 110 has a driving region 120, a non-driving region 121, and a connection region 124.

The driving region 120 is an area where the driving electrode element 130, which is an electrode element to which a voltage signal is applied when the light controlling sheet 110 is driven, is located. The light transmittance of the driving region 120 changes depending on the state of application of the voltage signal to the driving electrode element 130. The driving electrode element 130 is an example of a first electrode element.

The non-driving region 121 includes a floating region 122, which is an area where floating electrode elements 131, which are electrode elements to which no voltage signal is applied when the light controlling sheet 110 is driven, are located, and a boundary region 123 that surrounds the floating region 122. The floating electrode elements 131 are an example of a second electrode element. The boundary region 123 is located between the driving region 120 and the floating region 122, and has a closed frame shape that surrounds the floating region 122. No electrode elements are located in the boundary region 123. Note that the width of the boundary region 123 is exaggerated in the drawings to make it easier to understand. The light transmittance of the non-driving region 121 does not change whether the light controlling sheet 110 is driven or not.

The floating areas 122 form a pattern, and by making the floating areas 122 visible, the pattern is displayed on the light-adjusting sheet 110. The pattern may be, for example, one or a combination of letters, numbers, symbols, figures, pictures, and patterns. The light-adjusting sheet 110 may have multiple floating areas 122 that are spaced apart from one another, i.e., multiple non-driven areas 121 that are spaced apart from one another.

The connection region 124 is a region where wiring for applying a voltage signal to the drive region 120 is connected. The connection region 124 includes a first connection region 124A and a second connection region 124B. A first terminal portion 135A is provided in the first connection region 124A, and a second terminal portion 135B is provided in the second connection region 124B. Each connection region 124A, 124B is adjacent to the drive region 120 and is located, for example, at the end of the light control sheet 110.

Figure 20 is a cross-sectional view taken along line I-I in Figure 19, showing the cross-sectional structure of the light-controlling sheet 110 in the drive region 120 and connection region 124. For ease of illustration, the antiviral film provided on the light-controlling sheet 110 is omitted from Figure 20. The light-controlling sheet 110 of the third embodiment can be provided with the antiviral film provided on the light-controlling sheet of the first embodiment, as well as the antiviral film or antiviral layer described in the modified example of the first embodiment.

As shown in FIG. 20, the light-controlling sheet 110 has a light-controlling layer 140, a first transparent electrode layer 141A, a second transparent electrode layer 141B, a first transparent support layer 142A, a second transparent support layer 142B, and a covering layer 145. The light-controlling layer 140 is sandwiched between the first transparent electrode layer 141A and the second transparent electrode layer 141B and is in contact with these transparent electrode layers 141A and 141B. The first transparent support layer 142A supports the first transparent electrode layer 141A on the side opposite the light-controlling layer 140 relative to the first transparent electrode layer 141A, and the second transparent support layer 142B supports the second transparent electrode layer 141B on the side opposite the light-controlling layer 140 relative to the second transparent electrode layer 141B.

The driving electrode elements 130 and floating electrode elements 131 described above are included in the first transparent electrode layer 141A. The portion of the first transparent electrode layer 141A located in the driving region 120 is the driving electrode element 130. Of the two surfaces of the first transparent support layer 142A, the surface that contacts the first transparent electrode layer 141A and supports the first transparent electrode layer 141A is the supporting surface 146S, and the surface opposite the supporting surface 146S is the protected surface 146P.

The covering layer 145 is located on the opposite side of the first transparent support layer 142A from the first transparent electrode layer 141A. The covering layer 145 includes an adhesive layer 143 and a protective layer 144. The adhesive layer 143 contacts the protected surface 146P of the first transparent support layer 142A. The protective layer 144 contacts the adhesive layer 143 on the opposite side of the adhesive layer 143 from the first transparent support layer 142A. Note that if the light controlling sheet 110 includes an antiviral film, the light controlling sheet 110 may include an antiviral film instead of the covering layer 145. Alternatively, the light controlling sheet 110 may include an antiviral film on the covering layer 145. In this case, the adhesive layer of the antiviral film contacts the covering layer 145.

The first surface 111F of the light-controlling sheet 110 is the surface of the covering layer 145, specifically, the surface opposite the surface of the protective layer 144 that contacts the adhesive layer 143. The second surface 111R of the light-controlling sheet 110 is the surface of the second transparent support layer 142B that contacts the second transparent electrode layer 141B. The second surface 111R is attached to a transparent plate made of glass, resin, or the like via an adhesive layer. Examples of transparent plates include windowpanes in various buildings such as homes, stations, and airports; partitions installed in offices, medical institutions, and nursing homes; shop windows installed in stores; and windowpanes or windshields in moving objects such as vehicles and aircraft. The surface of the transparent plate may be flat or curved. If the light-controlling sheet 110 includes an antiviral film, the adhesive layer of the antiviral film is located on the second surface 111R of the light-controlling sheet 110, and the antiviral film is attached to the transparent plate.

The first transparent electrode layer 141A supported by the first transparent support layer 142A extends from the driving region 120 to the first connection region 124A, and the first transparent electrode layer 141A is exposed from the light control layer 140 in the first connection region 124A. The first terminal portion 135A is connected to this exposed first transparent electrode layer 141A. In other words, the driving electrode element 130 extends from the driving region 120 to the first connection region 124A, and the first terminal portion 135A is connected to the driving electrode element 130 in the first connection region 124A.

The second transparent electrode layer 141B and the second transparent support layer 142B extend from the driving region 120 to the second connection region 124B, and the second transparent electrode layer 141B is exposed from the light control layer 140 in the second connection region 124B. The second terminal portion 135B is connected to this exposed second transparent electrode layer 141B.

A first wiring section 150A extends from the first terminal section 135A, and a second wiring section 150B extends from the second terminal section 135B. These wiring sections 150A and 150B are connected to a control section 151. The control section 151 applies a voltage signal to the drive electrode element 130 of the first transparent electrode layer 141A via the first wiring section 150A and the first terminal section 135A, and applies a voltage signal to the second transparent electrode layer 141B via the second wiring section 150B and the second terminal section 135B. In this way, the control section 151 controls the potential difference between the first transparent electrode layer 141A and the second transparent electrode layer 141B in the drive region 120. The second transparent electrode layer 141B is controlled to, for example, ground potential. The light control sheet 110 and the control section 151 constitute a light control device.

The light-controlling layer 140 comprises a transparent polymer layer and a liquid crystal composition. The transparent polymer layer has voids, which are filled with a liquid crystal composition. The liquid crystal composition contains liquid crystal molecules. Any of the liquid crystal molecules listed in the first embodiment can be used as the liquid crystal molecules.

The retention type of the liquid crystal composition in the light-controlling layer 140 may be any of the retention types listed in the first embodiment. Note that, like the liquid crystal composition of the first embodiment, the liquid crystal composition may contain, in addition to the liquid crystal molecules described above, monomers for forming a transparent polymer layer, dichroic dyes, and the like.

The first transparent electrode layer 141A and the second transparent electrode layer 141B are each conductive and transparent to light in the visible region. The material of the transparent electrode layers 141A and 141B may be any of the materials listed in the first embodiment.

The first transparent support layer 142A and the second transparent support layer 142B are each a substrate that is transparent to light in the visible range. The material of the transparent support layers 142A and 142B may be any of the materials listed in the first embodiment.

The adhesive layer 143 is a layer that is transparent to light in the visible range and is made of a resin that has adhesive and insulating properties. The adhesive layer 143 is made of an optical clear adhesive (OCA).

Protective layer 144 is a layer that is transparent to light in the visible range. Protective layer 144 is made of a synthetic resin, such as polyethylene terephthalate, polyethylene naphthalate, polymethyl methacrylate, polycarbonate, polyolefin, or triacetyl cellulose. Protective layer 144 may also have an anti-reflection function.

Each of the first terminal portion 135A and the second terminal portion 135B includes, for example, a conductive adhesive layer and a wiring substrate. The conductive adhesive layer may be any of the adhesive layers listed in the first embodiment. The wiring substrate is, for example, a flexible printed circuit (FPC), similar to the wiring substrate of the first embodiment.

Alternatively, each of the first terminal portion 135A and the second terminal portion 135B may have a structure in which a conductive material such as a conductive tape and a conductor are joined by soldering.
In the driving region 120, the light-controlling layer 140 changes the orientation of the liquid crystal molecules in response to a change in voltage generated between the two transparent electrode layers 141A and 141B. The change in orientation of the liquid crystal molecules changes the degree of scattering, absorption, and transmission of visible light that enters the light-controlling layer 140.

Specifically, when no voltage signal is applied to the transparent electrode layers 141A and 141B, the orientation of the long axes of the liquid crystal molecules is irregular. As a result, the degree of scattering of light incident on the dimming layer 140 increases, causing the driving region 120 to appear cloudy. In other words, when no driving voltage is applied to the dimming layer 140, the driving region 120 is opaque. On the other hand, when a voltage signal is applied to the transparent electrode layers 141A and 141B and a potential difference of a predetermined value or greater is generated between the first transparent electrode layer 141A and the second transparent electrode layer 141B, the liquid crystal molecules are oriented, with their long axes oriented along the electric field direction between the transparent electrode layers 141A and 141B. As a result, light is more easily transmitted through the dimming layer 140, and the driving region 120 becomes transparent.

Figure 21 is a cross-sectional view taken along line II-II in Figure 19, showing the cross-sectional structure of the light-controlling sheet 110 in the boundary region 123 and the driving region 120 and floating region 122 sandwiching the boundary region 123.

As shown in FIG. 21, in the first transparent electrode layer 141A, the driving electrode elements 130 are located in the driving region 120, and the floating electrode elements 131 are located in the floating region 122. In other words, the driving electrode elements 130 and the floating electrode elements 131 are separate layered bodies aligned along the support surface 146S.

The driving electrode element 130 and the floating electrode element 131 are separated by a groove 132. The depth direction of the groove 132 is the thickness direction of the first transparent electrode layer 141A, and the groove 132 penetrates the first transparent support layer 142A and the first transparent electrode layer 141A in the depth direction. Separation by the groove 132 means that the driving electrode element 130 and the floating electrode element 131 are insulated from each other.

When viewed from a position facing the first surface 111F of the light-modulating sheet 110, the region where the grooves 132 are located is the boundary region 123. As described above, the boundary region 123 has a closed frame shape that surrounds the floating region 122; that is, the grooves 132 extend in a direction along the support surface 146S and have a closed frame shape that surrounds the entire periphery of the floating electrode elements 131 when viewed from a position facing the first surface 111F. Because no wiring for applying a voltage signal is connected to the floating electrode elements 131, the floating electrode elements 131 are electrically floating.

Therefore, in the floating region 122, the degree of scattering of light incident on the switchable layer 140 is always large. Furthermore, since no electrode elements are located in the first transparent electrode layer 141A in the boundary region 123, the degree of scattering of light incident on the switchable layer 140 is always large even in the boundary region 123. Therefore, the non-driven region 121 always appears cloudy.

The groove 132 has an opening 133 on the protected surface 146P of the first transparent support layer 142A. The opening 133 is covered with an adhesive layer 143 of the covering layer 145. Furthermore, an adhesive portion 147 extending from the adhesive layer 143 extends into the groove 132, filling the groove 132. The adhesive portion 147 is made of the same material as the adhesive layer 143. The adhesive portion 147 is an example of a filling portion.

Filling the grooves 132 with insulating adhesive portions 147 improves the reliability of the insulation between the drive electrode elements 130 and the floating electrode elements 131. Furthermore, the adhesive that makes up the adhesive layer 143 and adhesive portions 147 is a material that easily ensures fluidity and flexibility during manufacturing, allowing the grooves 132 to be filled accurately. Furthermore, because the protective layer 144 is laminated on the adhesive layer 143, dust adhesion to the first surface 111F of the light controlling sheet 110 is reduced compared to when the adhesive layer 143 is exposed, and the light controlling sheet 110 is easier to handle.

Furthermore, by filling the groove 132 with the adhesive portion 147, the groove 132 is less noticeable, i.e., the boundary region 123 is less noticeable, when viewed from a position facing the first surface 111F of the light controlling sheet 110. Furthermore, by covering the opening 133 of the groove 132 with the adhesive layer 143 and protective layer 144, the groove 132 is further less noticeable.

To more effectively reduce the visibility of grooves 132, it is preferable that the refractive indices of first transparent electrode layer 141A, first transparent support layer 142A, adhesive layer 143 and adhesive portion 147, and protective layer 144 are close to each other. The smaller the difference in refractive index between these layers, the less light is reflected or refraction near grooves 132, making grooves 132 less visible.

For example, the refractive index of indium tin oxide, which is widely used for the first transparent electrode layer 141A, is approximately 2.1 to 2.2, while the refractive index of polyethylene terephthalate and acrylic resins, which are widely used for the first transparent support layer 142A, is approximately 1.4 to 1.5. Therefore, the refractive index of the adhesive that makes up the adhesive layer 143 and adhesive portion 147 is preferably 1.4 or more and 1.5 or less, and the refractive index of the protective layer 144 is preferably 1.4 or more and 1.6 or less.

The grooves 132 may extend in the depth direction into the light-switching layer 140. For example, as shown in FIG. 22, the grooves 132 may penetrate the light-switching layer 140, or the bottoms of the grooves 132 may be located inside the light-switching layer 140. Also, for example, as shown in FIG. 23, the grooves 132 may penetrate the light-switching layer 140 and the second transparent electrode layer 141B.

If the grooves 132 extend to the inside of the light-controlling layer 140, the reliability of insulation between the driving electrode elements 130 and the floating electrode elements 131 can be increased.
Furthermore, in a configuration in which the groove 132 penetrates the second transparent electrode layer 141B, the portion of the second transparent electrode layer 141B located in the floating region 122 is insulated from the surroundings, and no voltage signal is applied to this portion. Therefore, regardless of the potential of the second transparent electrode layer 141B in the drive region 120, the formation of a potential difference between the first transparent electrode layer 141A and the second transparent electrode layer 141B in the floating region 122 is suppressed. In other words, regardless of the magnitude of the voltage signal applied to the second transparent electrode layer 141B in the drive region 120 or the state of its fluctuation, the orientation state of the liquid crystal molecules in the dimming layer 140 in the floating region 122 does not change. Therefore, the degree of freedom in controlling the potential of the second transparent electrode layer 141B in the drive region 120 is increased.

The width of groove 132 in the depth direction may or may not be constant. For example, the width of groove 132 may decrease toward the bottom of the groove. In other words, groove 132 may have a V-shaped cross section. If groove 132 has a V-shaped cross section, it is easy to fill groove 132 by flowing adhesive into groove 132.

To prevent the grooves 132 from being noticeable when viewed from a position facing the first surface 111F of the light-adjusting sheet 110, the width of the grooves 132 at the openings 133 is preferably 1 mm or less, and more preferably 0.5 mm or less.

[Method of manufacturing light controlling sheet]
A method for manufacturing the light controlling sheet 110 will be described with reference to FIGS.
24 , first, a light control layer 140 is formed between a first transparent electrode layer 141A supported by a first transparent support layer 142A and a second transparent electrode layer 141B supported by a second transparent support layer 142B, thereby forming a stacked body 160 consisting of the light control layer 140, transparent electrode layers 141A and 141B, and transparent support layers 142A and 142B. At this point, the first transparent electrode layer 141A is a uniform layer that is not divided into the driving electrode elements 130 and the floating electrode elements 131.

Next, as shown in Figure 25, grooves 132 are formed in the laminate 160 from the outside of the laminate 160. In detail, grooves 132 are formed by cutting into the laminate 160 from the side where the first transparent support layer 142A is located relative to the light-controlling layer 140. A cutting device such as a cutting plotter or laser cutter is used to form the grooves 132.

Next, as shown in Figure 26, adhesive is applied to the first transparent support layer 142A of the laminate 160, thereby forming the adhesive layer 143 and adhesive portion 147. The groove 132 is filled with the adhesive portion 147. Then, as shown in Figure 27, the protective layer 144 is attached to the adhesive layer 143.

The adhesive layer 143 and adhesive portion 147 may be formed by applying a film-like adhesive, such as an OCA film, to the laminate 160, or by applying a flowable adhesive to the laminate 160. Even if the adhesive is in film form, the film made of this adhesive is flexible, so it is possible to fill the grooves 132 with the adhesive. Furthermore, heat and pressure may be applied when forming the adhesive layer 143 and adhesive portion 147, or when laminating the protective layer 144.

In addition, instead of disposing an adhesive on the laminate 160, an adhesive may be disposed on the surface of the protective layer 144 to form an adhesive layer 143, and the protective layer 144 and adhesive layer 143 may then be bonded to the laminate 160.

The connection region 124 is formed by cutting out a portion of the constituent layers from the laminate 160. The connection region 124 may be formed in the same process as the formation of the groove 132, or may be formed after the adhesive layer 143 and protective layer 144 are laminated onto the laminate 160. If the connection region 124 is formed in the same process as the formation of the groove 132, the number of processes and time required to manufacture the light controlling sheet 110 can be reduced.

Incidentally, because the first transparent electrode layer 141A is very thin compared to the dimming layer 140, forming the groove 132 so that its bottom is located within the dimming layer 140 reduces the burden required to control the depth of the groove 132, compared to forming the groove 132 so that it penetrates the first transparent electrode layer 141A but does not extend into the dimming layer 140. Therefore, if the bottom of the groove 132 is located within the dimming layer 140, it is possible to increase the reliability of insulation between the drive electrode element 130 and the floating electrode element 131 while minimizing the increase in the burden required for manufacturing.

As described above, in this embodiment, the grooves 132 for insulating the driving electrode elements 130 and the floating electrode elements 131 are formed by cutting the transparent electrode layers 141A, 141B, the transparent support layers 142A, 142B, and the light-controlling layer 140 from the outside into the laminate 160 made up of these layers after these layers have been laminated. Therefore, compared to dividing the electrode elements using etching or the like before forming the laminate 160, it is possible to reduce the number of steps and time required to separate the driving electrode elements 130 and the floating electrode elements 131 and simplify the equipment. In addition, there is a greater degree of freedom in the shapes of the driving electrode elements 130 and the floating electrode elements 131, and it is also possible to easily accommodate design changes to the shapes of the driving electrode elements 130 and the floating electrode elements 131.

[Effect]
FIG. 28 schematically shows the degree of transparency of the light controlling sheet 110 when the light controlling sheet 110 is not driven, that is, when no voltage signal is applied to the transparent electrode layers 141A and 141B.

As shown in Figure 28, when the light-adjusting sheet 110 is not driven, both the driving area 120 and the floating area 122 are opaque. Therefore, the entire surface of the light-adjusting sheet 110 appears whitish or cloudy, for example, and images such as letters and pictures formed in the floating area 122 cannot be seen.

In contrast, when the light-adjusting sheet 110 is driven, that is, when a voltage signal is applied to the transparent electrode layers 141A and 141B, the drive region 120 becomes transparent, while the floating region 122 remains opaque. Therefore, as shown in Figure 19 above, only the floating region 122 appears whitish or cloudy, for example, and images such as letters and pictures made up of the floating region 122 become visible.

As such, with the light-adjusting sheet 110 of this embodiment, regions with different light transmittances are formed within the surface of the light-adjusting sheet 110, and the difference in light transmittance between these regions only appears when the light-adjusting sheet 110 is driven. Therefore, when the light-adjusting sheet 110 is driven, images such as letters and pictures formed by the floating area 122 are visible, making it possible to decorate the space in which the light-adjusting sheet 110 is placed. Furthermore, by switching between driving and de-driving the light-adjusting sheet 110, the appearance of the images can be switched on or off, allowing the decorative state of the space to be dynamically changed. This makes it possible to improve the design of the light-adjusting sheet 110.

When the dimming layer 140 is present in the boundary region 123, the boundary region 123 is always opaque. Therefore, when the dimming sheet 110 is not driven, both the driving region 120 and the non-driving region 121 appear opaque, and when the dimming sheet 110 is driven, the non-driving region 121 appears opaque. On the other hand, when the grooves 132 separating the driving electrode elements 130 and the floating electrode elements 131 penetrate the dimming layer 140 and no dimming layer 140 is present in the boundary region 123, the boundary region 123 is always transparent. Therefore, when the dimming sheet 110 is not driven, the driving region 120 and the floating region 122 are opaque, while the boundary region 123 is transparent. However, because the boundary region 123 is thin and linear, it is not very noticeable, and images such as letters and pictures made up of the floating region 122 are not easily visible. When the dimming sheet 110 is driven, the boundary region 123 appears transparent together with the driving region 120.

To prevent the boundary region 123 from being noticeable when the light-adjusting sheet 110 is not driven, it is preferable that the grooves 132 do not penetrate the light-adjusting layer 140, and that at least a portion of the light-adjusting layer 140 is present in the boundary region 123 in the thickness direction. Alternatively, as part of the design of the light-adjusting sheet 110, the boundary region 123 may be made more noticeable so that the border-shaped boundary region 123 is visible when the light-adjusting sheet 110 is not driven. In this case, the light-adjusting layer 140 does not need to be present in the boundary region 123, and the width of the boundary region 123 may be increased.

As described above, according to the third embodiment of the light controlling sheet, the following effects can be obtained.
(3-1) By controlling the application of voltage signals to the driving electrode elements 130 and the floating electrode elements 131, it is possible to change the difference in light transmittance between the driving region 120 and the floating region 122, thereby changing the visibility of the image formed by the floating region 122. Therefore, it is possible to dynamically change the decorative state of the space created by the light controlling sheet 110, and it is possible to improve the design of the light controlling sheet 110.

(3-2) Grooves 132 for insulating the driving electrode elements 130 and the floating electrode elements 131 extend through the first transparent support layer 142A and the first transparent electrode layer 141A. This structure can be formed by laminating the transparent electrode layers 141A, 141B and the transparent support layers 142A, 142B with the light-controlling layer 140, and then cutting a notch from the surface of the first transparent support layer 142A into the first transparent support layer 142A and the first transparent electrode layer 141A. This makes it easy to separate the driving electrode elements 130 and the floating electrode elements 131. This also increases the degree of freedom in the shapes of the driving electrode elements 130 and the floating electrode elements 131, and further enables easy adaptation to design changes in the shapes of the driving electrode elements 130 and the floating electrode elements 131.

(3-3) Because the openings 133 of the grooves 132 are covered with the covering layer 145, it is possible to prevent conductive materials from entering the grooves 132 and causing electrical conduction between the drive electrode elements 130 and the floating electrode elements 131. Furthermore, it is possible to prevent the grooves 132 from being conspicuous when viewed from the first surface 111F of the light control sheet 110.

(3-4) Because the grooves 132 are filled with filling sections that extend continuously from the covering layer 145, the reliability of the insulation between the drive electrode elements 130 and the floating electrode elements 131 is improved. Furthermore, the covering layer 145 includes an adhesive layer 143 and a protective layer 144, and the filling sections are adhesive sections 147 that extend from the adhesive layer 143. In other words, because the grooves 132 are filled with a flexible and fluid adhesive, filling the grooves 132 is easy. Furthermore, because the protective layer 144 is laminated on the adhesive layer 143, adhesion of dust and other particles to the adhesive layer 143 is suppressed, and the light control sheet 110 is easier to handle.

(3-5) If the refractive index of the layer included in the covering layer 145 is 1.4 or more and 1.6 or less, the refractive index of the covering layer 145 is greater than that of air, which tends to reduce the difference in refractive index between the first transparent support layer 142A and the covering layer 145. Therefore, compared to when the grooves 132 are exposed to air, the difference in refractive index at the interface near the grooves 132 is smaller, which reduces light reflection and refraction, making the grooves 132 less noticeable.

(3-6) If the grooves 132 extend into the dimming layer 140 in the depth direction, the reliability of insulation between the drive electrode elements 130 and the floating electrode elements 131 is improved.

(3-7) In a configuration in which the grooves 132 penetrate the dimming layer 140 and the second transparent electrode layer 141B in the depth direction of the grooves 132, the second transparent electrode layer 141B is also divided into multiple parts that are insulated from each other, corresponding to the drive electrode elements 130 and the floating electrode elements 131. Therefore, the potential difference between the first transparent electrode layer 141A and the second transparent electrode layer 141B can be accurately controlled for each divided region. This makes it possible to accurately control the light transmittance of the regions where the electrode elements 130, 131 are located.

(3-8) When viewed from a position facing the first surface 111F, the grooves 132 have a closed frame shape that surrounds the floating electrode elements 131. This makes it easy to insulate the drive electrode elements 130 from the floating electrode elements 131 so that the floating regions 122 form letters, numbers, symbols, figures, pictures, etc., and also increases the degree of freedom in the arrangement and shape of the floating electrode elements 131. This therefore increases the degree of freedom in the composition of the image that appears on the light control sheet 110.

(3-9) Of the driving electrode element 130 and the floating electrode element 131, only the driving electrode element 130 is connected to the terminal portions 135A and 135B. This makes it possible to switch between a state in which there is no difference in light transmittance between the driving region 120 and the floating region 122 and a state in which there is a difference in light transmittance between the driving region 120 and the floating region 122, depending on whether or not a voltage signal is applied to the driving electrode element 130. Therefore, the design of the light control sheet can be improved with a simple configuration.

[Modification of the third embodiment]
The third embodiment described above can be modified as follows: The following modifications may also be combined with each other.

As shown in FIG. 29, the light-controlling sheet 110 may include a first alignment layer 148A and a second alignment layer 148B. The first alignment layer 148A is located between the light-controlling layer 140 and the first transparent electrode layer 141A and is in contact with these layers. The second alignment layer 148B is located between the light-controlling layer 140 and the second transparent electrode layer 141B and is in contact with these layers.

Each of the first alignment layer 148A and the second alignment layer 148B is, for example, a vertical alignment film. The vertical alignment film aligns the long axis direction of the liquid crystal molecules along the thickness direction of the light control layer 140. The material of each of the first alignment layer 148A and the second alignment layer 148B may be any of the materials listed in the first embodiment.

When the light-controlling sheet 110 includes alignment layers 148A and 148B, in the driving region 120, when no voltage signal is applied to the transparent electrode layers 141A and 141B, the long axis direction of the liquid crystal molecules is oriented along the thickness direction of the light-controlling layer 140. Therefore, the driving region 120 is transparent. On the other hand, when a voltage signal is applied to the transparent electrode layers 141A and 141B in the driving region 120, the long axis direction of the liquid crystal molecules is oriented to intersect the thickness direction of the light-controlling layer 140. Therefore, the driving region 120 appears cloudy and opaque.

When the light-controlling sheet 110 includes alignment layers 148A and 148B, the long axis direction of the liquid crystal molecules in the floating region 122 is always oriented along the thickness direction of the light-controlling layer 140, so the floating region 122 is always transparent.

Therefore, when the light-adjusting sheet 110 is not driven, both the driving area 120 and the floating area 122 are transparent, and images such as letters and patterns made up of the floating area 122 are not visible. On the other hand, when the light-adjusting sheet 110 is driven, the driving area 120 becomes opaque, while the floating area 122 is transparent, so images such as letters and patterns made up of the floating area 122 become visible.

As in the above embodiment, the grooves 132 for separating the driving electrode elements 130 and the floating electrode elements 131 need only penetrate at least the first transparent support layer 142A and the first transparent electrode layer 141A. The grooves 132 may also penetrate part or all of the first alignment layer 148A, the light control layer 140, the second alignment layer 148B, and the second transparent electrode layer 141B.

If the grooves 132 do not penetrate the first alignment layer 148A, or if the grooves 132 penetrate the light-controlling layer 140, the boundary region 123 is always transparent and appears to be integrated with the floating region 122. Therefore, to prevent the boundary region 123 from being noticeable when the light-controlling sheet 110 is not driven, it is preferable that the grooves 132 do not penetrate the first alignment layer 148A, or extend to a position where they penetrate the light-controlling layer 140.

As described above, even when the light-adjusting sheet 110 includes alignment layers 148A and 148B, the surface of the light-adjusting sheet 110 contains the driving region 120 and the floating region 122, which are regions where a difference in light transmittance appears only when the light-adjusting sheet 110 is driven. This makes it possible to improve the design of the light-adjusting sheet 110.

The protective layer 144 may be a layer with a lower light transmittance than the first transparent support layer 142A. For example, the protective layer 144 may be a half-mirror film or a colored film such as a smoked film. If the light transmittance of the protective layer 144 is lower than that of the first transparent support layer 142A, the appearance of the light-adjusting sheet 110 changes depending on the intensity of the light source behind the light-adjusting sheet 110. For example, if the protective layer 144 is a half-mirror film, when the light source behind the light-adjusting sheet 110 is weak, the first surface 111F of the light-adjusting sheet 110 will appear as a mirror. Also, if the protective layer 144 is a smoked film, when the light source behind the light-adjusting sheet 110 is weak, the light-adjusting sheet 110 will appear as a dark color such as black. Therefore, the decorative state of the space created by the light-adjusting sheet 110 can be changed in a more diverse manner, further improving the design of the light-adjusting sheet 110.

- The number of layers and materials included in the covering layer 145 are not particularly limited. The covering layer 145 may include only one of the adhesive layer 143 and the protective layer 144, or may include a layer different from the adhesive layer 143 and the protective layer 144. As long as the covering layer 145 covers the opening 133 of the groove 132, it can achieve the effect of preventing conductive materials from entering the groove 132.

The filling portion that fills the groove 132 may also be made of a material other than an adhesive. For example, a thermosetting resin or photocurable resin used as a hard coating material may be applied to the first transparent support layer 142A in which the groove 132 is formed, and the applied resin may be cured by heat or light to form the filling portion and covering layer 145. In this case, the filling portion and covering layer 145 are made of a curable resin, and the filling portion extends continuously from the covering layer 145 into the groove 132.

Even if the materials of the filling portion and the covering layer 145 are different from those in the above embodiment, in order to prevent the groove 132 from being noticeable, it is preferable that the refractive index of the layers contained in the filling portion and the covering layer 145 be 1.4 or more and 1.6 or less.
As long as the opening 133 of the groove 132 is covered with the covering layer 145, the groove 132 does not need to be partially or entirely filled with the filling portion.

- The cover layer 145 may include a layer that is UV-absorbing. For example, at least one of the adhesive layer 143 and the protective layer 144 may be UV-absorbing. With this configuration, UV rays contained in sunlight or other light irradiated onto the light-control sheet 110 are absorbed by the cover layer 145 and are less likely to reach the light-control layer 140. This prevents deterioration of the liquid crystal composition's functionality.

- The grooves 132 located in the boundary region 123 do not have to have a closed frame shape surrounding the floating electrode elements 131, as long as they extend in a direction along the support surface 146S of the first transparent support layer 142A. For example, as shown in Figure 30, when viewed from a position facing the first surface 111F, the boundary region 123 and grooves 132 may extend from a starting point located at the end 110E of the light-adjusting sheet 110, through the periphery of the floating region 122 and floating electrode elements 131, to an ending point located at the end 110E of the light-adjusting sheet 110. In this case, the ends of the floating region 122 and floating electrode elements 131 are located at the end 110E of the light-adjusting sheet 110. In Figure 30, the lower side of the rectangular light adjusting sheet 110 is shown as the end 110E, but the end 110E where the boundary region 123 and the groove 132 start and end points are located may be any of the upper side, left side, or right side, or may be multiple of these sides.

In the above embodiment, a voltage signal is applied to the driving electrode element 130, which is the first electrode element, and no voltage signal is applied to the floating electrode element 131, which is the second electrode element. Alternatively, voltage signals may be applied separately to the first electrode element and the second electrode element. Wiring for applying a voltage signal to the second electrode element is connected to the end of the second electrode element via a terminal portion. The terminal portion connected to the first electrode element and the terminal portion connected to the second electrode element are separate terminal portions for each voltage signal. As described above, if the second electrode element is located at the end of the light control sheet 110, it is easy to connect wiring to the second electrode element.

For example, the first region where the first electrode elements are located can be switched between transparent and opaque by switching the state of a voltage signal applied to the first electrode elements. The second region where the second electrode elements are located can be switched between transparent and opaque, independently of the first region, by switching the state of a voltage signal applied to the second electrode elements. This configuration makes it possible to switch between four states: a state in which both the first and second regions are opaque; a state in which the first region is opaque and the second region is transparent; a state in which the first region is transparent and the second region is opaque; and a state in which both the first and second regions are opaque. This allows for a more diverse range of changes to the decorative state of a space using the light-controlling sheet 110, further improving the design of the light-controlling sheet 110.

Furthermore, for example, the light transmittance of at least one of the first and second regions may be controlled to a light transmittance that corresponds between transparency and opacity. In a light-controlling sheet 110 having a light-controlling layer 140 containing a liquid crystal composition, when the potential difference between the transparent electrode layers 141A and 141B is within a predetermined range, the light transmittance of the light-controlling sheet 110 gradually changes as the potential difference changes. Therefore, by controlling the potential difference between the transparent electrode layers 141A and 141B in the first or second region to a value between the potential difference that makes the region transparent and the potential difference that makes the region opaque, the region can be controlled to be translucent, with a light transmittance that corresponds between transparency and opaque.

Specifically, for example, the first region can be switched between transparent and opaque by switching the state of application of a voltage signal to the first electrode element, and the second region can be switched between translucent and opaque by switching the state of application of a voltage signal to the second electrode element. When the first region is transparent, the second region is controlled to be translucent. This configuration makes it possible to switch between a state in which both the first region and the second region are opaque and a state in which the first region is opaque and the second region is translucent. This also makes it possible to improve the design of the light-controlling sheet 110.
In the above embodiment, the driving region 120 is the first region, and the floating region 122 is the second region.

[Fourth embodiment]
A fourth embodiment of the light-adjusting sheet will be described with reference to Figures 31 to 37. The light-adjusting sheet of this embodiment is a normal type. A normal type light-adjusting sheet scatters incident light in the region to be driven when no voltage signal is applied to the light-adjusting sheet, reducing the light transmittance, and increases the light transmittance when a voltage signal is applied to the light-adjusting sheet.

[Light control sheet]
31 , the light controlling sheet 210 has a first surface 211F and a second surface 211R that is the surface opposite to the first surface 211F. The light controlling sheet 210 has a driving region 220 and a non-driving region 221.

The driving region 220 is an area where the driving electrode element 230, which is an electrode element to which a voltage signal is applied when the light control sheet 210 is driven, is located. The light transmittance of the driving region 220 changes depending on the state of application of the voltage signal to the driving electrode element 230. The driving electrode element 230 is an example of a first electrode element.

The non-driving region 221 includes a floating region 222 and a boundary region 223 surrounding the floating region 222. The floating region 222 is an area where floating electrode elements 231, which are electrode elements to which no voltage signal is applied when the light controlling sheet 210 is driven, are located. The floating electrode elements 231 are an example of second electrode elements. The boundary region 223 is located between the driving region 220 and the floating region 222, and has a closed frame shape that surrounds the floating region 222. No electrode elements are located in the boundary region 223. Note that the width of the boundary region 223 is exaggerated in the drawings for ease of understanding. The light transmittance of the non-driving region 221 does not change whether the light controlling sheet 210 is driven or not.

The non-driven area 221 displays a pattern on the light-adjusting sheet 210. The pattern may be, for example, one or a combination of letters, numbers, symbols, figures, pictures, designs, etc. Note that while the light-adjusting sheet 210 shown in Figure 31 has one star-shaped figure as the non-driven area 221, it may also have multiple non-driven areas 221 that are separated from each other. In other words, the light-adjusting sheet 210 may have multiple boundary areas 223 that form a closed area.

The connection region 224 is an area for applying a voltage signal to the driving region 220, and is connected to external wiring 225. The connection region 224 and the driving region 220 are adjacent to each other. There are no particular restrictions on the location of the connection region 224. The connection region 224 is located, for example, in a corner of the light-controlling sheet 210.

Figure 32 is a cross-sectional view taken along line III-III in Figure 31, showing the cross-sectional structure of the light-controlling sheet 210 in the drive region 220 and connection region 224. Note that the thickness ratios of the layers in Figure 32 are shown for the sake of convenience and are not limited to those shown in Figure 32. Also, for the sake of convenience, the antiviral film provided on the light-controlling sheet 210 is omitted from Figure 32. The light-controlling sheet 210 of the fourth embodiment can be provided with the antiviral film provided on the light-controlling sheet of the first embodiment, as well as the antiviral film or antiviral layer described in the modified example of the first embodiment.

As shown in Figure 32, the light-controlling sheet 210 has a light-controlling layer 211, a first transparent electrode layer 212A, a second transparent electrode layer 212B, a first transparent support layer 213A, and a second transparent support layer 213B. The light-controlling layer 211 is sandwiched between the first transparent electrode layer 212A and the second transparent electrode layer 212B. The first transparent support layer 213A supports the first transparent electrode layer 212A on a support surface 2130 opposite the light-controlling layer 211 relative to the first transparent electrode layer 212A, and the second transparent support layer 213B supports the second transparent electrode layer 212B on the opposite side of the second transparent electrode layer 212B from the light-controlling layer 211. The light-controlling layer 211 may have a single-layer structure or a multi-layer structure. The multilayered light control layer 211 may include a functional layer with a light control function and a thin layer that improves adhesion between the functional layer and the first transparent electrode layer 212A and between the functional layer and the second transparent electrode layer 212B.

The light-controlling sheet 210 further includes a protective layer 244. The protective layer 244 is located on the opposite side of the first transparent support layer 213A from the first transparent electrode layer 212A. The protective layer 244 is fixed to the first transparent support layer 213A via an adhesive layer (not shown). If the light-controlling sheet 210 includes an antiviral film, the light-controlling sheet 210 may include the antiviral film instead of the protective layer 244 and adhesive layer. Alternatively, the light-controlling sheet 210 may include an antiviral film on the protective layer 244. In this case, the adhesive layer of the antiviral film contacts the protective layer 244.

The first surface 211F of the light-controlling sheet 210 is the surface of the protective layer 244 opposite the surface facing the first transparent support layer 213A. The second surface 211R of the light-controlling sheet 210 is the surface of the second transparent support layer 213B opposite the surface facing the second transparent electrode layer 212B. The second surface 211R is attached to a transparent plate made of glass, resin, or the like via an adhesive layer (not shown). Examples of transparent plates include windowpanes in various buildings such as homes, stores, stations, and airports; partitions installed in offices, medical institutions, and nursing homes; shop windows installed in stores; and windowpanes or windshields in moving objects such as vehicles and aircraft. The surface of the transparent plate may be flat or curved. If the light-controlling sheet 210 includes an antiviral film, the adhesive layer of the antiviral film is located on the second surface 211R of the light-controlling sheet 210, and the antiviral film is attached to the transparent plate.

The connection region 224 includes a first connection region 224A to which external wiring 225 is connected for applying a voltage signal to the first transparent electrode layer 212A, and a second connection region 224B to which external wiring 225 is connected for applying a voltage signal to the second transparent electrode layer 212B.

The first connection region 224A is an area where the light control layer 211, second transparent electrode layer 212B, and second transparent support layer 213B are not located, leaving a portion of the first transparent electrode layer 212A exposed. The first terminal 250A is connected to the portion of the first transparent electrode layer 212A exposed in the first connection region 224A. In other words, the drive electrode element 230 extends from the drive region 220 to the first connection region 224A, and the first terminal 250A is connected to the drive electrode element 230 in the first connection region 224A.

The second connection region 224B is an area where the light control layer 211, first transparent electrode layer 212A, first transparent support layer 213A, and protective layer 244 are not located, leaving a portion of the second transparent electrode layer 212B exposed. The second terminal 250B is connected to the portion of the second transparent electrode layer 212B exposed in the second connection region 224B. In other words, the drive electrode element 230 extends from the drive region 220 to the second connection region 224B, and the second terminal 250B is connected to the drive electrode element 230 in the second connection region 224B.

External wiring 225 extends from each of the first terminal 250A and the second terminal 250B, and these external wiring 225 are connected to the control unit 250. The control unit 250 applies a voltage signal to the drive electrode element 230 of the first transparent electrode layer 212A through the first terminal 250A, and applies a voltage signal to the second transparent electrode layer 212B through the second terminal 250B. In this way, the control unit 250 controls the potential difference between the first transparent electrode layer 212A and the second transparent electrode layer 212B in the drive region 220. The second transparent electrode layer 212B is controlled to, for example, ground potential. The light control sheet 210 and the control unit 250 constitute a light control device.

The light-controlling layer 211 comprises a transparent polymer layer and a liquid crystal composition. The transparent polymer layer has voids into which the liquid crystal composition is filled. The liquid crystal composition fills the voids in the transparent polymer layer. The liquid crystal composition contains liquid crystal molecules. The liquid crystal molecules may be any of the liquid crystal molecules listed in the first embodiment. When the light-controlling layer 211 has a single-layer structure, the light-controlling layer 211 consists only of a functional layer comprising a transparent polymer layer and a liquid crystal composition.

The retention type of the liquid crystal composition may be any of the retention types listed in the first embodiment. Note that, like the liquid crystal composition of the first embodiment, the liquid crystal composition may contain, in addition to the liquid crystal molecules described above, a monomer for forming a transparent polymer layer, a dichroic dye, and the like.

The first transparent electrode layer 212A and the second transparent electrode layer 212B are each electrically conductive and transparent to light in the visible region. The materials used to form the first transparent electrode layer 212A and the second transparent electrode layer 212B may be any of the materials listed in the first embodiment.

Each of the first transparent support layer 213A and the second transparent support layer 213B is a substrate that is transparent to light in the visible region. The materials used to form the first transparent support layer 213A and the second transparent support layer 213B may be any of the materials listed in the first embodiment.

Each of the first terminal portion 250A and the second terminal portion 250B includes, for example, a conductive adhesive layer and a wiring substrate. The conductive adhesive layer may be any of the adhesive layers listed in the first embodiment. As in the first embodiment, the wiring substrate is, for example, a flexible printed circuit (FPC).

Alternatively, each of the first terminal portion 250A and the second terminal portion 250B may have a structure in which a conductive material such as conductive tape is joined to the external wiring 225 by soldering or the like, as in the first embodiment.

In the driving region 220, the dimming layer 211 changes the orientation of the liquid crystal molecules in response to changes in the voltage generated between the two transparent electrode layers 212A and 212B. The change in orientation of the liquid crystal molecules alters the degree of scattering, absorption, and transmission of visible light entering the dimming layer 211. Specifically, when no voltage signal is applied to the first transparent electrode layer 212A and the second transparent electrode layer 212B of the driving region 220, the orientation of the long axis direction of the liquid crystal molecules is irregular. As a result, the degree of scattering of light incident on the dimming layer 211 increases, and the driving region 220 appears cloudy. In other words, when no voltage signal is applied to the dimming layer 211, the driving region 220 is opaque. On the other hand, when a voltage signal is applied to the transparent electrode layers 212A and 212B, and a potential difference of a predetermined value or greater occurs between the first transparent electrode layer 212A and the second transparent electrode layer 212B, the liquid crystal molecules are oriented, with their long axis directions aligned with the electric field direction between the transparent electrode layers 212A and 212B. As a result, light can more easily pass through the dimming layer 211, and the driving region 220 becomes transparent.

Figure 33 is a cross-sectional view taken along line IV-IV in Figure 31, showing the cross-sectional structure of the light-controlling sheet 210 in the boundary region 223 and the driving region 220 and floating region 222 sandwiching the boundary region 223.

As shown in Figure 33, the light-controlling layer 211 includes a plurality of spacers 215. The spacers 215 maintain a substantially constant distance between the first transparent electrode layer 212A and the second transparent electrode layer 212B. Furthermore, in the first transparent electrode layer 212A, driving electrode elements 230 are located in the driving region 220, and floating electrode elements 231 are located in the floating region 222. In other words, the driving electrode elements 230 and the floating electrode elements 231 are separate layered bodies aligned along the support surface 2130 of the first transparent support layer 213A.

The driving electrode element 230 and the floating electrode element 231 are separated by a groove 2120. The depth direction of the groove 2120 is the thickness direction of the first transparent electrode layer 212A. In this embodiment, the groove 2120 has an opening 2122 on the side of the first transparent electrode layer 212A facing the light control layer 211, penetrates the first transparent electrode layer 212A, and extends partway through the thickness direction of the first transparent support layer 213A. Separation by the groove 2120 means that the driving electrode element 230 and the floating electrode element 231 are insulated from each other. The region where this groove 2120 is located is the boundary region 223.

Figure 34 is an enlarged view of the cross-sectional structure of the groove 2120 and its surrounding area in Figure 33. The sum of the thickness T1 of the first transparent support layer 213A and the thickness T2 of the first transparent electrode layer 212A, that is, the thickness T3, is 20 μm or more and 200 μm or less. The thickness T2 of the first transparent electrode layer 212A is several tens of nanometers. The thickness of the light-controlling layer 211 is 0.5 μm or more and 460 μm or less. The overall thickness of the light-controlling sheet 210 is 45 μm or more and 500 μm or less. The thickness of the second transparent support layer 213B may be the same as or different from the thickness of the first transparent support layer 213A. Similarly, the thickness of the second transparent electrode layer 212B may be the same as or different from the thickness of the first transparent electrode layer 212A.

When the depth of groove 2120 is "D1," the depth of groove 2120 satisfies "T2 < D1 < T3." As described above, groove 2120 has a depth that penetrates through first transparent electrode layer 212A but does not penetrate through first transparent support layer 213A.

The width W1 of the groove 2120 is smaller than the diameter φ1 of the spacer 215 (width W1 < diameter φ1). Note that if there is variation in the particle size of the spacer 215, the diameter φ1 of the spacer 215 is the diameter φ1 of the spacer 215 with the smallest particle size. Because the diameter φ1 of the spacer 215 is larger than the width W1 of the groove 2120, it is difficult for the spacer 215 to fit into the groove 2120.

Figure 35 is an SEM photograph of a cross-sectional structure including a groove 2120. The groove 2120 shown in the center of the SEM photograph is open on the side of the light-controlling layer 211, and is therefore filled with a light-controlling material 2110 consisting of a transparent polymer layer of the light-controlling layer 211 and a liquid crystal composition. If the groove 2120 is not filled with the light-controlling material 2110, light that passes through the first transparent support layer 213A and enters the inside of the groove 2120 is reflected by the side of the groove 2120. In this case, the groove 2120 is noticeable when viewed from the outside of the light-controlling sheet 210. However, because the refractive index of the material constituting the first transparent support layer 213A is closer to the refractive index of the light-controlling material 2110 than to the refractive index of air, when the groove 2120 is filled with the light-controlling material 2110 as in this embodiment, the reflectivity on the side of the groove 2120 is reduced, and the groove 2120 becomes less visible when viewed from the outside of the light-controlling sheet 210. Furthermore, even if a small gap 2121 (see Figure 34) remains in the groove 2120, the groove 2120 will not be noticeable if most of the volume of the groove 2120 is filled with the light-adjusting material 2110. In order to achieve the effect of making the groove 2120 less visible from the outside, it is preferable that the filling rate of the light-adjusting material 2110 with respect to the volume of the groove 2120 be 80% or more.

Furthermore, as described above, the width W1 of the groove 2120 is smaller than the diameter φ1 of the spacer 215, which prevents the spacer 215 from entering the groove 2120, thereby preventing the filling of the groove 2120 with the light-adjusting material 2110. Furthermore, since the thickness of the light-adjusting layer 211 is 0.5 μm or greater, the light-adjusting material 2110 is likely to be filled at a filling rate of 80% or greater. The reason for this is not yet clear, but it is thought that by increasing the thickness of the light-adjusting layer 211, a sufficient amount of light-adjusting material 2110 is secured around the opening 2122, making it easier for the light-adjusting material 2110 to fill the groove 2120 when the light-adjusting layer 211 is sandwiched between the first transparent electrode layer 212A and the second transparent electrode layer 212B and a predetermined pressure is applied.

Furthermore, the first transparent electrode layer 212A has a burr 2123 formed around the opening 2122 of the groove 2120. The burr 2123 is generated when forming the groove 2120 in the first transparent electrode layer 212A and protrudes from the periphery of the opening 2122 toward the photochromic layer 211. When forming the groove 2120, the height H1 of the burr 2123 is adjusted to be lower than the thickness T4 of the photochromic layer 211 (H1 < T4). If the height H1 of the burr 2123 exceeds the thickness T4 of the photochromic layer 211, the first transparent electrode layer 212A will come into contact with the second transparent electrode layer 212B via the photochromic layer 211, causing a short circuit between the first transparent electrode layer 212A and the second transparent electrode layer 212B. The height H1 of the burr 2123 may also be set to 0.8 times or less the thickness T4 of the photochromic layer 211. In this way, even if the distance between the first transparent electrode layer 212A and the second transparent electrode layer 212B decreases when the light controlling sheet 210 is attached to a curved surface or when the light controlling sheet 210 is unintentionally pressed, it is possible to sufficiently prevent short circuits between the first transparent electrode layer 212A and the second transparent electrode layer 212B. Note that the depth D1 of the groove 2120 is the length extending in the thickness direction of the first transparent electrode layer 212A from the surface of the first transparent electrode layer 212A facing the light controlling layer 211, and does not include the height of the burrs 2123.

[Method of manufacturing light controlling sheet]
Next, a method for manufacturing the light controlling sheet 210 will be described with reference to FIG.
First, a film 251A including a first transparent electrode layer 212A and a first transparent support layer 213A, and a film 251B including a second transparent electrode layer 212B and a second transparent support layer 213B are prepared. Of these, a groove 2120 is formed in the film 251A including the first transparent electrode layer 212A and the first transparent support layer 213A from the first transparent electrode layer 212A side using a cutting plotter. A control device connected to the cutting plotter operates the cutting plotter according to a design input in advance to form the groove 2120.

The grooves 2120 may be formed using a device other than a cutting plotter. For example, the grooves 2120 may be formed in the first transparent electrode layer 212A using a blade other than a cutting plotter or a laser cutting device. As the laser cutting device, for example, a laser cutter equipped with a _CO2 laser or the like may be used.

Next, a liquid containing spacers 215, whose main material is divinylbenzene or the like, and a dispersion medium for dispersing the spacers 215, is applied to the surfaces of the films 251A, 251B facing the first transparent electrode layer 212A and the second transparent electrode layer 212B. The films with the spacers 215 dispersed therein are then heated to remove the dispersion medium. At this time, the spacers 215 may be dispersed on only one of the films.

A light-adjusting material containing a transparent polymer material and a liquid crystal composition is then applied to the first transparent electrode layer 212A of film 251A, in which grooves 2120 are formed, and to the second transparent electrode layer 212B of film 251B, in which grooves 2120 are not formed. At this time, as shown in Figure 36, the grooves 2120 do not need to be filled with the light-adjusting material. Furthermore, the films 251A and 251B are irradiated with ultraviolet light in a nitrogen atmosphere to form light-adjusting layers 211A and 211B. The pair of films thus obtained are then stacked and bonded together while applying a predetermined amount of pressure. This causes the light-adjusting material to fill the grooves 2120.

The light-controlling sheet 210 may be manufactured using either a roll-to-roll method, in which various processes are performed on a film transported from an upstream roll and then wound onto a downstream roll, or a sheet-to-sheet method, in which various processes are performed on a film cut to a specified size. In either case, the process of forming the grooves 2120 is performed before bonding the film consisting of the first transparent electrode layer 212A and the first transparent support layer 213A, and the film consisting of the second transparent electrode layer 212B and the second transparent support layer 213B, with the light-controlling layer 211 interposed therebetween.

Next, a cut is made in the corner of the second surface 211R of the light-adjusting sheet 210 of a predetermined size, and the second transparent support layer 213B and second transparent electrode layer 212B are peeled off. The light-adjusting layer 211 is then removed, exposing the first transparent electrode layer 212A to form the connection region 224. Similarly, the connection region 224 is also formed in the corner of the first surface 211F. Then, the first terminal portion 250A and the second terminal portion 250B are formed to connect the external wiring 225 to the connection region 224. The connection region 224 is then sealed with epoxy resin or the like. The process of bonding the protective layer 244 to the first transparent support layer 213A may be performed after the pair of films have been bonded together.

By forming the grooves 2120 by cutting into the first transparent electrode layer 212A and the first transparent support layer 213A in this way, the grooves 2120 can be formed more easily than with manufacturing methods that include, for example, steps required for patterning, such as forming a resist mask, exposing, developing, etching, removing the resist mask, and cleaning.

[Effect]
Next, the operation of this embodiment will be described with reference to Figure 37. Figure 37 schematically shows the degree of transparency of the light controlling sheet 210 when the light controlling sheet 210 is not driven, that is, when no voltage signal is applied to the first transparent electrode layer 212A and the second transparent electrode layer 212B. When the light controlling sheet 210 is not driven, both the driving area 220 and the non-driving area 221 are opaque. Therefore, the entire surface of the light controlling sheet 210 appears, for example, whitish or cloudy, and images such as letters and pictures formed in the non-driving area 221 are not visible.

Furthermore, because the grooves 2120 have a depth that penetrates the first transparent electrode layer 212A but does not penetrate the first transparent support layer 213A, the grooves 2120 are inconspicuous when viewed from either the first surface 211F or the second surface 211R of the light-adjusting sheet 210. In addition, by filling the grooves 2120 with a light-adjusting material, the grooves 2120 can be made even less visible. This enhances the aesthetic appearance of the light-adjusting sheet 210 when displaying a pattern.

As shown in Figure 31, when the light-adjusting sheet 210 is driven, the driven area 220 becomes transparent, while the non-driven area 221 remains opaque. Therefore, only the non-driven area 221 appears whitish or cloudy, for example, and the image of the pattern, such as letters or pictures, that is made up of the non-driven area 221 becomes visible.

As such, with the light-adjusting sheet 210 of this embodiment, regions with different light transmittances are formed within the surface of the light-adjusting sheet 210, and the difference in light transmittance between these regions only appears when the light-adjusting sheet 210 is driven. Therefore, when the light-adjusting sheet 210 is driven, images such as letters and pictures formed in the non-driven areas 221 are visible, making it possible to decorate the space in which the light-adjusting sheet 210 is placed. Furthermore, by switching between driving and non-driving the light-adjusting sheet 210, the appearance of the images can be switched on or off, allowing the decorative state of the space to be dynamically changed. This makes it possible to improve the design of the light-adjusting sheet 210.

As described above, the fourth embodiment of the light controlling sheet can provide the following effects.
(4-1) By applying a voltage signal to only one of the driving electrode elements 230 and the floating electrode elements 231, or by applying different voltage signals to the driving electrode elements 230 and the floating electrode elements 231, the light transmittance of the region in the light controlling sheet 210 where the driving electrode elements 230 are located and the region in which the floating electrode elements 231 are located can be changed. Therefore, it is possible to switch between a state in which there is no difference in light transmittance between the regions in which these electrode elements are located without applying a voltage signal to both the driving electrode elements 230 and the floating electrode elements 231, and a state in which there is a difference in light transmittance between the regions in which each electrode element is located, as described above, thereby improving the design of the light controlling sheet 210. Furthermore, because the grooves 2120 have a depth that penetrates the first transparent electrode layer 212A but does not penetrate the first transparent electrode layer 212A, the grooves 2120 can be made less noticeable when the light controlling sheet 210 is viewed from the first transparent electrode layer 212A side. This can improve the aesthetic appearance of the light controlling sheet 210. Furthermore, for example, the grooves 2120 can be formed more easily than by a method that includes a step of removing the first transparent electrode layer 212A by etching or the like.

(4-2) By filling at least a portion of the groove 2120 with a portion of the light-controlling layer 211, the groove 2120 can be made less visible when the light-controlling sheet 210 is viewed from the first transparent support layer 213A side or the second transparent support layer 213B side.

(4-3) By making the filling rate of the light-controlling material in the grooves 2120 80% or more, the grooves 2120 can be made less visible.
(4-4) By making the inner diameter of the opening 2122 of the groove 2120 smaller than the diameter of the spacer 215, it is possible to prevent the spacer 215 from entering the groove 2120. Therefore, the filling of the groove 2120 with the switchable layer 211 is less likely to be hindered by the spacer 215 that has entered the groove 2120.

(4-5) Because the height of the burrs 2123 present around the openings 2122 of the grooves 2120 is smaller than the thickness of the light-controlling layer 211, the tips of the burrs 2123 formed on the first transparent electrode layer 212A can be prevented from contacting the second transparent electrode layer 212B via the light-controlling layer 211. This makes it possible to prevent a short circuit from occurring between the first transparent electrode layer 212A and the second transparent electrode layer 212B.

(4-6) The groove 2120 has a closed frame shape that surrounds the floating electrode element 231. Therefore, since the closed frame shape allows the floating electrode element 231 to be partitioned, layout constraints for the floating electrode element 231 can be reduced.

[Modification of the fourth embodiment]
The above-described fourth embodiment can be modified as follows: In addition, the following modifications may be combined and implemented.

- In the above embodiment, the groove 2120 has a closed frame shape surrounding the floating electrode element 231. Alternatively, the groove 2120 does not have to have a closed frame shape surrounding the floating electrode element 231, as long as it extends along the support surface 2130 of the first transparent support layer 213A. For example, as shown in FIG. 38, when viewed from a position facing the first surface 211F, the boundary region 223 and groove 2120 may extend from a starting point located at the end 210E of the light control sheet 210, through the outer periphery of the floating region 222 and floating electrode element 231, to an ending point located at the end 210E of the light control sheet 210. In this case, the ends of the floating region 222 and floating electrode element 231 are located at the end 210E of the light control sheet 210. In Figure 38, the lower side of the rectangular light adjusting sheet 210 is shown as the end 210E, but the end 210E, which is the starting point and ending point of the boundary region 223 and groove 2120, may be the upper side, left side, or right side, or may be any of multiple sides.

- In the above embodiment, the light-adjusting sheet 210 is of a normal type, but it may also be of a reverse type. A reverse-type light-adjusting sheet 210 transmits incident light when no voltage signal is applied, increasing its translucency, and scatters incident light when a voltage signal is applied, decreasing its translucency.

Figure 39 shows an example of a reverse-type light-controlling sheet 210. As shown in Figure 39, the light-controlling layer 211 of the reverse-type light-controlling sheet 210 has a multilayer structure and includes a functional layer 2111 comprising a transparent polymer layer and a liquid crystal composition, a first alignment layer 2112, and a second alignment layer 2113. The functional layer 2111, the first alignment layer 2112, and the second alignment layer 2113 constitute the light-controlling layer 211. The first alignment layer 2112 is located between the functional layer 2111 and the first transparent electrode layer 212A and is in contact with these layers. The second alignment layer 2113 is located between the functional layer 2111 and the second transparent electrode layer 212B and is in contact with these layers.

Each of the first alignment layer 2112 and the second alignment layer 2113 is, for example, a vertical alignment film. The vertical alignment film aligns the long axis direction of the liquid crystal molecules along the thickness direction of the light control layer 211. The material for forming each of the first alignment layer 2112 and the second alignment layer 2113 may be any of the materials listed in the first embodiment.

The groove 2120 has an opening 2122 on the side of the first alignment layer 2112 facing the light-controlling layer 211, and penetrates the first alignment layer 2112 and the first transparent electrode layer 212A, but not the first transparent support layer 213A. In other words, the depth of the groove 2120 is smaller than the sum of the thicknesses of the first alignment layer 2112, the first transparent electrode layer 212A, and the first transparent support layer 213A. A portion of the light-controlling layer 211 is filled into the groove 2120.

When the light-controlling sheet 210 includes the first alignment layer 2112 and the second alignment layer 2113, in the driving region 220, when no voltage signal is applied to the transparent electrode layers 212A and 212B, the long axis direction of the liquid crystal molecules is aligned along the thickness direction of the light-controlling layer 211. Therefore, the driving region 220 is transparent. On the other hand, when a voltage signal is applied to the transparent electrode layers 212A and 212B in the driving region 220, the long axis direction of the liquid crystal molecules is aligned across the thickness direction of the light-controlling layer 211. Therefore, the driving region 220 appears cloudy and opaque. When the light-controlling sheet 210 includes the first alignment layer 2112 and the second alignment layer 2113, in the floating region 222 and the boundary region 223, the long axis direction of the liquid crystal molecules is always aligned along the thickness direction of the light-controlling layer 211, so the non-driving region 221 is always transparent.

Therefore, when the light-adjusting sheet 210 is not driven, both the driving area 220 and the non-driving area 221 are transparent, and images such as letters and patterns made up of the non-driving area 221 are not visible. On the other hand, when the light-adjusting sheet 210 is driven, the driving area 220 becomes opaque, while the non-driving area 221 is transparent, so images such as letters and patterns made up of the non-driving area 221 become visible.

In this way, even when the light-controlling sheet 210 includes the first alignment layer 2112 and the second alignment layer 2113, regions with different light transmittances are formed within the surface of the light-controlling sheet 210, and the difference in light transmittance between these regions only appears when the light-controlling sheet 210 is driven. This makes it possible to improve the design of the light-controlling sheet 210.

In addition, in the above embodiment, the grooves 2120 penetrate the first alignment layer 2112, but the grooves 2120 may be formed in a laminate consisting of the first transparent electrode layer 212A and the first transparent support layer 213A, and then the first alignment layer 2112 may be formed. In this case, the first alignment layer 2112 is formed so as to follow the bottom and side surfaces of the grooves 2120. This also makes it possible to make the grooves 2120 less noticeable when viewed from the outside.

In the above embodiment, a voltage signal is applied to the driving electrode element 230, which is the first electrode element, and no voltage signal is applied to the floating electrode element 231, which is the second electrode element. Alternatively, voltage signals may be applied separately to the first electrode element and the second electrode element. In this case, wiring for applying a voltage signal to the second electrode element is connected to the end of the second electrode element. The terminal portion connected to the first electrode element and the terminal portion connected to the second electrode element are separate terminal portions for each voltage signal. As described above, if the second electrode element is located at the end of the light control sheet 210, it is easy to connect wiring to the second electrode element.

For example, the first region where the first electrode elements are located can be switched between transparent and opaque by switching the state of a voltage signal applied to the first electrode elements. The second region where the second electrode elements are located can be switched between transparent and opaque, independently of the first region, by switching the state of a voltage signal applied to the second electrode elements. This configuration makes it possible to switch between four states: a state where both the first and second regions are opaque, a state where the first region is opaque and the second region is transparent, a state where the first region is transparent and the second region is opaque, and a state where both the first and second regions are opaque. This allows for a more diverse range of changes to the decorative state of a space using the light-controlling sheet 210, further improving the design of the light-controlling sheet 210.

The light transmittance of at least one of the first and second regions may be controlled to a light transmittance that corresponds between transparency and opacity. In a light-controlling sheet 210 having a light-controlling layer 211 containing a liquid crystal composition, when the potential difference between the transparent electrode layers 212A and 212B is within a predetermined range, the light transmittance of the light-controlling sheet 210 gradually changes as the potential difference changes. Therefore, by controlling the potential difference between the transparent electrode layers 212A and 212B in the first or second region to a value between the potential difference at which the region becomes transparent and the potential difference at which the region becomes opaque, the region can be controlled to be translucent, with a light transmittance that corresponds between transparency and opacity.

Specifically, for example, the first region can be switched between transparent and opaque by switching the state of a voltage signal applied to the first electrode element, and the second region can be switched between translucent and opaque by switching the state of a voltage signal applied to the second electrode element. When the first region is transparent, the second region is controlled to be translucent. With this configuration, it is possible to switch between a state in which both the first and second regions are opaque, and a state in which the first region is opaque and the second region is translucent. This also makes it possible to improve the design of the light-controlling sheet 210.

Fifth Embodiment
A fifth embodiment of the light controlling sheet will be described with reference to Figures 40 to 47. The light controlling sheet 310 of this embodiment is a normal type. The normal type light controlling sheet 310 increases the scattering of incident light in the region to be driven when no voltage signal is applied to the light controlling sheet 310, and decreases the scattering when a voltage signal is applied to the light controlling sheet 310.

[Light control sheet]
The planar structure of the light controlling sheet 310 will be described with reference to FIG.
40 , the light controlling sheet 310 has a first surface 311F and a second surface 311R that is the surface opposite to the first surface 311F. The light controlling sheet 310 has a driving region 320 and a non-driving region 321.

The light-controlling sheet 310 has a laminated structure. The driving region 320 is a region that includes the driving electrode element 330 as part of the laminated structure. The driving electrode element 330 is an electrode element to which a voltage signal is applied when the light-controlling sheet 310 is driven. The diffuse transmittance of the driving region 320 changes depending on the state of the voltage signal applied to the driving electrode element 330. The driving electrode element 330 is an example of a first electrode element. The non-driving region 321 is a region that includes the floating electrode element 331 as part of the laminated structure. The floating electrode element 331 is an electrode element to which a voltage signal is not applied when the light-controlling sheet 310 is driven. The floating electrode element 331 is an example of a second electrode element. The diffuse transmittance of the driving region 320 changes depending on the state of the voltage signal applied to the light-controlling sheet 310, while the diffuse transmittance of the non-driving region 321 does not change depending on the state of the voltage signal applied to the light-controlling sheet 310. In the example shown in Figure 40, the non-driving region 321 is arranged along the pattern. The design may be, for example, one or a combination of two or more of letters, numbers, symbols, figures, pictures, patterns, etc.

The non-drive region 321 shown in Figure 40 has a shape like a long, thin line. The non-drive region 321 is bent at multiple points between the first end 321A and the second end 321B. The non-drive region 321 divides the drive region 320 into a second drive region 320B having a predetermined pattern shape and a first drive region 320A located outside the second drive region 320B. Furthermore, in the non-drive region 321, parts of the non-drive region 321 do not contact or intersect with other parts between the first end 321A and the second end 321B, and a distance of at least a predetermined distance is maintained between parts of the non-drive region 321 throughout the entire non-drive region 321. In the example shown in Figure 40, even in region 3101 where one part of the non-drive region 321 is close to another part, a distance is maintained between parts of the non-drive region 321.

Each driving region 320A, 320B defined by the non-driving region 321 is electrically connected via a narrowed portion 330A sandwiched between the groove 3120 (see FIG. 42), i.e., located between the first and second portions of the groove 3120. The narrowed portion 330A is an example of an inter-groove region. In other words, the driving electrode element 330 includes a narrowed portion 330A included in a conductive portion 326. The conductive portion 326 is sandwiched between the first and second portions of the non-driving region 321, which includes the groove 3120 and the floating electrode element 331, and connects the first driving region 320A to the second driving region 320B. The width of the conductive portion 326, i.e., the width of the narrowed portion 330A, is narrower than the widths of the driving regions 320A, 320B. The non-driving region 321 and the conductive portion 326 surround the second driving region 320B. The first drive region 320A is an example of an outer region, and the second drive region 320B is an example of an inner region.

The light-adjusting sheet 310 has two connection regions 324. The connection regions 324 are regions for applying voltage signals to the driving regions 320. External wiring 325 is connected to the connection regions 324. The connection regions 324 and the driving regions 320 are adjacent to each other, thereby connecting the driving regions 320 to the connection regions 324.

One connection region 324 is the first connection region 324A, and the other connection region 324 is the second connection region 324B. The second connection region 324B is exposed to the outside of the light controlling sheet 310 when viewed from a viewpoint facing the first surface 311F of the light controlling sheet 310. The first connection region 324A is exposed to the outside of the light controlling sheet 310 when viewed from a viewpoint facing the second surface 311R of the light controlling sheet 310. The first connection region 324A and the second connection region 324B are aligned along the edge of the light controlling sheet 310. The direction in which the first connection region 324A and the second connection region 324B are aligned is the first direction.

When a voltage signal is applied to the light-adjusting sheet 310 via the connection region 324, the diffuse transmittance of the driving regions 320A and 320B becomes lower than when no voltage signal is applied to the light-adjusting sheet 310. On the other hand, the diffuse transmittance of the non-driving region 321 does not change even when a voltage signal is applied to the light-adjusting sheet 310. As a result, a pattern 3100 defined by the linear non-driving region 321 appears on the light-adjusting sheet 310. At this time, the diffuse transmittance is lowered in the second driving region 320B surrounded by the non-driving region 321, so the so-called "white-out" pattern 3100 is displayed. Note that while the light-adjusting sheet 310 shown in Figure 40 displays a single pattern using the non-driving region 321, multiple patterns may also be displayed. In other words, the light-adjusting sheet 310 may have multiple independent non-driving regions 321 that are not connected to each other.

The layered structure of the light-controlling sheet 310 will be described with reference to Figures 41 and 42. Figure 41 is a cross-sectional view taken along line V-V in Figure 40, showing the cross-sectional structure of the light-controlling sheet 310 in part of the drive region 320 and the connection region 324. Note that the thickness ratios of the layers in Figure 41 are shown for convenience of explanation, and the thickness ratios of the layers are not limited to those shown in the figure. Also, for convenience of illustration, Figure 41 omits the illustration of the antiviral film provided on the light-controlling sheet 310. The light-controlling sheet 310 of the fifth embodiment can be provided with the antiviral film provided on the light-controlling sheet of the first embodiment, as well as the antiviral film or antiviral layer described in the modified example of the first embodiment.

As shown in Figure 41, the light-controlling sheet 310 has a light-controlling layer 311, a first transparent electrode layer 312A, a second transparent electrode layer 312B, a first transparent support layer 313A, and a second transparent support layer 313B. The light-controlling layer 311 is sandwiched between the first transparent electrode layer 312A and the second transparent electrode layer 312B. The first transparent support layer 313A supports the surface of the first transparent electrode layer 312A opposite to the surface that contacts the light-controlling layer 311 with a support surface 3130, which is a single continuous surface. The second transparent support layer 313B supports the surface of the second transparent electrode layer 312B opposite to the surface that contacts the light-controlling layer 311. The light-controlling layer 311 may have a single-layer structure or a multi-layer structure. The multilayered light control layer 311 may include, for example, a functional layer having a light control function and a functional layer that improves adhesion between the functional layer and the first transparent electrode layer 312A and between the functional layer and the second transparent electrode layer 312B.

The light-controlling sheet 310 further includes a protective layer 344. The protective layer 344 is located on the opposite side of the first transparent support layer 313A from the first transparent electrode layer 312A. The protective layer 344 may be fixed to the first transparent support layer 313A via an adhesive layer (not shown). If the light-controlling sheet 310 includes an antiviral film, the light-controlling sheet 310 may include the antiviral film instead of the protective layer 344 and adhesive layer. Alternatively, the light-controlling sheet 310 may include an antiviral film on the protective layer 344. In this case, the adhesive layer of the antiviral film contacts the protective layer 344.

The first surface 311F of the light-controlling sheet 310 is the surface of the protective layer 344 opposite the surface facing the first transparent support layer 313A. The second surface 311R of the light-controlling sheet 310 is the surface of the second transparent support layer 313B opposite the surface facing the second transparent electrode layer 312B. The second surface 311R is attached to a transparent plate made of glass, resin, or the like via an adhesive layer (not shown). Examples of transparent plates include windowpanes in various buildings such as homes, stores, stations, and airports; partitions installed in offices, medical institutions, and nursing homes; shop windows installed in stores; and windowpanes or windshields in moving objects such as vehicles and aircraft. Each surface of the transparent plate may be flat or curved. If the light-controlling sheet 310 includes an antiviral film, the adhesive layer of the antiviral film is located on the second surface 311R of the light-controlling sheet 310, and the antiviral film is attached to the transparent plate.

As described above, the connection region 324 includes the first connection region 324A and the second connection region 324B. The first connection region 324A is connected to external wiring 325 for applying a voltage signal to the first transparent electrode layer 312A. The second connection region 324B is connected to external wiring 325 for applying a voltage signal to the second transparent electrode layer 312B.

The light control layer 311, second transparent electrode layer 312B, and second transparent support layer 313B are not located in the first connection region 324A, leaving a portion of the first transparent electrode layer 312A exposed to the outside. The first terminal 350A is connected to the portion of the first transparent electrode layer 312A exposed in the first connection region 324A. That is, the driving electrode element 330 extends from the driving region 320 to the first connection region 324A, and the first terminal 350A is connected to the driving electrode element 330 in the first connection region 324A. That is, the first transparent electrode layer 312A includes the driving electrode element 330, the driving region 320 includes a portion of the driving electrode element 330, and the first connection region 324A includes another portion of the driving electrode element 330.

The second connection region 324B does not include the light control layer 311, first transparent electrode layer 312A, first transparent support layer 313A, or protective layer 344, leaving a portion of the second transparent electrode layer 312B exposed. The second terminal portion 350B is connected to the portion of the second transparent electrode layer 312B exposed in the second connection region 324B.

An external wiring 325 is connected to each of the first terminal 350A and the second terminal 350B. Each external wiring 325 is connected to the control unit 350. The control unit 350 applies a voltage signal to the drive electrode element 330 of the first transparent electrode layer 312A through the first terminal 350A, and applies a voltage signal to the second transparent electrode layer 312B through the second terminal 350B. In this way, the control unit 350 controls the potential difference between the first transparent electrode layer 312A and the second transparent electrode layer 312B in the drive region 320. The second transparent electrode layer 312B is controlled to, for example, ground potential. The light control sheet 310 and the control unit 350 constitute a light control device.

The light-controlling layer 311 comprises a transparent polymer layer and a liquid crystal composition. The transparent polymer layer has voids into which the liquid crystal composition is filled. The liquid crystal composition fills the voids in the transparent polymer layer. The liquid crystal composition contains liquid crystal molecules. The liquid crystal molecules may be any of the liquid crystal molecules listed in the first embodiment. When the light-controlling layer 311 has a single-layer structure, the light-controlling layer 311 consists only of a functional layer comprising a transparent polymer layer and a liquid crystal composition.

The retention type of the liquid crystal composition may be any of the retention types listed in the first embodiment. As with the first embodiment, the liquid crystal composition may contain, in addition to the liquid crystal molecules described above, a monomer for forming a transparent polymer layer, a dichroic dye, and the like. In the example shown in Figure 41, the light-controlling layer 311 includes a spacer 315. The spacer 315 maintains the thickness of the light-controlling layer 311 within a certain range.

Each of the first transparent electrode layer 312A and the second transparent electrode layer 312B is conductive and transparent to light in the visible range. The materials used to form the first transparent electrode layer 312A and the second transparent electrode layer 312B may be any of the materials listed in the first embodiment.

Each of the first transparent support layer 313A and the second transparent support layer 313B is a substrate that is transparent to light in the visible region. The materials used to form the first transparent support layer 313A and the second transparent support layer 313B may be any of the materials listed in the first embodiment.

Each of the first terminal portion 350A and the second terminal portion 350B includes, for example, a conductive adhesive layer and a wiring substrate. The conductive adhesive layer may be any of the adhesive layers listed in the first embodiment. As in the first embodiment, the wiring substrate may be, for example, a flexible printed circuit (FPC). Alternatively, each of the first terminal portion 350A and the second terminal portion 350B may be made of a conductive material such as conductive tape, as in the first embodiment. If the first terminal portion 350A and the second terminal portion 350B are made of conductive tape, the external wiring 325 may be soldered to the first terminal portion 350A and the second terminal portion 350B.

In the driving region 320, in the portion of the dimming layer 311 included in the driving region 320, the orientation of the liquid crystal molecules changes in response to changes in the voltage generated between the first transparent electrode layer 312A and the second transparent electrode layer 312B. The change in orientation of the liquid crystal molecules changes the degree of scattering, absorption, and transmission of visible light entering the dimming layer 311. Specifically, when no voltage signal is applied to the first transparent electrode layer 312A and the second transparent electrode layer 312B of the driving region 320, the orientation of the long axis direction of the liquid crystal molecules is irregular. As a result, the degree of scattering of light incident on the dimming layer 311 increases, and the driving region 320 appears cloudy. In other words, when no voltage signal is applied to the dimming layer 311, the driving region 320 is opaque. On the other hand, when a voltage signal is applied to first transparent electrode layer 312A and second transparent electrode layer 312B, creating a potential difference of a predetermined value or greater between first transparent electrode layer 312A and second transparent electrode layer 312B, the liquid crystal molecules are oriented, with their major axes oriented along the electric field direction between first transparent electrode layer 312A and second transparent electrode layer 312B. As a result, light can more easily pass through dimming layer 311, i.e., diffusion in dimming layer 311 is suppressed, and drive region 320 appears transparent.

42 shows a cross-sectional structure taken along line VI-VI in FIG. 40. This cross-sectional structure includes the cross-sectional structure of the non-driving region 321.
As shown in Figure 42, the driving region 320 includes driving electrode elements 330 that are part of the first transparent electrode layer 312A. The non-driving region 321 includes a floating region 322 in which the floating electrode elements 331 are located and a boundary region 323 in which the grooves 3120 are located. The grooves 3120 surround the outer edge of the floating electrode elements 331. The boundary region 323 does not include the driving electrode elements 330 and the floating electrode elements 331. The floating region 322 is defined by the boundary region 323 made of the grooves 3120. The driving electrode elements 330 and the floating electrode elements 331 are separate layered bodies that are aligned along the support surface 3130 of the first transparent support layer 313A. In the first transparent electrode layer 312A, the grooves 3120 and the floating electrode elements 331 constitute non-driving elements. Of the drive electrode elements 330, the portions included in the first drive region 320A are first drive electrode elements, and the portions included in the second drive region 320B are second drive electrode elements.

The driving electrode element 330 and the floating electrode element 331 are separated by a groove 3120. In this embodiment, the groove 3120 has an opening 3122 on the surface of the first transparent electrode layer 312A that contacts the light control layer 311. The groove 3120 penetrates the first transparent electrode layer 312A and extends partway through the thickness direction of the first transparent support layer 313A. The driving electrode element 330 and the floating electrode element 331 are insulated from each other by being separated by the groove 3120.

The width L2 of the groove 3120 may be smaller than the diameter of the spacer 315. This prevents the spacer 315 from entering the groove 3120. The groove 3120 is filled with a liquid crystal composition. The liquid crystal composition need only fill a portion of the groove 3120, and does not have to fill the entire groove 3120. By filling the groove 3120 with the liquid crystal composition, the groove 3120 is less noticeable when the light controlling sheet 310 is viewed from a viewpoint facing the first surface 311F or a viewpoint facing the second surface 311R while the light controlling sheet 310 is not driven. In other words, because the liquid crystal composition is located within the groove 3120, it is possible to reduce the difference in diffuse transmittance between the groove 3120 and portions of the light controlling sheet 310 other than the groove 3120 when no voltage is applied between the transparent electrode layers 312A and 312B. This prevents the groove 3120 from being visible.

The non-driven region 321 will be described with reference to Figures 43 and 44. Figure 43 is an enlarged view of the region 3101 in Figure 40.
43 , the conductive portion 326 including the narrowed portion 330A may be positioned so as to connect the first portion and the second portion of the non-driving region 321. Alternatively, the conductive portion 326 may be provided between the first end 321A and the second end 321B. From the viewpoint of ensuring conductivity between the first driving region 320A outside the non-driving region 321 and the second driving region 320B within the non-driving region 321, the width L1 of the narrowed portion 330A included in the conductive portion 326 may be 1 mm or more.

In the example shown in FIG. 43, the width L1 between the first end 321A of the non-driving region 321 and the opposing portion of the non-driving region 321 that is the closest to the first end 321A may be 1 mm or more in the direction in which the first end 321A and the opposing portion are aligned. That is, in the non-driving region 321, the first portion and the second portion are separated from each other by a portion of the driving region 320. The portion of the driving region 320 that separates the first portion and the second portion of the non-driving region 321 is the conductive portion 326 including the narrowed portion 330A. The narrowed portion 330A is located between a portion of the groove 3120 that surrounds a portion of the floating electrode element 331 included in the first portion and a portion of the groove 3120 that surrounds a portion of the floating electrode element 331 included in the second portion.

By making the width L1 of the narrowing portion 330A 1 mm or more, an increase in the resistance value of the narrowing portion 330A is suppressed, thereby preventing the diffuse transmittance of the driving regions 320A and 320B from becoming equal when a driving voltage is applied. For example, this prevents the second driving region 320B from changing from an opaque state to a transparent state even when a driving voltage is applied. Furthermore, when a white pattern 3100 such as that shown in Figure 40 is displayed on the light controlling sheet 310, from the perspective of enhancing the design, the width L1 of the narrowing portion 330A may be 30 mm or less. By making the width L1 of the narrowing portion 330A 30 mm or less, the desired pattern is more easily displayed.

The narrowed portion 330A is an example of an inter-groove region, and is a portion of the first transparent electrode layer 312A that is constricted by the groove 3120 that defines the narrowed portion 330A. The peel strength between the narrowed portion 330A and the second transparent electrode layer 312B may be 0.01 N or greater. The peel strength is a value measured in accordance with 6.9.3 a) 180-degree peel test of JIS A 5759:2016 "Films for Architectural Window Glass." Because the peel strength between the narrowed portion 330A and the second transparent electrode layer 312B is 0.01 N or greater, it is possible to suppress peeling in the portion of the light control sheet 310 that includes the narrowed portion 330A. As a result, even when the first transparent electrode layer 312A is patterned so that a narrowed portion 330A sandwiched between grooves 3120 is formed in the first transparent electrode layer 312A, poor conductivity due to peeling can be suppressed, thereby improving the design of the light control sheet 310.

When the width of the narrowed portion 330A is 2 mm or more, the peel strength between the narrowed portion 330A and the second transparent electrode layer 312B per unit length in the width direction of the narrowed portion 330A may be 0.1 N/10 mm. Because the peel strength between the narrowed portion 330A and the second transparent electrode layer 312B per unit length is 0.1 N/10 mm or more, when the light-controlling sheet 310 has a narrowed portion 330A with a width of 2 mm or more, peeling is suppressed in the portion including the narrowed portion 330A.

The peel strength between the inter-groove region and the second transparent electrode layer can be changed, for example, by changing the mechanical strength of the transparent polymer layer contained in the light-controlling layer 311. The light-controlling sheet 310 tends to have a higher peel strength the higher the mechanical strength of the transparent polymer layer. The mechanical strength of the transparent polymer layer can be increased by increasing the ratio of the mass of the polymerizable composition to the mass of the liquid crystal in the light-controlling material used to form the light-controlling layer 311. The light-controlling sheet 310 also tends to have a higher peel strength the higher the adhesion between the transparent polymer layer and the transparent film containing the transparent electrode layer.

The non-driven region 321 also has a bent portion 3102 according to the pattern 3100. The bent portion 3102 is a curved or bent portion. As shown in Figure 43, when the bent portion 3102 of the non-driven region 321 is curved, the minimum value of the first angle θ1 formed by the first tangent 3105 and the second tangent 3106 of the bent portion 3102 may be 10 degrees or greater. The first tangent 3105 is a tangent that touches the first portion of the bent portion 3102 on the outside of the bent portion 3102, and the second tangent 3106 is a tangent that touches the second portion of the bent portion 3102 on the outside of the bent portion 3102. The first and second portions are set at the bent portion so as to sandwich a bending point included in the bent portion 3102. Furthermore, the first and second portions are set so that no part of the drive region 320 is sandwiched between the first and second portions.

As shown in FIG. 44, the non-drive region 321 may include a bent portion 3102 composed of two straight portions that sandwich a bend point. The two straight portions are a first straight portion and a second straight portion. In the bent portion 3102, a portion of the drive region 320 is sandwiched between the first straight portion and the second straight portion. The minimum value of the second angle θ2 formed by the first straight portion and the second straight portion may be 10 degrees or greater. Note that the second angle θ2 is the angle formed on the inside of the bent portion 3102 between a portion of the groove 3120 included in the first straight portion and a portion of the groove 3120 included in the second straight portion.

If the first angle θ1 and the second angle θ2 are less than 10 degrees, there is a possibility that the first transparent support layer 313A and the first transparent electrode layer 312A will peel off from the adjacent layers during or after the process of forming the grooves 3120. In contrast, if the first angle θ1 and the second angle θ2 are 10 degrees or greater, peeling of the first transparent support layer 313A and the first transparent electrode layer 312A can be suppressed, and the pattern formed by the non-driven areas 321 can be made clearer.

In the region surrounded by the bent portion 3102 shown in Figure 44, the groove 3120 has a groove bend portion 120GB. The groove bend portion 120GB is the portion of the groove 3120 where the first groove portion GB1 and the second groove portion GB2 are folded back at the bend point GB3. The groove bend portion 120GB may include a portion where the width of the groove bend portion 120GB, i.e., the width of the inter-groove region, is 1 mm or more.

The width of the inter-groove region is defined as follows. As in the example shown in Figure 44, when the first groove portion GB1 and the second groove portion GB2 are linear, first, a first imaginary line along the first groove portion GB1 and a second imaginary line along the second groove portion GB2 are defined. The distance between the first imaginary line and the second imaginary line in a direction perpendicular to the bisector that bisects the apex angle of the triangle formed by the first imaginary line and the second imaginary line is the width of the inter-groove region.

In contrast, when at least one of the first groove portion GB1 and the second groove portion GB2 has a curved shape, the distance between the first groove portion GB1 and the second groove portion GB2 on a straight line extending in the normal direction of the curved groove portion is the width of the inter-groove region.

In the groove bend portion 120GB, as in the narrowed portion 330A, the peel strength between the inter-groove region and the second transparent electrode layer 312B may be 0.01 N or greater. By ensuring that the peel strength between the inter-groove region and the second transparent electrode layer 312B is 0.01 N or greater, it is possible to prevent peeling from occurring in the portion of the light control sheet 310 that includes the inter-groove region sandwiched between the groove bend portion 120GB.

The inter-groove region may also include a portion where the width of the inter-groove region is 2 mm or more. In this portion, the peel strength per unit length in the width direction of the inter-groove region between the inter-groove region and the second transparent electrode layer 312B may be 0.1 N/10 mm. Peeling between the inter-groove region and the second transparent electrode layer 312B is suppressed in at least a portion of the light-controlling sheet 310 that includes the inter-groove region. This causes the optical properties of at least a portion of the light-controlling sheet 310 that includes the inter-groove region to change depending on whether or not a voltage is applied between the transparent electrode layers 312A and 312B, thereby enhancing the design of the light-controlling sheet 310.

On the other hand, the first transparent electrode layer 312A has a conductive region in addition to the grooves 3120 and the inter-groove regions. The conductive region is a region that is wider than the inter-groove regions. In other words, the conductive region is a region that does not include a portion having a width smaller than the width of the inter-groove regions. In the example shown in Figure 44, the portion of the first transparent electrode layer 312A that is included in the first drive region 320A is the conductive region. The peel strength between the conductive region and the second transparent electrode layer 312B may be 0.38 N/25 mm or more.

The peel strength between the conductive area and the second transparent electrode layer 312B is 0.38 N/25 mm, which prevents peeling from the second transparent electrode layer 312B even in the groove areas, which are narrower than the conductive area. This reduces poor conductivity caused by peeling in the light-adjusting sheet, thereby improving the design of the light-adjusting sheet.

FIG. 45 shows an enlarged view of an area including the first connection area 324A and part of the non-drive area 321 in the light controlling sheet 310.
As shown in Figure 45, the first connection region 324A includes a first terminal 350A that applies a voltage to the first transparent electrode layer 312A. The first connection region 324A is bordered by a portion of the first transparent electrode layer 312A that is exposed from the light control layer 311. Similar to the first connection region 324A, the second connection region 324B also includes a second terminal 350B that applies a voltage to the second transparent electrode layer 312B (see Figure 41). Similar to the first connection region 324A, the second connection region 324B is bordered by a portion of the second transparent electrode layer 312B that is exposed from the light control layer 311.

The first line SL1 is a line that extends along the first direction in which the first connection region 324A and the second connection region 324B are aligned and passes through the first connection region 324A. The second line SL2 is a line that passes through the groove in the first direction. The shortest distance D between the first line SL1 and the second line SL2 may be 5 mm or more and 50 mm or less.

The shortest distance D between the first line SL1 passing through the first connection region and the second line SL2 passing through the groove 3120 is 5 mm or more. Therefore, even if the floating electrode element 331 is placed near the first connection region 324A, where the shortest distance D is 50 mm or less, an increase in resistance is suppressed in the portion of the drive electrode element 330 located between the first connection region 324A and the floating electrode element 331. This prevents a decrease in the effective voltage applied to the portion of the drive electrode element 330 that is farther away from the first connection region 324A than the floating electrode element 331. This makes it possible to change the optical properties of the entire light controlling sheet 310 by applying or not applying a voltage between the transparent electrode layers 312A and 312B, thereby enhancing the design of the light controlling sheet 310.

In the first transparent electrode layer 312A, an area adjacent to the first connection area 324A is a unit area. The unit area extends along the first direction and is separated from the first connection area 324A by a first straight line SL1 passing through the first connection area 324A. The length of the unit area in the first direction is 100 mm, and the length of the unit area in a second direction perpendicular to the first direction is 100 mm. In the unit area, the percentage {100 x A2/(A1 + A2)} of the area of the floating electrode element 331 to the sum (A1 + A2) of the area of the drive electrode element 330 (A1) and the area of the floating electrode element 331 may be 30% or greater. This enhances the effectiveness of having the shortest distance D between the first straight line SL1 passing through the first connection area 324A and the second straight line SL2 passing through the groove 3120 be 5 mm or greater.

[Method of manufacturing light controlling sheet]
An example of a method for manufacturing the light controlling sheet 310 will be described with reference to FIG.
First, a first film 351A and a second film 351B are prepared. The first film 351A includes a first transparent electrode layer 312A and a first transparent support layer 313A. The second film 351B includes a second transparent electrode layer 312B and a second transparent support layer 313B.

For the first film 351A, grooves 3120 are formed using a cutting plotter on the surface of the first transparent electrode layer 312A opposite the surface that contacts the first transparent support layer 313A. A control device connected to the cutting plotter operates the cutting plotter according to a design that has been input into the control device in advance, thereby forming grooves 3120 that penetrate the first transparent electrode layer 312A and extend partway through the thickness of the first transparent support layer 313A.

It should be noted that the grooves 3120 may be formed using a device other than a cutting plotter. For example, the grooves 3120 may be formed in the first transparent electrode layer 312A using a blade other than a cutting plotter or a laser cutting device. The laser cutting device may be, for example, a laser equipped with a _CO2 laser. When a laser cutting device is used, the portions of the first transparent electrode layer 312A and the first transparent support layer 313A irradiated with laser light are directly destroyed, thereby forming the grooves 3120.

Next, a liquid containing spacers 315, primarily made of divinylbenzene or the like, and a dispersion medium for dispersing the spacers 315 is prepared. The liquid is then applied to the first transparent electrode layer 312A of the first film 351A and the second transparent electrode layer 312B of the second film 351B. This spreads the spacers 315 over the first transparent electrode layer 312A and the second transparent electrode layer 312B. Furthermore, the films 351A and 351B onto which the spacers 315 have been spread are heated, thereby removing the dispersion medium from the liquid. Note that the spacers 315 may be spread only over either the first film 351A or the second film 351B.

Then, a light-controlling material containing a liquid crystal composition and a polymerizable composition for forming a transparent polymer layer is applied to the first transparent electrode layer 312A and the second transparent electrode layer 312B. Furthermore, the films 351A and 351B are irradiated with ultraviolet light in a nitrogen atmosphere, thereby forming light-controlling layers 311A and 311B. Next, the second film 351B is laminated onto the first film 351A while applying a predetermined amount of pressure to the laminate obtained by laminating the second film 351B onto the first film 351A so that the light-controlling layers 311A and 311B are in contact with each other. This fills the grooves 3120 with at least a portion of the liquid crystal composition. The grooves 3120 may also be filled with both a portion of the transparent polymer layer and a portion of the liquid crystal composition.

The light-modulating sheet 310 may be manufactured using either a roll-to-roll method or a sheet-fed method. With the roll-to-roll method, the film is pulled out from an upstream roll and various processes are performed on it while it is being transported, and then the processed film is wound up onto a downstream roll. With the sheet-fed method, various processes are performed on film that has been cut to a specified size. In either case, the process of forming grooves 3120 in the first film 351A is performed before the process of bonding the second film 351B to the first film 351A with the light-modulating layer 311 interposed between them.

Next, a corner of the second surface 311R of the light-controlling sheet 310 having a predetermined size is cut to peel off a portion of the second transparent support layer 313B and a portion of the second transparent electrode layer 312B. This exposes a portion of the light-controlling layer 311 to the outside. The exposed portion of the light-controlling layer 311 is then removed to expose a portion of the first transparent electrode layer 312A, thereby forming the first connection region 324A. Similarly, a second connection region 324B is formed at the corner of the first surface 311F. Then, a first terminal portion 350A is formed in the first connection region 324A, and a second terminal portion 350B is formed in the second connection region 324B. Next, external wiring 325 is connected to each terminal portion 350A, 350B. The connection region 324 is then sealed with epoxy resin or the like. The step of bonding the protective layer 344 to the first transparent support layer 313A may be performed after bonding the pair of films 351A and 351B together, or may be performed before bonding the films 351A and 351B together.

In this way, the grooves 3120 are formed by cutting the first transparent electrode layer 312A and the first transparent support layer 313A. Therefore, compared to manufacturing methods that include steps such as forming a resist mask, etching, removing the resist mask, and cleaning, which are required for patterning, the grooves 3120 can be formed more easily.

[Effect]
The operation of this embodiment will be described with reference to Figures 40 and 47. Figure 47 schematically shows the degree of transparency of the light controlling sheet 310 when the light controlling sheet 310 is not driven, that is, when no voltage signal is applied to the first transparent electrode layer 312A and the second transparent electrode layer 312B.

As shown in Figure 47, when the light-adjusting sheet 310 is not driven, both the driven area 320 and the non-driven area 321 are opaque. Therefore, the entire surface of the light-adjusting sheet 310 appears, for example, whitish and cloudy, and images such as letters and pictures made up of the non-driven area 321 are not visible.

Furthermore, because the grooves 3120 have a depth that penetrates the first transparent electrode layer 312A but does not penetrate the first transparent support layer 313A, the grooves 3120 are inconspicuous whether the light controlling sheet 310 is viewed from the first surface 311F or the second surface 311R. In addition, by filling the grooves 3120 with at least a liquid crystal composition of the light controlling material, the grooves 3120 can be made even less visible when the light controlling sheet 310 is not driven. This improves the aesthetic appearance of the light controlling sheet 310 when no pattern is displayed.

As shown in Figure 40, when the light-adjusting sheet 310 is driven, the driving area 320 appears transparent, while the non-driving area 321 appears opaque. Therefore, only the non-driving area 321 appears, for example, whitish and cloudy, and the image of the pattern, such as letters or pictures, made up of the non-driving area 321 is visible. At this time, a voltage signal is applied to the second driving area 320B surrounded by the non-driving area 321 and the first driving area 320A outside the non-driving area 321, causing the driving areas 320A and 320B to appear transparent.

As such, with the light-adjusting sheet 310 of this embodiment, regions with different diffuse transmittances are formed within the surface of the light-adjusting sheet 310, and the difference in diffuse transmittance between these regions only appears when the light-adjusting sheet 310 is driven. Therefore, when the light-adjusting sheet 310 is driven, images such as letters and patterns formed in the non-driven regions 321 are visible. This makes it possible to improve the design of the light-adjusting sheet 310.

In addition, the image displayed by the light-adjusting sheet 310 can be used to decorate the space in which the light-adjusting sheet 310 is installed. Furthermore, by switching the light-adjusting sheet 310 between driven and de-driven states, the appearance of the image can be switched on or off, allowing for dynamic changes to the decorative state of the space.

As described above, the fifth embodiment of the light controlling sheet can provide the following effects.
(5-1) Since the peel strength between the inter-groove region and the second transparent electrode layer 312B is 0.01 N or more, peeling can be suppressed in the portion of the light controlling sheet 310 that includes the inter-groove region.

(5-2) Because the peel strength per unit length between the narrowed portion 330A and the second transparent electrode layer 312B is 0.1 N/10 mm or greater, when the light-controlling sheet 310 has a narrowed portion 330A with a width of 2 mm or greater, peeling is suppressed in the portion including the narrowed portion 330A.

(5-3) It is possible to prevent peeling of the light controlling sheet 310 in the portion including the inter-groove region sandwiched between the groove bends 120GB.
(5-4) Peeling between the inter-groove region and the second transparent electrode layer 312B is suppressed in at least a part of the portion including the inter-groove region defined by the groove bend portion 120GB.

(5-5) The peel strength between the conductive region and the second transparent electrode layer 312B is 0.38 N/25 mm, so peeling between the conductive region and the second transparent electrode layer 312B is suppressed even in the groove regions, which are narrower than the conductive region.

(5-6) Even when the floating electrode element 331 is placed near the first connection region 324A, an increase in resistance is suppressed in the portion of the drive electrode element 330 located between the first connection region 324A and the floating electrode element 331. This prevents a decrease in the effective voltage applied to the portion of the drive electrode element 330 that is farther away from the first connection region 324A than the floating electrode element 331.

(5-7) Because the width of the narrowed portion 330A provided in the driving electrode element 330 is 1 mm or more, peeling of the first transparent electrode layer 312A or the first transparent support layer 313A is unlikely to occur during the groove 3120 formation process or after the groove 3120 is formed.

(5-8) Because the width of the narrowed portion 330A is 1 mm or more, poor conduction caused by increased resistance in the narrowed portion 330A is suppressed, thereby making it possible to appropriately control the diffuse transmittance of the first drive region 320A and the second drive region 320B. Therefore, patterns can be clearly displayed on the light-adjusting sheet 310, thereby enhancing the design of the light-adjusting sheet 310.

(5-9) The first driving region 320A and the second driving region 320B surrounded by the non-driving region 321 are electrically connected by the conductive portion 326 including the narrowed portion 330A. Therefore, the changes in the diffuse transmittance of the driving regions 320A and 320B can be synchronized depending on the state of the voltage signal applied to the driving electrode element 330.

(5-10) The angle of the bent portion 3102 in the non-driving region 321 or the angle between the tangents 3105, 3106 of the bent portion 3102 is 10 degrees or greater. Therefore, peeling of the first transparent electrode layer 312A or the first transparent support layer 313A is less likely to occur during the groove 3120 formation process, making it easier to form the driving electrode element 330 and the floating electrode element 331 into the desired shape. This allows patterns to be clearly displayed on the light control sheet 310.

(5-11) The grooves 3120 that separate the driving region 320 and the non-driving region 321 penetrate the first transparent electrode layer 312A, but have a depth that does not penetrate the first transparent electrode layer 312A. Therefore, light scattering by the grooves 3120 is suppressed on the surface of the first transparent support layer 313A opposite the support surface 3130. As a result, the grooves 3120 can be made less noticeable when the light controlling sheet 310 is viewed from the first transparent electrode layer 312A side, at least from a position facing the surface opposite the support surface 3130. This improves the aesthetic appearance of the light controlling sheet 310.

Sixth Embodiment
A sixth embodiment of the light controlling sheet will be described with reference to Figure 48. Note that in the sixth embodiment, the layered structure of the light controlling sheet 310 differs from that of the light controlling sheet 310 of the fifth embodiment. Hereinafter, the same parts as in the fifth embodiment will be given the same reference numerals, and detailed description thereof will be omitted. Note that, like the light controlling sheet 310 of the fifth embodiment, the light controlling sheet of the sixth embodiment can also be provided with the antiviral film provided in the light controlling sheet of the first embodiment, and the antiviral film or antiviral layer described in the modified example of the first embodiment.

FIG. 48 shows the cross-sectional structure of the light controlling sheet 310.
As shown in Figure 48, the driving electrode elements 330 and floating electrode elements 331 included in the first transparent electrode layer 312A are separated by grooves 3120. The grooves 3120 extend along the thickness direction of the first transparent electrode layer 312A. In this embodiment, the grooves 3120 penetrate the first transparent electrode layer 312A and the first transparent support layer 313A. The grooves 3120 have openings 3122 located on the surface of the first transparent electrode layer 312A that contacts the light control layer 311, and openings 3124 located on the surface of the first transparent support layer 313A opposite to the surface that contacts the first transparent electrode layer 312A. The driving electrode elements 330 and the floating electrode elements 331 are insulated from each other by being separated by the grooves 3120.

The light-adjusting sheet 310 further includes an adhesive layer 345 and a protective layer 344. A portion of the adhesive layer 345 fills the groove 3120. The adhesive layer 345 can bond the protective layer 344 and the first transparent support layer 313A and may be formed from a translucent material. For example, the adhesive layer 345 is an optically clear adhesive film that bonds the first transparent support layer 313A and the protective layer 344. If the light-adjusting sheet 310 includes an antiviral film, the antiviral film may be provided instead of the adhesive layer 345 and the protective layer 344. Alternatively, the light-adjusting sheet 310 may include an antiviral film positioned on the protective layer 344. In this case, the adhesive layer of the antiviral film contacts the protective layer 344.

In the light-controlling sheet 310 of this embodiment, as in the light-controlling sheet 310 of the fifth embodiment, the peel strength between the narrowing portion 330A and the second transparent electrode layer 312B may be 0.01 N or more. Furthermore, when the width of the narrowing portion 330A is 2 mm or more, the peel strength between the narrowing portion 330A and the second transparent electrode layer 312B per unit length in the width direction of the narrowing portion 330A may be 0.1 N/10 mm. Furthermore, the peel strength between the inter-groove region of the groove bend portion 120GB and the second transparent electrode layer 312B may be 0.01 N or more. Furthermore, the inter-groove region may include a portion where the width of the inter-groove region is 2 mm or more. In this portion, the peel strength between the inter-groove region and the second transparent electrode layer 312B per unit length in the width direction of the inter-groove region may be 0.1 N/10 mm.

[Method of manufacturing light controlling sheet]
An example of a method for manufacturing the light controlling sheet 310 will be described.
As in the fifth embodiment, a first film 351A including a first transparent electrode layer 312A and a first transparent support layer 313A and a second film 351B including a second transparent electrode layer 312B and a second transparent support layer 313B are prepared. Furthermore, spacers 315 are dispersed on each of the films 351A and 351B, and then a light-controlling material containing a polymerizable composition and a liquid crystal composition is applied. After forming light-controlling layers 311A and 311B from the light-controlling material, the pair of films 351A and 351B are laminated together, and the second film 351B is bonded to the first film 351A while applying a predetermined amount of pressure to the pair of films 351A and 351B.

In the laminate thus formed, an incision is made from the surface 3131 (see Figure 48) opposite the support surface 3130 of the first transparent support layer 313A down to the light-control layer 311. This forms a groove 3120 that penetrates the first transparent support layer 313A and the first transparent electrode layer 312A. Note that the groove 3120 can be formed using a method similar to that of the first embodiment. Thereafter, an adhesive layer 345 and a protective layer 344 are layered on the surface 3131 of the first transparent support layer 313A.

In this way, if grooves 3120 are formed in the light-adjusting sheet 310 after forming the light-adjusting sheet 310 including the first transparent electrode layer 312A, the second transparent electrode layer 312B, the light-adjusting layer 311, and the first transparent support layer 313A, the light-adjusting sheet 310 may satisfy the following. That is, the light-adjusting sheet 310 may be a light-adjusting sheet for forming inter-groove regions having a width of 2 mm or more, and the peel strength of the light-adjusting sheet 310 may be 0.38 N/25 mm or more. The inter-groove regions may be narrowed portions 330A, as described above, or may be regions surrounded by groove bends 120GB.

In this case, even if the first transparent electrode layer 312A of the light controlling sheet 310 is patterned to have inter-groove regions, peeling is prevented from occurring in the portion of the light controlling sheet 310 that includes the inter-groove regions. This makes it possible to prevent poor conductivity caused by peeling, thereby improving the design of the light controlling sheet 310.

The grooves 3120 do not have to be formed after forming the laminate in which the light-controlling layer 311 is sandwiched between the films 351A and 351B. For example, the grooves 3120 may be formed between any of the following steps in the process of forming the laminate. That is, the grooves 3120 may be formed before the step of spraying the spacers 315 on the first film 351A, between the step of spraying the spacers 315 and the step of applying the light-controlling material, between the step of forming the light-controlling layer 311A and the step of laminating the films 351A and 351B, etc.

According to the sixth embodiment, in addition to the effects (5-1) to (5-10) described above, the following effects can be obtained.
(6-1) Even if the first transparent electrode layer 312A of the light-controlling sheet 310 is patterned to have an inter-groove region, peeling is prevented from occurring in the portion of the light-controlling sheet 310 that includes the inter-groove region.

(6-2) Because the grooves 3120 have a depth that penetrates the first transparent support layer 313A and the first transparent electrode layer 312A, it is possible to form the grooves 3120 after laminating the first transparent support layer 313A, the first transparent electrode layer 312A, the light control layer 311, the second transparent electrode layer 312B, and the second transparent support layer 313B. It is also possible to form the grooves 3120 between the processes for forming each layer. This allows for greater flexibility in the manufacturing process of the light control sheet 310.

[Modifications of the Fifth and Sixth Embodiments]
The above-described embodiments can be modified as follows: The following modifications may be combined and implemented.

[Number of non-driven areas]
- In each embodiment, the second driving region 320B surrounded by a non-driving region 321 having a single line shape and the first driving region 320A located outside the non-driving region 321 are connected by a conductive portion 326 including a narrowing portion 330A, but the number of non-driving regions 321 provided in the light control sheet 310 is not limited to one.

FIG. 49 shows an example of a light controlling sheet 310 provided with a plurality of non-drive areas 321 .
As shown in Fig. 49 , the non-driven region 321 includes a floating region 322 and a boundary region 323. The boundary region 323 has a frame shape. The boundary region 323 defines the floating region 322, which is a closed region. In the example shown in Fig. 49 , the boundary region 323 included in the light controlling sheet 310 surrounds the floating region 322, which has a star shape. In other words, the floating region 322 is defined by the boundary region 323, which has a hollow star shape.

The light-controlling sheet 310 has two distinct, independent non-drive regions 321. Between the two non-drive regions 321 is a narrowed portion 330A sandwiched between two distinct grooves 3120. The narrowed portion 330A is a portion of the first transparent electrode layer 312A whose width is narrowed by the proximity of two distinct grooves 3120. In the light-controlling sheet 310, the portion including the narrowed portion 330A is a conductive portion 327, which provides electrical conductivity to the drive regions 320 located around the conductive portion 327.

The width L3 of the narrowed portion 330A may be 1 mm or more. In other words, the distance between two different non-driven regions 321 may be 1 mm or more. By making the width L3 of the narrowed portion 330A 1 mm or more, a decrease in conductivity in the narrowed portion 330A is suppressed, which makes it easier to equalize the diffuse transmittance in the driven regions 320 connected via the narrowed portion 330A. Note that although the light controlling sheet 310 shown in Figure 49 has two non-driven regions 321, the light controlling sheet 310 may have three or more non-driven regions 321.

In each embodiment, the groove 3120 has a closed frame shape surrounding the floating electrode element 331. Alternatively, the groove 3120 does not have to have a closed frame shape surrounding the floating electrode element 331 as long as it extends along the support surface 3130 of the first transparent support layer 313A and satisfies the following. For example, the groove 3120 may extend from a starting point located at a first end of one of the four sides of the rectangular light-controlling sheet 310, through the periphery of the floating region 322, and to an ending point located at a second end. The second end may be located on the same side as the first end of the four sides of the light-controlling sheet 310, or on a different side. Furthermore, even if the light-controlling sheet 310 is not rectangular, it is sufficient that the starting and ending points of the groove 3120 are located at the ends of the light-controlling sheet 310 and that the groove 3120 passes through the periphery of the floating region 322 during its extension.

[Light control sheet type]
The light controlling sheet 310 may be of a reverse type. In the reverse type light controlling sheet 310, when no voltage signal is applied between the transparent electrode layers 312A and 312B, the incident light is transmitted, thereby reducing the diffuse transmittance, and when a voltage signal is applied, the incident light is scattered, thereby increasing the diffuse transmittance.

FIG. 50 shows an example of a reverse-type light controlling sheet 310.
50 , the reverse-type light-controlling sheet 310 includes a functional layer 3111 including a transparent polymer layer and a liquid crystal composition, a first alignment layer 3112, and a second alignment layer 3113. The functional layer 3111, the first alignment layer 3112, and the second alignment layer 3113 constitute the light-controlling layer 311. The first alignment layer 3112 is located between the functional layer 3111 and the first transparent electrode layer 312A and is in contact with these layers. The second alignment layer 3113 is located between the functional layer 3111 and the second transparent electrode layer 312B and is in contact with these layers.

Each of the first alignment layer 3112 and the second alignment layer 3113 is, for example, a vertical alignment film. The vertical alignment film aligns the long axis direction of the liquid crystal molecules along the thickness direction of the light control layer 311. In this way, the first alignment layer 3112 and the second alignment layer 3113 regulate the orientation of the multiple liquid crystal molecules contained in the light control layer 311. The material for forming each of the first alignment layer 3112 and the second alignment layer 3113 may be any of the materials listed in the first embodiment.

The grooves 3120 have openings 3122 on the surface of the first alignment layer 3112 that contacts the light-controlling layer 311, and penetrate the first alignment layer 3112 and the first transparent electrode layer 312A, but do not penetrate the first transparent support layer 313A. In other words, the depth of the grooves 3120 is smaller than the sum of the thicknesses of the first alignment layer 3112, the first transparent electrode layer 312A, and the first transparent support layer 313A. A portion of the light-controlling layer 311 is filled into the grooves 3120. The grooves 3120 may also penetrate the first transparent support layer 313A, similar to the grooves 3120 provided in the light-controlling sheet 310 of the sixth embodiment.

When the light-controlling sheet 310 includes the first alignment layer 3112 and the second alignment layer 3113, in the driving region 320, when no voltage signal is applied to the first transparent electrode layer 312A and the second transparent electrode layer 312B, the long axis direction of the liquid crystal molecules is aligned with the thickness direction of the light-controlling layer 311. Therefore, the driving region 320 is transparent. On the other hand, when a voltage signal is applied to the first transparent electrode layer 312A and the second transparent electrode layer 312B in the driving region 320, the long axis direction of the liquid crystal molecules intersects with the thickness direction of the light-controlling layer 311. Therefore, the driving region 320 appears cloudy, in other words, opaque. When the light-controlling sheet 310 includes the first alignment layer 3112 and the second alignment layer 3113, in the floating region 322 and the boundary region 323, the long axis direction of the liquid crystal molecules is always aligned with the thickness direction of the light-controlling layer 311, so the non-driving region 321 is always transparent.

Therefore, when the light-adjusting sheet 310 is not driven, all of the driving areas 320 are transparent, and images such as letters and patterns made up of the non-driving areas 321 are not visible. On the other hand, when the light-adjusting sheet 310 is driven, the driving areas 320 become opaque, while the non-driving areas 321 are transparent, so images such as letters and patterns made up of the non-driving areas 321 become visible.

In this way, even when the light-controlling sheet 310 includes the first alignment layer 3112 and the second alignment layer 3113, regions with different diffuse transmittances are formed within the surface of the light-controlling sheet 310, and the difference in diffuse transmittance between these regions only appears when the light-controlling sheet 310 is in operation. This makes it possible to improve the design of the light-controlling sheet 310.

In addition, in the example shown in Figure 50, the grooves 3120 penetrate the first alignment layer 3112, but the first alignment layer 3112 may be formed after the grooves 3120 are formed in a laminate consisting of the first transparent electrode layer 312A and the first transparent support layer 313A. In this case, the first alignment layer 3112 is formed so as to follow the bottom and side surfaces of the grooves 3120. Even in this case, the grooves 3120 can be made less noticeable when the light-adjusting sheet 310 is viewed from a viewpoint opposite the first surface 311F or second surface 311R of the light-adjusting sheet.

[Groove position]
As shown in FIG. 49 , when the light-adjusting sheet 310 has multiple grooves 3120, the grooves 3120 may be located at the same depth in the stacking direction of the layers constituting the light-adjusting sheet 310, i.e., in the thickness direction of the light-adjusting sheet 310. Alternatively, the multiple grooves 3120 may be located at different depths in the stacking direction. Examples are listed in FIGS. 51 to 53 , and in each of these examples, the grooves 3120 can be formed using the methods described in the above-mentioned embodiments. Furthermore, while the following describes a normal-type light-adjusting sheet 310, the following examples may also be applied to a reverse-type light-adjusting sheet 310. Furthermore, in the examples shown in FIGS. 51 to 53 , the grooves 3120 are not filled with a light-adjusting material, but at least a portion of the grooves 3120 may be filled with a light-adjusting material.

As shown in FIG. 51, the first groove 3120A penetrates the first transparent support layer 313A and the first transparent electrode layer 312A. In contrast, the second groove 3120B penetrates only the second transparent electrode layer 312B. The second groove 3120B may be formed in the second transparent electrode layer 312B via the second transparent support layer 313B. In this case, the second groove 3120B may be formed using, for example, a laser cutting device.

As shown in Figure 52, the multiple grooves 3120 are formed by cutting from the first transparent support layer 313A through at least the first transparent support layer 313A and the first transparent electrode layer 312A. The first grooves 3120A penetrate the first transparent support layer 313A and the first transparent electrode layer 312A. The second grooves 3120B penetrate the first transparent support layer 313A and the first transparent electrode layer 312A as well as the light-control layer 311 and the second transparent electrode layer 312B.

As shown in Figure 53, the first groove 3120A penetrates the first transparent support layer 313A and the first transparent electrode layer 312A. The second groove 3120B penetrates the second transparent support layer 313B and the second transparent electrode layer 312B.

- In each of the examples shown in Figures 51 to 53, the second groove 3120B does not overlap the first groove 3120A in a plan view facing the first surface 311F of the light controlling sheet 310. The area where each groove 3120A, 3120B is located is the boundary area 323. Furthermore, if the first groove 3120A and the second groove 3120B are formed close to each other at the same position in the stacking direction of the light controlling sheet 310, the strength of the area sandwiched between the grooves 3120A, 3120B and its surrounding areas is likely to decrease. In this regard, as described above, by forming the grooves 3120A, 3120B at different positions in the stacking direction, it is possible to prevent a decrease in the strength of the light controlling sheet 310 even if the grooves 3120A, 3120B are formed close to each other.

[Floating electrode element]
In each embodiment, a voltage signal is applied to the driving electrode element 330, which is the first electrode element, and no voltage signal is applied to the floating electrode element 331, which is the second electrode element. Alternatively, voltage signals may be applied separately to the first electrode element and the second electrode element. In this case, wiring for applying a voltage signal to the second electrode element is connected to the end of the second electrode element. The terminal connected to the first electrode element and the terminal connected to the second electrode element are separate terminals for each voltage signal.

As described above, when the second electrode elements are located at the edge of the light-controlling sheet 310, it is easy to connect wiring to the second electrode elements. For example, the first region where the first electrode elements are located can be switched between transparent and opaque by switching the state of a voltage signal applied to the first electrode elements. The second region where the second electrode elements are located can be switched between transparent and opaque, independently of the first region, by switching the state of a voltage signal applied to the second electrode elements.

In this case, the state of the light-adjusting sheet 310 can be switched between the following four states: a first state in which both the first and second regions are opaque; a second state in which the first region is opaque and the second region is transparent; a third state in which the first region is transparent and the second region is opaque; and a fourth state in which both the first and second regions are opaque. This allows for a more diverse range of changes in the decorative state of a space using the light-adjusting sheet 310, further improving the design of the light-adjusting sheet 310.

The diffuse transmittance in at least one of the first and second regions may be controlled to a diffuse transmittance that corresponds between transparency and opacity. In a light-controlling sheet 310 having a light-controlling layer 311 containing a liquid crystal composition, when the potential difference between the first transparent electrode layer 312A and the second transparent electrode layer 312B is within a predetermined range, the diffuse transmittance of the light-controlling sheet 310 gradually changes as the potential difference changes. Therefore, by controlling the potential difference between the first transparent electrode layer 312A and the second transparent electrode layer 312B in the first or second region to a value between the potential difference at which each region becomes transparent and the potential difference at which each region becomes opaque, each region can be controlled to be translucent, that is, have a diffuse transmittance that is between transparency and opaque.

Specifically, for example, the first region can be switched between transparent and opaque by switching the state of application of a voltage signal to the first electrode element, while the second region can be switched between translucent and opaque by switching the state of application of a voltage signal to the second electrode element. Also, for example, when the first region is transparent, the second region is controlled to be translucent. This makes it possible to switch between a state in which both the first and second regions are opaque and a state in which the first region is opaque and the second region is translucent. This also makes it possible to improve the design of the light-controlling sheet 310.

[Number of stenoses]
In the fifth embodiment, the drive regions 320A and 320B defined by the non-drive region 321 are electrically connected to each other via one narrowing portion 330A. Alternatively, the drive regions 320A and 320B defined by the non-drive region 321 may be electrically connected to each other via multiple narrowing portions 330A. In other words, the light controlling sheet 310 may include multiple conductive portions 326 sandwiched between the non-drive regions 321. Each narrowing portion 330A has a configuration similar to that of the narrowing portion 330A in the fifth embodiment. For example, as shown in FIG. 54 , the drive regions 320A and 320B may be electrically connected to each other via two narrowing portions 330A. The width of each narrowing portion 330A may be, for example, 1 mm or more. In this case, the light controlling sheet 310 has two non-driving regions 321, and each non-driving region 321 has a first end 321A and a second end 321B. In the example shown in Figure 54, one narrowed portion 330A is located between the second end 321B of the first non-driving region 321 and the first end 321A of the second non-driving region 321.

[Width of the constricted part]
The width L1 of the narrowing portion 330A may be less than 1 mm. Even in this case, by increasing the voltage applied between the transparent electrode layers 312A and 312B compared to when the width L1 of the narrowing portion 330A is 1 mm or greater, it is possible to reduce the difference in diffuse transmittance between the first driving region 320A and the second driving region 320B connected by the conductive portion 326 including the narrowing portion 330A. Alternatively, by reducing the area of the second driving region 320B connected to the conductive portion 326 including the narrowing portion 330A compared to when the width of the narrowing portion 330A is 1 mm or greater, it is possible to reduce the difference in diffuse transmittance between the first driving region 320A and the second driving region 320B.

[Non-driven area]
The light controlling sheet 310 may include the first electrode element and the groove 3120C, but may not include the second electrode element. The groove 3120C has a width wide enough that an observer can recognize the shape of the groove 3120C when viewing the light controlling sheet 310 from a viewpoint opposite the first surface 311F of the light controlling sheet 310. In the example shown in Figure 55, the light controlling sheet 310 includes the first electrode element and the groove 3120C, but does not include the second electrode element insulated from the first electrode element by the groove 3120C. The portion of the light controlling sheet 310 that includes the first electrode element changes its diffuse transmittance depending on the state of application of a voltage signal. The groove 3120C may be a recess that does not penetrate the light controlling sheet 310.

In the example shown in Figure 55, the groove 3120C has a C-shape. In the light control sheet 310, the area where the groove 3120C is formed does not include an electrode element. The groove 3120C is filled with at least one of a transparent polymer layer and a liquid crystal composition. Alternatively, the groove 3120C may be filled with a substance other than the transparent polymer layer and the liquid crystal composition, or the groove 3120C may be a void, which is an area not filled with a substance.

When the grooves 3120C are filled with at least one of a liquid crystal composition and a transparent polymer layer, the grooves 3120C have scattering properties. In this case, when the light-adjusting sheet 310 is not driven, the driving regions 320 where the grooves 3120C are not formed and the grooves 3120C are both opaque. On the other hand, when the light-adjusting sheet 310 is driven, the driving regions 320 are transparent, while the grooves 3120C remain opaque. Therefore, only the grooves 3120C appear whitish, for example, or in other words, cloudy, which makes it possible to see the image of the pattern, such as letters or pictures, formed by the grooves 3120C. In the example shown in Figure 55, the letter "C" is visible.

In contrast, if the grooves 3120C are filled with a substance other than the transparent polymer and liquid crystal composition that has lower scattering properties than the liquid crystal composition and transparent polymer layer, or if the grooves 3120C are voids, the grooves 3120 will be transparent. In this case, when the light-adjusting sheet 310 is driven, the driving regions 320 where the grooves 3120C are not formed and the grooves 3120C are both transparent. On the other hand, when the light-adjusting sheet 310 is not driven, the driving regions 320 are opaque, while the grooves 3120C remain transparent. Therefore, images of characters, patterns, and other graphics formed by the grooves 3120C are visible.

Furthermore, when the light controlling sheet 310 has multiple grooves 3120C, the width L30 of the narrowed portion 330A defined by the multiple grooves 3120C may be 1 mm or more. Furthermore, the width L10 of the narrowed portion 330A formed by one groove 3120C may be 1 mm or more. Of the first transparent electrode layer 312A, the area surrounded by the grooves 3120C is the second drive electrode element, and the area located outside the grooves 3120C and connected to the second drive electrode element is the first drive electrode element.

[Test Example]
A test example will be described with reference to FIGS. 56 to 60.
[Resistance value]
[Test Example 2-1]
As shown in FIG. 56 , a rectangular resistance measurement area 3143 was formed on a substrate having a transparent electrode layer 3140 and a transparent support layer 3141. The resistance measurement area 3143 was 50 mm × 25 mm in size. Furthermore, two resistance measurement areas 3143 were connected via a narrowed portion 3144 (conductive portion) having a width L4 of 50 mm and a length L5 of 100 mm, thereby preparing a measurement sample. The measurement sample was prepared so that the long sides of each resistance measurement area 3143 were connected by the narrowed portion 3144. Furthermore, a tester was connected to the two resistance measurement areas 3143 to measure the resistance.

[Test Example 2-2]
A measurement sample for Test Example 2-2 was prepared in the same manner as in Test Example 2-1, except that the width L4 of the narrowed portion 3144 in Test Example 2-1 was set to 20 mm.

[Test Example 2-3]
A measurement sample for Test Example 2-3 was prepared in the same manner as in Test Example 2-1, except that the width L4 of the narrowed portion 3144 in Test Example 2-1 was set to 10 mm.

[Test Example 2-4]
A measurement sample for Test Example 2-4 was prepared in the same manner as in Test Example 2-1, except that the width L4 of the narrowed portion 3144 in Test Example 2-1 was set to 5 mm.

[Test Example 2-5]
A measurement sample for Test Example 2-5 was prepared in the same manner as in Test Example 2-1, except that the width L4 of the narrowed portion 3144 in Test Example 2-1 was set to 2 mm.

[Test Example 2-6]
A measurement sample for Test Example 2-6 was prepared in the same manner as in Test Example 2-1, except that the width L4 of the narrowed portion 3144 in Test Example 2-1 was set to 1 mm.

[Test Example 2-7]
A measurement sample for Test Example 2-7 was prepared in the same manner as in Test Example 2-1, except that the width L4 of the narrowed portion 3144 in Test Example 2-1 was set to 0.5 mm.

[Measurement method and evaluation results]
The resistance value of each measurement sample was measured using a digital multimeter (TY530, manufactured by Yokogawa Measurement Corporation).

As shown in Figure 57, the resistance values (Ω) of the measurement samples of Test Examples 2-1 to 2-6 were 494Ω, 719Ω, 1,225Ω, 2,259Ω, 5,220Ω, and 10,900Ω, respectively, and were found to increase as the width L4 of the narrowed portion 3144 became smaller. The resistance value of the measurement sample of Test Example 2-7 was 26,800Ω, which was found to be significantly higher than that of Tests 2-1 to 2-6.

[Effective voltage]
Next, the effective voltage was measured in a light-control sheet in which a light-control layer was sandwiched between a pair of substrates.
[Test Example 2-8]
A light-controlling sheet having a layered structure similar to that of the light-controlling sheet 310 shown in Figure 41 was prepared. Two rectangular characteristic measurement areas measuring 50 mm x 25 mm were secured at separate locations, and these characteristic measurement areas were connected by a conductive portion including a constriction. The widths of the conductive portion and the constriction were set to 50 mm, and the length of the constriction was set to 100 mm.

Furthermore, two connection areas were formed in each characteristic measurement area using a method similar to the method for forming connection areas in the light control sheet 310 shown in Figure 41. That is, for each characteristic measurement area, a notch was made in the corner of one of the surfaces (the second surface), the transparent support layer and transparent electrode layer were peeled off, and the liquid crystal was then removed to form a connection area. Similarly, a notch was made in the corner of the other surface (the first surface), the transparent support layer and transparent electrode layer were peeled off, and the liquid crystal was then removed to form a connection area. External wiring was then connected to these connection areas. This made it possible to control the voltage applied to one characteristic measurement area and to connect an effective voltage measuring device to the other characteristic measurement area.

[Test Example 2-9]
A measurement sample was prepared in the same manner as in Test Example 1-8, except that the width of the narrowed portion was set to 20 mm.
[Test Example 2-10]
A measurement sample was prepared in the same manner as in Test Example 1-8, except that the width of the narrowed portion was set to 10 mm.

[Test Example 2-11]
A measurement sample was prepared in the same manner as in Test Example 1-8, except that the width of the narrowed portion was set to 5 mm.
[Test Example 2-12]
A measurement sample was prepared in the same manner as in Test Example 1-8, except that the width of the narrowed portion was set to 2 mm.

[Test Example 2-13]
A measurement sample was prepared in the same manner as in Test Example 1-8, except that the width of the narrowed portion was set to 1 mm.
[Test Example 2-14]
A measurement sample was prepared in the same manner as in Test Example 1-8, except that the width of the narrowed portion was set to 0.5 mm.

[Measurement method and evaluation results]
A power supply (LP1-RS232, manufactured by Toppan Printing Co., Ltd.) was connected to one of the characteristic measurement areas. A voltage of 80 V with a frequency of 40 Hz and a rectangular waveform was applied using the power supply. The above-mentioned digital multimeter was connected to the other characteristic measurement area, and the effective voltage was measured using the digital multimeter.

As shown in Figure 58, in Test Examples 2-8 to 2-13, where the width of the conductive portion was 1.0 mm or more, the effective voltage was found to be between 79.7 V and 81.4 V. In Test Examples 2-8 to 2-13, the effective voltage decreased as the width of the constricted portion included in the conductive portion narrowed, but there was no significant change in the effective voltage. In contrast, in Test Example 2-14, where the width of the constricted portion included in the conductive portion was 0.5 mm, the effective voltage was found to be 7.9 V. In other words, it was found that the effective voltage dropped significantly when the width of the constricted portion was less than 1 mm. Furthermore, in Test Example 2-14, it was found that repeated starting and stopping of voltage application caused poor conductivity.

[Peel strength]
[Test Example 3-1]
A first transparent film and a second transparent film were prepared, each including a transparent electrode layer made of indium tin oxide and a transparent support layer supporting the transparent electrode layer, the transparent support layer being formed from polyethylene terephthalate. Next, a coating liquid containing an acrylic monomer and liquid crystal was prepared. The first transparent film and the second transparent film were placed opposite each other so that the transparent support layer was positioned on the outside of the transparent electrode layer, and the coating liquid was sandwiched between the first transparent film and the second transparent film. Then, ultraviolet light was irradiated onto the coating liquid through the first transparent film and the second transparent film, causing phase separation between the liquid crystal and the transparent resin layer, thereby forming a light-controlling layer. This resulted in the light-controlling sheet of Test Example 3-1.

[Test Example 3-2]
A light-controlling sheet of Test Example 3-2 was obtained in the same manner as in Test Example 3-1, except that the ratio of the mass of the monomer to the mass of the liquid crystal in the coating liquid was made smaller.

[Test Example 3-3]
A light-controlling sheet of Test Example 3-3 was obtained in the same manner as in Test Example 3-2, except that the ratio of the mass of the monomer to the mass of the liquid crystal in the coating liquid was made smaller.

[Test Example 3-4]
In Test Example 3-1, the acrylic monomer contained in the coating liquid was changed to an acrylic monomer having lower adhesion to each transparent film, and the light-controlling sheet of Test Example 3-4 was obtained in the same manner as in Test Example 3-1.

[Test Example 3-5]
A light-controlling sheet of Test Example 3-5 was obtained in the same manner as in Test Example 3-3, except that the ratio of the mass of the monomer to the mass of the liquid crystal in the coating liquid was made smaller.

[Test Example 3-6]
A light-controlling sheet of Test Example 3-6 was obtained in the same manner as in Test Example 3-1, except that the time for irradiating the coating liquid with ultraviolet light was shortened.

[Test Example 3-7]
In Test Example 3-5, the acrylic monomer contained in the coating liquid was changed to an acrylic monomer with lower adhesion to each transparent film, and the light-controlling sheet of Test Example 3-7 was obtained in the same manner as Test Example 3-5.

[Test Example 3-8]
A light-controlling sheet of Test Example 3-8 was obtained in the same manner as in Test Example 3-6, except that the time for irradiating the coating liquid with ultraviolet light was shortened.

[Measurement method and evaluation results]
From each test example, a first test piece having a width of 2 mm, a test piece having a width of 5 mm, a test piece having a width of 10 mm, a test piece having a width of 15 mm, a test piece having a width of 20 mm, and a test piece having a width of 25 mm were cut out. The peel strength of each test example was measured using a method conforming to 6.9.3 a) 180-degree peel test of JIS A 5759:2016 "Films for Architectural Window Glass." The evaluation results of the peel strength are shown in Figure 59. A small desktop testing machine (Shimadzu Corporation, EZ-LX) was used to measure the peel strength.

After preparing the light-controlling sheet using the same method as in each test example, a cutting plotter was used to create a groove penetrating the transparent electrode layer of the first transparent film from the side opposite the side facing the light-controlling layer. This resulted in the formation of one narrowed portion with the following widths: a narrowed portion with a width of 2 mm, a narrowed portion with a width of 5 mm, a narrowed portion with a width of 10 mm, a narrowed portion with a width of 15 mm, a narrowed portion with a width of 20 mm, and a narrowed portion with a width of 25 mm in the transparent electrode layer of the first transparent film. This resulted in the formation of one first driving region adjacent to the connection region, a conductive portion including a narrowed portion, and one second driving region for each conductive portion in the light-controlling sheet. Note that the second driving region was connected to the first driving region through the conductive portion to which the second driving region was connected, but was not electrically connected to other regions of the light-controlling sheet.

As shown in Figure 59, in each test example, the peel strength of the test specimen increased with increasing specimen width. In test example 3-1, the peel strength was found to be within the range of 0.022 N to 0.616 N, and in test example 3-2, the peel strength was found to be within the range of 0.025 N to 0.610 N. In test example 3-3, the peel strength was found to be within the range of 0.021 N to 0.530 N, and in test example 3-4, the peel strength was found to be within the range of 0.019 N to 0.469 N. In test example 3-5, the peel strength was found to be within the range of 0.014 N to 0.400 N, and in test example 3-6, the peel strength was found to be within the range of 0.015 N to 0.380 N. In test example 3-7, the peel strength was found to be within the range of 0.007 N or more and 0.200 N or less, and in test example 3-8, the peel strength was found to be within the range of 0.002 N or more and 0.060 N or less.

For each light-controlling sheet with a constricted portion formed, an evaluation was conducted to determine whether the diffuse transmittance of the second driving region would change by applying a voltage between the transparent electrode layer of the first transparent film and the transparent electrode layer of the second transparent film. For the light-controlling sheets of test examples 3-1 to 3-6, it was found that the diffuse transmittance changed in all second driving regions between the state where a voltage was applied between the transparent electrode layers and the state where it was not applied, regardless of the width of the constricted portion contained in the conductive portion connecting the first driving region to the second driving region.

In contrast, with the light-adjusting sheet of test example 3-7, it was observed that the diffuse transmittance changed in the second drive region when the width of the narrowed portion was in the range of 5 mm to 25 mm, but when the width of the narrowed portion was 2 mm, it was observed that the diffuse transmittance did not change in the second drive region. Furthermore, with the light-adjusting sheet of test example 3-8, it was observed that the diffuse transmittance changed in the second drive region when the width of the narrowed portion was in the range of 10 mm to 25 mm, but when the width of the narrowed portion was 5 mm or less, it was observed that the diffuse transmittance did not change in the second drive region.

When the cross-sectional structure of the conductive portion was confirmed in Test Example 3-7 and Test Example 3-8, peeling was found to have occurred in the conductive portion when the narrowed portion width was 2 mm in Test Example 3-7. Furthermore, peeling was found to have occurred in the conductive portion when the narrowed portion width was 2 mm and when the narrowed portion width was 5 mm in Test Example 3-8. Therefore, it can be said that the lack of change in the diffuse transmittance of the second driving region was caused by peeling in the portion including the narrowed portion. In other words, in the light-controlling sheet, by having a peel strength of 0.01 N or more between the narrowed portion included in the first transparent electrode layer and the second transparent electrode layer, peeling in the narrowed portion can be suppressed, thereby making it possible to suppress poor conductivity caused by peeling.

Furthermore, as is clear from the peel strength measurement results, if the peel strength of the light-controlling sheet is 0.380 N/mm or more, peeling of the narrowed portion will not occur even when a narrowed portion with a width of 2 mm is formed.

Figure 60 shows the relationship between the peel strength of a 10 mm wide test specimen in each test example and the peel strength of a 5 mm wide test specimen in that test example, and the relationship between the peel strength of a 10 mm wide test specimen in each test example and the peel strength of a 2 mm wide test specimen in that test example.

As shown in Figure 60 and as described above, it was found that, regardless of the width of the narrowed portion, peeling in the area including the narrowed portion can be suppressed by ensuring that the peel strength between the narrowed portion and the second transparent electrode layer is 0.01 N or greater. Furthermore, it was found that, if the peel strength per unit length of 10 mm is 0.100 N or greater, peeling in the narrowed portion can be suppressed even when a narrowed portion with a width of 2 mm is formed.

21... Light-controlling sheet 31... Light-controlling layer 34... First transparent electrode layer 35... Second transparent electrode layer 41... First antiviral film 41A... Base material layer 41B... Antiviral layer 41C... Adhesive layer 42... Second antiviral film

Claims (4)

a first transparent electrode layer;
A second transparent electrode layer;
a light-controlling layer located between the first transparent electrode layer and the second transparent electrode layer;
a first transparent support layer located on the opposite side of the first transparent electrode layer from the light control layer;
an antiviral layer located on the opposite side of the first transparent electrode layer with respect to the first transparent support layer, the antiviral layer including an antiviral agent ;
a covering layer located between the first transparent support layer and the antiviral layer,
the first transparent support layer includes a support surface that supports the first transparent electrode layer and a protected surface that is a surface opposite to the support surface,
the first transparent electrode layer includes a first electrode element and a second electrode element;
the first electrode element and the second electrode element are separate layered bodies arranged along the support surface, and are electrically insulated from each other by grooves extending in a direction along the support surface;
a thickness direction of the first transparent electrode layer is a depth direction of the groove, the groove penetrates the first transparent support layer and the first transparent electrode layer in the depth direction, and has an opening in the surface to be protected;
The opening is covered with the covering layer.
Dimming sheet. The liquid crystal display device further includes an alignment layer sandwiched between the first transparent electrode layer and the light-controlling layer, the alignment layer being configured to increase the haze of the light-controlling layer by applying a voltage to the first transparent electrode layer;
the light-controlling layer comprises a resin layer located between the first transparent electrode layer and the second transparent electrode layer and having voids dispersed therein, and a liquid crystal composition containing liquid crystal molecules and filling the voids;
a first high density portion in which the density of the liquid crystal composition per unit thickness is high;
a low-density portion in which the density of the liquid crystal composition per unit thickness is lower than that of the first high-density portion,
The light-controlling sheet according to claim 1 , wherein the first high-density portion is in contact with the first alignment layer. the groove is a first groove,
the first transparent electrode layer includes a third electrode element and a fourth electrode element;
the third electrode element and the fourth electrode element are separate layers aligned along the support surface and are electrically insulated from each other by a second groove extending along the support surface;
a depth direction of the second groove is a thickness direction of the first transparent electrode layer,
The light-controlling sheet according to claim 1 or 2, wherein the second grooves extend through the first transparent electrode layer to a position partway through the first transparent support layer in the thickness direction , and have a depth that does not penetrate the first transparent support layer. the groove is a first groove,
the first transparent electrode layer includes a third electrode element and a fourth electrode element;
the third electrode element and the fourth electrode element are separate layers aligned along the support surface and are electrically insulated from each other by a second groove extending along the support surface;
the third electrode element has a narrowed portion sandwiched by the second groove,
The light-controlling sheet according to claim 1 or 2, wherein the width of the narrowed portion is 1 mm or more and 30 mm or less .