JP5079445B2 - Liquid crystal device and electronic device - Google Patents

Description

  The present invention relates to a liquid crystal device and an electronic apparatus.

  Liquid crystal devices are widely used as display units for personal computers, mobile phones, and the like, but are known to require display light unlike self-luminous organic EL devices and the like. Display light includes illumination light and natural light outside the liquid crystal device, light source light inside the liquid crystal device, and the like. A liquid crystal device that uses external light is called a reflection type, and a light that uses internal light is a transmission type. being called. The reflective type is advantageous in that it consumes less power because it does not require a light source, and the transmissive type is advantageous in that it can display even in a dark place because it can secure light for display. In recent years, a transflective type in which a reflective type and a transmissive type are used together has been considered, and has attracted attention as a liquid crystal device having both advantages.

  The semi-reflective transmission type liquid crystal device includes a reflective display region that modulates external light incident from the display side with a liquid crystal layer and reflects the light to the display side, and a backlight provided on the opposite side of the display side of liquid crystal and the like. A transmissive display region that modulates the internal light by the liquid crystal layer and transmits the liquid crystal layer to the display side is provided. In general, the reflective display area is provided with a phase difference layer for adjusting the phase of light, so that a reduction in contrast due to a phase shift from the transmissive display area side can be prevented.

  Conventionally, as the retardation layer, an external retardation plate in which a retardation film having retardation is attached to the outer surface of the display side of the liquid crystal device has been employed. However, there are inconveniences such as that the retardation film is expensive and that the retardation film is thick, which obstructs the thinning of the liquid crystal device. In view of this, it has been considered that a liquid crystal device that is low-cost and can be thinned by a method of forming a retardation layer inside the liquid crystal device using a liquid crystal material (for example, Patent Document 1).

In Patent Document 1, after applying a liquid crystal material on the third alignment film and aligning it, the liquid crystal material is polymerized in the aligned state to obtain a predetermined retardation, and then patterned to obtain a reflective display region. Only the built-in retardation plate is formed. A first alignment film for aligning the liquid crystal layer is formed to cover the built-in retardation plate and the third alignment film. In this way, a liquid crystal device that is low in cost and can be thinned can be obtained. In addition, by forming the built-in retardation plate only in the reflective display area, it is said that the display quality can be prevented from being deteriorated due to unnecessary influence of light from the backlight in the transmissive display area from the built-in retardation plate. Yes.
JP 2005-338256 A

  However, in the method disclosed in Patent Document 1, the first alignment film that aligns the liquid crystal molecules of the liquid crystal layer may not be formed satisfactorily. That is, in Patent Document 1, a polyimide organic film is employed as the first alignment film as usual, and the polyimide organic film is generally formed by applying a liquid material and solidifying. The liquid material may have insufficient affinity with the base depending on the material difference from the base and the surface state of the base. If the affinity is insufficient, the base material repels the liquid material, and the repelled liquid material becomes round due to surface tension and becomes discrete in an island shape. Therefore, it becomes difficult to form a good first alignment film.

  In particular, at the step between the built-in retardation plate and the third alignment film, if the affinity between the liquid material and the substrate is insufficient, the step coverage of the liquid material is impaired, and the liquid material is disconnected. Is likely to occur. If step breakage occurs, discretization is promoted starting from this point, and it becomes more difficult to satisfactorily form the first alignment film.

  As described above, when formation failure occurs because the first alignment film is not formed satisfactorily, the liquid crystal is formed on the formation failure portion or on the peeling portion of the first alignment film generated from the formation failure portion. Insufficient molecular orientation occurs. If alignment defects of liquid crystal molecules occur, desired display cannot be performed, and the display quality of the liquid crystal device is impaired.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a liquid crystal device with good display quality. Another object is to provide a favorable electronic device including the liquid crystal device.

The liquid crystal device according to the present invention is a liquid crystal device having a reflective display region selectively provided in the display region , the first substrate, the second substrate facing the first substrate , the first substrate, and the second substrate . is sandwiched and the substrate, a liquid crystal layer containing liquid crystal molecules and, a first orientation film provided between the first substrate and the liquid crystal layer, the first alignment film and the liquid crystal layer of the reflection display area provided between the retardation layer granted refractive index anisotropy by the first alignment film provided over the first alignment film and the phase difference layer, the liquid crystal molecules of the liquid crystal layer given and a second alignment layer to align the direction, a second alignment film, the liquid material is formed is solidified, also less in the region where phase difference layer is provided position of retardation layers be between the retardation layer and the second alignment film in the peripheral portion, so only selectively on a portion of the retardation layer, the first intermediate layer having an affinity for the liquid material Provided, between the first alignment film and the second alignment film in the peripheral portion of the least even phase difference layer in the region where the phase difference layer is not provided, it has an affinity for the liquid material A second intermediate layer is provided.

Usually, the second alignment film is formed by applying a liquid material so as to cover the retardation layer and the first alignment film and then solidifying the liquid material. Here, when the phase difference layer and the first alignment layer is lyophobic to the material of the liquid, at the step portion of the retardation layer and the first alignment film, the step coverage of the liquid-like material It can be damaged and cause breakage of the liquid material. When the breakage of the liquid material occurs, the liquid material is rounded and discretized by the surface tension.
In the present invention, the step portion of the retardation layer and the first alignment layer, i.e. the peripheral portion of the peripheral edge and the retardation layer of the retardation layer, the first intermediate layer has an affinity to the liquid-like material and the second since the intermediate layer is provided, the step coverage of the liquid-like material that put the step portion is improved. Therefore, the breakage of the liquid material at the step portion is suppressed and the discretization of the liquid material is reduced, so that the liquid material is satisfactorily applied .

  In addition, even when a break occurs, an adsorption force that keeps the liquid material in the first intermediate layer acts due to the affinity, and this cancels the force that separates the liquid material from the peripheral portion of the retardation layer due to the surface tension. Therefore, the liquid material on the retardation layer is prevented from being discretized into islands. Similarly, the liquid material on the first alignment film is also prevented from being discretized into an island shape.

  As described above, since the liquid material is prevented from being discretized, the liquid material can be applied satisfactorily, and a good second alignment film can be obtained. Therefore, by using a good second alignment film, the liquid crystal molecules of the liquid crystal layer can be aligned in a predetermined direction, and this can be controlled in a desired direction. Therefore, desired display can be performed, and a liquid crystal device with high display quality can be obtained.

In addition , in- plane stress acts on the first intermediate layer and the retardation layer due to the difference in materials, the thermal effect during formation, and the like. This in-plane stress is considered to increase as the contact area between the first intermediate layer and the retardation layer increases. If the in-plane stress increases to some extent, the first substrate may be distorted due to the in-plane stress, which may cause inconveniences such as processing accuracy being lost in the manufacturing process. In extreme cases, the first substrate may be cracked, resulting in inconveniences such as loss of the yield of the liquid crystal device. In addition, the phase difference layer is distorted and cannot be functioned correctly. For example, there may be a disadvantage that display quality deteriorates.
By providing only selectively a first intermediate layer on a part of the phase difference layer, the than the case of providing, the first intermediate layer and the retardation layer across between the retardation layer and the second alignment layer In-plane stress is reduced. Therefore, inconvenience when the in-plane stress is large as described above can be avoided, and a good liquid crystal device can be obtained.

The first intermediate layer preferably has a first transparent portion made of a translucent material, the first transparent portion is preferably made of ITO or SnO _2.
In this way, since the light can be transmitted through the first light transmitting portion, the first light transmitting portion can be used as a display region, and the display region is prevented from becoming narrow.
In a liquid crystal device, ITO or SnO ₂ is very common as an electrode material. Further, since the alignment film is generally provided on the electrode, the alignment film material is designed to have a high affinity for the electrode. Therefore, if the first light transmitting portion made of ITO or SnO _2, will have a sufficient affinity for the second alignment film first light transmitting portion made of a normal alignment film material. Therefore, the material and method for forming the second alignment film can be used, and a highly reliable liquid crystal device can be obtained.

The first intermediate layer has a portion which is provided on the periphery of the phase difference layer may be configured to have a first light-shielding portion made of a light shielding material.
In the liquid crystal layer corresponding to the peripheral portion of the retardation layer, alignment disorder of liquid crystal molecules may occur due to a step between the retardation layer and the first alignment film. Since the desired display cannot be performed in the portion where the alignment is disturbed, the display quality of the liquid crystal device may be impaired.
If the first light-shielding part is made of a light-shielding material at the peripheral part of the retardation layer, the first light-shielding part can conceal the part where the alignment is disturbed. It is possible to prevent the display quality from being impaired.

Further, the second intermediate layer, a between the first alignment film and the second alignment film, only a portion of the area phase difference layer is not provided, it is provided selectively preferred .
In this case, since the contact area between the second intermediate layer and the first alignment film is smaller than in the case where the entire surface is provided between the first alignment film and the second alignment film, the in-plane stress is small. Become. Therefore, inconveniences when the in-plane stress is large, that is, a reduction in processing accuracy, a decrease in yield, and the like can be avoided, and a favorable liquid crystal device can be obtained.

The second intermediate layer preferably has a second light transmitting portion made of light-transmitting material, the second transparent portion is preferably made of ITO or SnO _2. In this way, since light can be transmitted through the second light transmitting part, the second light transmitting part can be used as a display area, and the display area is prevented from becoming narrow. If the second light-transmitting portion made of ITO or SnO ₂ is used, the second light-transmitting portion having sufficient affinity for the second alignment film made of a normal alignment film material as described above can be obtained. A highly reliable liquid crystal device can be obtained.

An electronic apparatus according to the present invention includes the above-described liquid crystal device according to the present invention.
As described above, since the liquid crystal device of the present invention is satisfactory, an electronic apparatus including the liquid crystal device is also satisfactory.

  Hereinafter, although one embodiment of the present invention is described, the technical scope of the present invention is not limited to the following embodiment. In the following description, various structures are illustrated using drawings, but in order to show the characteristic parts of the structures in an easy-to-understand manner, the structures in the drawings are shown in different sizes and scales from the actual structures. There is.

  Note that the liquid crystal device according to the present embodiment is an FFS (of the horizontal electric field type in which an image is displayed by applying an electric field (lateral electric field) in the substrate surface direction to liquid crystal molecules and controlling the azimuth angle of the liquid crystal molecules. (Fringe Field Switching) method is adopted. The color liquid crystal device includes a color filter, and one pixel includes three sub-pixels that emit light of each color of R (red), G (green), and B (blue). Hereinafter, a display area which is a minimum unit constituting display is referred to as a sub-pixel area, and a display area including a set of (R, G, B) sub-pixels is referred to as a pixel area.

  FIG. 1 is a circuit configuration diagram of a sub-pixel 200 constituting the liquid crystal device 100 of the present embodiment. A large number of subpixels 200 are arranged in a matrix, and as shown in FIG. 1, the pixel electrode 9 and the TFT 30 are formed in each subpixel 200. The TFT 30 is a switching element that controls switching of the sub-pixel 200. The data line 6 a extending from the data line driving circuit 101 is electrically connected to the source of the TFT 30, and the pixel electrode 9 is electrically connected to the drain of the TFT 30. The data line driving circuit 101 supplies image signals S1, S2,..., Sn to the sub-pixels 200 via the data line 6a.

  A scanning line 3 a extending from the scanning line driving circuit 102 is electrically connected to the gate of the TFT 30. The scanning signals G1, G2,..., Gm supplied from the scanning line driving circuit 102 to the scanning line 3a at a predetermined timing are applied to the gates of the TFTs 30 in this order in a line-sequential manner. When the scanning signals G1 to Gm are applied to the gate of the TFT 30, the gate and source of the TFT 30 are turned on for a certain period, and the image signals S1 to Sn supplied from the data line 6a are applied to the pixel electrode 9 at a predetermined timing. It is to be written.

  The pixel electrode 9 faces a common electrode described later, and a capacitor is formed between the pixel electrode 9 and the common electrode. Further, the sub-pixel 200 is connected to the capacitor line 3 b provided in parallel with the scanning line 3 a, and a storage capacitor 70 is provided between the drain of the TFT 30 and the pixel electrode 9. The capacitor and the storage capacitor 70 are connected in parallel, and image signals S1 to Sn of a predetermined level written in the pixel electrode 9 are held in the capacitor and the storage capacitor 70 for a certain period. Since the storage capacitor 70 is provided, the image signal held in the capacitor does not leak.

FIG. 2 is an enlarged plan view showing one of the sub-pixels 200. In the present embodiment, the sub-pixel 200 has a rectangular sub-pixel region S having a short side and a long side. Here, the direction parallel to the short side is defined as the X direction, and the direction parallel to the long side. Is the Y direction.
The sub-pixel region S includes a rectangular reflective display region R and a rectangular transmissive display region T arranged in the Y direction. Here, in the Y direction, the side where the reflective display region R is located is the Y negative direction, and the side where the transmissive display region T is located is the Y positive direction.
The sub-pixel 200 is provided in the pixel electrode 9 provided over the reflective display region R and the transmissive display region T, the common electrode 19 provided so as to cover the pixel electrode 9 in a plan view, and the reflective display region R. And a reflective layer 29. In addition, columnar spacers 40 for holding a first substrate and a second substrate, which will be described later, spaced apart from each other at a predetermined interval, stand at corners of the sub-pixel 200, for example, corners in the X negative direction and the Y positive direction. It is installed. The columnar spacer 40 may be provided in the gap between the sub-pixels 200.

The pixel electrode 9 is made of a transparent conductive material such as ITO (indium tin oxide), and has a ladder shape in a plan view. Specifically, it is configured to include a plurality of (15 in the drawing) strip-like portions 9c that extend in the positive X direction and are inclined in the positive Y direction, and a frame-like portion 9a. The plurality of strip-like electrodes 9c are arranged in the Y-axis direction at equal intervals in parallel to each other, and are connected to the inside of the frame-like portion 9a at each end.
The common electrode 19 is a conductive film made of a transparent conductive material such as ITO, and has a rectangular shape that is long in the Y direction in a plan view. In the present embodiment, the common electrode 19 is provided so as to cover the reflective layer 29.
The reflective layer 29 is composed of a light reflective metal film such as aluminum or silver, or a dielectric laminated film (dielectric mirror) in which dielectric films (SiO ₂ and TiO ₂ etc.) having different refractive indexes are laminated. It is. The liquid crystal device 100 preferably has a function of scattering the reflected light from the reflective layer 29, whereby the visibility of the reflective display can be improved.

  In addition to the configuration in which the common electrode 19 and the reflective layer 29 are provided side by side, a configuration in which a transparent electrode made of a transparent conductive material and a reflective electrode made of a light-reflective metal material are divided in a plane, that is, transmissive A transparent electrode disposed corresponding to the display area and a reflective electrode disposed corresponding to the reflective display area are provided, and both electrodes are electrically connected to each other between the transmissive display area and the reflective display area (boundary portion). What is connected to can also be adopted. In this case, the transparent electrode and the reflective electrode constitute a common electrode that generates an electric field between the pixel electrode and the reflective electrode also functions as a reflective layer in the sub-pixel region.

  In the sub-pixel 200, a data line 6a extending in the Y direction, a scanning line 3a extending in the X direction, and a capacitor line 3b extending in parallel to the scanning line 3a adjacent to the scanning line 3a are formed. A TFT 30 is provided in the vicinity of the intersection of the data line 6a and the scanning line 3a. The TFT 30 includes a semiconductor layer 35 made of an island-shaped amorphous silicon film partially formed in the planar region of the scanning line 3a, a source 6b formed partially overlapping the semiconductor layer 35, and a drain 32. And. The scanning line 3 a functions as a gate of the TFT 30 at a position overlapping the semiconductor layer 35 in plan view.

  The source 6b of the TFT 30 has a substantially L shape in plan view extending from the data line 6a and extending to the semiconductor layer 35, and the drain 32 extends from the semiconductor layer 35 toward the pixel electrode 9 and extends to the pixel electrode 9 side. And are electrically connected. A contact portion of the pixel electrode 9 is disposed on the capacitor electrode 31, and the capacitor electrode 31 and the pixel electrode 9 are electrically connected via a pixel contact hole 45 provided at a position where they overlap in a plane. Has been. The capacitor electrode 31 is disposed in the plane area of the capacitor line 3b, and a storage capacitor 70 is formed at this position using the capacitor electrode 31 and the capacitor line 3b facing each other in the thickness direction.

  FIG. 3 is a partial cross-sectional configuration diagram along line AA in FIG. 2. The liquid crystal device 100 includes a first substrate 20 and a second substrate 10 that are arranged to face each other, and a liquid crystal layer 50 that is sandwiched between these substrates. The edge part of the 1st board | substrate 20 and the edge part of the 2nd board | substrate 10 are bonded together by the sealing material (not shown), and the liquid crystal layer 50 is sealed between these board | substrates. A polarizing plate 24 is provided on the outer surface side of the first substrate 20 (the side opposite to the liquid crystal layer 50), and a polarizing plate 14 is provided on the outer surface side of the second substrate 10. A backlight (illumination device) 90 including a light source, a light guide plate 91, and a reflection plate 92 is provided on the outer surface side of the polarizing plate 14.

  The second substrate 10 has a transparent substrate 10A made of glass, quartz, plastic, or the like as a base, and scanning lines 3a and capacitance lines 3b are formed on the inner surface side (liquid crystal layer 50 side) of the transparent substrate 10A. A gate insulating film 11 is formed to cover the scanning line 3a and the capacitor line 3b. A semiconductor layer 35 is selectively formed on the gate insulating film 11, and a source 6 b and a drain 32 are formed so as to partially run over the semiconductor layer 35. A capacitor electrode 31 is formed integrally with the drain 32 on the opposite side of the drain 32 from the source 6b. The semiconductor layer 35 is disposed to face the scanning line 3 a via the gate insulating film 11, and the scanning line 3 a functions as a gate of the TFT 30 in the facing region. The capacitor electrode 31 is disposed opposite to the capacitor line 3b via the gate insulating film 11, and a storage capacitor 70 using the gate insulating film 11 as a dielectric film is disposed in a region where the capacitor electrode 31 and the capacitor line 3b are opposed to each other. Is formed.

  The first interlayer insulating film 12 is formed so as to cover the semiconductor layer 35, the source 6 b, the drain 32, and the capacitor electrode 31. A resin layer 39 such as an acrylic resin is formed on the first interlayer insulating film 12 in the reflective display region R, and a reflective layer 29 is formed on the resin layer 39. A common electrode 19 is formed so as to cover the reflective layer 29 and the first interlayer insulating film 12. The resin layer 39 has a concavo-convex shape on the surface thereof, and the reflective layer 29 formed thereon also has a concavo-convex shape, whereby the reflective layer 29 emits light emitted from the liquid crystal layer 50 side. It reflects and scatters.

  A second interlayer insulating film 13 made of silicon oxide or the like is formed so as to cover the common electrode 19. A pixel electrode 9 made of a transparent conductive material such as ITO is formed on the surface of the second interlayer insulating film 13 on the liquid crystal layer 50 side. An alignment film 18 made of polyimide or the like is formed so as to cover the pixel electrode 9 and the second interlayer insulating film 13.

  Further, a pixel contact hole 45 penetrating the first interlayer insulating film 12 and the second interlayer insulating film 13 and reaching the capacitor electrode 31 is formed, and a part of the pixel electrode 9 (contact portion) is formed in the pixel contact hole 45. ) Is embedded, and the pixel electrode 9 and the capacitor electrode 31 are electrically connected. The common electrode 19 has an opening corresponding to the region where the pixel contact hole 45 is formed, and the pixel electrode 9 and the capacitor electrode 31 are electrically connected through the opening, and the common electrode 19 19 and the pixel electrode 9 are configured not to be short-circuited.

  The first substrate 20 has a transparent substrate 20A made of glass, quartz, plastic or the like as a base, and a color filter layer 21 is formed on the inner surface side (liquid crystal layer 50 side) of the transparent substrate 20A. In the present embodiment, the color filter layer 21 has colored portions corresponding to each of red, green, and blue, and these colored portions are arranged such that those corresponding to red, green, and blue are periodically arranged. Has been placed. Further, one of the sub-pixels 200 corresponds to one of the colored portions, and one colored portion corresponds to the first color material portion corresponding to the transmissive display region T and the first corresponding to the reflective display region R. It consists of two color material parts. The first color material portion has a chromaticity greater than the chromaticity of the second color material region, the display light is transmitted through the first color material portion once, and the display light is the first color material portion. The chromaticity of the display light is the same between the reflective display region R that transmits the two color material portions twice. The color filter layer 21 can also be formed on the second substrate 10 side. Further, a portion between the colored portions may be a light shielding portion, and wiring such as the TFT 30 and the scanning line 3a can be prevented from being visually recognized.

  A protective film 22 made of acrylic resin or the like is provided on the inner surface side of the color filter layer 21, and the color filter layer 21 is protected by the protective film 22. A first alignment film 23 is provided on the inner surface side of the protective film 22, and a retardation layer 25 is formed in the reflective display region R on the inner surface side of the first alignment film 23. A first intermediate layer 26 is provided on the inner surface side of the peripheral portion of the retardation layer 25, and a second intermediate layer 27 is provided on the inner surface side of the peripheral portion of the retardation layer 25. A second alignment film 28 is provided so as to cover the first alignment film 23, the retardation layer 25, the first intermediate layer 26, and the second intermediate layer 27.

  FIG. 4 is an exploded perspective view schematically showing the main part of the first substrate 20. 4 is a perspective view with the polarizing plate 24 side of the base body 20B made of the polarizing plate 24, the transparent substrate 20A, the color filter layer 21, and the protective film 22 as the bottom surface, and the X direction and Y direction shown in FIG. The direction and the Z direction orthogonal to these are shown. As the Z direction, the inner surface side that is the liquid crystal layer 50 side is defined as a positive Z direction, and the opposite direction is defined as a negative Z direction.

As shown in FIG. 4, the first alignment film 23 is provided so as to cover the entire surface of the base body 20 </ b> B in the reflective display region R and the transmissive display region T. The first alignment film 23 is made of polyimide or the like and has an orientation, and functions to impart refractive index anisotropy to the retardation layer 25 when the retardation layer 25 is formed.
The retardation layer 25 is provided on the first alignment film 23 in the reflective display region R and extends in the X direction. The phase difference layer 25 has a refractive index anisotropy, thereby giving a predetermined phase difference to incident light incident on the phase difference layer 25. In the present embodiment, the retardation layer 25 provides a phase difference of approximately ½ wavelength (λ / 2) to incident light.

  In the present embodiment, the retardation layer 25 also functions as a thickness adjusting layer for making the thickness of the liquid crystal layer 50 in the reflective display region R smaller than the thickness of the liquid crystal layer 50 in the transmissive display region T. It has become. In the transflective liquid crystal display device, incident light to the reflective display region R passes through the liquid crystal layer 50 twice, but incident light to the transmissive display region T passes through the liquid crystal layer 50 only once. As a result, if the retardation of the liquid crystal layer 50 is different between the reflective display region R and the transmissive display region T, a difference in light transmittance occurs, and a uniform image display cannot be obtained. Therefore, the multi-gap structure is realized by forming the retardation layer 25 so as to protrude toward the liquid crystal layer 50.

  Specifically, the layer thickness of the liquid crystal layer 50 in the reflective display region R is set to about half the layer thickness of the liquid crystal layer 50 in the transmissive display region T, and the liquid crystal layer 50 in the reflective display region R and the transmissive display region T Substantial retardation is set substantially the same. Thereby, a uniform image display can be obtained in the reflective display region R and the transmissive display region T. Further, in this way, the formation portion and the non-formation portion of the retardation layer 25, that is, the first alignment film 23 between the retardation layer 25 and the retardation layer 25, has a height corresponding to the thickness of the retardation layer 25. There is a difference in level.

  In the present embodiment, the first intermediate layer 26 is selectively provided only on a part of the retardation layer 25 (Z positive direction side). More specifically, they are provided only in the peripheral portion of the retardation layer 25, that is, extending in the X direction so as to cover the Y positive direction end and the Y negative direction end on the upper surface of the retardation layer 25. The second intermediate layer 27 is selectively provided only on a part of the first alignment film 23 in the peripheral portion of the retardation layer 25. More specifically, the first alignment film 23 is formed in a strip shape and extends in the X direction along the side surface of the retardation layer 25 that forms a step between the retardation layer 25 and the first alignment film 23. In the case where a plurality of subpixel regions are connected in the X direction, the first intermediate layer 26 and the second intermediate layer 27 may be provided over the plurality of subpixel regions.

  The first intermediate layer 26 and the second intermediate layer 27 have affinity for the liquid material that is the material for forming the second alignment film 28. As a material of the first intermediate layer 26 and the second intermediate layer 27, for example, when the second alignment film 28 is made of polyimide like a normal alignment film, it is provided close to the alignment film in a general liquid crystal device. The material of the member to be used can be used. That is, the liquid material of the alignment film containing polyimide is adjusted in composition and the like so that the alignment film can be satisfactorily formed, and has an affinity for the base of the alignment film forming portion. Therefore, if the material of the member is used as the material of the first intermediate layer 26 and the second intermediate layer 27, it will surely have an affinity for the alignment film material.

Specific materials for the first intermediate layer 26 and the second intermediate layer 27 include light-transmitting conductive inorganic materials such as ITO and SnO ₂ used for electrodes and the like, and SiO ₂ used for insulating members and the like. Insulating inorganic materials having translucency such as SiON, SiN, etc., light shielding inorganic materials such as Cr and Cu used for light shielding parts, and acrylic resins used for overcoat materials such as the protective film 22 An organic material etc. are mentioned.

The above materials can be appropriately selected and used. For example, if a part of the first intermediate layer 26 is a first light transmitting part made of a transparent material, this part can contribute to display. Therefore, the display area can be made wider than when a light shielding material is used. Similarly, if the second intermediate layer 27 is partly a second light transmitting portion made of a transparent material, the display area can be widened.
Further, for example, if the portion covering the step portion between the phase difference layer 25 and the first alignment film 23 is made of a light-shielding material, it is possible to hide the display defect portion due to the liquid crystal molecule alignment disorder caused by the step. Therefore, it is possible to avoid a decrease in display quality. Specifically, the first intermediate layer 26 that covers the end of the retardation layer 25 in the Y positive direction is a first light shielding portion made of a light shielding material, or the Y positive direction of the retardation layer 25 is The above-mentioned effect can be obtained by using the second intermediate layer 27 that covers the first alignment film 23 in a strip shape along the side wall as a second light shielding portion made of a light shielding material.
In the present embodiment, the first intermediate layer 26 and the second intermediate layer 27 are made of ITO. That is, the first intermediate layer 26 is composed of only the first light transmitting part, and the second intermediate layer 27 is composed of only the second light transmitting part.

  The second alignment film 28 is formed by solidifying a liquid material (liquid material), and aligns the liquid crystal molecules of the liquid crystal layer 50 at a predetermined azimuth angle. The second alignment film 28 is formed by, for example, applying a liquid polyimide organic material (liquid material) and solidifying it by thermosetting or the like. Further, as will be described in detail in [Production Example] described later, the second alignment film 28 is formed by applying the liquid material well by providing the first intermediate layer 26 and the second intermediate layer 27. , Have been good.

  In the present embodiment, the liquid crystal layer 50 shown in FIG. 3 contains liquid crystal molecules having positive dielectric anisotropy, and in an initial alignment state where no electric field is generated between the pixel electrode 9 and the common electrode 19. The retardation Δnd of the liquid crystal layer 50 in the transmissive display region T gives a phase difference of approximately ½ wavelength, and the retardation Δnd of the liquid crystal layer 50 in the reflective display region R is approximately ¼ wavelength (λ / 4) is provided. The light passing through the liquid crystal layer 50 in the reflective display region R is substantially given a phase difference of about ½ wavelength by being given a phase difference of about ¼ wavelength before and after reflection. Is done. As described above, the light passing through the reflective display region R and the light passing through the transmissive display region T have substantially the same retardation, so that a uniform image display can be obtained in the transmissive display region T and the reflective display region R. It has become.

  The arrangement of the optical axes of the optical members of the liquid crystal device 100 is as follows. The transmission axis of the polarizing plate 14 and the transmission axis of the polarizing plate 24 are orthogonal to each other. The transmission axis of the polarizing plate 24 is arranged in a direction that forms 45 ° with the main direction of the electric field generated between the pixel electrode 9 and the common electrode 19 (the direction orthogonal to the extending direction of the strip electrode 9c). The optical axis (slow axis) of the retardation layer 25 is disposed in a direction that forms 22.5 ° with the transmission axis of the polarizing plate 24. The rubbing direction of the alignment films 18 and 28 is parallel to the transmission axis of the polarizing plate 14. The rubbing direction of the alignment films 18 and 28 is not limited to this, but is a direction intersecting with the main direction of the electric field generated between the pixel electrode 9 and the common electrode 19. In the initial state, the liquid crystal molecules aligned in parallel along the rubbing direction are rotated and aligned toward the main direction of the electric field by applying a voltage between the pixel electrode 9 and the common electrode 19. Bright and dark display is performed based on the difference between the initial alignment state and the alignment state when a voltage is applied.

[Production example]
Next, regarding the method for manufacturing the liquid crystal device 100, an example of manufacturing the first substrate 20 including the characteristic portion of the present invention will be described.

  FIGS. 5A to 5D are diagrams showing cross-sectional process diagrams of a cross section in a plane orthogonal to the X direction shown in FIG. 4 for an example of the manufacturing method of the first substrate 20.

  A base body 20B is prepared in which a color filter layer 21 and a protective film 22 are sequentially formed on a transparent substrate 20A, and a polarizing plate 24 is formed on the opposite side of the transparent substrate 20A from the color filter layer 21. . The polarizing plate 24 may be formed in a later step. Then, as shown in FIG. 5A, a first alignment film 23 is formed on the protective film 22 of the base body 20B. Specifically, for example, a liquid polyimide organic material (liquid material) is formed on the protective film 22 by spin coating. Then, after this film is solidified by heat treatment or the like, the first alignment film 23 is formed by imparting orientation to the film solidified by, for example, a rubbing method or the like.

  Next, as illustrated in FIG. 5B, the retardation layer 25 is formed on the first alignment film 23. Specifically, a material containing a liquid crystal material such as a liquid crystal monomer or a liquid crystal oligomer is formed on the first alignment film 23 by a spin coating method. The formed liquid crystal material is brought into a predetermined alignment state by the first alignment film 23. Next, energy is applied to the film by ultraviolet irradiation or the like to polymerize a liquid crystal monomer or a liquid crystal oligomer. Thereby, the molecular structure of the polymer is maintained in a state in which the orientation is reflected, and has a refractive index anisotropy. Next, this polymer is patterned using a lithography technique, an etching technique, and the like to form the retardation layer 25.

  Next, as shown in FIG. 5C, the first intermediate layer 26 is selectively formed only on a part of the retardation layer 25, and a portion of the first alignment film along the side wall of the retardation layer 25 is formed. A second intermediate layer 27 is formed on 23. Specifically, for example, ITO is formed on the entire surface of the retardation layer 25 and the first alignment film 23 by a sputtering method. Then, this film is patterned by using a lithography technique and an etching technique to form the first intermediate layer 26 and the second intermediate layer 27. The first intermediate layer and the second intermediate layer are formed by selectively forming ITO on the retardation layer 25 and the first alignment film 23 by vapor deposition using a mask pattern such as a metal mask. You may do it.

  As described above, if the first intermediate layer 26 is formed only on a part of the retardation layer 25, the first intermediate layer 26 and the retardation layer 25 are formed more than when the first intermediate layer 26 is formed so as to cover the entire retardation layer 25. The contact area is reduced. Accordingly, the in-plane acting on the first intermediate layer 26 and the retardation layer 25 due to the difference in material between the first intermediate layer 26 and the retardation layer 25, the residual stress such as the thermal stress of the first intermediate layer 26, and the like. Stress can be reduced. Thereby, the distortion of the base body 20B due to the in-plane stress is reduced, and inconveniences such as being unable to carry on the line and lowering the processing accuracy are avoided. Further, since the in-plane stress acting on the retardation layer 25 can be reduced, distortion of the retardation layer 25 can be eliminated, and the retardation side 25 can function well. In addition, by selectively forming the second intermediate layer 27, the in-plane stress acting on the second intermediate layer 27 and the first alignment film 23 can be reduced. Therefore, the distortion of the base body 20B due to the in-plane stress is reduced, and the above-described disadvantage can be avoided.

  Next, as shown in FIG. 5D, a second alignment film 28 that covers the first alignment film 23, the retardation layer 25, the first intermediate layer 26, and the second intermediate layer 27 is formed. Specifically, for example, similarly to the formation of the first alignment film 23, a liquid polyimide organic material (liquid material) is formed by spin coating. The phase difference layer 25 may have a liquid repellency with respect to the liquid material due to a difference in material from the liquid material or a change in the surface state due to a process such as energy application at the time of formation. In addition, the first alignment film 23 may have liquid repellency with respect to the liquid material due to rubbing treatment, solidification treatment (heating treatment), or the like.

  According to a normal manufacturing method, the first intermediate layer and the second intermediate layer are not formed. Therefore, when the retardation layer and the first alignment film have liquid repellency with respect to the liquid material, the liquid material is applied evenly. It becomes difficult. In particular, at the step portion between the first alignment film and the retardation layer, the step coverage of the liquid material is impaired, and the liquid material is likely to be disconnected. When step breakage occurs, the liquid material is rounded by the surface tension into droplets and becomes discrete. For example, on the retardation layer, the liquid material approaches from the peripheral portion side to the central portion side, and on the first alignment film, the liquid material approaches from the peripheral portion of the retardation layer to the central portion of the first alignment film. End up.

  However, in the present invention, since the first intermediate layer 26 and the second intermediate layer 27 are formed, the corner of the stepped portion H that is the peripheral portion of the retardation layer 25 and the step that is the peripheral portion of the retardation layer 25. The liquid material wets and spreads on the upper surface of the part, and the step coverage is improved. Further, even when the step breakage occurs, the liquid material wets and spreads in the peripheral portion of the retardation layer 25, so that it is prevented from approaching the central portion of the first alignment film 23 due to surface tension. In addition, since the liquid material wets and spreads around the peripheral portion of the retardation layer 25, it is also possible to prevent the liquid material from approaching the central portion of the retardation layer 25. In this way, the liquid material can be applied without unevenness.

  Then, after the film on which the liquid material is formed is solidified by heat treatment or the like, the second alignment film 28 can be formed by imparting orientation to the solidified film by rubbing treatment or the like. Since the second alignment film 28 is coated with a liquid material without unevenness as described above, there is no defective formation portion such as a non-formed portion where the retardation layer 25 or the first alignment film 23 is exposed, and the second alignment film 28 is good. It has become.

  As described above, since the liquid crystal device of the present invention includes the first intermediate layer 26 and the second intermediate layer 27, the second alignment film 28 is favorable. Therefore, the liquid crystal molecules of the liquid crystal layer 50 can be in a desired orientation by the good second alignment film 28, and by applying a predetermined voltage between the pixel electrode 9 and the common electrode 19, the liquid crystal molecules of the liquid crystal layer 50 can be obtained. It becomes possible to control the orientation of molecules to a desired azimuth angle. As described above, the liquid crystal alignment failure and the light leakage due to the poor formation of the second alignment film do not occur, so that a desired display can be performed and the liquid crystal device is capable of high quality display.

  In addition, if the first intermediate layer 26 and the second intermediate layer 27 that are selectively provided as in the above-described embodiment, a decrease in processing accuracy, a decrease in yield, and the like are avoided in the manufacturing process of the first substrate 20. And a good liquid crystal device can be obtained. In addition, since the strain due to the in-plane stress of the retardation layer 25 can be reduced, this can function well, and a good liquid crystal device can be obtained.

[Modification]
In the above-described embodiment, the first intermediate layer 26 is provided only in the peripheral portion of the retardation layer 25 and the second intermediate layer 27 is provided only in the peripheral portion of the retardation layer 25 as an example. As described above, the arrangement and shape of the first intermediate layer 26 and the arrangement and shape of the second intermediate layer 27 can be changed without departing from the spirit of the present invention. For example, a configuration in which the first intermediate layer 26 is also provided in the central portion of the retardation layer 25 can be employed. Hereinafter, some modified examples will be described using examples in which the second intermediate layer 27 is deformed. However, the first intermediate layer 26 may be similarly modified.

  FIG. 6A is a perspective view schematically showing a first modification. Modification 1 is different from the above-described embodiment in that the second intermediate layer includes a plurality (four in the drawing) of belt-like portions 271, 272, 273, and 274. The belt-like portion 271 is provided in the peripheral portion of the retardation layer 25 as in the above embodiment, and the belt-like portions 272, 273, and 274 are arranged in parallel with the belt-like portion 271. Further, the strip portions 271, 272, 273, and 274 are arranged at equal intervals in the direction away from the retardation layer 25. As described above, by disposing the band-shaped portions 272, 273, and 274 in the central portion of the first alignment film 23, it is possible to prevent the liquid material from being repelled in the central portion of the first alignment film 23, which is favorable. The second alignment film 28 can be formed. For example, when the second intermediate layer is not provided in the central portion of the first alignment film 23, the liquid material is attracted from the central portion side of the liquid repellent first alignment film 23 to the affinity band-like portion 271 side. In addition, there is a possibility that a portion (flick) where the liquid material is not applied is generated in the central portion of the first alignment film 23, but such inconvenience is avoided.

  In addition, it can avoid that the area | region which contributes to a display area becomes narrow by making the strip | belt-shaped parts 272, 273, and 274 into the 2nd translucent part which each consists of a translucent material. In addition, although the belt-like portion 271 can be a second light-transmitting portion, when the second light-shielding portion made of a light-shielding material is used, liquid crystal molecule alignment disorder occurs in a portion corresponding to the stepped portion. But you can hide it. Thus, the structure which used the 2nd light transmission part and the 2nd light-shielding part together is also possible.

  FIG. 6B is a perspective view schematically showing a second modification. The second modified example is different from the above embodiment in that the second intermediate layer 27 includes a strip-shaped portion extending in a direction along the peripheral portion of the retardation layer 25 and a strip-shaped portion extending in a direction orthogonal to the strip-shaped portion. It is a point that is shaped.

  FIG. 6C is a perspective view schematically showing a third modification. The third modified example is different from the above embodiment in that the second intermediate layer is formed in the belt-like portion 271 provided in the peripheral portion of the retardation layer 25 and the central portion of the first alignment film 23 as in the above embodiment. It is the point comprised from the island-shaped part 272 provided. In this way, as in the first modification, the liquid material is prevented from being repelled at the center of the first alignment film 23, and a good second alignment film 28 can be obtained. Moreover, the structure which makes the strip | belt-shaped part 271 a 2nd light-shielding part and makes the island-shaped part 272 a 2nd light-transmissive part is also possible.

  FIG. 6D is a perspective view schematically showing a fourth modification. In the fourth modified example, as in the third modified example, the second intermediate layer includes a band-shaped portion 271 and an island-shaped portion. The fourth modification is different from the third modification in that a plurality of island-like parts 272a, 272b, and 273c smaller than the island-like part 272 of the third modification are provided in a plan view. By so doing, it is possible to obtain a good second alignment film 28 as in the third modification. In addition, since the contact area between each island-shaped portion 272a, 272b, 273c and the first alignment film 23 is smaller than the island-shaped portion 272 of the third modification, the island-shaped portions 272a, 272b, 273c The in-plane stress can be relaxed, and the distortion of the first substrate 20 can be reduced. Moreover, the structure which makes the strip | belt-shaped part 271 a 2nd light-shielding part and makes the island-shaped part 272 a 2nd light-transmissive part is also possible.

[Electronics]
FIG. 7 is a perspective configuration diagram of a mobile phone which is an example of an electronic apparatus provided with a liquid crystal device according to the present invention in a display portion. The mobile phone 1300 uses the liquid crystal device of the present invention as a small-size display portion 1301. A plurality of operation buttons 1302, an earpiece 1303, and a mouthpiece 1304.
The liquid crystal device of the first embodiment is not limited to the above mobile phone, but is an electronic book, personal computer, digital still camera, liquid crystal television, viewfinder type or monitor direct view type video tape recorder, car navigation device, pager, electronic notebook, calculator It can be suitably used as an image display means for devices such as word processors, workstations, videophones, POS terminals, touch panels, etc., and any electronic device can obtain a high-quality display.

It is a circuit block diagram of the sub pixel which comprises the liquid crystal device of this invention. It is a plane block diagram which expands and shows one of a sub pixel. It is a cross-sectional block diagram which shows the principal part of the liquid crystal device of this invention. It is a perspective view which shows typically the 1st board | substrate which comprises the liquid crystal device of this invention. (A)-(d) is sectional process drawing which shows a manufacture example. It is a perspective view which shows some modifications. It is a perspective view which shows an example of an electronic device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... 2nd board | substrate, 20 ... 1st board | substrate, 23 ... 1st alignment film, 25 ... Retardation layer, 26 ... 1st intermediate | middle layer, 27 ... 2nd intermediate | middle layer , 28 ... second alignment film, 50 ... liquid crystal layer, 100 ... liquid crystal device, R ... reflective display area, T ... transmissive display area

Claims (9)

A liquid crystal device having a reflective display area selectively provided in a display area,
A first substrate;
A second substrate facing the first substrate;
A liquid crystal layer sandwiched between the first substrate and the second substrate and containing liquid crystal molecules;
A first alignment film provided between the first substrate and the liquid crystal layer;
A retardation layer provided between the first alignment film and the liquid crystal layer in the reflective display region, and provided with refractive index anisotropy by the first alignment film;
A second alignment film provided to cover the first alignment film and the retardation layer and align liquid crystal molecules of the liquid crystal layer in a predetermined direction;
The second alignment film is formed by solidifying a liquid material,
Of the region where the retardation layer is provided, it is at least between the retardation layer and the second alignment film at the peripheral edge of the retardation layer, and is selective only to a part on the retardation layer. In addition, a first intermediate layer having an affinity for the liquid material is provided,
A second material having an affinity for the liquid material at least between the first alignment film and the second alignment film in the periphery of the retardation layer in the region where the retardation layer is not provided. A liquid crystal device comprising an intermediate layer. 2. The liquid crystal device according to claim 1, wherein the first intermediate layer includes a first light transmitting portion made of a light transmitting material. The first translucent part is made of ITO or SnO. ₂ The liquid crystal device according to claim 2, comprising: The said 1st intermediate | middle layer has the 1st light-shielding part which consists of a light-shielding material in the part provided in the peripheral part of the said phase difference layer, The any one of Claims 1-3 characterized by the above-mentioned. The liquid crystal device according to item. The second intermediate layer is selectively provided only in a part of the region between the first alignment film and the second alignment film where the retardation layer is not provided. The liquid crystal device according to claim 1, wherein the liquid crystal device is a liquid crystal device. 6. The liquid crystal device according to claim 1, wherein the second intermediate layer includes a second light transmitting portion made of a light transmitting material. The second light transmitting part is made of ITO or SnO. ₂ The liquid crystal device according to claim 6, comprising: The said 2nd intermediate | middle layer has the 2nd light-shielding part which consists of a light-shielding material in the part provided in the peripheral part of the said phase difference layer, The any one of Claims 1-7 characterized by the above-mentioned. The liquid crystal device according to item. An electronic apparatus comprising the liquid crystal device according to claim 1.

Images