JP3699601B2 - Liquid crystal element - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid crystal element.
[0002]
[Prior art]
Since liquid crystal elements are thin, lightweight, and have excellent power saving, they have been used in many fields. At present, the use as a display element is particularly conspicuous, and it is used as a display element of a portable electronic device to fully utilize its characteristics. Other than the use as a display element or a display device, there is a use as a light control means or a large-diameter light modulation means.
[0003]
A liquid crystal element generally has a structure in which a liquid crystal composition is sandwiched between two glass substrates. However, when the substrate is a polymer film, weight reduction and impact resistance are improved. Therefore, it becomes more suitable for portable use.
[0004]
[Problems to be solved by the invention]
By the way, when a polymer film is used as a substrate of a liquid crystal element, some external stimulus may be a trigger to generate bubbles in the liquid crystal element. This phenomenon may be observed even in a liquid crystal element using a glass substrate although the frequency is low. As described above, when bubbles are generated in the liquid crystal element, the portion where the bubbles are generated is not filled with liquid crystal, so that the portion does not function as a liquid crystal element. there were.
[0005]
An object of the present invention is to provide a liquid crystal element capable of preventing bubble generation in the liquid crystal element.
[0006]
It is another object of the present invention to provide a liquid crystal element capable of quickly eliminating bubbles even when bubbles are generated.
[0007]
[Means for Solving the Problems]
To achieve the above object, a first aspect of the present invention, to form a closed space between the upper and lower substrates, a liquid crystal element formed by filling a liquid crystal composition in the closed space, wherein A polymer film substrate having flexibility is used for the upper substrate and the lower substrate, and the pressure inside the liquid crystal element is increased by pressurizing the non-display portion of the liquid crystal element.
[0009]
The invention described in claim 2 is characterized in that the liquid crystal element according to claim 1 is further provided with a pressure adjusting means for adjusting the degree of pressure inside the liquid crystal element.
[0010]
According to a third aspect of the present invention, in the liquid crystal element according to the first or second aspect , a spacer for maintaining a constant gap between the upper substrate and the lower substrate is provided between the upper substrate and the lower substrate. The spacer is adhered or adhered to both the upper substrate and the lower substrate at least in the display portion so that the space between the upper substrate and the lower substrate in the display portion is not widened by pressing. It is characterized by being.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
1 and 2 are diagrams showing an example of the configuration of a general liquid crystal element. 1 is a schematic plan view, and FIG. 2 is a cross-sectional view. Referring to FIG. 1 and FIG. 2, in this liquid crystal element, an upper substrate 4 and a lower substrate 6 are bonded together by a sealing agent 1, and a distance (gap) between the upper substrate 4 and the lower substrate 6 is determined by a spacer 5. Evenly held. In addition, a liquid crystal composition 7 injected from the sealing port 2 is filled between the upper substrate 4 and the lower substrate 6. Note that the liquid crystal composition 7 is conventionally sealed with a kind of an adhesive called an encapsulant in order to prevent the outside air from flowing in from the encapsulant 2 and the liquid crystal composition 7 from flowing out. ing.
[0012]
In the configuration of the liquid crystal element, the inventor of the present application indicates that bubbles are generated when the pressure inside the liquid crystal element is higher than the outside and the liquid crystal composition naturally flows out when the liquid crystal element is opened. It has been found that even if it occurs, it disappears within a short time.
[0013]
In view of this, the present invention provides a liquid crystal element formed by forming a closed space between the upper substrate 4 and the lower substrate 6 and filling the closed space with the liquid crystal composition 7. The internal pressure is higher than the outside . As described above, since the pressure inside the liquid crystal element is higher than the outside , bubbles are hardly generated, and even if they are generated, they can be eliminated within a short time.
[0014]
FIG. 3 is a diagram showing a specific example of the liquid crystal element of the present invention. In the example of FIG. 3, the liquid crystal element is provided with a non-display portion 8 and a display portion 9. In this case, in the present invention, the non-display portion 8 of the liquid crystal element can be pressurized by a mechanical force from the outside of the liquid crystal element to create a state where the pressure inside the liquid crystal element is higher than the outside. Thereby, it is difficult to generate bubbles, and even when they are generated, a state of disappearing within a short time can be intentionally created. In FIG. 3, the position of the non-display portion 8 is an example, and is not limited to the position in the drawing. That is, the non-display portion 8 can be provided at an arbitrary position.
[0015]
By the way, when the upper substrate 4 or the lower substrate 6 is a highly rigid substrate such as a glass substrate, the gap between the upper substrate 4 and the lower substrate 6 changes even in the pressurized peripheral portion, which is the display unit 9. If this is the case, another problem of display unevenness will occur. In order to avoid this problem, the non-display portion 8 of the substrate may be made of a flexible material. That is, a part of members constituting the liquid crystal element such as the upper substrate 4 and the lower substrate 6 may be formed of a soft material, that is, a flexible material. At this time, the change in the gap between the upper substrate 4 and the lower substrate 6 of the display unit 9 can be suppressed, and the influence on the display performance can be reduced.
[0016]
FIG. 4 is a diagram illustrating a configuration example of a liquid crystal element in which a part of members constituting the liquid crystal element is formed of a flexible material. In FIG. 4, the alignment film and the transparent electrode are omitted. In the liquid crystal element of FIG. 4, a part of the upper substrate 4 (indicated by reference numeral 22) is a thin film.
[0017]
FIG. 5 is a diagram showing another configuration example of the liquid crystal element in which a part of the members constituting the liquid crystal element is formed of a flexible material. In the liquid crystal element of FIG. 5, a thin film portion 22 is formed by bonding a thin film to the end portion of the upper substrate 4. In this case, the thin film portion 22 may be formed by forming a hole in a part of the upper substrate 4 and attaching a thin film in such a manner as to cover the same.
[0018]
In the configuration example of FIG. 4 or FIG. 5, the thickness of the thin film portion 22 is approximately 50 microns or less when a general polymer is used. Is obtained.
[0019]
The thin film portion as described above can be formed on the lower substrate 6, and the thin film portion 22 formed on the upper substrate 4 or the lower substrate 6 can be formed by etching the substrate or as described above. Can be produced by pasting together.
[0020]
Furthermore, a liquid crystal element produced using a polymer film substrate for both the upper substrate 4 and the lower substrate 6 is excellent in portability and impact resistance, and is particularly preferable.
[0021]
Specifically, flexible materials that can be used as a substrate of a liquid crystal element include polyethylene terephthalate, polycarbonate, polyethersulfone, polyarylate, polyolefin, polyethylene naphthalate, and the like.
[0022]
Furthermore, as shown in FIG. 6, by making the shape of the portion 10 to be pressurized so that the amount of liquid crystal entering the interior is larger than that of other portions, the range in which pressure can be applied can be expanded. The pressurized state can be maintained by holding means (not shown) such as a clamp.
[0023]
Note that when the range in which pressure can be applied is expanded as shown in FIG. 6, the substrate is easily deformed in a liquid crystal element formed using a flexible substrate. The gap between the lower substrate 6 and the lower substrate 6 (for example, the distance between the upper substrate 4 and the lower substrate 6 in the display portion 8) increases, and it is difficult to return to the original uniform gap. In order to prevent this, it is necessary to hold the upper substrate 4 and the lower substrate 6 firmly. For example, the spacer 5 is coated with an adhesive or a pressure-sensitive adhesive, and the spacer 5 is adhered or adhered to the upper substrate 4 or the lower substrate 6 so that the distance between the upper substrate 4 and the lower substrate 6 does not become larger than a desired distance. can do.
[0024]
Furthermore, in this case, the shape of the spacer 5 is preferably not a spherical shape but a rectangular parallelepiped that has a large contact area with the upper substrate 4 and the lower substrate 6.
[0025]
In this way, by fixing the spacer 5 between the upper substrate 4 and the lower substrate 6, even when a flexible substrate is used, the thickness of the liquid crystal layer is made constant, and high-quality liquid crystal that is less likely to generate bubbles. An element can be provided.
[0026]
Further, when the range in which pressure can be applied is expanded as described above, it is necessary to adjust the degree of pressure while checking the gap between the upper substrate 4 and the lower substrate 6 so that display unevenness due to excessive pressure does not occur. May occur. For example, a screw mechanism 11 as shown in FIG. 7 can be used as the pressurization adjusting means for adjusting the degree of pressurization. Alternatively, a latched cam mechanism 12 as shown in FIG. 8 or a wedge mechanism 13 as shown in FIG. 9 can be used. By providing such pressure adjusting means, fine adjustment of the degree of pressurization can be performed. In other words, by providing adjustment means so that the pressure inside the liquid crystal element is not excessively pressurized, the generation of bubbles is prevented without causing display unevenness, and even when bubbles are generated, the bubbles disappear quickly. Can be made.
[0027]
Furthermore, as shown in FIG. 10, the degree of pressurization is such that the spacer 5 of the non-display part 8 is larger than the spacer 5 of the display part 9 and has elasticity, and the pressurization part 14 can be reversibly deformed. Can be adjusted more easily.
[0028]
The inventor of the present application compared a liquid crystal element manufactured using a polymer film substrate for the upper substrate 4 and the lower substrate 6 with a liquid crystal element using a glass substrate for the upper substrate 4 and the lower substrate 6. As a result, bubbles are more generated in the liquid crystal element manufactured using the polymer film substrate. For this reason, in the liquid crystal element produced using the polymer film substrate, the present invention is particularly preferable.
[0029]
【The invention's effect】
As described above, according to the invention described in claim 1, in the liquid crystal element formed by forming a closed space between the upper substrate and the lower substrate and filling the closed space with a liquid crystal composition, the on the substrate and the lower substrate is used a polymer film substrate having flexibility, the internal pressure of the liquid crystal element by pressurizing the non-display portion of the liquid crystal element is higher than the outside, display unevenness Bubbles can be prevented from being generated without being generated, and even when bubbles are generated, the bubbles can be quickly extinguished.
[0031]
Further, in the invention of claim 2, wherein, in the liquid crystal device according to claim 1 Symbol placement, further, by pressurizing means for adjusting the degree of pressure inside the liquid crystal element is provided, without generating display unevenness Generation of bubbles can be prevented, and even when bubbles are generated, the bubbles can be quickly extinguished.
[0032]
Further, in the invention according to claim 3 , by fixing the spacer between the upper substrate and the lower substrate, the thickness of the liquid crystal layer is made constant even when a flexible substrate is used, and bubbles are not easily generated. A quality liquid crystal element can be provided.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a configuration example of a general liquid crystal element.
FIG. 2 is a diagram illustrating a configuration example of a general liquid crystal element.
FIG. 3 is a diagram showing a specific example of a liquid crystal element of the present invention.
FIG. 4 is a diagram illustrating a configuration example of a liquid crystal element in which a part of members constituting the liquid crystal element is formed of a flexible material.
FIG. 5 is a diagram illustrating another configuration example of a liquid crystal element in which a part of members constituting the liquid crystal element is formed of a flexible material.
FIG. 6 is a diagram illustrating a configuration example of a liquid crystal element capable of expanding a pressurizing range.
FIG. 7 is a diagram illustrating an example of a pressure adjusting unit.
FIG. 8 is a diagram illustrating an example of a pressure adjusting unit.
FIG. 9 is a diagram illustrating an example of a pressure adjusting unit.
FIG. 10 is a diagram illustrating a configuration example of a liquid crystal element of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Sealant 2 Enclosing port 4 Upper board | substrate 5 Spacer 6 Lower board | substrate 7 Liquid crystal composition 8 Non-display part 9 Display part 10 Press part 11 Screw mechanism 12 Cam mechanism 13 Wedge mechanism 14 Press part 22 Thin film part

Claims (3)

In a liquid crystal element formed by forming a closed space between an upper substrate and a lower substrate and filling the liquid crystal composition in the closed space, a flexible polymer film substrate is formed on the upper substrate and the lower substrate. A liquid crystal element that is used, wherein a pressure inside the liquid crystal element is higher than the outside by pressurizing a non-display portion of the liquid crystal element. In the liquid crystal device according to claim 1 Symbol placement, further, a liquid crystal device characterized by pressure adjustment means for adjusting the degree of pressure inside the liquid crystal element is provided. 3. The liquid crystal device according to claim 1, wherein a spacer for maintaining a constant gap between the upper substrate and the lower substrate is sandwiched between the upper substrate and the lower substrate, and also by pressurization. The liquid crystal element, wherein the spacer is adhered or adhered to both the upper substrate and the lower substrate at least in the display portion so that a distance between the upper substrate and the lower substrate in the display portion is not widened.

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