Liquid crystal device

Abstract

To provide a liquid crystal device that can prevent a change in the thickness of a liquid crystal layer against bending and a strong stress load, and maintain image display with high image quality and without distortion of a display image.SOLUTION: A liquid crystal device has at least a first substrate having flexibility and formed of visible light transmissive material, a second substrate having flexibility, a liquid crystal layer arranged between the first substrate and the second substrate, and a hollow body formed of the visible light transmissive material and filled therein with liquid crystal. The liquid crystal layer is formed by arranging the plurality of hollow bodies.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a liquid crystal device having bendable flexibility.

Background Art

[0002] Liquid crystal display devices are widely used as display screens for devices such as PCs and smartphones because they are thin, lightweight, and have low power consumption. There is also known a bendable flexible liquid crystal display device in which a substrate or the like of such a liquid crystal display device is made of a flexible resin (see, for example, Patent Document 1).

[0003] As an example of a flexible liquid crystal display device, a thin sheet-type flexible device can be mentioned. The sheet-type flexible device is easy to carry in and install, and can be used, for example, not only as a flat plate but also as a display device on a predetermined surface (such as the front or side surface) of a curved household appliance or vehicle, or on the wall surface, column surface, floor surface, etc. of a building.

[0004] Such a liquid crystal-based sheet-type flexible device has many advantages, such as less deterioration of constituent materials due to moisture and oxygen in the atmosphere, high device reliability, and ease of achieving high brightness, full color, large screen size, and high definition.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] Conventional flexible liquid crystal display devices generally had a liquid crystal layer structure in which liquid crystal was encapsulated between two substrates and spacers were provided to maintain the distance between the two substrates. Therefore, when the flexible liquid crystal display device was curved, due to the difference in curvature between one substrate and the other substrate, a compressive force was generated at the center of the curved region and a tensile force was generated at the end of the curved region. For this reason, there were problems such as the thickness of the liquid crystal layer becoming non-uniform and the image quality being easily degraded, such as distortion of the displayed image.

[0007] In addition, when a flexible liquid crystal display device was installed in an environment where people were likely to collide, or when the flexible liquid crystal display device was installed on the floor or the like, the thickness became non-uniform due to repeated external forces, impacts, etc., causing the liquid crystal layer to partially dent, and there were also problems such as the image quality being easily degraded, such as distortion of the displayed image.

[0008] The present invention was proposed in view of the above problems, and an object thereof is to provide a liquid crystal device that can suppress changes in the thickness of the liquid crystal layer even under bending or strong stress loading and maintain high-quality image display without distortion of the displayed image.

Means for Solving the Problems

[0009] In order to solve the above problems, a liquid crystal device according to an embodiment of the present invention proposes the following means. (1) The liquid crystal device according to Aspect 1 of the present invention has at least a first substrate made of a visible light transmissive material and having flexibility, a second substrate having flexibility, a liquid crystal layer disposed between the first substrate and the second substrate, and a hollow body made of a visible light transmissive material and filled with liquid crystal inside (hollow portion), and the liquid crystal layer is characterized by being formed by arranging a plurality of the hollow bodies.

[0010] (2) Aspect 2 of the present invention is characterized in that, in the liquid crystal device of Aspect 1, the hollow body is cylindrical or polygonal cylindrical.

[0011] (3)Aspect 3 of the present invention is characterized in that in the liquid crystal device of Aspect 1 or 2, an alignment film for aligning the direction of the major axis of the liquid crystal molecules with order is disposed on the inner peripheral surface of the hollow body.

[0012] (4)Aspect 5 of the present invention is characterized in that in any one of the liquid crystal devices of Aspects 1 to 4, a common electrode made of a visible light transmissive conductive material is disposed in contact with one surface of the liquid crystal layer, and a plurality of pixel electrodes corresponding to the respective hollow bodies are disposed in contact with the other surface or the one surface of the liquid crystal layer.

[0013] (5)Aspect 5 of the present invention is characterized in that in any one of the liquid crystal devices of Aspects 1 to 4, a first polarizing plate is disposed between the first base material and the liquid crystal layer, and a second polarizing plate having a polarization direction different from that of the first polarizing plate is disposed between the second base material and the liquid crystal layer.

[0014] (6)Aspect 6 of the present invention is characterized in that in any one of the liquid crystal devices of Aspects 1 to 5, a fixing portion for fixing the respective hollow bodies is formed between the hollow bodies adjacent to each other in the liquid crystal layer.

[0015] (7)Aspect 7 of the present invention is characterized in that in the liquid crystal device of Aspect 6, the fixing portion is made of a resin material.

[0016] (8)Aspect 8 of the present invention is characterized in that in any one of the liquid crystal devices of Aspects 1 to 7, a color filter is disposed between the first base material and the liquid crystal layer or between the second base material and the liquid crystal layer.

[0017] (9)Aspect 9 of the present invention is characterized in that in any one of the liquid crystal devices of Aspects 1 to 8, the second base material is made of a visible light transmissive material, and a backlight for irradiating illumination light toward the first base material is disposed on the outer surface side of the second base material.

[0018] (10)Aspect 10 of the present invention is characterized in that in any one of the liquid crystal devices of Aspects 1 to 8, a visible light reflecting layer is formed between the second substrate and the liquid crystal layer.

Advantages of the Invention

[0019] According to the present invention, it is possible to provide a liquid crystal device capable of suppressing changes in the thickness of the liquid crystal layer even under bending or strong stress loading and maintaining high-quality image display without distortion of the displayed image.

Brief Description of the Drawings

[0020]

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Mode for Carrying Out the Invention

[0021] Hereinafter, with reference to the drawings, a liquid crystal device according to an embodiment of the present invention will be described. Note that the following embodiments are specifically described to better understand the gist of the invention, and do not limit the present invention unless otherwise specified. In addition, the drawings used in the following description may show the main parts enlarged for convenience of clearly understanding the features of the present invention, and the dimensional ratios of each component are not necessarily the same as the actual ones.

[0022] FIG. 1 is a schematic cross-sectional view showing a liquid crystal device according to an embodiment of the present invention. FIG. 2 is a schematic diagram showing the hollow body arrangement and electrode configuration of the liquid crystal device of FIG. 1. The liquid crystal device 10 of the present embodiment is a transmissive flexible liquid crystal display device that can be curved with an arbitrary curvature in an arbitrary direction.

[0023] The liquid crystal device 10 includes at least a first substrate (substrate) 11 made of a flexible visible light transmissive material, a second substrate (substrate) 12 having flexibility, and a liquid crystal layer 13 disposed between the first substrate 11 and the second substrate 12.

[0024] In this embodiment, a color filter 14, a first polarizing plate 15, and a common electrode 16 are sequentially disposed between the first substrate 11 and the liquid crystal layer 13. Also, a second polarizing plate 17 and a plurality of pixel electrodes 18, 18... are sequentially disposed between the second substrate 12 and the liquid crystal layer 13.

[0025] Furthermore, a backlight 19 that irradiates illumination light toward the first substrate 11 is disposed on the outer surface side of the second substrate 12.

[0026] The first substrate 11 is composed of, for example, a bendable resin film. Specifically, examples include a polyimide resin film, a polyethylene terephthalate resin film, a polypropylene resin film, a polystyrene resin film, a polycarbonate resin film, a polyamide resin film, and the like. It is preferable that the resin film constituting the first substrate 11 has transparency that can transmit light in the visible light region (about 360 nm to 830 nm) with low loss.

[0027] The second substrate 12 is composed of, for example, a bendable resin film. Specifically, examples include a polyimide resin film, a polyethylene terephthalate resin film, a polypropylene resin film, a polystyrene resin film, a polycarbonate resin film, a polyamide resin film, and the like.

[0028] In a transmissive liquid crystal device 10 such as this embodiment, it is preferable that the resin film constituting the second substrate 12 has transparency that can transmit illumination light from the backlight 19, for example, white light, with low loss.

[0029] In the case of a reflective liquid crystal device that uses external light incident from the first substrate 11 as illumination light without using the backlight 19, the second substrate 12 can also be formed of a light-shielding material.

[0030] The liquid crystal layer 13 has a plurality of arranged hollow bodies (microtubes) 20, 20... and a fixing part 22. The inside (hollow part) of the hollow body 20 is filled with a liquid crystal Q. The fixing part 22 is formed between the plurality of hollow bodies 20.

[0031] The hollow body 20 of the present embodiment is formed of a visible light transmissive material having a hollow cylindrical shape (including an elliptical cylindrical shape). For example, as the hollow body 20, it is preferable to use a tube made of a resin that has deformation resistance and resilience and is transparent. Specific constituent materials of the hollow body 20 include, for example, silicone resin (silicone rubber), polymethylpentene resin (PMP), and fluororesin (PFA), all of which also serve as the function of an "alignment film". Among these resins, it is preferable to use those having a high visible light transmittance and a low refractive index with an appropriate molecular weight.

[0032] The size of one hollow body 20 may be set according to the resolution of the liquid crystal device 10. For example, it may be such that the inner diameter is about 0.1 mm to 0.3 mm, the outer diameter is about 0.2 mm to 0.5 mm, and the thickness is about 0.1 mm to 0.4 mm. If the inner diameter of the hollow body 20 is made 0.1 mm or less, the resolution of the liquid crystal device 10 can be increased.

[0033] Note that at both ends (open ends) of each hollow body 20, an encapsulation layer (not shown) for preventing the outflow of the liquid crystal Q accommodated inside the hollow body 20 is formed. Such an encapsulation layer can use, for example, an epoxy-based adhesive.

[0034] Also, in the present embodiment, a hollow cylindrical tube is used as the hollow body 20, but the shape of the hollow body 20 is not limited to a cylindrical shape, and other cylindrical shapes can also be used. Other cylindrical shapes include, for example, polygonal cylindrical shapes such as a square cylindrical shape, a hexagonal cylindrical shape, and a triangular cylindrical shape.

[0035] Examples of the liquid crystal Q (liquid crystal molecules) include azoxy-based, azomethine-based, biphenyl-based, benzoic acid ester-based, cyclohexane-based, and heterocyclic compounds, but the present embodiment is not limited thereto. These liquid crystals can be used alone or in combination of two or more.

[0036] It has been found that the direction of the long axis of the liquid crystal molecules constituting the liquid crystal Q inside the hollow body 20, that is, the alignment direction, varies depending on the type of material of the hollow body 20. For example, in the hollow body 20 made of a fluororesin, in the initial alignment state without applying an electric field, as shown in FIG. 3(a), the longitudinal direction of the hollow body 20 is the alignment direction. On the other hand, in the hollow body 20 made of a silicone resin or a polymethylpentene resin, in the initial alignment state, as shown in FIG. 3(b), near the inner wall of the hollow body 20, the longitudinal direction of the hollow body 20 is the alignment direction, and in the inner part thereof, the alignment direction spreads radially from the center. Note that, as in the examples shown in FIGS. 3(a) and 3(b), the fact that a large number of liquid crystals Q are regularly aligned in the alignment direction corresponds to "with orderliness".

[0037] Note that such an initial alignment state of the liquid crystal molecules can be made in an arbitrary direction by forming an alignment film for controlling the alignment direction of the liquid crystal molecules in an arbitrary direction on the inner peripheral surface of the hollow body 20. In the present embodiment, the hollow body 20 is formed of a fluororesin so that the longitudinal direction of the hollow body 20 becomes the alignment direction of the liquid crystal molecules. In this embodiment, the fluororesin also serves as the "alignment film".

[0038] The hollow bodies 20 as described above may be formed in a number corresponding to the screen size along the X direction in FIG. 2. Each of these hollow bodies 20 forms a sub-pixel that emits each of the RGB colors of the color filter 14, and three hollow bodies 20 of each of these RGB colors constitute one pixel as a set.

[0039] The fixing part 22 is formed between the hollow bodies 20 arranged on one surface along the X direction. Even when the liquid crystal device 10 is bent, the plurality of hollow bodies 20 are fixed at predetermined positions without swinging.

[0040] As the constituent material of the fixing part 22, a resin material having bendable viscoelasticity and visible light transmittance that does not prevent the incidence and exit of light to and from the hollow body 20 is used. Further, as the constituent material of the fixing part 22, it is preferable to use a resin having a refractive index and visible light transmittance close to those of the constituent material of the hollow body 20.

[0041] The first polarizing plate 15 and the second polarizing plate 17 have different polarization directions from each other. In the present embodiment, the first polarizing plate 15 and the second polarizing plate 17 are made transmissive to polarized light rotated 90° from each other. Examples of the constituent materials of the first polarizing plate 15 and the second polarizing plate 17 include iodine polarizing plates, dye polarizing plates, and inorganic polarizing plates.

[0042] The common electrode 16 is formed in contact with one surface of the liquid crystal layer 13, that is, the surface on the side of the first base material 11 in the present embodiment. The common electrode 16 is made of a visible light transmissive conductive material and is formed so as to cover the plurality of hollow bodies 20.

[0043] In the present embodiment, in order to emit the video light formed by the illumination light emitted from the backlight 19 passing through the liquid crystal layer 13 to the outside from the first base material 11, the common electrode 16 needs to have visible light transmittance.

[0044] Examples of the visible light transmissive conductive material used for the common electrode 16 include oxides composed of indium (In) and tin (Sn) (ITO), oxides of tin (Sn) (SnO2), oxides composed of indium (In) and zinc (Zn) (IZO), and dispersions of polyethylenedioxythiophene and polystyrenesulfonic acid (PEDOT / PSS). Among these, since PEDOT / PSS has high flexibility, it can be particularly preferably applied to a flexible liquid crystal display device such as the liquid crystal device 10 of the present embodiment that can be bent.

[0045] A plurality of pixel electrodes (display electrodes) 18 are formed so as to correspond to each of a plurality of hollow bodies 20, 20... in the X direction. Each pixel electrode 18 is controlled for ON-OFF from the control unit 25 according to the display image.

[0046] As the conductive material used for the pixel electrode 18, in the transmissive liquid crystal device 10 as in the present embodiment, a visible light transmissive conductive material capable of transmitting the illumination light emitted from the backlight 19, for example, ITO, SnO2, IZO, PEDOT / PSS, etc. can be used.

[0047] In addition, in the case of a reflective liquid crystal device that uses the external light incident from the first substrate 11 as illumination light without using the backlight 19, it is preferable to use a reflective conductive material that reflects the incident external light as the pixel electrode 18. In this case, as the reflective conductive material, a metal film such as an Ag film or a Zn alloy film can be used. Further, in the case of a reflective liquid crystal device, it is preferable to form a visible light reflection layer made of a metal film or the like over the pixel electrode 18.

[0048] Also, in the embodiment shown in FIG. 2, a plurality of sub-pixels in the Y direction are configured by one hollow body 20. However, in addition to this, for example, as shown in FIG. 4, a plurality of hollow bodies 20, 20... may be arranged along the X direction and the Y direction so as to correspond one-to-one to each of the pixel electrodes (display electrodes) 18.

[0049] The color filter 14 is composed of at least a red color filter 14R, a green color filter 14G, and a blue color filter 14B as a set to form one pixel capable of full-color display. In addition, for improving the display image quality, another color filter may be further provided. Examples of the constituent material of the color filter 14 include organic pigments, dye pigments, and the like.

[0050] Note that it is preferable that a light-shielding black matrix is provided at each boundary portion (non-pixel portion) of the red color filter 14R, the green color filter 14G, and the blue color filter 14B. By providing the black matrix in this way, light leakage of illumination light from the backlight 19 and color mixing of RGB can be effectively prevented.

[0051] The backlight 19 can be used in any type of surface light source device, such as an edge light type that forms a surface light source by diffusing linearly arranged LEDs in a planar manner using a light guide plate, or a direct-lit type that forms a surface light source by using LEDs arranged in a planar manner.

[0052] The driving mode of the liquid crystal device 10 of the present embodiment having the above configuration is not particularly limited and can be appropriately selected according to the purpose. For example, as the driving mode, not only the ECB (Electrically Controlled Birefringence) mode but also the IPS (In-Plane Switching) mode and the like can be mentioned. Further, the liquid crystal layer 13 may be of a passive driving type or an active driving type using a switching element such as a TFT.

[0053] For example, as shown in FIG. 5, it is also applicable to a liquid crystal device 30 of the IPS mode in which an operating voltage of each sub-pixel is applied between comb-shaped electrodes 32 and 33 formed on a visible light-transmissive substrate 31 and arranged in a nested manner with respect to a hollow body 20 filled with liquid crystal Q.

[0054] The operation of the hollow body 20 that constitutes the liquid crystal device 10 of the present embodiment is, for example, when no voltage is applied between the common electrode 16 and the pixel electrode 18, as shown in FIG. 6(a), the major axis direction of the liquid crystal molecules is oriented in directions inclined by 45° with respect to the X-axis and the Y-axis, respectively. As a result, the illumination light from the backlight 19 is transmitted. On the other hand, when a voltage is applied between the common electrode 16 and the pixel electrode 18, as shown in FIG. 6(b), the major axis direction of the liquid crystal molecules is oriented in the Z-axis direction. As a result, the illumination light from the backlight 19 is blocked. By turning the voltage applied to each of the hollow bodies 20 that constitute such sub-pixels on and off, lighting control of the sub-pixels is performed.

[0055] According to the liquid crystal device 10 of the present embodiment configured as described above, even when the liquid crystal device 10, which is a flexible liquid crystal display device, is bent as a whole or locally, the thickness of the liquid crystal layer 13 at the bent portion does not change significantly, so the display quality such as the contrast ratio, brightness, and chromaticity of the displayed image does not deteriorate.

[0056] For example, as shown in the schematic diagram of FIG. 7, when the liquid crystal device 10 is bent, due to the difference in curvature between the first substrate 11 and the second substrate 12 sandwiching the liquid crystal layer 13, a stress is generated in the thickness direction to reduce the thickness of the liquid crystal layer 13. However, in the liquid crystal device 10 of the present embodiment, since a plurality of hollow bodies 20 filled with liquid crystal Q inside are arranged to form the liquid crystal layer 13, even when a stress is applied in the thickness direction of the liquid crystal layer 13, it is possible to suppress a change in the thickness of the liquid crystal layer 13. As a result, when the liquid crystal device 10 of the present embodiment is provided on a bent wall surface or a cylinder, the display quality such as the contrast ratio, brightness, and chromaticity can be maintained at a high level for the entire display portion including the bent portion.

[0057] Further, in the liquid crystal device 10 of the present embodiment, since a plurality of hollow bodies 20 filled with liquid crystal Q inside are arranged and these hollow bodies 20 are fixed by the fixing portion 22, even when bending is repeated, the arrangement positions of the plurality of hollow bodies 20 do not fluctuate in the liquid crystal layer 13, and the display quality can be stably maintained at a high level.

[0058] Furthermore, in the liquid crystal device 10 of the present embodiment, since a plurality of hollow bodies 20 filled with liquid crystal Q are arranged and these hollow bodies 20 are fixed by the fixing portions 22, as shown in the schematic diagram of FIG. 8, even if the liquid crystal device 10 is installed in an environment where a large stress is applied by stepping on the floor surface or the like, deformation resistance due to the pressure dispersion effect (FIG. 8(a)) and high resilience (FIG. 8(b)) can be obtained. As a result, plastic deformation of the liquid crystal layer 13 is suppressed, and stable display quality can be maintained due to the high resilience when deformed.

[0059] As described above, one embodiment of the present invention has been described. However, such an embodiment is presented as an example and is not intended to limit the scope of the invention. Such an embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and its equivalent scope.

Example

[0060] Hereinafter, a liquid crystal layer was actually manufactured and its characteristics were examined. (Confirmation of Optical Characteristics of Tubes) For the study of an optimal hollow body (hereinafter referred to as a tube), microtubes of the following three types of materials were prepared. A, silicone resin tube: inner diameter 0.1 mm, outer diameter 0.2 mm B, polymethylpentene resin tube: inner diameter 0.2 mm, outer diameter 0.4 mm C, fluororesin tube: inner diameter 0.1 mm, outer diameter 0.3 mm

[0061] Next, as a method for observing the visible light transmittance in the hollow state of these three tubes, two polarizing plates of a polarizing microscope (BX53: manufactured by Olympus Corporation) were removed, and white light was incident for observation. The results of such observations are shown in a photograph in FIG. 9. From these observation results, it was confirmed that the transmittance of visible light is low near the inner peripheral surface and the outer peripheral surface of the hollow tube.

[0062] Also, regarding the silicone resin tube, the observation results of a more magnified observation are shown in a photograph in Fig. 10(a). From these observation results, as shown in Fig. 10(b), the light transmittance decreases due to refraction on the inner peripheral surface and the outer peripheral surface of the tube. Therefore, it was confirmed that in order to increase the display luminance, it is necessary to use a material with a high visible light transmittance for the hollow body.

[0063] Hereinafter, a liquid crystal layer was actually manufactured and its characteristics were examined. (Examination of the polarization dependence of the hollow body) The polarization dependence of the tube was confirmed. Using a polarizing microscope, for the three types of tubes A to C described above, the cases where the longitudinal direction of the tube is 0 degrees and 45 degrees with respect to the polarization axis were observed between the polarizing plates of cross nicol. These observation results are shown in Fig. 11 (tube A), Fig. 12 (tube B), and Fig. 13 (tube C).

[0064] From these observation results, it was confirmed that the silicone resin tube A has no polarization dependence. Since it is desirable that the microtube used for the hollow body has no polarization dependence, among the three types of tubes made of different materials, it was confirmed that the silicone tube is particularly preferable as the hollow body. On the other hand, it was confirmed that the polymethylpentene resin tube B and the fluororesin tube C have polarization dependence. Therefore, it was confirmed that when using these as the hollow body, it is necessary to consider the polarization dependence.

[0065] (Confirmation of the alignment direction of liquid crystal molecules) In order to confirm the alignment of the liquid crystal molecules in the hollow body filled with the above-mentioned liquid crystal, verification was performed using a dichroic dye. A dichroic dye is a material composed of molecules having a strongly uniaxial light absorption axis, and absorbs light vibrating in the molecular long axis direction. When mixed with a liquid crystal, a guest - host effect occurs in which dichroic dye molecules are aligned along the alignment of the liquid crystal molecules. Therefore, by observing with a polarizing microscope with one polarizing plate removed, it can be seen that the liquid crystal molecules are aligned in the direction in which the incident polarized light is absorbed.

[0066] [Confirmation of Initial Alignment] A mixture of liquid crystal and dichroic dye was injected into and filled in the three types of tubes A to C described above, and the state of transmitted light when linearly polarized light was incident was observed. These observation results are shown in Fig. 14 (tube A), Fig. 15 (tube B), and Fig. 16 (tube C).

[0067] In Figs. 14(a) and 15(a) where the longitudinal direction of the tube is equal to the direction of incident polarized light, it was confirmed that visible light is transmitted near the inner peripheral surface and absorbed at the center of the hollow part. On the other hand, in Figs. 14(b) and 15(b) where the longitudinal direction of the tube is orthogonal to the direction of incident polarized light, it was confirmed that visible light is absorbed near the inner peripheral surface and transmitted at the center of the hollow part. From these observation results, in the A, silicon resin tube and the B, polymethylpentene resin tube, as shown in Fig. 3(b), it was confirmed that the liquid crystal is aligned in the radial direction near the inner peripheral surface and in the longitudinal direction at the center of the hollow part.

[0068] On the other hand, in the C, fluororesin tube, it was confirmed that visible light is absorbed in the state where the longitudinal direction is equal to the direction of incident polarized light (Fig. 16(a)) and transmitted in the state where the longitudinal direction is orthogonal to the direction of incident polarized light (Fig. 16(b)). From this, it was found that in the fluororesin tube, as shown in Fig. 3(a), the liquid crystal molecules are aligned in the longitudinal direction of the tube.

[0069] From these results, it is considered that the alignment of the liquid crystal molecules in the tube is affected not only by the shape of the tube based on the continuous elastic body theory but also by the influence from the wall surface according to the resin material constituting the tube.

[0070] [Confirmation of Flow Alignment] To confirm that the above-mentioned initial orientation is not due to the flow orientation of the liquid crystal, a tube filled with liquid crystal was heated to 140 °C to make the liquid crystal isotropic, allowed to cool for a while until it returned to the liquid crystal phase, and then observed with a polarizing microscope. The results of such observations are shown in FIGS. 17 (tube C) and 18 (tube A). From the observation results in FIGS. 17 and 18, it was confirmed that both the long-axis orientation and the radial orientation returned to the original orientation. From this result, it was found that the liquid crystal molecular orientation of the hollow body is not due to the flow orientation, but is oriented by the continuous elastic body theory and the influence from the wall surface of the tube.

[0071] [Confirmation of the Influence of the Tube Diameter on the Orientation Direction] As the long-axis orientation, fluororesin tubes of the following three dimensions were prepared and observed using a polarizing microscope. (C-a) Inner diameter 0.11 mm, outer diameter 0.3 mm (C-b) Inner diameter 0.33 mm, outer diameter 0.5 mm (C-c) Inner diameter 0.55 mm, outer diameter 0.7 mm The results of such observations are shown in FIGS. 19(a): (tube C-a), FIGS. 19(b): (tube C-b), and FIGS. 19(c): (tube C-c).

[0072] From the results shown in FIG. 19, in all of the fluororesin tubes of the three dimensions, it was confirmed that visible light was absorbed when the longitudinal direction of the tube was equal to the direction of incident polarized light, and visible light was transmitted when the longitudinal direction of the tube was orthogonal to the direction of incident polarized light. From this, it was found that the fluororesin tubes exhibit long-axis orientation regardless of the inner diameter dimension of the tube.

[0073] As the radial orientation, silicon resin tubes of the following three dimensions were prepared and observed using a polarizing microscope. (A-a) Inner diameter 0.11 mm, outer diameter 0.2 mm (A-b) Inner diameter 0.33 mm, outer diameter 0.4 mm (A-c) Inner diameter 0.55 mm, outer diameter 1.0 mm These observation results are shown in Fig. 20(a): (Tube of A-a), Fig. 20(b): (Tube of A-b), and Fig. 20(c): (Tube of A-c).

[0074] From the results shown in Fig. 20, in all three types of silicon resin tubes, when the longitudinal direction of the tube is equal to the direction of the incident polarized light, light is transmitted near the inner peripheral surface of the tube and absorbed at the center of the hollow part. When the longitudinal direction of the tube is perpendicular to the direction of the incident polarized light, it was confirmed that light is absorbed near the inner peripheral surface of the tube and transmitted at the center of the hollow part. From this, it was found that the silicon resin tube exhibits radial orientation regardless of the inner diameter dimension of the tube.

[0075] According to the results shown in Figs. 19 and 20 above, in both the long-axis orientation and the radial orientation, it was confirmed that the liquid crystal (liquid crystal molecules) is oriented up to the central part of the tube regardless of the inner diameter of the tube. From this, compared with a conventional general liquid crystal device in which liquid crystal is enclosed between two substrates, the liquid crystal device of this embodiment has a shape in which the tube surrounding the liquid crystal on all sides has a strong orientation control force, and it was found that the orientation control of the liquid crystal molecules is easy. Furthermore, when an electric field perpendicular to the substrate surface was applied to the liquid crystal (nematic liquid crystal) whose molecules are oriented in the tube, it was found by observation with a polarizing microscope that the molecular orientation of the liquid crystal changes. Thereby, it was confirmed that the display operation (light modulation function) is possible with the configuration of the present invention.

[0076] [Confirmation of Durability of Hollow Body] To confirm the durability of the tube, the alignment of liquid crystal molecules before and after pressure application was observed. First, a mixture of liquid crystal and dichroic dye was injected into the tube and filled to form a hollow body, and the state of transmitted light when linearly polarized light was incident on the hollow body before and after pressure application was observed with a polarizing microscope. The observation method is shown in Fig. 21, and the conditions of the applied pressure are shown in Table 1.

[0077]

Table 1

[0078] As an observation result when pressure is applied in the case of longitudinal orientation using a fluororesin tube, the case where the longitudinal direction of the tube is equal to the direction of incident polarized light is shown in Fig. 22(a), and the case where the longitudinal direction of the tube is orthogonal to the direction of incident polarized light is shown in Fig. 22(b).

[0079] According to the observation results shown in Fig. 22, it was confirmed that in the longitudinal orientation, the orientation of liquid crystal molecules did not change before and after the application of pressure. Also, when visually observed, it was confirmed that the tube was not crushed during the application of pressure. From these results, it was confirmed that the hollow body using the fluororesin tube has deformation resistance when pressure is applied from the outside and can be used as a hollow body with high durability. It was found that it has sufficient resistance even when assuming pressure when a person rides on it.

[0080] As an observation result when pressure is applied in the case of radial orientation using a silicone resin tube, the case where the longitudinal direction of the tube is equal to the direction of incident polarized light is shown in Fig. 23(a), and the case where the longitudinal direction of the tube is orthogonal to the direction of incident polarized light is shown in Fig. 23(b).

[0081] According to the observation results shown in Fig. 23, it was confirmed that in the radial orientation, the orientation of liquid crystal molecules did not change before and after the application of pressure. Also, when visually observed, the tube was slightly crushed during the application of pressure, but it was confirmed that it restored to its original shape after the removal of pressure and had a restoring force. From these results, it was confirmed that the hollow body using the silicone resin tube has a restoring force when pressure is applied from the outside and can be used as a hollow body with high durability.

Industrial Applicability

[0082] The present invention contributes to improving the display quality when a bendable liquid crystal device, for example, a flexible liquid crystal display device is bent, and preventing deterioration of the display quality and damage to the liquid crystal layer due to the application of stress. Therefore, it has industrial applicability.

Explanation of Reference Numerals

[0083] 10…Liquid crystal device 11…First substrate 12…Second substrate 13…Liquid crystal layer 14…Color filter 15…First polarizer 16…Common electrode 17…Second polarizer 18…Pixel electrode 19…Backlight 20…Hollow body (microtube) 22…Fixing part Q…Liquid crystal

Claims

1. A first substrate having flexibility and made of a visible light transmissive material, a second substrate having flexibility, a liquid crystal layer disposed between the first substrate and the second substrate, and at least a hollow body made of a visible light transmissive material and filled with liquid crystal therein. The liquid crystal device is characterized in that the liquid crystal layer is formed by arranging a plurality of the hollow bodies.

2. The liquid crystal device according to claim 1, wherein the hollow body is cylindrical or polygonal cylindrical.

3. The liquid crystal device according to claim 1 or 2, wherein an alignment film for aligning the direction of the long axis of liquid crystal molecules with order is disposed on the inner peripheral surface of the hollow body.

4. The liquid crystal device according to claim 1 or 2, wherein a common electrode made of a visible light transmissive conductive material is disposed in contact with one surface of the liquid crystal layer, and a plurality of pixel electrodes corresponding to the respective hollow bodies are disposed in contact with the other surface or the one surface of the liquid crystal layer.

5. The liquid crystal device according to claim 1 or 2, wherein a first polarizing plate is disposed between the first substrate and the liquid crystal layer, and a second polarizing plate having a polarization direction different from that of the first polarizing plate is disposed between the second substrate and the liquid crystal layer.

6. The liquid crystal device according to claim 1 or 2, wherein fixing portions for fixing the respective hollow bodies are formed between the hollow bodies adjacent to each other in the liquid crystal layer.

7. The liquid crystal device according to claim 6, wherein the fixing portion is made of a resin material.

8. The liquid crystal device according to claim 1 or 2, wherein a color filter is disposed between the first substrate and the liquid crystal layer or between the second substrate and the liquid crystal layer.

9. The liquid crystal device according to claim 1 or 2, wherein the second substrate is made of a visible light transmissive material, and a backlight for irradiating illumination light toward the first substrate is disposed on the outer surface side of the second substrate.

10. The liquid crystal device according to claim 1 or 2, wherein a visible light reflecting layer is formed between the second substrate and the liquid crystal layer.

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