Liquid crystal element, method for manufacturing liquid crystal elements

Abstract

To provide a manufacturing method of easily manufacturing a liquid crystal element without requiring specific orientation films.SOLUTION: The manufacturing method of a liquid crystal element includes: arranging a liquid crystal material between a first substrate and a second substrate to form a liquid crystal layer; and irradiating the liquid crystal layer with light from a direction obliquely intersecting with the other surface facing one surface of the first substrate or of the second substrate via the first substrate or the second substrate to form on a surface of a first insulator film facing the liquid crystal layer a first polymer layer including polymer arranged in a direction obliquely intersecting with one surface of the first substrate and to form on a surface of a second insulator film facing the liquid crystal layer a second polymer layer including polymer arranged in a direction obliquely intersecting with one surface of the second substrate. The liquid crystal material contains monomer which is optically polymerizable and a trans-structure having double bond at a center part thereof.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to a liquid crystal element and a method for manufacturing the liquid crystal element.

Background Art

[0002] Japanese Unexamined Patent Application Publication No. 2019-128383 (Patent Document 1) describes a liquid crystal display device having a pair of substrates, a liquid crystal layer disposed between the pair of substrates, an alignment film disposed on the surface of at least one of the pair of substrates on the liquid crystal layer side, and a polymer layer disposed between the liquid crystal layer and each alignment film. In this liquid crystal display device, the liquid crystal layer contains a liquid crystal compound oriented in a predetermined direction when no voltage is applied, each alignment film contains a first polymer having at least one of a polyamic acid structure and a polyimide structure in the main chain, the first polymer has a functional group that functions as a polymerization initiator, and each polymer layer contains a second polymer obtained by polymerizing at least one monomer having a chalcone group.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] One of the objects of a specific aspect according to the present disclosure is to provide a method for manufacturing a liquid crystal element that does not require a special alignment film and is easy to manufacture. Another object of a specific aspect according to the present disclosure is to provide a liquid crystal element obtained by the above manufacturing method.

Means for Solving the Problems

[0005] [1] A method for manufacturing a liquid crystal element according to one aspect of the present disclosure includes (a) forming a first insulating film on one side of a first substrate, (b) forming a second insulating film on one side of a second substrate, (c) forming a liquid crystal layer between the respective surfaces of the first substrate and the second substrate, and (d) irradiating the liquid crystal layer with light from a direction oblique to the other surface of at least one of the first substrate and the second substrate that faces the surface facing the liquid crystal layer, thereby forming a first polymer layer having polymers arranged in a direction inclined with respect to one side of the first substrate on the surface of the first insulating film facing the liquid crystal layer, and forming a second polymer layer having polymers arranged in a direction inclined with respect to one side of the second substrate on the surface of the second insulating film facing the liquid crystal layer, wherein the liquid crystal material used in forming the liquid crystal layer in (c) contains a monomer that is polymerizable by light and is a trans isomer having a double bond in its center. [2] A liquid crystal element according to one aspect of the present disclosure includes: (a) a first substrate having a first insulating film on one side; (b) a second substrate having a second insulating film on one side, disposed with a gap between it and the first substrate so that the first insulating film and the second insulating film face each other; (c) a liquid crystal layer disposed in the gap between the first substrate and the second substrate; (d) a first polymer layer disposed on the surface of the first insulating film facing the liquid crystal layer and having a polymer arranged in a direction inclined with respect to one side of the first substrate; and (e) a second polymer layer disposed on the surface of the second insulating film facing the liquid crystal layer and having a polymer arranged in a direction inclined with respect to one side of the second substrate. Furthermore, the first insulating film and the second insulating film are inorganic insulating films formed using silica or titania, or vertically aligned films having an inorganic main chain and side chains. It is a liquid crystal element.

[0006] According to the above configuration, a method for manufacturing liquid crystal elements that do not require a special alignment film and are easy to manufacture is provided. Furthermore, a liquid crystal element obtained by this manufacturing method is also provided. [Brief explanation of the drawing]

[0007] [Figure 1]Figure 1(A) is a schematic cross-sectional view illustrating the configuration of the liquid crystal element of the first embodiment. Figure 1(B) is a schematic diagram showing the polymers of the first polymer layer or the second polymer layer. [Figure 2] Figures 2(A) to 2(F) are diagrams illustrating the manufacturing method of the liquid crystal element according to the first embodiment. [Figure 3] Figures 3(A) to 3(C) are diagrams illustrating the manufacturing method of the liquid crystal element according to the first embodiment. [Figure 4] Figures 4(A) and 4(B) illustrate modified examples of the process of irradiating the liquid crystal layer with light. [Figure 5] Figure 5(A) is a schematic cross-sectional view illustrating the configuration of the liquid crystal element in the second embodiment. Figure 5(B) is a schematic cross-sectional view illustrating the configuration of the liquid crystal element in the third embodiment. [Figure 6] Figure 6 shows the relationship between the irradiation angle and the pre-tilt angle during light irradiation in the liquid crystal element of Example 1, which was fabricated using a monomer containing a chalcone group. [Figure 7] Figure 7 shows the relationship between the irradiation angle and the pre-tilt angle when light is irradiated into the liquid crystal element of Example 2. [Modes for carrying out the invention]

[0008] Figure 1(A) is a schematic cross-sectional view illustrating the configuration of a liquid crystal element according to the first embodiment. The illustrated liquid crystal element 1 comprises a first substrate 11 and a second substrate 12 arranged opposite each other, a plurality of pixel electrodes 13, a counter electrode 14, a first insulating film 15, a second insulating film 16, a first polymer layer 17, a second polymer layer 18, a liquid crystal layer 19, and a sealing material 20.

[0009] The first substrate 11 and the second substrate 12 are, for example, transparent substrates that are rectangular in shape when viewed from above, and are arranged with one side facing the other. For the first substrate 11 and the second substrate 12, for example, glass substrates or plastic substrates can be used. Spherical spacers (not shown), for example, made of a resin film, are dispersed between the first substrate 11 and the second substrate 12, and these spherical spacers maintain the gap between the substrates at a desired size (for example, about a few micrometers).

[0010] Alternatively, instead of spherical spacers, columnar bodies made of resin or the like may be provided on the first substrate 11 side or the second substrate 12 side and used as spacers. Although not shown in the figures, polarizing plates or polarizing elements can be placed on the outside of each of the first substrate 11 and the second substrate 12 (the side not facing the liquid crystal layer 19), and optical compensating plates such as phase difference plates can be placed between each polarizing plate, etc. and the first substrate 11 or the second substrate 12.

[0011] Multiple pixel electrodes 13 are provided on one side of the first substrate 11. These pixel electrodes 13 are formed by appropriately patterning a transparent conductive film, such as indium tin oxide (ITO). In this embodiment, a pixel portion is formed in the area where each pixel electrode 13 and the opposing electrode 14 face each other.

[0012] The counter electrode 14 is provided on one side of the second substrate 12. This counter electrode 14 is integrally provided so as to face each pixel electrode 13 of the first substrate 11. The counter electrode 14 is constructed by appropriately patterning a transparent conductive film, such as indium tin oxide (ITO).

[0013] The first insulating film 15 is provided to cover each pixel electrode 13 on one side of the first substrate 11. The second insulating film 16 is provided to cover the counter electrode 14 on one side of the second substrate 12. The first insulating film 15 and the second insulating film 16 are arranged with a gap therebetween in a state of facing each other. The first insulating film 15 and the second insulating film 16 are preferably inorganic insulating films formed using, for example, silica or titania, and for example, a titanosiloxane-based inorganic insulating film can be used. No alignment treatment such as rubbing treatment is performed on each of the first insulating film 15 and the second insulating film 16.

[0014] The first polymer layer 17 is arranged to contact the liquid crystal layer 19 on the surface of the first insulating film 15 facing the liquid crystal layer 19. Further, the second polymer layer 18 is arranged to contact the liquid crystal layer 19 on the surface of the second insulating film 16 facing the liquid crystal layer 19. The first polymer layer 17 has a plurality of polymers (polymers) arranged in a direction inclined with respect to one surface of the first substrate 11. Similarly, the second polymer layer 18 has a plurality of polymers (polymers) arranged in a direction inclined with respect to one surface of the second substrate 12.

[0015] The liquid crystal layer 19 is provided in the gap between the first substrate 11 and the second substrate 12. The liquid crystal layer 19 is configured using, for example, a nematic liquid crystal material having fluidity. The liquid crystal layer 19 is configured using, for example, a liquid crystal material having negative dielectric anisotropy. The layer thickness of the liquid crystal layer 19 can be, for example, about 4 μm. The liquid crystal layer 19 is aligned under the alignment regulating force of the first polymer layer 17 and the second polymer layer 18, and has a pretilt angle of, for example, about 85° to 89.9° and is uniformly aligned when no voltage is applied (including when a voltage below the threshold is applied).

[0016] The sealing material 20 is provided between the first substrate 11 and the second substrate 12 so as to surround the liquid crystal layer 19 and seals the liquid crystal layer 19. As shown in the figure, in this embodiment, the sealing material 20 is provided so as to surround the outside of the region where the first insulating film 15, the second insulating film 16, the first polymer layer 17, and the second polymer layer 18 are provided.

[0017] FIG. 1(B) is a diagram schematically showing the polymer of the first polymer layer or the second polymer layer. Each polymer 21 is disposed obliquely on one surface 22 of each of the first insulating film 15 and the second insulating film 16. In other words, each polymer 21 is disposed in a direction inclined with respect to one surface of the first substrate 11 and the second substrate 12. Each polymer 21 in the first embodiment is obtained by polymerizing a monomer of a trans form having a double bond at the central portion of the molecule by light irradiation (ultraviolet irradiation in this embodiment), and has two or more polymerization sites. Further, it is also preferable that each polymer 21 is obtained by polymerizing a monomer containing a chalcone group.

[0018] In the illustrated example, each polymer 21 is uniformly arranged in the upper left direction in the figure. The "uniform" here does not mean that each polymer 21 is strictly in the same direction, but rather approximately in the same direction. These polymers 21 exert an alignment regulating force on the liquid crystal layer 19, and the liquid crystal molecules of the liquid crystal layer 19 can be uniformly aligned. Here, only the polymer 21 is illustrated, but monomers may remain on one surface 22 of each of the first insulating film 15 and the second insulating film 16.

[0019] As an example, the mechanism of the manifestation of the alignment regulating force when a monomer containing a chalcone group is used is presumed as follows. The molecule (RM molecule) of the monomer containing a chalcone group has three reaction portions, and the inner olefin (double bond at the center of the molecule) is less likely to be photopolymerized than the reaction portions at both ends. The double bond at the center of the molecule can take a cis-trans form, but the trans form is dominant. In the case of the trans form, it is considered that the direction of the molecule is slightly inclined by the double bond at the center of the RM molecule. Before light irradiation, the liquid crystal molecules of the liquid crystal layer 19 are almost completely vertically aligned, and the RM molecules are also in the same direction but in the trans form, so each molecule is slightly inclined. When light irradiation is performed on the liquid crystal layer 19 from an oblique direction, the inner olefin in the portion that is easily exposed to ultraviolet light is polymerized, and since the remaining RM molecules in the trans form are inclined, it is considered that they have a slight effect of aligning the liquid crystal molecules.

[0020] Figures 2(A) to 2(F) and 3(A) to 3(C) are diagrams illustrating the manufacturing method of a liquid crystal element according to the first embodiment. Note that the order of each step can be changed or performed in parallel, as long as no contradictions or inconsistencies arise, and other steps not shown or described (e.g., a cleaning step) may be added as appropriate.

[0021] First, a first substrate 11 having each pixel electrode 13 on one surface 11a is prepared (Figure 2(A)), and a second substrate 12 having a counter electrode 14 on one surface 12a is prepared (Figure 2(B)). As described above, each pixel electrode 13 and counter electrode 14 are obtained, for example, by patterning an ITO film deposited on one surface of the first substrate 11 and the second substrate 12 using photolithography or the like.

[0022] Next, a first insulating film 15 is formed on one side 11a of the first substrate 11 so as to cover each pixel electrode 13 (Figure 2(C)). Similarly, a second insulating film 16 is formed on one side 12a of the second substrate 12 so as to cover the counter electrode 14 (Figure 2(D)).

[0023] The first insulating film 15 and the second insulating film 16 are preferably inorganic insulating films formed using, for example, silica or titania, and a titanosiloxane-based inorganic insulating film can be used. There are no particular limitations on the film formation method for the first insulating film 15 and the second insulating film 16, and sputtering, evaporation, CVD, printing, etc., can be used as appropriate. In particular, forming the first insulating film 15 and the second insulating film 16 using insulating films to which printing methods can be applied, such as a titanosiloxane-based inorganic insulating film, is preferable in terms of simplifying the process.

[0024] Next, the sealing material 20 is applied to one side of the first substrate 11 or the second substrate 12 (Figure 2(E)). In the illustrated example, the sealing material 20 is applied to one side 12a of the second substrate 12, but it may also be applied to one side 11a of the first substrate 11. In this embodiment, the sealing material 20 made of a photocurable resin is used. In addition, spherical spacers for gap control are scattered on one side of the substrate (first substrate 11 in this embodiment) on the side where the sealing material 20 is not applied.

[0025] Next, with the first insulating film 15 and the second insulating film 16 facing each other, the first substrate 11 and the second substrate 12 are bonded together (Figure 2(F)). A gap is provided between the first substrate 11 and the second substrate 12 by spherical spacers.

[0026] Next, a liquid crystal layer 19 is formed by injecting liquid crystal material into the gap between the first substrate 11 and the second substrate 12 by vacuum injection through an injection port (a portion of the sealing material 20 that is partially opened) (Figure 3(A)). In this embodiment, a liquid crystal material is used that contains a monomer that can be polymerized by light (especially ultraviolet light), and the monomer is a trans isomer having a double bond in its center. The monomer contained in the liquid crystal material is preferably a monomer having two or more polymerization sites, and is also preferably a monomer containing a chalcone group.

[0027] Furthermore, the ODF (One Drop Fill) method may be used when injecting the liquid crystal material. In this case, after forming the encapsulant 20, and before bonding the first substrate 11 and the second substrate 12, the liquid crystal material is dropped (placed) into the area surrounded by the encapsulant 20, and then the first substrate 11 and the second substrate 12 are bonded together.

[0028] Next, light is irradiated onto the liquid crystal layer 19 via the first substrate 11 or the second substrate 12 from a direction oblique to the other surface facing one side of the first substrate 11 or the second substrate 12 (Figure 3(B)). In this step, it is preferable from a manufacturing standpoint to perform the step without applying voltage to the liquid crystal layer 19. However, this does not preclude applying voltage to the liquid crystal layer 19 during light irradiation. If voltage is applied, it is thought that the pre-tilt angle can be actively controlled by the magnitude of the voltage by irradiating the liquid crystal layer 19 from an oblique direction as described above for a certain period of time (e.g., 30 seconds to 2 minutes) from the start of light irradiation without applying voltage to the liquid crystal layer 19, and then applying voltage to the liquid crystal layer 19. There are no particular limitations on the direction of light irradiation when voltage is applied; it may continue to be oblique, or it may be in another direction (e.g., the front direction).

[0029] In this embodiment, since a photocurable substance (such as a resin) is used as the encapsulant 20, the encapsulant 20 can be cured simultaneously in the process shown in Figure 3(B). This eliminates the need to add new steps for forming the first polymer layer 15 and the second polymer layer 16 to the conventional manufacturing process, thus simplifying the manufacturing method. Although this description describes the case where a photocurable resin is used as the encapsulant, a thermosetting resin may also be used. When vacuum injection is performed, a photocurable resin is preferred as the end seal material (injection port sealant) for sealing the injection port, and the end seal material can be cured simultaneously in the process shown in Figure 3(B). This eliminates the need to add new steps for forming the first polymer layer 15 and the second polymer layer 16 to the conventional manufacturing process, thus simplifying the manufacturing method.

[0030] In this embodiment, ultraviolet light is irradiated from a direction oblique to the other surface 12b of the second substrate 12 that is opposite to one surface 12a. For example, if the normal a of the second substrate 12 to the other surface 11 is taken as a reference, the ultraviolet light (UV) is irradiated from a direction oblique to the normal a at an angle θ. This angle θ can be set as appropriate, for example, between 30° and 60°. In addition, light irradiation may be performed from a direction oblique to the other surface of the first substrate 11, or light irradiation may be performed from a direction oblique to the other surface of both the other surface of the first substrate 11 and the other surface of the second substrate.

[0031] The monomers contained in the liquid crystal layer 19 polymerize due to the light irradiation described above. As a result, a first polymer layer 15 is formed on the first substrate 11 side and a second polymer layer 16 is formed on the second substrate 12 side (Figure 3(C)). The first polymer layer 15 and the second polymer layer 16 each have polymers or monomers arranged in a direction inclined with respect to one surface of the first substrate 11 and the second substrate, respectively, as shown in Figure 1(B) described above. The first polymer layer 15 and the second polymer layer 16 impart an orientation restricting force to the liquid crystal layer 19, causing the liquid crystal layer 19 to be uniformly oriented (Figure 3(C)). Thus, the liquid crystal element 1 is completed.

[0032] Figures 4(A) and 4(B) illustrate modified examples of the process of irradiating the liquid crystal layer with light. In this process, as shown in Figure 4(A), a mask 30 that partially shields the left-hand region of the liquid crystal layer 19 is placed on the other side of the second substrate 12, and light irradiation is performed through the mask 30. Then, as shown in Figure 4(B), the placement of the mask 30 is changed to partially shield the right-hand region of the liquid crystal layer 19, and light irradiation is performed through the mask 30.

[0033] In the illustrated example, in the process shown in Figure 4(A), light irradiation is performed from a direction tilted clockwise by an angle θ1 from the normal to the second substrate 12, and in the process shown in Figure 4(B), light irradiation is performed from a direction tilted counterclockwise by an angle θ2 from the normal to the second substrate 12. Note that the settings of angles θ1 and θ2 are illustrative, and angles θ1 and θ2 may be set so that the angles are different in the same direction (clockwise or counterclockwise). For example, in each process, the light irradiation direction can be set clockwise from the normal to the second substrate 12, with angles θ1 = 30° and θ2 = 45°. In this way, the pre-tilt angle of the liquid crystal layer 19 can be set to different sizes and directions corresponding to regions with different light irradiation directions. Also, the number of times the mask 30 arrangement is changed is not limited to the two times described above, but may be increased.

[0034] Figure 5(A) is a schematic cross-sectional view illustrating the configuration of the liquid crystal element of the second embodiment. The liquid crystal element 1a of the second embodiment shown in Figure 5(A) differs from the liquid crystal element 1 of the first embodiment described above in that the first insulating film 15 and the second insulating film 16 are each made of vertically aligned films, namely the first insulating film 15a and the second insulating film 16a, respectively, but the other configurations are the same. The first insulating film 15a and the second insulating film 16a are both vertically aligned films with an inorganic main chain and side chains. Furthermore, no alignment treatment such as rubbing is performed on either the first insulating film 15a or the second insulating film 16a. The first polymer layer 17 is placed between the first insulating film 15a and the liquid crystal layer 19, and the second polymer layer 18 is placed between the second insulating film 16a and the liquid crystal layer 19. The liquid crystal element 1a of this second embodiment can also obtain the same effects as the liquid crystal element 1 of the first embodiment described above.

[0035] Figure 5(B) is a schematic cross-sectional view illustrating the configuration of the liquid crystal element of the third embodiment. The liquid crystal element 1b of the third embodiment shown in Figure 5(B) differs from the liquid crystal element 1 of the first embodiment described above in that the first insulating film 15 and the second insulating film 16 are omitted, but the other configurations are the same. In this liquid crystal element 1b, the first polymer layer 17 is arranged between the first substrate 11 and each pixel electrode 13 and the liquid crystal layer 19, and the second polymer layer 18 is arranged between the second substrate 12 and the counter electrode 14 and the liquid crystal layer 19. b This also provides the same effect as the liquid crystal element 1 of the first embodiment described above.

[0036] (Example 1) A liquid crystal element of an embodiment having the configuration of the liquid crystal element 1 of the first embodiment was fabricated. Glass substrates were used as the first substrate 11 and the second substrate 12, and titanosiloxane-based inorganic insulating films were used as the first insulating film 15 and the second insulating film 16, respectively. No orientation treatment such as rubbing treatment was performed on the first insulating film 15 and the second insulating film 16. The thickness of the liquid crystal layer 19 was approximately 4 μm. A nematic liquid crystal material with negative dielectric anisotropy was used as the liquid crystal material. Monomers containing chalcone groups or monomers without chalcone groups were added to the liquid crystal material in amounts of 0.1 wt%, 0.2 wt%, 0.5 wt%, or 1.0 wt% to form the first polymer layer 17 and the second polymer layer 18. The amount added can be adjusted, for example, from 0.1 wt% to 5 wt%. Monomers containing chalcone groups are trans isomers that have a double bond in the central part of the molecule and have two or more polymerization sites. In the light irradiation process for the liquid crystal layer 19, ultraviolet light was irradiated from a direction that formed a 45° angle relative to the second substrate 12 (see Figure 3(B)). The irradiation dose of ultraviolet light was 20 J / cm². 2 (=28mW / cm 2 The test was performed for 12 minutes. A self-aligning agent may be added to the liquid crystal material in an amount of approximately 0.1 wt% to 10 wt%.

[0037] In a comparison of the appearance of liquid crystal elements fabricated using monomers containing chalcone groups and liquid crystal elements fabricated using monomers that do not contain chalcone groups, the former tended to exhibit superior uniformity of the orientation of the liquid crystal layer 19.

[0038] Figure 6 shows the relationship between the irradiation angle and the pretilt angle in a liquid crystal element of Example 1, which was fabricated using a monomer containing a chalcone group. Four patterns were set for the amount of monomer added: 0.1 wt%, 0.2 wt%, 0.5 wt%, and 1.0 wt%. Three patterns were set for the irradiation angle θ (see Figure 3(B)): 30°, 45°, and 60°. When the amount of monomer added was 0.1 wt% and 0.2 wt%, the pretilt angle was 89.9° to 90°, with little dependence on the irradiation angle during light irradiation, and even at an irradiation angle of 60°, the pretilt angle was approximately 89.9°. It is considered beneficial to secure a large margin for error in the irradiation angle during light irradiation when it is desired to obtain a liquid crystal layer 19 with a pretilt angle of 90° (vertical orientation) or a pretilt angle of approximately 89.9° (approximately vertical orientation).

[0039] On the other hand, it was found that the dependence of the pre-tilt angle on the irradiation angle during light irradiation was more clearly observed when the monomer addition amount was 0.5 wt% and 1.0 wt%. Specifically, the pre-tilt angle was obtained in the range of 88.0° to 89.7°. Furthermore, a tendency was observed for the pre-tilt angle to decrease as the irradiation angle increased. It is considered beneficial that the pre-tilt angle can be controlled by the irradiation angle when it is desired to actively impart a pre-tilt angle to the liquid crystal layer 19.

[0040] (Example 2) A liquid crystal element of an embodiment having the configuration of the liquid crystal element 1a of the second embodiment was fabricated. Glass substrates were used as the first substrate 11 and the second substrate 12, and vertically aligned films with an inorganic main chain and side chains were used as the first insulating film 15a and the second insulating film 16a, respectively. No orientation treatment such as rubbing treatment was performed on the first insulating film 15a and the second insulating film 16a. The thickness of the liquid crystal layer 19 was approximately 4 μm. A nematic liquid crystal material with negative dielectric anisotropy was used as the liquid crystal material. A monomer containing a chalcone group was added to the liquid crystal material at a concentration of 0.3 wt% as a monomer for forming the first polymer layer 17 and the second polymer layer 18. The monomer containing a chalcone group is a trans isomer having a double bond in the center of the molecule and has two or more polymerization sites. In the light irradiation process for the liquid crystal layer 19, the irradiation angle θ (see Figure 3(B)) was set to three patterns: 30°, 45°, and 60°. The ultraviolet light irradiation dose was 20 J / cm 2 (=28mW / cm 2 The test was performed for 12 minutes. A self-aligning agent may be added to the liquid crystal material in an amount of approximately 0.1 wt% to 10 wt%.

[0041] Figure 7 shows the relationship between the irradiation angle and the pre-tilt angle during light irradiation in the liquid crystal element of Example 2. It was found that the pre-tilt angle has a dependence on the irradiation angle during light irradiation. Specifically, the pre-tilt angle was obtained in the range of 89.4° to 88.9°. Furthermore, a tendency was observed for the pre-tilt angle to decrease as the irradiation angle increased.

[0042] (Example 3) A liquid crystal element was fabricated under the same conditions as in Example 1 described above, and multiple light irradiations were performed using a mask during the light irradiation process. Specifically, in the light irradiation process (see Figures 4(A) and 4(B)), light irradiation was performed on the area not shielded by the mask 30 from a direction tilted 45° clockwise from the normal to the second substrate 12. Then, the position of the mask 30 was changed, and light irradiation was performed on the area not shielded by the changed mask 30 from a direction tilted 30° counterclockwise from the normal to the second substrate 12.

[0043] When the pre-tilt angle of the obtained liquid crystal elements was measured, the pre-tilt angle was 88.4° in the region where the illumination angle during light irradiation was 45°, and it was also 88.4° in the region where the illumination angle during light irradiation was 30°. Furthermore, the best viewing direction (the direction in which the pre-tilt angle is applied) in the region with an illumination angle of 45° and the region with an illumination angle of 30° were 180° opposite to each other. In other words, multi-domain orientation was obtained.

[0044] According to the embodiments and examples described above, a method for manufacturing liquid crystal elements that do not require a special alignment film and are easy to manufacture is provided. Furthermore, a liquid crystal element obtained by this manufacturing method is also provided.

[0045] Furthermore, this disclosure is not limited to the embodiments described above, and can be implemented in various modified forms within the scope of the gist of this disclosure. For example, the numerical conditions described in each of the embodiments described above are merely examples and are not limited to those numerical conditions.

[0046] This disclosure has the following features:

[0047] (Note 1) (a) Forming a first insulating film on one side of the first substrate, (b) Forming a second insulating film on one side of the second substrate, (c) Forming a liquid crystal layer between each of the one surfaces of the first substrate and the second substrate, (d) By irradiating the liquid crystal layer with light from a direction oblique to the other surface of at least one of the first substrate and the second substrate that is opposite to the one surface, a first polymer layer having polymers arranged in a direction inclined with respect to one surface of the first substrate is formed on the surface of the first insulating film that is opposite to the liquid crystal layer, and a second polymer layer having polymers arranged in a direction inclined with respect to one surface of the second substrate is formed on the surface of the second insulating film that is opposite to the liquid crystal layer. Includes, In (c) above, the liquid crystal material used to form the liquid crystal layer contains a monomer that is polymerizable by light and is a trans isomer having a double bond in its central part. A method for manufacturing liquid crystal elements. (Note 2) The oblique direction during light irradiation in (d) above is a direction that forms an angle of 30° or more and 60° or less with respect to the other surface of either the first substrate or the second substrate. The method for manufacturing liquid crystal elements as described in Appendix 1. (Note 3) The monomer is a monomer that can be polymerized by ultraviolet light. A method for manufacturing a liquid crystal element as described in Appendix 1 or 2. (Note 4) The monomer has two or more polymerization sites. A method for manufacturing a liquid crystal element as described in any one of the appendices 1 to 3. (Note 5) The monomer is a monomer containing a chalcone group. A method for manufacturing a liquid crystal element as described in any one of the appendices 1 to 4. (Note 6) The first insulating film and the second insulating film are inorganic insulating films formed using silica or titania. A method for manufacturing a liquid crystal element as described in any one of the appendices 1 to 5. (Note 7) The first insulating film and the second insulating film are vertically aligned films having inorganic main chains and side chains, and are vertically aligned films that have not undergone any orientation treatment. A method for manufacturing a liquid crystal element as described in any one of the appendices 1 to 5. (Note 8) The aforementioned ( d ) includes placing a mask that partially shields the liquid crystal layer from light on the other side of the first or second substrate and performing the light irradiation through the mask, wherein the light irradiation is performed each time the placement of the mask is changed. A method for manufacturing a liquid crystal element as described in any one of the appendices 1 to 7. (Note 9) A first substrate having a first insulating film on one side, A second substrate having a second insulating film on one side, and arranged with a gap between it and the first substrate, with the first insulating film and the second insulating film facing each other. A liquid crystal layer disposed in the gap between the first substrate and the second substrate, A first polymer layer having a polymer arranged on the surface of the first insulating film facing the liquid crystal layer and in a direction inclined with respect to one surface of the first substrate, A second polymer layer having a polymer arranged on the surface of the second insulating film facing the liquid crystal layer and in a direction inclined with respect to one surface of the second substrate, Liquid crystal elements, including those mentioned above. (Note 10) The first insulating film and the second insulating film are inorganic insulating films formed using silica or titania. The liquid crystal element described in Appendix 9. (Note 11) The liquid crystal layer is uniformly oriented under the orientation-regulating force of the first polymer layer and / or the second polymer layer. The liquid crystal element described in Appendix 9 or 10. (Note 12) The polymer in each of the first and second polymer layers is formed by polymerization of trans monomers having a double bond in the central part. A liquid crystal element as described in any one of the appendices 9 to 11. [Explanation of Symbols]

[0048] 11: First substrate, 12: Second substrate, 13: Pixel electrode, 14: Counter electrode, 15, 15a: First insulating film, 16, 16a: Second insulating film, 17: First polymer layer, 18: Second polymer layer, 19: Liquid crystal layer, 20: Encapsulating material, 21: Polymer, 30: Mask

Claims

1. (a) Forming a first insulating film on one side of the first substrate, (b) Forming a second insulating film on one side of the second substrate, (c) Forming a liquid crystal layer between each of the one surfaces of the first substrate and the second substrate, (d) By irradiating the liquid crystal layer with light from a direction oblique to the other surface of at least one of the first substrate and the second substrate that is opposite to the one surface, a first polymer layer having polymer arranged in a direction inclined with respect to one surface of the first substrate is formed on the surface of the first insulating film that is opposite to the liquid crystal layer, and a second polymer layer having polymer arranged in a direction inclined with respect to one surface of the second substrate is formed on the surface of the second insulating film that is opposite to the liquid crystal layer. Includes, In (c) above, the liquid crystal material used to form the liquid crystal layer contains a monomer that is polymerizable by light and is a trans isomer having a double bond in its central part. A method for manufacturing liquid crystal elements.

2. The oblique direction during light irradiation in (d) above is a direction that forms an angle of 30° or more and 60° or less with respect to the other surface of either the first substrate or the second substrate. A method for manufacturing a liquid crystal element according to claim 1.

3. The monomer is a monomer that can be polymerized by ultraviolet light. A method for manufacturing a liquid crystal element according to claim 1.

4. The monomer has two or more polymerization sites. A method for manufacturing a liquid crystal element according to claim 1.

5. The monomer is a monomer containing a chalcone group. A method for manufacturing a liquid crystal element according to claim 1.

6. The first insulating film and the second insulating film are inorganic insulating films formed using silica or titania. A method for manufacturing a liquid crystal element according to claim 1.

7. The first insulating film and the second insulating film are vertically aligned films having an inorganic main chain and side chains, and are vertically aligned films that have not undergone any orientation treatment. A method for manufacturing a liquid crystal element according to claim 1.

8. The (d) above includes placing a mask that partially blocks light from the liquid crystal layer on the other side of the first or second substrate and performing the light irradiation through the mask, wherein the light irradiation is performed each time the placement of the mask is changed. A method for manufacturing a liquid crystal element according to claim 1.

9. A first substrate having a first insulating film on one side, A second substrate having a second insulating film on one side, and arranged with a gap between it and the first substrate, with the first insulating film and the second insulating film facing each other. A liquid crystal layer disposed in the gap between the first substrate and the second substrate, A first polymer layer having a polymer arranged on the surface of the first insulating film facing the liquid crystal layer and in a direction inclined with respect to one surface of the first substrate, A second polymer layer is disposed on the surface of the second insulating film facing the liquid crystal layer and has a polymer arranged in a direction inclined with respect to one surface of the second substrate, Includes, The first insulating film and the second insulating film are inorganic insulating films formed using silica or titania, or vertically aligned films having an inorganic main chain and side chains. Liquid crystal element.

10. The liquid crystal layer is uniformly oriented under the orientation-regulating force of the first polymer layer and / or the second polymer layer. The liquid crystal element according to claim 9.

11. The polymer in each of the first and second polymer layers is formed by polymerization of trans monomers having a double bond in the central part. The liquid crystal element according to claim 9.

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