Liquid crystal element and method for manufacturing liquid crystal element

Abstract

Provided are: a method for producing a liquid crystal element which is easy to produce without requiring a special alignment film; and the like. A method for manufacturing a liquid crystal element includes: forming a liquid crystal layer by disposing a liquid crystal material between a first substrate and a second substrate; and forming a first polymer layer on the surface of the first insulating film facing the liquid crystal layer by irradiating the liquid crystal layer with light through the first substrate or the second substrate from a direction that is oblique to the other surface of the first substrate or the second substrate facing the one surface. A first polymer layer is formed on a surface of the second insulating film facing the liquid crystal layer, the first polymer layer having a polymer disposed in a direction inclined with respect to one surface of the first substrate, and a second polymer layer having a polymer disposed in a direction inclined with respect to one surface of the second substrate is formed on a surface of the second insulating film facing the liquid crystal layer. The liquid crystal material contains a photopolymerizable monomer, and the monomer is a trans-isomer having a double bond in the center thereof.

Description

Technical Field The present disclosure relates to a liquid crystal element and a method for manufacturing the liquid crystal element. Background Art Japanese Patent Publication No. 2019-128383 (Patent Document 1) describes a liquid crystal display device, which has: a pair of substrates; a liquid crystal layer, which is arranged between the pair of substrates; an alignment film, which is arranged on the surface of the liquid crystal layer side of at least one of the pair of substrates; and a polymer layer, which is arranged between the liquid crystal layer and each alignment film. In the 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 acts as a polymerization initiator, and each polymer layer contains a second polymer formed by polymerizing at least one monomer having a chalcone group. Prior art literature Patent Literature Patent Document 1: Japanese Patent Application Publication No. 2019-128383 Summary of the invention Problems to be solved by the invention One of the objects of a specific embodiment of the present disclosure is to provide a method for producing a liquid crystal element that does not require a special alignment film and can be easily produced. Another object of a specific embodiment of the present disclosure is to provide a liquid crystal element obtained by the above-mentioned production method. Means for solving problems

[0001] A method for manufacturing a liquid crystal element according to one embodiment 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 each of the above-mentioned surfaces of the first substrate and the above-mentioned second substrate; and (d) irradiating the above-mentioned liquid crystal layer with light from a direction oblique to another surface opposite to the above-mentioned surface of at least one of the above-mentioned first substrate and the above-mentioned second substrate, thereby forming a first polymer layer on the surface of the above-mentioned first insulating film opposite to the above-mentioned liquid crystal layer, the first polymer layer having a polymer arranged in a direction inclined relative to the above-mentioned surface of the first substrate, and forming a second polymer layer on the surface of the above-mentioned second insulating film opposite to the above-mentioned liquid crystal layer, the second polymer layer having a polymer arranged in a direction inclined relative to the above-mentioned surface of the second substrate, wherein the liquid crystal material used for forming the above-mentioned liquid crystal layer in the above-mentioned (c) contains a monomer that can be photopolymerized, and the monomer is a trans isomer having a double bond in its central portion.

[0002] A liquid crystal element of one embodiment of the present invention 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, and configured with a gap set between the first substrate and the second insulating film in a state where the first insulating film and the second insulating film are opposite to each other; (c) a liquid crystal layer configured in the gap between the first substrate and the second substrate; (d) a first polymer layer configured on the surface of the first insulating film opposite to the liquid crystal layer, comprising a polymer configured in a direction inclined relative to one side of the first substrate; and (e) a second polymer layer configured on the surface of the second insulating film opposite to the liquid crystal layer, comprising a polymer configured in a direction inclined relative to one side of the second substrate. According to the above configuration, a method for producing a liquid crystal element that does not require a special alignment film and can be easily produced is provided. In addition, a liquid crystal element obtained by the production method is provided. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 (A) is a schematic cross-sectional view for explaining the structure of the liquid crystal element according to the first embodiment. Figure 1 (B) is a diagram schematically showing a polymer included in the first polymer layer or the second polymer layer. Figure 2 (A)~ Figure 2 (F) is a diagram for explaining the method for manufacturing the liquid crystal element according to the first embodiment. Figure 3 (A)~ Figure 3 (C) is a diagram for explaining the method for manufacturing the liquid crystal element according to the first embodiment. Figure 4 (A) and Figure 4 (B) is a diagram for explaining a modified example of the step of irradiating the liquid crystal layer with light. Figure 5 (A) is a schematic cross-sectional view for explaining the structure of the liquid crystal element according to the second embodiment. Figure 5 (B) is a schematic cross-sectional view for explaining the structure of the liquid crystal element according to the third embodiment. Figure 6 This is a diagram showing the relationship between the irradiation angle and the pretilt angle during light irradiation in the liquid crystal element of Example 1 produced using a monomer containing a chalcone group. Figure 7 This is a diagram showing the relationship between the irradiation angle and the pretilt angle when the liquid crystal element of Example 2 is irradiated with light. DETAILED DESCRIPTION Figure 1(A) is a schematic cross-sectional view for explaining the structure of the liquid crystal element of the first embodiment. The illustrated liquid crystal element 1 is configured to include a first substrate 11 and a second substrate 12 arranged opposite to 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. The first substrate 11 and the second substrate 12 are transparent substrates that are rectangular in plan view, for example, and are arranged so that one side of each other faces each other. As the first substrate 11 and the second substrate 12, for example, a glass substrate or a plastic substrate can be used. Spherical spacers (not shown) composed of, for example, a resin film are dispersedly arranged between the first substrate 11 and the second substrate 12, and the substrate gap is maintained at a desired size (for example, about several μm) by these spherical spacers. It should be noted that, instead of the 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. In addition, although not shown in the figure, the liquid crystal element 1 may be provided with a polarizing plate or a polarizing element on the outer side of each of the first substrate 11 and the second substrate 12 (the side not facing the liquid crystal layer 19), and an optical compensation plate such as a phase difference plate may be provided between each polarizing plate and the first substrate 11 or the second substrate 12. A plurality of pixel electrodes 13 are provided on one surface of the first substrate 11. The 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 where each pixel electrode 13 faces the counter electrode 14. The counter electrode 14 is provided on one surface side of the second substrate 12. The counter electrode 14 is provided integrally so as to face each pixel electrode 13 of the first substrate 11. The counter electrode 14 is formed by appropriately patterning a transparent conductive film such as indium tin oxide (ITO), for example. 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 in a mutually opposed state with a gap provided therebetween. As an example, the first insulating film 15 and the second insulating film 16 are preferably inorganic insulating films formed using silicon dioxide or titanium dioxide, for example, titanium siloxane-based inorganic insulating films can be used. The first insulating film 15 and the second insulating film 16 are not subjected to an orientation treatment such as a rubbing treatment. The first polymer layer 17 is arranged so as to contact the liquid crystal layer 19 on the surface of the first insulating film 15 facing the liquid crystal layer 19. In addition, the second polymer layer 18 is arranged so as 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 includes 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 includes a plurality of polymers (polymers) arranged in a direction inclined with respect to one surface of the second substrate 12. 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 formed, for example, using a nematic liquid crystal material having fluidity. The liquid crystal layer 19 is formed, for example, using a liquid crystal material having negative dielectric constant anisotropy. The layer thickness of the liquid crystal layer 19 can be, for example, about 4 μm. The liquid crystal layer 19 is oriented by the orientation restraining force brought by the first polymer layer 17 and the second polymer layer 18, and when no voltage is applied (including when a voltage below a threshold is applied), the liquid crystal layer 19 has a pretilt angle of, for example, 85° to 89.9° and is uniformly oriented. The sealing material 20 is provided between the first substrate 11 and the second substrate 12 to surround the liquid crystal layer 19 and seal the liquid crystal layer 19. As shown in the figure, in this embodiment, the sealing material 20 is provided 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. Figure 1 (B) is a diagram schematically showing the polymers contained in the first polymer layer or the second polymer layer. Each polymer 21 is arranged obliquely on one side 22 of each of the first insulating film 15 and the second insulating film 16. In other words, each polymer 21 is arranged in a direction inclined relative to one side of the first substrate 11 and the second substrate 12. Each polymer 21 in the first embodiment is a monomer of a trans isomer having a double bond in the central part of the molecule that is polymerized by light irradiation (ultraviolet irradiation in this embodiment), and has two or more polymerization sites. In addition, each polymer 21 is preferably formed by polymerizing a monomer containing a chalcone group. In the example shown in the figure, each polymer 21 is uniformly arranged toward the upper left direction in the figure. The "uniform" mentioned here does not mean that each polymer 21 is strictly oriented in the same direction, but means that it is roughly oriented in the same direction. These polymers 21 exert an orientation constraint force on the liquid crystal layer 19, so that the liquid crystal molecules of the liquid crystal layer 19 can be uniformly oriented. It should be noted that only the polymer 21 is shown here, but monomers may also remain on one side 22 of each of the first insulating film 15 and the second insulating film 16. As an example, the expression mechanism of the orientation restraining force when using a monomer containing a chalcone group is speculated as follows. There are three reactive parts in the molecule of the monomer containing a chalcone group (RM molecule), and the internal olefin (double bond in the center of the molecule) is more difficult to photopolymerize than the reactive parts at both ends. The double bond in the central part of the molecule can take cis-trans isomers, but the trans isomer is dominant. In the case of the trans isomer, it is believed that the direction of the molecule is slightly tilted due to the double bond in the central part of the RM molecule. Before light irradiation, the liquid crystal molecules of the liquid crystal layer 19 are generally completely vertically oriented, and the RM molecules are also oriented in the same direction, but because they are trans isomers, each molecule is slightly tilted. When the liquid crystal layer 19 is irradiated with light from an oblique direction, the internal olefin in the part that is susceptible to ultraviolet light is polymerized, and the RM molecules as the residual trans isomers are tilted, so it is believed that this produces an effect of slightly orienting the liquid crystal molecules. Figure 2 (A)~ Figure 2 (F) and Figure 3 (A)~ Figure 3 (C) is a diagram for explaining the method for manufacturing a liquid crystal element according to Embodiment 1. It should be noted that, as long as no contradiction or detuning occurs, the steps may be performed in a different order or in parallel, and other steps (such as a cleaning step, etc.) not shown or described may be appropriately added. First, a first substrate 11 ( Figure 2 (A)), and prepare a second substrate 12 having a counter electrode 14 on one side 12a ( Figure 2 (B)). As described above, each pixel electrode 13 and the counter electrode 14 are obtained by patterning an ITO film formed on one surface of each of the first substrate 11 and the second substrate 12 using, for example, photolithography technology. Next, a first insulating film 15 ( Figure 2 Similarly, on one surface 12a of the second substrate 12, a second insulating film 16 is formed so as to cover the counter electrode 14 ( Figure 2 (D)). The first insulating film 15 and the second insulating film 16 are preferably inorganic insulating films formed using, for example, silicon dioxide or titanium dioxide, and for example, titanium siloxane-based inorganic insulating films can be used. There is no particular limitation on the film forming method of the first insulating film 15 and the second insulating film 16, and sputtering, evaporation, CVD, printing, etc. can be used appropriately. In particular, from the perspective of simplifying the process, it is preferred to form the first insulating film 15 and the second insulating film 16 using an insulating film such as a titanium siloxane-based inorganic insulating film to which a printing method can be applied. Next, a sealing material 20 ( Figure 2 (E)). In the example shown in the figure, the sealing material 20 is applied to one side 12a of the second substrate 12, but the sealing material 20 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 controlling the gap are scattered on one side of the substrate (the first substrate 11 in this embodiment) on which the sealing material 20 is not applied. Next, the first substrate 11 and the second substrate 12 are bonded together in a state where the first insulating film 15 and the second insulating film 16 are opposed to each other ( Figure 2 (F)). A gap is provided between the first substrate 11 and the second substrate 12 via a spherical spacer. Next, a liquid crystal material is injected into the gap between the first substrate 11 and the second substrate 12 through an injection port (a portion where a portion of the sealing material 20 is opened) by vacuum injection, thereby forming a liquid crystal layer 19 ( Figure 3 In this embodiment, a liquid crystal material containing a monomer that can be polymerized by light (especially ultraviolet light) is used, and the monomer is a trans isomer having a double bond in its central portion. The monomer contained in the liquid crystal material is preferably a monomer having two or more polymerization sites, and is preferably a monomer containing a chalcone group. It should be noted that when injecting the liquid crystal material, the ODF (One Drop Fill) method can also be used. In this case, after forming the sealing material 20 and before bonding the first substrate 11 and the second substrate 12, the liquid crystal material is dripped (arranged) in the area surrounded by the sealing material 20, and then the first substrate 11 and the second substrate 12 are bonded. 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 opposite to the first substrate 11 or the second substrate 12 ( Figure 3 (B)). In this process, it is more preferable from the manufacturing point of view not to apply voltage to the liquid crystal layer 19. It should be noted that it does not deny the application of voltage to the liquid crystal layer 19 during light irradiation. If voltage is applied, no voltage is applied to the liquid crystal layer 19 for a certain period (for example, 30 seconds to 2 minutes) from the start of light irradiation, and light is irradiated from an oblique direction as described above, and then a voltage is applied to the liquid crystal layer 19. It is believed that the pretilt angle can be actively controlled according to the voltage. There is no special limitation on the direction of light irradiation when applying voltage, and it can continue to be set to the oblique direction, or it can be set to a direction other than this (for example, the front direction). Here, in this embodiment, a photocurable substance (resin, etc.) is used as the sealing material 20, so that Figure 3The sealing material 20 is cured at the same time in the process shown in (B). As a result, compared with the conventional manufacturing process, there is no need to add a new process for forming the first polymer layer 15 and the second polymer layer 16, and the manufacturing method can be simplified. It should be noted that the case of using a photocurable resin as a sealing material is described here, but a thermosetting resin can also be used. As the end sealing material (injection port sealing material) for sealing the injection port in the case of vacuum injection, a photocurable resin is preferably used, which can be Figure 3 The end sealing material is cured simultaneously in the step (B) of . Thus, compared with the conventional manufacturing process, there is no need to add a new step for forming the first polymer layer 15 and the second polymer layer 16, and the manufacturing method can be simplified. In the present embodiment, ultraviolet light is irradiated from a direction oblique to the other surface 12b opposite to the one surface 12a of the second substrate 12. For example, if the normal line a relative to the other surface 11 of the second substrate 12 is used as a reference, ultraviolet light UV is irradiated from a direction oblique to form an angle θ with the normal line a. The angle θ can be appropriately set, for example, it can be set between 30° and 60°. It should be noted that light irradiation can be performed from a direction oblique to the other surface of the first substrate 11, and light irradiation can also be performed on both the other surface side of the first substrate 11 and the other surface side of the second substrate from a direction oblique to each other surface. The above-mentioned light irradiation polymerizes the monomers contained in the liquid crystal layer 19. As a result, the first polymer layer 15 is formed on the first substrate 11 side, and the 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 are respectively as described above. Figure 1 As shown in (B), the polymer or monomer is arranged in a direction inclined relative to each surface of the first substrate 11 and the second substrate. The first polymer layer 15 and the second polymer layer 16 exert an alignment restraining force on the liquid crystal layer 19, and the liquid crystal layer 19 is uniformly aligned ( Figure 3 In summary, the liquid crystal element 1 is completed. Figure 4 (A) and Figure 4 (B) is a diagram for explaining a modified example of the process of irradiating light to the liquid crystal layer. Figure 4 As shown in (A), a mask 30 partially shielding the left area of ​​the liquid crystal layer 19 is arranged on the other side of the second substrate 12, and light irradiation is performed through the mask 30. Figure 4 As shown in (B), the arrangement of the mask 30 is changed so as to partially shield the right side region of the liquid crystal layer 19 in the figure, and light irradiation is performed through the mask 30. In the example shown in the figure, Figure 4In the step (A) shown in FIG. 1 , light is irradiated from a direction inclined at an angle θ1 clockwise from the normal line of the second substrate 12. Figure 4 In the process shown in (B), light irradiation is performed from a direction inclined at an angle θ2 counterclockwise from the normal line of the second substrate 12. It should be noted that the setting of angle θ1 and angle θ2 is an example, and angle θ1 and angle θ2 can also be set in a manner that the angles are different in the same direction (clockwise or counterclockwise). For example, each process sets the light irradiation direction clockwise from the normal line of the second substrate 12, and can be set to angle θ1=30° and angle θ2=45°. Thereby, the pretilt angle of the liquid crystal layer 19 can be set to different sizes or directions corresponding to areas with different light irradiation directions. In addition, the number of times the configuration of the mask 30 is changed is not limited to the above-mentioned two times, and a larger number of times can also be set. Figure 5 (A) is a schematic cross-sectional view for explaining the structure of the liquid crystal element according to the second embodiment. Figure 5 The liquid crystal element 1a of the second embodiment shown in (A) is different from the liquid crystal element 1 of the first embodiment in that the first insulating film 15 and the second insulating film 16 are respectively changed to the first insulating film 15a and the second insulating film 16a composed of vertical orientation films, but the other structures are the same. As the first insulating film 15a and the second insulating film 16a, vertical orientation films with inorganic main chains and side chains are used respectively. In addition, the first insulating film 15a and the second insulating film 16a are not subjected to orientation treatment such as friction treatment. Moreover, the first polymer layer 17 is arranged between the first insulating film 15a and the liquid crystal layer 19, and the second polymer layer 18 is arranged between the second insulating film 16a and the liquid crystal layer 19. The liquid crystal element 1a of the second embodiment can also obtain the same effect as the liquid crystal element 1 of the first embodiment. Figure 5 (B) is a schematic cross-sectional view for explaining the structure of the liquid crystal element according to the third embodiment. Figure 5 The liquid crystal element 1b of the third embodiment shown in (B) is different from the liquid crystal element 1 of the first embodiment in that the first insulating film 15 and the second insulating film 16 are omitted, respectively, and the other structures are the same. In the 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. The liquid crystal element 1a of the third embodiment can also obtain the same effect as the liquid crystal element 1 of the first embodiment. (Example 1) A liquid crystal element of an example having the structure of the liquid crystal element 1 of the first embodiment is produced. Glass substrates are used as the first substrate 11 and the second substrate 12, respectively, and titanium siloxane-based inorganic insulating films are used as the first insulating film 15 and the second insulating film 16. No orientation treatment such as rubbing treatment is performed on the first insulating film 15 and the second insulating film 16. The layer thickness of the liquid crystal layer 19 is about 4 μm. As a liquid crystal material, a nematic liquid crystal material with negative dielectric anisotropy is used. In the liquid crystal material, as a monomer for forming the first polymer layer 17 and the second polymer layer 18, a monomer containing a chalcone group or a monomer not containing a chalcone group is added at 0.1 wt%, 0.2 wt%, 0.5 wt% or 1.0 wt%. It should be noted that the addition amount can be adjusted, for example, at 0.1 wt% to 5 wt%. The monomer containing a chalcone group is a trans isomer having a double bond also in the central part of the molecule, and has the characteristic of having two or more polymerization sites. In the light irradiation step for the liquid crystal layer 19, the light is irradiated from a direction which is 45° relative to the second substrate 12 (see Figure 3 (B)) irradiated with ultraviolet light. The irradiation amount of ultraviolet light is 20J / cm 2 (=28mW / cm 2 × 12 min). It should be noted that a self-aligning agent may be added to the liquid crystal material at a level of 0.1 wt % to 10 wt %. Comparison of the appearance of a liquid crystal element produced using a monomer containing a chalcone group and a liquid crystal element produced using a monomer not containing a chalcone group shows that the former tends to have better alignment uniformity of the liquid crystal layer 19 . Figure 6 : is a graph showing the relationship between the irradiation angle and the pretilt angle when the liquid crystal element of Example 1 produced using a monomer containing a chalcone group is irradiated with light. The amount of monomer added is set to four types: 0.1wt%, 0.2wt%, 0.5wt%, and 1.0wt%. The irradiation angle θ (refer to Figure 3 (B)) is set to three modes of 30°, 45°, and 60°. When the monomer addition amount is 0.1wt% and 0.2wt%, the pretilt angle is almost independent of the irradiation angle during light irradiation and is 89.9° to 90°. Even when the irradiation angle is 60°, the pretilt angle is about 89.9°. In the case of desiring to obtain a vertically oriented liquid crystal layer 19 with a pretilt angle of 90° or a roughly vertically oriented liquid crystal layer 19 with a pretilt angle of about 89.9°, it is considered beneficial to ensure a large margin for the error of the irradiation angle during light irradiation. On the other hand, it can be seen that: when the amount of monomer added is 0.5wt% and 1.0wt%, the dependence of the pretilt angle on the irradiation angle during light irradiation is more clearly manifested. Specifically, the pretilt angle is obtained in the range of 88.0° to 89.7°. In addition, it is observed that the larger the irradiation angle, the smaller the pretilt angle tends to be. In the case where it is desired to actively give the liquid crystal layer 19 a pretilt angle, it is possible to control the pretilt angle by the irradiation angle, so it is considered to be beneficial. (Example 2) A liquid crystal element of an example having the structure of the liquid crystal element 1a of the second embodiment is produced. Glass substrates are used as the first substrate 11 and the second substrate 12, respectively, and vertical alignment films having an inorganic main chain and side chains are used as the first insulating film 15a and the second insulating film 16a, respectively. The first insulating film 15a and the second insulating film 16a are not subjected to alignment treatment such as rubbing treatment. The layer thickness of the liquid crystal layer 19 is about 4 μm. As a liquid crystal material, a nematic liquid crystal material having a negative dielectric anisotropy is used. In the liquid crystal material, a monomer containing a chalcone group is added at 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 also in the central part of the molecule, and has the characteristic of having two or more polymerization sites. In the light irradiation step of the liquid crystal layer 19, the irradiation angle θ (refer to Figure 3 (B)) was set to 30°, 45°, and 60°. The UV irradiation was set to 20 J / cm 2 (=28mW / cm 2 × 12 min). It should be noted that a self-aligning agent may be added to the liquid crystal material at a level of 0.1 wt % to 10 wt %. Figure 7 This is a diagram showing the relationship between the irradiation angle and the pretilt angle when the liquid crystal element of Example 2 is irradiated with light. It can be seen that the pretilt angle is dependent on the irradiation angle when the light is irradiated. Specifically, the pretilt angle is obtained in the range of 89.4° to 88.9°. In addition, it is observed that the larger the irradiation angle, the smaller the pretilt angle. (Example 3) The liquid crystal element was prepared under the same conditions as in the first embodiment, and the light irradiation was performed multiple times using a mask. Specifically, in the light irradiation step (refer to Figure 4 (A) Figure 4 In (B), the area not shielded by the mask 30 is irradiated with light from a direction inclined 45° clockwise from the normal to the second substrate 12. Then, the configuration of the mask 30 is changed, and the area not shielded by the changed mask 30 is irradiated with light from a direction inclined 30° counterclockwise from the normal to the second substrate 12. The pretilt angle of the obtained liquid crystal element was measured. As a result, the pretilt angle was 88.4° in the area with an illumination angle of 45° during light irradiation, and the pretilt angle was also 88.4° in the area with an illumination angle of 30° during light irradiation. In addition, the best visual recognition directions (directions with pretilt angles) in the area with an illumination angle of 45° and the area with an illumination angle of 30° during light irradiation differed by 180°. That is, multi-domain orientation was obtained. According to the above-described embodiments and examples, a method for manufacturing a liquid crystal element that does not require a special alignment film and can be easily manufactured is provided. In addition, a liquid crystal element obtained by the manufacturing method is provided. It should be noted that the present disclosure is not limited to the contents of the above-mentioned embodiments, and various modifications can be made within the scope of the gist of the present disclosure. For example, the numerical conditions and the like described in the above-mentioned embodiments and the like are merely examples, and are not limited to these numerical conditions and the like. The present disclosure has the following additional features. (Note 1) A method for manufacturing a liquid crystal element, comprising: (a) forming a first insulating film on one side of a first substrate; (b) forming a second insulating film on one side of the second substrate; (c) forming a liquid crystal layer between 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 facing the one surface, thereby forming a first polymer layer on the surface of the first insulating film facing the liquid crystal layer, the first polymer layer having a polymer arranged in a direction oblique to the one surface of the first substrate, and forming a second polymer layer on the surface of the second insulating film facing the liquid crystal layer, the second polymer layer having a polymer arranged in a direction oblique to the one surface of the second substrate, The liquid crystal material used for forming the liquid crystal layer in (c) above contains a photopolymerizable monomer, which is a trans isomer having a double bond in its central portion. (Note 2) A method for manufacturing a liquid crystal element as described in Appendix 1, wherein the oblique direction during the light irradiation in (d) is a direction forming an angle of 30° to 60° relative to the other surface of either the first substrate or the second substrate. (Note 3) The method for producing a liquid crystal element according to Appendix 1 or 2, wherein the monomer is a monomer that can be polymerized by ultraviolet light. (Note 4) The method for producing a liquid crystal element according to any one of Appendixes 1 to 3, wherein the monomer has two or more polymerization sites. (Note 5) The method for producing a liquid crystal element according to any one of Appendixes 1 to 4, wherein the monomer is a monomer containing a chalcone group. (Note 6) The method for manufacturing a liquid crystal element according to any one of Supplementary Notes 1 to 5, wherein the first insulating film and the second insulating film are inorganic insulating films formed using silicon dioxide or titanium dioxide. (Note 7) The method for manufacturing a liquid crystal element according to any one of Appendixes 1 to 5, wherein the first insulating film and the second insulating film are vertical alignment films having an inorganic main chain and a side chain and not subjected to an alignment treatment. (Note 8) A method for manufacturing a liquid crystal element as described in any one of Notes 1 to 7, wherein the above (e) includes configuring a mask for partially shielding the above liquid crystal layer on the above other surface side of the above first substrate or the above second substrate, performing the above light irradiation through the mask, and performing the above light irradiation each time the configuration of the above mask is changed. (Note 9) A liquid crystal element, comprising: A first substrate having a first insulating film on one side; a second substrate having a second insulating film on one side thereof, and arranged with a gap provided between the first substrate and the second insulating film in a state where the first insulating film and the second insulating film are opposed to each other; a liquid crystal layer disposed in the gap between the first substrate and the second substrate; a first polymer layer disposed on a surface of the first insulating film facing the liquid crystal layer, and comprising a polymer disposed in a direction inclined with respect to one surface of the first substrate; and The second polymer layer is disposed on a surface of the second insulating film facing the liquid crystal layer and includes a polymer disposed in a direction inclined with respect to one surface of the second substrate. (Note 10) The liquid crystal element according to Supplementary Note 9, wherein the first insulating film and the second insulating film are inorganic insulating films formed using silicon dioxide or titanium dioxide. (Note 11) The liquid crystal element according to Appendix 9 or 10, wherein the liquid crystal layer is aligned uniformly due to an alignment restraining force provided by the first polymer layer and / or the second polymer layer. (Note 12) The liquid crystal element according to any one of Appendixes 9 to 11, wherein the polymer in each of the first polymer layer and the second polymer layer is obtained by polymerizing a trans isomer monomer having a double bond in a central portion. Explanation of symbols 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: sealing material, 21: polymer, 30: mask.

Claims

1. A method for manufacturing a liquid crystal element, comprising: (a) forming a first insulating film on one side of a first substrate; (b) forming a second insulating film on one side of the second substrate; (c) forming a liquid crystal layer between the first substrate and the second substrate; and (d) forming a first polymer layer on a surface of the first insulating film facing the liquid crystal layer, the first polymer layer having a polymer arranged in a direction inclined relative to the surface of the first substrate, and forming a second polymer layer on a surface of the second insulating film facing the liquid crystal layer, the second polymer layer having a polymer arranged in a direction inclined relative to the surface of the second substrate, by irradiating the liquid crystal layer from a direction oblique to the other surface of at least one of the first substrate and the second substrate, The liquid crystal material used for forming the liquid crystal layer in (c) above contains a photopolymerizable monomer, which is a trans isomer having a double bond in its central portion.

2. The method for manufacturing a liquid crystal element according to claim 1, wherein: The oblique direction during the light irradiation in (d) is a direction forming an angle of 30° to 60° with respect to the other surface of either the first substrate or the second substrate.

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

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

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

6. The method for manufacturing a liquid crystal element according to claim 1, wherein: The first insulating film and the second insulating film are inorganic insulating films formed using silicon dioxide or titanium dioxide.

7. The method for manufacturing a liquid crystal element according to claim 1, wherein: The first insulating film and the second insulating film are vertical alignment films that have an inorganic main chain and side chains and are not subjected to an alignment treatment.

8. The method for manufacturing a liquid crystal element according to claim 1, wherein: The (e) includes disposing a mask for partially shielding the liquid crystal layer on the other surface side of the first substrate or the second substrate, performing the light irradiation through the mask, and performing the light irradiation every time the arrangement of the mask is changed.

9. A liquid crystal element, comprising: A first substrate having a first insulating film on one side; a second substrate having a second insulating film on one side thereof, and arranged with a gap provided between the first substrate and the second insulating film in a state where the first insulating film and the second insulating film are opposed to each other; a liquid crystal layer disposed in the gap between the first substrate and the second substrate; a first polymer layer disposed on a surface of the first insulating film facing the liquid crystal layer, and comprising a polymer disposed in a direction inclined with respect to one surface of the first substrate; and The second polymer layer is disposed on a surface of the second insulating film facing the liquid crystal layer and includes a polymer disposed in a direction inclined with respect to one surface of the second substrate.

10. The liquid crystal element according to claim 9, wherein The first insulating film and the second insulating film are inorganic insulating films formed using silicon dioxide or titanium dioxide.

11. The liquid crystal element according to claim 9, wherein The liquid crystal layer is aligned uniformly due to the alignment restraining force provided by the first polymer layer and / or the second polymer layer.

12. The liquid crystal element according to claim 9, wherein The polymer in each of the first polymer layer and the second polymer layer is obtained by polymerizing a trans-isomer monomer having a double bond in the center portion.

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