JP6948634B2 - Liquid crystal element and its manufacturing method - Google Patents

Description

The present invention relates to a liquid crystal element and a method for manufacturing the same.

With the expansion of the liquid crystal display market, its applications are also diversifying. A liquid crystal display generally has a color filter substrate, a TFT substrate, and a liquid crystal layer in which a liquid crystal material is filled in a cell gap of several microns between them. Therefore, it is very important to keep the cell gap of this liquid crystal layer constant.

Usually, the cell gap is adjusted by a structure having a certain height called a spacer. The spacer is formed, for example, by arranging spherical fine particles whose particle size is controlled to be constant on a substrate, or by applying a photosensitive resin on the substrate with a constant film thickness and exposing and developing through a mask. NS.

In recent years, it is expected that a flexible liquid crystal display using a flexible plastic substrate as a substrate will enter the market. While the flexible liquid crystal display is used in a state of being arbitrarily bent, there is a problem that cell gap unevenness is likely to occur and the display state is likely to be uneven.

On the other hand, for example, Patent Document 1 has a color filter substrate, a TFT substrate, and spherical fine particles (spacers) arranged between the substrates and adhered to the substrates via an adhesive resin. Liquid crystal displays are disclosed. In this liquid crystal display, a color filter substrate coated and dried with a spacer ink containing spherical fine particles and a thermosetting polymer liquid and a TFT substrate coated with a sealant are bonded and heat-treated (thermosetting), and then heat-treated (thermosetting). Manufactured by injecting a liquid crystal material. Further, as those substrates, plastic substrates such as polyethylene terephthalate (PET) and polycarbonate (PC) are disclosed.

Japanese Unexamined Patent Publication No. 2012-220877

By the way, an alignment film for orienting the liquid crystal material is usually formed on the surface of the substrate of the liquid crystal element. The alignment film is usually formed by applying a solution containing polyimide and then annealing it at a high temperature of 200 ° C. or higher. Therefore, the substrate is required to have heat resistance to withstand it. Further, in a flexible liquid crystal display, it is desired to make the thickness of the substrate as thin as possible from the viewpoint of improving bendability and weight reduction. However, none of the conventional plastic substrates as shown in Patent Document 1 has high heat resistance and sufficient thinness, that is, sufficient flexibility.

Further, the liquid crystal display manufactured by the method shown in Patent Document 1 does not have sufficient adhesive strength between the spherical fine particles and the substrate, and can sufficiently suppress cell gap unevenness when the liquid crystal display is bent. There wasn't.

Especially in a flexible liquid crystal display, it is desired to make the thickness of the substrate as thin as possible from the viewpoint of improving bendability and weight reduction; in a flexible liquid crystal display having such a thin substrate, cell gap unevenness further occurs at the time of bending. Since it is easy, it is desired that cell gap unevenness can be suppressed to a high degree.

The present invention has been made in view of the above circumstances, and provides a liquid crystal element having high heat resistance, suppressing cell gap unevenness at the time of bending, and having excellent bending resistance, and a method for manufacturing the same. The purpose is.

（一般式（１）において、
Ｒ_１は、脂環式炭化水素構造を含む炭素原子数４〜１５の２価の基、又は炭素原子数５〜１２の２価の直鎖状脂肪族基を表し、
Ｙ_１は、芳香環を含む炭素原子数６〜２７の４価の基を表す）

（一般式（２）において、
Ｒ_２は、芳香環を含む炭素原子数６〜２７の２価の基を表し、
Ｙ_２は、脂環式炭化水素構造を含む炭素原子数４〜１２の４価の基を表す）
［１１］ 一の支持体上に塗布形成された下記（１）〜（６）を全て満たす一の基板と、他の支持体上に塗布形成された下記（１）〜（６）を全て満たす他の基板とを得る工程と、
（１）厚さ１０μｍにおけるＬ^＊ａ^＊ｂ^＊表色系のｂ^＊値が５以下である
（２）厚さ１０μｍにおける波長５５０ｎｍでのＲｔｈが１５０ｎｍ以下である
（３）ＪＩＳ Ｐ８１１５に準拠して測定される、厚さ１０μｍにおけるＭＩＴ耐折性試験での耐折回数が１万回以上である
（４）ガラス転移温度が２００℃以上である
（５）厚さが５０μｍ以下である
（６）厚さ１０μｍにおける波長３６５±５ｎｍの最大透過率が１５％以上である
前記一の支持体上に塗布形成された前記一の基板と、前記他の支持体上に塗布形成された前記他の基板と、前記一の基板と他の基板との間に配置され、液晶材料と、光硬化性化合物と、光重合開始剤とを含む液晶組成物からなる層とを有する積層体を得る工程と、
前記積層体から前記他の支持体を剥がし取る工程と、
前記他の支持体が剥がし取られた前記積層体の少なくとも一方の面から光をパターン状に照射して、前記光硬化性化合物を硬化させて、前記一の基板と前記他の基板の少なくとも一方と接合する接合スペーサを形成する工程と、
前記接合スペーサが形成された前記積層体から前記一の支持体を剥がし取り、液晶素子を得る工程とを含む、液晶素子の製造方法。 [1] A plurality of bonding spacers arranged between one substrate, another substrate facing the substrate, the one substrate and the other substrate, and bonded to at least one of the one substrate and the other substrate. The one substrate, the other substrate, and the liquid crystal layer filled in the space partitioned by the bonding spacer, and the one substrate and the other substrate are described in (1) to (1) to the following. A liquid crystal element that satisfies all of (5).
(1) The L ^* a ^* b ^* color system b ^* value at a thickness of 10 μm is 5 or less. (2) The phase difference value Rth in the thickness direction at a wavelength of 550 nm at a thickness of 10 μm is 200 nm or less. 3) The number of fold resistance in the MIT fold resistance test at a thickness of 10 μm measured according to JIS P8115 is 10,000 or more. (4) The glass transition temperature is 200 ° C or more. (5) Thickness [2] The liquid crystal element according to [1], wherein the bonding spacer is bonded to both the one substrate and the other substrate.
[3] The liquid crystal element according to [1] or [2], wherein the bonding spacer is a cured product of a photocurable compound.
[4] The liquid crystal element according to any one of [1] to [3], wherein the one substrate and the other substrate further satisfy the following (6).
(6) The maximum transmittance at a wavelength of 365 ± 5 nm at a thickness of 10 μm is 15% or more. [5] The shape of the bonding spacer when viewed in a plan view is a line shape, a cross shape, or a grid shape. The liquid crystal element according to any one of 1] to [4].
[6] The liquid crystal element according to [5], wherein the shape of the bonding spacer when viewed in a plan view is a lattice shape.
[7] The ratio of the length A of the long side of the display area partitioned by the lattice-shaped joining spacers to the width B of the joining spacers is A: B = 3: 1 to 300: 1. 6] The liquid crystal element according to.
[8] The liquid crystal element according to any one of [1] to [7], wherein the average distance between adjacent bonding spacers is 50 to 300 μm.
[9] The liquid crystal element according to any one of [1] to [8], wherein the one substrate and the other substrate contain polyimide.
[10] The liquid crystal element according to [9], wherein the polyimide is a polyimide having a structural unit represented by the following general formula (1) or a structural unit represented by the following general formula (2).

(In the general formula (1)
R ₁ represents a divalent group having 4 to 15 carbon atoms or a divalent linear aliphatic group having 5 to 12 carbon atoms including an alicyclic hydrocarbon structure.
Y ₁ represents a tetravalent group having 6 to 27 carbon atoms including an aromatic ring)

(In the general formula (2)
R ₂ represents a divalent group having 6 to 27 carbon atoms including an aromatic ring.
Y ₂ represents a tetravalent group having 4 to 12 carbon atoms including an alicyclic hydrocarbon structure)
[11] One substrate satisfying all of the following (1) to (6) coated and formed on one support and all of the following (1) to (6) coated and formed on another support are satisfied. The process of obtaining other substrates and
(1) L ^* a ^* b ^* color system b ^* value at a thickness of 10 μm is 5 or less (2) Rth at a wavelength of 550 nm at a thickness of 10 μm is 150 nm or less (3) Compliant with JIS P8115 The number of fold resistance in the MIT fold resistance test at a thickness of 10 μm is 10,000 or more (4) The glass transition temperature is 200 ° C or more (5) The thickness is 50 μm or less (6) ) The one substrate coated and formed on the one support having a maximum transmittance of 15% or more at a wavelength of 365 ± 5 nm at a thickness of 10 μm, and the other substrate coated and formed on the other support. A step of obtaining a laminate having a substrate, a layer composed of a liquid crystal material, a photocurable compound, and a liquid crystal composition containing a photopolymerization initiator, which is arranged between the one substrate and the other substrate. ,
The step of peeling off the other support from the laminated body and
Light is radiated in a pattern from at least one surface of the laminate from which the other support has been peeled off to cure the photocurable compound, and at least one of the one substrate and the other substrate is cured. The process of forming a joint spacer to be joined with
A method for manufacturing a liquid crystal element, which comprises a step of peeling off the one support from the laminated body on which the bonding spacer is formed to obtain a liquid crystal element.

According to the present invention, it is possible to provide a liquid crystal element having high heat resistance, suppressing cell gap unevenness at the time of bending, and having excellent bending resistance, and a method for manufacturing the same.

1A to 1C are views showing an example of the shape of the bonding spacer. 2A and 2B are explanatory views showing an example of a display area of the bonding spacer. 3A to 3H are views showing an example of a method for manufacturing a liquid crystal element of the present invention.

In the present specification, the numerical range represented by using "~" means a range including the numerical values before and after "~" as the lower limit value and the upper limit value.

Examples of the plastic substrate used in the conventional flexible liquid crystal display include polycarbonate (PC), cycloolefin polymer (COP), polyethylene terephthalate (PET), and polyethylene naphthalate (PEN). Among these, polycarbonate (PC) is mentioned as a resin having relatively high heat resistance. However, polycarbonate (PC) could not be formed to a thin thickness and did not have sufficient flexibility (flexibility). That is, the plastic substrate used in the conventional flexible liquid crystal display does not have both high heat resistance and high flexibility.

On the other hand, in the present invention, as the substrate of the liquid crystal element, a substrate satisfying the above-mentioned physical properties (1) to (5) is used. Also, a bonding spacer is used to bond to at least one of the two substrates. Since such a bonding spacer is fixed on the substrate even when the liquid crystal element is bent and does not move, the distance between the substrates can be kept constant. By combining these, it is possible to obtain a liquid crystal element having high heat resistance, suppressing cell gap unevenness at the time of bending, and having excellent bending resistance.

Further, by making the shape of the bonding spacer into a grid pattern, it is easy to confine the liquid crystal material in the display area partitioned by the bonding spacer, and the flow of the liquid crystal material when the liquid crystal element is bent can be further suppressed. .. Further, by adjusting the ratio of the longitudinal direction A of the display area partitioned by the lattice-shaped bonding spacers to the width B of the bonding spacers, the adhesive strength with the substrate can be further increased without impairing the display characteristics. .. As a result, cell gap unevenness when the liquid crystal element is bent can be suppressed to a higher degree. The present invention has been made based on such findings.

1. 1. Liquid crystal element The liquid crystal element of the present invention is divided into one substrate, another substrate facing the liquid crystal element, a plurality of bonding spacers arranged between them, one substrate, another substrate, and a bonding spacer. It has a liquid crystal layer filled in the space to be formed. Hereinafter, one substrate and the other substrate are also simply referred to as "boards".

1-1. Substrate ^{(1) L *} a * ^{b *} for a color system of the ^{b *} value of the substrate, ^{b *} values of the ^L * ^a * ^{b *} color system in the thickness 10μm is 5 or less, preferably 4 or less Yes, more preferably 3 or less. When the b ^* value is in this range, the substrate becomes colorless and the transparency of visible light becomes good. That is, it is easy to increase the light transmittance of the liquid crystal element having the substrate.

The L ^* a ^* b ^* color system b ^* value of the substrate can be measured using a Color Cute i type manufactured by Suga Test Instruments. Specifically, after calibrating the tester with a white standard plate, the b ^* value of the substrate can be measured in a transmission mode and a photometric method of 8 ° di. ^{The b *} value in the present invention is a value when the thickness of the substrate is 10 μm, and the b ^* value may be measured for a substrate having a thickness of 10 μm, or a substrate having a different thickness may be measured. b ^{* The} value may be measured and converted into a thickness of 10 μm according to a conventional method.

The L ^* a ^* b ^* color system b ^* value of the substrate can be adjusted, for example, according to the type of resin constituting the substrate and the synthesis conditions. ^{For example, when the substrate contains polyimide, the b *} value is increased by increasing the number of structural units having an alicyclic structure (for example, a structural unit derived from an alicyclic diamine or a structural unit derived from an alicyclic tetracarboxylic dianhydride). Can be lowered. Further, at the time of polyimide synthesis, by lowering the oxygen concentration in an inert atmosphere (for example, under a nitrogen stream), coloring due to oxidation can be suppressed and the b ^* value can be lowered.

(2) Rth The Rth of the substrate at a wavelength of 550 nm at a thickness of 10 μm is 200 nm or less, preferably 120 nm or less, and more preferably 100 nm or less. The lower limit of Rth can be, for example, 0 nm. When the Rth of the substrate is within the range, unintended birefringence is unlikely to occur, so that the display characteristics of the liquid crystal element can be improved.

The Rth of the substrate can be measured by the following method. That is, the refractive index nx in the in-plane slow-phase axis direction (X-axis direction) of the substrate, the refractive index ny in the direction (Y-axis direction) orthogonal to the in-plane slow-phase axis in the surface of the substrate, and the thickness direction ( The refractive index nz in the Z-axis direction) is measured with light at room temperature (20 to 25 ° C.) and a wavelength of 550 nm using an optical material inspection device (model RETS-100) manufactured by Otsuka Electronics Co., Ltd. From the obtained refractive indexes nx, ny, nz and the thickness (d) of the substrate, the phase difference (Rth) in the thickness direction is calculated based on the following formula.
Rth (nm) = [(nx + ny) /2-nz] × d

The in-plane slow-phase axis refers to the axis in the direction in which the refractive index is maximized in the in-plane of the substrate. If the substrate does not have an in-plane slow-phase axis, the X-axis direction can be any one direction in the substrate plane and the Y-axis can be orthogonal to it.

The Rth of the substrate can be adjusted, for example, according to the manufacturing conditions (stretching conditions, etc.) and type of the substrate. For example, when the substrate contains polyimide, a structure in which the refractive index nz in the Z-axis direction (thickness direction) increases (for example, a structural unit derived from an alicyclic diamine or an aliphatic diamine) as derived from the above equation. Rth can be lowered by introducing a relatively flexible structure such as a derived structural unit).

(3) MIT fold resistance The number of fold resistance of the substrate in the MIT fold resistance test at a thickness of 10 μm measured in accordance with JIS P8115 is 10,000 times or more, preferably 20,000 times or more. It is more preferably 30,000 times or more, and further preferably 50,000 times or more. When the number of times of folding in the MIT folding resistance test is 10,000 or more, the flexibility of the liquid crystal element having the substrate can be enhanced.

The MIT folding resistance of the substrate is determined by fixing one end of the test piece with a MIT folding resistance tester (for example, Yasuda Seiki Seisakusho, 307 type, etc.) and then grasping the other end to reciprocally bend the test piece. , It can be measured by counting the number of times of bending until the test piece breaks.

The folding resistance of the substrate can be adjusted, for example, by the type of resin constituting the substrate. When the substrate contains polyimide, the folding resistance can be enhanced by including a structural unit having a relatively flexible structure (for example, a structural unit derived from an alicyclic diamine or a structural unit derived from an aliphatic diamine).

(4) Glass transition temperature The glass transition temperature of the substrate is 200 ° C. or higher, preferably 230 to 370 ° C., more preferably 260 to 370 ° C., and further preferably 280 to 370 ° C. When the glass transition temperature of the substrate is 200 ° C. or higher, for example, it can withstand the heat of the annealing treatment when forming an alignment film or a transparent electrode, and it is possible to prevent the substrate from being deformed or the like. In particular, transparent electrodes such as indium tin oxide (ITO) have higher conductivity when the annealing temperature is raised, so that the glass transition temperature of the substrate is preferably high.

The glass transition temperature of the substrate can be measured by a thermomechanical analyzer (TMA). Specifically, a test piece made of polyimide (width 4 mm × length 20 mm) is heated at a temperature rise rate of 5 in a temperature range of 25 to 350 ° C. using a thermomechanical analyzer (TMA-50) manufactured by Shimadzu Corporation. TMA measurement is performed under the measurement conditions of ° C./min, load 14 g / mm ² , and tension mode, and the glass transition temperature (Tg) is obtained from the inflection point of the obtained temperature-test piece elongation curve.

The glass transition temperature of the substrate can be adjusted by the type of resin constituting the substrate. When the substrate contains polyimide, the glass transition temperature can be adjusted by the equivalent amount of the imide group contained in the polyimide and the structure of the diamine component or the tetracarboxylic acid dianhydride component. For example, the glass transition temperature can be increased by containing a diamine or tetracarboxylic acid dianhydride containing an aromatic ring as the diamine component or the tetracarboxylic acid dianhydride component.

(5) Thickness The thickness of the substrate is 50 μm or less, preferably 0.5 to 30 μm, more preferably 1 to 20 μm, and further preferably 5 to 10 μm. When the thickness of the substrate is within the range, the thickness of the liquid crystal element can be reduced and the flexibility can be enhanced.

(6) Maximum Transmittance The maximum transmittance of the substrate at a wavelength of 365 ± 5 nm at a thickness of 10 μm is preferably 15% or more, more preferably 60% or more, still more preferably 65% or more. .. When the maximum transmittance of the substrate is within this range, not only the light transmittance of the liquid crystal element can be increased, but also the light contained in the liquid crystal composition after the two substrates are laminated via the layer composed of the liquid crystal composition. When the curable compound is cured to form a bonding spacer, the light to be irradiated can be sufficiently transmitted.

The maximum transmittance of the substrate refers to the maximum value of the light transmittance measured by the spectrophotometer within the wavelength range of 365 ± 5 nm. The maximum transmittance in the present invention is a value when the thickness of the substrate is 10 μm. For example, the maximum transmittance may be measured for a substrate having a thickness of 10 μm, or the maximum transmittance of substrates having different thicknesses may be measured, and the measured value is converted into a thickness of 10 μm according to Lambert-Beer's law. You may.

The maximum transmittance of the substrate can be adjusted according to the type of resin constituting the substrate and the synthesis conditions. When the substrate contains polyimide, for example, the maximum transmittance can be increased by containing a structural unit having an alicyclic structure (for example, a structural unit derived from an alicyclic diamine or a structural unit derived from an alicyclic tetracarboxylic dianhydride). Can be improved. Further, at the time of polyimide synthesis, by lowering the oxygen concentration in an inert atmosphere (for example, under a nitrogen stream), coloring due to oxidation can be suppressed and the maximum transmittance can be increased.

It is more preferable that the substrate satisfies all of the above-mentioned (1) to (5) and satisfies all of (1) to (6).

The material constituting the substrate is not particularly limited as long as it is a resin satisfying the above-mentioned physical properties of (1) to (5), preferably (1) to (6). Examples of such resins include polyimide. That is, it is preferable that the substrate contains a polyimide having a structural unit represented by the following general formula (1) and / or general formula (2).

_{R 1} of the general formula (1) represents a divalent group having 4 to 15 carbon atoms or a divalent linear aliphatic group having 5 to 12 carbon atoms including an alicyclic hydrocarbon structure. Examples of R ₁ include the following divalent groups.

Among them, R ₁ is preferably a divalent group having 4 to 15 carbon atoms including an alicyclic hydrocarbon structure, and more preferably the following group.

_{Y 1} of the general formula (1) represents a tetravalent group having 6 to 27 carbon atoms including an aromatic ring. Specific examples of Y ₁ include the following tetravalent groups.

Above all, Y ₁ is preferably the following group.

_{R 2} of the general formula (2) represents a divalent group having 6 to 27 carbon atoms including an aromatic ring. Examples of R ₂ include the following divalent groups.

_{X 1 to} X _{3 in the} above formula independently represent the following divalent groups. _{When a plurality of X 2} or X ₃ are contained in one structural unit, they may be the same or different from each other.

_{Y 2} of the general formula (2) represents a tetravalent group having 4 to 12 carbon atoms including an alicyclic hydrocarbon structure. Examples of Y ₂ include the following tetravalent groups.

The polyimide may contain only one of the structural unit represented by the general formula (1) and the structural unit represented by the general formula (2), or may contain both. Further, the polyimide may further contain a structural unit represented by the general formula (1) and a structural unit other than the structural unit represented by the general formula (2).

The total amount of the structural unit represented by the general formula (1) and the structural unit represented by the general formula (2) is preferably 50 mol% or more, preferably 80 mol% or more, based on the total amount of the structural units constituting the polyimide. % Or more, more preferably 90 mol% or more, and particularly preferably 95 mol% or more. When the total amount of these is 50 mol% or more, a substrate having the above-mentioned physical properties can be easily obtained, the physical properties can be easily made uniform, and the glass transition temperature can be particularly increased.

A pixel electrode is further arranged on one of these two substrates and a counter electrode is further arranged on the other; or a pixel electrode and a counter electrode are further arranged on one of the two substrates. Further, an alignment film for orienting the liquid crystal material is further arranged on each of these two substrates on which the pixel electrode and the counter electrode can be arranged. The alignment film usually contains polyimide as a main component.

1-2. Joining spacer A joining spacer is arranged between one substrate and another, and is bonded or bonded to at least one of them. As described above, since the liquid crystal element has a bonding spacer bonded or bonded to at least one substrate, the flow of the liquid crystal material when the liquid crystal element is bent is reduced, and the gap (cell gap) between the substrates becomes uneven. It can be suppressed from occurring. The bonding spacer may be a combination of a bonding spacer that is bonded to both one substrate and another substrate, and a bonding spacer that is bonded to only one of the one substrate and the other substrate. Above all, the bonding spacer is preferably adhered to both one substrate and the other substrate in that the cell gap unevenness when the liquid crystal element is bent can be suppressed to a high degree.

The term "adhered or bonded to a substrate" specifically means that, when an alignment film is formed on the substrate, it is bonded or bonded to the alignment film. Whether or not the bonding spacer is adhered or bonded to the substrate (or the alignment film when an alignment film is formed on the substrate) is determined by, for example, even after the liquid crystal element is bent with a radius of curvature of 20 mm and held for 60 minutes. It can be judged by whether or not the adhesive state with the substrate can be maintained without moving the position (without peeling).

The material constituting the bonding spacer is not particularly limited, but is preferably a resin from the viewpoint of having appropriate flexibility and easily following bending. The resin is preferably a cured product of a curable compound. The cured product of the curable compound may be a cured product of a photocurable compound, or a cured product of a thermosetting compound (for example, maleimides such as phenylmaleimide; or a glycidyl group-containing compound such as glycidyl methacrylate). It may be a cured product of a photocurable compound from the viewpoint that a bonding spacer can be formed by light irradiation after laminating two substrates via a layer made of a liquid crystal composition, as will be described later. ..

The photocurable compound for obtaining the bonding spacer is preferably a radically polymerizable compound, and preferably a compound having a radically polymerizable ethylenically unsaturated double bond. The compound having a radically polymerizable ethylenically unsaturated double bond is preferably a compound having a (meth) acryloyl group, and more preferably a (meth) acrylate. The (meth) acryloyl group means an acryloyl group or a meta-acryloyl group. The number of (meth) acryloyl groups contained in one molecule may be one or two or more.

Examples of compounds having one (meth) acryloyl group in the molecule include methyl (meth) acrylate, ethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 4-butyl (meth) acrylate. Includes monofunctional (meth) acrylates such as bicyclohexane and 4-propylcyclohexylbenzene (meth) acrylate.

Examples of compounds having two or more (meth) acryloyl groups in the molecule include triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polytetramethylene glycol di (meth) acrylate, and polyethylene glycol di. PO addition of (meth) acrylate, tripropylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, dimethylol-tricyclodecanedi (meth) acrylate, bisphenol A Bifunctional (meth) acrylates such as di (meth) acrylates; trimethylolpropantri (meth) acrylates, pentaerythritol tri (meth) acrylates, pentaerythritol tetra (meth) acrylates, dipentaerythritol hexa (meth) acrylates, Includes trifunctional or higher functional (meth) acrylates such as ditrimethylol propanetetra (meth) acrylate, glycerin propoxytri (meth) acrylate and pentaerythritol ethoxytetra (meth) acrylate.

Among these, a compound having one or two (meth) acryloyl groups in the molecule is preferable because an unnecessary curing reaction is unlikely to occur. The compound having one or two (meth) acryloyl groups in the molecule may be a liquid crystal compound or a non-liquid crystal compound, but in that good compatibility with the liquid crystal material can be easily obtained. It is preferably a liquid crystal compound. The liquid crystal compound means a compound having a rigid rod-like structure similar to that of a liquid crystal material in the molecule. In the above-mentioned example, 4-butylbicyclohexane (meth) acrylate or 4-propylcyclohexyl (meth) acrylate. Benzene etc. are applicable. Examples of commercially available photocurable compounds include UCL-011 (manufactured by DIC Corporation) and the like.

Although the bonding spacer can be arranged at any position, it is preferably arranged at a position corresponding to the black matrix in terms of not impairing the display characteristics. The plurality of bonding spacers may be arranged randomly or regularly.

The shape of the joining spacer when viewed in a plan view is not particularly limited, and may be any of a dot shape, a line shape, a cross shape, and a grid shape. The dot-shaped shape may be circular, elliptical, or rectangular. The cross shape means a shape in which at least two lines intersect.

1A to 1D are views showing an example of the shape of the bonding spacer. 1A is an example of a dot-shaped (columnar) bonding spacer, FIG. 1B is an example of a line-shaped bonding spacer, FIG. 1C is an example of a cross-shaped bonding spacer, and FIG. 1D is a grid. This is an example of a shaped joint spacer. Above all, the line shape and cloth are easy to confine the liquid crystal material in the region partitioned by the bonding spacer, suppress the flow of the liquid crystal material when the liquid crystal element is bent, and easily keep the adhesion area with the substrate above a certain level. It is preferably in the form of a grid or a grid, and more preferably in a grid. The shape of the cross-shaped intersections and the grid-like corners is not limited to the right-angled shape as shown in FIGS. 1C and 1D, and may be slightly rounded.

FIG. 2A is an explanatory diagram showing an example of a display area partitioned by dot-shaped (columnar) bonding spacers; FIG. 2B is an explanatory diagram showing an example of a display area partitioned by lattice-shaped bonding spacers. .. As shown in FIGS. 2A and 2B, the ratio of the length A of the long side of the display region partitioned by the bonding spacer to the width B of the bonding spacer is the ratio of photocuring in the liquid crystal composition for obtaining the bonding spacer. Although it depends on the content of the sex compound and the shape of the bonding spacer, it is preferable that A: B = 3: 1 to 300: 1. When the ratio of the width B of the bonding spacer to A: B = 3 or more: 1, it is easy to secure a sufficiently display area, so that the emission brightness of the liquid crystal element is not easily impaired. Further, since the binding by the bonding spacer can be sufficiently reduced, the movement of the liquid crystal molecules at the time of voltage switching is less likely to be hindered, and the increase in the driving voltage can be highly suppressed. On the other hand, when A: B = 300 or less: 1, it is easy to secure a sufficient width B of the bonding spacer, so that it is easy to secure a sufficient bonding area between the bonding spacer and the substrate, and the cell gap of the liquid crystal element at the time of bending. It is easy to suppress unevenness to a high degree. Further, when the photocurable compound remaining in the display region is irradiated with light such as ultraviolet rays, it is possible to highly suppress an increase in the driving voltage due to the curing of the photocurable compound. In the case of a lattice-shaped bonding spacer, A: B = 4: 1 to 100: 1 is more preferable, and 8: 1 to 20: 1 is even more preferable. In the case of a columnar bonding spacer, A: B = 4: 1 to 100: 1 is more preferable, and 4: 1 to 20: 1 is even more preferable.

The display area partitioned by the dot-shaped bonding spacers is a region partitioned by a line segment having the minimum distance between adjacent bonding spacers (dotted line portion in FIG. 2A). Further, the width B of the dot-shaped joining spacer may be the long side or the long axis when the dot-shaped joining spacer of FIG. 2A is viewed in a plan view. If the lengths of the long side and the short side or the lengths of the long axis and the short axis are the same, either length may be adopted.

The ratio of the long side A and the short side C of the display area can be long side: short side = 1: 1 to 4: 1. When the ratio of the long side to the short side of the display area is within the above range, sufficient adhesive strength with the substrate can be easily obtained without impairing the display characteristics.

The width of the bonding spacer (width B of the bonding spacer in FIGS. 2A and 2B) can be, for example, 1 to 50 μm, preferably 2 to 30 μm, and more preferably 5 to 20 μm. When the width of the bonding spacer is within the above range, sufficient adhesive strength with the substrate can be easily obtained without impairing the display characteristics.

The average distance between adjacent bonding spacers is preferably 50 to 300 μm. When the average distance between adjacent bonding spacers is 50 μm or more, it is easy to secure a sufficient display area, so that the emission brightness of the liquid crystal element is not easily impaired. Since it is easy to secure a sufficient adhesive area, it is easy to highly suppress cell gap unevenness of the liquid crystal element at the time of bending. The average distance between adjacent bonding spacers is more preferably 80 to 200 μm.

The average distance between adjacent bonding spacers can be obtained by the following procedure.
1) Select any one of the plurality of bonding spacers. Then, the closest joint spacer among the joint spacers adjacent to it is specified, and the minimum distance to the joint spacer is measured. For example, in FIG. 1C, when the joint spacer in the center of the upper stage is an "arbitrarily selected joint spacer" and the joint spacer to the right of the joint spacer is "a joint spacer specified to be in the closest position", the minimum between them. The distance is the distance indicated by D.
2) The operation of 1) above is repeated for all the joining spacers, and the average value thereof is obtained as the average spacing of the joining spacers.

1-3. Liquid crystal layer The liquid crystal layer is a layer containing a liquid crystal material provided in a space partitioned by one substrate, another substrate, and a bonding spacer. The liquid crystal layer is sealed by a sealing member. The liquid crystal layer generates an electric field by applying a voltage between a pair of transparent electrodes provided on at least one of the two substrates, and changes the orientation state of the liquid crystal material. As a result, the transmittance of the liquid crystal layer is changed to display an image.

The liquid crystal material contained in the liquid crystal layer is a liquid crystal material having negative or positive dielectric anisotropy. Examples of liquid crystal materials having negative or positive dielectric anisotropy include nematic liquid crystal materials having negative or positive dielectric anisotropy.

The display mode of the liquid crystal layer may be various display modes such as STN, TN, OCB, HAN, VA (MVA, PVA), IPS, FFS (Fringe Field Switching) and the like. From the viewpoint of widening the viewing angle, the IPS mode or the FFS mode is preferable.

The thickness of the liquid crystal layer is set according to the required contrast ratio and viewing angle. The thickness of the liquid crystal layer may be, for example, 3 to 4 μm, preferably 3 to 3.5 μm, although it depends on the type of the liquid crystal material from the viewpoint of increasing the contrast ratio and the viewing angle.

2. Method for Manufacturing Liquid Crystal Device The method for manufacturing a liquid crystal element of the present invention can be manufactured by any method. In the liquid crystal element, for example, one substrate, another substrate, and a layer composed of a liquid crystal composition arranged between them are laminated, and then the curable compound contained in the liquid crystal composition is cured to form a bonding spacer. It may be obtained through a step of forming a bonding spacer; after forming a bonding spacer on at least one of one substrate and another substrate, the substrates are laminated via a layer made of a liquid crystal composition. You may.

Among them, the liquid crystal element is a single substrate and another in that it is easy to form a bonding spacer that is sufficiently bonded or bonded to both one substrate and another substrate, and that it is easy to form a bonding spacer of an arbitrary shape. It is preferably obtained through a step of laminating a substrate and a layer made of a liquid crystal composition arranged between them, and then curing a curable compound contained in the liquid crystal composition to form a bonding spacer. As described above, the curable compound may be a photocurable compound or a thermosetting compound, but it can be cured in a short time and there is little damage to the liquid crystal material. Is preferable.

That is, a preferable manufacturing method of the liquid crystal element of the present invention is 1) a step of obtaining one substrate coated and formed on one support and another substrate coated and formed on another support, and 2). A laminate having one substrate coated and formed on one support, another substrate coated and formed on another support, and a layer composed of a liquid crystal composition arranged between them is obtained. Step 3) Step of peeling off the other support from the laminate, 4) Irradiating light from at least one surface of the laminate from which the other support has been peeled off in a pattern to form a layer made of a liquid crystal composition. The process includes a step of curing the contained photocurable compound to form a bonding spacer, and 5) a step of peeling one support from the laminate on which the bonding spacer is formed to obtain a liquid crystal element.

3A to 3H are views showing an example of a method for manufacturing a liquid crystal element of the present invention. Hereinafter, each step will be described with reference to the drawings.

Step 1) After applying the composition for a substrate to one support 101 (or another support 201), it is dried and cured if necessary, and all of the above-mentioned (1) to (5) are all. One substrate 103 (or another substrate 203) to be filled is formed (FIGS. 3A-B). As a result, it is possible to obtain a substrate that is less deformed by heat when forming an alignment film or a transparent electrode, which will be described later, even though the thickness is thin.

The one support 101 (or the other support 201) is not particularly limited as long as it has sufficient rigidity to support the one substrate 103 (or the other substrate 203). Examples of such a support include glass plates such as alkaline glass plates and non-alkali glass plates containing _{alkali metal oxides (Na 2} O, K _{2 O); Si wafers; highly rigid polymer films and the like.} ..

The thickness of one support 101 (or the other support 201) is usually 0.05 to 3 mm, preferably 0.1 to 1 mm, and more preferably 0.1 to 0.7 mm. The thicker the support, the more it is possible to suppress the deformation of one substrate 103 (or the other substrate 203) due to heat when forming an alignment film or a transparent electrode, and the thickness of the support is within the above range. By setting it to the inside, it is possible to improve the handleability while suppressing the deformation of the substrate.

When one substrate 103 (or another substrate 203) satisfying all of the above (1) to (5) contains the above-mentioned polyimide, the composition for the substrate includes a diamine component having a specific structure and a specific structure. An amic acid-containing varnish obtained by polymerizing a tetracarboxylic acid dianhydride component having the above in a solvent can be used. Then, the amic acid-containing varnish is applied onto one support 101 (or another support 201) and then imidized to form one substrate 103 (or another substrate 203).

(Preparation of polyamic acid varnish)
First, a diamine having a predetermined structure and a tetracarboxylic acid dianhydride having a specific structure are polymerized in a solvent to obtain an amic acid-containing varnish.

The diamine and tetracarboxylic dianhydride are appropriately selected according to the structure of the polyimide to be prepared. For example, when a substrate containing a polyimide having a structural unit represented by the above general formula (1) is produced, a diamine having an alicyclic hydrocarbon structure or a linear aliphatic diamine and a tetracarboxylic acid containing an aromatic ring are produced. A polyamic acid is prepared by reacting with a diamine. The diamine and the tetracarboxylic dianhydride may be used alone or in combination of two or more.

Examples of diamines having an alicyclic hydrocarbon structure include cyclobutanediamine, cyclohexanediamine, bis (aminomethyl) cyclohexane], diaminobicycloheptane, diaminomethylbicycloheptane (including norbornanediamines such as norbornanediamine), and diaminooxy. Includes bicycloheptane, diaminomethyloxybicycloheptane (including oxanorbornane diamine), isophoronediamine, diaminotricyclodecane, diaminomethyltricyclodecane, bis (aminocyclohexyl) methane, bis (aminocyclohexyl) isopropylidene, etc. ..

Examples of linear aliphatic diamines are 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diamino. Decane, 1,11-diaminoundecane, 1,12-diaminododecane and the like are included.

Examples of tetracarboxylic acid dianhydrides containing an aromatic ring are pyromellitic acid dianhydrides, 3,3', 4,4'-biphenyltetracarboxylic acid dianhydrides, 2,3,3', 4'-. Biphenyltetracarboxylic acid dianhydride, 3,3', 4,4'-benzophenone tetracarboxylic acid dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, 1,4-bis (3,4) -Dicarboxyphenoxy) benzene dianhydride, 2,2-bis [(3,4-dicarboxyphenoxy) phenyl] propane dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) biphenyl dianhydride , Naphthalene 2,3,6,7-tetracarboxylic acid dianhydride, naphthalene 1,2,5,6-tetracarboxylic acid dianhydride, 4,4'-(9-fluorenylidene) bisanhydride, etc. included.

When a substrate containing a polyimide having a structural unit represented by the above general formula (2) is produced, a diamine containing an aromatic ring is reacted with a tetracarboxylic acid dianhydride containing an alicyclic hydrocarbon structure. , Prepare polyamic acid. The diamine and the tetracarboxylic dianhydride may be used alone or in combination of two or more.

Examples of diamines containing an aromatic ring are p-phenylenediamine, m-phenylenediamine, p-xylylene diamine, m-xylylene diamine, which are diamines having one benzene ring; diamines having two benzene rings. Yes, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfone, 4,4'- Diaminodiphenylsulfone, 3,3'-diaminobenzophenone, 4,4'-diaminobenzophenone, 3,3'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 2,2-di (4-aminophenyl) propane, 1 , 5-Diaminonaphthalene ,; 1,3-bis (3-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (3), which are amines having three benzene rings. −Aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminobenzoyl) benzene, 1,3-bis (4-aminobenzoyl) benzene, 1,4-bis (3-Aminobenzoyl) benzene, 1,4-bis (4-aminobenzoyl) benzene, 2,6-bis (3-aminophenoxy) pyridine; 4,4'-bis, a diamine having four benzene rings. (3-Aminophenoxy) biphenyl, 4,4'-bis (4-aminophenoxy) biphenyl, bis [4- (3-aminophenoxy) phenyl] ketone, bis [4- (4-aminophenoxy) phenyl] ketone, Bis [4- (3-aminophenoxy) phenyl] sulfide, bis [4- (4-aminophenoxy) phenyl] sulfide, bis [4- (3-aminophenoxy) phenyl] sulfone, bis [4- (4-aminophenoxy) phenyl] Phenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] ether, bis [4- (4-aminophenoxy) phenyl] ether, 2,2-bis [4- (4-aminophenoxy) phenyl] Includes propane and the like.

Examples of tetracarboxylic acid dianhydrides containing an alicyclic hydrocarbon structure include cyclobutanetetracarboxylic acid dianhydrides, 1,2,3,4-cyclopentanetetracarboxylic acid dianhydrides, 1,2,4. 5-Cyclohexanetetracarboxylic acid dianhydride, bicyclo [2.2.1] heptane-2,3,5,6-tetracarboxylic acid dianhydride, bicyclo [2.2.2. ] Oct-7-en-2,3,5,6-tetracarboxylic acid dianhydride, bicyclo [2.2.2] octane-2,3,5,6-tetracarboxylic acid dianhydride, 2,3 , 5-Tricarboxycyclopentylacetic acid dianhydride, bicyclo [2.2.1] heptane-2,3,5-tricarboxylic acid-6-acetic acid dianhydride, 1-methyl-3-ethylcyclohexa-1-ene -3- (1,2), 5,6-tetracarboxylic acid dianhydride, decahydro-1,4,5,8-dimethanonaphthalene-2,3,6,7-tetracarboxylic acid dianhydride, 4 -(2,5-Dioxo tetrahydrofuran-3-yl) -tetraline-1,2-dicarboxylic acid dianhydride, 3,3', 4,4'-dicyclohexyltetracarboxylic acid dianhydride and the like are included.

Then, the amic acid-containing varnish is applied onto one support 101 (or another support 201), and then dried and heated to be imidized (imide ring closure). As a result, one substrate 103 (or another substrate 203 coated and formed on the other support 201) can be obtained.

The polyamic acid varnish can be obtained, for example, by polymerizing the above diamine and tetracarboxylic acid dianhydride in an aprotic polar solvent or a water-soluble alcohol-based solvent. Examples of aprotonic polar solvents include N-methylpyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, hexamethylphosphoraamide, etc .; ether compounds such as 2-methoxyethanol, 2-ethoxyethanol, 2- (methoxymethoxy) ethoxyethanol, 2-isopropoxyethanol, 2-butoxyethanol, tetrahydrofurfuryl alcohol, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol, tri Ethylene glycol monoethyl ether, tetraethylene glycol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, tripropylene glycol monomethyl ether, polyethylene Glycol, polypropylene glycol, tetrahydrofuran, dioxane, 1,2-dimethoxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether and the like are included. Examples of water-soluble alcohol solvents include methanol, ethanol, 1-propanol, 2-propanol, tert-butyl alcohol, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol. 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 2-butane-1,4-diol, 2-methyl-2,4-pentanediol, 1,2,6-hexane Includes triol, diacetone alcohol and the like.

These solvents can be used alone or in combination of two or more. Among these, N, N-dimethylacetamide, N-methylpyrrolidone or a combination thereof is preferable.

The procedure for preparing the polyamic acid varnish is not particularly limited. For example, prepare a container equipped with a stirrer and a nitrogen introduction pipe. The above-mentioned solvent is put into a nitrogen-substituted container, diamine is added so that the solid content concentration becomes about 30% by weight, and the mixture is stirred and dissolved. To this solution, tetracarboxylic dianhydride is added so that the molar ratio is about 1 with respect to diamine, the temperature is adjusted, and the mixture is stirred for about 1 to 50 hours. This makes it possible to obtain a polyamic acid varnish in which the polyamic acid is dispersed in a solvent.

(Applying and imidizing polyamic acid varnish)
The obtained polyamic acid varnish is applied onto one of the above-mentioned supports 101 (or another support 201) and then heated to imidize the polyamic acid contained in the varnish.

The coating method of the polyamic acid varnish is not particularly limited, and a known coating method can be appropriately selected and used according to a desired coating thickness, viscosity of the resin composition, and the like. Specifically, application methods such as doctor blade knife coater, air knife coater, roll coater, rotary coater, flow coater, die coater, bar coater, spin coat, spray coat, dip coat, etc., screen printing and gravure. Printing techniques such as printing can also be applied.

The imidization of the polyamic acid can be carried out in a normal heating and drying oven. The atmosphere of the drying furnace may be air, inert gas (nitrogen, argon) or the like, but it is preferably an inert gas atmosphere having an oxygen concentration of 5% or less. By lowering the oxygen concentration in the environmental atmosphere, the transparency of the obtained substrate 103 (or other substrate 203) can be increased. Further, the folding resistance and tensile strength of one obtained substrate 103 (or another substrate 203) are likely to be increased. The oxygen concentration of the inert gas in the environmental atmosphere is more preferably 0.1% or less.

The average heating rate during imidization can be in the range of 50 to 300 ° C., for example, 0.25 to 50 ° C./min, preferably 1 to 10 ° C./min, more preferably 2 to 5 ° C./min. be. The rate of temperature rise may be constant or may be changed in two or more steps. When changing to two or more steps, it is preferable that each heating rate is 0.25 to 50 ° C./min. The transparency of the obtained substrate 103 (or the other substrate 203) is increased, and the tensile strength and folding resistance are also increased. Further, the temperature rise may be continuous or stepwise (sequential), but continuous heating causes poor appearance of the obtained substrate 103 (or other substrate 203) and whitening due to the imidization reaction. It is preferable because it can be suppressed. The coating film does not necessarily have to be heated to 300 ° C. When the temperature rise end temperature is less than 300 ° C., the average temperature rise rate in the range from 150 ° C. to the temperature rise end temperature is preferably 0.25 to 50 ° C./min.

The temperature at which the temperature rise ends (maximum reached) is usually preferably a higher temperature, specifically, a temperature higher than the glass transition temperature Tg of polyimide by 10 ° C. or more. By setting the temperature at which the temperature rise ends (maximum reached) to that temperature, it becomes easier to remove the residual solvent contained in the coating film. In addition, the folding resistance of one obtained substrate 103 (or another substrate 203) is increased. The temperature at which the temperature rise ends (maximum reached) is, for example, preferably 200 to 300 ° C, more preferably 250 to 290 ° C, and even more preferably 270 to 290 ° C. The heating time after the temperature rise is completed can be, for example, about 1 second to 10 hours.

A pixel electrode (not shown) is further formed on one of the one substrate 103 and the other substrate 203 thus obtained, and a counter electrode (not shown) is further formed on the other; or only one is opposed to the pixel electrode. Further electrodes (not shown) are formed. The pixel electrode and the counter electrode can be formed by, for example, a vapor deposition method, a sputtering method, or the like.

Further, after forming a coating film of the composition for an alignment film on one substrate 103 and another substrate 203, a rubbing treatment is performed to form an alignment film 105 or 205 (see FIG. 3C). Specifically, as the composition for the alignment film, a solution in which polyimide is dissolved in a solvent is usually used. Therefore, after the composition for an alignment film is applied and dried, it is annealed at a high temperature of about 200 ° C. to form a coating film. Then, the surface of the obtained coating film is subjected to a rubbing treatment. The rubbing process can be performed using, for example, a rubbing roller 106.

One substrate 103 and the other substrate 203 have good heat resistance as described above. Therefore, although the thickness is thin, it is not easily deformed even if it receives the heat of the annealing treatment at the time of forming the alignment film.

About the step 2) From one substrate 103 coated and formed on one support 101, another substrate 203 coated and formed on another support 201, and a liquid crystal composition arranged between them. A laminated body 400 having the layer 301 is obtained (FIGS. 3D to E). The layer 301 made of the liquid crystal composition is sealed by a frame-shaped seal member 303 (a cured product of a seal pattern described later).

The method for producing the laminated body 400 is not particularly limited, but may be either a liquid crystal injection method or a liquid crystal dropping method.

The method for manufacturing the laminated body 400 by the liquid crystal injection method is, for example, a step of applying a sealant in a frame shape to a substrate 103 of 2A-1) to form a seal pattern having an opening, 2A-2) a seal pattern. Is surrounded by a step of superimposing one substrate 103 and another substrate 203 on the other substrate 203 in an uncured state via a seal pattern, 2A-3) a process of curing the seal pattern, and 2A-4) a seal pattern between the substrates. This includes a step of closing the sealing port after injecting the liquid crystal composition into the region.

In the step 2A-3), curing by heating may be performed. As a result, the sealant can be sufficiently cured in a short time, and one substrate 103 and the other substrate 203 can be adhered to each other.

The method for manufacturing the laminate 400 by the liquid crystal dropping method is, for example, a step of applying a sealant in a frame shape to a substrate 103 of 2B-1) to form a seal pattern, and 2B-2) a state in which the seal pattern is uncured. In the step of dropping the liquid crystal composition onto the region surrounded by the seal pattern of one substrate 103 or the region of another substrate 203 facing the region surrounded by the seal pattern, 2B-3) one substrate 103. It includes a step of superimposing and another substrate 203 on the seal pattern via a seal pattern, and 2B-4) a step of curing the seal pattern.

In the step 2B-2), the state in which the seal pattern is uncured means a state in which the curing reaction of the sealant has not progressed to the gel point. Therefore, in the step 2B-2), the seal pattern may be semi-cured by irradiating or heating the seal pattern in order to suppress the dissolution of the sealant in the liquid crystal display.

In the step 2B-4), only curing by light irradiation may be performed, but curing by heating may be performed after curing by light irradiation. By curing by light irradiation, the sealant can be cured in a short time, so that dissolution in the liquid crystal display can be suppressed. By combining curing by light irradiation and curing by heating, damage to the liquid crystal layer due to light can be reduced as compared with the case where only curing by light irradiation is performed.

The light to be irradiated is preferably light having a wavelength of 350 to 450 nm. This is because light having the above wavelength causes relatively little damage to the liquid crystal material and the driving electrode. For the irradiation of light, a known light source that emits ultraviolet rays or visible light can be used. When irradiating visible light, a high-pressure mercury lamp, a low-pressure mercury lamp, a metal halide lamp, a xenon lamp, a fluorescent lamp, or the like can be used.

The liquid crystal composition used includes a liquid crystal material, a photocurable compound, and a photopolymerization initiator. The liquid crystal material is the same as the liquid crystal material contained in the liquid crystal layer described above; the photocurable compound is the same as the photocurable compound for obtaining the bonding spacer described above.

The content of the photocurable compound in the liquid crystal composition may be 10 to 35% by mass, preferably 15 to 30% by mass, based on the total mass of the liquid crystal composition. When the content of the photocurable compound is 10% by mass or more, it is easy to obtain a bonding spacer having sufficient adhesive strength in a short time by light irradiation, and when it is 35% by mass or less, the photocuring remaining in the display region is obtained. It is easy to suppress the deterioration of the display characteristics due to the increase in the driving voltage with the curing of the sex compound.

The photopolymerization initiator is preferably a photoradical polymerization initiator. Examples of photoradical polymerization initiators include cleavage type radical initiators and hydrogen abstraction type radical initiators.

Examples of cleaved radical initiators include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyl dimethyl ketal, 1- (4-isopropylphenyl) -2-hydroxy-2-. Methylpropan-1-one, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexyl-phenylketone, 2-methyl-2-morpholino (4-thiomethylphenyl) Acetphenone-based initiators, including propane-1-one and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone, 2,2-dimethoxy-2-phenylacetophenone, benzoin, benzoin methyl ether and Includes benzoin-based initiators, including benzoin isopropyl ether, acylphosphenyl oxide-based initiators, including 2,4,6-trimethylbenzoindiphenylphosphine oxide, benzyl and methylphenylglioxyesters.

Examples of hydrogen abstraction type radical initiators include benzophenone, methyl-4-phenylbenzophenone o-benzoyl benzoate, 4,4'-dichlorobenzophenone, hydroxybenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, acrylicization. Benzophenone-based initiators, including benzophenone, 3,3', 4,4'-tetra (t-butylperoxycarbonyl) benzophenone and 3,3'-dimethyl-4-methoxybenzophenone, 2-isopropylthioxanthone, 2,4- Thioxanthone-based initiators containing dimethylthioxanthone, 2,4-diethylthioxanthone and 2,4-dichlorothioxanthone, aminobenzophenone-based initiators containing Michler ketone and 4,4'-diethylaminobenzophenone, 10-butyl-2-chloroacry Includes dong, 2-ethylanthraquinone, 9,10-phenanthrene quinone and campharquinone.

The content of the photopolymerization initiator in the liquid crystal composition is preferably 0.1 to 30% by mass, more preferably 0.5 to 10% by mass, based on the total mass of the photocurable compound. It is more preferably 1 to 5% by mass.

Regarding the step 3), the other support 201 is peeled off from the laminated body 400 (FIG. 3E). Specifically, the other support 201 may be peeled off from the laminate 400, or the other laminate portion may be peeled off from the other support 201. The method of peeling off is not particularly limited, but the laser lift-off method can be preferably adopted from the viewpoint that the laminate obtained after peeling can be easily peeled off without damaging it. In the laser lift-off method, by irradiating a pulse laser, for example, a chemical bond between a substrate containing polyimide and a support such as a glass plate can be broken and peeled off.

About the step 4) Light is irradiated from at least one surface of the laminated body 400 obtained by peeling off the other support 201 in a pattern, and the photocurable compound contained in the liquid crystal composition is cured and bonded. The spacer 305 is formed (FIGS. 3F to G).

The method of irradiating light in a pattern is not particularly limited, and examples thereof include a method of applying a photomask 307 provided in a pattern on another substrate 203 and irradiating light from above. For example, by irradiating the light through the photomask 307 provided with the grid-like slits, the light can be irradiated in a grid pattern, so that the grid-like bonding spacer 305 can be formed. Then, the layer 301 made of the liquid crystal composition partitioned by the bonding spacer 305 becomes a liquid crystal layer.

The light to be irradiated is preferably light having a wavelength of 350 to 450 nm, as in the step of 2B-4) described above. This is because light of the above wavelength causes relatively little damage to the liquid crystal material and the driving electrode. For the irradiation of light, a known light source that emits ultraviolet rays or visible light can be used.

The light irradiation intensity and the light irradiation time may be such that the photocurable compound can be sufficiently cured. Light irradiation intensity is, for example 0.5~10mW / cm ^2, preferably from 1 mW / cm ^2. The light irradiation time is, for example, 300 to 3600 seconds, preferably 1800 to 3600 seconds.

About the step 5) One support 101 is peeled off from the obtained laminate 400 to obtain a liquid crystal element 500 (FIGS. 3G to H). When one support 101 is peeled off from the laminate 400, the rest of the laminate is large and easily curved (easily bent). However, in the present invention, since the bonding spacer 305 is adhered or bonded to at least one substrate, there is little deformation of the substrates 103 and 203 between the adjacent bonding spacers 305 in the remaining portion of the curved laminate, and the liquid crystal display. The flow of material can also be suppressed. As a result, the distance between one substrate 103 and the other substrate 203 can be easily kept constant, and cell gap unevenness can be suppressed. In FIG. 3H, the end portion where one substrate 103 and the other substrate 203 do not face each other is an unnecessary portion and is finally cut off.

Further, in the obtained liquid crystal element 500, the bonding spacer 305 is sufficiently adhered or bonded even if it is greatly bent during use. As a result, even if the liquid crystal element 500 is greatly bent during use, cell gap unevenness can be suppressed, so that display unevenness can be suppressed.

In FIGS. 3A to 3H, one substrate and another substrate are laminated via a layer made of a liquid crystal composition, and then the curable compound contained in the liquid crystal composition is cured to form a bonding spacer. An example is shown, but the present invention is not limited to this, and as described above, after forming a bonding spacer on one substrate, another substrate may be laminated via a layer made of a liquid crystal composition. In this method, the liquid crystal composition may contain a liquid crystal material and does not contain a curable compound or a polymerization initiator. Further, the spacer forming composition for forming the bonding spacer contains a curable compound and a polymerization initiator. As the curable compound, the same compound as the photocurable compound or thermosetting compound for obtaining the above-mentioned bonding spacer can be used. Examples of commercially available spacer-forming compositions include PR200 (manufactured by Osaka Organic Chemical Co., Ltd.) and the like.

Hereinafter, the present invention will be described with reference to examples. By way of examples, the scope of the invention is not construed as limiting.

1. 1. Substrate manufacturing / evaluation (board manufacturing)
5.71 g (0.05 mol) of 1,4-diaminocyclohexane (CHDA), 1,4-bis (amino) in a 300 mL 5-neck separable flask equipped with a thermometer, stirrer, nitrogen introduction tube, and dropping funnel. 7.11 g (0.05 mol) of methyl) cyclohexane (14BAC) and 229.7 g of N, N-dimethylacetamide (DMAc) were added and stirred.
30.9 g (0.1 mol) of bis (3,4-dicarboxyphenyl) ether dianhydride (ODPA) was charged therein, and the reaction vessel was bathed in an oil bath maintained at 120 ° C. for 5 minutes. , It was confirmed that it was rapidly redissolved. After removing the oil bath, the mixture was further stirred at room temperature for 18 hours to obtain a polyamic acid varnish containing polyamic acid.
The polyamic acid varnish was dropped onto a washed glass plate (support) having a thickness of 0.7 mm and spin-coated. The conditions for spin coating were 2500 rpm for 30 seconds. Then, the glass plate coated with the polyamic acid varnish was heated to 270 ° C. at a heating rate of 2 ° C./min in an inert oven and fired at 270 ° C. for 2 hours. As a result, a polyimide substrate having a thickness of 10 μm was formed on the glass plate.

(Evaluation of board)
^{(1) L *} a * ^{b *} and ^{b *} values in ^{b *} values obtained polyimide substrate ^L * ^a * ^{b *} color system in the color system, using a Suga Test Instruments Ltd. Color Cute i-type, transmission mode After calibrating with a white standard plate by the photometric method 8 ° di, the measurement was performed.

(2) Rth
The in-plane refractive index nz of the obtained polyimide substrate, the refractive index ny in the Y-axis direction orthogonal to it, and the refractive index nz in the Z-axis direction (thickness direction) are inspected by Otsuka Denshi Co., Ltd. It was measured with light at room temperature (20 to 25 ° C.) and a wavelength of 550 nm with an apparatus (model RETS-100). Then, the phase difference (Rth) in the thickness direction was calculated from the refractive indexes nx, ny, nz and the thickness (d) of the polyimide substrate based on the following formula.
Rth (nm) = [(nx + ny) /2-nz] × d

(3) MIT Folding Resistance The obtained polyimide substrate was cut into a shape having a length of about 120 mm and a width of 15 mm to prepare a test piece. When this test piece was bent under the following conditions, the number of times until it broke was measured.
Specifically, using a MIT folding resistance tester (manufactured by Yasuda Seiki Seisakusho, type 307), after fixing one end of the test piece, the other end is grasped and the test piece is reciprocally bent to form the test piece. The number of bends before breaking was measured. The measurement conditions were as follows.
(Measurement condition)
Bending radius: R = 0.38 mm
Load: 0.5kgf
Bending angle: 270 ° (135 ° left and right)
Bending speed: 175 times / min Number of tests: n = 3
At the time of the test, bending to one side of the test piece was counted as one time. The test was performed three times, and the arithmetic mean value of the three test results was rounded to the nearest double digit as the measurement result of folding resistance. The upper limit of the folding resistance measurement result was set to 1 million times.

(4) Glass transition temperature (Tg)
The obtained polyimide substrate was cut into a width of 4 mm and a length of 20 mm to obtain a test piece. The glass transition temperature of this test piece was measured using a thermal analyzer (TMA-50) manufactured by Shimadzu Corporation.
TMA measurement was performed in the temperature range of 25 to 350 ° C. under the measurement conditions of a heating rate of 5 ° C./min, a load of 14 g / mm ² , and a tension mode. The transition temperature (Tg) was determined.

(5) Maximum Transmittance The light transmittance of the obtained polyimide substrate at a wavelength of 365 ± 5 nm was measured with a spectrophotometer (MultiSpec-1500) manufactured by Shimadzu Corporation. Then, the maximum transmittance at a wavelength of 365 ± 5 nm at a thickness of 10 μm was calculated.

The physical characteristics of the obtained polyimide substrate are shown in Table 1.

2. Fabrication / Evaluation of Liquid Crystal Element [Example 1]
(Formation of polyimide substrate)
Two glass plates (support plates) having a thickness of 0.7 mm were prepared. A polyimide substrate having a thickness of 10 μm was formed on each of these glass plates in the same manner as in the above-mentioned (preparation of the substrate) (step 1 above).

A polyimide solution for alignment film AL1254 (manufactured by JSR Corporation) was applied onto each of the obtained polyimide substrates, dried, and then heat-cured at 200 ° C. to further form a coating film having a thickness of 0.1 μm. The surface of the obtained coating film was further subjected to a rubbing treatment to form an alignment film. The rubbing treatment was performed so that the rubbing directions of the coating films on the upper and lower polyimide substrates were orthogonal to each other, and the injected liquid crystal molecules were twisted and oriented.

(Formation of laminate)
Of the two glass plates on which the polyimide substrate and the alignment film are laminated, the photocurable sealant 3035B (manufactured by ThreeBond Co., Ltd.) is placed on the alignment film of one of the glass plates in a frame shape (the size of the area inside the frame shape is After applying to 2.5 cm × 2.5 cm), it was dried. Next, inside the frame-shaped sealant, TD1016L (manufactured by JNC) as a liquid crystal material, UCL-011 (manufactured by DIC, ultraviolet curable liquid crystal monomer) as a photocurable compound, and as a photopolymerization initiator. After dropping the liquid crystal composition containing 2,2-dimethoxy-2-phenylacetophenone (manufactured by DIC), a layer composed of the liquid crystal composition was formed. The content of the ultraviolet curable liquid crystal monomer in the liquid crystal composition was 30% by mass.
Then, one glass plate on which the polyimide substrate and the alignment film are laminated and the other glass plate on which the polyimide substrate and the alignment film are laminated are arranged, and the alignment film of the one glass plate and the other glass plate are oriented. After the films are bonded so as to face each other via a layer made of a liquid crystal composition, the sealant is cured by irradiating with ultraviolet rays at 100 mW for 300 seconds to cure the laminate (one glass plate / one polyimide substrate /). A layer composed of an alignment film / liquid crystal composition / an alignment film / a laminate having a laminated structure of the other polyimide substrate / the other glass plate) was obtained (step 2) described above. The thickness of the layer made of the liquid crystal composition in the laminated body was 5 μm.

The other glass plate was peeled off from the obtained laminate by a laser lift-off method (step 3) described above).

(Formation of joint spacer)
Then, the surface of the other exposed polyimide substrate was irradiated with ultraviolet light in a grid pattern through a photomask, and the photocurable compound UCL-011 (manufactured by DIC) was photocured. The irradiation of ultraviolet light was performed with an irradiation intensity of 1 mW / cm ² and an irradiation time of 3600 seconds. As a result, a bonding spacer was formed in a grid pattern and adhered (bonded) to both the alignment film on one substrate and the alignment film on the other substrate (step 4 above). In the lattice-shaped joining spacer, the long side A of the display area was 100 μm, the short side C was 100 μm, and the width B of the joining spacer was 10 μm (long side A of the display area: width B of the joining spacer B = 10: 1). ..

(Peeling of glass plate)
One glass plate was peeled off from the laminate on which the bonding spacer was formed by a laser lift-off method to obtain a liquid crystal element 1 (step 5 above).

[Example 2]
(Formation of polyimide substrate)
In the same manner as in Example 1, two glass plates in which the polyimide substrate and the alignment film were laminated in this order were prepared.

(Formation of joint spacer)
Of the two glass plates in which the polyimide substrate and the alignment film are laminated in this order, PR200 (Osaka Organic Chemical Co., Ltd.) is used as a thermosetting compound on the alignment film of one of the polyimide substrates formed on one glass plate. The spacer composition made of (manufactured by) was applied, irradiated with ultraviolet rays at 60 mW for 1 minute through a photomask, and then developed with an alkaline aqueous solution. Then, it was fired at 150 ° C. for 30 minutes to form a bonding spacer which was lattice-shaped and bonded to one of the polyimide substrates. In the lattice-shaped joining spacer, the long side A of the display area was 100 μm, the short side C was 100 μm, and the width B of the joining spacer was 10 μm (long side A of the display area: width B of the joining spacer B = 10: 1). ..

(Formation of laminate)
A photocurable sealant 3035B (manufactured by ThreeBond Co., Ltd.) was applied in a frame shape to the peripheral edge of the alignment film to which the spacer composition was applied, and then dried. Then, a liquid crystal composition containing TD1016L (manufactured by JNC Corporation) as a liquid crystal material is dropped inside the frame-shaped sealant (the size of the region inside the frame is 2.5 cm × 2.5 cm), and then the liquid crystal composition is dropped. A layer made of a liquid crystal composition was formed.
Then, one glass plate on which the polyimide substrate, the alignment film, and the layer composed of the liquid crystal composition are laminated, and the other glass plate on which the polyimide substrate and the alignment film are laminated are formed on the alignment film of the one glass plate. After the alignment film of the other glass plate and the alignment film of the other glass plate were bonded so as to face each other via a layer made of the liquid crystal composition, the sealant was cured by irradiating with ultraviolet rays at 100 mW for 300 seconds to obtain a laminate. The thickness of the liquid crystal layer in the laminated body was 5 μm.

(Peeling of glass plate)
One glass plate and the other glass plate were peeled off from the obtained laminate by a laser lift-off method, respectively, to obtain a liquid crystal element 2.

[Comparative Example 1]
(Formation of polyimide substrate)
In the same manner as in Example 1, two glass plates in which the polyimide substrate and the alignment film were laminated in this order were prepared.

(Formation of spacer)
Of the two glass plates in which the polyimide substrate and the alignment film are laminated in this order, spherical fine particles (micropearl manufactured by Sekisui Chemical Co., Ltd., diameter 5 μm) are directly placed on the alignment film of one glass plate with an air gun. It was sprayed to form a spacer. The spray amount was 0.3 to 0.4 mg.

(Formation of laminate)
A photocurable sealant 3035B (manufactured by ThreeBond Co., Ltd.) was applied in a frame shape to the peripheral edge of the alignment film on which the spacer was formed, and then dried. Then, a liquid crystal composition containing TD1016L (manufactured by JNC Corporation) as a liquid crystal material is dropped inside the frame-shaped sealant (the size of the region inside the frame is 2.5 cm × 2.5 cm), and then the liquid crystal composition is dropped. A layer made of a liquid crystal composition was formed.
Next, one glass plate on which the polyimide substrate, the alignment film, and the layer composed of the liquid crystal composition are laminated, and the other glass plate on which the polyimide substrate and the alignment film are laminated are formed on the alignment film of the one glass plate. After the alignment film of the other glass plate and the alignment film of the other glass plate were bonded so as to face each other via a layer made of the liquid crystal composition, the sealant was cured by irradiating with ultraviolet rays at 100 mW for 300 seconds to obtain a laminate. The thickness of the liquid crystal layer in the laminated body was 5 μm.

(Peeling of glass plate)
One glass plate and the other glass plate were peeled off from the obtained laminate by a laser lift-off method, respectively, to obtain a liquid crystal element 3.

When the obtained liquid crystal elements 1 to 3 were curved under predetermined conditions, the presence or absence of display unevenness (brightness unevenness) due to the disorder of the orientation of the liquid crystal was evaluated by the following method.

(Display unevenness)
Visually observe the display unevenness in the process of bending the obtained liquid crystal element from the flat state to the curved state where the radius of curvature R becomes 20 mm, and the display unevenness (brightness unevenness) when the obtained liquid crystal element is fixed in the curved state. It was evaluated according to the following criteria.
⊚: Even in the process of bending (from a flat state in which the liquid crystal is not curved to a state in which a force is applied to the liquid crystal device and the liquid crystal device is continuously pressed until the specified radius of curvature R is reached), the orientation of the liquid crystal is not disturbed and the brightness is increased. There was no change and no display unevenness occurred.
◯: In the process of bending, the orientation of the liquid crystal was disturbed, the brightness changed, and display unevenness occurred. After that, when it was fixed in the state of the specified radius of curvature R, the disturbance of the liquid crystal settled down within a few seconds, and no display unevenness was confirmed.
X: In the process of bending, the orientation of the liquid crystal was disturbed, the brightness changed, and display unevenness occurred. After that, even if it was fixed in the state of the specified radius of curvature R, the orientation of the liquid crystal was disturbed and the brightness changed, and it did not change from the state in which the display unevenness occurred.

The results obtained are shown in Table 2.

As shown in Table 2, the liquid crystal elements of Examples 1 and 2 having a spacer bonded to at least one of one substrate and the other substrate cause display unevenness in both the bending process and the state of being fixed in the bending state. It turns out that it can be suppressed.

In particular, it can be seen that the liquid crystal element of Example 1 having a spacer bonded to both one substrate and the other substrate can highly suppress display unevenness in either the bending process or the state in which the bending state is fixed.

On the other hand, the liquid crystal element of Comparative Example 1 having a particle spacer that is not bonded to either one substrate or the other substrate cannot suppress display unevenness in either the bending process or the state of being fixed in the curved state. You can see that. It is considered that this is because the particle spacer moves at the time of bending, so that the liquid crystal material flows (cell gap unevenness occurs) and the orientation unevenness of the liquid crystal material occurs.

[Examples 3 to 6]
In Example 1 (Formation of Joining Spacer), the long side A, the short side C, and the width B of the joining spacer of the display area of the lattice-shaped joining spacer were changed as shown in Table 3, respectively. Liquid crystal elements 4 to 7 were obtained in the same manner as in 1.

[Examples 7 to 10]
Same as Example 1 except that the shape of the joining spacer is changed to a columnar shape (dot shape), and the long side A, the short side C, and the width B of the joining spacer of the display area are changed as shown in Table 4, respectively. The liquid crystal elements 8 to 11 were obtained.

Then, the presence or absence of display unevenness (unevenness of brightness) due to the disorder of the orientation of the liquid crystal when the obtained liquid crystal elements 4 to 11 were curved was evaluated in the same manner as in Example 1. Further, for the liquid crystal elements 4 to 7, the drive voltage was further evaluated by the following method.

(Drive voltage)
The obtained liquid crystal element was placed between two polarizing plates arranged so that the absorption axes were orthogonal to each other. Then, an AC voltage (square wave) of 1 kHz was applied to the liquid crystal element, and the change in transmitted light intensity was measured. The liquid crystal element sandwiched between the two polarizing plates has a maximum transmittance when the applied voltage is 0 V, and the transmittance decreases as the applied voltage increases. The voltage that minimizes the transmittance is defined as the drive voltage.
◯: Drive voltage is 10 V or less Δ: Drive voltage is more than 10 V and 20 V or less ×: Drive voltage is 20 V or more

The results of Examples 3 to 6 are shown in Table 3; the results of Examples 7 to 10 are shown in Table 4.

As shown in Table 3, when the bonding spacer is in a grid pattern and the concentration of the photocurable compound in the liquid crystal composition is 30% by mass, the display unevenness at the time of curvature depends on the ratio of A: B. However, it can be seen that the radius of curvature can be highly suppressed regardless of whether the radius of curvature is 20 mm or more or less than 20 mm.
On the other hand, regarding the drive voltage, it can be seen that the increase in the drive voltage can be particularly suppressed by setting the ratio of A: B between 6: 1 and 50: 1, for example, 8: 1 to 20: 1. This is considered to be due to the following reasons. That is, when the ratio of A is a certain value or more, the binding by the bonding spacer is not too large, so that the liquid crystal molecules are likely to move at the time of voltage switching, and the increase in the driving voltage is likely to be highly suppressed. Further, when the ratio of A is not a certain value or less, the amount of the uncured photocurable compound remaining in the display region is not too large, so that when the display region is exposed to ultraviolet rays, the photocurable compound is cured. The formation of the accompanying polymer network can be highly suppressed, and the rise in drive voltage is likely to be highly suppressed.

As shown in Table 4, when the bonding spacer is columnar (dot-shaped) and the concentration of the photocurable compound in the liquid crystal composition is 30% by mass, the ratio of A: B is 50 or less: 1, for example. It can be seen that the display unevenness at the time of bending can be particularly suppressed by setting the ratio to 4: 1 to 20: 1. This is because, in the columnar bonding spacer, when the ratio of A: B is 4: 1 to 20: 1, it is easy to obtain sufficient adhesive strength between the bonding spacer and the substrate, and the cell gap unevenness at the time of bending is high. It is considered that this is because it is reduced to.

According to the present invention, it is possible to provide a liquid crystal element having high heat resistance, suppressing cell gap unevenness at the time of bending, and having excellent bending resistance, and a method for manufacturing the same.

101 One support 103 One substrate 105 Alignment film 201 Other support 203 Other substrate 205 Alignment film 301 Layer made of liquid crystal composition 303 Sealing member 305 Bonding spacer 400 Laminated body 500 Liquid crystal element

Claims (9)

A bond placed between one substrate, another substrate facing the substrate, the one substrate and the other substrate, and directly bonded to an alignment film on at least one of the one substrate and the other substrate. It has a spacer, the one substrate, the other substrate, and a liquid crystal layer filled in a space partitioned by the bonding spacer.
The bonding spacer is a cured product of a liquid crystal composition containing a liquid crystal material, an ultraviolet curable liquid crystal monomer, and a photopolymerization initiator.
The content of the ultraviolet curable liquid crystal monomer is 10 to 35% by mass with respect to the liquid crystal composition.
The one substrate and the other substrate contain a polyimide having a structural unit represented by the following general formula (1) or a structural unit represented by the following general formula (2), and the following (1) to (5). ) Satisfy all
Liquid crystal element.
(1) The L ^* a ^* b ^* color system b ^* value at a thickness of 10 μm is 5 or less. (2) The phase difference value Rth in the thickness direction at a wavelength of 550 nm at a thickness of 10 μm is 200 nm or less. 3) The number of fold resistance in the MIT fold resistance test at a thickness of 10 μm measured according to JIS P8115 is 10,000 or more. (4) The glass transition temperature is 200 ° C or more. (5) Thickness Is 50 μm or less

(In the general formula (1)
R ₁ represents a divalent group having 4 to 15 carbon atoms or a divalent linear aliphatic group having 5 to 12 carbon atoms including an alicyclic hydrocarbon structure.
Y ₁ represents a tetravalent group having 6 to 27 carbon atoms including an aromatic ring)

(In the general formula (2)
R ₂ represents a divalent group having 6 to 27 carbon atoms including an aromatic ring.
Y ₂ represents a tetravalent group having 4 to 12 carbon atoms including an alicyclic hydrocarbon structure) The bonding spacer is directly bonded to both the alignment film on the one substrate and the alignment film on the other substrate.
The liquid crystal element according to claim 1. The UV curable liquid crystal monomer is a monofunctional (meth) acrylate.
The liquid crystal element according to claim 1 or 2. The one substrate and the other substrate further satisfy the following (6).
The liquid crystal element according to any one of claims 1 to 3.
(6) The maximum transmittance at a wavelength of 365 ± 5 nm at a thickness of 10 μm is 15% or more. The shape of the joining spacer when viewed in a plan view is a line shape, a cross shape, or a grid shape.
The liquid crystal element according to any one of claims 1 to 4. The shape of the joint spacer when viewed in a plan view is a grid pattern.
The liquid crystal element according to claim 5. The ratio of the length A of the long side of the display region partitioned by the lattice-shaped joining spacers to the width B of the joining spacers is A: B = 3: 1 to 300: 1.
The liquid crystal element according to claim 6. The average distance between adjacent bonding spacers is 50 to 300 μm.
The liquid crystal element according to any one of claims 1 to 7. A polyimide formed by coating on one support and having a structural unit represented by the following general formula (1) or a structural unit represented by the following general formula (2), and the following (1) to (6) A substrate containing all of the above, a polyimide formed by coating on another support, and having a structural unit represented by the following general formula (1) or a structural unit represented by the following general formula (2), and The process of obtaining another substrate that satisfies all of the following (1) to (6), and
(1) L ^* a ^* b ^* color system b ^* value at a thickness of 10 μm is 5 or less (2) Rth at a wavelength of 550 nm at a thickness of 10 μm is 150 nm or less (3) Compliant with JIS P8115 The number of fold resistance in the MIT fold resistance test at a thickness of 10 μm is 10,000 or more (4) The glass transition temperature is 200 ° C or more (5) The thickness is 50 μm or less (6) ) The one substrate coated and formed on the one support having a maximum transmittance of 15% or more at a wavelength of 365 ± 5 nm at a thickness of 10 μm, and the other substrate coated and formed on the other support. A step of obtaining a laminate having a substrate, a layer composed of a liquid crystal material, a photocurable compound, and a liquid crystal composition containing a photopolymerization initiator, which is arranged between the one substrate and the other substrate. ,
The step of peeling off the other support from the laminated body and
Light is radiated in a pattern from at least one surface of the laminate from which the other support has been peeled off to cure the photocurable compound, and at least one of the one substrate and the other substrate is cured. The process of forming a joint spacer to be joined with
A step of peeling off the one support from the laminated body on which the bonding spacer is formed to obtain a liquid crystal element is included.
A method for manufacturing a liquid crystal element.

(In the general formula (1)
R ₁ represents a divalent group having 4 to 15 carbon atoms or a divalent linear aliphatic group having 5 to 12 carbon atoms including an alicyclic hydrocarbon structure.
Y ₁ represents a tetravalent group having 6 to 27 carbon atoms including an aromatic ring)

(In the general formula (2)
R ₂ represents a divalent group having 6 to 27 carbon atoms including an aromatic ring.
Y ₂ represents a tetravalent group having 4 to 12 carbon atoms including an alicyclic hydrocarbon structure)

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