TW202344907A - Weak-anchoring liquid crystal aligning agent, and liquid crystal display element - Google Patents

Abstract

This weak-anchoring liquid crystal aligning agent is used to form a liquid crystal alignment film of a liquid crystal cell having liquid crystals and the liquid crystal alignment film, and comprises: a polymer having a structural unit represented by formula (1) and a component exhibiting a weak-anchoring property. (In formula (1), R1 and R2 each independently represent a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 3 carbon atoms, and X represents -O-Ra, -N(Ra)(Rb), or -S-Ra (Ra represents a hydrogen atom or a monovalent organic group, and Rb represents a monovalent group).

Description

Weakly anchored liquid crystal alignment agents and liquid crystal display components

The present invention relates to an organic film exhibiting weak anchoring properties (weak anchoring film) that can be manufactured at low cost and without complicated steps, and can be used to realize higher brightness and low-voltage driven liquid crystal display elements, and can utilize Alignment agents and polymers in liquid crystals are weakly anchored in them.

In recent years, liquid crystal display elements have been widely used in mobile phone, computer and television monitors. Liquid crystal display elements have the characteristics of thinness, light weight, and low power consumption, and are expected to be used in more aspects such as VR (Virtual Reality) and ultra-high-definition displays in the future. Various display methods have been proposed for LCD display methods, such as TN (Twisted Nematic) method, IPS (In-Plane Switching) method, VA (Vertical Alignment) method, etc. All display methods Both use a film (liquid crystal alignment film) that induces liquid crystal into a desired alignment state.

Especially for products equipped with touch panels such as tablets, smartphones, and smart TVs, it is ideal to use the IPS method, which is not easily disturbed even if the display is touched. In recent years, in order to improve contrast and viewing angle characteristics, FFS ( Frindge Field Switching (Frindge Field Switching) liquid crystal display elements and liquid crystal alignment technology using the optical alignment method have been adopted.

However, compared with the IPS method, the FFS method has problems such as higher substrate manufacturing costs and the occurrence of a unique display failure called Vcom shift. In addition, the optical alignment method has advantages over the rubbing alignment method in that it can easily adapt to the expansion of devices and can significantly improve display characteristics. On the other hand, there are some theoretical issues (if photodegradable materials are used). , examples include display defects due to decomposition products, and if it is a photoisomerization type, examples include imprinting due to insufficient alignment force, etc.). In order to solve these problems, liquid crystal display element manufacturers and liquid crystal alignment film manufacturers are currently making various efforts.

On the other hand, in recent years, some people have proposed a weak anchor IPS method that uses weak anchor technology. Compared with the conventional IPS method, this method can achieve improved contrast ratio and significantly lower voltage driving (see Patent Document 1).

The weakly anchored IPS method uses a liquid crystal alignment film with strong anchoring energy on one side of the substrate, and uses a film that has been treated without anchoring energy on the other side of the substrate (with an electrode that generates a transverse electric field). to make.

In recent years, someone has proposed a technology to create a weakly anchored IPS method by directly placing a thick polymer brush on the substrate (see Patent Document 2). Through this technology, the contrast ratio has been greatly improved and the driving voltage has been significantly reduced.

In addition, as another method, it has been proposed to use a liquid crystal alignment film that can generate photofree radicals and a free radical polymerizable compound to irradiate UV in the liquid crystal and cause it to undergo a free radical reaction, thereby weakening it. The technology of anchoring weakly anchored IPS method (refer to Patent Document 3). With this technology, improvements in contrast ratio, substantial low-voltage driving, high-speed response, and reduction in burn-in have been achieved using methods that can be mass-produced. [Prior technical literature] [Patent Document]

[Patent Document 1] Japanese Patent No. 4053530 [Patent Document 2] Japanese Patent Application Publication No. 2013-231757 [Patent Document 3] International Publication No. 2019/004433 Pamphlet

[Problem to be solved by the invention]

The method of directly placing a thick polymer brush on the substrate (Patent Document 2) requires a surface treatment step of setting a reaction point on the substrate and a step of depositing the polymer from the reaction point on the substrate surface, so it is considered to complicate the steps. Furthermore, considering the fact that a high degree of deoxidation conditions are required and the environment must be precisely controlled, the technology is highly difficult and is not practical for mass production.

In order to solve the above problems, some people have also proposed a method of obtaining weakly anchored IPS display elements by coating bottlebrush polymers with fixed parts on the substrate. However, in order to manufacture bottlebrush polymers, living radical polymerization needs to be used. There will be a problem that it is not easy to supply in large quantities. In addition, bottlebrush polymers lack solvent selectivity and have low solubility in N-methyl-2-pyrrolidone (NMP), γ-butyrolactone (GBL), etc., which have been frequently used in the past. There will be big problems.

In order to obtain weak anchorage, it is necessary to achieve complete infiltration of the liquid crystal and polymer layers at the interface of the weakly anchored liquid crystal alignment film, and the material design needs to be low Tg and low polarity. Therefore, it is difficult to increase the viscosity of the material. If a coating method such as printing coating is used that requires a certain viscosity, problems such as deterioration of the uniformity of the coating area and film thickness are thought to occur.

It is thought that in the method of weak anchoring using photoradical polymerization and radically polymerizable compounds (Patent Document 3), the polymerizable additives may volatilize in the high vacuum state when liquid crystal is injected, or may be caused by There are issues such as the step of irradiating ultraviolet rays after the production of liquid crystal elements, which may have adverse effects on the liquid crystal composition.

If such technical issues can be solved, panel manufacturers can easily and efficiently produce weakly anchored IPS liquid crystal display elements with advantages such as battery saving and image quality improvement.

The present invention was made in order to solve the above-mentioned problems, and its purpose is to provide a thin film that can be easily produced, has high solvent selectivity, can control the varnish from a high viscosity to a low viscosity range, and has good coating properties regardless of the coating method. Anchor liquid crystal alignment agents, and provide weakly anchored liquid crystal alignment films and liquid crystal display elements that can simultaneously achieve no pretilt angle, low voltage driving and high-speed response when the voltage is OFF. [Means to solve the problem]

The inventors of the present invention conducted intensive studies to solve the above-mentioned problems, and as a result found that the above-mentioned problems can be solved, and completed the present invention having the following gist. That is, the present invention includes the following.

[1] A weakly anchored liquid crystal alignment agent used in the formation of the aforementioned liquid crystal alignment film in a liquid crystal cell (liquid crystal cell) having a liquid crystal and a liquid crystal alignment film, containing a polymerization of structural units represented by the following formula (1) Objects and components that exhibit weak anchoring. [Chemical 1] In formula (1), R ₁ and R ₂ each independently represent a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 3 carbon atoms, and X represents -OR _a , -N(R _a )(R _b ), or - SR _a , where R _a represents a hydrogen atom or a monovalent organic group, and R _b represents a monovalent group. [2] The weakly anchored liquid crystal alignment agent as described in [1], wherein X in the aforementioned formula (1) is a group selected from the following structures. [Chemicalization 2] In the formula, Y represents an oxygen atom or a sulfur atom, R ₁ represents a hydrogen atom or an alkyl group with 1 to 13 carbon atoms that may also contain a branched or cyclic structure, and R ₂ represents a linear or branched chain with 1 to 5 carbon atoms. Alkyl group, R ₃ represents a single bond or an alkylene group having 1 to 13 carbon atoms which may contain a branched structure or a cyclic structure, R ₄ represents an alkyl group having 1 to 13 carbon atoms which may contain a branched structure or a cyclic structure. , m represents an integer from 0 to 5, and n represents an integer from 1 to 5. When there are multiple R ₁ , R ₂ , R ₄ or Y, they may be the same or different. *Indicates the bonding part. [3] The weakly anchored liquid crystal alignment agent as described in [1] or [2], wherein the component exhibiting weak anchorage contains a group selected from the following polymer A, polymer B, and polymer C. At least 1 of them. Polymer A: a copolymer having a block segment (A) that is compatible with the liquid crystal and a block segment (B) that is incompatible with the liquid crystal or insoluble in the liquid crystal by calcination. Polymer B: a graft copolymer having a dry polymer and a branch polymer bonded to the aforementioned dry polymer as a side chain of the aforementioned dry polymer, and the aforementioned branch polymer is compatible with the aforementioned liquid crystal and the aforementioned stem polymer The polymer is incompatible with the aforementioned liquid crystal or is a graft copolymer incompatible with the aforementioned liquid crystal by calcination. Polymer C: a polymer having polymer units compatible with the liquid crystal and reacting with the polymer having the structural unit represented by formula (1) by heating. [4] The weakly anchored liquid crystal alignment agent according to [3], wherein the block segment (A) in the polymer A contains a compound selected from the group represented by the following formula (2), the following formula (3) The block segment (B) in the polymer A contains at least one of the group consisting of the compound represented by the following formula (4) and the compound represented by the following formula (5) as a constituent component. The compound represented by the following formula (6) serves as a constituent component. [Chemical 3] In formula (2), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, X represents a single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, or thioether bond, and R ₁ represents an alkyl group having 1 to 20 carbon atoms that may be inserted into a bonding group, and n is an integer of 1 to 2. When n is 2, the two X and R ₁ may be the same or different. [Chemical 4] In formula (3), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, S represents a single bond or a saturated hydrocarbon group having 1 to 6 carbon atoms that may be inserted into a bonding group, and T represents the following formula (3-T) To represent an organic radical, n is an integer from 1 to 2. When n is 2, the two T's can be the same or different. However, when n is 2, S represents a saturated hydrocarbon group with 1 to 6 carbon atoms that can be inserted into a bonding group. [Chemistry 5] In formula (3-T), * represents a bonding site. X is selected from the group consisting of single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, thioether bond, -Si(R ₁ )(R ₂ )-, -Si(R ₃ )(R ₄ ) -O-, and -N(R ₅ )- bonding groups, and R ₁ and R ₂ each independently represent an alkyl group bonded to Si, and R ₃ and R ₄ each independently represent an alkyl group bonded to Si is an alkyl group, and R ₅ represents a hydrogen atom or an alkyl group bonded to N, and Cy represents a non-aromatic cyclic group with 6 to 20 members. [Chemical 6] In formula (4), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, R ₁ represents a linear or branched aliphatic hydrocarbon group having 1 to 10 carbon atoms, and the three Xs each independently represent a hydrogen atom or The following formula (4-X). However, at least one of the three X's expresses (4-X). [Chemical 7] In formula (4-X), Y represents a single bond, -O-, -S- or -N(R)-, and R represents a hydrogen atom bonded to N or an alkyl group with 1 to 4 carbon atoms, and * represents Keying part. R ₂ , R ₃ , and R ₄ each independently represent an alkyl group having 1 to 6 carbon atoms or an aromatic hydrocarbon group which may have a substituent. [Chemical 8] In the formula (5), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, R ₁ to R ₃ each independently represents a single bond or an alkylene group having 1 to 6 carbon atoms that may be inserted into a bonding group, Ar represents an aromatic hydrocarbon group that may have a substituent, X ₁ and X _{2 each} independently represents a hydrogen atom or an aromatic hydrocarbon group that may have a substituent, R ₁ X ₁ and R ₂ X ₂ are bonded to R ₁ And the carbon atoms of R ₂ X ₂ can also form a ring together. However, the total carbon number of R ₁ X ₁ , R ₂ X ₂ and R ₃ is 1 or more. [Chemical 9] In formula (6), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and n is an integer of 1 to 2. Z represents a base represented by the following formula (6-Z). When n is 2, the two Zs can be the same or different. [Chemical 10] In formula (6-Z), L represents a group selected from the group consisting of trialkoxysilyl group, isocyanate group, blocked isocyanate group, epoxy group, oxetanyl group, vinyl group, allyl group, and tetrazolinyl group. Amine group, protected amine group, aniline group, protected aniline group, hydroxyl group, protected hydroxyl group, phenol group, protected phenol group, thiol group, protected thiol group, thiophenol group, protected thiophenol group, aldehyde group, carboxyl group , maleimide group, N-hydroxysuccinimide ester group, aromatic hydrocarbon group with 5 to 18 carbon atoms in the bonding group can also be inserted, aromatic hydrocarbon group with 5 to 18 carbon atoms in the bonding group can also be inserted Heterocyclic group, cinnamic acid group, cinnamic acid aromatic ester group, cinnamic acid alkyl ester group, cinnamon group, phenyl benzoate group, azophenyl group, N-benzylidene anilinyl group, distyryl group, and A functional group in the group consisting of tolanyl. J represents a single bond or an aliphatic hydrocarbon group having 1 to 6 carbon atoms. When K is bonded to an aromatic hydrocarbon group, it represents a linking group selected from a single bond, ether bond, ester bond, amide bond, urea bond, urethane bond, and thioether bond. Otherwise, it represents a single bond. key. *Indicates the bonding part. m represents an integer from 1 to 3. When m is 2 or 3, multiple K's and L's may be the same or different. However, when J is a single bond, m is 1. [5] The weakly anchored liquid crystal alignment agent according to [3], wherein the branch polymer in the polymer B is derived from a polymer monomer represented by the following formula (7). [Chemical 11] In the formula (7), P represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and Q represents a monomer obtained by polymerizing at least one or more monomers among the compounds represented by the following formulas (2) to (5). In the obtained structure, n is an integer from 1 to 2. When n is 2, the two Qs can be the same or different. [Chemical 12] In formula (2), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, X represents a single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, or thioether bond, and R ₁ represents an alkyl group having 1 to 20 carbon atoms that may be inserted into a bonding group, and n is an integer of 1 to 2. When n is 2, the two X and R ₁ may be the same or different. [Chemical 13] In formula (3), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, S represents a single bond or a saturated hydrocarbon group having 1 to 6 carbon atoms that may be inserted into a bonding group, and T represents the following formula (3-T) To represent an organic radical, n is an integer from 1 to 2. When n is 2, the two T's can be the same or different. However, when n is 2, S represents a saturated hydrocarbon group with 1 to 6 carbon atoms that can be inserted into a bonding group. [Chemical 14] In formula (3-T), * represents a bonding site. X is selected from the group consisting of single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, thioether bond, -Si(R ₁ )(R ₂ )-, -Si(R ₃ )(R ₄ ) -O-, and -N(R ₅ )- bonding groups, and R ₁ and R ₂ each independently represent an alkyl group bonded to Si, and R ₃ and R ₄ each independently represent an alkyl group bonded to Si is an alkyl group, and R ₅ represents a hydrogen atom or an alkyl group bonded to N, and Cy represents a non-aromatic cyclic group with 6 to 20 members. [Chemical 15] In formula (4), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, R ₁ represents a linear or branched aliphatic hydrocarbon group having 1 to 10 carbon atoms, and the three Xs each independently represent a hydrogen atom or The following formula (4-X). However, at least one of the three X's expresses (4-X). [Chemical 16] In formula (4-X), Y represents a single bond, -O-, -S- or -N(R)-, and R represents a hydrogen atom bonded to N or an alkyl group with 1 to 4 carbon atoms, and * represents Keying part. R ₂ , R ₃ , and R ₄ each independently represent an alkyl group having 1 to 6 carbon atoms or an aromatic hydrocarbon group which may have a substituent. [Chemical 17] In formula (5), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, R ₁ to R ₃ each independently represents a single bond or an alkylene group having 1 to 6 carbon atoms that may be inserted into a bonding group, Ar represents an aromatic hydrocarbon group that may have a substituent, X ₁ and X _{2 each} independently represents a hydrogen atom or an aromatic hydrocarbon group that may have a substituent, R ₁ X ₁ and R ₂ X ₂ are bonded to R ₁ And the carbon atoms of R ₂ X ₂ can also form a ring together. However, the total carbon number of R ₁ X ₁ , R ₂ X ₂ and R ₃ is 1 or more. [6] The weakly anchored liquid crystal alignment agent according to [3] or [5], wherein the dry polymer in the polymer B contains a compound represented by the following formula (6) as a constituent component. [Chemical 18] In formula (6), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and n is an integer of 1 to 2. Z represents a base represented by the following formula (6-Z). When n is 2, the two Zs can be the same or different. [Chemical 19] In formula (6-Z), L represents a group selected from the group consisting of trialkoxysilyl group, isocyanate group, blocked isocyanate group, epoxy group, oxetanyl group, vinyl group, allyl group, and tetrazolinyl group. Amine group, protected amine group, aniline group, protected aniline group, hydroxyl group, protected hydroxyl group, phenol group, protected phenol group, thiol group, protected thiol group, thiophenol group, protected thiophenol group, aldehyde group, carboxyl group , maleimide group, N-hydroxysuccinimide ester group, aromatic hydrocarbon group with 5 to 18 carbon atoms in the bonding group can also be inserted, aromatic hydrocarbon group with 5 to 18 carbon atoms in the bonding group can also be inserted Heterocyclic group, cinnamic acid group, cinnamic acid aromatic ester group, cinnamic acid alkyl ester group, cinnamon group, phenyl benzoate group, azophenyl group, N-benzylidene anilinyl group, distyryl group, and A functional group in the group consisting of diphenylethynyl groups. J represents a single bond or an aliphatic hydrocarbon group having 1 to 6 carbon atoms. When K is bonded to an aromatic hydrocarbon group, it represents a linking group selected from a single bond, ether bond, ester bond, amide bond, urea bond, urethane bond, and thioether bond. Otherwise, it represents a single bond. key. *Indicates the bonding part. m represents an integer from 1 to 3. When m is 2 or 3, multiple K's and L's may be the same or different. However, when J is a single bond, m is 1. [7] The weakly anchored liquid crystal alignment agent according to [3], wherein the polymer C is a polymer represented by the following formula (8). [Chemistry 20] In formula (8), A represents a polymer selected from the following formulas (8-A-1) to (8-A-16) that reacts with the aforementioned polymer having a structural unit represented by formula (1) by heating. An n-valent organic radical with a molecular weight of less than 300. Q is a divalent polymer unit compatible with the liquid crystal containing at least one selected from the group consisting of compounds represented by the following formulas (2) to (5) as a constituent component. R is 1 selected from the following formulas (8-R-1) to (8-R-11) with a molecular weight of 500 or less that does not react with the polymer having the structural unit represented by formula (1) by heating. Valence organic base. n is an integer between 1 and 2. When n is 2, the two Q and R can be the same or different respectively. [Chemistry 21] In formulas (8-A-1) to (8-A-16), R ₁ and R ₂ each independently represent a hydrogen atom or a linear or branched alkyl group with 1 to 12 carbon atoms, and R ₃ and R ₄ each independently represent G represents a single bond or a linear or branched alkylene group having 1 to 12 carbon atoms, and X represents an oxygen atom or a sulfur atom. *Indicates the bonding part. [Chemistry 22] In formulas (8-R-1) to (8-R-11), R ₁ and R ₂ each independently represent a hydrogen atom or a linear or branched alkyl group with 1 to 12 carbon atoms, and R ₃ and R ₄ each independently represent represents a single bond or a linear or branched alkylene group having 1 to 12 carbon atoms. *Indicates the bonding part. [Chemistry 23] In formula (2), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, X represents a single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, or thioether bond, and R ₁ represents an alkyl group having 1 to 20 carbon atoms that may be inserted into a bonding group, and n is an integer of 1 to 2. When n is 2, the two X and R ₁ may be the same or different. [Chemistry 24] In formula (3), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, S represents a single bond or a saturated hydrocarbon group having 1 to 6 carbon atoms that may be inserted into a bonding group, and T represents the following formula (3-T) To represent an organic radical, n is an integer from 1 to 2. When n is 2, the two T's can be the same or different. However, when n is 2, S represents a saturated hydrocarbon group with 1 to 6 carbon atoms that can be inserted into a bonding group. [Chemical 25] In formula (3-T), * represents a bonding site. X is selected from the group consisting of single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, thioether bond, -Si(R ₁ )(R ₂ )-, -Si(R ₃ )(R ₄ ) -O-, and -N(R ₅ )- bonding groups, and R ₁ and R ₂ each independently represent an alkyl group bonded to Si, and R ₃ and R ₄ each independently represent an alkyl group bonded to Si is an alkyl group, and R ₅ represents a hydrogen atom or an alkyl group bonded to N, and Cy represents a non-aromatic cyclic group with 6 to 20 members. [Chemical 26] In formula (4), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, R ₁ represents a linear or branched aliphatic hydrocarbon group having 1 to 10 carbon atoms, and the three Xs each independently represent a hydrogen atom or The following formula (4-X). However, at least one of the three X's expresses (4-X). [Chemical 27] In formula (4-X), Y represents a single bond, -O-, -S- or -N(R)-, and R represents a hydrogen atom bonded to N or an alkyl group with 1 to 4 carbon atoms, and * represents Keying part. R ₂ , R ₃ , and R ₄ each independently represent an alkyl group having 1 to 6 carbon atoms or an aromatic hydrocarbon group which may have a substituent. [Chemical 28] In the formula (5), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, R ₁ to R ₃ each independently represents a single bond or an alkylene group having 1 to 6 carbon atoms that may be inserted into a bonding group, Ar represents an aromatic hydrocarbon group that may have a substituent, X ₁ and X _{2 each} independently represents a hydrogen atom or an aromatic hydrocarbon group that may have a substituent, R ₁ X ₁ and R ₂ X ₂ are bonded to R ₁ And the carbon atoms of R ₂ X ₂ can also form a ring together. However, the total carbon number of R ₁ X ₁ , R ₂ X ₂ and R ₃ is 1 or more. [8] The weakly anchored liquid crystal alignment agent as described in any one of [4], [5], and [7], wherein M in the aforementioned formula (2) is any structure represented by the following, the aforementioned M in the formula (3) is any structure represented by the following, M in the aforementioned formula (4) is any structure represented by the following, M in the aforementioned formula (5) is any structure represented by the following. [Chemical 29] In the formula, R ₁ and R ₂ each independently represent a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms, and X, Y and Z each independently represent an oxygen atom or a sulfur atom. *, * ¹ and * ² represent a bonding site, and either * ¹ or * ² may be substituted by a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms. n represents an integer from 1 to 5. [9] The weakly anchored liquid crystal alignment agent as described in any one of [1] to [8], wherein the aforementioned polymer having a structural unit represented by formula (1) further has a structure represented by the following formula (9) unit. [Chemical 30] In formula (9), R ₃ , R ₄ , R ₅ , and R ₆ each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, -OC(=O)-R, -C(=O)- OR, -OR, or phenyl, and R represents an alkyl group having 1 to 6 carbon atoms. [10] A liquid crystal display element obtained by using the weakly anchored liquid crystal alignment agent described in any one of [1] to [9]. [11] The liquid crystal display element according to [10], which is a transverse electric field liquid crystal display element. [Effects of the invention]

According to the present invention, a stable liquid crystal alignment film can be produced by a much simpler method than the conventional technology. The coating property is good regardless of the coating method, and the solvent selectivity is wide. Solvents that have been conventionally used for production can be used. Therefore, it is possible to Reducing the step load imposed on the manufacturing of weakly anchored transverse electric field liquid crystal display devices in actual industrialization may improve the yield. In addition, by using the materials and methods of the present invention, it is possible to achieve high-speed response when the voltage is OFF, reduction of burn-in, high backlight transmittance in a low-temperature environment, and low-voltage driving compared to conventional technologies, thereby providing a stable Materials and transverse electric field liquid crystal display elements exhibiting excellent characteristics.

(Weak anchoring) "Weak anchoring" in the present invention refers to the force that controls the alignment of liquid crystal molecules to the substrate in the azimuthal or polar direction, but has no anchoring strength at all (that is, maintaining the position of the liquid crystal molecules, or Even if the alignment of the liquid crystal molecules changes, it means that the interface elastic energy will return to the original state), or even if there is, it is weaker than the intermolecular force of the liquid crystals. It refers to the weak anchoring of the present invention, azimuthal anchoring The intensity (A ₂ ) is smaller than 10 ^-5 [J/m ² ]. As described in Patent Document 3, it is known that by arranging a polymer that can form a completely wetted state with liquid crystal at the substrate interface and bringing it into contact with the liquid crystal, a polymer-liquid crystal mixed layer is formed and exhibits a weak anchoring state.

(Weakly anchored liquid crystal alignment film) In the present invention, "weakly anchored liquid crystal alignment film" refers to a film that forms a weakly anchored state by contact with liquid crystal. It is not limited to a solid film and also includes a liquid film covering a solid surface.

(Strong Anchor, Strong Anchor Liquid Crystal Alignment Film) In the present invention, "strong anchor" refers to the ability to control the alignment of liquid crystal molecules along a uniaxial alignment, and to maintain the alignment of the liquid crystal even if energy is applied from the outside, or even if the liquid crystal The anchoring strength that can return to its original position despite a change in the orientation of the molecules refers to the case where the azimuthal anchoring strength (A ₂ ) is greater than 10 ^-4 [J/m ² ] in the strong anchoring of the present invention. . In addition, "strongly anchored liquid crystal alignment film" means a film that forms a strong anchoring state by contact with liquid crystal, and is not limited to a solid film but also includes a liquid film covering a solid surface.

(Weakly anchored liquid crystal display element) A weakly anchored liquid crystal display element can be produced by coating the weakly anchored liquid crystal alignment film and the strongly anchored liquid crystal alignment film defined above on a substrate provided with electrodes, and laminating them in pairs. Weakly anchored liquid crystal display elements have an infinitely small azimuthal anchoring strength of one of the liquid crystal alignment films, so they can induce alignment changes in the liquid crystal with weak electric fields and external field energy, and can also align liquid crystal molecules in normally immobile areas. changes, so especially in display elements that use comb electrodes such as IPS and FFS, the liquid crystal molecules on the electrodes with weak electric field strength can also be driven. Therefore, compared with paired alignment films, both are strongly anchored. Liquid crystal display elements composed of liquid crystal alignment films can achieve high transmittance and low driving voltage.

The azimuthal anchoring strength is an index indicating the strength of the interface elastic energy between the liquid crystal molecules and the liquid crystal alignment film relative to the azimuthal direction. Methods for calculating the azimuth anchoring strength can use the torque balance method, strong electric field method, geometry method (external field application method), Frederik’s transition method, etc.

(PolymerRSM) By adding a small amount of "polymer RSM", the viscosity of coating varnish (such as liquid crystal alignment agent) can be easily increased. Therefore, by adjusting the amount of polymer RSM added, the viscosity of the varnish can be controlled. In addition, the polymer RSM has good solvent selectivity, and by containing the polymer RSM, it will give the coating varnish good coating properties, so it can be mixed with materials with poor coating properties to improve the overall coating properties of the material. improve.

Polymer RSM is a polymer having a structural unit represented by the following formula (1) (hereinafter, it may also be referred to as "polymer (RSM)").

[Chemical 31] In formula (1), R ₁ and R ₂ each independently represent a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 3 carbon atoms, and X represents -OR _a , -N(R _a )(R _b ), or - SR _a , where R _a represents a hydrogen atom or a monovalent organic group, and R _b represents a monovalent group.

X in the aforementioned formula (1) is preferably a group selected from the following structures.

[Chemical 32] In the formula, Y represents an oxygen atom or a sulfur atom, R ₁ represents a hydrogen atom or an alkyl group with 1 to 13 carbon atoms that may also contain a branched or cyclic structure, and R ₂ represents a linear or branched chain with 1 to 5 carbon atoms. Alkyl group, R ₃ represents a single bond or an alkylene group having 1 to 13 carbon atoms which may contain a branched structure or a cyclic structure, R ₄ represents an alkyl group having 1 to 13 carbon atoms which may contain a branched structure or a cyclic structure. , m represents an integer from 0 to 5, and n represents an integer from 1 to 5. When there are multiple R ₁ , R ₂ , R ₄ or Y, they may be the same or different. *Indicates the bonding part.

The polymer (RSM) can be obtained, for example, by reacting a polymer having a structural unit containing a maleic anhydride skeleton (maleic anhydride-based polymer) and one or more nucleophilic agents. In this reaction, the nucleophile will be added to the carbonyl group of the maleic anhydride skeleton, and the structural unit represented by the aforementioned formula (1) will be obtained by performing a ring-opening reaction.

The aforementioned polymer having a structural unit containing a maleic anhydride skeleton is preferably a maleic anhydride polymer (homopolymer or copolymer) containing a structural unit represented by the following formula (1') (hereinafter also referred to as structural unit (1')). ), more preferably a maleic anhydride copolymer (hereinafter also referred to as copolymer (mRSM)) containing a structural unit (1') and a structural unit represented by the following formula (9) (hereinafter also referred to as structural unit (9)).

[Chemical 33] In formula (1'), R ₁ and R ₂ each independently represent a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 3 carbon atoms. In formula (9), R ₃ , R ₄ , R ₅ , and R ₆ each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, -OC(=O)-R, -C(=O)- OR, -OR, or phenyl, and R represents an alkyl group having 1 to 6 carbon atoms.

That is, the polymer (RSM) preferably has the structural unit represented by formula (1) and the structural unit represented by formula (9).

The aforementioned structural unit (9) is, for example, derived from ethylene, propylene, n-butylene, isobutylene, n-pentene, n-hexene, alkyl acrylates and alkyl methacrylates having an alkyl carbon number of 1 to 4, and vinyl acetate. It is a structural unit of a monomer of an ester, a methyl vinyl ether, and a styrenic compound represented by the following formula (10).

[Chemical 34] In formula (10), R is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and the benzene ring may be optionally substituted with an alkyl group having 1 to 4 carbon atoms or a hydroxyl group.

Preferable examples of the alkyl acrylates having 1 to 4 carbon atoms in the alkyl group include methyl acrylate, ethyl acrylate, isopropyl acrylate, n-propyl acrylate, n-butyl acrylate, and mixtures thereof. Ideal examples of alkyl methacrylates having 1 to 4 carbon atoms in the alkyl group include: methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-propyl methacrylate, n-propyl methacrylate Butyl esters, and their mixtures. A mixture of alkyl methacrylates having 1 to 4 carbon atoms in the alkyl group and alkyl acrylates having 1 to 4 carbon atoms in the alkyl group can also be used. Ideal examples of the styrenic compound include styrene, α-methylstyrene, p-methylstyrene, tertiary butylstyrene, and mixtures thereof. It is also possible to use a mixture of a styrenic compound, an alkyl acrylate ester having an alkyl group having 1 to 4 carbon atoms, and/or an alkyl methacrylate ester. Among them, isobutylene is particularly suitable, or isobutylene and a mixture of 1-butene and 2-butene are preferably used.

The aforementioned structural unit (1') is preferably 10 to 50 mol%, particularly preferably 30 to 50 mol%, of all the structural units constituting the copolymer (mRSM).

Regarding the molecular weight of the copolymer (mRSM), the weight average molecular weight is preferably 10,000 to 1,000,000, more preferably 50,000 to 500,000.

Commercially available products can be used as the copolymer (mRSM), and examples thereof include ISOBAM-06, ISOBAM-10, and ISOBAM-18 (all manufactured by Kuraray Co., Ltd.).

Examples of the nucleophile include the following compounds.

[Chemical 35] In the formula, Y represents an oxygen atom or a sulfur atom, R ₁ represents a hydrogen atom or an alkyl group with 1 to 13 carbon atoms that may also contain a branched or cyclic structure, and R ₂ represents a linear or branched chain with 1 to 5 carbon atoms. Alkyl group, R ₃ represents a single bond or an alkylene group having 1 to 13 carbon atoms which may contain a branched structure or a cyclic structure, R ₄ represents an alkyl group having 1 to 13 carbon atoms which may contain a branched structure or a cyclic structure. , m represents an integer from 0 to 5, and n represents an integer from 1 to 5. When there are multiple R ₁ , R ₂ , R ₄ or Y, they may be the same or different. *Indicates the bonding part.

The reaction between the polymer having a structural unit containing a maleic anhydride skeleton and the nucleophile is preferably carried out in an organic solvent. Examples of organic solvents used include alcohols, ethers, ketones, amides, esters, and hydrocarbon compounds. In the above reaction, the reaction temperature is preferably 20°C to 200°C, more preferably 40°C to 150°C. In addition, the reaction time is preferably 1 to 168 hours, more preferably 8 to 72 hours. The reaction solution in which the polymer is dissolved can be used directly, or the precipitate obtained by pouring the reaction solution into a large amount of poor solvent can be dried under reduced pressure, and the reaction solution can be distilled off under reduced pressure in an evaporator. Known separation methods such as the method are used to prepare the polymer composition (for example, a liquid crystal alignment agent) after separating the polymer contained in the reaction solution.

The reaction amount of the nucleophile is preferably 0.5 to 10 equivalents, more preferably 1 to 5 equivalents, relative to the acid anhydride group having the structural unit (1').

When performing a ring-opening reaction on a cyclic acid anhydride group, it is advisable to use a small amount of catalyst to promote the reaction. Examples of the catalyst include: triethylamine, N,N,N',N'-tetramethylethylenediamine, pyridine, 4-dimethylaminopyridine, imidazole, 2-methylimidazole, 1,8-bis Azabicyclo[5.4.0]-7-undecene, 1,5-diazabicyclo[4.3.0]-5-nonene, 1,4-diazabicyclo[2.2.2]octane, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, 1,8-bis(dimethylamino)naphthalene, the catalyst used is 1 mole part based on the cyclic acid anhydride group, Usually it is 0.000001~0.1 molar part, preferably 0.00001~0.01 molar part.

The polymer (RSM) of the present invention may further have structural units other than the structural units represented by the aforementioned formula (1) and formula (9). Examples of structural units other than the structural units represented by formula (1) and formula (9) include acrylic acid, methacrylic acid, α-ethyl acrylic acid, 2-hydroxyethyl (meth)acrylic acid, 4-vinyl benzoic acid, Maleic acid and other carboxyl-containing compounds; 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, N-hydroxymethyl Compounds containing hydroxyl groups such as (meth)acrylamide; compounds containing long-chain alkyl groups such as isooctyl acrylate, isodecyl acrylate, lauryl acrylate, decyl methacrylate, stearyl acrylate, etc.; (methyl) Compounds containing alicyclic groups such as cyclohexyl acrylate; compounds containing benzene rings such as 2-phenoxyethyl acrylate and ethoxylated nonylphenyl acrylate; glycidyl (meth)acrylate, ( Methylglycidyl methacrylate, 4-(glycidoxy)butyl (meth)acrylate and other epoxyethyl-containing compounds; 2-methacryloyloxyethyl isocyanate [KARENZMOIR Compounds with isocyanate groups or protected isocyanate groups such as 2-[(3,5-dimethylpyrazolyl)carbonylamino]ethyl methacrylate (KARENZMOI-BP, manufactured by Showa Denko Corporation) ; Structural unit of compounds with tetrahydropyranyl group such as tetrahydrofurfuryl methacrylate.

The polymer (RSM) may contain one type of structural unit represented by formula (9) alone, or may contain two or more types. The content of the structural unit represented by formula (9) is preferably 50 to 90 mol%, and more preferably 30 to 70 mol% relative to the total structural units of the polymer (RSM).

The content of the polymer (RSM) used in the present invention is preferably 1 to 99 mass %, more preferably 5 to 70 mass %, and 10 to 50 mass % relative to the total polymer components contained in the weakly anchored liquid crystal alignment agent. Quality % couldn't be better. The polymer (RSM) can be used individually by 1 type or in combination of 2 or more types.

(polymer alloy) One embodiment of the "polymer alloy" in the present invention is a polymer alloy composed of the aforementioned polymer (RSM) having the structural unit represented by formula (1) and a component exhibiting weak anchoring properties. Weakly anchored liquid crystal alignment agents are used to form films that align liquid crystals used in liquid crystal display elements, that is, to form liquid crystal alignment films.

The polymer alloy of the present invention is characterized in that it is obtained by mixing the aforementioned polymer (RSM) having the structural unit represented by formula (1) and a component exhibiting weak anchoring properties. The component exhibiting weak anchoring properties is preferably polymer A, polymer B, or polymer C described below.

In the pamphlet of International Publication No. 2019/004433, it has been proposed to apply a weakly anchored liquid crystal display element using a high-density graft copolymer (so-called polymer brush) that is a living polymerization branch polymer. The polymer brush is synthesized using the grafting from method, and must be synthesized using living polymerization. In addition, some people have tried to improve the adhesion between the substrate and the polymer by introducing into the branch polymer a group that contributes to improving the adhesion with the substrate. However, if a large amount is introduced, the weak anchorage may be damaged, and according to reports The density of branched polymers is considered to be very high, so it is difficult to cause solvation with solvents, and it is thought that the affinity for solvents with high boiling points and high polarity, such as NMP and γ-butyrolactone, is particularly impaired.

During the applicant's verification, research was also carried out on weakly anchored liquid crystal alignment agents using block copolymers made from living polymerization using non-polymer brushes, but all failed to achieve the solvent selectivity and adhesion strength of the polymer. The result of the decrease is considered to be a problem common to polymers that are precisely synthesized, just like polymer brushes. The results are described in the Examples.

The characteristics of the polymer alloy of the present invention are that it is obtained by mixing a polymer that does not exhibit weak anchoring (RSM) and a polymer that exhibits a weak anchoring component (also called a "weak anchoring component"). As specific examples in the following examples, the polymer (RSM) can control the viscosity of the varnish depending on the mixing ratio. Therefore, it can be used from inkjet coating that requires lower viscosity to printing coating that requires higher viscosity. Good coating properties depend on the coating method. In addition, the polymer RSM has good solvent selectivity and provides good coating properties to the coating varnish by containing this polymer. Therefore, by mixing it with a material with poor coating properties, the coating properties of the entire material can be improved. . It is presumed that this is due to the effect of hydrogen bonding from the carboxylic acid contained in the polymer RSM. On the other hand, the weak anchoring component contributes to the formation of the weak anchoring state, and the use of the weak anchoring component can achieve low driving voltage and high transmittance. In addition, the weak anchoring component will phase separate during the coating and calcining steps due to the difference in polarity and thermal expansion rate with the polymer (RSM), and will selectively segregate on the outermost surface of the alignment film, thereby maintaining good weak anchorage.

(Polymer A) One embodiment of the polymer A is a copolymer having a block segment (A) that is compatible with liquid crystal and a block segment (B) that is incompatible with liquid crystal or insoluble in the liquid crystal by calcination. Polymer A is, for example, a linear copolymer composed of two or more types of block segments obtained by living polymerization, and at least one block segment is composed of a block segment (A) that dissolves in liquid crystals. , a polymer in which at least one block segment is composed of a block segment (B) that does not dissolve in liquid crystal or is insoluble in liquid crystal due to cross-linking or the like.

The block segment (A) in polymer A preferably contains a compound selected from the group consisting of a compound represented by the following formula (2), a compound represented by the following formula (3), a compound represented by the following formula (4), and a compound represented by the following formula (5) At least one of the group of compounds serves as a constituent component. The block segment (B) in the polymer A preferably contains a compound represented by the following formula (6) as a constituent component. Polymer A is preferably a polymer in which the block segment (A) in polymer A is synthesized from at least one selected from the group consisting of compounds represented by the following formulas (2) to (5), and embedded Segment Segment (B) is a polymer synthesized from a compound represented by the following formula (6).

One embodiment of polymer A is a copolymer having block segments (A') and block segments (B'). The block segment (A') preferably contains a compound selected from the compound represented by the following formula (2), the compound represented by the following formula (3), the compound represented by the following formula (4), and the compound represented by the following formula (5) At least one member of the group serves as a component. The block segment (B') in the polymer A preferably contains a compound represented by the following formula (6) as a constituent component.

The applicant of this case discovered a radical polymerizable compound contained in a liquid crystal composition that can stably produce a weakly anchored transverse electric field liquid crystal display element without generating a pretilt angle, and is represented by the following formula (2) Compounds, compounds represented by formula (3), compounds represented by formula (4), and compounds represented by formula (5) contribute to the generation of weak anchors, and applications have been filed (Japanese Patent Application No. 2020-134149, Japanese Patent Application No. 2020-163212, Japanese Special Application No. 2021-041196, WO2022/030602, WO/2022/071286, WO/2022/196565, WO2019/004433, these applications and disclosures are incorporated by reference to the same extent as if fully expressly stated. The contents of the gazette are incorporated into this manual).

In addition, the applicant of this case found that the weakly anchored liquid crystal alignment agent containing polymer A can produce a weakly anchored film more easily and stably than the conventional method, and can provide a stable structure without generating a pretilt angle even in narrow unit cell gaps. At the same time, low-voltage driving and high-speed response when the voltage is turned off can be achieved. In addition, burn-in can be reduced, and a transverse electric field liquid crystal display element with high backlight transmittance and low-voltage driving can be realized in a low-temperature environment. An application has been filed (Japanese Patent Application). No. 2021-96448, WO2022/260048. By citing this, the contents of these applications and publications are incorporated into this specification to the same extent as fully expressly stated).

The copolymer may have three or more types of block segments. The copolymer is preferably a copolymer whose main chain is unbranched and extends linearly.

[Chemical 36] In formula (2), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, X represents a single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, or thioether bond, and R ₁ represents an alkyl group having 1 to 20 carbon atoms that may be inserted into a bonding group, and n is an integer of 1 to 2. When n is 2, the two X and R ₁ may be the same or different. Examples of the bonding group that may be inserted into the alkyl group having 1 to 20 carbon atoms in the bonding group include: ether bond, ester bond, amide bond, urethane bond, urea bond, thioether bond, -Si( R ₁₁ )(R ₁₂ )-(R ₁₁ and R ₁₂ independently represent an alkyl group bonded to Si), -Si(R ₁₃ )(R ₁₄ )-O-(R ₁₃ and R ₁₄ independently represent Alkyl group bonded to Si), -N(R ₁₅ )-(R ₁₅ represents a hydrogen atom or alkyl group bonded to N). Examples of the alkyl group in R ₁₁ to R ₁₅ include alkyl groups having 1 to 6 carbon atoms.

[Chemical 37] In formula (3), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, S represents a single bond or a saturated hydrocarbon group having 1 to 6 carbon atoms that may be inserted into a bonding group, and T represents the following formula (3-T) To represent an organic radical, n is an integer from 1 to 2. When n is 2, the two T's can be the same or different. However, when n is 2, S represents a saturated hydrocarbon group with 1 to 6 carbon atoms that can be inserted into a bonding group.

[Chemical 38] In formula (3-T), * represents a bonding site. X is selected from the group consisting of single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, thioether bond, -Si(R ₁ )(R ₂ )-(R ₁ and R ₂ independently represents an alkyl group bonded to Si), -Si(R ₃ )(R ₄ )-O- (R ₃ and R ₄ each independently represent an alkyl group bonded to Si), and -N(R ₅ )- (R ₅ represents a hydrogen atom or alkyl group bonded to N), and Cy represents a non-aromatic cyclic group with 6 to 20 members.

The saturated hydrocarbon group in S in formula (3) refers to an n+1 valent group obtained by removing n+1 hydrogen atoms from a saturated hydrocarbon (n is the same integer as n in formula (3)). When n is 1, the saturated hydrocarbon group is an alkylene group. In S in formula (3), a saturated hydrocarbon group having 1 to 6 carbon atoms with a bonding group inserted therein means that n+1 of a bonding group has been inserted between the carbon-carbon spaces in the saturated hydrocarbon group with 2 to 6 carbon atoms. A valent group, or a divalent group in which a bonding group is inserted between a saturated hydrocarbon group having 1 to 6 carbon atoms and an atom (for example, a carbon atom) bonded thereto. Examples of the bonding group in S in formula (3) include: carbon-carbon unsaturated bond, ether bond (-O-), ester bond (-COO- or -OCO-), amide bond (-CONH- or -NHCO-) etc. Examples of carbon-carbon unsaturated bonds include: carbon-carbon double bonds, etc. However, a saturated hydrocarbon group with 1 to 6 carbon atoms in which a carbon-carbon double bond is inserted should have a carbon-carbon double bond within it rather than within it. end. When n is 1, an alkylene group having 1 to 6 carbon atoms that may be inserted into the bonding group includes, for example, an alkylene group having 1 to 6 carbon atoms, an oxyalkylene group having 1 to 6 carbon atoms, and the like. The alkylene group having 1 to 6 carbon atoms may be a linear alkylene group, a branched alkylene group, or a cyclic alkylene group.

R ₁ and R ₂ of -Si(R ₁ )(R ₂ )- in X of the formula (3-T) are each independently an alkyl group bonded to Si, for example, an alkyl group having 1 to 6 carbon atoms. R 3 _and R ₄ of -Si(R ₃ )(R ₄ )-O- in X of formula (3-T) are each independently an alkyl group bonded to Si, for example, an alkyl group having 1 to 6 carbon atoms. base. R ₅ in -N(R ₅ )- in X of formula (3-T) is a hydrogen atom or an alkyl group bonded to N. The alkyl group is, for example, an alkyl group having 1 to 6 carbon atoms.

In the formula (3-T), Cy is a non-aromatic cyclic group with 6 to 20 members, preferably a non-aromatic cyclic group with 8 to 18 members. In addition, Cy may be a non-aromatic cyclic group with 12 to 20 members. In formula (3-T), X is bonded to the atoms in Cy constituting the ring. Examples of the ring-constituting atoms in the non-aromatic cyclic group include carbon atoms, oxygen atoms, nitrogen atoms, silicon atoms, and the like. The bonds between the atoms constituting the ring can be single bonds, double bonds, or parabonds, preferably single bonds. Examples of the ring in the non-aromatic cyclic group include cyclic alkane, cyclic ether, cyclic siloxane, and the like. Examples of cyclic ethers include crown ethers. For example, in 12-crown-4 ether, the atoms constituting the ring are carbon atoms and oxygen atoms, and the number of members is 12. The ring can be a single ring or multiple rings. The number of rings in the polycyclic ring may be, for example, 2 to 4. The bonding modes between the rings in the polycyclic ring include, for example, the following three types. ･Share 1 atom: for example, spiro compounds ･Shared 2 atoms: When 2 rings share 2 atoms like decalin ･Bridged structure: treated as a case where two rings share more than three atoms, such as norbornane In addition, when it is a polycyclic ring, the number of ring members shall be the number of atoms constituting the ring. For example, norbornane has a 7-membered ring. On the atoms constituting the ring, a hydrogen atom may be replaced by a halogen atom, or an alkyl group having 1 to 6 carbon atoms may be bonded thereto. Examples of halogen atoms include fluorine atoms, chlorine atoms, and the like.

[Chemical 39] In formula (4), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, R ₁ represents a linear or branched aliphatic hydrocarbon group having 1 to 10 carbon atoms, and the three Xs each independently represent a hydrogen atom or The following formula (4-X). However, at least one of the three X's expresses (4-X).

[Chemical 40] In formula (4-X), Y represents a single bond, -O-, -S- or -N(R)-, and R represents a hydrogen atom bonded to N or an alkyl group with 1 to 4 carbon atoms, and * represents Keying part. R ₂ , R ₃ , and R ₄ each independently represent an alkyl group having 1 to 6 carbon atoms or an aromatic hydrocarbon group which may have a substituent.

The aliphatic hydrocarbon group in R ₁ in formula (4) has a carbon number of 1 to 10, or may have a carbon number of 1 to 8, a carbon number of 1 to 6, or a carbon number of 1 to 4.

The alkyl group having 1 to 6 carbon atoms in R ₂ , R ₃ , and R ₄ in the formula (4-X) may be, for example, an alkyl group having 1 to 5 carbon atoms, or may be an alkyl group having 1 to 4 carbon atoms. . These alkyl groups may have a straight chain structure or a branched structure.

The aromatic hydrocarbon groups in R ₂ , R ₃ , and R ₄ in formula (4-X) may be unsubstituted, or the hydrogen atom may be substituted by a substituent. Examples of substituents of the aromatic hydrocarbon group that may have a substituent include: halogen atom, alkyl group having 1 to 4 carbon atoms, alkoxy group having 1 to 4 carbon atoms, halogenated alkyl group having 1 to 4 carbon atoms, 1 to 4 halogenated alkoxy groups, etc. The halogenation in the halogenated alkyl group and the halogenated alkoxy group may be full halogenation or partial halogenation. Examples of halogen atoms include fluorine atoms, chlorine atoms, and the like. Examples of the aromatic hydrocarbon group that may have a substituent include phenyl and naphthyl. The number of substituents in the aromatic hydrocarbon group is not particularly limited.

In formula (4), the number of formula (4-X) is more than 1, may be 1, may be 2, may be 3. In formula (4), the three X systems are independent. Therefore, in formula (4), when there are two or more formulas (4-X), the two or more formulas (4-X) may have the same structure or different structures.

In formula (4-X), at least one of R ₂ , R ₃ , and R ₄ may be an aromatic hydrocarbon group that may have a substituent. Therefore, in formula (4-X), one of R ₂ , R ₃ , and R ₄ may be an aromatic hydrocarbon group that may have a substituent, or two of R ₂ , R ₃ , and R ₄ may be The group may be an aromatic hydrocarbon group which may have a substituent, or three of R ₂ , R ₃ and R ₄ may be an aromatic hydrocarbon group which may have a substituent.

[Chemical 41] In formula (5), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, R ₁ to R ₃ each independently represents a single bond or an alkylene group having 1 to 6 carbon atoms that may be inserted into a bonding group, Ar represents _an aromatic hydrocarbon group that may have a substituent, X1 _{and X2 each} independently represents a hydrogen atom or an aromatic hydrocarbon group that may have _a substituent, R _{1 2} X ₂ carbon atoms can also form a ring together. However, the total carbon number of R ₁ X ₁ , R ₂ X ₂ and R ₃ is 1 or more.

Among R ₁ to R ₃ in the formula (5), an alkylene group with 1 to 6 carbon atoms in which a bonding group is inserted means that a bond is inserted between carbon and carbon in the alkylene group with 1 to 6 carbon atoms. A divalent group of a group, or a divalent group in which a bonding group is inserted between an alkylene group having 1 to 6 carbon atoms and the carbon atom bonded thereto. Examples of the bonding group include: carbon-carbon unsaturated bond, ether bond (-O-), ester bond (-COO- or -OCO-), amide bond (-CONH- or -NHCO-), etc. Examples of the unsaturated bond include carbon-carbon double bonds. The alkylene group having 1 to 6 carbon atoms in which the bonding group is inserted preferably has a carbon-carbon double bond in its interior rather than at its terminal end. Examples of the alkylene group having 1 to 6 carbon atoms that may be inserted into the bonding group include an alkylene group having 1 to 6 carbon atoms, an oxyalkylene group having 1 to 6 carbon atoms, and the like. The oxygen atom in the oxyalkylene group having 1 to 6 carbon atoms is, for example, bonded to the carbon atom bonded to M, R ₁ , R ₂ and R ₃ in the formula (5). The alkylene group having 1 to 6 carbon atoms may be a linear alkylene group, a branched alkylene group, or a cyclic alkylene group.

Examples of the aromatic hydrocarbon group that may have a substituent in X ₁ and X ₂ of the formula (5) include phenyl group, naphthyl group, etc. that may have a substituent. Examples of the substituent include a halogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a halogenated alkyl group having 1 to 4 carbon atoms, and a halogenated alkoxy group having 1 to 4 carbon atoms. The halogenation in the halogenated alkyl group and the halogenated alkoxy group may be full halogenation or partial halogenation. Examples of halogen atoms include fluorine atoms, chlorine atoms, and the like.

Examples of R ₁ in formula (5) include a single bond, an alkylene group having 1 to 6 carbon atoms, and the like. More specific examples of the alkylene group having 1 to 6 carbon atoms include a linear alkylene group having 1 to 6 carbon atoms. Examples of R ₂ in formula (5) include a single bond, an alkylene group having 1 to 6 carbon atoms, and the like. More specific examples of the alkylene group having 1 to 6 carbon atoms include a linear alkylene group having 1 to 6 carbon atoms. Examples of R ₃ in formula (5) include a single bond, an alkylene group having 1 to 6 carbon atoms, and the like. More specific examples of the alkylene group having 1 to 6 carbon atoms include a linear alkylene group having 1 to 6 carbon atoms. Examples of X ₁ in the formula (5) include a hydrogen atom, a phenyl group, and the like. Examples of X ₂ in the formula (5) include a hydrogen atom, a phenyl group, and the like. Examples of Ar in formula (5) include phenyl and the like.

If _{the total} number _of carbon atoms _of R ₁ Moreover, the total number of carbon atoms of R ₁ , R ₂ and R ₃ in formula (5) may be, for example, 18 or less, 15 or less, or 10 or less. In addition, when X ₁ and X ₂ in formula (5) are hydrogen atoms, there is no particular limitation as long as the total carbon number of R ₁ , R ₂ and R ₃ is 1 or more, and may be 2 or more. In addition, when at least one of X ₁ and X ₂ in formula (5) is an aromatic hydrocarbon group which may have a substituent, the total carbon number of R ₁ , R ₂ and R ₃ may be 0.

In the formula (5), examples of the ring formed by R ₁ X ₁ and _{R 2 X 2} and the carbon atoms bonded to R ₁ X ₁ and R 2 ~13 hydrocarbon ring. The bonding group is as described above.

By using the structure of the above compound, it is easier to achieve high-speed response when the voltage is OFF, reduction of burn-in, high backlight transmittance in low-temperature environments, and low-voltage driving.

Block segment (A) and block segment (A’) are mainly responsible for swelling on the liquid crystal in a thin film state and forming a weak anchoring film. Depending on the molecular weight of the block segment (A) and the block segment (A’), the physical properties of the weakly anchored film will be significantly different, so optimization of the molecular weight is not important. From the viewpoint of forming a good weakly anchored film, the ideal molecular weight of the block segment (A) and the block segment (A’) is 1,000 to 100,000, and more preferably 3,000 to 50,000. In addition, the molecular weight is a number average molecular weight (Mn) in terms of polystyrene measured by gel permeation chromatography (GPC). In addition, the molecular weight distribution PDI (Mw/Mn) expressed by the ratio of the polystyrene-converted weight average molecular weight Mw and the number average molecular weight Mn measured by GPC is preferably 3.0 or less, more preferably 2.0 or less.

The block segment (A) and the block segment (A') may be a homopolymer of the above compounds, or a plurality of compounds may be used in combination. When combined, it can be random copolymerization or block copolymerization. When combined with compound species compatible with liquid crystals, the ratio is not particularly limited regardless of the combination method. When combined with the compound species insoluble in liquid crystal described below, from the viewpoint of maintaining properties, the ideal combination ratio of the compound species insoluble in liquid crystal is 30 mol% or less, more preferably 20 mol% or less, but is not limited thereto. These combination methods, combined compound species, and combination ratios should be used within the range in which the intended physical properties, display properties, electrical properties, etc. can be obtained.

The block segment (B) and the block segment (B') contribute to the stability of the film in the thin film state.

Block segment (B) and block segment (B') preferably have a compound selected from the group consisting of trialkoxysilyl group, isocyanate group, blocked isocyanate group, epoxy group, oxetanyl group, vinyl group, Allyl, tetrazoline, amine, protected amine, aniline, protected aniline, hydroxyl, protected hydroxyl, phenol, protected phenol, thiol, protected thiol, thiophenol, protected Thiophenyl group, aldehyde group, carboxyl group, maleimide group, N-hydroxysuccinimide ester group, aromatic hydrocarbon group with 5 to 18 carbon atoms in the bonding group can also be inserted into the bonding group. Aromatic heterocyclic group with 5 to 18 carbon atoms, cinnamic acid group, cinnamic acid aromatic ester group, cinnamic acid alkyl ester group, cinnamon group, benzoic acid phenyl ester group, azophenyl group, N-benzylidene group The side chain structure of at least one functional group in the group consisting of aniline group, distyryl group, and distylacetylene group. Specific examples of the bonding group include the specific examples of the bonding group listed in the description of formula (1). In this case, the block segment (B) and the block segment (B') contain, for example, a polymerizable compound having the above-mentioned functional group and a polymerizable group having a polymerizable unsaturated hydrocarbon group as a constituent component.

An example of the polymerizable compound used to form the block segment (B) and the block segment (B') is represented by the following formula (6).

[Chemical 42] In formula (6), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and n is an integer of 1 to 2. Z represents a base represented by the following formula (6-Z). When n is 2, the two Zs can be the same or different.

[Chemical 43] In formula (6-Z), L represents a group selected from the group consisting of trialkoxysilyl group, isocyanate group, blocked isocyanate group, epoxy group, oxetanyl group, vinyl group, allyl group, and tetrazolinyl group. Amine group, protected amine group, aniline group, protected aniline group, hydroxyl group, protected hydroxyl group, phenol group, protected phenol group, thiol group, protected thiol group, thiophenol group, protected thiophenol group, aldehyde group, carboxyl group , maleimide group, N-hydroxysuccinimide ester group, aromatic hydrocarbon group with 5 to 18 carbon atoms in the bonding group can also be inserted, aromatic hydrocarbon group with 5 to 18 carbon atoms in the bonding group can also be inserted Heterocyclic group, cinnamic acid group, cinnamic acid aromatic ester group, cinnamic acid alkyl ester group, cinnamon group, phenyl benzoate group, azophenyl group, N-benzylidene anilinyl group, distyryl group, and A functional group in the group consisting of diphenylethynyl groups. J represents a single bond or an aliphatic hydrocarbon group having 1 to 6 carbon atoms. When K is bonded to an aromatic hydrocarbon group, it represents a linking group selected from a single bond, an ether bond, an ester bond, an amide bond, a urea bond, a urethane bond, and a thioether bond. Otherwise, Represents a single key. *Indicates the bonding part. m represents an integer from 1 to 3. When m is 2 or 3, multiple K's and L's may be the same or different. However, when J is a single bond, m is 1.

Block segment (B) and block segment (B’) have side chain structures that are incompatible with liquid crystals or become incompatible with liquid crystals through calcination. Compound species that are incompatible with liquid crystals used in the formation of block segments (B) and block segments (B') include: highly polar compound species, or compound species with a rigid structure, block chain Examples of compound species that are used to form segment (B) and block segment (B′) and become incompatible with liquid crystals through calcination include thermosetting compound species.

An example of the polymerizable compound used to form the block segment (B) and the block segment (B') is a compound having a polymerizable group having a polymerizable unsaturated hydrocarbon group and a highly polar structure. The above-mentioned highly polar structure is preferably the following structure. However, it is not limited to this.

[Chemical 44] X and Y each independently represent an oxygen atom or a sulfur atom. R ₁ and R ₂ each independently represent a single bond or an alkylene group having 1 to 18 carbon atoms. R ₃ represents an alkyl group having 1 to 18 carbon atoms. One of A ₁ , A ₂ and A ₃ represents N, and the remaining two represent CH. One of _A4 and _A5 represents N, and the remaining one represents CH. * represents the bonding part, and n represents an integer from 0 to 4.

An example of the polymerizable compound used to form the block segment (B) and the block segment (B') is a compound having a polymerizable group having a polymerizable unsaturated hydrocarbon group and a rigid structure. The above-mentioned rigid structure is preferably as follows. However, it is not limited to this.

[Chemical 45] X, Y and Z each independently represent an oxygen atom or a sulfur atom. R ₁ and R ₂ each independently represent a single bond or an alkylene group having 1 to 18 carbon atoms. R ₃ represents an alkyl group having 1 to 18 carbon atoms. * represents the bonding part, n represents an integer from 1 to 5.

An example of the polymerizable compound used to form the block segment (B) and the block segment (B') is a compound having a polymerizable group having a polymerizable unsaturated hydrocarbon group and a thermosetting structure. The above-mentioned thermosetting structure is preferably as follows. However, it is not limited to this.

[Chemical 46] X, Y and Z each independently represent an oxygen atom or a sulfur atom. R ₁ , R ₂ and R ₃ each independently represent an alkyl group having 1 to 18 carbon atoms. R ₄ and R ₅ each independently represent a single bond or an alkylene group having 1 to 18 carbon atoms. * represents the bonding part, n represents an integer from 0 to 5.

In the present invention, the polymerizable group having a polymerizable unsaturated hydrocarbon group preferably has the following structure.

[Chemical 47] In the formula, R ₁ and R ₂ each independently represent a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms, and X, Y and Z each independently represent an oxygen atom or a sulfur atom. *, * ¹ and * ² represent a bonding site, and either * ¹ or * ² may be substituted by a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms. n represents an integer from 1 to 5.

The block segment (B) and the block segment (B’) are mainly responsible for stabilization in the film state and do not have a significant impact on the physical properties of the weakly anchored film. As long as the block segment (B) and the block segment (B') are used to supplement the stability of the membrane, the optimal molecular weight that can supplement the stability of the membrane depends on the species of the compound used, so there is no particular limit. In addition, depending on the compound species used, it is beneficial to solvent selectivity or coating properties, so it is appropriate to control the compound species constituting the block segment (B) and the block segment (B') in accordance with the use and purpose. and its molecular weight.

Regarding the block segment (B) and the block segment (B'), the above-mentioned polymerizable compound may be used alone or in combination of a plurality of compounds. As mentioned above, the block segment (B) and the block segment (B') are block segments that only contribute to the stability of the film at best, and do not have a significant impact on the weak anchoring properties. As long as they supplement the stability of the film For stabilization, there are no special restrictions on the compound species to be combined and the combination method.

One embodiment of polymer A is characterized by a copolymer having block segments (A) that are compatible with liquid crystals and insoluble in liquid crystals or block segments (B) that are insoluble in liquid crystals. The number of blocks is not limited, for example It may be a structure having multiple block segments like (A)-(B)-(A), and the number or combination of the block segments is not particularly limited. In addition, it is also possible to introduce a block segment that imparts electrical characteristics. On the other hand, from the viewpoint of ease of synthesis, etc., the number of block segments is preferably about 2 to 4, and from the viewpoint of film stability, the block segments at the polymer terminals are preferably block segments (B ).

As mentioned above, the block segment (A) that is compatible with liquid crystals is responsible for the weak anchoring properties, and the molecular weight of the block segment (A) has a significant impact on the properties. Therefore, the relationship between the block segment (A) and the block chain The molecular weight ratio of segment (B) is not limited.

The characteristic of one embodiment of polymer A is that it is a copolymer with block segments (A') and block segments (B'). The number of blocks is not limited. For example, it can be (A')- (B')-(A') generally has a structure of multiple block segments, and the number or combination of the block segments is not particularly limited. In addition, it is also possible to introduce a block segment that imparts electrical characteristics. On the other hand, from the viewpoint of ease of synthesis, etc., the number of block segments is preferably about 2 to 4, and from the viewpoint of film stability, the block segments at the polymer terminals are preferably block segments (B ').

As mentioned above, the block segment (A') is responsible for the weak anchoring properties, and the molecular weight of the block segment (A') greatly affects the properties, so the block segment (A') and the block segment ( The molecular weight ratio of B') is not limited.

Polymer A can be obtained, for example, by living polymerization. Living polymerization refers to a polymerization reaction that is not accompanied by side reactions such as chain transfer reaction and stop reaction. It can obtain a polymer with a narrow molecular weight distribution and a highly controlled structure. For example, methods include introducing stable covalent species called dormant species into the polymerization active site to suppress the deactivation of the active site without causing side reactions such as chain transfer reactions and quenching reactions. Examples of living polymerization include: those using free radicals as active species, those using cations as active species, and those using anions as active species. It is important to distinguish the systems based on the structure and properties of the polymerizable compound used. When obtaining the block polymer of polymer A used in the weakly anchored liquid crystal alignment film of the present invention, the polymerization method does not need to be particularly limited, but cationic polymerization and anionic polymerization are often used to generate active species. Alkali metals, Metal complexes and halogen compounds. In liquid crystal displays, the mixing of metal residues and halogen compounds may cause burn-in and display defects. Therefore, it is advisable to use radical polymerization that avoids the use of metals and halogen compounds as much as possible. Examples of living radical polymerization include: living radical polymerization (NMP) using nitrogen oxides as dormant species, atom transfer radical polymerization (ATRP) using metal complexes, and reversible addition-desorption using sulfur compounds as dormant species. Chain transfer polymerization (RAFT), living radical polymerization (TERP) using organic tellurium compounds, etc., reversible transfer catalytic polymerization (RTCP) using alkyl iodide compounds as dormant species and phosphorus compounds, alcohols, etc. as catalysts, etc. Ideal polymerization methods include living radical polymerization such as NMP, RTCP, and RAFT polymerization, with NMP or RAFT polymerization being particularly preferred.

When NMP is used, examples of the polymerization initiator used include: 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), Benzyl oxide, 1,1'-bis(tertiary butyl peroxide) cyclohexane, hydrogen peroxide, etc. The usage ratio of the polymerization initiator is usually 0.000001 to 0.1 mole part per 1 mole part of the monomer used, and preferably 0.00001 to 0.01 mole part. Examples of nitrogen oxides include compounds represented by the following formulas (N-1) to (N-12). The usage ratio of nitrogen oxide is usually 0.000001 to 0.1 mole part per 1 mole part of the monomer used, and preferably 0.00001 to 0.01 mole part. The reaction temperature during the above polymerization is preferably 20 to 200°C, more preferably 40 to 150°C, and the reaction time is preferably 1 to 168 hours, more preferably 8 to 72 hours.

[Chemical 48]

When RTCP is used, examples of polymerization initiators used include: 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), Benzyl oxide, 1,1'-bis(tertiary butyl peroxide) cyclohexane, hydrogen peroxide, etc. The usage ratio of the polymerization initiator is usually 0.000001 to 0.1 mole part per 1 mole part of the monomer used, and preferably 0.00001 to 0.01 mole part. Examples of the iodide catalyst include compounds represented by the following formulas (P-1) to (P-7). The usage ratio of the iodide catalyst is usually 0.000001 to 0.1 mole part relative to 1 mole part of the monomer used, and preferably 0.00001 to 0.01 mole part. Examples of the hydride catalyst include compounds represented by the following formulas (O-1) to (O-6). The usage ratio of the hydride catalyst is 0.000001 to 0.1 mole part relative to 1 mole part of the monomer used, preferably 0.00001 to 0.01 mole part. Generally, the reaction temperature during the above-mentioned polymerization is preferably 20 to 200°C, more preferably 40 to 150°C, and the reaction time is preferably 1 to 168 hours, more preferably 8 to 72 hours.

[Chemical 49] [Chemical 50]

When RAFT polymerization is used, examples of polymerization initiators used include: 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), Benzyl peroxide, 1,1'-bis(tertiary butyl peroxide) cyclohexane, hydrogen peroxide, etc. The usage ratio of the polymerization initiator is usually 0.000001 to 0.1 mole part per 1 mole part of the monomer used, and preferably 0.00001 to 0.01 mole part. Chain transfer agents (RAFT agents) are preferably trithiocarbonates, dithiobenzoates, dithiocarbamates, and xanthates. Specific examples include: the following formula (R-1 )～(R-23) represents the compound. The usage ratio of the chain transfer agent is usually 0.000001 to 0.1 mole part relative to 1 mole part of the monomer used, and preferably 0.00001 to 0.01 mole part. The reaction temperature during the above polymerization is preferably 20 to 200°C, more preferably 40 to 150°C, and the reaction time is preferably 1 to 168 hours, more preferably 8 to 72 hours.

[Chemistry 51]

The reason why RAFT polymerization exhibits active radical properties is because most of the active chains are dormant (resting type), and there are compounds that can reversibly inactivate the growing free radical species, and there are compounds between the active chains and dormant chains. There is a rapid balance between them.

By using RAFT polymerization, polymer terminal control, high-level molecular weight control, and molecular weight distribution control are possible.

In order to precisely synthesize functional polymers using RAFT polymerization, it is necessary to consider the reactivity of the monomers and select an appropriate chain transfer agent.

In RAFT polymerization, polymer terminals can be controlled by thermally or chemically modifying the RAFT terminals that have growing terminals. When thermally modified, the terminal can be modified into an unsaturated hydrocarbon group by heating above the temperature at which the RAFT agent used will thermally decompose. Moreover, when chemically modifying, the terminal can be modified into a thiol bond by contact with a primary amine, a secondary amine, etc., accompanied by aminolysis. In addition, new block segments can be set at the ends by contacting new monomers and free radical generators.

In RAFT polymerization, molecular weight control can be performed by using the following formula (eq1). Specifically, the number average molecular weight (Mn) changes linearly with the ratio of the molar concentration of the monomer to the molar concentration of the chain transfer agent, so the molecular weight can be controlled. [Number 1] In the above formula (eq1), Mn _(theor) represents the molecular weight of the polymer, [Monomer] ₀ represents the molar concentration of the monomer, [CTA] ₀ represents the molar concentration of the chain transfer agent, M _monomer represents the molecular weight of the monomer, conv. represents the polymerization conversion rate, and M _CTA represents the molecular weight of the chain transfer agent.

In addition, when the copolymer obtained by the above polymerization is dissolved in the reaction solution, the reaction solution can be directly supplied to the preparation of the liquid crystal alignment agent, or the copolymer contained in the reaction solution can be separated and then supplied to the liquid crystal alignment agent. Preparation of aligning agent.

The organic solvent used for the synthesis of the copolymer (polymer A) only needs to be one that does not chemically react with the compound species constituting the copolymer and does not capture free radicals. For example, N,N-dimethylformamide, N,N-dimethylacetamide, N,N-diethylformamide, N-methylformamide, N-methyl-2- Pyrrolidone, N-ethyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N-methylcaprolactam, N,N-diethyl acetamide, N ,N-Dipropylacetamide, 3-Methoxy-N,N-dimethylpropanamide, N,N-diethylpropanamide, diethylformamide, dimethylsulfoxide , tetramethylurea, pyridine, dimethylthione, hexamethylphosphatide, γ-butyrolactone, isopropyl alcohol, methoxymethylpentanol, dipentene, ethylpentyl ketone, methyl Nonyl Ketone, Methyl Ethyl Ketone, Methyl Isoamyl Ketone, Methyl Isopropyl Ketone, Methyl Cellulose, Ethyl Cellulose, Methyl Cellulose Acetate, Butyl Cellulose Acetate, ethyl cellulose acetate, diethylene glycol monobutyl ether, ethyl diethylene glycol monoethyl ether, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, Ethylene glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol tertiary butyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol, Diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol Monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether Propyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, dihexane, n-hexane, n-pentane, n-octane, 2-ethyl-1-hexanol, benzene, xylene, toluene, ethylbenzene, cumene, tertiary butylbenzene, tetrahydrofuran, diethyl ether, cyclohexanone, ethyl carbonate , propyl carbonate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl acetate, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate Ester, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, 3- Butyl methoxypropionate, diglyme, 4-hydroxy-4-methyl-2-pentanone, 3-methoxy-N,N-dimethylpropanamide, 3-ethyl Oxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, propyl pyruvate, butyl pyruvate, amyl pyruvate, hexyl pyruvate , 2-ethylhexyl pyruvate, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, amyl acetate, hexyl acetate, acetyl acetate -2-Ethylhexyl, methyl acetylpropionate, ethyl acetylpropionate, propyl acetylpropionate, butyl acetylpropionate, amyl acetylpropionate, hexyl acetylpropionate, 2-ethylhexyl acetate, dimethyl malonate, dimethyl succinate, dimethyl glutarate, dimethyl adipate, dimethyl phthalate, dimethyl maleate Methyl ester, diethyl malonate, diethyl succinate, diethyl glutarate, diethyl adipate, diethyl phthalate, diethyl maleate, dipropyl malonate , Dipropyl succinate, Dipropyl glutarate, Dipropyl adipate, Dipropyl phthalate, Dipropyl maleate, Dibutyl malonate, Dibutyl succinate, Glutaric acid Dibutyl acid, dibutyl adipate, dibutyl phthalate, dibutyl maleate, dipyl malonate, dipyl succinate, dipyl glutarate, dibutyl adipate Amyl ester, dipyl phthalate, dipyl maleate, dihexyl malonate, dihexyl succinate, dihexyl glutarate, dihexyl adipate, dihexyl phthalate , Dihexyl maleate, Di-2-ethylhexyl malonate, 2-ethylhexyl succinate, 2-ethylhexyl glutarate, 2-ethylhexyl adipate Ester, 2-ethylhexyl phthalate, 2-ethylhexyl maleate, etc. These organic solvents can be used individually or in mixture.

(Polymer B) Polymer B is a graft copolymer having a dendritic polymer that is compatible with liquid crystals and a dry polymer that is incompatible with liquid crystals or is incompatible with liquid crystals by calcination. In addition, the graft copolymer is insoluble in the liquid crystal due to the dry polymer or insoluble in the liquid crystal by calcination. The branch polymer is bonded to the dry polymer as a side chain of the dry polymer.

The applicant in this case found that the weakly anchored liquid crystal alignment agent containing polymer B can be easily manufactured and has good coating properties, and can obtain good adhesion with the sealant and can achieve it at the same time. A weakly anchored liquid crystal alignment agent for a weakly anchored liquid crystal alignment film that does not produce a pretilt angle, low-voltage driving, and high-speed response when the voltage is OFF, and filed an application (claimed Japanese Patent Application No. 2021-156886 and Japanese Patent Application No. 2021-156886 PCT/JP2022/35657 as priority. By citing this, the contents of these applications and publications are incorporated into this specification to the same extent as if fully expressly stated).

Graft copolymer is a general term for polymers with a branched structure, and refers to the polymerization of polymers that have both a "stem" corresponding to the polymer and a "branch" corresponding to the stem as a side chain bonded to the stem. things. The characteristic of one embodiment of the liquid crystal alignment agent of the present invention is that a graft copolymer is used as polymer B, but the graft copolymer has a dendritic polymer that is compatible with liquid crystals and is incompatible with liquid crystals or can be removed by calcination. Dry polymer compatible with liquid crystals. That is, the dendritic polymer compatible with the liquid crystal contributes to the formation of a weak anchor state by being compatible with the liquid crystal and swelling, while the graft copolymer is insoluble in the liquid crystal due to the dry polymer or insoluble in the liquid crystal by calcination. Liquid crystal, thereby preventing the graft copolymer from dissolving into the liquid crystal, and by fixing the substrate, cross-linking the polymers with each other, and cross-linking the sealant components, it is possible to obtain a film with excellent film hardness and sealant adhesion strength. Weak anchoring of liquid crystal display elements.

The structure of the dendritic polymer that is compatible with liquid crystals is not particularly limited as long as it is soluble in liquid crystals. For example, the dendritic polymer can be derived from a polymer monomer represented by the following formula (7).

[Chemistry 52] In formula (7), P represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and Q is obtained by polymerizing at least one monomer containing at least one of the compounds represented by formulas (2) to (5). In the obtained structure, n is an integer from 1 to 2. When n is 2, the two Qs can be the same or different.

The aforementioned monomer used in the synthesis of the branched polymer may be a single component, or a plurality of monomers may be used in combination. Furthermore, other radical polymerizable monomers described below may be used in combination.

Among polymer B used in weakly anchored liquid crystal alignment agents, dendritic polymers have a significant impact on the expression of weakly anchored properties. The physical properties of the weakly anchored film will change depending on the molecular weight of the branched polymer, so the optimization of the molecular weight is important. From the viewpoint of forming a good weakly anchored film, the ideal branch polymer has a molecular weight of 1,000 to 100,000, preferably 3,000 to 50,000. Molecular weight distribution expressed as the ratio of weight average molecular weight (Mw) to number average molecular weight (Mn) (PDI) is preferably below 3.0, preferably below 2.0. In addition, when the graft copolymer is synthesized by a macromonomer copolymerization grafting method using a polymer monomer, the molecular weight here is equivalent to the molecular weight of the polymer monomer.

In the branch polymer, the terminal structure (such as the structure of Q in formula (7)) is excluded, and for example, it may be a homopolymer structure using only one monomer represented by the above formulas (2) to (5), or It can be a copolymer structure combining multiple monomers. When a plurality of monomers are combined with each other, random copolymerization or block copolymerization may be performed. When the monomers represented by the above formulas (2) to (5) are combined with each other, the ratio is not particularly limited regardless of the combination method. When combined with the compound species described below that are insoluble in liquid crystals, from the viewpoint of maintaining properties, the ideal combination ratio of monomers that are insoluble in liquid crystals is 30 mol% or less, more preferably 20 mol% or less, but is not limited thereto. These synthesis methods, combined monomers, and combined ratios should be used within the range in which the intended physical properties, display characteristics, electrical characteristics, etc. can be obtained.

The dry polymer may contain, for example, the compound represented by the aforementioned formula (6) as a constituent component.

The polymer monomer represented by formula (7) as the raw material of the branch polymer forming the graft copolymer can be obtained, for example, by a combination of living polymerization, chain transfer polymerization, and polymer terminal modification reaction. Furthermore, it has been reported that a polymer having an unsaturated bond possessing radical polymerizability in the terminal group can be obtained by continuous block polymerization at a high temperature of 200°C or higher (East Asia Synthetic Research Annual Report TREND 2002 No. 5). Living polymerization refers to a polymerization reaction that is not accompanied by side reactions such as chain transfer reactions and stop reactions. It can obtain polymers with narrow molecular weight distribution and highly controlled structures. For example, methods include introducing stable covalent species called dormant species into the polymerization active site to suppress the deactivation of the active site without causing side reactions such as chain transfer reactions and quenching reactions. Living polymerization can include: those using free radicals as active species, those using cations as active species, and those using anions as active species. It is important to distinguish the systems according to the structure and properties of the monomers used. When obtaining the polymer monomer as the raw material of the graft copolymer, the polymerization method does not need to be particularly limited. However, when generating active species through cationic polymerization and anionic polymerization, alkali metals, metal complexes, and halogen compounds are often used. In liquid crystal displays, the mixing of metal residues, halogen compounds, etc. may cause burn-in and display defects, so it is advisable to use radical polymerization that uses as little metal or halogen compounds as possible. Examples of living radical polymerization include: nitrogen oxide mediated radical polymerization (NMP) using nitrogen oxides as dormant species, atom transfer radical polymerization (ATRP) using metal complexes, and reversible addition using sulfur compounds as dormant species. Formation-fragmentation chain transfer (RAFT) polymerization, living radical polymerization (TERP) using organic tellurium compounds, etc., reversible transfer catalytic polymerization (RTCP) using alkyl iodide compounds as dormant species and phosphorus compounds, alcohols, etc. as catalysts ), etc. Ideal polymerization methods include living radical polymerization such as NMP, RTCP, and RAFT polymerization. NMP or RAFT polymerization is particularly preferred.

The main synthesis methods of graft copolymers include: the grafting-to method of directly introducing branch polymers into dry polymers, and the monomers from polymer starters (dry polymers with polymerization active sites). Grafting-from method, which polymerizes and extends branched polymers, and macromonomer copolymerization-grafting (Grafting-from), which polymerizes macromolecular monomers (polymers with polymerizable functional groups at one end). Any method such as through) method can be used, so the synthesis method is not limited.

The method of producing the graft copolymer is not particularly limited, and a general method accepted in industry can be used. Specifically, it can be produced by using the aforementioned monomer and utilizing radical polymerization, cationic polymerization, or anionic polymerization. Among them, radical polymerization is particularly preferable from the viewpoint of ease of reaction control.

The polymerization initiator of free radical polymerization can use a free radical polymerization initiator (free radical thermal polymerization initiator, free radical photopolymerization initiator), or a reversible addition-fragmentation chain transfer (RAFT) polymerization reagent, etc. Well-known compounds.

The radical thermal polymerization initiator is a compound that generates free radicals by heating to a temperature higher than the decomposition temperature. Examples of such radical thermal polymerization initiators include ketone peroxides (methyl ethyl ketone peroxide, cyclohexanone peroxide, etc.), dihydroxyperoxides (acetyl peroxide, benzoyl peroxide, etc.) etc.), hydroperoxides (hydrogen peroxide, tertiary butyl hydroperoxide, cumene hydroperoxide, etc.), dialkyl peroxides (di(tertiary butyl peroxide), peroxide Dicumyl peroxide, dilauryl peroxide, etc.), peroxyketals (dibutylperoxycyclohexane, etc.), alkyl peroxyesters (tertiary butyl neodecanoate peroxide, tertiary butyl peroxide Tertiary butyl methyl acetate, tertiary amyl peroxy 2-ethylcyclohexanoate, etc.), persulfates (potassium persulfate, sodium persulfate, ammonium persulfate, etc.), azo compounds (azo compounds Azobisisobutyronitrile, 2,2'-bis(2-hydroxyethyl)azobisisobutyronitrile, etc.). One type of radical thermal polymerization initiator may be used alone, or two or more types may be used in combination.

The radical photopolymerization initiator is not particularly limited as long as it is a compound that starts radical polymerization by irradiation. Examples of such radical photopolymerization initiators include: benzophenone, Michelone, 4,4'-bis(diethylamino)benzophenone, cyclothiophenone, and 9-oxothioquinone , isopropyl ketone, 2,4-diethyl-9-oxothiothione , 2-ethylanthraquinone, acetophenone, 2-hydroxy-2-methylpropiophenone, 2-hydroxy-2-methyl-4'-isopropylpropiophenone, 1-hydroxycyclohexylphenylketone, isopropylphenone Probenzoin ether, isobutybenzoin ether, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, camphorquinone, benzanthrone, 2-Methyl-1-[4-(methylthio)phenyl]-2-𠰌linylpropan-1-one, 2-benzyl-2-dimethylamino-1-(4-𠰌 Phinyl phenyl)-1-butanone, 4-dimethylaminobenzoic acid ethyl ester, 4-dimethylaminobenzoic acid isoamyl ester, 4,4'-bis(tertiary butylperoxycarbonyl) ) benzophenone, 3,4,4'-tris(tertiary butylperoxycarbonyl)benzophenone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2-( 4'-Methoxystyrene)-4,6-bis(trichloromethyl)tristriene, 2-(3',4'-dimethoxystyrene)-4,6-bis(trichloro Methyl) mesostyrene, 2-(2',4'-dimethoxystyrene)-4,6-bis(trichloromethyl) mesostyrene, 2-(2'-methoxystyrene) )-4,6-bis(trichloromethyl)strisene, 2-(4'-pentyloxystyrene)-4,6-bis(trichloromethyl)sesne, 4-[p -N,N-bis(ethoxycarbonylmethyl)]-2,6-bis(trichloromethyl)mesotriene, 1,3-bis(trichloromethyl)-5-(2'-chloro Phenyl) mesene, 1,3-bis(trichloromethyl)-5-(4'-methoxyphenyl) mesene, 2-(p-dimethylaminostyrene) benzo Azole, 2-(p-dimethylaminostyrene)benzothiazole, 2-mercaptobenzothiazole, 3,3'-carbonylbis(7-diethylaminocoumarin), 2-(o-chloro Phenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2-chlorophenyl)-4,4',5,5'- 4(4-ethoxycarbonylphenyl)-1,2'-biimidazole, 2,2'-bis(2,4-dichlorophenyl)-4,4',5,5'-tetraphenyl -1,2'-biimidazole, 2,2'-bis(2,4-dibromophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2, 2'-bis(2,4,6-trichlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 3-(2-methyl-2-bis Methylaminopropyl)carbazole, 3,6-bis(2-methyl-2-𠰌linylpropyl)-9-n-dodecylcarbazole, 1-hydroxycyclohexylphenylketone , bis(5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl)titanium, 3,3', 4,4'-four (tertiary butyl peroxycarbonyl) benzophenone, 3,3',4,4'-four (tertiary hexyl peroxycarbonyl) benzophenone, 3,3'-bis (Methoxycarbonyl)-4,4'-bis(tertiary butylperoxycarbonyl)benzophenone, 3,4'-bis(methoxycarbonyl)-4,3'-bis(tertiary butyl) methylperoxycarbonyl)benzophenone, 4,4'-bis(methoxycarbonyl)-3,3'-bis(tertiary butylperoxycarbonyl)benzophenone, 2-(3-methyl -3H-benzothiazole-2-ylidene)-1-naphthalen-2-yl-ethanone, 2-(3-methyl-1,3-benzothiazole-2(3H)-ylidene)-1 -(2-benzoyl)ethanone, etc. A radical photopolymerization initiator may be used individually by 1 type, and may be used in mixture of 2 or more types.

The radical polymerization method is not particularly limited, and emulsion polymerization, suspension polymerization, dispersion polymerization, precipitation polymerization, block polymerization, solution polymerization, etc. can be used. The organic solvent used in the radical polymerization reaction is not particularly limited as long as it can dissolve the produced polymer. Specific examples thereof include: N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-methyl -ε-Caprolactamide, N,N-diethyl acetamide, N,N-dipropylacetamide, 3-methoxy-N,N-dimethylpropanamide, N,N - Diethylpropamide, diethylformamide, dimethyltrisoxide, tetramethylurea, pyridine, dimethyltrisine, hexamethylphosphoramide, γ-butyrolactone, isopropyl alcohol, Methoxymethylpentyl alcohol, dipentene, ethyl amyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isopentyl ketone, methyl isopropyl ketone, methylcellulose, Ethyl cellulsue, methyl cellulsue acetate, ethyl cellulsue acetate, diethylene glycol monobutyl ether, ethyl diethylene glycol monoethyl ether, ethylene glycol, ethylene glycol monoethyl Acid ester, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether (butyl cellulose), propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monotertiary butyl ether, diethylene glycol, Diethylene glycol monoacetate, diethylene glycol dimethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol mono Propyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether Ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, 1,4-dioxane, n-hexane, n-pentane, n-octane, cyclohexane, benzene, xylene, toluene, ethylbenzene, cumene, tertiary butylbenzene, tetrahydrofuran, diethyl ether, cyclohexanone, ethyl carbonate, ethyl carbonate Propyl ester, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, 3 -Ethyl methoxypropionate, 3-ethoxypropionate, 3-methoxypropionate, propyl 3-methoxypropionate, butyl 3-methoxypropionate, diethylene glycol di Methyl ether, 4-hydroxy-4-methyl-2-pentanone, 3-methoxy-N,N-dimethylpropanamide, 3-ethoxy-N,N-dimethylpropanamide , 3-Butoxy-N,N-dimethylpropanamide, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, amyl pyruvate, hexyl pyruvate, pyruvate -2-Ethylhexyl, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, amyl acetate, hexyl acetate, acetate-2- Ethylhexyl, methyl acetylpropionate, ethyl acetylpropionate, propyl acetylpropionate, butyl acetylpropionate, amyl acetylpropionate, hexyl acetylpropionate, acetylpropionate Acid-2-ethylhexyl, dimethyl malonate, dimethyl succinate, dimethyl glutarate, dimethyl adipate, dimethyl phthalate, dimethyl maleate, Diethyl malonate, diethyl succinate, diethyl glutarate, diethyl adipate, diethyl phthalate, diethyl maleate, dipropyl malonate, succinic acid Dipropyl ester, dipropyl glutarate, dipropyl adipate, dipropyl phthalate, dipropyl maleate, dibutyl malonate, dibutyl succinate, dibutyl glutarate Ester, dibutyl adipate, dibutyl phthalate, dibutyl maleate, dipyl malonate, dipyl succinate, dipyl glutarate, dipyl adipate, Dipentyl phthalate, dipyl maleate, dihexyl malonate, dihexyl succinate, dihexyl glutarate, dihexyl adipate, dihexyl phthalate, maleic acid Dihexyl acid, di-2-ethylhexyl malonate, 2-ethylhexyl succinate, 2-ethylhexyl glutarate, 2-ethylhexyl adipate, benzene 2-ethylhexyl dicarboxylate, 2-ethylhexyl maleate, etc. These organic solvents may be used individually by 1 type, and may be used in mixture of 2 or more types.

In addition, even if it is a solvent that cannot dissolve the produced polymer, it can be mixed with the above-mentioned organic solvent and used as long as the produced polymer does not precipitate. In addition, in radical polymerization, oxygen in the organic solvent may hinder the polymerization reaction, so it is preferable to use an organic solvent that is degassed as much as possible. In addition, when the graft copolymer obtained by the above polymerization is dissolved in the reaction solution, the reaction solution can be directly supplied to the preparation of the liquid crystal alignment agent, or the graft copolymer contained in the reaction solution can be separated. , and then supplied to the preparation of liquid crystal alignment agent. The polymerization temperature during radical polymerization can be selected from any temperature ranging from 30 to 150°C, and is preferably in the range of 50 to 100°C. In addition, the reaction can be carried out at any concentration. If the concentration is too low, it will be difficult to obtain a high molecular weight polymer. If the concentration is too high, the viscosity of the reaction solution will become too high and it will be difficult to stir evenly. Therefore, the monomer concentration is preferably 1 to 50 mass%, more preferably 5 to 40 mass%. It can also be carried out at a high concentration in the initial stage of the reaction, and then the organic solvent can be added.

In the above-mentioned free radical polymerization reaction, if the ratio of the free radical polymerization initiator to the monomer is larger, the molecular weight of the polymer obtained will become smaller. If it is smaller, the molecular weight of the polymer obtained will become larger, so the free radical The ratio of the initiator to the monomer to be polymerized is preferably 0.1 to 10 mol%. In addition, various monomer components, solvents, initiators, etc. may be added during polymerization.

The polymer produced from the reaction solution obtained by the above reaction can be recovered by pouring the reaction solution into a poor solvent and precipitating it, but this reprecipitation treatment is not necessary. Examples of poor solvents used for precipitation include: methanol, acetone, hexane, heptane, butylcellulose, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, diethyl ether, methyl ethyl ether, water etc. The polymer precipitated by being put into a poor solvent can be filtered and recovered, and then dried under normal pressure or reduced pressure, at normal temperature or by heating. In addition, if the recovered polymer is redissolved in an organic solvent and the reprecipitation recovery operation is repeated 2 to 10 times, the impurities in the polymer can be reduced. Examples of poor solvents in this case include alcohols, ketones, hydrocarbons, etc. It is preferable to use three or more types of poor solvents selected from these because the purification efficiency will be further improved.

The graft copolymer preferably has a weight average molecular weight of 2,000 to 5,000,000, measured by the GPC (Gel Permeation Chromatography) method, taking into account the strength of the coating film obtained, the workability during coating film formation, and the uniformity of the coating film. 2,000,000 is better.

Graft copolymers are characterized by having a dendritic polymer that is compatible with liquid crystals and a dry polymer that is incompatible with liquid crystals or incompatible by heat, etc., and they are connected in a random arrangement through free radical polymerization. This enables high sealing adhesion, solvent selectivity, and coating properties.

In order to take into account the coating properties, sealing adhesion, film strength, and good weak anchoring characteristics of the weakly anchored liquid crystal alignment film, the introduction ratio of branched polymers to dry polymers is also an important condition. For example, branch polymers play an important role in terms of weak anchoring properties. If they are introduced in a large proportion, they will impair the strength of the film or hinder thermal hardening, so it is necessary to consider the appropriate introduction amount. On the other hand, the introduction amount and molecular weight of the dry polymer have no influence (little influence) on the weak anchoring properties. Therefore, in order to take into account the aforementioned properties, it is advisable to use the polymer represented by formula (1) for the synthesis of the branched polymer. The ratio (introduction ratio) of the number of molecules of the monomer to the number of molecules of the monomer represented by formula (8) used for synthesis of the dry polymer is small. The ideal introduction ratio (polymer represented by formula (1)/monomer represented by formula (8)) is 0.1/99.9 to 50/50 (mol/mol), and 0.2/99.8 to 30/70 ( Mol/mol) is better.

(Polymer C) Polymer C is a polymer having polymer units compatible with liquid crystals, and is a polymer that reacts with the aforementioned polymer having a structural unit represented by formula (1) by heating. Polymer C is a polymer that has a group that reacts with the polymer (RSM) by heating and is a polymer obtained by polymerizing one or more monomers that are compatible with liquid crystals. The characteristic is that it reacts with liquid crystals in a thin film state If in contact, it will be compatible with the liquid crystal and contribute to the formation of a weak anchoring state.

The applicant of this case found that a weakly anchored liquid crystal alignment agent containing a polymer such as polymer C (a polymer that has polymer units that are compatible with liquid crystals and will react with other polymers used in combination) can be easily The weakly anchored liquid crystal alignment agent is manufactured and has good coating properties, and has good adhesion with the sealant, and can provide weak anchoring that can simultaneously achieve no pretilt angle, low voltage driving and high-speed response when the voltage is OFF. Liquid crystal alignment film, and filed an application (PCT/JP2023/1515 claiming Japanese Patent Application No. 2022-6921 and Japanese Patent Application No. 2022-6921 as priority). By citing this, these applications are incorporated to the same extent as if fully expressly stated. and the contents of public gazettes are incorporated into this manual).

Polymer C is a polymer represented by the following formula (8).

[Chemistry 53] In formula (8), A represents a polymer selected from the following formulas (8-A-1) to (8-A-16) that reacts with the aforementioned polymer having a structural unit represented by formula (1) by heating. An n-valent organic radical with a molecular weight of less than 300. Q is a divalent polymer unit compatible with liquid crystals containing at least one selected from the group consisting of the compounds represented by the aforementioned formulas (2) to (5) as a constituent component. R is 1 selected from the following formulas (8-R-1) to (8-R-11) with a molecular weight of 500 or less that does not react with the polymer having the structural unit represented by formula (1) by heating. Valence organic base. n is an integer between 1 and 2. When n is 2, the two Q and R can be the same or different respectively.

[Chemistry 54] In formulas (8-A-1) to (8-A-16), R ₁ and R ₂ each independently represent a hydrogen atom or a linear or branched alkyl group with 1 to 12 carbon atoms, and R ₃ and R ₄ each independently represent G represents a single bond or a linear or branched alkylene group having 1 to 12 carbon atoms, and X represents an oxygen atom or a sulfur atom. *Indicates the bonding part.

[Chemical 55] In formulas (8-R-1) to (8-R-11), R ₁ and R ₂ each independently represent a hydrogen atom or a linear or branched alkyl group with 1 to 12 carbon atoms, and R ₃ and R ₄ each independently represent represents a single bond or a linear or branched alkylene group having 1 to 12 carbon atoms. *Indicates the bonding part. The number of carbon atoms in a linear or branched alkyl group having 1 to 12 carbon atoms depends on each group, and the ideal range thereof varies. For example, it may be 1 to 6 or 6 to 12. The carbon number of the linear or branched alkylene group having 1 to 12 carbon atoms may be, for example, 1 to 6, or 1 to 3.

The molecular weight of A in formula (8) is not particularly limited, but is preferably 300 or less. The molecular weight of R in formula (8) is not particularly limited, but is preferably 500 or less.

A in the formula (8) is a group selected from the above formulas (8-A-1) to (8-A-16). These are, for example, substructures of a RAFT agent in RAFT polymerization described later and a chain transfer agent in chain transfer polymerization. For example, -S-C(=S)-group will combine with amine group, protected amine group, hydroxyl group, protected hydroxyl group, thiol group, protected thiol group, carboxyl group, protected carboxyl group, isocyanate group, protected isocyanate group, maleimide group, carboxylic acid anhydride group, vinyl group, allyl group, styrene group, (meth)acrylic acid group, and (meth)acrylamide group, etc. to react. The carbon number of the linear or branched alkyl group having 1 to 12 carbon atoms may be, for example, 1 to 6, or 1 to 3. The carbon number of the linear or branched alkylene group having 1 to 12 carbon atoms may be, for example, 1 to 6, or 1 to 3.

R in formula (8) is a group selected from the group consisting of the above formulas (8-R-1) to (8-R-11). These are, for example, secondary structures of the RAFT agent in RAFT polymerization described below.

Q in the formula (8) preferably contains at least one selected from the group consisting of the compounds represented by the aforementioned formulas (2) to (5) as a constituent component.

The monomer used in the synthesis of polymer C may be a single component, or a plurality of monomers may be used in combination. In addition, other radically polymerizable monomers described below may be used in combination.

When polymer C contacts liquid crystal in a thin film state, it will form a polymer-liquid crystal hybrid layer and exhibit weak anchoring. Depending on the molecular weight of polymer C, the thickness of the polymer-liquid crystal mixed layer formed will also change, and the weak anchorage will also change, so the optimization of the molecular weight is important. From the viewpoint of forming a good weakly anchored film, the ideal molecular weight of polymer C is 1,000 to 100,000, more preferably 3,000 to 50,000. The molecular weight distribution is represented by the ratio of weight average molecular weight (Mw) to number average molecular weight (Mn) ( PDI), it is better to be below 3.0, and preferably below 2.0.

The structure of Q in the polymer constituting polymer C may be a homopolymer structure using only the compounds (monomers) represented by the above formulas (2) to (5), or may be a combination of multiple monomers. copolymer structure. When a plurality of monomers are combined with each other, random copolymerization or block copolymerization may be performed. When the monomers represented by the above formulas (2) to (5) are combined with each other, the ratio is not particularly limited regardless of the combination method. When combined with the compound species insoluble in liquid crystal described below, from the viewpoint of maintaining properties, the ideal combination ratio of the compound species insoluble in liquid crystal is 30 mol% or less, more preferably 20 mol% or less, but is not limited thereto. These synthesis methods, combined monomers, and combined ratios should be used within the range in which the intended physical properties, display characteristics, electrical characteristics, etc. can be obtained.

Examples of compound species insoluble in liquid crystals include: the compound represented by the aforementioned formula (6), the aforementioned compound having a polymerizable group having a polymerizable unsaturated hydrocarbon group and a highly polar structure, and the aforementioned compound having a polymerizable unsaturated hydrocarbon group. A compound with a polymerizable group and a rigid structure, the aforementioned compound having a polymerizable group with a polymerizable unsaturated hydrocarbon group and a thermosetting structure.

Polymer C is preferably obtained by living polymerization or chain transfer polymerization.

Living polymerization refers to a polymerization reaction that is not accompanied by side reactions such as chain transfer reactions and stop reactions. It can obtain polymers with narrow molecular weight distribution and highly controlled structures. For example, methods include introducing stable covalent species called dormant species into the polymerization active site to suppress the deactivation of the active site without causing side reactions such as chain transfer reactions and quenching reactions. Living polymerization can include: those using free radicals as active species, those using cations as active species, and those using anions as active species. It is important to distinguish the systems according to the structure and properties of the monomers used.

When obtaining polymer C, the polymerization method does not need to be particularly limited. However, cationic polymerization and anionic polymerization are used to generate active species. Alkali metals, metal complexes, and halogen compounds are often used. In liquid crystal displays, metal residues, The mixing of halogen compounds and the like may cause burn-in and display defects, so it is advisable to use radical polymerization that uses as little metal or halogen compounds as possible. Examples of living radical polymerization include: living radical polymerization (NMP) using nitrogen oxides as dormant species, atom transfer radical polymerization (ATRP) using metal complexes, and reversible addition-fragmentation using sulfur compounds as dormant species. Chain transfer polymerization (RAFT polymerization), living radical polymerization (TERP) using organic tellurium compounds, etc., reversible transfer catalytic polymerization (RTCP) using iodinated alkyl compounds as dormant species and phosphorus compounds, alcohols, etc. as catalysts etc. Ideal polymerization methods include living radical polymerization such as NMP, RTCP, and RAFT polymerization, and NMP or RAFT polymerization is particularly preferred. Alternatively, chain transfer polymerization may be used.

When chain transfer polymerization is used, examples of the polymerization initiator used include: 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile) , benzoyl peroxide, 1,1'-bis(tertiary butyl peroxide) cyclohexane, hydrogen peroxide, etc. The usage ratio of the polymerization initiator is usually 0.000001 to 0.1 mole part per 1 mole part of the monomer used, and preferably 0.00001 to 0.01 mole part. As the chain transfer agent, mercaptans are preferably used, and specific examples thereof include compounds represented by the following formulas (S-1) to (S-15). The usage ratio of the chain transfer agent is usually 0.000001 to 0.1 mole part relative to 1 mole part of the monomer used, and preferably 0.00001 to 0.01 mole part. The reaction temperature during the above polymerization is preferably 20 to 200°C, more preferably 40 to 150°C, and the reaction time is preferably 1 to 168 hours, more preferably 8 to 72 hours.

[Chemical 56] Me represents methyl group, and Et represents ethyl group.

By using chain transfer polymerization, polymer terminal control, molecular weight control, and molecular weight distribution control can be performed.

In chain transfer polymerization, polymers can be obtained by competing reactions between chain transfer and growth reactions. The molecular weight and molecular weight distribution of the polymer obtained by chain transfer polymerization depend on the chain transfer constant (Cs) represented by the quotient of the chain transfer rate constant (kc) and the growth rate constant (kp). Generally, in chain transfer polymerization, a composition in which Cs is in the range of 1 to 60 is preferable. The type of monomers and chain transfer agents used, and their correct combination are important.

The chain transfer constant (Cs) varies greatly depending on the type of monomer and chain transfer agent used, so it needs to be selected correctly.

The polymer constituting the polymer C should preferably be composed of one or more compound species that are compatible with liquid crystals from the viewpoint of maintaining properties. However, a small amount of compound species that are incompatible with liquid crystals or are insoluble in liquid crystals by calcination may also be used. Can be imported. The ideal combination ratio of monomers insoluble in liquid crystal is 30 mol% or less, more preferably 20 mol% or less, but is not limited thereto. These synthesis methods, combined monomers, and combined ratios should be used within the range in which the intended physical properties, display characteristics, electrical characteristics, etc. can be obtained.

One embodiment of the polymer alloy of the present invention is characterized by containing: having a group that reacts with a polymer (RSM) by heating and obtained by polymerizing one or more monomers that are compatible with liquid crystals Polymer C composed of a polymer, and a polymer (RSM) that reacts with the polymer C by heating to suppress elution of the polymer C into the liquid crystal. This enables high sealing adhesion, solvent selectivity, and coating properties.

In one example, the group in the polymer C that reacts with the polymer (RSM) by heating, and the n-valent organic group A in the polymer (RSM) that reacts with the polymer C by heating The temperature at which the reaction takes place is not particularly limited. For example, it may be 150°C or higher or 200°C or higher.

The polymer alloy of the present invention is characterized by containing: polymer A and polymer B or polymer C as components showing weak anchoring properties; and a polymer (RSM) that has a viscosity increasing effect and a coating property improving effect of a varnish. . This enables high solvent selectivity and coating properties.

The heating temperature of the polymer alloy of the present invention is not particularly limited, and may be, for example, 150°C or higher or 200°C or higher.

In order to take into account the coating properties, sealing adhesion, film strength, and good weak anchoring characteristics of the weakly anchored liquid crystal alignment film, it is necessary to use components and polymers (RSM) that exhibit weak anchorage together. In addition, the mixing ratio of the component exhibiting weak anchoring properties to the polymer (RSM) is an important condition. For example, in terms of weak anchoring properties, components exhibiting weak anchoring properties play an important role. If they are introduced in a large proportion, they will impair the strength of the film or hinder thermal hardening, so it is necessary to consider the appropriate introduction amount. On the other hand, the introduction amount and molecular weight of the polymer (RSM) component have no influence (little influence) on the weak anchoring properties. Therefore, in order to ideally take into account the aforementioned properties, it is appropriate to make the component exhibiting weak anchoring relative to the polymer (RSM). RSM) polymer has a small mass ratio. The mass ratio (component exhibiting weak anchoring/polymer (RSM)) is preferably 0.1/99.9~99.1/0.1 (mass ratio), more preferably 1.0/99.0~99.0/1.0 (mass ratio), 10/90~ 90/10 (quality ratio) is excellent. The mass ratio (polymer A/polymer (RSM)) is preferably 10/90 to 90/10 (mass ratio), more preferably 30/70 to 80/20 (mass ratio). The mass ratio (polymer B/polymer (RSM)) is preferably 0.1/99.9 to 50/50 (mass ratio), more preferably 1.0/99.0 to 40/60 (mass ratio). The mass ratio (polymer C/polymer (RSM)) is preferably 0.1/99.9 to 50/50 (mass ratio), more preferably 1.0/99.0 to 40/60 (mass ratio).

(Weakly anchored liquid crystal alignment agent) The weakly anchored liquid crystal alignment agent is used in the formation of the aforementioned liquid crystal alignment film in a liquid crystal cell having a liquid crystal and a liquid crystal alignment film. In the liquid crystal alignment agent, the composite component other than the polymer (RSM) constituting the alignment film and the component exhibiting weak anchorage can be a monomer or a polymer. When selecting a polymer as a composite component, multiple polymers can be mixed and used. In addition, the polymer used for compounding may include polymers such as polyamide acid, polyimide, polyamide ester, polyamide, polyester, polyurea, polyacrylate, and polyorganosiloxane. It can also contain silane coupling agent, other additives, etc. From the viewpoint of improving electrical characteristics and reliability, it is advisable to combine components different from those of the above-mentioned polymer alloys, and it is particularly preferable to use polyamide acid, polyimide, etc. in combination. The compounding ratio of the polymer compounded with the polymer alloy is not particularly limited. From the viewpoint of optical properties and processability, the ideal compounding ratio (the ratio of the compounding component to the total of the polymer alloy and the compounding component) is 99 mass% or less, more preferably 70 mass% or less. Regarding the additives, there is no particular limit on the amount added. When a monomer is selected as a composite component, a plurality of monomers can also be mixed and used. In addition, the monomer used for compounding is preferably a polyfunctional (meth)acrylate, a polyfunctional epoxide, a polyfunctional ethylene, or the like that exhibits thermosetting properties. It is also possible to use a thermal acid generator and a thermal alkali in combination at the same time. Generators, thermal free radical generators, etc. The compounding ratio of the monomers compounded with the polymer alloy is not particularly limited. From the viewpoint of optical properties and processability, the ideal compounding ratio is 99 mass% or less, and more preferably 70 mass% or less.

When polyamic acid or polyimide is used as a composite component, diamine components used in the synthesis of polyamic acid or polyimide include the following diamines. Specific examples include: p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, m-phenylenediamine, 2,4-dimethyl-m-p-phenylenediamine Phenylenediamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,5-diaminophenol, 2,4-diaminophenol, 3,5-diaminophenol, 3 ,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, 4,4'-diaminobiphenyl, 3,3'-dimethyl -4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl Benzene, 3,3'-dicarboxy-4,4'-diaminobiphenyl, 3,3'-difluoro-4,4'-diaminobiphenyl, 3,3'-bis(trifluoromethyl base)-4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,2'-diaminobiphenyl, 2,3 '-Diaminobiphenyl, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 2,2 '-Diaminodiphenylmethane, 2,3'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 3 ,4'-diaminodiphenyl ether, 2,2'-diaminodiphenyl ether, 2,3'-diaminodiphenyl ether, 4,4'-sulfonyl diphenylamine, 3 ,3'-sulfonyl diphenylamine, bis(4-aminophenyl)silane, bis(3-aminophenyl)silane, dimethylbis(4-aminophenyl)silane, dimethylbis (3-Aminophenyl)silane, 4,4'-thiodiphenylamine, 3,3'-thiodiphenylamine, 4,4'-diaminodiphenylamine, 3,3'-diamine diphenylamine, 3,4'-diaminodiphenylamine, 2,2'-diaminodiphenylamine, 2,3'-diaminodiphenylamine, N-methyl( 4,4'-diaminodiphenyl)amine, N-methyl(3,3'-diaminodiphenyl)amine, N-methyl(3,4'-diaminodiphenyl) Amine, N-methyl(2,2'-diaminodiphenyl)amine, N-methyl(2,3'-diaminodiphenyl)amine, 4,4'-diaminodiphenyl Methone, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, 2,2'-diaminobenzophenone, 2,3'-diaminobenzophenone Benzophenone, 1,4-diaminonaphthalene, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 1,8-diaminonaphthalene, 2,5-diaminonaphthalene, 2,6-diaminonaphthalene, 2,7-diaminonaphthalene, 1,2-bis(4-aminophenyl)ethane, 1,2-bis(3 -Aminophenyl)ethane, 1,3-bis(4-aminophenyl)propane, 1,3-bis(3-aminophenyl)propane, 1,4-bis(4-aminophenyl)propane ethyl)butane, 1,4-bis(3-aminophenyl)butane, bis(3,5-diethyl-4-aminophenyl)methane, 1,4-bis(4-amino) Phenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl) Benzene, 1,4-bis(4-aminobenzyl)benzene, 1,3-bis(4-aminophenoxy)benzene, 4,4'-[1,4-phenylenebis(methylene) base)] diphenylamine, 4,4'-[1,3-phenylene bis (methylene)] diphenylamine, 3,4'-[1,4-phenylene bis (methylene)] di Aniline, 3,4'-[1,3-phenylenebis(methylene)]diphenylamine, 3,3'-[1,4-phenylenebis(methylene)]diphenylamine, 3, 3'-[1,3-phenylenebis(methylene)]diphenylamine, 1,4-phenylenebis[(4-aminophenyl)methanone], 1,4-phenylenebis[(4-aminophenyl)methanone] [(3-Aminophenyl)methanone], 1,3-phenylenebis[(4-aminophenyl)methanone], 1,3-phenylenebis[(3-aminophenyl) )methanone], 1,4-phenylenebis(4-aminobenzoate), 1,4-phenylenebis(3-aminobenzoate), 1,3-phenylenebis(3-aminobenzoate) Bis(4-aminobenzoate), 1,3-phenylenebis(3-aminobenzoate), bis(4-aminophenyl)terephthalate, bis(3 -Aminophenyl)terephthalate, bis(4-aminophenyl)isophthalate, bis(3-aminophenyl)isophthalate, N,N'- (1,4-phenylene)bis(4-aminobenzamide), N,N'-(1,3-phenylene)bis(4-aminobenzamide), N,N '-(1,4-phenylene)bis(3-aminobenzamide), N,N'-(1,3-phenylene)bis(3-aminobenzamide), N ,N'-bis(4-aminophenyl)terephthalamide, N,N'-bis(3-aminophenyl)terephthalamide, N,N'-bis(4- Aminophenyl)isophthalamide, N,N'-bis(3-aminophenyl)isophthalamide, 9,10-bis(4-aminophenyl)anthracene, 4, 4'-bis(4-aminophenoxy)diphenylsine, 2,2'-bis[4-(4-aminophenoxy)phenyl]propane, 2,2'-bis[4- (4-Aminophenoxy)phenyl]hexafluoropropane, 2,2'-bis(4-aminophenyl)hexafluoropropane, 2,2'-bis(3-aminophenyl)hexafluoropropane Propane, 2,2'-bis(3-amino-4-methylphenyl)hexafluoropropane, 2,2'-bis(4-aminophenyl)propane, 2,2'-bis(3- Aminophenyl)propane, 2,2'-bis(3-amino-4-methylphenyl)propane, trans-1,4-bis(4-aminophenyl)cyclohexane, 3, 5-Diaminobenzoic acid, 2,5-diaminobenzoic acid, bis(4-aminophenoxy)methane, 1,2-bis(4-aminophenoxy)ethane, 1,3 -Bis(4-aminophenoxy)propane, 1,3-bis(3-aminophenoxy)propane, 1,4-bis(4-aminophenoxy)butane, 1,4- Bis(3-aminophenoxy)butane, 1,5-bis(4-aminophenoxy)pentane, 1,5-bis(3-aminophenoxy)pentane, 1,6 -Bis(4-aminophenoxy)hexane, 1,6-bis(3-aminophenoxy)hexane, 1,7-bis(4-aminophenoxy)heptane, 1, 7-bis(3-aminophenoxy)heptane, 1,8-bis(4-aminophenoxy)octane, 1,8-bis(3-aminophenoxy)octane, 1 ,9-bis(4-aminophenoxy)nonane, 1,9-bis(3-aminophenoxy)nonane, 1,10-bis(4-aminophenoxy)decane, 1,10-bis(3-aminophenoxy)decane, 1,11-bis(4-aminophenoxy)undecan, 1,11-bis(3-aminophenoxy)decane Aromatic diamines such as monoalkane, 1,12-bis(4-aminophenoxy)dodecane, 1,12-bis(3-aminophenoxy)dodecane; bis(4-amino) Alicyclic diamines such as cyclohexyl)methane and bis(4-amino-3-methylcyclohexyl)methane; 1,3-diaminopropane, 1,4-diaminobutane, 1,5- Diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10- Aliphatic diamines such as diaminodecane, 1,11-diaminoundecane, and 1,12-diaminododecane; 1,3-bis[2-(p-aminophenyl)ethyl ]urea, 1,3-bis[2-(p-aminophenyl)ethyl]-1-tertiary butoxycarbonyl urea and other diamines with urea structure; N-p-aminophenyl-4-p Aminophenyl (tertiary butoxycarbonyl) aminomethylpiperidine and other diamines with nitrogen-containing unsaturated heterocyclic structures; N-tertiary butoxycarbonyl-N-(2-(4-amino Diamines having an N-Boc group (Boc represents tertiary butoxycarbonyl), etc., such as phenyl)ethyl)-N-(4-aminobenzyl)amine, etc.

The above-mentioned diamine can be used alone or in combination of two or more types. The tetracarboxylic dianhydride reacted with the above diamine component is not particularly limited. Specific examples include: pyromellitic acid, 2,3,6,7-naphthalene tetracarboxylic acid, 1,2,5,6-naphthalene tetracarboxylic acid, 1,4,5,8-naphthalene tetracarboxylic acid, 2,3,6 ,7-anthracenetetracarboxylic acid, 1,2,5,6-anthracenetetracarboxylic acid, 3,3',4,4'-biphenyltetracarboxylic acid, 2,3,3',4'-biphenyltetracarboxylic acid, bis (3,4-dicarboxyphenyl) ether, 3,3',4,4'-benzophenonetetracarboxylic acid, bis(3,4-dicarboxyphenyl)terine, bis(3,4-dicarboxylic acid) Phenyl)methane, 2,2-bis(3,4-dicarboxyphenyl)propane, 1,1,1,3,3,3-hexafluoro-2,2-bis(3,4-dicarboxybenzene) methyl)propane, bis(3,4-dicarboxyphenyl)dimethylsilane, bis(3,4-dicarboxyphenyl)diphenylsilane, 2,3,4,5-pyridinetetracarboxylic acid, 2, 6-Bis(3,4-dicarboxyphenyl)pyridine, 3,3',4,4'-diphenyltetracarboxylic acid, 3,4,9,10-perylenetetracarboxylic acid, 1,3-diphenyl 1,2,3,4-cyclobutanetetracarboxylic acid, oxydiphthalotetracarboxylic acid, 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid , 1,2,4,5-cyclohexanetetracarboxylic acid, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,2-dimethyl-1 ,2,3,4-cyclobutanetetracarboxylic acid, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cycloheptanetetracarboxylic acid, 2 ,3,4,5-Tetrahydrofurantetracarboxylic acid, 3,4-dicarboxy-1-cyclohexylsuccinic acid, 2,3,5-tricarboxycyclopentylacetic acid, 3,4-dicarboxy-1,2,3 ,4-tetrahydro-1-naphthalenesuccinic acid, bicyclo[3.3.0]octane-2,4,6,8-tetracarboxylic acid, bicyclo[4.3.0]nonane-2,4,7,9-tetracarboxylic acid Formic acid, bicyclo[4.4.0]decane-2,4,7,9-tetracarboxylic acid, bicyclo[4.4.0]decane-2,4,8,10-tetracarboxylic acid, tricyclo[6.3.0.0<2 ,6>]Undecane-3,5,9,11-tetracarboxylic acid, 1,2,3,4-butanetetracarboxylic acid, 4-(2,5-dilateral oxytetrahydrofuran-3-yl)- 1,2,3,4-Tetralin-1,2-dicarboxylic acid, bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic acid, 5-(2,5-dicarboxylic acid Side oxytetrahydrofuryl)-3-methyl-3-cyclohexane-1,2-dicarboxylic acid, tetracyclo[6.2.1.1.0<2,7>]dodecane-4,5,9,10 -Dianhydrides of tetracarboxylic acids such as tetracarboxylic acid, 3,5,6-tricarboxynorbornane-2:3,5:6dicarboxylic acid, and 1,2,4,5-cyclohexanetetracarboxylic acid.

Of course, tetracarboxylic dianhydride may be used alone or in combination of two or more types.

When the polymer is a polyamide ester, the structure of the dialkyl tetracarboxylate reacted with the diamine component is not particularly limited, and specific examples thereof are as follows. Specific examples of aliphatic tetracarboxylic acid diesters include: 1,2,3,4-cyclobutanetetracarboxylic acid dialkyl ester, 1,2-dimethyl-1,2,3,4-cyclobutane Dialkyl tetracarboxylate, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic acid dialkyl ester, 1,2,3,4-tetramethyl-1,2,3 ,4-cyclobutanetetracarboxylic acid dialkyl ester, 1,2,3,4-cyclopentanetetracarboxylic acid dialkyl ester, 2,3,4,5-tetrahydrofurantetracarboxylic acid dialkyl ester, 1,2 ,4,5-cyclohexanetetracarboxylic acid dialkyl ester, 3,4-dicarboxylic acid dialkyl ester, 3,4-dicarboxylic acid dialkyl ester, 3,4-dicarboxylic acid dialkyl ester, 3,4-dicarboxylic acid dialkyl ester, -1-Naphthalenesuccinic acid dialkyl ester, 1,2,3,4-butanetetracarboxylic acid dialkyl ester, bicyclo[3.3.0]octane-2,4,6,8-tetracarboxylic acid dialkyl ester Ester, 3,3',4,4'-dicyclohexyltetracarboxylic acid dialkyl ester, 2,3,5-tricarboxycyclopentyl acetic acid dialkyl ester, cis-3,7-dibutyl ring Oct-1,5-diene-1,2,5,6-tetracarboxylic acid dialkyl ester, tricyclo[4.2.1.0<2,5>]nonane-3,4,7,8-tetracarboxylic acid- 3,4: 7,8-dialkyl ester, hexacyclo[6.6.0.1<2,7>.0<3,6>.1<9,14>.0<10,13>]hexadecane- 4,5,11,12-Tetracarboxylic acid-4,5: 11,12-dialkyl ester, 4-(2,5-di-sideoxytetrahydrofuran-3-yl)-1,2,3,4- Tetrahydronaphthalene-1,2-dialkyl dicarboxylate, etc.

Examples of aromatic tetracarboxylic acid dialkyl esters include: pyromellitic acid dialkyl ester, 3,3',4,4'-biphenyltetracarboxylic acid dialkyl ester, 2,2',3,3'- Diphenyltetracarboxylic acid dialkyl ester, 2,3,3',4'-biphenyltetracarboxylic acid dialkyl ester, 3,3',4,4'-benzophenone tetracarboxylic acid dialkyl ester, 2 ,3,3',4'-benzophenone tetracarboxylic acid dialkyl ester, bis(3,4-dicarboxyphenyl)ether dialkyl ester, bis(3,4-dicarboxyphenyl)sulfonate Alkyl ester, dialkyl 1,2,5,6-naphthalenetetracarboxylate, dialkyl 2,3,6,7-naphthalenetetracarboxylate, etc.

When the polymer used as a composite component is polyurea, the diisocyanate used to react with the above-mentioned diamine component is not particularly limited, and can be used depending on availability, etc. The specific structure of diisocyanate is shown below. [Chemistry 57] In the formula, R ₂ and R ₃ represent an aliphatic hydrocarbon group having 1 to 10 carbon atoms.

Although aliphatic diisocyanates represented by formulas (K-1) to (K-5) have poor reactivity, they have the benefit of improving solvent solubility, such as aromatic diisocyanates represented by formulas (K-6) to (K-13). Although family diisocyanates are highly reactive and have the effect of improving heat resistance, they have the disadvantage of lowering solvent solubility. In terms of versatility and characteristics, formulas (K-1), (K-7), (K-8), (K-9), and (K-10) are more ideal. From the perspective of electrical characteristics, formula (K- 12) is more ideal. From the perspective of liquid crystal alignment, formula (K-13) is more ideal. Two or more diisocyanates can also be used in combination, and it is appropriate to apply them in various ways according to the characteristics to be obtained.

In addition, a part of the diisocyanate can also be replaced by the tetracarboxylic dianhydride described above. It can also be used in the form of a copolymer of polyamic acid and polyurea. It can also be imidized by chemical chelation, such as It is used in the form of a copolymer of polyimide and polyurea.

When the polymer used as a composite component is a polyamide, the structure of the dicarboxylic acid used for the reaction is not particularly limited. Specific examples are as follows.

Aliphatic dicarboxylic acids include: malonic acid, oxalic acid, dimethylmalonic acid, succinic acid, fumaric acid, glutaric acid, adipic acid, muconic acid, 2-methyladipic acid, trimethyl Dicarboxylic acids such as adipic acid, pimelic acid, 2,2-dimethylglutaric acid, 3,3-diethylsuccinic acid, azelaic acid, sebacic acid and suberic acid. Alicyclic dicarboxylic acids include: 1,1-cyclopropanedicarboxylic acid, 1,2-cyclopropanedicarboxylic acid, 1,1-cyclobutanedicarboxylic acid, 1,2-cyclobutanedicarboxylic acid, 1 ,3-cyclobutanedicarboxylic acid, 3,4-diphenyl-1,2-cyclobutanedicarboxylic acid, 2,4-diphenyl-1,3-cyclobutanedicarboxylic acid, 1-cyclobutene -1,2-dicarboxylic acid, 1-cyclobutene-3,4-dicarboxylic acid, 1,1-cyclopentanedicarboxylic acid, 1,2-cyclopentanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid , 1,1-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1,4-(2-norcamphene En)dicarboxylic acid, norbornene-2,3-dicarboxylic acid, bicyclo[2.2.2]octane-1,4-dicarboxylic acid, bicyclo[2.2.2]octane-2,3-dicarboxylic acid, 2, 5-Dipoxy-1,4-bicyclo[2.2.2]octanedicarboxylic acid, 1,3-adamantanedicarboxylic acid, 4,8-Dipoxy-1,3-adamantanedicarboxylic acid, 2 ,6-spiro[3.3]heptanedicarboxylic acid, 1,3-adamantanedicarboxylic acid, camphoric acid, etc. Examples of aromatic dicarboxylic acids include: phthalic acid, isophthalic acid, terephthalic acid, 5-methylisophthalic acid, 5-tertiary butylisophthalic acid, and 5-aminoisophthalic acid. Formic acid, 5-hydroxyisophthalic acid, 2,5-dimethylterephthalic acid, tetramethylterephthalic acid, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6- Naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-anthracenedicarboxylic acid, 1,4-anthraquinonedicarboxylic acid, 2,5-biphenyldicarboxylic acid, 4,4'-biphenyldicarboxylic acid, 1, 5-Diphenyldicarboxylic acid, 4,4"-terphenyldicarboxylic acid, 4,4'-diphenylmethanedicarboxylic acid, 4,4'-diphenylethanedicarboxylic acid, 4,4'-di Phenylpropanedicarboxylic acid, 4,4'-diphenylhexafluoropropanedicarboxylic acid, 4,4'-diphenyl etherdicarboxylic acid, 4,4'-bibenzyldicarboxylic acid, 4,4'-diphenyl Ethylenedicarboxylic acid, 4,4'-diphenylacetylenedicarboxylic acid, 4,4'-carbonyldibenzoic acid, 4,4'-sulfonyldibenzoic acid, 4,4'-dithiodibenzoic acid, p- Phthalated acetic acid, 3,3'-terephthalic acid, 4-carboxycinnamic acid, terephthalic acid, 3,3'-[4,4'-(methylene diphenyl)]dipropionic acid , 4,4'-[4,4'-(oxydiphenyl)]dipropionic acid, 4,4'-[4,4'-(oxydiphenyl)]dibutyric acid, ( Dicarboxylic acids such as isopropyl di-p-phenyldioxy)dibutyric acid and bis(p-carboxyphenyl)dimethylsilane. Examples of heterocyclic dicarboxylic acids include: 1,5-(9-side oxyfluoride)dicarboxylic acid, 3,4-furandicarboxylic acid, 4,5-thiazoledicarboxylic acid, 2-phenyl-4,5- Thiazoledicarboxylic acid, 1,2,5-thiadiazole-3,4-dicarboxylic acid, 1,2,5-thiadiazole-3,4-dicarboxylic acid, 2,3-pyridinedicarboxylic acid, 2,4- Picolinedicarboxylic acid, 2,5-pyridinedicarboxylic acid, 2,6-pyridinedicarboxylic acid, 3,4-pyridinedicarboxylic acid, 3,5-pyridinedicarboxylic acid, etc.

The various dicarboxylic acids mentioned above may also have a structure of acyl dihalide or anhydride. These dicarboxylic acids, especially the dicarboxylic acids that can provide polyamides with linear structures, are ideal in maintaining the alignment of liquid crystal molecules. Among them, terephthalic acid, isoterephthalic acid, 1,4-cyclohexanedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, and 4,4'-diphenylmethanedicarboxylic acid can be preferably used , 4,4'-diphenylethanedicarboxylic acid, 4,4'-diphenylpropanedicarboxylic acid, 4,4'-diphenylhexafluoropropanedicarboxylic acid, 2,2-bis(phenyl)propane Dicarboxylic acid, 4,4"-terphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,5-pyridinedicarboxylic acid or their chloride dihalides, etc. These compounds also have isomers and can also contain A mixture thereof. In addition, two or more compounds may be used in combination. In addition, the dicarboxylic acids used in the present invention are not limited to the compounds exemplified above.

The diamine used as raw material (also described as "diamine component") and the system raw material are selected from tetracarboxylic dianhydride (also described as "tetracarboxylic dianhydride component"), tetracarboxylic diester, and diisocyanate When polyamic acid, polyamic acid ester, polyurea, or polyamide are obtained by reaction with dicarboxylic acid components, known synthesis methods can be used. Generally speaking, it is a method of reacting a diamine component and one or more components selected from a tetracarboxylic dianhydride component, a tetracarboxylic diester, a diisocyanate, and a dicarboxylic acid in an organic solvent.

One of the ideal forms of the polyacrylate as a composite component is a polyacrylate other than the graft copolymer of the present invention described above. For example, it is a polymer obtained by polymerizing an industrially available free radical polymerizable monomer using a general free radical generator.

Specific examples of industrially available free radical polymerizable monomers include: unsaturated carboxylic acid, acrylate compound, methacrylate compound, maleimine compound, acrylonitrile, maleic anhydride, styrene compounds and vinyl compounds, etc.

Specific examples of unsaturated carboxylic acids include acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, and the like.

Examples of acrylate compounds include methyl acrylate, ethyl acrylate, isopropyl acrylate, benzyl acrylate, naphthyl acrylate, anthracene acrylate, anthracenyl methyl acrylate, phenyl acrylate, and 2,2,2-triacrylate. Fluoroethyl ester, tertiary butyl acrylate, cyclohexyl acrylate, isocamphenyl acrylate, 2-methoxyethyl acrylate, methoxytriethylene glycol acrylate, 2-ethoxyethyl acrylate, Tetrahydrofurfuryl acrylate, 3-methoxybutyl acrylate, 2-methyl-2-adamantyl acrylate, 2-propyl-2-adamantyl acrylate, 8-methyl-8 acrylate -Tricyclodecyl ester, and 8-ethyl-8-tricyclodecyl acrylate, etc. Glycidyl acrylate, (3-methyl-3-oxetanyl) methyl acrylate, and (3-ethyl-3-oxetanyl) methyl acrylate can also be used. Ether-like acrylate compound.

Examples of the methacrylate compound include methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, benzyl methacrylate, naphthyl methacrylate, anthracene methacrylate, and anthracene methacrylate. Methyl methacrylate, phenyl methacrylate, 2,2,2-trifluoroethyl methacrylate, tertiary butyl methacrylate, cyclohexyl methacrylate, isocamphenyl methacrylate, methacrylic acid -2-Methoxyethyl ester, methoxytriethylene glycol methacrylate, 2-ethoxyethyl methacrylate, tetrahydrofurfuryl methacrylate, 3-methoxy methacrylate Butyl ester, 2-methyl-2-adamantyl methacrylate, 2-propyl-2-adamantyl methacrylate, 8-methyl-8-tricyclodecyl methacrylate, and 8-ethyl-8-tricyclodecyl methacrylate, etc. Glycidyl methacrylate, (3-methyl-3-oxetanyl) methyl methacrylate, and (3-ethyl-3-oxetanyl) methacrylate can also be used ) methacrylate compounds with cyclic ether groups such as methyl ester.

Examples of vinyl compounds include vinyl ether, methyl vinyl ether, benzyl vinyl ether, 2-hydroxyethyl vinyl ether, phenyl vinyl ether, propyl vinyl ether, and the like.

Examples of the styrene compound include styrene, methylstyrene, chlorostyrene, bromostyrene, and the like.

Examples of the maleimide compound include maleimide, N-methylmaleimide, N-phenylmaleimide, and N-cyclohexylmaleimide.

In addition to the above-mentioned industrially available radical polymerizable monomers, side chain polymers using monomers having a liquid crystalline side chain structure (hereinafter referred to as liquid crystalline side chain monomers) may also be used. Or photosensitive monomers with photosensitive groups (hereinafter referred to as photoreactive side chain monomers), etc.

Liquid crystalline side chain monomer refers to a monomer in which the polymer derived from the monomer exhibits liquid crystallinity and the polymer can form a mesogen group at the side chain site. More specific examples of the liquid crystalline side chain monomer are preferably those selected from the group consisting of hydrocarbons, (meth)acrylate, itaconate, fumarate, maleate, and α-methylene-γ-butylene. A polymerizable group composed of at least one of the group consisting of radically polymerizable groups such as ester, styrene, vinyl, maleimide, norbornene, and a liquid crystalline side chain having The structure of at least one side chain of "liquid crystal base".

The liquid crystalline side chain monomer is preferably a monomer in which a liquid crystalline side chain selected from the following formulas (LS-1) to (LS-12) is bonded to a radically polymerizable polymerizable group. Examples of radically polymerizable polymerizable groups include polymerizable groups having a polymerizable unsaturated hydrocarbon group as exemplified in the description of the graft copolymer in the present invention. [Chemical 58] [Chemistry 59] In the formulas (LS-1) to (LS-12), A ¹ and A ² independently represent a single bond, -O-, -CH ₂ -, -C(=O)-O-, -OC(=O )-, -C(=O)NH-, -NHC(=O)-, -CH=CH-C(=O)O-, or -OC(=O)-CH=CH-, R ¹¹ means - NO ₂ , -CN, halogen atom, phenyl group, naphthyl group, biphenyl group, furyl group, monovalent nitrogen-containing heterocyclic group, monovalent alicyclic hydrocarbon group having 5 to 8 carbon atoms, and monovalent alicyclic hydrocarbon group having 1 to 12 carbon atoms. Alkyl group, or alkoxy group having 1 to 12 carbon atoms, R ¹² represents a group selected from phenyl, naphthyl, biphenyl, furyl, monovalent nitrogen-containing heterocyclic group, and monovalent lipid having 5 to 8 carbon atoms. As a group in the group consisting of cyclic hydrocarbon groups and groups obtained by combining them, among R ¹¹ and R ¹² , the hydrogen atoms bonded to them may also be -NO ₂ , -CN, halogen atoms, carbon atoms from 1 to 5 alkyl group, or alkoxy group with 1 to 5 carbon atoms substituted, R ¹³ represents a hydrogen atom, -NO ₂ , -CN, -CH=C(CN) ₂ , -CH=CH-CN, halogen atom, benzene group, naphthyl, biphenyl, furyl, monovalent nitrogen-containing heterocyclic group, monovalent alicyclic hydrocarbon group with 5 to 8 carbon atoms, alkyl group with 1 to 12 carbon atoms, or alkyl group with 1 to 12 carbon atoms. Alkoxy group, E represents -C(=O)O- or -OC(=O)-, d represents an integer from 1 to 12, k1 to k5 are independently an integer from 0 to 2, but in each formula The total of k1～k5 is more than 2, k6 and k7 are each independently an integer from 0 to 2, but in each formula the total of k6 and k7 is more than 1, m1, m2 and m3 are each independently an integer from 1 to 3, n is 0 or 1, and Z ¹ and Z ² independently represent a single bond, -C(=O)-, -CH ₂ O-, -CH=N- or -CF ₂ -. Dashed lines represent atomic bonds.

In the photoreactive side chain monomer, the photosensitive side chain is bonded to the main chain, and the photoreactive side chain monomer system has the ability to sense light and initiate cross-linking reactions, isomerization reactions, or photoreactive reactions. Rearranged side chain monomer. The structure of the photosensitive side chain is not particularly limited. It is preferably a structure that can sense light and trigger a cross-linking reaction or a photo-Frys rearrangement, and is more preferably a structure that triggers a cross-linking reaction. In this case, the achieved alignment control capability can be maintained stably for a long time even if exposed to external pressure such as heat. The structure of the photosensitive side chain type acrylic polymer film that can exhibit liquid crystallinity is not particularly limited as long as it meets such characteristics. It is preferable to have a rigid mesogen component in the side chain structure.

The structure of the acrylic polymer may be, for example, having a main chain and a side chain bonded thereto, and the side chain has a biphenyl group, a terphenyl group, a phenylcyclohexyl group, a phenyl benzoate group, a phenyl benzoate group, or a phenyl benzoate group. The structure of a mesogen component such as azophenyl group, and a photosensitive group bonded to the front end that can respond to light and perform a cross-linking reaction or isomerization reaction; or has a main chain and side chains bonded to it, and the The side chain also becomes a mesogen component and has a structure of phenyl benzoate group that undergoes photo-Fries rearrangement reaction.

A more specific example of the structure of the photosensitive side chain acrylic polymer that can exhibit liquid crystallinity within a predetermined temperature range is preferably one having a structure selected from the group consisting of hydrocarbons, (meth)acrylate, itaconate, and fumaric acid. At least one kind from the group consisting of radical polymerizable groups such as ester, maleate, α-methylene-γ-butyrolactone, styrene, vinyl, maleimide, norbornene, etc. The structure of the main chain and the side chain composed of at least one of the following formulas (31) to (35). [Chemical 60] In the formula, Ar ₁ and Ar ₂ each independently represent a divalent organic group obtained by removing two hydrogen atoms from a benzene ring, naphthalene ring, pyrrole ring, furan ring, thiophene ring, or pyridine ring, and q1 and q2 are one of them. is 1 and the other is 0, Y ₁ -Y ₂ represents CH=CH, CH=N, N=CH or CC (but the bond between carbon and carbon is a parametric bond), S ₁ and S ₂ are independent means a single bond, a linear or branched alkylene group with 1 to 18 carbon atoms, a cycloalkylene group with 5 to 8 carbon atoms, a phenyl group or a biphenyl group, or a single bond or an ether bond. , ester bond, amide bond, urea bond, urethane bond, -NR- (R represents a hydrogen atom or an alkyl group with 1 to 18 carbon atoms), and carbonyl group, or one or more of their combinations The bond, or the bond between one or more types, is selected from linear or branched alkylene groups with 1 to 18 carbon atoms, cycloalkylene groups with 5 to 8 carbon atoms, A structure in which 2 to 10 sites of a phenylene group, a biphenylene group or a combination thereof are bonded, and it may also be a structure in which the aforementioned Ar ₁ and Ar ₂ are connected by a plurality of the aforementioned bonds, respectively. Structure, R represents a hydrogen atom, a hydroxyl group, a mercapto group, an amine group, an alkyl group with 1 to 10 carbon atoms, an alkoxy group with 1 to 10 carbon atoms, an alkylamine group with 1 to 8 carbon atoms, or an alkylamine group with 2 to 16 carbon atoms. The dialkylamino group, Ar ₁ , Ar ₂ , the benzene ring and/or naphthalene ring in S ₁ and S ₂ can also be selected from the group consisting of halogen atoms, cyano groups, nitro groups, carboxyl groups and alkoxy groups with 2 to 11 carbon atoms. The carbonyl group is substituted with one or more identical or different substituents. In this case, the alkyl group having 1 to 10 carbon atoms in the alkoxycarbonyl group having 2 to 11 carbon atoms may be linear, branched, or cyclic, or may be a combination of these structures. The hydrogen atoms in the alkyl group having 1 to 10 carbon atoms may also be replaced by halogen atoms.

The manufacturing method of the aforementioned polyacrylate is not particularly limited, and a general method accepted in the industry can be used. Specifically, it can be produced by cationic polymerization, radical polymerization, or anionic polymerization of vinyl groups using liquid crystalline side chain monomers and photoreactive side chain monomers. Among them, radical polymerization is particularly preferable from the viewpoint of ease of reaction control.

As the polymerization initiator for radical polymerization, known radical polymerization initiators such as AIBN (azobisisobutyronitrile) or known compounds such as reversible addition-fragmentation chain transfer (RAFT) polymerization reagents can be used.

The radical polymerization method is not particularly limited, and emulsion polymerization, suspension polymerization, dispersion polymerization, precipitation polymerization, block polymerization, solution polymerization, etc. can be used.

The organic solvent used in the polymerization reaction of the photosensitive side-chain acrylic polymer that can exhibit liquid crystallinity within a predetermined temperature range is not particularly limited as long as it dissolves the resulting polymer. Specific examples are listed below. Examples include: N,N-dimethylformamide, N,N-diethylformamide, N,N-dibutylformamide, N,N-dimethylacetamide, N,N-dimethylformamide Ethyl acetamide, N,N-dipropylacetamide, N,N-dimethylpropionamide, N,N-diethylpropionamide, 3-methoxy-N,N-di Methylpropanamide, N-methylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N-methyl-ε-caprolactam, N,N-diethyl acetamide, N,N-dipropylacetamide, 3-methoxy-N,N-dimethylpropanamide , N,N-diethylpropamide, diethylformamide, dimethyltrisoxide, tetramethylurea, pyridine, dimethyltrisone, hexamethylphosphoramide, γ-butyrolactone, Isopropyl alcohol, methoxymethylpentyl alcohol, dipentene, ethyl amyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isopentyl ketone, methyl isopropyl ketone, methyl Cellulucet, ethylcelluteacetate, methylcelluteacetate, butylcelluteacetate, ethylcelluteacetate, diethylene glycol monobutyl ether, ethyl diethylene glycol Alcohol monoethyl ether, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether (butyl cellulose), propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether , propylene glycol monobutyl ether, propylene glycol tertiary butyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethyl Glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl- 3-Methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyrate Ester, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, 1,4-dihexane, n-hexane, n-pentane, n-octane, cyclohexane, 2-ethane Base-1-hexanol, benzene, xylene, toluene, ethylbenzene, cumene, tertiary butylbenzene, tetrahydrofuran, diethyl ether, cyclohexanone, ethyl carbonate, propyl carbonate, methyl lactate, lactic acid Ethyl ester, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl acetate, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate , 3-ethoxypropionic acid methyl ester, 3-ethoxypropionic acid ethyl ester, 3-ethoxypropionic acid, 3-methoxypropionic acid, 3-methoxypropionic acid propyl ester, 3-methyl Butyl oxypropionate, diglyme, 4-hydroxy-4-methyl-2-pentanone, 3-ethoxy-N,N-dimethylpropanamide, 3-butoxy -N,N-dimethylpropanamide, propyl pyruvate, butyl pyruvate, amyl pyruvate, hexyl pyruvate, 2-ethylhexyl pyruvate, methyl acetyl acetate, ethanol Ethyl acetate, propyl acetate, butyl acetate, amyl acetate, hexyl acetate, 2-ethylhexyl acetate, methyl acetate, propyl acetate Ethyl acetate, propyl acetyl propionate, butyl acetate propionate, amyl acetyl propionate, hexyl acetyl propionate, 2-ethylhexyl acetyl propionate, dimethyl malonate , dimethyl succinate, dimethyl glutarate, dimethyl adipate, dimethyl phthalate, dimethyl maleate, diethyl malonate, diethyl succinate, glutamate Diethyl acid, diethyl adipate, diethyl phthalate, diethyl maleate, dipropyl malonate, dipropyl succinate, dipropyl glutarate, dipropyl adipate Propyl ester, dipropyl phthalate, dipropyl maleate, dibutyl malonate, dibutyl succinate, dibutyl glutarate, dibutyl adipate, dibutyl phthalate , Dibutyl maleate, Dipentyl malonate, Dipentyl succinate, Dipentyl glutarate, Dipentyl adipate, Dipentyl phthalate, Dipentyl maleate, Propylene glycol Dihexyl diacetate, dihexyl succinate, dihexyl glutarate, dihexyl adipate, dihexyl phthalate, dihexyl maleate, di-2-ethylhexyl malonate Ester, 2-ethylhexyl succinate, 2-ethylhexyl glutarate, 2-ethylhexyl adipate, 2-ethylhexyl phthalate, maleic acid-2 -Ethylhexyl ester, etc. These organic solvents may be used alone or in mixture. In addition, even if it is a solvent that cannot dissolve the generated polymer, it can still be mixed with the above-mentioned organic solvent and used as long as the generated polymer does not precipitate. In addition, in radical polymerization, oxygen in the organic solvent may hinder the polymerization reaction, so it is preferable to use an organic solvent that is degassed as much as possible.

The polymerization temperature during free radical polymerization can be selected from any temperature ranging from 30 to 150°C, and is preferably 50 to 100°C. In addition, the reaction can be carried out at any concentration. If the concentration is too low, it will be difficult to obtain a high molecular weight polymer. If the concentration is too high, the viscosity of the reaction solution will become too high and it will be difficult to stir evenly. Therefore, the monomer concentration is preferably 1 to 50 mass%, more preferably 5 to 30 mass%. It can also be carried out at a high concentration in the initial stage of the reaction, and then the organic solvent can be added. In the above-mentioned free radical polymerization reaction, if the ratio of the free radical polymerization initiator to the monomer is larger, the molecular weight of the polymer obtained will become smaller. If it is smaller, the molecular weight of the polymer obtained will become larger, so the free radical The ratio of the initiator to the monomer to be polymerized is preferably 0.1 to 10 mol%. In addition, various monomer components, solvents, initiators, etc. may be added during polymerization.

When recovering the polymer produced by the reaction solution of the photosensitive side chain type polymer capable of exhibiting liquid crystallinity obtained by the above reaction, the reaction solution may be put into a poor solvent and these polymers may be precipitated. Examples of poor solvents used for precipitation include: methanol, acetone, hexane, heptane, butylcellulose, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, diethyl ether, methyl ethyl ether, water etc. The polymer precipitated by being put into a poor solvent can be filtered and recovered, and then dried under normal pressure or reduced pressure, at normal temperature or by heating. In addition, if the polymer obtained by precipitation and recovery is redissolved in an organic solvent, and the operation of reprecipitation and recovery is repeated 2 to 10 times, the impurities in the polymer can be reduced. Examples of poor solvents in this case include alcohols, ketones, hydrocarbons, etc. It is preferable to use three or more types of poor solvents selected from these because the purification efficiency will be further improved.

The molecular weight of the photosensitive side-chain acrylic polymer that can exhibit liquid crystallinity within a predetermined temperature range is determined by the GPC method when considering the strength of the resulting coating film, workability during coating film formation, and uniformity of the coating film. The measured weight average molecular weight is preferably 2,000 to 1,000,000, more preferably 5,000 to 100,000.

Examples of organic solvents used in liquid crystal alignment agents include: N,N-dimethylformamide, N,N-dimethylacetamide, N-methylformamide, and N-methyl-2-pyrrolidone. , N-ethyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N-methylcaprolactam, N,N-diethyl acetamide, N, N-dipropylacetamide, 3-methoxy-N,N-dimethylpropanamide, N,N-diethylpropanamide, diethylformamide, dimethylsulfoxide, Tetramethylurea, pyridine, dimethylpropane, hexamethylphosphatide, γ-butyrolactone, isopropyl alcohol, methoxymethylpentanol, dipentene, ethylamylketone, methylnonane Ketone, methyl ethyl ketone, methyl isopentyl ketone, methyl isopropyl ketone, methylcellulsuate, ethylcellulsuate, methylcellulsuate acetate, butylcellulsuate ethyl Acid ester, ethyl cellulose acetate, diethylene glycol monobutyl ether, ethyl diethylene glycol monoethyl ether, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol Glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol tertiary butyl ether, propylene glycol monomethyl ether acetate, diethylene glycol, diethylene glycol monoacetate Ester, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol mono Propyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether Ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, dihexane, n-hexane, n- Pentane, n-octane, diethyl ether, cyclohexanone, ethyl carbonate, propyl carbonate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol acetate monoethyl ether, Methyl 3-methoxypropionate, methylethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, 3- Propyl methoxypropionate, 3-butyl methoxypropionate, diethylene glycol dimethyl ether, 4-hydroxy-4-methyl-2-pentanone, 1-methoxy-2-propanol , 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanol, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2- Acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2-(2-ethoxypropoxy)propanol, 2-ethyl-1,3-hexanediol, ethyl Diol, propylene glycol (1,2-propanediol), 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 2,3-butanediol, 1 ,4-butanediol, 1,2-pentanediol, 1,3-pentanediol, 1,4-pentanediol, 1,5-pentanediol, 2-methyl-2 ,4-pentanediol, 1,2-hexanediol, 1,3-hexanediol, 1,4-hexanediol, 1,5-hexanediol, 1,6-hexane Diol, 2,3-hexanediol, 2,4-hexanediol, 2,5-hexanediol, 3,5-hexanediol, 1,2-heptanediol, 1, 3-heptanediol, 1,4-heptanediol, 1,5-heptanediol, 1,6-heptanediol, 1,7-heptanediol, 1,2-octanediol Alcohol, 1,4-octanediol, 1,8-octanediol, 1,2-nonanediol, 1,3-nonanediol, 1,5-nonanediol, 1,6 -Nonanediol, 1,9-nonanediol, 1,2-decanediol, 1,5-decanediol, 1,8-decanediol, 1,10-decanediol, 1,2 -Cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, diethylene glycol, dipropylene glycol, dibutylene glycol, glycerin, 2-ethyl-1-hexane Alcohol, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, amyl pyruvate, hexyl pyruvate, 2-ethylhexyl pyruvate, acetyl methyl acetate, acetyl Ethyl acetate, propyl acetate, butyl acetate, amyl acetate, hexyl acetate, 2-ethylhexyl acetate, methyl acetylpropionate, acetylpropionic acid Ethyl ester, propyl acetyl propionate, butyl acetyl propionate, amyl acetyl propionate, hexyl acetyl propionate, 2-ethylhexyl acetyl propionate, dimethyl malonate, Dimethyl succinate, dimethyl glutarate, dimethyl adipate, dimethyl phthalate, dimethyl maleate, diethyl malonate, diethyl succinate, glutaric acid Diethyl ester, diethyl adipate, diethyl phthalate, diethyl maleate, dipropyl malonate, dipropyl succinate, dipropyl glutarate, dipropyl adipate Ester, dipropyl phthalate, dipropyl maleate, dibutyl malonate, dibutyl succinate, dibutyl glutarate, dibutyl adipate, dibutyl phthalate, Dibutyl maleate, dipyl malonate, dipyl succinate, dipyl glutarate, dipyl adipate, dipyl phthalate, dipyl maleate, propylene glycol Dihexyl acid, dihexyl succinate, dihexyl glutarate, dihexyl adipate, dihexyl phthalate, dihexyl maleate, di-2-ethylhexyl malonate , 2-ethylhexyl succinate, 2-ethylhexyl glutarate, 2-ethylhexyl adipate, 2-ethylhexyl phthalate, 2-maleic acid Ethylhexyl ester, etc. These organic solvents can be used individually or in mixture.

It is also preferable to mix a solvent that improves the uniformity and smoothness of the coating film with a highly soluble organic solvent.

Solvents that improve the uniformity and smoothness of the coating film include, for example, isopropyl alcohol, methoxymethylpentanol, methylcellulose, ethylcellulose, methylcellulose acetate, butyl Ethyl diethylene glycol monoethyl ether, ethyl diethylene glycol monobutyl ether, ethyl diethylene glycol monoethyl ether acetate, ethyl diethylene glycol monoethyl ether acetate, Ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether (butyl cellulose), propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol triacetate Grade butyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, propylene glycol Monomethyl ether acetate, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl ethyl Acid ester, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl Ketone, methylcyclohexene, propyl ether, dihexyl ether, n-hexane, n-pentane, n-octane, diethyl ether, methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, isolactic acid Amyl ester, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl acetate, methyl 3-methoxypropionate, methylethyl 3-ethoxypropionate, 3-methoxypropionic acid Ethyl ester, 3-ethoxypropionic acid, 3-methoxypropionic acid, 3-methoxypropionic acid propyl ester, 3-methoxypropionic acid butyl ester, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanol, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-ethyl Acid ester, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2-(2-ethoxypropoxy)propanol, 2-ethyl-1-hexanol, methyl pyruvate, acetone Ethyl pyruvate, propyl pyruvate, butyl pyruvate, amyl pyruvate, hexyl pyruvate, 2-ethylhexyl pyruvate, methyl acetate, ethyl acetate, propyl acetate Ester, butyl acetyl acetate, amyl acetyl acetate, hexyl acetyl acetate, 2-ethylhexyl acetyl acetate, methyl acetyl propionate, ethyl acetyl propionate, propyl acetyl propionate Ester, butyl acetyl propionate, amyl acetyl propionate, hexyl acetyl propionate, 2-ethylhexyl acetyl propionate, dimethyl malonate, dimethyl succinate, pentylene glycol Dimethyl acid, dimethyl adipate, dimethyl phthalate, dimethyl maleate, diethyl malonate, diethyl succinate, diethyl glutarate, diethyl adipate Ethyl ester, diethyl phthalate, diethyl maleate, dipropyl malonate, dipropyl succinate, dipropyl glutarate, dipropyl adipate, dipropyl phthalate , dipropyl maleate, dibutyl malonate, dibutyl succinate, dibutyl glutarate, dibutyl adipate, dibutyl phthalate, dibutyl maleate, propyl Dipentyl diphosphate, dipyl succinate, dipyl glutarate, dipyl adipate, dipyl phthalate, dipyl maleate, dihexyl malonate, dipentyl succinate Hexyl ester, dihexyl glutarate, dihexyl adipate, dihexyl phthalate, dihexyl maleate, di-2-ethylhexyl malonate, 2-ethyl succinate Hexyl ester, 2-ethylhexyl glutarate, 2-ethylhexyl adipate, 2-ethylhexyl phthalate, 2-ethylhexyl maleate, etc. Various types of these solvents can also be mixed. When these solvents are used, it is suitable to account for 5 to 80 mass % of the total solvent contained in the liquid crystal alignment agent, and more preferably 20 to 60 mass %.

The weakly anchored liquid crystal alignment agent of the present invention may also contain components other than those mentioned above. Examples include: compounds that improve the film thickness uniformity and surface smoothness of the composition contained in the weakly anchored liquid crystal alignment agent during coating; compounds that improve the density between the composition contained in the weakly anchored liquid crystal alignment agent and the substrate; Compounds that improve the compatibility, compounds that further improve the film strength of the composition contained in the weakly anchored liquid crystal alignment agent, etc.

Examples of compounds that improve film thickness uniformity and surface smoothness include fluorine-based surfactants, polysiloxane-based surfactants, and nonionic surfactants. More specifically, examples include: F-top EF301, EF303, EF352 (manufactured by Mitsubishi Materials Electronics Corporation), MEGAFACE F171, F173, R-30 (manufactured by DIC Corporation), FLUORAD FC430, FC431 (manufactured by 3M Corporation) , AsahiGuard AG710 (manufactured by AGC Corporation), SURFLON S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by AGC SEIMI CHEMICAL Corporation), etc. When these surfactants are used, the usage ratio is preferably 0.01 to 2 parts by mass, and preferably 0.01 to 1 part by mass relative to 100 parts by mass of the total polymer contained in the composition of the weakly anchored liquid crystal alignment agent. good.

Specific examples of compounds that improve the adhesion between the composition of the weakly anchored liquid crystal alignment agent and the substrate include functional silane-containing compounds, epoxy group-containing compounds, and the like. Examples include: 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-urea Propyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyl Triethoxysilane, N-(3-triethoxysilyl)propyltriethylenetetramine, N-(3-trimethoxysilyl)propyltriethylenetetramine, 10-trimethoxy Silyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, acetic acid-9-trimethoxysilyl-3,6 -Diazenonyl ester, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3 -Aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, ethylene glycol diepoxy Propyl ether, polyethylene glycol diepoxypropyl ether, propylene glycol diepoxypropyl ether, tripropylene glycol diepoxypropyl ether, polypropylene glycol diepoxypropyl ether, neopentyl glycol diepoxypropyl ether, 1,6- Hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraepoxypropyl-2,4 -Hexanediol, N,N,N',N'-tetraepoxypropylm-xylylenediamine, 1,3-bis(N,N-diepoxypropylaminomethyl)cyclohexane , N,N,N',N'-tetraepoxypropyl-4,4'-diaminodiphenylmethane, 3-(N-allyl-N-epoxypropyl)aminopropyl Trimethoxysilane, 3-(N,N-diepoxypropyl)aminopropyltrimethoxysilane, etc.

In addition, in order to further improve the film strength of the weakly anchored liquid crystal alignment film, 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl)propane or tetrakis(methoxymethyl)bis may also be added. Phenolic compounds such as phenol. When these compounds are used, the amount is preferably 0.1 to 30 parts by mass, and more preferably 1 to 20 parts by mass relative to 100 parts by mass of the total polymer contained in the weakly anchored liquid crystal alignment agent. In addition, in the composition of the weakly anchored liquid crystal alignment agent, in addition to adding the above, within the scope that does not impair the effect of the present invention, the dielectric constant used to increase the weakly anchored liquid crystal alignment film can also be added. , dielectrics and conductive substances whose electrical properties such as conductivity change.

(Strongly anchored horizontal alignment film) A strong anchoring horizontal alignment film must be provided on the substrate on the opposite side of the substrate with a weakly anchored liquid crystal alignment film. The so-called strongly anchored horizontal alignment film here refers to a liquid crystal alignment film that can evenly align liquid crystals in the horizontal direction and has a strong enough interface anchoring energy to maintain the aligned liquid crystals.

Strong anchoring of the horizontal alignment film can be achieved by using the above-described polyamide or polyimide, polyamide ester, polyamide, polyester, polyacrylate, etc., through friction directional alignment treatment or photo alignment treatment. It is obtained by performing alignment processing along the uniaxial direction.

Strongly anchored horizontal alignment films can be obtained using a combination of the aforementioned monomers.

(Weakly anchored liquid crystal alignment film and strongly anchored horizontal alignment film) The weakly anchored alignment film of the present invention can be obtained by using the above weakly anchored liquid crystal alignment agent. For example, the cured film obtained by applying the weakly anchored liquid crystal alignment agent used in the present invention to a substrate, drying, and calcining can be directly used as a weakly anchored liquid crystal alignment film. In addition, the cured film may be subjected to alignment treatment by rubbing, irradiation with polarized light, light of a specific wavelength, or ion beam, or UV irradiation of the liquid crystal display element filled with liquid crystal.

A strong anchoring horizontal alignment film can also be obtained by subjecting a cured film obtained by applying a strong anchoring liquid crystal alignment agent to a substrate, drying, and calcining the cured film through alignment treatment.

In the present invention, the first substrate may be a substrate having comb-shaped electrodes, and the second substrate may be a counter substrate. Furthermore, in the present invention, the second substrate may be a substrate having comb-shaped electrodes, and the first substrate may be a counter substrate.

The substrate on which each liquid crystal alignment film is coated is not particularly limited or is a substrate with high transparency. It is preferably a substrate on which a transparent electrode for driving liquid crystal has been formed.

Specific examples include glass plates, polycarbonates, poly(meth)acrylates, polyether esters, polyarylates, polyurethanes, polyesters, polyethers, polyetherketones, trisulfones, etc. Plastic plates such as methylpentene, polyolefin, polyethylene terephthalate, (meth)acrylonitrile, triacetyl cellulose, diethyl cellulose, cellulose acetate butyrate, etc. form transparent electrodes of substrate.

It can be used as a substrate for IPS liquid crystal display elements, and can also use electrode patterns such as standard IPS comb electrodes, PSA (Polymer-Stabilized Alignment) fishbone electrodes, and protrusion patterns such as MVA (Multi-domain Vertical Alignment).

In addition, in highly functional devices such as TFT (Thin-Film-Transistor) type devices, devices such as transistors formed between electrodes for driving liquid crystals and a substrate are used.

When a transmissive liquid crystal display element is desired, the above-mentioned substrate is generally used. When a reflective liquid crystal display element is desired, if only a single-sided substrate is used, an opaque substrate such as a silicon wafer can also be used. At this time, the electrode formed on the substrate may also be made of a material that reflects light, such as aluminum.

Coating methods for weakly anchored liquid crystal alignment agents include: spin coating, printing, inkjet, spray, roller coating, etc. In terms of productivity, the transfer printing method is widely used in industry. Also ideal for use.

The drying step after coating the liquid crystal alignment agent is not necessary. However, when the time from coating to before calcination is not fixed for each substrate, or when calcination is not performed directly after coating, a drying step should be included. This drying only needs to remove the solvent to an extent that the shape of the coating film will not be deformed due to transportation of the substrate, etc., and the drying method is not particularly limited. The ideal conditions for the drying step can be listed as drying on a hot plate at a temperature of 40 to 150°C, preferably 60 to 100°C for 0.5 to 30 minutes, and more preferably 1 to 5 minutes. The ideal conditions for the calcination step can be listed as calcination at a temperature of 80 to 250°C, preferably a heating plate or a thermal circulation oven at 100 to 230°C for 1 to 120 minutes, and more preferably 5 to 30 minutes.

The thickness of the cured film can be selected according to needs. It is preferably 5 nm or more, and more preferably 10 nm or more, because it can improve the reliability of the liquid crystal display element, so it is more ideal. In addition, the thickness of the cured film is preferably 300 nm or less, more preferably 150 nm or less, because the power consumption of the liquid crystal display element does not become extremely high, which is preferable.

In the above manner, a first substrate or a second substrate having a weakly anchored liquid crystal alignment film, and a second substrate or a first substrate having a strongly anchored horizontal alignment film can be obtained. Methods for implementing uniaxial alignment processing include: photo alignment method, oblique evaporation method, friction directional alignment method, uniaxial alignment processing using magnetic field, etc.

When performing an alignment process in which a friction alignment process is performed in a single direction, the substrate is moved in such a manner that the rubbing alignment cloth and the film are brought into contact with each other while rotating a friction alignment roller around which the friction alignment cloth is wound. When using the photo-alignment method, the film can be aligned by irradiating the entire film with polarized UV of a specific wavelength and heating as needed.

When forming a substrate with comb-shaped electrodes, the direction is selected based on the electrical properties of the liquid crystal. When using a liquid crystal with positive dielectric anisotropy, the rubbing orientation direction should be approximately the same as the extending direction of the comb-shaped electrodes. direction.

[liquid crystal cell] The liquid crystal cell of the present invention utilizes the above method by combining a substrate (such as a first substrate) with a weakly anchored liquid crystal alignment film obtained by using the liquid crystal alignment agent of the present invention, and a well-known strongly anchored liquid crystal alignment film. The substrate (for example, the second substrate) is obtained by arranging the weakly anchored liquid crystal alignment film and the strongly anchored liquid crystal alignment film facing each other, holding the spacer and fixing it with a sealant, injecting liquid crystal and sealing. At this time, the size of the spacer used is usually 1 to 30 μm, preferably 2 to 10 μm. In addition, by making the rubbing orientation direction of the first substrate parallel to the rubbing orientation direction of the second substrate, it can be used in the IPS method and the FFS method. If the rubbing orientation directions are arranged to perpendicularly intersect, it can be used in the TN method.

In addition, the IPS substrate, which is a comb-shaped electrode substrate used in the IPS method, has a base material, a plurality of linear electrodes formed on the base material and arranged in a comb-like shape, and a linear electrode formed on the base to cover the base material. Liquid crystal alignment film on the material.

In addition, the comb-tooth electrode substrate used in the FFS method, that is, the FFS substrate, has a base material, a surface electrode formed on the base material, an insulating film formed on the surface electrode, and an insulating film formed on the insulating film and arranged in a comb-tooth shape. A plurality of linear electrodes, and a liquid crystal alignment film formed on the insulating film to cover the linear electrodes.

(Liquid crystal display element) The liquid crystal display element includes, for example, a first substrate, a second substrate arranged to face the first substrate, and liquid crystal filled between the first substrate and the second substrate. Then, the liquid crystal display element uses the first substrate or the second substrate with the weakly anchored liquid crystal alignment film coated with the weakly anchored liquid crystal alignment agent of the present invention to form a film, and the second substrate with the strongly anchored horizontal alignment film. substrate or first substrate.

For example, a liquid crystal display element can be made into a reflective liquid crystal display element by arranging a reflective electrode, a transparent electrode, a λ/4 plate, a polarizing film, a color filter layer, etc. in a liquid crystal cell according to the needs according to common methods. In addition, according to the needs, a transmissive liquid crystal display element can also be made by arranging a backlight, a polarizing plate, a λ/4 plate, a transparent electrode, a polarizing film, a color filter layer, etc. in a liquid crystal cell according to common methods.

FIG. 1 is a schematic cross-sectional view showing an example of a transverse electric field liquid crystal display element of the present invention, which is an example of an IPS mode liquid crystal display element.

In the lateral electric field liquid crystal display element 1 illustrated in FIG. 1 , the liquid crystal 3 is sandwiched between the comb-shaped electrode substrate 2 provided with the liquid crystal alignment film 2 c and the counter substrate 4 provided with the liquid crystal alignment film 4 a. The comb electrode substrate 2 has a base material 2a, a plurality of linear electrodes 2b formed on the base material 2a and arranged in a comb-like shape, and a liquid crystal alignment formed on the base material 2a to cover the linear electrodes 2b. Membrane 2c. The counter substrate 4 has: a base material 4b, and a weakly anchored liquid crystal alignment film or a strongly anchored horizontal alignment film (liquid crystal alignment film 4a) formed on the base material 4b. The liquid crystal alignment film 2c is, for example, the weakly anchored liquid crystal alignment film or the strongly anchored horizontal alignment film of the present invention. The liquid crystal alignment film on the opposing substrate is made of a combination of a strong anchoring horizontal alignment film and a weak anchoring liquid crystal alignment film. In this horizontal electric field liquid crystal display element 1, when a voltage is applied to the linear electrodes 2b, an electric field is generated between the linear electrodes 2b as shown by the electric force line L.

2 is a schematic cross-sectional view showing another example of a transverse electric field liquid crystal display element of the present invention, which is an example of an FFS mode liquid crystal display element.

In the lateral electric field liquid crystal display element 1 illustrated in FIG. 2 , the liquid crystal 3 is sandwiched between the comb-shaped electrode substrate 2 provided with the liquid crystal alignment film 2 h and the counter substrate 4 provided with the liquid crystal alignment film 4 a. The comb-tooth electrode substrate 2 has a base material 2d, a surface electrode 2e formed on the base material 2d, an insulating film 2f formed on the surface electrode 2e, and a plurality of lines formed on the insulating film 2f and arranged in a comb-tooth shape. The electrode 2g and the liquid crystal alignment film 2h are formed on the insulating film 2f to cover the linear electrode 2g. The counter substrate 4 has a base material 4b and a liquid crystal alignment film 4a formed on the base material 4b. The liquid crystal alignment film 4a is the same as the liquid crystal alignment film 4a in FIG. 1 described above. The liquid crystal alignment film 2h is the same as the liquid crystal alignment film 2c in FIG. 1 described above. In this horizontal electric field liquid crystal display element 1, when a voltage is applied to the surface electrode 2e and the linear electrode 2g, an electric field is generated between the surface electrode 2e and the linear electrode 2g as shown by the electric force line L. [Example]

The following examples are given to illustrate the present invention in detail, but the present invention is not to be construed as being limited to these examples. The abbreviations of the compounds and the measurement methods of each characteristic are as follows.

(Radically polymerizable monomer compatible with liquid crystal) [Chemical 61]

(Radically polymerizable monomer insoluble in liquid crystal) [Chemical 62] Me represents methyl.

(RAFT agent) [Chemical 63]

(RAFT removal agent) [Chemical 64]

(Chain transfer agent) [Chemical 65]

(Thermal polymerization initiator) [Chemical 66]

(Diamine) [Chemical 67] Boc represents tertiary butoxycarbonyl.

(Tetracarboxylic dianhydride) [Chemical 68]

(Additive) [Chemical 69]

(Raw materials for polymer (RSM)) ISOBAM-06: Poly(isobutylene-o-maleic anhydride) (weight average molecular weight 80,000 to 90,000, manufactured by Kuraray Corporation) ISOBAM-10: Poly(isobutylene-o-maleic anhydride) (weight average molecular weight 160,000 to 170,000, manufactured by Kuraray Corporation) ISOBAM-18: Poly(isobutylene-o-maleic anhydride) (weight average molecular weight 300,000 to 350,000, manufactured by Kuraray Corporation)

(nucleophile) [Chemical 70]

(catalyst) DMAP: 4-dimethylaminopyridine

(solvent) THF: Tetrahydrofuran NMP: N-methyl-2-pyrrolidone BCA: Ethylene glycol monobutyl ether acetate PB: propylene glycol monobutyl ether

(viscosity measurement) The viscosity of the polyamide solution, etc. is measured using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.), with a sample volume of 1.1 mL (milliliter), a conical rotor TE-1 (1°34', R24), Measurement was carried out at a temperature of 25°C.

(Measurement of molecular weight) The molecular weights of polyimide precursors and synthesized polymers other than polyimide were measured using a room temperature gel permeation chromatography (GPC) device (CBM-20A) (manufactured by Shimadzu Corporation) and a column (Shodex (registered) Trademark) KF-804L and KF-803L in series) (manufactured by Showa Denko Co., Ltd.) and measured as follows. Tube string temperature: 40℃ Mobile phase: tetrahydrofuran Flow rate: 1.0mL/min Standard sample for calibration line production: Standard polystyrene (molecular weight: 197,000, 55,100, 12,800, 3,950, 1,260) (manufactured by Tosoh Corporation)

The molecular weights of the polyimide precursor and the polyimide were determined using a normal temperature gel permeation chromatography (GPC) device (GPC-101) (manufactured by Showa Denko Co., Ltd.) and a column (GPC KD-803, GPC KD-805 series connection) (manufactured by Showa Denko Co., Ltd.), and measure as follows. Column temperature: 50°C Mobile phase: N,N-dimethylformamide (the additive is lithium bromide monohydrate (LiBr･H ₂ O) 30mmol/L (liter), phosphoric acid-anhydrous crystal (orthophosphoric acid) 30mmol/ L, tetrahydrofuran (THF) 10mL/L) Flow rate: 1.0mL/min Standard sample for calibration line production: TSK standard polyethylene oxide (molecular weight; approximately 900,000, 150,000, 100,000 and 30,000) (manufactured by Tosoh Corporation) and Polyethylene glycol (molecular weight; approximately 12,000, 4,000, and 1,000) (manufactured by Polymer Laboratory Co., Ltd.).

＜Synthesis of polymer (RSM)＞ (Synthesis Example 1-1) In a 100mL eggplant-shaped flask equipped with a stirrer and a nitrogen inlet tube, measure ISOBAM-06 (10.0g) and catalyst DMAP (0.100g), and add nucleophile C-1 (40.0g) and solvent NMP (40.0g) was heated and stirred in an oil bath set at 80°C for 24 hours. After heating and stirring, the nucleophile was distilled off under reduced pressure to obtain a polymer (RSM-1) (NMP solution) with a viscosity of 33.6 mPa･s.

(Synthesis Examples 1-2 to 1-5) The polymer RSM shown in Table 1 below was obtained by performing the same procedure as Synthesis Example 1-1 except that the types of raw materials and nucleophile agents used were replaced with those shown in Table 1 below. -2~RSM-5.

[Table 1]

＜Synthesis of Homopolymer＞ (Synthesis example 2-1) In a 100mL eggplant-shaped flask equipped with a stirrer and a nitrogen gas introduction tube, measure A-1 (10.0g, 58.7mmol), R-3 (421mg, 1.04mmol), and AIBN (17.1mg, 0.104mmol), and add After stirring and dissolving THF (10.4g) at room temperature, the system was replaced with nitrogen, and heated and stirred in an oil bath set to 60°C for 24 hours. After heating and stirring, methanol (60 g) was slowly poured into the reaction solution while stirring to precipitate solid, and the mixture was stirred for another 30 minutes. The precipitate was separated and extracted by filtration, and then the slurry was washed twice with methanol (60 g) for 30 minutes in total, and the solid was vacuum dried at 50° C. to obtain homopolymer mCTA-1. Number average molecular weight (Mn): 10,800, weight average molecular weight (Mw): 13,000.

(Synthesis Examples 2-2 to 2-14) Except that the type, feed amount, and polymerization concentration of the raw materials (monomers) used were replaced with those shown in Table 2 below, the same procedure as in Synthesis Example 2-1 was performed to obtain the results shown in Table 2 below. Shown as homopolymer.

[Table 2]

＜Synthesis of homopolymer using terminal group conversion＞ (Synthesis example 2-15) In a 100 mL eggplant-shaped flask equipped with a stirrer and a nitrogen gas introduction tube, mCTA-1 (5.200 g, 0.4814 mmol) obtained in Synthesis Example 2-1 was measured, THF (5.200 g) was added, and the mixture was stirred and dissolved at room temperature. The system was replaced with nitrogen, AM-1 (144.7 mg, 2.407 mmol) was added, and the mixture was stirred at room temperature for 6 hours. After confirming that the reaction solution was transparent, methanol (31 g) was slowly injected into the reaction solution while stirring to precipitate solid, and the mixture was stirred for another 30 minutes. The precipitate was separated and extracted by filtration, and then the slurry was washed twice with methanol (31 g) for 30 minutes in total, and the solid was vacuum dried at 50° C. to obtain homopolymer mTT-1. Number average molecular weight (Mn): 10,100, weight average molecular weight (Mw): 12,400.

＜Synthesis of block copolymer＞ (Synthesis example 3-1) In a 100 mL eggplant-shaped flask equipped with a stirrer and a nitrogen gas introduction tube, measure mCTA-1 (7.71g, 0.714mmol), B-2 (3.00g, 11.9mmol), and AIBN (11.7) obtained in Synthesis Example 2-1. mg, 0.0714mmol), and add THF (10.7g), stir and dissolve at room temperature, replace the system with nitrogen, and heat and stir in an oil bath set to 60°C for 24 hours. After heating and stirring, methanol (60 g) was slowly poured into the reaction solution while stirring to precipitate solid, and the mixture was stirred for another 30 minutes. The precipitate was separated and extracted by filtration, and then slurry-washed twice with methanol (60 g) for 30 minutes in total, and the solid was vacuum-dried at 50° C. to obtain block copolymer BCP-1. Number average molecular weight (Mn): 14,600, weight average molecular weight (Mw): 20,400.

(Synthesis Examples 3-2 to 3-6) Except for replacing the types and feed amounts of raw materials (polymers and monomers) used with those shown in Table 3 below, the same procedure as in Synthesis Example 3-1 was performed to obtain the results shown in Table 3 below. Shown as homopolymer.

[table 3]

＜Synthesis of polymer monomers＞ (Synthesis Example 4-1) In a 100mL eggplant-shaped flask equipped with a stirrer and a nitrogen gas introduction tube, measure A-2 (10.00g, 78.02mmol), S-4 (0.216g, 2.341mmol) and AIBN (0.128g, 0.7802mmol), and THF (10.3g) was added, stirred and dissolved at room temperature, the system was replaced with nitrogen, and heated and stirred in an oil bath set to 60° C. for 12 hours. After heating and stirring, cold methanol (30.0 g) was slowly poured into the reaction solution while stirring to precipitate solid, and the mixture was stirred for another 30 minutes. The precipitate was separated and extracted by filtration, and then the prepolymer was obtained by slurry washing twice with cold methanol (30.0 g) for 30 minutes in total, and vacuum drying the solid at 50°C. Mn: 6,000, Mw: 9,900. In a 100 mL eggplant-shaped flask equipped with a stirrer and a nitrogen introduction tube, add the prepolymer synthesized by the aforementioned method (10.00g, 1.667mmol), B-5 (0.830.829g, 5.833mmol), and hydroquinone (8.1mg) , N,N-dimethyllaurylamine (2.0 mg) and xylene (20.0 g) were stirred and dissolved at room temperature, and then heated and stirred in an oil bath set to 140°C for 6 hours. After heating and stirring, methanol (50.0 g) was slowly poured into the reaction solution while stirring to precipitate a solid, and the mixture was stirred for another 30 minutes. The precipitate was separated and extracted by filtration, and then slurry-washed twice with methanol (50.0 g) for 30 minutes in total, and the solid was vacuum-dried at 50° C. to obtain the polymer monomer (MA-1). Mn: 6,100, Mw: 9,900.

＜Synthesis of graft copolymer＞ (Synthesis Example 4-2) In a 100mL eggplant-shaped flask equipped with a stirrer and a nitrogen gas introduction tube, measure the polymer monomer MA-1 (1.00g, 0.167mmol), B-3 (4.10g, 16.5mmol), and AIBN (82.1mg, 0.500 mmol), and add THF (7.77g), stir and dissolve at room temperature, replace the system with nitrogen, and heat and stir in an oil bath set to 60°C for 12 hours. After heating and stirring, methanol (40 g) was slowly poured into the reaction solution while stirring to precipitate solid, and the mixture was stirred for another 30 minutes. The precipitate was separated and extracted by filtration, and then slurry-washed twice with methanol (40 g) for 30 minutes in total, and the solid was vacuum-dried at 50° C. to obtain a graft copolymer (GP-1). Number average molecular weight (Mn): 92,200, weight average molecular weight (Mw): 196,600.

＜Synthesis of bottle brush polymer＞ (Synthesis Example 4-3) In a 100mL eggplant-shaped flask equipped with a stirrer and a nitrogen inlet tube, measure 2-((2-bromo-2-methylpropyl)oxy)ethyl methacrylate (5.00g, 17.91mmol), B-4 (0.078g, 0.60mmol), R-3 (0.72g, 1.80mmol) and AIBN (0.09g, 0.54mmol) were added, and THF (10.2g) was added. After stirring and dissolving at room temperature, the system was Replace with nitrogen, heat and stir in an oil bath set at 60°C for 12 hours. After heating and stirring, methanol (50.0 g) was slowly poured into the reaction solution while stirring to precipitate a solid, and the mixture was stirred for another 30 minutes. The precipitate was separated and extracted by filtration, and then slurry-washed twice with methanol (50.0 g) for 30 minutes in total, and the solid was vacuum-dried at 50° C. to obtain the polymer monomer (MA-2). Mn: 45,300, Mw: 68,000. In a 50 mL eggplant-shaped flask equipped with a stirrer and a nitrogen gas introduction tube, add the polymer monomer synthesized by the aforementioned method (MA-2: 2.00g, 0.03mmol), B-3 (0.43g, 1.76mmol), and A- 1 (3.00g, 17.62mmol), ethyl 2-bromoisobutyrate (0.012g, 0.06mmol), CuBr (0.03g, 0.19mmol), N,N,N',N'',N''-five After stirring and dissolving methyldiethylenetriamine (0.043g, 0.25mmol) and methylphenyl ether (7.5g) at room temperature, perform freezing and degassing three times, and heat in an oil bath set to 90°C. Stir for 6 hours. After heating and stirring, methanol (50.0 g) was slowly poured into the reaction solution while stirring to precipitate a solid, and the mixture was stirred for another 30 minutes. The precipitate was separated and extracted by filtration, and then slurry washed twice with methanol (50.0 g) for 30 minutes in total, and the solid was vacuum dried at 50° C. to obtain bottlebrush polymer (BBP-1). Mn: 203,000, Mw: 384,000.

＜Synthesis of polyamic acid and polyimide＞ (Synthesis example 5-1) In a 100mL four-necked flask equipped with a mechanical stirrer and a nitrogen introduction tube, measure DA-1 (0.584g, 5.400mmol), DA-2 (1.978g, 8.100mmol), and DA-3 (2.595g, 8.100mmol). ) and DA-4 (1.844g, 5.400mmol), and add NMP (93.73g). After stirring and dissolving in a nitrogen environment, add TC-1 (5.629g, 25.11mmol) while keeping the temperature below 10°C in an ice bath. , reacted for 18 hours at room temperature in a nitrogen atmosphere, thereby obtaining a polyamic acid (PAA-1) solution with a viscosity of about 200 mPa･s and a solid content concentration of 12 mass%. The molecular weight of this polyamide is Mn: 12,600 and Mw: 35,200.

(Synthesis example 5-2) In a 300 mL eggplant-shaped flask equipped with a stirrer and a nitrogen introduction tube, measure the polyamide (PAA-1) solution (40.0g) obtained above, add NMP (74.3g), and stir briefly at room temperature. Then, acetic anhydride (5.61g: 55.0mmol) and pyridine (2.90g, 36.7mmol) were added, and the mixture was stirred at room temperature under a nitrogen atmosphere for 30 minutes, and then reacted at 50° C. for 3 hours under a nitrogen atmosphere. After the reaction was completed, the reaction solution was slowly poured into methanol (500 mL) cooled to below 10° C. while stirring to precipitate solid, and the mixture was stirred for another 10 minutes. The precipitate was separated and extracted by filtration, and then the slurry was washed twice with methanol (200 mL) for 30 minutes in total, and the solid was vacuum dried at 80°C to obtain the target polyimide powder (SPI-1). ) (7.04g, yield 88%). The polyimide has an imidization rate of 66%, a molecular weight of Mn: 12,200, and Mw: 36,600.

[Table 4]

＜Preparation of weakly anchored liquid crystal alignment agent＞ (Preparation Example 1) In a 30 mL vial equipped with a stirrer, 0.42 g of BCP-1 obtained in Synthesis Example 3-1 and 0.9 g of the NMP solution of RSM-1 obtained in Synthesis Example 1-1 were measured, and 4.4 g of BCA were added. , PB 3.0g, and NMP 1.28g, and stirred at room temperature for 1 hour to obtain a weakly anchored liquid crystal alignment agent (WAS-1). The mass % (wt%) of each component in the weakly anchored liquid crystal alignment agent (WAS-1) is shown in Table 5.

(Preparation Examples 2 to 29) The types of polymers and solvents used were adjusted to those shown in Table 5 below, and the mass % (wt%) of each component in the obtained weakly anchored liquid crystal alignment agent was adjusted to the mass shown in Table 5 below. % (wt%), except that the same procedure as Preparation Example 1 was carried out to obtain weakly anchored liquid crystal alignment agents (WAS-2) to (WAS-29) shown in Table 5 below.

[table 5]

In addition, RSM-1 to RSM-5 are polymers having a structural unit represented by formula (1). BCP-1 to BCP-6 are polymer A and are components showing weak anchoring properties. GP-1 is polymer B and is a component showing weak anchoring properties. mCTA-7 to mCTA-10, mTT-1, and mTr-1 to mTr-2 are polymer C, and are components showing weak anchoring properties. BBP-1 is a polymer other than polymers A, B, and C, and is a component showing weak anchoring properties. BS-1 to BS-2 are polymers different from the polymer having the structural unit represented by formula (1).

(Preparation of liquid crystal display element) The following is an example of a method of producing a liquid crystal cell for evaluating liquid crystal alignment and electro-optical response. First prepare a substrate with electrodes. The substrate uses an alkali-free glass substrate with a size of 30mm×35mm and a thickness of 0.7mm. An ITO (INDIUM-TIN-OXIDE) electrode with a comb-shaped pattern with an electrode width of 3 μm, a spacing of 6 μm between electrodes, and an angle of 10° with respect to the long side of the substrate is formed on the substrate to form pixels. The size of each pixel is 10mm vertically and approximately 5mm horizontally. Hereinafter referred to as IPS substrate. Then, the liquid crystal alignment agents (WAS-1 to WAS-29) and liquid crystal alignment agents for horizontal alignment (SE-6414, NRB-U973 (manufactured by Nissan Chemical Co., Ltd.)) obtained by the above method were filtered through filters with a pore diameter of 1.0 mm. After filtration, spin coating was performed on the prepared above-mentioned IPS substrate and a glass substrate with an ITO film and a columnar spacer with a height of 3.0 μm formed on the back side of the counter substrate (hereinafter referred to as the counter substrate). Implement coating and film formation. Then, it was dried on a hot plate at 80° C. for 2 minutes, and then calcined at 230° C. for 30 minutes to obtain a coating film with a film thickness of 100 nm. In the coating film on the IPS substrate, the alignment process is carried out in the direction of the comb tooth direction, and in the coating film on the counter substrate, the alignment process is carried out in the direction perpendicular to the comb tooth electrode. In addition, during the alignment process, the friction alignment method is used for SE-6414, the photo alignment method is used for NRB-U973, and the alignment process is not performed for WAS-1 to WAS-29, and the calcined substrate is used directly. The friction orientation method uses a friction orientation device manufactured by Iinuma-gauge Co., Ltd., a friction orientation cloth (YA-20R) manufactured by Yoshikawa Chemical Co., Ltd., a friction orientation roller (roller diameter 10.0cm), a pedestal feed speed of 30mm/s, a roller rotation speed of 700rpm, and push pressure. Pressure 0.3mm to implement. The photo-alignment method uses a UV exposure device manufactured by USHIO to irradiate linearly polarized UV with an extinction ratio of approximately 26:1 using a wavelength of 254nm as a reference to achieve an exposure dose of 300mJ/ ^cm2 , and then heat it at 230°C. 30 minutes to implement the alignment process. Thereafter, the above two types of substrates were used and combined as shown in Table 6 and Table 7 below, so that the respective alignment directions became parallel, leaving the liquid crystal injection port and sealing the surrounding area (sealing agent: XN-1500T (manufactured by Mitsui Chemicals Co., Ltd.), heat treatment was performed at 150° C. for 60 minutes to harden the sealant, and an empty unit cell with a unit cell gap of approximately 3.0 μm was obtained. After injecting liquid crystal (MLC-3019 (manufactured by Merck)) into the empty cell under normal temperature vacuum, the injection port was sealed to form an anti-parallel alignment liquid crystal cell. The obtained liquid crystal cell constitutes an IPS mode liquid crystal display element. Thereafter, the obtained liquid crystal cell was heated at 120° C. for 10 minutes, thereby obtaining a liquid crystal display element.

(Evaluation of initial alignment) Using a polarizing microscope, set the polarizing plate to crossed nicol, fix the liquid crystal cell in a state where the brightness is minimum, and rotate the liquid crystal cell 1° from this state to observe the alignment state of the liquid crystal. When alignment defects such as unevenness and weak domains are not observed or are very slight, it is defined as "good", and when it is clearly observed, it is defined as "poor" and evaluated.

(Measurement of V-T curve and evaluation of drive threshold voltage, maximum brightness voltage, and transmittance) Set up a white LED backlight and a luminance meter so that the optical axis is aligned, and set up a liquid crystal cell (liquid crystal display element) equipped with a polarizing plate so that the brightness becomes minimum. Apply a voltage up to 8V at intervals of 1V and measure the brightness of the voltage. This implements the measurement of the V-T curve. Start applying voltage from a state where no voltage is applied, and estimate the voltage value (Vth) when the maximum transmitted brightness is 10%. The value of the voltage (Vmax) at which the brightness reaches maximum is estimated from the obtained V-T curve. In addition, the maximum transmittance (Tmax) is estimated by setting the transmittance brightness of a liquid crystal cell with no voltage applied and 100% in parallel polarization (parallel nicol) and comparing it with the maximum transmittance brightness of the V-T curve.

(Measurement of response time (Ton, Toff)) Using the device used to measure the V-T curve mentioned above, connect the luminance meter to the oscilloscope, and measure the response speed (Ton) when the voltage reaches the maximum brightness and the response speed (Toff) when the voltage returns to 0V.

(Measurement of Azimuth Anchor Strength (A ₂ )) The azimuth anchor strength A ₂ and _SA of strongly anchored horizontal alignment films SE-6414 and NRB-U973 are values separately measured using the torque balance method. The azimuthal anchoring strength A _{2, WA} of the weakly anchored liquid crystal alignment film is measured using the driving threshold voltage (Vth) obtained from the VT curve of the liquid crystal cell produced above, and is obtained by the following formulas (eq2) and (eq3) . In addition, when the azimuthal anchoring strength is less than 10 ^-5 [J/m ² ], it is defined as a weakly anchored liquid crystal alignment film, and when it is greater than 10 ^-4 [J/m ² ], it is defined as a strongly anchored horizontal alignment film.

[Number 2]

[Number 3] Here, V _th,SA represents the driving threshold voltage of the strongly anchored liquid crystal cell, V _th,WA represents the driving threshold voltage of the weakly anchored liquid crystal cell, l is the distance between the comb electrodes, d is the unit cell gap, and K ₂ is The torsional elastic constant of liquid crystal, ε ₀ is the dielectric constant of liquid crystal in vacuum, and Δε is the dielectric anisotropy of liquid crystal. The above formula eq3 is originally a calculation formula when weakly anchored liquid crystal alignment films are used on two substrates. Therefore, the correct azimuthal anchoring strength of the weakly anchored liquid crystal alignment film cannot be calculated. Instead, the azimuth angle of the weakly anchored liquid crystal alignment film is used. An approximation of anchor strength is used.

<Evaluation of unit cell characteristics using photoalignment> (Evaluation results of weakly anchored IPS characteristics) Table 6 shows the contents of the examples and the evaluation results. Table 6 also shows the measurement results of the azimuthal anchoring strength (A ₂ ) of the liquid crystal alignment film on the IPS substrate side.

[Table 6]

From Examples 1 to 26 and Comparative Example 1, it can be observed that the transmittance is improved, the driving voltage is lowered, and the azimuthal anchoring energy is about 2.7×10 ^-6 . Therefore, it can be seen that by using the polymer alloy of the present invention, weak anchoring properties that are equivalent to or greater than those of the weakly anchored liquid crystal alignment agent produced by the method described in Patent Document 3 can be obtained.

The polymer alloy of the present invention is composed of components that exhibit weak anchoring properties and components that do not exhibit weak anchoring properties (Comparative Example 1 and Comparative Example 4), and both exhibit good weak anchoring properties. It is believed that this is because the components showing weak anchorage phase separate during the coating and calcining steps and segregate on the outermost surface of the liquid crystal alignment film.

From Examples 3 to 5 and Comparative Example 4, it can be seen that regardless of the ratio of components that exhibit weak anchoring properties to components that do not exhibit weak anchoring properties, they all exhibit good weak anchoring properties. From this, it can be said that the ratio of components that exhibit weak anchoring properties to components that do not exhibit weak anchoring properties is not particularly limited. However, it is considered that if the ratio of components that do not exhibit weak anchoring properties is too high, the characteristics will deteriorate, so it is still necessary to use an appropriate ratio. ratio to mix.

It can be seen from Examples 1 and 26 that higher transmittance can be obtained by disposing a weakly anchored liquid crystal alignment film on the opposite substrate side. This is due to the fact that a higher phase difference change can be obtained before and after driving the liquid crystal, and the actual film thickness of the driven liquid crystal becomes larger. Therefore, it can be seen that in order to obtain high transmittance, the liquid crystal or the cell gap is usually designed so that the product of the birefringence difference (Δn) of the liquid crystal and the cell gap (D) becomes about 300nm. Even if the above value is 300nm or less, it can still It exhibits high transmittance, so it can achieve further high-speed response. It is also effective in improving imprinting and contrast.

From Examples 22 to 25, it can be said that they all exhibit good weak anchoring properties. Two different weak anchoring components and a thickening component (RSM) can be used, and other than the weak anchoring component and the thickening component (RSM) can also be used. The third ingredient. In particular, when using a third component other than the thickening component (RSM), the use of polyamic acid or polyimide is considered to be beneficial from the viewpoint of resistance value control and mechanical strength of the film.

<Evaluation of unit cell characteristics using frictional alignment> (Evaluation results of weakly anchored IPS characteristics) Table 7 shows the contents of the examples and the evaluation results. Table 7 also shows the measurement results of the azimuthal anchoring strength (A ₂ ) of the liquid crystal alignment film on the IPS substrate side.

[Table 7]

From Examples 27 to 52 and Comparative Example 6, it can be observed that the transmittance is improved, the driving voltage is lowered, and the azimuth anchoring energy is about 2.7×10 ^-6 . Therefore, it can be seen that by using the polymer alloy of the present invention, good weak anchoring properties can be obtained regardless of the alignment treatment method.

It can be seen from Examples 27 and 52 that higher transmittance can be obtained by arranging a weakly anchored liquid crystal alignment film on the opposite substrate side. This study teaches that by arranging a weakly anchored liquid crystal alignment film on the opposite substrate side, a higher phase difference change can be obtained before and after driving the liquid crystal. The reason is due to the actual film thickness expansion of the driveable liquid crystal. Therefore, it can be seen that in order to obtain high transmittance, the liquid crystal or the cell gap is usually designed so that the product of the birefringence difference (Δn) of the liquid crystal and the cell gap (D) becomes about 300nm. Even if the above value is 300nm or less, it can still It exhibits high transmittance, so it can achieve further high-speed response. It is also effective in improving imprinting and contrast.

(Evaluation of coatability using spin coating) The polymers obtained in the above synthesis examples were put into a 20 mL vial in such a combination and ratio as shown in Table 8, and then the solid content concentration was 6 mass%, and BCA/NMP=8/2 (mass Dilute with a mixed solvent (than) and stir at room temperature for 12 hours. The coatability was evaluated by observing the state of the organic film after the obtained diluted solution was applied on an alkali-free glass substrate by spin coating and dried on a hot plate at 80° C. for 2 minutes. In terms of the evaluation criteria, those that produce many defects, whitening, or streaks are defined as "poor", those that can be coated evenly but with some defects are defined as "slightly good", those that can be coated evenly without any Those with defects are defined as "good". The results are shown in Table 8.

(Evaluation of coating properties using flexographic printing) The polymers obtained in the above synthesis examples were put into a 20 mL vial in such a combination and ratio as shown in Table 8, and then the solid content concentration was 6 mass%, and NMP/BCA=6/4 (mass) The mixture was diluted with a mixed solvent (ratio) and stirred at room temperature for 12 hours to obtain a liquid crystal alignment agent. The obtained liquid crystal alignment agent was subjected to flexographic printing (flexographic printing machine manufactured by KOMURA-TECH, substrate: 100mm×100mm Cr evaporation substrate, printing speed: 20m/min, printing pressure: 0.12mm, printing operation time :50sec, anilox roller: #350-28μm, printing plate: #600 mesh, dot opening rate 25%, mesh angle 52°, printing area 80mm×80mm, leveling time: 40sec, drying conditions: 80℃-120s, Evaluation of coatability under main calcination conditions: 230°C･1200sec). When the film can be formed evenly without defects, it is defined as "good". When slight coating defects are observed, but the film can be formed relatively uniformly, it is defined as "slightly good". When there are many coating defects, it is defined as "poor" ”. The results are shown in Table 8.

[Table 8]

It can be seen from Examples 53 to 77 and Comparative Example 11 that the coating properties can be optimized by mixing the polymer (RSM) of the present invention. In particular, the polymer alloys shown in Examples 53 to 55, 57 to 62, 65 to 75, and 77 exhibit good coating properties. It is presumed that the viscosity of the varnish is increased by blending it with a polymer with good coating properties, thereby optimizing the coating uniformity. In addition, liquid crystal alignment films are often manufactured using coating solvents containing NMP, and it is expected that coating with NMP solvents will be of great benefit. [Industrial applicability]

According to the present invention, a stable weakly anchored film can be produced in an extremely simple method compared to the conventional technology. Therefore, in actual industrialization, the step load imposed on the weakly anchored IPS manufacturing can be reduced and the productivity can be improved. Furthermore, by using the materials and methods of the present invention, it is possible to suppress the occurrence of the pretilt angle associated with narrowing the unit cell gap, and at the same time, compared with the conventional technology, it is possible to implement high-speed response at voltage OFF, reduce burn-in, and achieve low-temperature environments. With its high backlight transmittance and low-voltage drive, it can provide materials and transverse electric field liquid crystal display elements that can stably exhibit excellent characteristics.

1: Transverse electric field liquid crystal display element 2: Comb electrode substrate 2a:Substrate 2b: Linear electrode 2c: Liquid crystal alignment film 2d:Substrate 2e: Surface electrode 2f: Insulating film 2g: Line electrode 2h: Liquid crystal alignment film 3: LCD 4: Opposite substrate 4a: Liquid crystal alignment film 4b:Substrate L: Power line

[Fig. 1] is a schematic cross-sectional view showing an example of a horizontal electric field liquid crystal display element of the present invention. [Fig. 2] is a schematic cross-sectional view showing another example of the horizontal electric field liquid crystal display element of the present invention.

1: Transverse electric field liquid crystal display element

2: Comb electrode substrate

2a:Substrate

2b: Linear electrode

2c: Liquid crystal alignment film

3: LCD

4: Opposite substrate

4a: Liquid crystal alignment film

4b:Substrate

L: Power line

Claims (11)

A weakly anchored liquid crystal alignment agent is used to form the liquid crystal alignment film in a liquid crystal cell having a liquid crystal and a liquid crystal alignment film. It contains a polymer having a structural unit represented by the following formula (1) and a component that exhibits weak anchorage. ; In formula (1), R ₁ and R ₂ each independently represent a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 3 carbon atoms, and X represents -OR _a , -N(R _a )(R _b ), or - SR _a , where R _a represents a hydrogen atom or a monovalent organic group, and R _b represents a monovalent group. The weakly anchored liquid crystal alignment agent of claim 1, wherein X in the formula (1) is a base selected from the following structures; In the formula, Y represents an oxygen atom or a sulfur atom, R ₁ represents a hydrogen atom or an alkyl group with 1 to 13 carbon atoms that may also contain a branched or cyclic structure, and R ₂ represents a linear or branched chain with 1 to 5 carbon atoms. Alkyl group, R ₃ represents a single bond or an alkylene group having 1 to 13 carbon atoms which may contain a branched structure or a cyclic structure, R ₄ represents an alkyl group having 1 to 13 carbon atoms which may contain a branched structure or a cyclic structure. , m represents an integer from 0 to 5, n represents an integer from 1 to 5; when there are multiple R ₁ , R ₂ , R ₄ or Y, they may be the same or different respectively; * represents a bonding site. The weakly anchored liquid crystal alignment agent of claim 1, wherein the component exhibiting weak anchorage contains at least one selected from the group consisting of the following polymer A, polymer B and polymer C; Polymer A: a copolymer having block segments (A) that are compatible with the liquid crystal, and block segments (B) that are incompatible with the liquid crystal or insoluble in the liquid crystal by calcination; Polymer B: a graft copolymer having a dry polymer and a branch polymer bonded to the dry polymer as a side chain of the dry polymer, and the branch polymer is compatible with the liquid crystal and the dry polymer The polymer is incompatible with the liquid crystal or is a graft copolymer incompatible with the liquid crystal by calcination; Polymer C: a polymer having polymer units compatible with the liquid crystal and reacting with the polymer having the structural unit represented by formula (1) by heating; The weakly anchored liquid crystal alignment agent of claim 3, wherein the block segment (A) in the polymer A contains a compound selected from a compound represented by the following formula (2), a compound represented by the following formula (3), At least one of the group consisting of the compound represented by formula (4) and the compound represented by the following formula (5) is used as a constituent component, and the block segment (B) in the polymer A contains the following formula (6) The compounds represented serve as constituent components; In formula (2), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, X represents a single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, or thioether bond, and R ₁ represents an alkyl group with 1 to 20 carbon atoms that can be inserted into a bonding group, and n is an integer from 1 to 2; when n is 2, the two X and R ₁ can be the same or different respectively; In formula (3), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, S represents a single bond or a saturated hydrocarbon group having 1 to 6 carbon atoms that may be inserted into a bonding group, and T represents the following formula (3-T) To represent an organic group, n is an integer from 1 to 2; when n is 2, the two Ts can be the same or different; however, when n is 2, S represents the carbon number of 1 to 6 that can also be inserted into the bonding group. The saturated hydrocarbon group; In the formula (3-T), * represents _the bonding site; (R ₂ )-, -Si(R ₃ )(R ₄ )-O-, and -N(R ₅ )-, and R ₁ and R ₂ each independently represent an alkyl group bonded to Si , and R ₃ and R ₄ each independently represent an alkyl group bonded to Si, and R ₅ represents a hydrogen atom or alkyl group bonded to N, and Cy represents a non-aromatic cyclic group with 6 to 20 members; In formula (4), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, R ₁ represents a linear or branched aliphatic hydrocarbon group having 1 to 10 carbon atoms, and the three Xs each independently represent a hydrogen atom or The following formula (4-X); however, at least one of the three Xs expresses the formula (4-X); In formula (4-X), Y represents a single bond, -O-, -S- or -N(R)-, and R represents a hydrogen atom bonded to N or an alkyl group with 1 to 4 carbon atoms, and * represents Bonding site; R ₂ , R ₃ , and R ₄ each independently represent an alkyl group with 1 to 6 carbon atoms or an aromatic hydrocarbon group that may have a substituent; In formula (5), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, R ₁ to R ₃ each independently represents a single bond or an alkylene group having 1 to 6 carbon atoms that may be inserted into a bonding group, Ar represents an aromatic hydrocarbon group that may have a substituent, X ₁ and X _{2 each} independently represents a hydrogen atom or an aromatic hydrocarbon group that may have a substituent, R ₁ X ₁ and R ₂ X ₂ are bonded to R ₁ The carbon atoms _of R ₂ X ₂ can also form _a ring together; _however , the total carbon number of _{R 1} In formula (6), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, n is an integer from 1 to 2; Z represents a group represented by the following formula (6-Z); when n is 2, two Zs can They can be the same or different; In formula (6-Z), L represents a group selected from the group consisting of trialkoxysilyl group, isocyanate group, blocked isocyanate group, epoxy group, oxetanyl group, vinyl group, allyl group, and tetrazolinyl group. Amine group, protected amine group, aniline group, protected aniline group, hydroxyl group, protected hydroxyl group, phenol group, protected phenol group, thiol group, protected thiol group, thiophenol group, protected thiophenol group, aldehyde group, carboxyl group , maleimide group, N-hydroxysuccinimide ester group, aromatic hydrocarbon group with 5 to 18 carbon atoms in the bonding group can also be inserted, aromatic hydrocarbon group with 5 to 18 carbon atoms in the bonding group can also be inserted Heterocyclic group, cinnamic acid group, cinnamic acid aromatic ester group, cinnamic acid alkyl ester group, cinnamon group, phenyl benzoate group, azophenyl group, N-benzylidene anilinyl group, distyryl group, and Functional group in the group consisting of tolanyl; J represents a single bond or an aliphatic hydrocarbon group with 1 to 6 carbon atoms; K when bonded to an aromatic hydrocarbon group represents a single bond, ether bond, or ester bond , the connecting group of amide bond, urea bond, urethane bond, and thioether bond, otherwise it represents a single bond; * represents the bonding site; m represents an integer from 1 to 3; m is 2 or 3, multiple K and L can be the same or different; however, when J is a single bond, m is 1. The weakly anchored liquid crystal alignment agent of claim 3, wherein the branched polymer in the polymer B comes from the polymer monomer represented by the following formula (7); In the formula (7), P represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and Q represents a monomer obtained by polymerizing at least one or more monomers among the compounds represented by the following formulas (2) to (5). In the obtained structure, n is an integer from 1 to 2; when n is 2, the two Qs can be the same or different; In formula (2), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, X represents a single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, or thioether bond, and R ₁ represents an alkyl group with 1 to 20 carbon atoms that can be inserted into a bonding group, and n is an integer from 1 to 2; when n is 2, the two X and R ₁ can be the same or different respectively; In formula (3), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, S represents a single bond or a saturated hydrocarbon group having 1 to 6 carbon atoms that may be inserted into a bonding group, and T represents the following formula (3-T) To represent an organic group, n is an integer from 1 to 2; when n is 2, the two Ts can be the same or different; however, when n is 2, S represents the carbon number of 1 to 6 that can also be inserted into the bonding group. The saturated hydrocarbon group; In the formula (3-T), * represents _the bonding site; (R ₂ )-, -Si(R ₃ )(R ₄ )-O-, and -N(R ₅ )-, and R ₁ and R ₂ each independently represent an alkyl group bonded to Si , and R ₃ and R ₄ each independently represent an alkyl group bonded to Si, and R ₅ represents a hydrogen atom or alkyl group bonded to N, and Cy represents a non-aromatic cyclic group with 6 to 20 members; In formula (4), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, R ₁ represents a linear or branched aliphatic hydrocarbon group having 1 to 10 carbon atoms, and the three Xs each independently represent a hydrogen atom or The following formula (4-X); however, at least one of the three Xs expresses the formula (4-X); In formula (4-X), Y represents a single bond, -O-, -S- or -N(R)-, and R represents a hydrogen atom bonded to N or an alkyl group with 1 to 4 carbon atoms, and * represents Keying part. R ₂ , R ₃ , and R ₄ each independently represent an alkyl group having 1 to 6 carbon atoms or an aromatic hydrocarbon group that may have a substituent; In formula (5), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, R ₁ to R ₃ each independently represents a single bond or an alkylene group having 1 to 6 carbon atoms that may be inserted into a bonding group, Ar represents an aromatic hydrocarbon group that may have a substituent, X ₁ and X _{2 each} independently represents a hydrogen atom or an aromatic hydrocarbon group that may have a substituent, R ₁ X ₁ and R ₂ X ₂ are bonded to R ₁ And the carbon atoms of R ₂ X ₂ can also form a ring together. However, the total carbon number of R ₁ X ₁ , R ₂ X ₂ and R ₃ is 1 or more. The weakly anchored liquid crystal alignment agent of claim 3, wherein the dry polymer in the polymer B contains a compound represented by the following formula (6) as a constituent component; In formula (6), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, n is an integer from 1 to 2; Z represents a group represented by the following formula (6-Z); when n is 2, two Zs can They can be the same or different; In formula (6-Z), L represents a group selected from the group consisting of trialkoxysilyl group, isocyanate group, blocked isocyanate group, epoxy group, oxetanyl group, vinyl group, allyl group, and tetrazolinyl group. Amine group, protected amine group, aniline group, protected aniline group, hydroxyl group, protected hydroxyl group, phenol group, protected phenol group, thiol group, protected thiol group, thiophenol group, protected thiophenol group, aldehyde group, carboxyl group , maleimide group, N-hydroxysuccinimide ester group, aromatic hydrocarbon group with 5 to 18 carbon atoms in the bonding group can also be inserted, aromatic hydrocarbon group with 5 to 18 carbon atoms in the bonding group can also be inserted Heterocyclic group, cinnamic acid group, cinnamic acid aromatic ester group, cinnamic acid alkyl ester group, cinnamon group, phenyl benzoate group, azophenyl group, N-benzylidene anilinyl group, distyryl group, and Functional group in the group consisting of diphenylethynyl group; J represents a single bond or an aliphatic hydrocarbon group with 1 to 6 carbon atoms; K when bonded to an aromatic hydrocarbon group represents a single bond, ether bond, ester bond, amide bond, urea bond, urethane bond, and thioether bond. Otherwise, it represents a single bond; * represents the bonding site; m represents an integer from 1 to 3; when m is 2 or 3 , multiple K and L can be the same or different; however, when J is a single bond, m is 1. The weakly anchored liquid crystal alignment agent of claim 3, wherein the polymer C is a polymer represented by the following formula (8); In the formula (8), A represents a polymer selected from the following formulas (8-A-1) to (8-A-16) that reacts with the polymer having the structural unit represented by the formula (1) by heating. An n-valent organic group with a molecular weight of 300 or less; Q is a divalent polymer containing at least one selected from the group consisting of compounds represented by the following formulas (2) to (5) as a constituent component and compatible with the liquid crystal unit; R is a molecular weight of 500 selected from the following formulas (8-R-1) to (8-R-11) that does not react with the polymer having the structural unit represented by formula (1) by heating. The following monovalent organic groups; n is an integer from 1 to 2; when n is 2, the two Q and R can be the same or different respectively; In formulas (8-A-1) to (8-A-16), R ₁ and R ₂ each independently represent a hydrogen atom or a linear or branched alkyl group with 1 to 12 carbon atoms, and R ₃ and R ₄ each independently represent Ground represents a single bond or a linear or branched alkylene group with 1 to 12 carbon atoms; X represents an oxygen atom or a sulfur atom; * represents a bonding site; In formulas (8-R-1) to (8-R-11), R ₁ and R ₂ each independently represent a hydrogen atom or a linear or branched alkyl group with 1 to 12 carbon atoms, and R ₃ and R ₄ each independently represent Ground represents a single bond or a linear or branched alkylene group with 1 to 12 carbon atoms; * represents the bonding site; In formula (2), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, X represents a single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, or thioether bond, and R ₁ represents an alkyl group with 1 to 20 carbon atoms that can be inserted into a bonding group, and n is an integer from 1 to 2; when n is 2, the two X and R ₁ can be the same or different respectively; In formula (3), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, S represents a single bond or a saturated hydrocarbon group having 1 to 6 carbon atoms that may be inserted into a bonding group, and T represents the following formula (3-T) To represent an organic group, n is an integer from 1 to 2; when n is 2, the two Ts can be the same or different; however, when n is 2, S represents the carbon number of 1 to 6 that can also be inserted into the bonding group. The saturated hydrocarbon group; In formula (3-T), * represents a bonding site. X is selected from the group consisting of single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, thioether bond, -Si(R ₁ )(R ₂ )-, -Si(R ₃ )(R ₄ ) -O-, and -N(R ₅ )- bonding groups, and R ₁ and R ₂ each independently represent an alkyl group bonded to Si, and R ₃ and R ₄ each independently represent an alkyl group bonded to Si is an alkyl group, and R ₅ represents a hydrogen atom or alkyl group bonded to N, and Cy represents a non-aromatic cyclic group with 6 to 20 members; In formula (4), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, R ₁ represents a linear or branched aliphatic hydrocarbon group having 1 to 10 carbon atoms, and the three Xs each independently represent a hydrogen atom or The following formula (4-X); however, at least one of the three Xs expresses the formula (4-X); In formula (4-X), Y represents a single bond, -O-, -S- or -N(R)-, and R represents a hydrogen atom bonded to N or an alkyl group with 1 to 4 carbon atoms, and * represents Bonding site; R ₂ , R ₃ , and R ₄ each independently represent an alkyl group with 1 to 6 carbon atoms or an aromatic hydrocarbon group that may have a substituent; In formula (5), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, R ₁ to R ₃ each independently represents a single bond or an alkylene group having 1 to 6 carbon atoms that may be inserted into a bonding group, Ar represents an aromatic hydrocarbon group that may have a substituent, X ₁ and X _{2 each} independently represents a hydrogen atom or an aromatic hydrocarbon group that may have a substituent, R ₁ X ₁ and R ₂ X ₂ are bonded to R _{1 The} carbon atoms of R ₂ X ₂ may also form _a ring together; however, _the total carbon number of _{R 1} The weakly anchored liquid crystal alignment agent of claim 4, wherein M in the formula (2) is any structure represented by the following, M in the formula (3) is any structure represented by the following, the formula M in (4) is any structure represented by the following; M in formula (5) is any structure represented by the following; In the formula, R ₁ and R ₂ independently represent a hydrogen atom or a linear or branched alkyl group with 1 to 12 carbon atoms, and X, Y and Z respectively independently represent an oxygen atom or a sulfur atom; *, * ¹ and * ² Indicates a bonding site, and either * ¹ or * ² may be substituted by a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms; n represents an integer from 1 to 5. The weakly anchored liquid crystal alignment agent of claim 1, wherein the polymer having the structural unit represented by formula (1) further has the structural unit represented by the following formula (9); In formula (9), R ₃ , R ₄ , R ₅ , and R ₆ each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, -OC(=O)-R, -C(=O)- OR, -OR, or phenyl, and R represents an alkyl group having 1 to 6 carbon atoms. A liquid crystal display element obtained by using the weakly anchored liquid crystal alignment agent according to any one of claims 1 to 9. Such as the liquid crystal display element of claim 10, which is a transverse electric field liquid crystal display element.