TWI696647B - Liquid crystal alignment agent, liquid crystal alignment film, liquid crystal element, method for manufacturing liquid crystal alignment film, polymer and diamine - Google Patents

Abstract

The present invention provides a liquid crystal alignment agent that can obtain a liquid crystal element that exhibits good liquid crystal alignment even when the exposure amount is reduced in the photoalignment step, and is excellent in electrical characteristics and contrast characteristics. The liquid crystal alignment agent contains a polymer [P] having a partial structure represented by the following formula (1) in the main chain.

Description

Liquid crystal alignment agent, liquid crystal alignment film, liquid crystal element, method for manufacturing liquid crystal alignment film, polymer and diamine

The invention relates to a method for manufacturing a liquid crystal alignment agent, a liquid crystal alignment film, a liquid crystal element, a liquid crystal alignment film, a polymer and a diamine.

In liquid crystal display elements widely used in televisions, mobile devices, various monitors, etc., liquid crystal alignment films have been used to control the alignment of liquid crystal molecules in liquid crystal cells. Conventionally, as a method of producing a liquid crystal alignment film, a method of rubbing an organic film, a method of obliquely vapor-depositing silicon oxide, a method of forming a monomolecular film having a long-chain alkyl group, and a photosensitive organic film The method of light irradiation (light alignment method), etc. Among these, the photo-alignment method can provide uniform liquid crystal alignment to the photosensitive organic film while suppressing the generation of static electricity and dust, and can also achieve precise control of the liquid crystal alignment direction. Therefore, various researches (such as Refer to Patent Document 1 to Patent Document 3). [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 06-287453 [Patent Document 2] Japanese Patent Laid-Open No. 2003-307736 [Patent Document 3] Japanese Patent Laid-Open No. 09-297313

[Problems to be Solved by the Invention] However, the conventionally known liquid crystal alignment film materials for optical alignment are not sufficiently light sensitive, and in order for the organic film to exhibit good liquid crystal alignment, a large amount of cumulative exposure is required. Therefore, when forming the liquid crystal alignment film, a lot of process time and cost may be consumed. In addition, in recent years, large-screen and high-definition LCD TVs have become the main body. In addition, the popularization of small display terminals such as smartphones and tablet personal computers (PCs) has been promoted. The requirements for further improvement. Against this background, liquid crystal panels showing good electrical characteristics and display quality have become more important than before.

The present invention was made in view of the above circumstances, and one of the objects is to provide a liquid crystal alignment that can obtain a liquid crystal element that exhibits good liquid crystal alignment even when the exposure amount is reduced in the optical alignment step, and is excellent in electrical characteristics and contrast characteristics Agent. [Technical means to solve the problem]

The inventors have conducted active research in order to achieve the above-mentioned problems of the prior art, and as a result, have found that by using a polymer having a specific partial structure in the polymer component of the liquid crystal alignment agent, the above-mentioned problems can be solved, and the present invention has been completed. invention. Specifically, the present invention provides the following liquid crystal alignment agent, liquid crystal alignment film, liquid crystal element, liquid crystal alignment film manufacturing method, polymer, and diamine.

<1> A liquid crystal alignment agent containing a polymer [P] having a partial structure represented by the following formula (1) in the main chain,

（式（1）中，R¹ 為氫原子、氟原子、碳數1～3的烷基、碳數1～3的氟烷基或者與Ar¹ 鍵結而構成環的一部分的二價連結基，R⁴ 為氫原子、氟原子、碳數1～3的烷基、碳數1～3的氟烷基或者與Ar² 鍵結而構成環的一部分的二價連結基；R² 、R³ 、R⁵ 及R⁶ 分別獨立地為氫原子、氟原子、碳數1～3的烷基或者碳數1～3的氟烷基；Ar¹ 及Ar² 分別獨立地為具有芳香環或雜環的環式基或者伸乙炔基，所述環式基也可在環部分具有取代基；「*」表示結合鍵）。[Chem 1]

(In formula (1), R ¹ is a hydrogen atom, a fluorine atom, a C 1-3 alkyl group, a C 1-3 fluoroalkyl group, or a divalent linking group bonded to Ar ¹ to form part of a ring , R ⁴ is a hydrogen atom, a fluorine atom, a C 1-3 alkyl group, a C 1 to 3 fluoroalkyl group, or a divalent linking group bonded to Ar ² to form a part of the ring; R ² , R ³ , R ⁵ and R ⁶ are independently a hydrogen atom, a fluorine atom, a C 1-3 alkyl group or a C 1-3 fluoroalkyl group; Ar ¹ and Ar ² are independently independently having an aromatic ring or heterocyclic ring Cyclic group or ethynyl group, the cyclic group may also have a substituent in the ring portion; "*" represents a bonding bond).

<2> A liquid crystal alignment film formed using the liquid crystal alignment agent of <1>. <3> A liquid crystal element comprising the liquid crystal alignment film of <2>. <4> A method of manufacturing a liquid crystal alignment film, which applies the liquid crystal alignment agent of <1> to a substrate to form a coating film, and irradiates the coating film with radiation. <5> A polymer selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, polyamidide, polyester, and polyether, and having the main chain Partial structure represented by formula (1). <6> A diamine represented by the following formula (2A),

（式（2A）中，R¹ 為氫原子、氟原子、碳數1～3的烷基、碳數1～3的氟烷基或者與Ar¹ 鍵結而構成環的一部分的二價連結基，R⁴ 為氫原子、氟原子、碳數1～3的烷基、碳數1～3的氟烷基或者與Ar² 鍵結而構成環的一部分的二價連結基；R² 、R³ 、R⁵ 及R⁶ 分別獨立地為氫原子、氟原子、碳數1～3的烷基或者碳數1～3的氟烷基；Ar¹ 及Ar² 分別獨立地為具有芳香環或雜環的環式基或者伸乙炔基，所述環式基也可在環部分具有取代基；X¹ 及X² 分別獨立地為單鍵或者二價連結基）。 [發明的效果][Chem 2]

(In formula (2A), R ¹ is a hydrogen atom, a fluorine atom, a C 1-3 alkyl group, a C 1-3 fluoroalkyl group, or a divalent linking group bonded to Ar ¹ to form part of a ring , R ⁴ is a hydrogen atom, a fluorine atom, a C 1-3 alkyl group, a C 1 to 3 fluoroalkyl group, or a divalent linking group bonded to Ar ² to form a part of the ring; R ² , R ³ , R ⁵ and R ⁶ are independently a hydrogen atom, a fluorine atom, a C 1-3 alkyl group or a C 1-3 fluoroalkyl group; Ar ¹ and Ar ² are independently independently having an aromatic ring or heterocyclic ring Cyclic group or ethynyl group, the cyclic group may also have a substituent in the ring portion; X ¹ and X ² are each independently a single bond or a divalent linking group). [Effect of invention]

According to the liquid crystal alignment agent containing the polymer [P], a liquid crystal alignment film exhibiting good liquid crystal alignment can be obtained even if the exposure amount is reduced in the photo alignment step. In addition, a liquid crystal element having excellent electrical characteristics and contrast characteristics can be obtained.

（式（1）中，R¹ 為氫原子、氟原子、碳數1～3的烷基、碳數1～3的氟烷基或者與Ar¹ 鍵結而構成環的一部分的二價連結基，R⁴ 為氫原子、氟原子、碳數1～3的烷基、碳數1～3的氟烷基或者與Ar² 鍵結而構成環的一部分的二價連結基；R² 、R³ 、R⁵ 及R⁶ 分別獨立地為氫原子、氟原子、碳數1～3的烷基或者碳數1～3的氟烷基；Ar¹ 及Ar² 分別獨立地為具有芳香環或雜環的環式基或者伸乙炔基，所述環式基也可在環部分具有取代基；「*」表示結合鍵）。Hereinafter, each component contained in the liquid crystal aligning agent of this disclosure, and other components arbitrarily mixed as needed are demonstrated. <Polymer [P]> The liquid crystal alignment agent of the present disclosure contains a polymer [P] having a partial structure represented by the following formula (1) (hereinafter also referred to as "specific partial structure"). [Chemical 3]

(In formula (1), R ¹ is a hydrogen atom, a fluorine atom, a C 1-3 alkyl group, a C 1-3 fluoroalkyl group, or a divalent linking group bonded to Ar ¹ to form part of a ring , R ⁴ is a hydrogen atom, a fluorine atom, a C 1-3 alkyl group, a C 1 to 3 fluoroalkyl group, or a divalent linking group bonded to Ar ² to form a part of the ring; R ² , R ³ , R ⁵ and R ⁶ are independently a hydrogen atom, a fluorine atom, a C 1-3 alkyl group or a C 1-3 fluoroalkyl group; Ar ¹ and Ar ² are independently independently having an aromatic ring or heterocyclic ring Cyclic group or ethynyl group, the cyclic group may also have a substituent in the ring portion; "*" represents a bonding bond).

Examples of the C 1-3 alkyl groups in R ¹ to R ⁶ of the formula (1) include methyl, ethyl, and propyl groups, and these may be linear or branched. Specific examples of the case where R ¹ to R ⁶ are fluoroalkyl groups having 1 to 3 carbon atoms include, for example, trifluoromethyl, 2,2,2-trifluoroethyl, and the like. When R ¹ is a divalent linking group, it is preferable that R ¹ forms a fused ring together with Ar ¹ by bonding to the ring portion of Ar ¹ . In addition, when R ² is a divalent linking group, it is preferred that R ² forms a fused ring together with Ar ² by bonding to the ring portion of Ar ² . Specific examples in the case where R ¹ and R ⁴ are divalent linking groups include, for example, -CO-, a C1-C3 alkanediyl group and the like. Examples of the alkanediyl group include methylene, ethylidene, and propanediyl groups, and these may be linear or branched. In terms of improving the photosensitivity of the polymer [P], the divalent linking group of R ¹ and R ⁴ is preferably -CO- or methylene. Among them, R ² , R ³ , R ⁵ and R ^{6 are} preferably a hydrogen atom or a methyl group.

The cyclic groups of Ar ¹ and Ar ² are n-valent groups obtained by removing n (n is 2 or 3) hydrogen atoms from the aromatic ring or heterocyclic ring part. Examples of the aromatic ring included in the cyclic group include benzene ring, naphthalene ring, and anthracene ring. Examples of the heterocyclic ring include pyridine ring, pyrimidine ring, pyrazine ring, quinoline ring, imidazole ring, and piperidine. Ring, piperazine ring, etc. Examples of the substituent that the aromatic ring or heterocyclic ring portion may have include a halogen atom (fluorine atom, etc.), a C 1-3 alkyl group, or a C 1-3 alkoxy group. From the viewpoint of electrical characteristics and affinity with liquid crystals, Ar ¹ and Ar ^{2 are} preferably substituted or unsubstituted phenylene groups, and more preferably 1,4-phenylene groups.

The polymer [P] has a specific partial structure in the main chain. Here, in this specification, the "backbone" of the polymer refers to the "backbone" portion including the longest atomic chain in the polymer. In addition, the "backbone" part is allowed to contain a ring structure. Therefore, "having a specific partial structure in the main chain" means that the structure constitutes a part of the main chain. In the present disclosure, the main chain of the polymer [P] is not particularly limited, and the polymer [P] is preferably selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, polyamide, polyester, and poly At least one of the group consisting of ethers. Hereinafter, preferred specific examples of the polymer [P] contained in the liquid crystal alignment agent of the present disclosure will be described in detail.

<Polyamino acid> Polyamide acid (hereinafter also referred to as "polyamide acid [P]") as the polymer [P] can be obtained by reacting tetracarboxylic dianhydride and diamine, for example. In particular, a method using a diamine having a specific partial structure (hereinafter also referred to as "specific diamine") is preferably used.

(Tetracarboxylic dianhydride) Examples of the tetracarboxylic dianhydride used in the synthesis of polyamide [P] include aliphatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, and aromatic tetracarboxylic dianhydride. Acid dianhydride, etc. As specific examples of these tetracarboxylic dianhydrides, aliphatic tetracarboxylic dianhydrides include, for example, butane tetracarboxylic dianhydride, ethylenediaminetetraacetic dianhydride, and the like; and alicyclic tetracarboxylic dianhydrides, for example, can be cited. : 1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2,4,5 -Cyclohexanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 1,3,3a,4, 5,9b-Hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-c]furan-1,3-dione, 1,3,3a ,4,5,9b-hexahydro-8-methyl-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-c]furan-1,3- Diketone, 2,4,6,8-tetracarboxybicyclo[3.3.0]octane-2:4,6:8-dianhydride, etc.; aromatic tetracarboxylic dianhydride, for example, pyromellitic acid dianhydride Anhydride, 4,4-(hexafluoroisopropylidene) diphthalic anhydride, p-phenylene bis (trimellitic acid monoester anhydride), 4,4'-oxydiphthalic anhydride, In addition to propylene glycol bistrimellitic anhydride ester, the tetracarboxylic dianhydride described in Japanese Patent Laid-Open No. 2010-97188 can be used.

From the viewpoint of obtaining a film with good photosensitivity and excellent electrical characteristics, the tetracarboxylic dianhydride used in the synthesis of the polyamic acid [P] is preferably included as a member selected from the group consisting of 1, 2, 3, 4-cyclobutane Alkanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2 , At least one specific acid dianhydride in the group consisting of 4,5,5-cyclohexanetetracarboxylic dianhydride and 1,2,3,4-cyclopentanetetracarboxylic dianhydride. The use ratio of these specific acid dianhydrides is preferably 30 mol% or more, and more preferably 40 mol% with respect to the total amount of tetracarboxylic dianhydride used in the synthesis of polyamic acid [P]. The above is more preferably 50 mol% or more. In addition, tetracarboxylic dianhydride may be used alone or in combination of two or more.

（式（2A）中，R¹ ～R⁶ 、Ar¹ 及Ar² 與所述式（1）含義相同；X¹ 及X² 分別獨立地為單鍵或者二價連結基）(Diamine) As a preferred specific example of the specific diamine used in the above reaction, a compound represented by the following formula (2A) and the like can be mentioned. [Chem 4]

(In formula (2A), R ¹ to R ⁶ , Ar ¹ and Ar ² have the same meaning as the above formula (1); X ¹ and X ² are each independently a single bond or a divalent linking group)

In the above formula (2A), the specific examples and preferred examples of R ¹ to R ⁶ and Ar ¹ and Ar ² apply to the description of (1). Examples of the divalent linking group of X ¹ and X ² include a divalent hydrocarbon group having 1 to 20 carbon atoms, and a group including -O-, -CO-, -COO- and the like between the carbon-carbon bonds of the hydrocarbon group. Wait. Preferred specific examples of the specific diamine include compounds represented by the following formula (2), formula (2-3) to formula (2-9), respectively. Among them, the compounds represented by the following formula (2-1), formula (2-3), formula (2-4), and formula (2-5) are particularly preferred. [Chemical 5]

The diamine used in the reaction may be only a specific diamine, or may be used together with a specific diamine without a specific partial structure (hereinafter also referred to as "other diamines"). Other diamines can be classified as: diamines having a group (hereinafter also referred to as a "pretilt angle expressive group") for giving a coating film a function to impart a pretilt angle to liquid crystal molecules; those without a pretilt angle expressive group Diamine. Here, specifically, the "pretilt angle expressive group" includes, for example, an alkyl group having 4 to 20 carbon atoms, a fluoroalkyl group having 4 to 20 carbon atoms, an alkoxy group having 4 to 20 carbon atoms, and 17 carbon atoms. A group having a steroid skeleton of ~51, a group in which a plurality of rings are bonded directly or via a linking group, and the like.

（式（E-1）中，X^I 及X^II 分別獨立地為單鍵、-O-、*-COO-或者*-OCO-（其中，「*」表示與X^I 的結合鍵），R^I 為碳數1～3的烷二基，R^II 為單鍵或者碳數1～3的烷二基，a為0或1，b為0～2的整數，c為1～20的整數，d為0或1；其中，a及b不同時為0）As the diamine having a pretilt-expressing group, an aromatic diamine can be preferably used, and specific examples thereof include, for example, dodecyloxy-2,4-diaminobenzene and hexadecyloxy-2, 4-diaminobenzene, octadecyloxy-2,4-diaminobenzene, tetradecyloxy-2,5-diaminobenzene, cholesteryloxy-3,5-diamine Benzene, cholesteryloxy-3,5-diaminobenzene, cholesteryloxy-2,4-diaminobenzene, 3,5-diaminobenzoic acid cholesteryl ester, 3,5-diaminobenzoic acid cholesteryl ester, 3,5-diaminobenzoic acid lansteryl alkyl ester, 3,6-bis(4-aminobenzyloxy)cholesterane , 3,6-bis(4-aminophenoxy)cholesterane, 1,1-bis(4-((aminophenyl)methyl)phenyl)-4-heptylcyclohexane, N -(2,4-diaminophenyl)-4-(4-heptylcyclohexyl)benzamide, a compound represented by the following formula (E-1), etc. [化6]

(In formula (E-1), X ^I and X ^II are independently a single bond, -O-, *-COO- or *-OCO- (where "*" represents a bond with X ^I ), R ^I is a C1-C3 alkanediyl group, R ^II is a single bond or C1-C3 alkanediyl group, a is 0 or 1, b is an integer of 0-2, and c is an integer of 1-20, d is 0 or 1; where a and b are not 0 at the same time)

Specific examples of the compound represented by the formula (E-1) include, for example, compounds represented by the following formulas (E-1-1) to (E-1-4). [化7]

Examples of the diamine having no pretilt-expressing group include aliphatic diamines such as 1,1-m-xylylenediamine, 1,3-propanediamine, tetramethylenediamine, and pentamethylenediamine. Amine, hexamethylenediamine, etc.; Alicyclic diamines include, for example: 1,4-diaminocyclohexane, 4,4'-methylenebis (cyclohexylamine), 1,3-bis (Aminomethyl) cyclohexane, etc.;

Examples of aromatic diamines include p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfide, 1,5-diaminonaphthalene, and 2 ,2'-Dimethyl-4,4'-diaminobiphenyl, 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl, 4,4'-diamine Diphenyl ether, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 9,9-bis(4-aminophenyl) stilbene, 2,2-bis[4 -(4-aminophenoxy)phenyl]hexafluoropropane, 4,4'-(p-phenylene diisopropylidene)bisaniline, 1,4-bis(4-aminophenoxy) Benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 2,6-diaminopyridine, N,N'-bis(4-aminophenyl)-benzidine, 1,4 -Bis-(4-aminophenyl)-piperazine, 3,5-diaminobenzoic acid, 4-(4'-trifluoromethoxybenzyloxy)cyclohexyl-3,5-di Aminobenzoate, 4-(4'-trifluoromethylbenzoyloxy)cyclohexyl-3,5-diaminobenzoate, 2,4-diamino-N,N- Diallylaniline, 4-aminobenzylamine, 1-(2,4-diaminophenyl)piperazine-4-carboxylic acid, 4-(morpholin-4-yl)benzene-1,3- Diamine, 1,3-bis(N-(4-aminophenyl) piperidinyl)propane, α-amino-ω-aminophenyl alkylene, 4-(2-aminoethyl)aniline , 4,4'-[4,4'-propane-1,3-diylbis(piperidine-1,4-diyl)] diphenylamine, etc.; examples of diamine-based organosiloxanes include: 1, In addition to 3-bis(3-aminopropyl)-tetramethyldisilaxane, the diamine described in Japanese Patent Laid-Open No. 2010-97188 can also be used. In addition, other diamines may be used alone or in combination of two or more.

The liquid crystal alignment agent of the present disclosure can be preferably used to form a liquid crystal alignment film by an optical alignment method, and is particularly preferably applied to a twisted nematic (TN) type or super twisted nematic (STN) Type, co-planar switching (In-Plane Switching, IPS) type, fringe field switching (Fringe Field Switching, FFS) type and other so-called horizontal alignment type liquid crystal display device uses. Therefore, it is preferable to limit the use ratio of the diamine having a pretilt angle expressive group to a fixed value or less. With respect to all the diamines used in the reaction, the use ratio of the diamine having a pretilt angle expressing group is preferably a ratio of 20 mol% or less, more preferably a ratio of 10 mol% or less, and Preferably, it is 5 mol% or less.

The use ratio of the specific diamine is preferably 50 mol% or more, and more preferably 80 mol% or more with respect to the total amount of diamine used in the synthesis of the polyamic acid. By setting the content ratio of the specific diamine to 50 mol% or more, a polyamide having excellent light sensitivity can be obtained. The upper limit of the use ratio of a specific diamine is not particularly limited, and can be arbitrarily selected according to the use ratio of other diamines. In addition, the specific diamine may be used alone or in combination of two or more.

(Synthesis of Polyamic Acid) Polyamic acid [P] can be prepared by using the above-mentioned tetracarboxylic dianhydride and diamine, if necessary, with a molecular weight modifier (for example, monoanhydride, monoamine compound, monoisocyanate compound, etc.) ) Obtained by reacting together. The use ratio of the tetracarboxylic dianhydride and the diamine used for the synthesis reaction of the polyamic acid is preferably 1 equivalent to the amine group of the diamine, and the acid anhydride group of the tetracarboxylic dianhydride becomes a ratio of 0.2 to 2 equivalents. It is more preferably a ratio of 0.8 to 1.2 equivalents.

The synthesis reaction of polyamic acid is preferably carried out in an organic solvent. The reaction temperature at this time is preferably -20°C to 150°C, and the reaction time is preferably 0.1 hour to 24 hours. As the organic solvent used in the reaction, it is preferable to use one or more selected from the group consisting of an aprotic polar solvent and a phenolic vehicle (the first group of organic solvents), or one selected from the first group A mixture of one or more organic solvents and one or more selected from the group consisting of alcohols, ketones, esters, ethers, halogenated hydrocarbons, and hydrocarbons (second group of organic solvents). In the latter case, the use ratio of the organic solvent in the second group is preferably 50% by weight or less, and more preferably 40% by weight relative to the total amount of the organic solvent in the first group and the organic solvent in the second group the following. The use amount (x) of the organic solvent is preferably such that the total amount (y) of tetracarboxylic dianhydride and diamine is 0.1% to 50% by weight relative to the total amount of reaction solution (x+y). . The reaction solution obtained by dissolving the polyamic acid [P] can be directly used for the preparation of the liquid crystal alignment agent, or can be used for the preparation of the liquid crystal alignment agent after separating the polyamic acid [P] contained in the reaction solution.

流程A(Synthesis of Specific Diamine) The specific diamine can be synthesized by a conventional method suitable for combining organic chemistry. For example, the compound represented by the above formula (2) can be synthesized by photodimerization of aminocinnamic acid as shown in the following scheme A, and the carboxyl group is removed. In addition, the compounds represented by the formulas (2-3) to (2-8) can be synthesized by cyclizing the reaction product in the first stage of the following procedure A using sulfuric acid or the like. However, the synthesis formula of a specific diamine is not limited to the above method. [Chem 8]

Process A

<Polyamidate> In the case where the main chain of the polymer [P] is polyamide, the polymer [P] can be obtained, for example, by the following method: [I] The polymer obtained above Method for the reaction of amide acid [P] with an esterifying agent (such as methanol or ethanol, N,N-dimethylformamide diethyl acetal, etc.); [II] Tetracarboxylic acid diester and diamine Preferably in an organic solvent, in a suitable dehydration catalyst (such as halogenated 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholine, carbonyl imidazole , Phosphorus-based condensing agent, etc.); [III] The tetracarboxylic acid diester dihalide and diamine are preferably in an organic solvent, in an appropriate base (such as pyridine, triethylamine, etc. A method of performing the reaction in the presence of a high-grade amine, or alkali metals such as sodium hydride, potassium hydride, sodium hydroxide, potassium hydroxide, sodium, and potassium). The method [II] and the method [III] are preferably methods using a specific diamine.

The polyamic acid ester contained in the liquid crystal alignment agent may have only an amino acid ester structure, or may be a partial esterified product in which an amino acid structure and an amino acid ester structure coexist. The reaction solution obtained by dissolving the polyamic acid ester can be directly used for the preparation of the liquid crystal alignment agent, or can be used for the preparation of the liquid crystal alignment agent after separating the polyamic acid ester contained in the reaction solution.

<Polyimide> When the main chain of the polymer [P] is polyimide, the polymer (hereinafter also referred to as "polyimide [P]") can be obtained by, for example, combining polyimide The acid [P] is obtained by dehydration and ring closure, and by imidization.

Polyimide [P] may be a complete imide compound obtained by dehydrating and ring-closing all the amino acid structures possessed by the polyamic acid as its precursor, or it may be a part of only the amino acid structure Dehydration and ring closure to partially coexist amide imide structure and amide imide ring structure. The imidate rate of the polyimide [P] is preferably 30% or more, more preferably 50% or more, and still more preferably 60% or more. In addition, from the viewpoint of ensuring the solubility of the polymer and improving the coatability, it is preferable to set the imidate ratio to 80% or less, and more preferably to 70% or less. In addition, the imidate ratio is expressed as a percentage of the total number of amide imine ring structures relative to the total number of amide acid structures of polyimide and the number of amide imine ring structures. Here, a part of the imidate ring may be an imidate ring.

The dehydration and ring closure of the polyamic acid is preferably performed by dissolving the polyamic acid in an organic solvent, adding a dehydrating agent and a dehydration ring-closing catalyst to the solution, and heating if necessary. As the dehydrating agent, for example, anhydrides such as acetic anhydride, propionic anhydride, and trifluoroacetic anhydride can be used. The use amount of the dehydrating agent is preferably 0.01 mol to 20 mol relative to 1 mol of the amide structure of the polyamic acid. As the dehydration ring-closure catalyst, for example, tertiary amines such as pyridine, collidine, lutidine, and triethylamine can be used. The use amount of the dehydration ring-closing catalyst is preferably 0.01 mol to 10 mol relative to 1 mol of the dehydrating agent used. Examples of the organic solvent used in the dehydration ring-closure reaction include the organic solvents exemplified as used for the synthesis of polyamic acid. The reaction temperature of the dehydration ring-closure reaction is preferably 0°C to 180°C, and more preferably 10°C to 150°C. The reaction time is preferably 1.0 hour to 120 hours, and more preferably 2.0 hours to 30 hours. The reaction solution containing polyimide can be directly used for the preparation of the liquid crystal alignment agent, or can be used for the preparation of the liquid crystal alignment agent after removing the dehydrating agent and the dehydration ring-closing catalyst from the reaction solution. In addition to this, polyimide can also be obtained by the imidization of polyimide.

The polyamic acid, the polyamic acid ester, and the polyimide as the polymer [P] obtained in the above-described manner are preferably 100 mPa·s when they are made into a solution having a concentration of 20% by weight. The compound having a solution viscosity of 5,000 mPa·s is more preferably a compound having a solution viscosity of 150 mPa·s to 3,500 mPa·s. In addition, the solution viscosity (mPa·s) of the polymer is a good solvent (such as γ-butyrolactone, N-methyl-2-pyrrolidone, etc.) using the E-type rotary viscometer. The value of the prepared polymer solution having a concentration of 20% by weight was measured at 25°C. The polystyrene-equivalent weight average molecular weight (Mw) of the polyamic acid, polyamic acid ester and polyimide determined by gel permeation chromatography (GPC) is preferably 500 ~300,000, more preferably 1,000-200,000.

<Polyamide> Polyamide as the polymer [P] (hereinafter also referred to as "polyamide [P]") can be obtained by, for example, polycondensation reaction of dicarboxylic acid and diamine. Among them, a method using a specific diamine is preferred.

Examples of the diamine used in the reaction include specific diamines and other diamines exemplified in the description of the polyamic acid [P]. In addition, in order to improve the solubility of the polyamide when performing the reaction, it is preferable that the primary amine group of the diamine is protected with a protective group such as a third butoxycarbonyl group and then supplied to the dicarboxylic acid. Reaction. The use ratio of the specific diamine is preferably 50 mol% or more, and more preferably 80 mol% or more with respect to the total amount of diamine used in the synthesis of the polyamide. One type of diamine may be used alone or two or more types may be used in combination.

The dicarboxylic acid is not particularly limited, and examples thereof include oxalic acid, malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, 3,3-diethylsuccinic acid, fumaric acid, Aliphatic dicarboxylic acids such as muconic acid; cyclobutane dicarboxylic acid, 1-cyclobutene dicarboxylic acid, cyclopentane dicarboxylic acid, cyclohexane dicarboxylic acid, etc. having an alicyclic structure Dicarboxylic acid; phthalic acid, isophthalic acid, terephthalic acid, 5-methylisophthalic acid, 4,4'-biphenyl dicarboxylic acid, 4,4'-diphenyl methane di Carboxylic acid, 4,4'-diphenylpropane dicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, 4-carboxycinnamic acid, p-phenylene diacrylic acid, 3,3'-[4, 4'-(methylene di-p-phenylene)] dipropionic acid, 4,4'-[4,4'-(oxydi-p-phenylene)] dibutyric acid, 3,4-di Dicarboxylic acids having aromatic rings, such as phenyl-1,2-cyclobutane dicarboxylic acid and azobenzene-4,4'-dicarboxylic acid. In addition, the dicarboxylic acid may be used alone or in combination of two or more. The dicarboxylic acid is preferably chlorinated with an appropriate chlorinating agent such as thionyl chloride and then supplied to the reaction with the diamine.

The reaction of the dicarboxylic acid and the diamine is preferably carried out in an organic solvent in the presence of a base. The use ratio of the dicarboxylic acid and the diamine in the reaction is preferably 1 equivalent to the amine group of the diamine, and the carboxyl group of the dicarboxylic acid becomes a ratio of 0.2 to 2 equivalents. The reaction temperature at this time is preferably -100°C to 200°C, and the reaction time is preferably 0.5 hour to 48 hours. As the organic solvent, for example, diethyl ether, tetrahydrofuran, dioxane, toluene, methylene chloride, chloroform, dimethylformamide, dimethylacetamide, dimethylsulfoxide, N-methyl -2-pyrrolidone, etc. The use amount of the organic solvent is preferably 400 to 900 parts by weight, and more preferably 500 to 700 parts by weight with respect to 100 parts by weight of the total amount of the dicarboxylic acid dihalide and the diamine. For the base used in the above reaction, the exemplification of the base exemplified in the method [III] of the polyamide can be applied. The use amount of the base is preferably 2 to 4 moles relative to 1 mole of diamine. The reaction solution obtained by dissolving the polyamidoamine [P] can be directly used for the preparation of the liquid crystal alignment agent, or it can be used for the preparation of the liquid crystal alignment agent after separating the polyamide contained in the reaction solution.

Regarding the solution viscosity of the polyamide [P], when it is a solution having a concentration of 10% by weight, it is preferably a solution viscosity of 5 mPa·s to 800 mPa·s, and more preferably 10 mPa·s to 500 mPa·s solution viscosity. In addition, the solution viscosity (mPa·s) of polyamide is prepared with a good solvent (such as γ-butyrolactone, N-methyl-2-pyrrolidone, etc.) that uses polyamide using an E-type rotary viscometer. A value obtained by measuring a polymer solution having a concentration of 10% by weight at 25°C. Regarding the polyamide [P], the polystyrene-equivalent weight average molecular weight (Mw) measured by GPC is preferably 1,000 to 500,000, and more preferably 2,000 to 300,000.

<Polyester> When the main chain of the polymer [P] is polyester, the polymer (hereinafter also referred to as "polyester [P]") may be, for example, a dicarboxylic acid dihalide and a diol Obtained by reaction. Examples of the dicarboxylic acid dihalide used in the reaction include, for example, compounds obtained by chlorinating the dicarboxylic acid exemplified in the synthesis of polyamidoamine with an appropriate chlorinating agent such as thionyl chloride. . The dicarboxylic acid dihalide can be used alone or in combination of two or more.

Regarding the diol used in the reaction, from the viewpoint of liquid crystal alignment, a diol having a specific partial structure can preferably use a diphenol compound. Specific examples of the diol having a specific partial structure include, for example, compounds represented by the following formula (3), formula (3-3) to formula (3-9), and the like. The compound represented by the following formula (3) is preferably a compound represented by the following formula (3-1). [化9]

In the synthesis of polyester [P], as the diol, only a diol having a specific partial structure may be used, or a diol having no specific partial structure (hereinafter also referred to as "other diols") may be used. The use ratio of the diol having a specific partial structure relative to the total amount of the diol used in the synthesis of the polyester is preferably 50 mol% or more, and more preferably 80 mol% or more. In addition, diols may be used alone or in combination of two or more.

The use ratio of the dicarboxylic acid dihalide and the diol in the reaction is preferably 1 equivalent to the hydroxyl group of the diol, and the group "-COX ¹ (X ¹ is a halogen atom)" of the dicarboxylic acid dihalide becomes 0.2 The ratio of equivalent to 2 equivalents. In addition, a polyester amide can be obtained by copolymerizing the diamine used in the polyamide [P] instead of a diol. The reaction of the dicarboxylic acid dihalide and the diol is preferably carried out in an organic solvent in the presence of a base. The reaction temperature at this time is preferably 0°C to 200°C, and the reaction time is preferably 0.5 hour to 48 hours. As the organic solvent and base used in the reaction, the same compounds as those used in the synthesis of polyamide can be used. The reaction solution obtained by dissolving the polyester [P] can be directly used for the preparation of the liquid crystal alignment agent, or can be used for the preparation of the liquid crystal alignment agent after separating the polyester contained in the reaction solution.

Regarding the solution viscosity of the polyester [P], when it is a solution having a concentration of 10% by weight, it preferably has a solution viscosity of 5 mPa·s to 800 mPa·s, and more preferably has a solution viscosity of 10 mPa·s to 500 mPa. ·S solution viscosity. In addition, the solution viscosity (mPa·s) of polyester is prepared using a E-type viscometer, and the concentration of the good solvent (such as γ-butyrolactone, N-methyl-2-pyrrolidone, etc.) using polyester is prepared as The value obtained by measuring 10% by weight of the polymer solution at 25°C. Regarding the polyester [P], the polystyrene-equivalent weight average molecular weight (Mw) measured by GPC is preferably 1,000 to 500,000, and more preferably 2,000 to 300,000.

<Polyether> When the main chain of the polymer [P] is polyether, the polymer (hereinafter also referred to as "polyether [P]") may be obtained by reacting a dihalide and a diol, for example . The dihalide used in the reaction is preferably chloride, bromide or iodide. As the diol, the same compound as that used in the synthesis of polyester [P] can be used. In addition, as the diol, when a diol having a specific partial structure is used in combination with another diol, the description of the polyester [P] can be applied to the use ratio of the diol having a specific partial structure. In the synthesis of the polyether [P], the use ratio of the dihalide to the diol is preferably 1 equivalent to the hydroxyl group of the diol, and the halogen group of the dihalide becomes a ratio of 0.2 to 2 equivalents.

The reaction is preferably carried out in an organic solvent in the presence of a base. The reaction temperature at this time is preferably 0°C to 200°C, and the reaction time is preferably 0.5 hour to 48 hours. As the organic solvent, for example, tetrahydrofuran, dioxane, toluene, methylene chloride, chloroform, dimethylformamide, dimethylacetamide, dimethylsulfoxide, N-methyl-2- Pyrrolidone, etc. The use amount of the organic solvent is preferably 400 to 900 parts by weight, and more preferably 500 to 700 parts by weight relative to 100 parts by weight of the total amount of monomers. As the base used in the reaction, for example, tertiary amines such as pyridine, triethylamine, tripropylamine, and triisopropylamine; lithium hydroxide, sodium hydroxide, potassium hydroxide, lithium hydride, sodium hydride, bis (Trimethylsilyl) lithium amide, tertiary butyl lithium, sodium carbonate, potassium carbonate and other alkali metals. The use amount of the base is preferably 2 to 4 moles relative to 1 mole of diol. The reaction solution obtained by dissolving the polyether [P] can be directly used for the preparation of the liquid crystal alignment agent, or can be used for the preparation of the liquid crystal alignment agent after separating the polyether contained in the reaction solution.

Regarding the solution viscosity of the polyether [P], when it is a solution having a concentration of 10% by weight, it is preferably a solution viscosity of 5 mPa·s to 800 mPa·s, and more preferably 10 mPa·s to 500 mPa ·S solution viscosity. In addition, the solution viscosity (mPa·s) of the polymer (P) is prepared using a E-type rotary viscometer for a good solvent (such as N-methyl-2-pyrrolidone, etc.) using polyether [P]. The value obtained by measuring 10% by weight of the polymer solution at 25°C. Regarding polyether [P], the weight average molecular weight (Mw) in terms of polystyrene measured by GPC is preferably 1,000 to 500,000, and more preferably 2,000 to 300,000. Among the above, the polymer [P] is preferably selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide in terms of excellent heat resistance, mechanical strength, electrical characteristics, transparency, and other characteristics. And at least one of the group consisting of polyamide. In addition, the polymer [P] formulated in the liquid crystal alignment agent may be only one kind or two or more kinds.

<Other Components> The liquid crystal alignment agent of the present disclosure may contain other components than the polymer [P]. Examples of such other components include polymers without a specific partial structure (hereinafter also referred to as "other polymers"), compounds having at least one epoxy group in the molecule, and at least one oxetane in the molecule. Alkyl compounds, functional silane compounds, photopolymerizable compounds, metal chelate compounds, hardening accelerators, surfactants, antioxidants, sensitizers, preservatives, stabilizers, viscosity modifiers, etc. The blending ratio of other components can be appropriately selected according to each compound within a range that does not impair the effects of the present invention.

For example, examples of other polymers include: polyamic acid, polyimide, polyamic acid ester, polyester, polyamide, polysiloxane, polyether, polyaromatic hydrocarbon, cellulose derivative, Polyacetal, polystyrene derivatives, poly(styrene-phenyl maleimide) derivatives, or poly(meth)acrylate-based polymers that do not have a specific partial structure, etc. When other polymers are blended in the liquid crystal alignment agent, the blending ratio is preferably 50% by weight or less relative to the total amount of polymers in the liquid crystal alignment agent, more preferably 0.1% by weight to 40% by weight, and still more preferably 0.1% to 30% by weight.

<Solvent> The liquid crystal alignment agent of the present disclosure is prepared in the form of a liquid composition in which the polymer [P] and other components used as needed are preferably dispersed or dissolved in an appropriate solvent.

Examples of the organic solvent used include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 1,2-dimethyl-2-imidazolidinone, γ-butyrolactone, and γ -Butyrolamide, N,N-dimethylformamide, N,N-dimethylacetamide, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monomethyl ether, lactic acid Butyl ester, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene glycol methyl ether, ethylene glycol ether, ethylene glycol-n-propyl ether, ethylene glycol-isopropyl ether, Ethylene glycol-n-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether , Diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diisobutyl ketone, isoamyl propionate, isoamyl isobutyrate, diiso Amyl ether, ethylene carbonate, propylene carbonate, etc. These can be used alone or in combination of two or more.

The solid content concentration in the liquid crystal alignment agent (the ratio of the total weight of the components other than the solvent of the liquid crystal alignment agent to the total weight of the liquid crystal alignment agent) is appropriately selected in consideration of viscosity, volatility, etc., and is preferably 1% by weight ~10% by weight. That is, as described below, the liquid crystal alignment agent is applied to the surface of the substrate, preferably by heating, thereby forming a coating film that is a liquid crystal alignment film or a coating film that becomes a liquid crystal alignment film. At this time, when the solid content concentration is less than 1% by weight, the film thickness of the coating film becomes too small, making it difficult to obtain a good liquid crystal alignment film. On the other hand, when the solid content concentration exceeds 10% by weight, the film thickness of the coating film becomes too large, making it difficult to obtain a good liquid crystal alignment film. In addition, the viscosity of the liquid crystal alignment agent increases and the coating property tends to decrease . The temperature when preparing the liquid crystal alignment agent is preferably 10°C to 50°C, and more preferably 20°C to 30°C.

<Liquid crystal element> The liquid crystal alignment film can be manufactured by using the liquid crystal alignment agent described above. In addition, the liquid crystal element of the present disclosure includes a liquid crystal alignment film formed using the liquid crystal alignment agent. The operation mode of the liquid crystal element is not particularly limited, for example, it can be applied to TN (Twisted Nematic) type, STN (Super Twisted Nematic) type, vertical alignment (Vertical Alignment, VA) type (including vertical alignment-multi-domain vertical alignment (Vertical Alignment) -Multi-domain Vertical Alignment (VA-MVA) type, vertical alignment-Vertical Alignment-Patterned Vertical Alignment (VA-PVA) type, etc.), IPS (In-Plane Switching) type, FFS (fringe field switching) Type, optically compensated bending (Optically Compensated Bend, OCB) type and other operating modes. In terms of maximizing the effects of using the liquid crystal alignment agent of the present disclosure, it can be preferably applied to so-called horizontal alignment type liquid crystal elements such as TN type, STN type, IPS type, and FFS type.

The liquid crystal element can be manufactured by a method including the following steps 1 to 3, for example. Step 1 uses different substrates according to the required operation mode. Steps 2 and 3 are common to all modes of operation. [Step 1: Formation of coating film] First, a liquid crystal alignment agent is coated on the substrate, and a coating film is formed on the substrate. When manufacturing, for example, a TN-type, STN-type, or VA-type liquid crystal element, first, two substrates provided with a patterned transparent conductive film are used as a pair, and on each transparent conductive film forming surface, it is preferably The liquid crystal alignment agent is separately applied by an offset printing method, a spin coating method, a roll coater method, or an inkjet printing method. As the substrate, for example, glass such as float glass and soda glass; including polyethylene terephthalate, polybutylene terephthalate, polyether ash, and polycarbonate can be used , Poly (alicyclic olefin) and other plastic transparent substrates. As the transparent conductive film provided on one side of the substrate, a Nessah (NESA) film (registered trademark of PPG Corporation) containing tin oxide (SnO ₂ ) and indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ) can be used. ITO film, etc. In the case of manufacturing an IPS-type or FFS-type liquid crystal element, the electrode-forming surface of a substrate provided with electrodes including a transparent conductive film or metal film patterned into a comb-teeth type, and a counter substrate not provided with electrodes On one side, the liquid crystal alignment agent is applied separately to form a coating film. As the metal film, for example, a film containing metal such as chromium can be used.

After the liquid crystal alignment agent is applied to form a coating film, for the purpose of preventing sagging of the applied liquid crystal alignment agent and the like, it is preferable to perform preheating (prebaking). The pre-baking temperature is preferably 30°C to 200°C, and the pre-baking time is preferably 0.25 minutes to 10 minutes. Then, the solvent is completely removed, and if necessary, a calcination (post-baking) step is performed for the purpose of thermally imidizing the amide acid structure present in the polymer. The calcination temperature (post-baking temperature) at this time is preferably 80°C to 300°C, and the post-baking time is preferably 5 minutes to 200 minutes. In this way, the film thickness of the formed film is preferably 0.001 μm to 1 μm, and more preferably 0.005 μm to 0.5 μm. After the liquid crystal alignment agent is applied on the substrate, the organic solvent is removed to form a liquid crystal alignment film or an organic coating film that becomes a liquid crystal alignment film.

[Step 2: Alignment ability-imparting treatment] In the case of manufacturing a TN-type, STN-type, IPS-type, or FFS-type liquid crystal element, the coating film formed in the above step 1 is subjected to a treatment for imparting liquid-crystal aligning ability. Thereby, the alignment ability of liquid crystal molecules is imparted to the coating film to become a liquid crystal alignment film. Examples of the alignment ability-imparting treatment include rubbing treatment of the coating film in a fixed direction by using a roll wound with a cloth containing fibers such as nylon, rayon, and cotton; and irradiating the coating film with polarized or unpolarized radiation Optical alignment processing, etc. In particular, the coating film formed using the liquid crystal alignment agent of the present disclosure has high photosensitivity and can exhibit good liquid crystal alignment even with a small amount of exposure, so the photo alignment method can be preferably applied. On the other hand, in the case of manufacturing a VA-type liquid crystal display element, the coating film formed in the above step 1 may be used directly as a liquid crystal alignment film, but the coating film may be subjected to an alignment ability-imparting treatment.

The light irradiation in the photo-alignment process can be performed by the following methods: [1] a method of irradiating the coating film after the post-baking step; [2] a coating film after the pre-baking step and before the post-baking step Irradiation method; [3] In at least any one of the pre-baking step and the post-baking step, a method of irradiating the coating film during heating of the coating film, etc. In the light alignment process, as the radiation irradiating the coating film, for example, ultraviolet rays and visible rays including light having a wavelength of 150 nm to 800 nm can be used. It is preferably ultraviolet light including light having a wavelength of 200 nm to 400 nm. When the radiation is polarized light, it may be linearly polarized light or partially polarized light. In addition, when the radiation used is linearly polarized light or partially polarized light, the substrate surface may be irradiated from the vertical direction, the substrate surface may be irradiated from the oblique direction, or these may be combined. In the case of irradiating unpolarized radiation, the direction of irradiation is an oblique direction.

As the light source used, for example, a mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, an excimer laser, or the like can be used. The radiation dose is preferably 400 J/m ² to 50,000 J/m ² , and more preferably 10,000 J/m ² to 20,000 J/m ² . In the case of using a conventionally known liquid crystal alignment film material for light alignment, a light exposure amount of 5,000 J/m ² or more is generally required, but according to the liquid crystal alignment agent of the present disclosure, even when the light exposure amount is set to less than 5,000 When J/m ² , preferably 3,000 J/m ² or less, good liquid crystal alignment can also be imparted. Therefore, it contributes to improving the productivity of the liquid crystal element and reducing manufacturing costs. In order to improve the reactivity, the coating film may be irradiated with light while being heated. The temperature during heating is usually 30°C to 250°C.

[Step (3): Construction of liquid crystal cell] The liquid crystal cell is manufactured by preparing two substrates on which the liquid crystal alignment film is formed as described above, and arranging the liquid crystal between the two substrates arranged oppositely. As a method of manufacturing a liquid crystal cell, for example, (1) such that each liquid crystal alignment film faces each other, two substrates are opposed to each other via a gap (cell gap), and the peripheral portions of the two substrates are attached using a sealant After the liquid crystal is injected into the surface of the substrate and the cell gap defined by the sealant, the injection hole is sealed; (2) On a predetermined part of one of the two substrates, for example, UV curable Sealant, and then dropping liquid crystal on a predetermined number of positions on the surface of the liquid crystal alignment film, then sticking another substrate with the liquid crystal alignment film facing, and spreading the liquid crystal on the entire surface of the substrate, and then sealing Method of curing agent, etc.

As the sealant, for example, an epoxy resin containing a hardener and alumina balls as spacers can be used. Examples of the liquid crystal include nematic liquid crystal and smectic liquid crystal. Among them, nematic liquid crystal is preferred. For example, Schiff base liquid crystal and azoxy can be used. Liquid crystal, biphenyl liquid crystal, phenylcyclohexane liquid crystal, ester liquid crystal, terphenyl liquid crystal, biphenyl cyclohexane liquid crystal, pyrimidine liquid crystal, dioxane liquid crystal, bicyclooctane It is liquid crystal, cubane liquid crystal, etc. In addition, cholesteric liquid crystal (cholesteric liquid crystal), chiral agent, ferroelectric liquid crystal (ferroelectric liquid crystal), etc. may be added to these liquid crystals and used.

Next, by attaching a polarizing plate to the outer surface of the liquid crystal cell as necessary, a liquid crystal element can be obtained. Examples of the polarizing plate include a polarizing plate formed by sandwiching a polarizing film called “H film” with a cellulose acetate protective film, or a polarizing plate including the H film itself. A film formed by aligning one side of vinyl alcohol to absorb iodine.

The liquid crystal element of the present disclosure can be effectively applied to various devices, for example, it can be used in: televisions, clocks, portable game consoles, word processors, note type personal computers, car navigation Various displays such as car navigation system, camcorder, personal digital assistant (PDA), digital camera, mobile phone, smart phone, information display, various monitors, etc. Device, or dimming film, etc. In addition, a liquid crystal element formed using the liquid crystal alignment agent of the present disclosure can also be applied to a retardation film. [Example]

Hereinafter, the present invention will be further specifically described by examples, but the present invention is not limited by these examples.

In the following examples, the weight average molecular weight of each polymer and the solution viscosity of each polymer solution were measured by the following method. In the following examples, the "compound represented by formula (X)" may be abbreviated as "compound (X)". [Weight average molecular weight of polymer] The weight average molecular weight Mw of the polymer is a polystyrene conversion value measured by gel permeation chromatography under the following conditions. Column: manufactured by Tosoh (shares), TSK gel (TSKgel) GRCXLII Solvent: tetrahydrofuran, or lithium bromide and N,N-dimethylformamide solution containing phosphoric acid Temperature: 40℃ Pressure: 68 kgf/ cm ² [Solution viscosity of polymer solution] The solution viscosity of polymer solution [mPa·s] is prepared by using the E-type rotary viscometer to prepare a solution with a polymer concentration of 20% by weight using a specified solvent at 25°C Under the measurement.

流程1<Synthesis of Compounds> In the following synthesis examples, the necessary amount in the synthesis of the polymer afterwards is ensured by repeating the following ratio as necessary. [Synthesis Example 1] Compound (2-1) was synthesized according to the following scheme 1. [化10]

Process 1

· Synthesis of Compound (2-1A) To a 1000 mL quartz flask equipped with a 100 W high-pressure mercury lamp and a cooling tube, 800 mL of acetone, 20 mL of 12N hydrochloric acid water, and 32.6 g of 4-aminocinnamic acid were irradiated to 2.7 mW/ UV light of cm ² for 40 hours. After the reaction was completed, filtration and drying were performed to obtain 30 g of compound (2-1A). · Synthesis of Compound (2-1B) To a 200 mL eggplant-shaped flask equipped with a reflux tube and a nitrogen introduction tube, 20.0 g of Compound (2-1A), 100 mL of thionyl chloride and N,N-dimethyl were added 1 mL of formamide was refluxed for 1 hour. After completion of the reaction, after concentration and drying, recrystallization with tetrahydrofuran, filtration and drying were performed to obtain 17.4 g of compound (2-1B). -Synthesis of Compound (2-1C) To a 300 mL three-necked flask equipped with a dropping funnel, nitrogen introduction tube, and thermometer, 17.4 g of Compound (2-1B) and 200 mL of toluene were added, and cooled to 5°C or lower. Secondly, after slowly adding a solution of 3M butyl peroxide in 5M decane, 3.2 mL of pyridine was slowly added dropwise. After the reaction was completed, 5% hydrochloric acid water was added, the water layer was removed, 5% potassium hydroxide aqueous solution was added, the water layer was removed, and the organic layer was washed with water three times, dried with magnesium sulfate, and Concentrate and dry. Then, it recrystallized with the mixed solvent of ethyl acetate and hexane, it filtered and dried, and 15.1 g of compound (2-1C) was obtained. ·Synthesis of Compound (2-1) To a 1 L three-necked flask equipped with a reflux tube, nitrogen introduction tube and thermometer, 15.1 g of Compound (2-1C) and 500 mL of isopropyl toluene (cymene) were added at 150°C React for 12 hours. After the reaction, it was concentrated to 150 mL and reprecipitated in 1500 mL of methanol. After filtering the resulting precipitate, the precipitate was dissolved in tetrahydrofuran, purified by a silica column (developing solvent: chloroform/ethanol=90/10 (weight ratio)), and the concentrated and precipitated crystals were filtered And drying to obtain 4.6 g of compound (2-1).

流程2[Synthesis Example 2] The compound (2-2) was synthesized according to the following scheme 2. [Chem 11]

Process 2

To a 200 mL eggplant-shaped flask equipped with a nitrogen introduction tube, 4.76 g of compound (2-1), 50 mL of acetonitrile, 10.91 g of tert-butyl dicarbonate and 2.93 g of N,N-dimethylaminopyridine were added, Stir at room temperature for 5 hours. After the reaction was completed, 200 mL of ethyl acetate was added, and the liquid was washed three times with water, dried over magnesium sulfate, and the precipitate produced by concentration under reduced pressure was filtered and dried to obtain compound (2-2 ) 7.02 g.

流程3[Synthesis Example 3] Compound (2-3) was synthesized according to the following scheme 3. To a 300 mL three-necked flask equipped with a nitrogen introduction tube, a reflux tube, and a thermometer, 8.0 g of compound (2-1A) and 80 mL of concentrated sulfuric acid were added and reacted at 140° C. for 6 hours. After returning to room temperature, it was poured into 1 L of diethyl ether and the deposited precipitate was recovered by filtration, dispersed in 200 mL of tetrahydrofuran, and subjected to 2 liquid separation washings with a 1 M potassium hydroxide aqueous solution. Next, 200 mL of ethyl acetate was added to the organic layer and washed three times with water, then concentrated and dried, recrystallized with dimethylacetamide, filtered, and dried to obtain a compound ( 2-3) 4.6 g. [化12]

Process 3

[Synthesis Example 3A (Other method of compound (2-3))] To a 200 mL three-necked flask equipped with a nitrogen introduction tube, a reflux tube, and a thermometer, 80 mL of 30% fuming sulfuric acid was added, and cooled to 5° C. or less in an ice bath. Next, 4.0 g of compound (2-1A) was added, the temperature was raised to 50°C, and the reaction was carried out for 2 hours. After the reaction was completed, the precipitate produced by pouring the reaction solution into 1 L of ice water was recovered by filtration. Next, the precipitate was suspended in 1 L of a 1M sodium hydroxide aqueous solution, and the precipitate was recovered by filtration, washed with water, and dried in vacuum, thereby obtaining a white powder. Next, the powder was recrystallized with N,N-dimethylacetamide, filtered, and vacuum dried, thereby obtaining 2.3 g of compound (2-3).

流程4[Synthesis Example 4] Compound (2-5) was synthesized according to the following scheme 4. In addition, the mixture of the compound (2-5) and the compound (2-6) is obtained in the following scheme 4, and the mixture obtained in the following scheme 4 is used as the compound (2-5) in the following polymerization example. [Chem 13]

Process 4

· Synthesis of Compound (2-5A) To a 1000 mL quartz flask equipped with a 100 W high-pressure mercury lamp and a cooling tube, 300 mL of benzene, 20 mL of 12N hydrochloric acid water, 116 g of indene and 10 g of benzophenone were irradiated for 2.7 mW/cm ² of ultraviolet light for 40 hours. After completion of the reaction, concentration under reduced pressure was performed to obtain a crude purified product of the oily compound (2-5A). After purifying the oily substance with a silicon dioxide column (developing solvent: hexane), it was recrystallized with acetone, filtered, and dried to obtain 70 g of compound (2-5A). ·Synthesis of Compound (2-5B) In a 1000 mL three-necked flask equipped with a nitrogen introduction tube and a thermometer, 70 g of Compound (2-5A) and 160 mL of concentrated sulfuric acid were added, and cooled to 5°C or less in an ice bath. Next, while maintaining the temperature below 10°C, 49.2 mL of concentrated sulfuric acid and concentrated nitric acid were slowly added. Next, after adding 540 g of ice, returning to room temperature and filtering, washing the precipitate with ethanol, and purifying the precipitate using a silica column (developing solvent: chloroform: ethanol=9:10), Thus, 48.3 g of compound (2-5B) was obtained. · Synthesis of Compound (2-5) To a 1000 mL three-necked flask equipped with a nitrogen introduction tube, a reflux tube, and a thermometer, 48.3 g of Compound (2-5B), 500 mL of tetrahydrofuran, 250 mL of ethanol, and 2.4 g of 5% palladium carbon were added After that, 65 mL of hydrazine monohydrate was slowly added and reacted at 65°C for 2 hours. After the reaction is completed, the filtrate obtained by filtration is concentrated under reduced pressure, and then purified using a silica column (developing solvent: chloroform: ethanol=7:3), concentrated and dried, and dried. 26.2 g of compound (2-5) was obtained.

流程5   ·化合物（2-9A）的合成 向具備回流管、溫度計及氮氣導入管的300 mL的三口燒瓶中添加甲基環己烷96 g、金屬鉀2 g及β-甲基二苯乙烯24 g，在100℃下反應3小時。反應結束後，進行蒸餾純化，由此而獲得化合物（2-9A）10.6 g。 ·化合物（2-9B）的合成 向具備回流管、溫度計及氮氣導入管的100 mL的三口燒瓶中加入化合物（2-9A）10.6 g、硝酸24.6 g，在80℃下反應6小時。反應結束後，對注入至300 mL的冰水中所析出的沉澱進行過濾，以水進行洗滌後，以乙醇進行再結晶，由此而獲得化合物（2-9B）13.95 g。 ·化合物（2-9）的合成 向具備回流管、溫度計及氮氣導入管的300 mL的三口燒瓶中加入化合物（2-9B）13.95 g、5%鈀碳0.70 g、四氫呋喃100 mL、乙醇100 mL及肼一水合物8.3 g，在70℃下反應1小時。反應結束後，將進行矽藻土過濾所獲得的濾液減壓濃縮至50 mL，加入乙酸乙酯200 mL，以水進行三次分液洗滌後，對減壓濃縮而析出的結晶進行過濾，並進行真空乾燥，由此而獲得化合物（2-9）10.3 g。[Synthesis Example 5] Compound (2-9) was synthesized according to the following scheme 5. [化14]

Process 5 · Synthesis of Compound (2-9A) To a 300 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen introduction tube, 96 g of methylcyclohexane, 2 g of potassium metal, and β-methylstilbene 24 were added g, react at 100°C for 3 hours. After the reaction was completed, distillation and purification were performed to obtain 10.6 g of compound (2-9A). · Synthesis of Compound (2-9B) To a 100 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen introduction tube, 10.6 g of Compound (2-9A) and 24.6 g of nitric acid were added and reacted at 80°C for 6 hours. After the reaction was completed, the precipitate deposited in 300 mL of ice water was filtered, washed with water, and recrystallized with ethanol to obtain 13.95 g of compound (2-9B). ·Synthesis of Compound (2-9) To a 300 mL three-necked flask equipped with a reflux tube, thermometer, and nitrogen introduction tube, compound (2-9B) 13.95 g, 5% palladium-carbon 0.70 g, tetrahydrofuran 100 mL, and ethanol 100 mL And hydrazine monohydrate 8.3 g, react at 70 ℃ for 1 hour. After the reaction was completed, the filtrate obtained by filtration through diatomaceous earth was concentrated to 50 mL under reduced pressure, 200 mL of ethyl acetate was added, and the liquid was washed three times with water, and then the crystals precipitated under reduced pressure were filtered and filtered. Vacuum drying, and 10.3 g of compounds (2-9) were obtained.

流程6[Synthesis Example 6] The compound (A-1EC) was synthesized according to the following scheme 6. [化15]

Process 6

·Synthesis of Compound (A-1E) To a 200 mL three-necked flask equipped with a reflux tube, a nitrogen introduction tube, and a thermometer, 27.0 g of Compound (A-1), 80 mL of methanol, and 0.99 g of pyridine were added and reacted at 65°C for 10 hour. After the reaction was completed, after concentration to 100 mL under reduced pressure, the crystals precipitated by adding 200 mL of ethyl acetate and concentrating to 50 mL were filtered and dried to obtain 27.8 g of compound (A-1E).

·Synthesis of compound (A-1EC) To a 300 mL three-necked flask equipped with a reflux tube and a nitrogen introduction tube, 27.8 g of compound (A-1E), 150 mL of thionyl chloride and N,N-dimethylformamide were added 0.1 mL of amine was refluxed for 1 hour. After the reaction was completed, it was concentrated and dried under reduced pressure, and then recrystallized with cyclohexane, filtered, and dried to obtain 26.0 g of a compound (A-1EC).

流程7[Synthesis Example 7] Compound (2-10) was synthesized according to the following scheme 7. [Chem 16]

Process 7

To a 200 mL eggplant-shaped flask equipped with a nitrogen introduction tube, 5.80 g of compound (2-3), 50 mL of dimethyl sulfoxide, 10.91 g of third butyl dicarbonate, and N,N-dimethylamino group were added 2.93 g of pyridine was stirred at room temperature for 5 hours. After the reaction was completed, 200 mL of ethyl acetate was added, and the liquid was washed three times with water, dried over magnesium sulfate, and the precipitate produced by concentration under reduced pressure was filtered and dried to obtain a compound (2-10 ) 8.55 g.

<Synthesis of Polymer> [Polymerization Example 1] 10.56 g of compound (A-1) as tetracarboxylic dianhydride and 10.56 g of compound (2-1) obtained in Synthesis Example 1 as diamine were dissolved In N-methyl-2-pyrrolidone (N-methyl-2-pyrrolidone, NMP) 80 g, the reaction was carried out at room temperature for 4 hours, thereby obtaining 20% by weight containing polyamic acid (PAA-1) The solution. The solution viscosity of the solution was 2,000 mPa·s. [化17]

[Polymerization Example 2] 8.77 g of compound (A-2) as tetracarboxylic dianhydride and 11.23 g of compound (2-1) obtained in Synthesis Example 1 as diamine were dissolved in N-methyl- In 80 g of 2-pyrrolidone, the reaction was carried out at room temperature for 4 hours, thereby obtaining a solution containing 20% by weight of polyamic acid (PAA-2). The solution viscosity of the solution was 2,400 mPa·s. [Chemical 18]

[Polymerization Example 3] 12.57 g of compound (A-3) as tetracarboxylic dianhydride and 7.43 g of compound (2-1) obtained in Synthesis Example 1 as diamine were dissolved in N-methyl- In 80 g of 2-pyrrolidone, a reaction was carried out at room temperature for 4 hours, thereby obtaining a solution containing 20% by weight of polyamic acid (PAA-3). The solution viscosity of the solution was 2,700 mPa·s. [Chem 19]

[Polymerization Example 4] To a 100 mL three-necked flask equipped with a dropping funnel, a thermometer, and a nitrogen introduction tube, 4.38 g of compound (2-2), 20 mL of tetrahydrofuran, and a 1M potassium hexamethyldisilazane tetrahydrofuran solution 11 were added mL, cooled to below 5°C in an ice bath. Next, a solution obtained by dissolving 2.09 g of cyclohexane-1,4-dicarboxylic acid dichloride in 20 mL of tetrahydrofuran was added dropwise over 30 minutes, and then returned to room temperature and stirred for a whole day and night. After the reaction was completed, the precipitate precipitated by pouring the reaction solution into 400 mL of water was filtered, washed with water and methanol, and then vacuum-dried to obtain 5.0 g of polyamidoamine (PA-1). The weight average molecular weight of the obtained polyamide (PA-1) was 12,000. [化20]

[Polymerization Example 5] 8.5 g of compound (A-1) as tetracarboxylic dianhydride and 11.5 g of compound (2-3) obtained in Synthesis Example 3 as diamine were dissolved in N-methyl- In 80 g of 2-pyrrolidone (NMP), a reaction was carried out at room temperature for 4 hours, thereby obtaining a solution containing 20% by weight of polyamic acid (PAA-4). The solution viscosity of the solution was 1,800 mPa·s. [Polymerization Example 6] 11.0 g of the compound (A-1) as tetracarboxylic dianhydride and 11.0 g of the compound (2-5) obtained in Synthesis Example 4 as diamine were dissolved in N-methyl- In 80 g of 2-pyrrolidone (NMP), the reaction was carried out at room temperature for 4 hours, thereby obtaining a solution containing 20% by weight of polyamic acid (PAA-5). The solution viscosity of the solution was 1,900 mPa·s.

[Polymerization Example 7] Dissolve 8.9 g of compound (A-1) as tetracarboxylic dianhydride and 11.1 g of compound (2-9) obtained in Synthesis Example 5 as diamine in N-methyl- In 80 g of 2-pyrrolidone (NMP), a reaction was carried out at room temperature for 4 hours, thereby obtaining a solution containing 20% by weight of polyamic acid (PAA-6). The solution viscosity of the solution was 2,300 mPa·s. [Polymerization Example 8] 11.6 g of compound (A-3) as tetracarboxylic dianhydride and 8.4 g of compound (2-3) obtained in Synthesis Example 3A as diamine were dissolved in N-methyl- In 80 g of 2-pyrrolidone (NMP), the reaction was carried out at room temperature for 4 hours, thereby obtaining a solution containing 20% by weight of polyamic acid (PAA-7). The solution viscosity of the solution was 2,100 mPa·s. [Polymerization Example 9] In a 100 mL eggplant-shaped flask equipped with a nitrogen introduction tube, 4.1 g of compound (2-3), 4.6 g of compound (A-1EC), 2.7 g of pyridine, and 18.2 of N-methyl-2-pyrrolidone 54.6 g of g and γ-butyrolactone (γ-BL) were polymerized at room temperature for 3 hours. Next, the precipitate generated by pouring into 500 mL of water was recovered by filtration, washed with water and isopropanol, and vacuum-dried to obtain 6.4 g of polyamide (PAE-1).

[Polymerization Example 10] To a 100 mL three-necked flask equipped with a dropping funnel, a thermometer and a nitrogen introduction tube, 4.91 g of the compound (2-10) obtained in Synthesis Example 7 above, 20 mL of tetrahydrofuran and 1M hexamethyl were added 11 mL of potassium disilazane tetrahydrofuran solution, cooled to below 5°C in an ice bath. Next, a solution obtained by dissolving 1.05 g of cyclohexane-1,4-dicarboxylic acid dichloride and 1.70 g of compound (C-1) in 20 mL of tetrahydrofuran was added dropwise over 30 minutes, and then returned to room temperature. Stir all day and night. After the reaction was completed, the precipitate deposited by pouring the reaction solution into 400 mL of water was filtered, washed with water and methanol, and then vacuum-dried to obtain 5.2 g of polyamidoamine (PA-2). The weight average molecular weight of the obtained polyamide (PA-2) was 10,000. [化21]

[Polymerization Example 11] 9.3 g of the compound (A-2) as tetracarboxylic dianhydride and 10.7 g of 2,2′-dimethyl-4,4′-diaminobiphenyl as diamine were dissolved in In 80 g of N-methyl-2-pyrrolidone (NMP), a reaction was carried out at room temperature for 4 hours, thereby obtaining a solution containing 20% by weight of polyamic acid (PAA-8). The solution viscosity of the solution was 2,500 mPa·s.

[Comparative Polymerization Example 1] 9.35 g of the compound (A-2) as tetracarboxylic dianhydride and 10.65 g of the compound (D-1) as diamine were dissolved in 80 g of N-methyl-2-pyrrolidone, The reaction was carried out at room temperature for 4 hours, thereby obtaining a solution containing 20% by weight of polyamic acid (RPA-1). The solution viscosity of the polymer solution was 2,500 mPa·s. [化22]

<Preparation and evaluation of liquid crystal alignment agent> [Example 1] 1. Preparation of liquid crystal alignment agent To a solution containing the polyamic acid (PAA-1) obtained in the polymerization example 1, N-methyl-2 was added -Pyrrolidone (NMP) and butyl cellosolve (BC), fully stirred to prepare a solution with a solvent composition of NMP: BC=50:50 (weight ratio) and a solid content concentration of 2.5% by weight. The solution was filtered using a filter with a pore size of 1 μm, thereby preparing a liquid crystal alignment agent.

2. Evaluation of liquid crystal alignment agent (1) Production of liquid crystal cell for evaluation of liquid crystal alignment, voltage retention ratio and contrast 1 Using a spin coater and applying a film thickness of 0.1 μm, the liquid crystal alignment agent prepared above was applied After each transparent electrode surface of two glass substrates (a pair) having a transparent electrode containing an ITO film, it was heated (pre-baked) at 80° C. for 1 minute. Then, after heating (post-baking) in a clean oven at 230°C for 1 hour, the surface of each coating film was irradiated with a bright line containing 254 nm from the normal direction of the substrate at an irradiation dose of 1,000 mJ/cm ² using an Hg-Xe lamp. After the polarized ultraviolet rays were further heated (post-baking) in a clean oven at 230° C. for 30 minutes, liquid crystal alignment films were formed on the two (pair) substrates, respectively. Next, for one substrate of the pair of substrates, a liquid crystal injection port was left, and an epoxy resin adhesive with an alumina ball with a diameter of 5.5 μm was applied to the surface where the liquid crystal alignment film was formed by screen printing. After the outer peripheral portion, a pair of substrates are overlapped and pressure-bonded so that the formation surface of the liquid crystal alignment film faces and the projection direction of the polarized surface toward the substrate surface coincides with light irradiation, and the adhesive is heated at 150°C for 1 hour Heat hardened. Then, after filling nematic liquid crystal (made by Merck, MLC-7028) between the pair of substrates from the liquid crystal injection port, the liquid crystal injection port was sealed with an epoxy-based adhesive. Furthermore, in order to remove the flow alignment at the time of liquid crystal injection, it was heated to 150° C. and then slowly cooled to room temperature, thereby manufacturing a liquid crystal cell (referred to as “liquid crystal cell A”). (2) Manufacture of liquid crystal cells for evaluation of liquid crystal alignment, voltage retention, and contrast 2 Change the irradiation amount of polarized ultraviolet light in the light alignment step to 300 mJ/cm ² , in addition to, "2. (1) The manufacture of liquid crystal cells for evaluation of liquid crystal alignment, voltage retention, and contrast 1" was similarly carried out (the liquid crystal cell is referred to as "liquid crystal cell B").

(3) Evaluation of Liquid Crystal Alignment For the two liquid crystal cells A and B manufactured above, the polarizing microscope was used to observe the abnormal area when the AC 5 V voltage was turned on and off (applied and released). Are there any. At this time, the case where no abnormal region was observed was evaluated as "good" for liquid crystal alignment, and the case where even one abnormal region was observed in the display region was evaluated as "poor" for liquid crystal alignment. As a result, liquid crystal cell A and liquid crystal cell B All of them were judged as "good" in liquid crystal alignment. (4) Evaluation of voltage retention rate After applying the voltage of 5 V for 60 microseconds to each of the two liquid crystal cells A and B manufactured above and applying the voltage at a span of 167 milliseconds, the measurement is made after the application is released. The voltage retention rate after 167 milliseconds. The voltage retention rate was 99.0% or more as "good", 98.0% or more and less than 99.0% as "acceptable", and less than 98.0% as "bad". As a result, both liquid crystal cell A and liquid crystal cell B were judged as The voltage retention rate is "good". In addition, a model name "VHR-1" manufactured by Toyo Technica Co., Ltd. was used as a voltage retention measurement device.

(5) Evaluation of contrast For the two liquid crystal cells A and B manufactured above, the contrast after driving for 30 hours was respectively found. The evaluation is carried out as follows. Using a device in which a polarizing element and an analyzer are provided between the light source and the light quantity detector, the liquid crystal cell manufactured above is arranged between the polarizing element and the analyzer, and the amount of light transmission β under crossed Nicols is ascertained. These values are substituted into the following equation (1) to calculate the minimum relative transmittance (%). Minimum relative transmittance (%)=(β-B0)/(B100-B0)×100 (1) (Equation (1), B0 is the amount of blank light transmission under crossed Nicols, B100 is parallel Nico Blank light transmittance under the ear, β is the light transmittance measured under the crossed Nicols with the liquid crystal cell disposed between the polarizing element and the analyzer) Calculated from the above equation (1) The minimum relative transmittance of represents the degree of black level in a dark state, and the smaller the value of the minimum relative transmittance, the more excellent the contrast can be evaluated. The case where the minimum relative transmittance was less than 0.5% was evaluated as "good" contrast, the case of 0.5% to 1.0% was evaluated as "acceptable", and the case of more than 1.0% was evaluated as "contrary". As a result, the liquid crystal cell Both A and liquid crystal cell B are judged to have a "good" contrast.

[Example 2 to Example 6 and Comparative Example 1] Instead of using a solution containing a polyamic acid (PAA-1) instead of a solution containing a polymer of the type shown in Table 1 below Example 1 A liquid crystal alignment agent was prepared in the same manner, and the liquid crystal cell was manufactured and subjected to various evaluations using the liquid crystal alignment agent. In addition, in Examples 5 and 6, as described in Table 1 below, the irradiation amount of polarized ultraviolet rays in the light alignment step in the manufacture of the liquid crystal cell was changed. The evaluation results are shown in Table 1 below.

[Table 1]

As understood from Table 1, it can be confirmed that the liquid crystal alignment film formed using the liquid crystal alignment agent containing the polymer [P] has high photosensitivity, and thus the liquid crystal cell provided with the liquid crystal alignment film exhibits excellent liquid crystal alignment In addition to the high voltage retention rate, the contrast characteristics are also excellent. In addition, in Examples 5 and 6 using the polymer [P] having a condensed ring in a specific partial structure, even in the case where light alignment treatment is performed with an irradiation amount less than 300 mJ/cm ² , It also shows good liquid crystal alignment, voltage retention and contrast characteristics.

[Example 7, Example 8] Using a solution containing polyamic acid (PAA-6) or polyamino acid (PAA-7), liquid crystal alignment agents were separately prepared in the same manner as in Example 1, and the liquid crystal alignment was used For the manufacture and various evaluations of liquid crystal cells. The results are shown in Table 2 below. [Example 9] Polyamide (PAE-1) was used, and the solvent composition of the liquid crystal alignment agent was NMP: γ-BL: BC=40: 40:20 (weight ratio), and the solid content concentration was 2.5% by weight The liquid crystal alignment agent was evaluated in the same manner as in Example 1 except that it was prepared in the same manner. The results are shown in Table 2. [Example 10] Other than using Polyamide (PA-2), the solvent composition of the liquid crystal alignment agent was NMP:BC=80:20 (weight ratio), and the solid content concentration was 2.5% by weight. In the same manner as in Example 1, the evaluation of the liquid crystal alignment agent was performed. The results are shown in Table 2.

[Table 2]

[Example 11] The polymer composition shown in the following Table 3 and the solvent composition of the liquid crystal alignment agent are NMP: γ-BL: BC=40: 40: 20 (weight ratio), and the solid content concentration becomes 2.5% by weight The liquid crystal alignment agent was evaluated in the same manner as in Example 1 except that it was prepared by the method. The results are shown in Table 3 below. [Example 12] It was prepared such that the polymer composition shown in Table 3 below and the solvent composition of the liquid crystal alignment agent became NMP: BC=80:20 (weight ratio), and the solid content concentration became 2.5% by weight, except Except for Example 1, the evaluation of the liquid crystal alignment agent was performed. The results are shown in Table 3 below.

[table 3]

It was also confirmed from Examples 7 to 12 that, according to the liquid crystal alignment agent containing the polymer [P], an organic film showing excellent liquid crystal alignment can be obtained with a small amount of exposure, and in addition, a high Liquid crystal cell with voltage retention and contrast characteristics.

no

no

Claims (7)

A liquid crystal alignment agent containing a polymer [P] having a partial structure represented by the following formula (1) in the main chain,

(In formula (1), R ¹ is a hydrogen atom, a fluorine atom, a C 1-3 alkyl group, a C 1-3 fluoroalkyl group, or -CO- which directly bonds with Ar ¹ to form a part of the ring Or a C1-C3 alkanediyl group, R ⁴ is a hydrogen atom, a fluorine atom, a C1-C3 alkyl group, a C1-C3 fluoroalkyl group or directly bonded to Ar ² to form a part of the ring -CO- or C1-C3 alkanediyl; R ² , R ³ , R ⁵ and R ⁶ are independently hydrogen atom, fluorine atom, C1-C3 alkyl group or C1-C3 Fluoroalkyl group; Ar ¹ and Ar ² are each independently a cyclic group having an aromatic ring or a heterocyclic ring or an ethynyl group, the cyclic group may also have a substituent in the ring part; "*" represents a bonding bond) . The liquid crystal alignment agent according to item 1 of the patent application range, wherein the polymer [P] is selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, polyamide, polyester and polyether At least one of the group formed. A liquid crystal alignment film is formed using the liquid crystal alignment agent as described in item 1 or item 2 of the patent application. A liquid crystal element comprising the liquid crystal alignment film as described in item 3 of the patent application. A method for manufacturing a liquid crystal alignment film, which applies a liquid crystal alignment agent as described in item 1 or 2 of a patent application to a substrate to form a coating film, and irradiates the coating film with radiation. A polymer selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, polyamide, polyester and polyether, and has the following formula (1) in the main chain ) Represents part of the structure,

(In formula (1), R ¹ is a hydrogen atom, a fluorine atom, a C 1-3 alkyl group, a C 1-3 fluoroalkyl group, or -CO- which directly bonds with Ar ¹ to form a part of the ring Or a C1-C3 alkanediyl group, R ⁴ is a hydrogen atom, a fluorine atom, a C1-C3 alkyl group, a C1-C3 fluoroalkyl group or directly bonded to Ar ² to form a part of the ring -CO- or C1-C3 alkanediyl; R ² , R ³ , R ⁵ and R ⁶ are independently hydrogen atom, fluorine atom, C1-C3 alkyl group or C1-C3 Fluoroalkyl group; Ar ¹ and Ar ² are each independently a cyclic group having an aromatic ring or a heterocyclic ring or an ethynyl group, the cyclic group may also have a substituent in the ring part; "*" represents a bonding bond) . A diamine, which is represented by the following formula (2A),

(In formula (2A), R ¹ is a hydrogen atom, a fluorine atom, a C 1-3 alkyl group, a C 1-3 fluoroalkyl group, or -CO- which directly bonds with Ar ¹ to form a part of the ring Or a C1-C3 alkanediyl group, R ⁴ is a hydrogen atom, a fluorine atom, a C1-C3 alkyl group, a C1-C3 fluoroalkyl group or directly bonded to Ar ² to form a part of the ring -CO- or C1-C3 alkanediyl; R ² , R ³ , R ⁵ and R ⁶ are independently hydrogen atom, fluorine atom, C1-C3 alkyl group or C1-C3 Fluoroalkyl group; Ar ¹ and Ar ² are each independently a cyclic group having an aromatic ring or a heterocyclic ring or an ethynyl group, the cyclic group may also have a substituent in the ring portion; X ¹ and X ² are independently Ground is a single bond or a divalent linking group).