Liquid crystal alignment agent, liquid crystal alignment film, liquid crystal element and polymer

Abstract

To provide a liquid crystal aligning agent which allows for producing a liquid crystal alignment film that is highly reliable even when used under harsh conditions and offers superior narrow-line adhesion.SOLUTION: A liquid crystal aligning agent provided herein contains a polymer (P) having a partial structure represented by a formula (1) below. In the formula, R1 and R2 independently represent a hydrogen atom or alkyl group having 1-3 carbon atoms. X1 represents a single bond, alkanediyl group having 1-6 carbon atoms, -O-, -CH2-O-*1, -O-(CH2)a-O-, -(CH2)b-COO-*1, -(CH2)b-COO-(CH2)a-O-*1, or -O-CO-*1. (a) represents an integer of 1 to 6. (b) represents an integer of 0 to 6.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a liquid crystal alignment agent, a liquid crystal alignment film, and a liquid crystal element. and polymerization On the body Regarding. [Background technology]

[0002] Liquid crystal elements are used in a wide range of applications, from large display devices such as liquid crystal televisions and information displays to small display devices such as smartphones and tablet PCs. As these applications become more diverse, high display quality is required of liquid crystal elements, and efforts are being made to improve the various properties of liquid crystal alignment films as one way to further improve the quality of liquid crystal elements (see, for example, Patent Document 1).

[0003] Patent Document 1 discloses the production of polyamic acid and polyimide using a diamine having an acetophenone structure and a vertical alignment structure in the molecule, and the production of a liquid crystal alignment film using a liquid crystal alignment agent containing the produced polyimide. As a result, the device described in Patent Document 1 is designed to exhibit a tilt angle of 85 to 89.5° required for the PSA system and the VA system by irradiation with a long wavelength of 365 nm.

[0004] In display devices for mobile applications, such as smartphones and tablet PCs, efforts are being made to narrow the frame in order to achieve both a larger operating area for the touch panel and a smaller display device. One known method for narrowing the frame is to form a liquid crystal alignment film over the entire surface of the substrate, and then apply a sealant to the liquid crystal alignment film and bond the substrates together (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2017 / 030170 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-109154 Summary of the Invention [Problem to be solved by the invention]

[0006] As liquid crystal devices become more versatile, they are expected to be used in harsher environments than ever before. Liquid crystal devices are required to maintain their performance even when used under harsh conditions. Specifically, they must be reliable enough to withstand long-term use in high-temperature environments, and highly reliable in terms of resistance to high temperatures and humidity.

[0007] When a sealant is placed on a liquid crystal alignment film for the purpose of narrowing the frame of a liquid crystal element, the liquid crystal alignment film tends to peel off from the substrate at the sealant portion. In particular, in recent years, narrowing the width of the sealant (hereinafter also referred to as "seal width") has been considered in order to further narrow the frame. Even when substrates are bonded together with a narrow seal width, the liquid crystal alignment film is required to have a property where it is less likely to peel off from the substrate at the sealant portion (hereinafter also referred to as "narrow line adhesion").

[0008] The present invention has been made in consideration of the above circumstances, and its main object is to provide a liquid crystal aligning agent that is highly reliable even when used under harsh conditions and that can provide a liquid crystal alignment film with excellent narrow line adhesion. [Means for solving the problem]

[0009] In order to solve the above problems, the present inventors have focused on introducing a specific chromanone structure into a polymer. Specifically, the present invention employs the following means to solve the above problems.

[0010] [1] A liquid crystal aligning agent containing a polymer (P) having a partial structure represented by the following formula (1): [ka] (In formula (1), R 1 and R 2are each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. 1 represents a single bond, an alkanediyl group having 1 to 6 carbon atoms, -O-, -CH2-O-* 1 , -O-(CH2) a -O-, -(CH2) b -COO-* 1 , -(CH2) b -COO-(CH2) a -O-* 1 or -O-CO-* 1 a is an integer between 1 and 6. b is an integer between 0 and 6. * 1 " represents a bond to the benzene ring in formula (1). "*" represents a bond.)

[0011] [2] A liquid crystal alignment film formed using the liquid crystal alignment agent described above in [1]. [3] A liquid crystal element comprising the liquid crystal alignment film of [2] above. [4] A method for manufacturing a liquid crystal element, comprising: a step of applying the liquid crystal aligning agent according to [1] above onto each conductive film of a pair of substrates having a conductive film to form a coating film; a step of constructing a liquid crystal cell by disposing the pair of substrates on which the coating films have been formed so that the coating films face each other via a liquid crystal layer; and a step of irradiating the liquid crystal cell with light while applying a voltage between the conductive films. [5] A polymer having a partial structure represented by the above formula (1).

[0012] [6] A diamine represented by the following formula (2-1): [ka] (In formula (2-1), R 1 and R 2 are each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. 1 represents a single bond, an alkanediyl group having 1 to 6 carbon atoms, -O-, -CH2-O-* 1 , -O-(CH2) a -O-, -(CH2) b -COO-* 1 , -(CH2) b -COO-(CH2) a-O-* 1 or -O-CO-* 1 a is an integer between 1 and 6. b is an integer between 0 and 6. * 1 " represents a bond to the benzene ring in formula (2-1). 1 is a trivalent aromatic ring group.

[0013] [7] A diamine represented by the following formula (2-2): [ka] (In formula (2-2), R 1 and R 2 are each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. 1 represents a single bond, an alkanediyl group having 1 to 6 carbon atoms, -O-, -CH2-O-* 1 , -O-(CH2) a -O-, -(CH2) b -COO-* 1 , -(CH2) b -COO-(CH2) a -O-* 1 or -O-CO-* 1 a is an integer between 1 and 6. b is an integer between 0 and 6. * 1 " represents a bond to the benzene ring in formula (2-2). 2 and Ar 4 are each independently a divalent aromatic ring group. 3 is a trivalent aromatic ring group. 2 and X 3 are each independently a single bond, -O-, -CH2-, -CO-, or -NR 3 -, -COO-, -OCO-, -CONR 3 -or-NR 3 CO-. R 3 is a hydrogen atom or a monovalent organic group. [Effects of the Invention]

[0014] A liquid crystal aligning agent containing the polymer (P) can provide a liquid crystal alignment film that is highly reliable even when used under severe conditions and has excellent narrow line adhesion. DETAILED DESCRIPTION OF THE INVENTION

[0015] Matters related to the embodiments of the present disclosure will be described in detail below. In this specification, the term "hydrocarbon group" includes chain hydrocarbon groups, alicyclic hydrocarbon groups, and aromatic hydrocarbon groups. The term "chain hydrocarbon group" refers to a linear hydrocarbon group or a branched hydrocarbon group that does not contain a cyclic structure and is composed solely of a chain structure. However, the group may be saturated or unsaturated. The term "alicyclic hydrocarbon group" refers to a hydrocarbon group that contains only an alicyclic hydrocarbon structure as a ring structure and does not contain an aromatic ring structure. However, the group does not necessarily have to be composed solely of an alicyclic hydrocarbon structure, and may also contain a chain structure as part of the ring structure. The term "aromatic hydrocarbon group" refers to a hydrocarbon group that contains an aromatic ring structure as a ring structure. However, the group does not necessarily have to be composed solely of an aromatic ring structure, and may contain a chain structure or an alicyclic hydrocarbon structure as part of the ring structure. The term "main chain" of a polymer refers to the longest "trunk" portion of the atomic chain of the polymer. The term "side chain" of a polymer refers to a portion branched from the "trunk" of the polymer. The term "organic group" refers to an atomic group formed by removing any hydrogen atom from a carbon-containing compound (i.e., an organic compound).

[0016] <Liquid crystal alignment agent> The liquid crystal aligning agent of the present disclosure contains a polymer (P) having a partial structure represented by the following formula (1). [ka] (In formula (1), R 1 and R 2 are each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. 1 represents a single bond, an alkanediyl group having 1 to 6 carbon atoms, -O-, -CH2-O-* 1 , -O-(CH2) a -O-, -(CH2) b -COO-* 1 , -(CH2) b -COO-(CH2) a -O-* 1 or -O-CO-* 1a is an integer between 1 and 6. b is an integer between 0 and 6. * 1 " represents a bond to the benzene ring in formula (1). "*" represents a bond.)

[0017] <Polymer (P)> In the above formula (1), R 1 and R 2 When the group represented by the formula (I) is an alkyl group having 1 to 3 carbon atoms, the alkyl group may be linear or branched. Specific examples of the alkyl group having 1 to 3 carbon atoms include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group. Among these, R 1 and R 2 From the viewpoint of enhancing the effect of improving the narrow line adhesion of the liquid crystal alignment film, the alkyl group represented by the formula (I) is preferably a methyl group or an ethyl group, more preferably a methyl group.

[0018] R 1 and R 2 Both groups represented by R may be hydrogen atoms, but from the viewpoint of improving the resistance to high temperature and high humidity of the resulting liquid crystal alignment film, it is preferable that at least one of them is an alkyl group having 1 to 3 carbon atoms, and R 1 and R 2 It is more preferable that both R are alkyl groups having 1 to 3 carbon atoms. 1 and R 2 is R 1 is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R 2 is preferably an alkyl group having 1 to 3 carbon atoms, and R 1 and R 2 is more preferably an alkyl group having 1 to 3 carbon atoms.

[0019] X 1 When the group represented by the formula (I) is an alkanediyl group having 1 to 6 carbon atoms, the alkanediyl group may be linear or branched. 1 The alkanediyl group represented by X is preferably linear. 1From the viewpoint of increasing film density and polymer entanglement and enhancing the effects of improving narrow line adhesion and reliability (particularly reliability during long-term use in a high-temperature environment (hereinafter also referred to as "long-term thermal reliability") and high-temperature / high-humidity resistance), the number of carbon atoms in the alkanediyl group represented by the formula (I) is preferably 1 to 5, more preferably 1 to 4, and particularly preferably 1 to 3. For the same reasons, a and b are preferably 5 or less, more preferably 4 or less, and even more preferably 3 or less.

[0020] Specific examples of the partial structure represented by the above formula (1) include partial structures represented by the following formulas (1-1) to (1-33). [ka] [ka] [ka]

[0021] <Specific Embodiments of Polymer (P)> The main skeleton of the polymer (P) is not particularly limited, but from the viewpoint of good heat resistance, mechanical strength, affinity with liquid crystal, etc., it is preferably at least one selected from the group consisting of polyamic acid, polyimide, polyamic acid ester, polyorganosiloxane, and addition polymer. The polymer (P) may have the partial structure represented by the above formula (1) at the end of the main chain or in a side chain. In terms of a high introduction rate of the partial structure represented by the above formula (1) and ease of adjusting the introduction amount of the partial structure represented by the above formula (1), the polymer (P) preferably has a structural unit derived from a monomer having the partial structure represented by the above formula (1). Preferred examples of the polymer (P) are described below.

[0022] [Polyamic acid] The polyamic acid (hereinafter also referred to as "polyamic acid (P)") as the polymer (P) can be obtained by polymerizing a monomer having a partial structure represented by the above formula (1). Methods for producing the polyamic acid (P) include, for example, [1] a method of polymerizing a monomer containing a tetracarboxylic dianhydride having the partial structure represented by the above formula (1); and [2] a method of polymerizing a monomer containing a diamine (hereinafter also referred to as "specific diamine") having the partial structure represented by the above formula (1). Of these, the method using a specific diamine is preferred because the synthesis of the monomer is relatively easy.

[0023] (Tetracarboxylic acid dianhydride) Examples of the tetracarboxylic acid dianhydride used in the synthesis of the polyamic acid (P) include aliphatic tetracarboxylic acid dianhydrides, aromatic tetracarboxylic acid dianhydrides, etc. Examples of the aliphatic tetracarboxylic acid dianhydrides include chain tetracarboxylic acid dianhydrides and alicyclic tetracarboxylic acid dianhydrides.

[0024] Specific examples of these include chain tetracarboxylic dianhydrides such as 1,2,3,4-butanetetracarboxylic dianhydride; Alicyclic tetracarboxylic dianhydrides include 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 5-(2,5-dioxotetrahydrofuran-3-yl)-3a,4,5,9b-tetrahydronaphtho[1,2-c]furan-1,3-dione, 5-(2,5-dioxotetrahydrofuran-3-yl)-8-methyl-3a,4,5,9b-tetrahydronaphtho[1,2-c]furan-1,3-dione, 2,4,6,8-tetracarboxybicyclo[3.3.0]octane-2:4,6:8-dianhydride, cyclopentanetetracarboxylic dianhydride, cyclohexanetetracarboxylic dianhydride, and the like; Examples of aromatic tetracarboxylic dianhydrides include pyromellitic dianhydride, 4,4'-(hexafluoroisopropylidene)diphthalic anhydride, ethylene glycol bisanhydrotrimate, 4,4'-(hexafluoroisopropylidene)diphthalic anhydride, and 4,4'-carbonyldiphthalic anhydride. In addition, the tetracarboxylic dianhydrides described in JP-A-2010-97188 can be used. The tetracarboxylic dianhydrides can be used alone or in combination of two or more.

[0025] The tetracarboxylic acid dianhydride used in the synthesis of the polyamic acid preferably contains an aliphatic tetracarboxylic acid dianhydride (i.e., at least one selected from the group consisting of linear tetracarboxylic acid dianhydrides and alicyclic tetracarboxylic acid dianhydrides), and more preferably contains an alicyclic tetracarboxylic acid dianhydride, in terms of increasing the solubility of the polymer and enabling the production of a liquid crystal alignment film exhibiting good electrical properties. The amount of the alicyclic tetracarboxylic acid dianhydride used is preferably 20 mol % or more, more preferably 40 mol % or more, and even more preferably 50 mol % or more, based on the total amount of tetracarboxylic acid dianhydrides used in the synthesis of the polyamic acid (P).

[0026] (diamine) Specific diamines The specific diamine used in the synthesis of the polyamic acid (P) is not particularly limited as long as it has the partial structure represented by the above formula (1). The specific diamine may have the partial structure represented by the above formula (1) in its main chain or in its side chain. As the specific diamine, at least one selected from the group consisting of compounds represented by the following formula (2-1) and compounds represented by the following formula (2-2) can be preferably used. [ka] (In formula (2-1) and formula (2-2), Ar 1 and Ar 3 are each independently a trivalent aromatic ring group. 2 and Ar4 are each independently a divalent aromatic ring group. 2 and X 3 are each independently a single bond, -O-, -CH2-, -CO-, or -NR 3 -, -COO-, -OCO-, -CONR 3 -or-NR 3 CO-. R 3 is a hydrogen atom or a monovalent organic group. 1 , R 2 and X 1 is the same as the above formula (1).

[0027] In the above formula (2-1) and formula (2-2), Ar 1 and Ar 3 The trivalent aromatic ring group represented by the formula (I) is a group obtained by removing three hydrogen atoms from the ring portion of a substituted or unsubstituted aromatic ring. Examples of the aromatic ring include aromatic hydrocarbon rings such as a benzene ring, a biphenyl ring, a naphthalene ring, and an anthracene ring; and aromatic heterocycles such as a pyridine ring and a pyridazine ring. Among these, a benzene ring and a pyridine ring are preferred, and a benzene ring is more preferred. In addition, Ar 1 and Ar 3 A substituent may be introduced into the aromatic ring of the trivalent aromatic ring group represented by the following formula: Examples of the substituent include an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a halogen atom, a hydroxyl group, a cyano group, a nitro group, and a carboxyl group.

[0028] Ar 2 and Ar 4 The divalent aromatic ring group represented by the formula (I) is a group in which two hydrogen atoms have been removed from the ring portion of a substituted or unsubstituted aromatic ring. Specific examples of the aromatic ring include Ar 1 and Ar 3 Among these, a benzene ring, a biphenyl ring, a naphthalene ring and a pyridine ring are preferred, a benzene ring and a pyridine ring are more preferred, and a benzene ring is even more preferred. 2 and Ar 4A substituent (for example, an alkyl group having 1 to 3 carbon atoms, a halogen atom, etc.) may be introduced into the aromatic ring of the divalent aromatic ring group represented by the following formula:

[0029] R 3 When the group represented by is a monovalent organic group, R 3 Examples of the monovalent organic group represented by R include a monovalent hydrocarbon group having 1 to 10 carbon atoms and a monovalent thermally detachable group. 3 Specific examples of when is a monovalent hydrocarbon group include an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 4 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, and an aralkyl group having 6 to 10 carbon atoms. Of these, an alkyl group having 1 to 6 carbon atoms, a cyclohexyl group, and a phenyl group are preferred, and an alkyl group having 1 to 3 carbon atoms is more preferred.

[0030] R 3 When R is a monovalent thermally detachable group, 3 The thermally detachable group represented by the formula (I) is preferably a monovalent group that is detached by heating during film formation. Specific examples of the thermally detachable group include a tert-butoxycarbonyl group (Boc group), a benzyloxycarbonyl group, a 1,1-dimethyl-2-haloethyloxycarbonyl group, an allyloxycarbonyl group, a 2-(trimethylsilyl)ethoxycarbonyl group, and a 9-fluorenylmethyloxycarbonyl group. Among these, the Boc group is particularly preferred because it has excellent thermal detachment properties and can reduce the amount of the detached structure remaining in the film.

[0031] Specific examples of the specific diamine include, as the compound represented by the above formula (2-1), for example, compounds represented by each of the following formulas (2-1-1) to (2-1-32); and as the compound represented by the above formula (2-2), for example, compounds represented by each of the following formulas (2-2-1) to (2-2-4).

[0032] [ka] [ka] [ka] [ka] [ka]

[0033] [ka]

[0034] The specific diamine can be synthesized by appropriately combining standard methods in organic chemistry. One example of the synthesis method is to synthesize a dinitro intermediate having a nitro group instead of the primary amino group in the above formula (2-1) and the above formula (2-2), and then animate the nitro group of the obtained dinitro intermediate using an appropriate reduction system.

[0035] The method for synthesizing the dinitro intermediate is not particularly limited and can be appropriately selected depending on the target compound. For example, a dinitro compound having a halogenated alkyl group, a halogen group, an acid chloride group, or an alkyl acid chloride group is reacted with a specific compound having a ring structure and a hydroxyl group in the above formula (2-1) or formula (2-2) in an organic solvent in the presence of a base catalyst (sodium hydroxide, triethylamine, potassium carbonate, etc.). However, the method for synthesizing the specific dinitro intermediate is not limited to the above.

[0036] The reduction reaction of the dinitro intermediate can be preferably carried out in an organic solvent using a catalyst such as palladium on carbon, platinum oxide, zinc, iron, tin, nickel, platinum on carbon, or osmium on carbon. Examples of the organic solvent used here include ethyl acetate, toluene, tetrahydrofuran, and alcohols. Two or more of these organic solvents may also be used in combination. However, the synthesis procedures for the compounds represented by formula (2-1) and formula (2-2) are not limited to the above methods.

[0037] Other diamines The diamine used in the synthesis of the polyamic acid (P) may be the specific diamine alone, or a diamine not having the partial structure represented by the above formula (1) (hereinafter also referred to as "other diamine") may be used in combination. Examples of other diamines include aliphatic diamines, aromatic diamines, and diaminoorganosiloxanes. Examples of aliphatic diamines include linear diamines and alicyclic diamines.

[0038] Specific examples of other diamines include chain diamines such as metaxylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, and hexamethylenediamine; Alicyclic diamines such as 1,4-diaminocyclohexane and 4,4'-methylenebis(cyclohexylamine); Aromatic diamines include p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4-aminophenyl-4-aminobenzoate, 4,4'-diaminoazobenzene, 1,5-bis(4-aminophenoxy)pentane, 1,2-bis(4-aminophenoxy)ethane, 1,6-bis(4-aminophenoxy)hexane, bis[2-(4-aminophenyl)ethyl]hexanedioic acid, 2,6-diaminopyridine, 1,4-bis-(4-aminophenyl)-piperazine, 2,2'-dimethyl-4,4'-diaminobiphenyl, and 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl. Main chain diamines such as 4,4'-diaminodiphenyl ether, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis(4-aminophenyl)hexafluoropropane, 4,4'-(phenylenediisopropylidene)bisaniline, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-[4,4'-propane-1,3-diylbis(piperidine-1,4-diyl)]dianiline, 4,4'-diaminobenzanilide, 4,4'-diaminostilbenzene, and 1,4-bis(4-aminophenyl)-piperazine: Dodecanoxy-2,4-diaminobenzene, pentadecanoxy-2,4-diaminobenzene, hexadecanoxy-2,4-diaminobenzene, octadecanoxy-2,4-diaminobenzene, pentadecanoxy-2,5-diaminobenzene, octadecanoxy-2,5-diaminobenzene, cholestanyloxy-3,5-diaminobenzene, cholestanyloxy-3,5-diaminobenzene, cholestanyloxy-2,4-diaminobenzene, cholestanyloxy-2,4-diaminobenzene, 3,5-di Cholestanyl aminobenzoate, cholestenyl 3,5-diaminobenzoate, lanostaniyl 3,5-diaminobenzoate, 3,6-bis(4-aminobenzoyloxy)cholestane, 3,6-bis(4-aminophenoxy)cholestane, 4-(4'-trifluoromethoxybenzoyloxy)cyclohexyl-3,5-diaminobenzoate, 1,1-bis(4-((aminophenyl)methyl)phenyl)-4-butylcyclohexane, 5ξ-cholestan-3-yl 3,5-diaminobenzoate, the following formula (E-1): [ka] (In formula (E-1), X I and X II are each independently a single bond, -O-, *-COO-, or *-OCO- (where * indicates the bond to the diaminophenyl group). I is an alkanediyl group having 1 to 3 carbon atoms. II R is a single bond or an alkanediyl group having 1 to 3 carbon atoms. III is an alkyl group, alkoxy group, fluoroalkyl group, or fluoroalkoxy group having 1 to 20 carbon atoms. a is 0 or 1. b is an integer of 0 to 3. c is an integer of 0 to 2. d is 0 or 1, provided that 1≦a+b+c≦3. Side chain diamines such as compounds represented by the formula: Examples of diaminoorganosiloxanes include 1,3-bis(3-aminopropyl)-tetramethyldisiloxane, and the diamines described in JP-A-2010-97188 can also be used. In synthesizing the polyamic acid (P), the other diamines can be used alone or in combination of two or more.

[0039] In the polyamic acid (P), the content of the partial structure represented by the above formula (1) is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 15 mol% or more, based on the total diamine units contained in the polyamic acid (P). Furthermore, the content of the partial structure represented by the above formula (1) is preferably 95 mol% or less, more preferably 90 mol% or less, and even more preferably 85 mol% or less, based on the total diamine units contained in the polyamic acid (P). A content of the partial structure represented by the above formula (1) in the polyamic acid (P) within the above range is advantageous in that it can sufficiently improve narrow line adhesion, long-term thermal reliability, and high-temperature / high-humidity resistance.

[0040] Synthesis of polyamic acid The polyamic acid (P) can be obtained by reacting the above-mentioned tetracarboxylic dianhydride with a diamine, optionally together with a molecular weight modifier. The ratio of the tetracarboxylic dianhydride and the diamine used in the synthesis reaction of the polyamic acid (P) is preferably such that 0.2 to 2 equivalents of the acid anhydride group of the tetracarboxylic dianhydride are used per equivalent of the amino group of the diamine.

[0041] Examples of molecular weight modifiers include acid monoanhydrides such as maleic anhydride, phthalic anhydride, and itaconic anhydride; monoamine compounds such as aniline, cyclohexylamine, and n-butylamine; and monoisocyanate compounds such as phenyl isocyanate and naphthyl isocyanate. The proportion of the molecular weight modifier used is preferably 20 parts by mass or less per 100 parts by mass of the total of the tetracarboxylic dianhydride and diamine used.

[0042] The synthesis reaction of the polyamic acid (P) is preferably carried out in an organic solvent. The reaction temperature is preferably −20° C. to 150° C., and the reaction time is preferably 0.1 to 24 hours. Examples of organic solvents used in the reaction include aprotic polar solvents, phenolic solvents, alcohols, ketones, esters, ethers, halogenated hydrocarbons, and hydrocarbons. Particularly preferred organic solvents include one or more selected from the group consisting of N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethyl sulfoxide, γ-butyrolactone, tetramethylurea, hexamethylphosphortriamide, m-cresol, xylenol, and halogenated phenols, or a mixture of one or more of these solvents with other organic solvents (e.g., butyl cellosolve, diethylene glycol diethyl ether, etc.). The amount (a) of the organic solvent used is preferably an amount such that the total amount (b) of the tetracarboxylic dianhydride and the diamine is 0.1 to 50% by mass relative to the total amount (a+b) of the reaction solution.

[0043] In this manner, a reaction solution containing the polyamic acid (P) dissolved therein is obtained. This reaction solution may be used as is for preparing a liquid crystal aligning agent, or the polyamic acid (P) contained in the reaction solution may be isolated and then used for preparing a liquid crystal aligning agent.

[0044] (Polyamic acid ester) The polyamic acid ester (hereinafter also referred to as "polyamic acid ester (P)") as the polymer (P) can be obtained, for example, by [I] a method of reacting the polyamic acid (P) obtained by the above synthesis reaction with an esterifying agent, [II] a method of reacting a tetracarboxylic acid diester with a diamine including a specific diamine, or [III] a method of reacting a tetracarboxylic acid diester dihalide with a diamine including a specific diamine. The polyamic acid ester (P) contained in the liquid crystal aligning agent of the present disclosure may have only an amic acid ester structure, or may be a partially esterified product in which an amic acid structure and an amic acid ester structure coexist. The reaction solution in which the polyamic acid ester (P) is dissolved may be used directly for preparing the liquid crystal aligning agent, or the polyamic acid ester (P) contained in the reaction solution may be isolated and then used for preparing the liquid crystal aligning agent.

[0045] (Polyimide) The polyimide (hereinafter also referred to as "polyimide (P)") as the polymer (P) can be obtained, for example, by dehydrating and cyclizing the polyamic acid (P) synthesized as described above to form an imidized product. The polyimide (P) may be a fully imidized product in which all of the amic acid structures contained in its precursor polyamic acid (P) have been dehydrated and cyclized, or a partially imidized product in which only a portion of the amic acid structures have been dehydrated and cyclized, resulting in both amic acid structures and imide ring structures. The polyimide (P) preferably has an imidization rate of 20% or more, more preferably 30 to 95%. The imidization rate is the ratio, expressed as a percentage, of the number of imide ring structures to the total number of amic acid structures and imide ring structures in the polyimide. Here, some of the imide rings may be isoimide rings.

[0046] The dehydration ring closure of the polyamic acid (P) is preferably carried out by dissolving the polyamic acid (P) in an organic solvent, adding a dehydrating agent and a dehydration ring closure catalyst to the solution, and heating as necessary. In this method, the dehydrating agent may be, for example, an acid anhydride such as acetic anhydride, propionic anhydride, or trifluoroacetic anhydride. The amount of the dehydrating agent used is preferably 0.01 to 20 mol per mol of the amic acid structure of the polyamic acid (P). The dehydration ring closure catalyst may be, for example, a tertiary amine such as pyridine, collidine, lutidine, or triethylamine. The amount of the dehydration ring closure catalyst used is preferably 0.01 to 10 mol per mol of the dehydrating agent used. Examples of organic solvents used in the dehydration ring closure reaction include the organic solvents exemplified for use in the synthesis of the polyamic acid (P). The reaction temperature for the dehydration ring closure reaction is preferably 0 to 180°C. The reaction time is preferably 1.0 to 120 hours. The reaction solution containing the polyimide (P) obtained by the above reaction may be used for preparing a liquid crystal aligning agent as it is, or the polyimide (P) may be isolated and then used for preparing a liquid crystal aligning agent. The polyimide (P) can also be obtained by imidizing a polyamic acid ester (P).

[0047] The solution viscosity of the polyamic acid, polyamic acid ester, and polyimide contained in the liquid crystal alignment agent is preferably 10 to 800 mPa·s, and more preferably 15 to 500 mPa·s, when the solution is made into a 10% by mass solution. The solution viscosity (mPa·s) is a value measured at 25°C using an E-type rotational viscometer for a 10% by mass polymer solution prepared using a good solvent for the polymer (e.g., γ-butyrolactone, N-methyl-2-pyrrolidone, etc.).

[0048] The polystyrene-equivalent weight average molecular weight (Mw) of the polyamic acid, polyamic acid ester, and polyimide measured by gel permeation chromatography (GPC) is preferably 1,000 to 500,000, and more preferably 5,000 to 100,000. The molecular weight distribution (Mw / Mn), expressed as the ratio of Mw to the polystyrene-equivalent number average molecular weight (Mn) measured by GPC, is preferably 15 or less, and more preferably 10 or less.

[0049] (Polyorganosiloxane) The method for producing the polyorganosiloxane (hereinafter also referred to as "polysiloxane (P)") as the polymer (P) is not particularly limited as long as it has the partial structure represented by the above formula (1). The polysiloxane (P) can be obtained, for example, by the hydrolysis and condensation reaction of a hydrolyzable silane compound. Specific examples include the following methods [1] and [2].

[0050] [1] A method of synthesizing an epoxy group-containing polyorganosiloxane by hydrolysis and condensation of a hydrolyzable silane compound (ms-1) having an epoxy group, or a mixture of the silane compound (ms-1) and other silane compounds, and then reacting the obtained epoxy group-containing polyorganosiloxane with a carboxylic acid having a partial structure represented by the above formula (1) (hereinafter also referred to as "specific carboxylic acid"). [2] A method of hydrolyzing and condensing a hydrolyzable silane compound (ms-2) having a partial structure represented by the above formula (1), or a mixture of the silane compound (ms-2) and another silane compound. Among these, method [1] is preferable because it is simple and easy and can increase the introduction rate of the partial structure represented by the above formula (1) in the polysiloxane (P).

[0051] Specific examples of the silane compound (ms-1) include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, 3-(3,4-epoxycyclohexyl)propyltrimethoxysilane, etc. As the silane compound (ms-1), one of these compounds can be used alone, or two or more can be used in combination.

[0052] The other silane compounds used in the synthesis of the epoxy group-containing polyorganosiloxane are not particularly limited as long as they are hydrolyzable silane compounds, and specific examples thereof include alkoxysilanes such as tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, dimethyldimethoxysilane, and dimethyldiethoxysilane; Nitrogen- and sulfur-containing alkoxysilanes, such as 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, mercaptomethyltrimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-(3-cyclohexylamino)propyltrimethoxysilane, and N-2-(aminoethyl)-3-aminopropyltrimethoxysilane; Examples of the silane compounds include unsaturated hydrocarbon-containing alkoxysilanes such as 3-(meth)acryloyloxypropyltrimethoxysilane, 3-(meth)acryloyloxypropyltriethoxysilane, 6-(meth)acryloyloxyhexyltrimethoxysilane, 3-(meth)acryloxypropylmethyldimethoxysilane, 3-(meth)acryloxypropylmethyldiethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, and p-styryltrimethoxysilane; and trimethoxysilylpropylsuccinic anhydride. These other silane compounds may be used alone or in combination of two or more. In this specification, the term "(meth)acryloxy" encompasses both "acryloxy" and "methacryloxy."

[0053] The hydrolysis and condensation reaction of silane compounds can be carried out by reacting one or more of the above-mentioned silane compounds with water, preferably in the presence of a suitable catalyst and organic solvent. The proportion of water used in the reaction is preferably 1 to 30 moles per mole of the total amount of silane compounds. Examples of catalysts include acids, alkali metal compounds, organic bases, titanium compounds, and zirconium compounds. The amount of catalyst used varies depending on the type of catalyst, reaction conditions such as temperature, and should be appropriately determined. For example, the amount is preferably 0.01 to 3 moles per mole of the total amount of silane compounds. Examples of organic solvents used include hydrocarbons, ketones, esters, ethers, and alcohols. Among these, water-insoluble or slightly water-soluble organic solvents are preferred. The proportion of the organic solvent used is preferably 10 to 10,000 parts by mass per 100 parts by mass of the total amount of silane compounds used in the reaction.

[0054] The hydrolysis-condensation reaction is preferably carried out by heating, for example, in an oil bath. The heating temperature is preferably 130°C or lower, and the heating time is preferably 0.5 to 12 hours. After the reaction is complete, the organic solvent layer separated from the reaction solution is dried with a desiccant, if necessary, and the solvent is then removed to obtain the desired polyorganosiloxane. The synthesis of polyorganosiloxane is not limited to the hydrolysis-condensation reaction described above; for example, it may be carried out by reacting a hydrolyzable silane compound in the presence of oxalic acid and an alcohol.

[0055] In the method [1] above, the epoxy group-containing polyorganosiloxane obtained by the above reaction is then reacted with a specific carboxylic acid, whereby the epoxy group of the epoxy group-containing polyorganosiloxane reacts with the carboxyl group of the specific carboxylic acid to obtain a polysiloxane (P) having the partial structure represented by the above formula (1) in its side chain.

[0056] Specific examples of the specific carboxylic acid include compounds represented by the following formulas (3-1) to (3-4). [ka]

[0057] The content of the partial structure represented by the above formula (1) in one molecule of polysiloxane (P) is preferably 5 mol % or more, more preferably 10 mol % or more, and even more preferably 15 mol % or more, based on the silicon atoms in polysiloxane (P). Furthermore, the content of the partial structure represented by the above formula (1) in one molecule of polysiloxane (P) is preferably 70 mol % or less, more preferably 60 mol % or less, and even more preferably 50 mol % or less, based on the silicon atoms in polysiloxane (P).

[0058] In addition, when synthesizing the polysiloxane (P), the carboxylic acid used in the reaction with the epoxy group-containing polyorganosiloxane may be the specific carboxylic acid alone, or other carboxylic acids other than the specific carboxylic acid may be used in combination. The other carboxylic acid may be any carboxylic acid that does not have the partial structure represented by the above formula (1), and various carboxylic acids can be used. Examples of other carboxylic acids include carboxylic acids having a vertical alignment group (mesogenic structure, etc.).

[0059] The reaction of the epoxy group-containing polyorganosiloxane with the carboxylic acid can be preferably carried out in the presence of a catalyst and an organic solvent. Examples of the catalyst include organic bases and compounds known as curing accelerators (e.g., tertiary organic amines, quaternary organic amines, quaternary ammonium salts, etc.) that accelerate the reaction of epoxy compounds. The amount of catalyst used is preferably 100 parts by mass or less, more preferably 0.1 to 20 parts by mass, per 100 parts by mass of the epoxy group-containing polyorganosiloxane.

[0060] Examples of organic solvents used in the above reaction include hydrocarbons, ethers, esters, ketones, amides, and alcohols. The organic solvent is preferably used in a proportion such that the solids concentration (the proportion of the total mass of components other than the solvent in the reaction solution to the total mass of the solution) is 0.1% by mass or more, and more preferably 5 to 50% by mass. In the above reaction, the reaction temperature is preferably 0 to 200°C, more preferably 50 to 150°C. The reaction time is preferably 0.1 to 50 hours, more preferably 0.5 to 20 hours. After completion of the reaction, it is preferable to wash the organic solvent layer separated from the reaction solution with water. After washing with water, the organic solvent layer is dried with an appropriate desiccant, if necessary, and the solvent is then removed to obtain the target polysiloxane (P).

[0061] The polysiloxane (P), when prepared into a 10% by mass solution, preferably has a solution viscosity of 1 to 500 mPa·s, and more preferably 3 to 200 mPa·s.The polysiloxane (P) has a weight average molecular weight (Mw) measured by GPC in terms of polystyrene of preferably 1,000 to 200,000, more preferably 2,000 to 50,000, and even more preferably 3,000 to 20,000.

[0062] (addition polymer) The method for producing the addition polymer (hereinafter also referred to as "addition polymer (P)") as polymer (P) is not particularly limited as long as it has the partial structure represented by the above formula (1). The addition polymer (P) is preferably a polymer having a structural unit derived from a monomer (hereinafter also referred to as "unsaturated monomer") having a polymerizable carbon-carbon unsaturated bond. The addition polymer (P) can be obtained, for example, by polymerizing an unsaturated monomer (ma-1) having the partial structure represented by the above formula (1), or a mixture of the unsaturated monomer (ma-1) and another unsaturated monomer.

[0063] As the unsaturated monomer, any monomer having a polymerizable carbon-carbon unsaturated bond can be used. Examples of such monomers include compounds having a (meth)acryloyl group, a vinyl group, a vinylphenyl group, a maleimide group, etc. As the unsaturated polymer (P), at least one selected from the group consisting of poly(meth)acrylate, a maleimide polymer, and a styrene-maleimide copolymer can be preferably used, since it can form a liquid crystal alignment film having excellent liquid crystal alignment properties.

[0064] The unsaturated monomer (ma-1) is not particularly limited as long as it has the partial structure represented by the above formula (1). Specific examples of the unsaturated monomer (ma-1) include compounds represented by each of the following formulas (4-1) to (4-10). [ka]

[0065] Specific examples of other unsaturated monomers include unsaturated carboxylic acids such as (meth)acrylic acid, α-ethylacrylic acid, maleic acid, fumaric acid, and vinylbenzoic acid; unsaturated carboxylic acid esters such as alkyl (meth)acrylates (e.g., methyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, etc.), cycloalkyl (meth)acrylates, benzyl (meth)acrylate, trimethoxysilylpropyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, glycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, 3,4-epoxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate glycidyl ether; unsaturated polycarboxylic acid anhydrides such as maleic anhydride; Aromatic vinyl compounds such as styrene, methylstyrene, divinylbenzene, and 4-(glycidyloxymethyl)styrene; conjugated diene compounds such as 1,3-butadiene and 2-methyl-1,3-butadiene; Examples of the unsaturated monomer include maleimide compounds such as N-methylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, 4-(2,5-dioxo-3-pyrrolin-1-yl)benzoic acid, N-(4-glycidyloxyphenyl)maleimide, N-glycidylmaleimide, 3-maleimidobenzoic acid, 3-maleimidopropionic acid, 3-(2,5-dioxo-3-pyrrolin-1-yl)benzoic acid, and methyl 4-(2,5-dioxo-3-pyrrolin-1-yl)benzoate. When synthesizing the addition polymer (P), one type of other unsaturated monomer may be used alone, or two or more types may be used in combination.

[0066] The content of the partial structure represented by formula (1) in one molecule of addition polymer (P) is preferably 2 mol % or more, more preferably 5 mol % or more, and even more preferably 10 mol % or more, based on all structural units in addition polymer (P). Also, the content of the partial structure represented by formula (1) in one molecule of addition polymer (P) is preferably 60 mol % or less, more preferably 50 mol % or less, and even more preferably 40 mol % or less, based on all structural units in addition polymer (P).

[0067] The addition polymer (P) can be obtained, for example, by polymerizing the monomers in the presence of a polymerization initiator. The polymerization initiator used is preferably an azo compound such as 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), or 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile). The polymerization initiator is preferably used in an amount of 0.01 to 30 parts by mass relative to 100 parts by mass of all the monomers used in the reaction.

[0068] The polymerization reaction is preferably carried out in an organic solvent. Examples of organic solvents used in the reaction include alcohols, ethers, ketones, amides, esters, and hydrocarbon compounds, with diethylene glycol ethyl methyl ether and propylene glycol monomethyl ether acetate being preferred. The reaction temperature is preferably 30°C to 120°C, and the reaction time is preferably 1 to 36 hours. The amount of organic solvent (a) used is preferably such that the total amount of monomers (b) used in the reaction is 0.1 to 60% by mass relative to the total amount of the reaction solution (a+b).

[0069] The addition polymer (P) preferably has a weight average molecular weight (Mw) in terms of polystyrene measured by GPC of 250 to 500,000, more preferably 500 to 100,000. The molecular weight distribution (Mw / Mn), which is the ratio of Mw to the number average molecular weight (Mn) in terms of polystyrene measured by GPC, is preferably 8 or less, more preferably 6 or less.

[0070] The method for producing the addition polymer (P) is not limited to the above. For example, the addition polymer (P) can also be obtained by a method in which a monomer containing an unsaturated monomer having an epoxy group is polymerized in the presence of a polymerization initiator, and then the resulting polymer is reacted with a specific carboxylic acid.

[0071] The polymer (P) preferably contains a structural unit derived from a monomer (hereinafter also referred to as "nitrogen-containing monomer") having at least one partial structure selected from the group consisting of a nitrogen-containing heterocycle, an amino group, a protected amino group, an amido group, a protected amido group, a urea group, and a protected urea group. The nitrogen-containing monomer is a group capable of introducing at least one partial structure selected from the group consisting of a nitrogen-containing heterocycle, an amino group, a protected amino group, an amido group, a protected amido group, a urea group, and a protected urea group into the polymer (P). When the polymer (P) contains a structural unit derived from a nitrogen-containing monomer, it is advantageous in that it can further improve long-term thermal reliability in addition to the improvement effect achieved by introducing the partial structure represented by the above formula (1).

[0072] Examples of the nitrogen-containing heterocycle include pyrrole, imidazole, pyrazole, triazole, pyridine, pyrimidine, pyridazine, pyrazine, indole, benzimidazole, purine, quinoline, isoquinoline, naphthyridine, quinoxaline, phthalazine, triazine, carbazole, acridine, piperidine, piperazine, pyrrolidine, hexamethyleneimine, etc. Among these, the nitrogen-containing heterocycle possessed by the nitrogen-containing monomer is preferably at least one selected from the group consisting of pyridine, pyrimidine, pyrazine, piperidine, piperazine, quinoline, benzimidazole, carbazole, and acridine.

[0073] The amino group, protected amino group, amido group, protected amido group, urea group and protected urea group preferably have a structure represented by the following formula (N-1). [ka] (In formula (N-1), R 20 is a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, or a monovalent thermally detachable group. "*" represents a bond.

[0074] In the above formula (N-1), R 20 Examples of the monovalent hydrocarbon group represented by R include alkyl groups such as methyl, ethyl, and propyl; cycloalkyl groups such as cyclohexyl; and aryl groups such as phenyl and methylphenyl. 20 The monovalent thermally eliminable group represented by R 3 The explanations of specific and preferred examples when R is a monovalent thermally detachable group apply. 20 is preferably a hydrogen atom, a methyl group, or a t-butoxycarbonyl group. When the nitrogen-containing monomer has an amino group, the amino group is preferably a group different from the group participating in the polymerization, and is more preferably a secondary amino group or a tertiary amino group.

[0075] Among the above-mentioned nitrogen-containing monomers, monomers having at least one selected from the group consisting of a nitrogen-containing heterocycle, a protected amino group, and a protected amide group are preferred because of their high effect of improving long-term thermal reliability, and monomers having a nitrogen-containing heterocycle are particularly preferred. Among these, monomers capable of introducing at least one selected from the group consisting of a nitrogen-containing heterocycle, a protected amino group, and a protected amide group into the side chain of a polymer are preferred, and monomers capable of introducing a nitrogen-containing heterocycle into the side chain of a polymer are even more preferred. The nitrogen-containing monomer is preferably a compound that does not have the partial structure represented by formula (1) above. That is, the nitrogen-containing structure is preferably introduced into the polymer (P) separately from the structural unit having the partial structure represented by formula (1) above.

[0076] When the polymer (P) contains a structural unit derived from a nitrogen-containing monomer, the polymer (P) is preferably at least one selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide. In this case, the nitrogen-containing monomer is preferably a diamine, more preferably a diamine having at least one partial structure selected from the group consisting of a nitrogen-containing heterocycle, a secondary amino group, a tertiary amino group, a protected amino group, an amide group, a protected amide group, a urea group, and a protected urea group.

[0077] Specific examples of when the nitrogen-containing monomer is a diamine include 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, 1,4-bis-(4-aminophenyl)-piperazine, 3,6-diaminoacridine, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, N,N'-bis(4-aminophenyl)-benzidine, N,N'-bis(4-aminophenyl)-N,N'-dimethylbenzidine, and compounds represented by the following formulas (N-1-1) to (N-1-17). [ka] [ka]

[0078] In polymer (P), the proportion of structural units derived from nitrogen-containing monomers is preferably 1 mol% or more, more preferably 2 mol% or more, and even more preferably 5 mol% or more, based on the total amount of structural units contained in polymer (P), from the viewpoint of sufficiently improving long-term thermal reliability. Furthermore, the proportion of structural units derived from nitrogen-containing monomers is preferably 40 mol% or less, more preferably 35 mol% or less, based on the total amount of structural units contained in polymer (P). The nitrogen-containing monomers may be used singly or in combination of two or more.

[0079] When the polymer (P) contains a structural unit derived from a nitrogen-containing monomer, the polymer (P) preferably further contains a structural unit derived from a monomer having a carboxyl group or a protected carboxyl group (hereinafter also referred to as a "carboxyl group-containing monomer"). By further introducing a structural unit derived from a carboxyl group-containing monomer into the polymer (P), the electrical properties of the liquid crystal alignment film can be improved, and it is advantageous in that long-term thermal reliability and high-temperature and high-humidity resistance can be improved.

[0080] Specific examples of when the carboxyl group-containing monomer is a diamine include 3,5-diaminobenzoic acid, 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 4,4'-diaminobiphenyl-3,3'-dicarboxylic acid, 4,4'-diaminobiphenyl-2,2'-dicarboxylic acid, 4,4'-diaminodiphenylmethane-3,3'-dicarboxylic acid, and compounds in which the hydrogen atoms of the carboxyl groups of these diamines are substituted with thermally detachable groups (for example, tertiary hydrocarbon groups, groups having an acetal structure, etc.).

[0081] When polymer (P) contains structural units derived from carboxyl group-containing monomers, the proportion of structural units derived from carboxyl group-containing monomers is preferably 1 mol% or more, more preferably 2 mol% or more, and even more preferably 5 mol% or more, based on the total amount of structural units contained in polymer (P), from the viewpoint of sufficiently improving long-term thermal reliability and high-temperature, high-humidity resistance. Furthermore, the proportion of structural units derived from carboxyl group-containing monomers is preferably 40 mol% or less, more preferably 35 mol% or less, based on the total amount of structural units contained in polymer (P). One type of carboxyl group-containing monomer may be used alone, or two or more types may be used in combination.

[0082] The polymer (P) may also contain a structural unit derived from a monomer (hereinafter also referred to as an "orientation group-containing monomer") having at least one group (hereinafter also referred to as an "orientation group-containing monomer") in a side chain selected from the group consisting of an alkyl group having 4 to 30 carbon atoms, a halogenated alkyl group having 4 to 30 carbon atoms, an alkoxy group having 4 to 30 carbon atoms, a halogenated alkoxy group having 4 to 30 carbon atoms, a group having a polycyclic structure in which two or more rings are bonded directly or via a divalent linking group, and a group having a steroid skeleton, and not having the partial structure represented by the above formula (1).

[0083] Specific examples of the vertical alignment group include a group represented by the following formula (5). *-L 1 -R 11 -R 12 -R 13 -R 14 …(5) (In formula (5), L 1 is a single bond, -O-, -CO-, -COO-* 1 , -OCO-* 1 , -NR 15 -, -NR 15 -CO-* 1 , -CO-NR 15 -* 1 , an alkanediyl group having 1 to 6 carbon atoms, -OR 16 -* 1 , or -R 16 -O-* 1 (However, R 15 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms, and R 16 is an alkanediyl group having 1 to 3 carbon atoms. 1 " is R 11 This indicates that it is a bond with R. 11 and R 13 are each independently a single bond, a phenylene group, or a cycloalkylene group, and R 12 represents a single bond, a phenylene group, a cycloalkylene group, -R 17 -B 1 -* 2 , or -B 1 -R 17 -* 2 (However, R17 is a phenylene group or a cycloalkylene group, and B 1 -COO-* 3 , -OCO-* 3 or an alkanediyl group having 1 to 3 carbon atoms. 2 " is R 13 It indicates that it is a bond with "* 3 " is R 17 This indicates that it is a bond with R. 14 is a hydrogen atom, a fluorine atom, a cyano group, an alkyl group having 1 to 30 carbon atoms, a fluoroalkyl group having 1 to 30 carbon atoms, an alkoxy group having 1 to 30 carbon atoms, a fluoroalkoxy group having 1 to 30 carbon atoms, or a hydrocarbon group having a steroid skeleton and 17 to 51 carbon atoms. 11 , R 12 and R 13 If all of are single bonds, R 14 is an alkyl group having 4 to 30 carbon atoms, a fluoroalkyl group having 4 to 30 carbon atoms, an alkoxy group having 4 to 30 carbon atoms, a fluoroalkoxy group having 4 to 30 carbon atoms, or a hydrocarbon group having a steroid skeleton and 17 to 51 carbon atoms. "*" indicates a bond.)

[0084] In the above formula (5), L 1 , B 1 Alkanediyl groups of the formula R 14 The alkyl group, fluoroalkyl group, alkoxy group and fluoroalkoxy group in R are preferably linear. 14 Examples of the group having a steroid skeleton include a cholestanyl group, a cholesteryl group, and a lanostaniyl group. 11 , R 12 and R 13 At least two of these preferably have a phenylene group or a cycloalkylene group.

[0085] Specific examples of the partial structure represented by the above formula (5) include the partial structures represented by the following formulas (5-1) to (5-12), a cholestanyloxy group, a cholestanyloxycarbonyl group, a cholesteryloxy group, a lanostannyloxy group, etc. However, the vertically aligning group is not limited to these specific examples. [ka]

[0086] In polymer (P), the proportion of structural units derived from the orienting group-containing monomer is preferably 1 mol % or more, more preferably 2 mol % or more, and even more preferably 5 mol % or more, based on the total amount of structural units contained in polymer (P), from the viewpoint of obtaining good pretilt angle characteristics. Furthermore, the proportion of structural units derived from the orienting group-containing monomer is preferably 30 mol % or less, more preferably 20 mol % or less, based on the total amount of structural units contained in polymer (P). The orienting group-containing monomer may be used singly or in combination of two or more.

[0087] In the polymer (P), the structural unit derived from the alignment group-containing monomer is introduced separately from the structural unit having the partial structure represented by the above formula (1). In this case, the amount of the structural unit derived from the alignment group-containing monomer introduced can be adjusted independently of the amount of the partial structure represented by the above formula (1). Furthermore, even when a vertical alignment group is introduced into the polymer, a liquid crystal alignment film with high film density can be formed, which is advantageous in that a liquid crystal alignment film with good narrow line adhesion, long-term thermal reliability, and high-temperature and high-humidity resistance can be obtained.

[0088] The content of the polymer (P) in the liquid crystal aligning agent is preferably 2% by mass or more, more preferably 5% by mass or more, and even more preferably 10% by mass or more, based on the total amount of polymer components contained in the liquid crystal aligning agent. The polymer (P) used to prepare the liquid crystal aligning agent may be one type or a combination of two or more types. A liquid crystal aligning agent containing the polymer (P) can provide a liquid crystal alignment film that exhibits good pretilt angle characteristics, is highly reliable even when used under harsh conditions, and has excellent narrow-line adhesion.

[0089] <Other ingredients> The liquid crystal aligning agent of the present disclosure contains the polymer (P) as described above, but may contain other components in addition to the polymer (P) as necessary.

[0090] (Polymer (Q)) The liquid crystal aligning agent of the present disclosure may further contain a polymer (hereinafter also referred to as "polymer (Q)") that does not have the partial structure represented by the above formula (1) for the purpose of further improving the liquid crystal alignment properties and electrical properties.

[0091] Examples of the polymer (Q) include polyamic acid, polyimide, polyamic acid ester, polyamide, polyorganosiloxane, addition polymer, etc. From the viewpoints of improving electrical properties, affinity with liquid crystal, mechanical strength, and affinity with the polymer (P), the polymer (Q) is preferably at least one selected from the group consisting of polyamic acid, polyimide, polyamic acid ester, polyorganosiloxane, and addition polymer, and more preferably at least one selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, and polyorganosiloxane.

[0092] When the liquid crystal aligning agent contains polymer (Q), the content of polymer (Q) is preferably 1 part by mass or less, more preferably 2 parts by mass or less, and even more preferably 5 parts by mass or less, relative to 100 parts by mass of the total amount of polymer (P) and polymer (Q) contained in the liquid crystal aligning agent, from the viewpoint of achieving a balanced improvement effect by blending polymer (P) and polymer (Q).

[0093] (Crosslinking agent) The liquid crystal aligning agent of the present disclosure may further contain a crosslinking agent. By further containing a crosslinking agent, the film density of the liquid crystal alignment film can be increased, which is preferable in that the effect of improving narrow line adhesion can be further enhanced.

[0094] Examples of the crosslinking agent include compounds having a functional group (hereinafter also referred to as a "crosslinkable group") that can react with a functional group (e.g., an amino group, a carboxyl group, an epoxy group, a polymeric unsaturated bond group, etc.) possessed by the polymer (P) or the polymer (Q). Specific examples of the crosslinkable group include a cyclic ether group, a carboxyl group, a cyclic carbonate group, an alcoholic hydroxyl group (e.g., a methylol group), a β-hydroxyamide group, an amino group, a protected amino group, a protected isocyanate group, a trialkoxysilyl group, a polymerizable unsaturated bond group, and a maleimide group. The number of crosslinkable groups possessed by the crosslinking agent is preferably 2 or more, more preferably 3 or more, and even more preferably 3 to 6.

[0095] When a crosslinking agent is blended, the content of the crosslinking agent in the liquid crystal aligning agent is preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, relative to 100 parts by mass of the total amount of polymer components in the liquid crystal aligning agent. Furthermore, from the viewpoint of suppressing performance degradation due to the addition of an excessive amount, the content of the crosslinking agent is preferably 40 parts by mass or less, more preferably 30 parts by mass or less, relative to 100 parts by mass of the total amount of polymer components in the liquid crystal aligning agent. The crosslinking agent may be used alone or in combination of two or more.

[0096] (solvent) The liquid crystal aligning agent is usually prepared as a liquid composition in which the polymer (P) and other components used as needed are preferably dispersed or dissolved in a suitable solvent.

[0097] Examples of the organic solvent to be used include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 1,2-dimethyl-2-imidazolidinone, γ-butyrolactone, γ-butyrolactam, N,N-dimethylformamide, N,N-dimethylacetamide, 4-hydroxy-4-methyl-2-pentanone (diacetone alcohol), ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n-propyl ether, and ethylene glycol-i-propyl ether. 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, diisopentyl ether, ethylene carbonate, propylene carbonate, etc. These can be used alone or in combination of two or more.

[0098] In addition to the above, other components include, for example, functional silane compounds, polyfunctional (meth)acrylates, antioxidants, metal chelate compounds, curing accelerators, surfactants, fillers, dispersants, photosensitizers, etc. The blending ratio of the other components can be appropriately selected depending on each compound within a range that does not impair the effects of the present disclosure.

[0099] The solids concentration in the liquid crystal aligning agent (the ratio of the total mass of the components other than the solvent of the liquid crystal aligning agent to the total mass of the liquid crystal aligning agent) is appropriately selected taking into consideration viscosity, volatility, etc., but is preferably in the range of 1 to 10 mass%. That is, the liquid crystal aligning agent is applied to the surface of a substrate as described below, and preferably heated to form a coating film that is a liquid crystal alignment film or a coating film that will become a liquid crystal alignment film. In this case, a solids concentration of 1 mass% or more is preferable because it ensures a sufficient thickness of the coating film and makes it easy to obtain a good liquid crystal alignment film. Furthermore, a solids concentration of 10 mass% or less allows the coating film to have an unduly thick thickness, thereby making it possible to obtain a good liquid crystal alignment film, and also ensures an appropriate viscosity of the liquid crystal aligning agent, resulting in good applicability.

[0100] According to the present disclosure described above, the following liquid crystal aligning agent is provided. <Means 1> A liquid crystal aligning agent containing a polymer (P) having a partial structure represented by the above formula (1). <Means 2> The liquid crystal aligning agent according to <Means 1>, wherein the polymer (P) is at least one selected from the group consisting of polyamic acid, polyimide, polyamic acid ester, polyamide, polyorganosiloxane, and addition polymer. <Means 3> The liquid crystal aligning agent according to <Means 1> or <Means 2>, wherein the polymer (P) contains a structural unit derived from a diamine having a partial structure represented by the above formula (1). <Means 4> The liquid crystal aligning agent according to claim 3, wherein the diamine is at least one selected from the group consisting of compounds represented by the above formula (2-1) and compounds represented by the above formula (2-2). <Means 5> The liquid crystal aligning agent according to any one of <Means 1> to <Means 4>, further comprising a polymer not having the partial structure represented by the above formula (1). <Means 6> The liquid crystal aligning agent according to any one of <Means 1> to <Means 5>, wherein the polymer (P) contains a structural unit derived from a monomer having at least one partial structure selected from the group consisting of a nitrogen-containing heterocycle, an amino group, a protected amino group, an amide group, a protected amide group, a urea group, and a protected urea group. <Means 7> The liquid crystal aligning agent according to any one of <Means 1> to <Means 6>, wherein the polymer (P) has at least one selected from the group consisting of an alkyl group having 4 to 30 carbon atoms, a halogenated alkyl group having 4 to 30 carbon atoms, an alkoxy group having 4 to 30 carbon atoms, a halogenated alkoxy group having 4 to 30 carbon atoms, a group having a polycyclic structure in which two or more rings are bonded directly or via a divalent linking group, and a group having a steroid skeleton, in a side chain, and contains a structural unit derived from a monomer not having a partial structure represented by the above formula (1).

[0101] <Liquid crystal alignment film and liquid crystal element> The liquid crystal alignment film of the present disclosure is formed using the liquid crystal alignment agent prepared as described above. Furthermore, the liquid crystal element of the present disclosure includes a liquid crystal alignment film formed using the liquid crystal alignment agent described above. The operation mode of the liquid crystal in the liquid crystal element is not particularly limited, and various modes such as TN (Twisted Nematic), STN (Super Twisted Nematic), VA (Vertical Alignment) (including VA-MVA, VA-PVA, etc.), IPS (In-Plane Switching), FFS (Fringe Field Switching), OCB (Optically Compensated Bend), and PSA (Polymer Sustained Alignment) can be applied. The liquid crystal element can be manufactured, for example, by a method including the following steps 1 to 3. In step 1, different substrates are used depending on the desired operation mode. Steps 2 and 3 are common to all operation modes.

[0102] (Step 1: Formation of coating film) First, a liquid crystal alignment agent is applied to a substrate, and the coated surface is preferably heated to form a coating film on the substrate. Examples of substrates that can be used include transparent substrates made of glass, such as float glass or soda glass; or plastics, such as polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polycarbonate, and poly(alicyclic olefin). Examples of transparent conductive films that can be provided on one side of the substrate include NESA films (registered trademarks of PPG, Inc., USA) made of tin oxide (SnO2) and ITO films made of indium oxide-tin oxide (In2O3-SnO2). When manufacturing TN, STN, or VA liquid crystal devices, two substrates with patterned transparent conductive films are used. On the other hand, when manufacturing IPS or FFS liquid crystal devices, one substrate is provided with electrodes made of a comb-shaped patterned transparent conductive film or metal film, and another substrate with no electrodes is used. Examples of metal films that can be used include films made of metals such as chromium. The liquid crystal alignment agent is applied to the substrate on the electrode-forming surface, preferably by offset printing, spin coating, roll coating, or inkjet printing.

[0103] After the liquid crystal aligning agent is applied, preliminary heating (pre-baking) is preferably carried out for the purpose of preventing dripping of the applied liquid crystal aligning agent, etc. The pre-baking temperature is preferably 30 to 150° C., more preferably 40 to 120° C. The pre-baking time is preferably 0.25 to 10 minutes.

[0104] Thereafter, the solvent is further removed, and a baking (post-baking) step is carried out, if necessary, to thermally imidize the amic acid structure present in the polymer. The baking temperature (post-baking temperature) at this time is preferably 250°C or lower, more preferably 230°C or lower, and even more preferably 180°C or lower, from the viewpoints of suppressing deterioration such as discoloration due to high temperatures when forming a liquid crystal alignment film on a color filter and reducing environmental impact. Furthermore, from the viewpoint of suppressing deterioration of liquid crystal alignment properties and reliability due to the influence of solvent components remaining in the film, the post-baking temperature is preferably 80°C or higher, more preferably 120°C or higher. The post-baking time is preferably 5 to 150 minutes. The film thickness of the film thus formed is preferably 0.001 to 1 μm. After applying the liquid crystal alignment agent to a substrate, the organic solvent is removed to form a liquid crystal alignment film or a coating film that will become a liquid crystal alignment film.

[0105] (Step 2: Alignment treatment) When producing a TN-, STN-, IPS-, or FFS-type liquid crystal display device, the coating film formed in step 1 above is subjected to a treatment (alignment treatment) to impart liquid crystal alignment ability. This imparts the ability to align liquid crystal molecules to the coating film, turning it into a liquid crystal alignment film. The alignment treatment is preferably a rubbing treatment in which the surface of the coating film formed on the substrate is rubbed with cotton or the like, or a photo-alignment treatment in which the coating film is irradiated with light to impart liquid crystal alignment ability. When producing a vertical alignment-type liquid crystal display device, the coating film formed in step 1 above may be used as a liquid crystal alignment film as is, or the coating film may be subjected to an alignment treatment to further enhance the liquid crystal alignment ability. A liquid crystal alignment film suitable for a vertical alignment-type liquid crystal display device can also be suitably used for a PSA-type liquid crystal display device.

[0106] The light irradiation in the photo-alignment treatment can be performed by irradiating the coating film after the post-bake step, irradiating the coating film after the pre-bake step but before the post-bake step, or irradiating the coating film while it is being heated in at least one of the pre-bake and post-bake steps. In the photo-alignment treatment, the radiation to be irradiated to the coating film can be, for example, ultraviolet light and visible light containing light with a wavelength of 150 to 800 nm. Preferably, ultraviolet light containing light with a wavelength of 200 to 400 nm is used. When the radiation is polarized, it may be linearly polarized or partially polarized. Furthermore, when the radiation used is linearly polarized or partially polarized, irradiation may be performed from a direction perpendicular to the substrate surface, from an oblique direction, or a combination of these. When irradiating with unpolarized radiation, the irradiation direction is an oblique direction.

[0107] Examples of light sources that can be used include low-pressure mercury lamps, high-pressure mercury lamps, deuterium lamps, metal halide lamps, argon resonance lamps, xenon lamps, and excimer lasers. The radiation dose is preferably 400 to 20,000 J / m 2 and more preferably 1,000 to 5,000 J / m 2 The coating film may be irradiated with light while being heated in order to enhance reactivity. The method may further include a step of contacting the organic film that has been subjected to the light irradiation treatment with water, a water-soluble organic solvent, or a mixed solvent of water and a water-soluble organic solvent.

[0108] (Step 3: Construction of liquid crystal cell) Two substrates with liquid crystal alignment films formed thereon are prepared as described above, and a liquid crystal cell is fabricated by disposing a liquid crystal between the two opposing substrates. Examples of methods for fabricating a liquid crystal cell include (1) placing the two substrates opposite each other with a spacer between them so that the liquid crystal alignment films face each other, bonding the peripheries of the two substrates together with a sealant, injecting liquid crystal into the cell gap defined by the substrate surfaces and the sealant, and sealing the injection hole; and (2) applying a sealant to a predetermined location on one substrate with a liquid crystal alignment film, dropping liquid crystal at several predetermined locations on the liquid crystal alignment film, and then bonding the other substrate so that the liquid crystal alignment films face each other, while spreading the liquid crystal over the entire surface of the substrate (ODF method). The fabricated liquid crystal cell is preferably further heated to a temperature at which the liquid crystal used assumes an isotropic phase and then slowly cooled to room temperature to remove flow alignment that occurs during liquid crystal filling.

[0109] The sealing agent may be, for example, an epoxy resin containing a curing agent and aluminum oxide spheres as spacers, such as photospacers and bead spacers.

[0110] Examples of the liquid crystal to be used include nematic liquid crystals and smectic liquid crystals, with nematic liquid crystals being preferred. Examples of nematic liquid crystals that can be used include Schiff base liquid crystals, azoxy liquid crystals, biphenyl liquid crystals, phenylcyclohexane liquid crystals, ester liquid crystals, terphenyl liquid crystals, biphenylcyclohexane liquid crystals, pyrimidine liquid crystals, dioxane liquid crystals, bicyclooctane liquid crystals, and cubane liquid crystals. These liquid crystals may also be used by adding, for example, cholesteric liquid crystals, chiral agents, ferroelectric liquid crystals, etc.

[0111] One embodiment of the method for producing a liquid crystal element according to the present disclosure includes the following steps [A] to [C]. [A] A step of applying the liquid crystal aligning agent of the present disclosure onto each conductive film of a pair of substrates having a conductive film to form a coating film. [B] A step of constructing a liquid crystal cell by arranging a pair of substrates on which coating films have been formed so that the coating films face each other via a liquid crystal layer. [C] A step of irradiating the liquid crystal cell with light while a voltage is applied between the conductive films.

[0112] For example, in the PSA mode, a polymerizable compound (such as a polyfunctional (meth)acrylate compound) is filled into the cell gap together with the liquid crystal, and after the liquid crystal cell is constructed, the liquid crystal cell is irradiated with light while a voltage is applied between the conductive films of the pair of substrates. In manufacturing a PSA mode liquid crystal element, the proportion of the polymerizable compound used is, for example, 0.01 to 3 parts by mass, preferably 0.1 to 1 part by mass, per 100 parts by mass of the total liquid crystal.

[0113] Next, if necessary, a polarizing plate is attached to the outer surface of the liquid crystal cell. Examples of polarizing plates include a polarizing film called an "H film" made by stretching and aligning polyvinyl alcohol and absorbing iodine, sandwiched between cellulose acetate protective films, or a polarizing plate made of the H film itself. This produces a liquid crystal device.

[0114] The liquid crystal element of the present disclosure can be effectively applied to various applications. Specifically, it can be used in various display devices such as watches, portable game machines, word processors, notebook computers, car navigation systems, camcorders, PDAs, digital cameras, mobile phones, smartphones, various monitors, liquid crystal televisions, and information displays, as well as light control films. Furthermore, a liquid crystal element formed using the liquid crystal aligning agent of the present disclosure can also be applied to optical films such as retardation films. [Example]

[0115] The present disclosure will be explained in more detail below using examples, but the contents of the present disclosure are not limited to the following examples.

[0116] In the following examples, the weight average molecular weight (Mw), number average molecular weight (Mn) and molecular weight distribution (Mw / Mn) of the polymer, the imidization rate of the polyimide, and the solution viscosity of the polymer solution were measured by the following methods. <Weight average molecular weight, number average molecular weight and molecular weight distribution> Mw and Mn were measured by gel permeation chromatography (GPC) under the following conditions. The molecular weight distribution (Mw / Mn) was calculated from the obtained Mw and Mn. Equipment: Showa Denko "GPC-101" GPC column: Shimadzu GLC's "GPC-KF-801", "GPC-KF-802", "GPC-KF-803" and "GPC-KF-804" Mobile phase: tetrahydrofuran (THF) Column temperature: 40℃ Flow rate: 1.0mL / min Sample concentration: 1.0% by mass Sample injection volume: 100 μL Detector: differential refractometer Standard material: monodisperse polystyrene

[0117] <Imidization rate of polyimide> The imidized polymer was dried under reduced pressure at room temperature, then dissolved in deuterated dimethyl sulfoxide and measured at room temperature using tetramethylsilane as a reference substance. 1 H-NMR was measured and the value was calculated using the following mathematical formula (I). Imidization rate (%) = (1 - (A 1 / (A 2 ×α)))×100 …(I) (In formula (I), A 1 is the peak area due to the proton of the NH group that appears at a chemical shift of around 10 ppm, and A 2 is the peak area due to other protons, and α is the ratio of the number of other protons to one proton of the NH group in the polymer precursor (polyamic acid). <Solution viscosity of polymer solution> The solution viscosity (mPa·s) of the polymer solution was measured at 25°C using an E-type rotational viscometer.

[0118] The compounds used in the following examples are shown below. For convenience, hereinafter, the "compound represented by formula (X)" may be simply referred to as "compound (X)".

[0119] (Tetracarboxylic acid dianhydride) [ka]

[0120] (specific diamine) [ka]

[0121] (Other diamines) [ka] [ka] [ka] [ka]

[0122] (unsaturated monomer) [ka]

[0123] (additives) [ka]

[0124] <Monomer synthesis> [Synthesis Example 1-1: Synthesis of Compound (M-1)] Compound (M-1) was synthesized according to the following scheme. [ka]

[0125] 10.00 g of 2,5-dihydroxyacetophenone, 11.12 g of pyrrolidine, and 23.21 g of acetone were dissolved in 100 mL of acetonitrile and reacted at 45°C for 10 hours. After the reaction, 100 mL of ethyl acetate was added, and the mixture was separated twice with 100 mL of 1N hydrochloric acid and twice with 100 mL of water. The organic layer was concentrated using an evaporator, and then hexane was added and thermally recrystallized. The resulting solid was filtered, washed with 2-propanol, and dried under vacuum to obtain compound (M-1-1) 10.1. Next, 50 mL of tetrahydrofuran was added to 4.00 g of compound (M-1-1) and 4.96 g of 3,5-dinitrobenzyl chloride, and the mixture was heated to 40°C. A solution of 1.00 g of sodium hydroxide dissolved in 35 mL of distilled water was added dropwise, and the mixture was allowed to react at room temperature for 12 hours after the addition. After the reaction, the reaction solution was poured into 500 mL of distilled water, and the precipitated solid was filtered and washed with 2-propanol. The mixture was then vacuum dried and recrystallized to obtain 6.9 g of compound (M-1-2). 5.0 g of compound (M-1-2), 0.86 g of 5% palladium carbon, 30 mL of tetrahydrofuran, and 30 mL of ethanol were added and heated to 80°C. 4.03 g of hydrazine monohydrate was added dropwise, and the mixture was heated to reflux for 6 hours. After cooling to room temperature, the filtered reaction solution was reprecipitated in 600 mL of distilled water. The resulting solid was filtered, washed with water, and then vacuum dried to obtain 3.8 g of compound (M-1).

[0126] [Synthesis Example 1-2: Synthesis of Compound (M-2)] Compound (M-2) was synthesized according to the following scheme. [ka]

[0127] Compound (M-2-1) was synthesized according to the method described in "Bioorg. Med. Chem. Lett. 1999, 9, 2773-2778" to obtain 6.5 g. Next, 5.0 g of compound (M-2-1) and 3.70 g of triethylamine were dissolved in 30 mL of N,N-dimethylformamide. A solution of 5.95 g of 2,4-dinitrofluorobenzene dissolved in 20 mL of N,N-dimethylformamide was added dropwise, and the mixture was allowed to react at room temperature for 8 hours. After the reaction, the reaction solution was reprecipitated with 400 mL of distilled water. The resulting solid was filtered, washed with water and ethanol, and then vacuum-dried to obtain 9.1 g of compound (M-2-2). 7.0 g of compound (M-2-2), 1.35 g of 5% palladium carbon, 45 mL of tetrahydrofuran, and 45 mL of ethanol were added and heated to 80 °C. 6.37 g of hydrazine monohydrate was added dropwise, and the mixture was heated to reflux for 6 hours. After cooling to room temperature, the filtered reaction solution was reprecipitated with 900 mL of distilled water. The resulting solid was filtered, washed with water, and then vacuum dried to obtain 5.8 g of compound (M-2).

[0128] [Synthesis Example 1-3: Synthesis of Compound (M-3)] Compound (M-3) was synthesized according to the following scheme. [ka]

[0129] 10.00 g of 2,5-dihydroxyacetophenone, 11.12 g of pyrrolidine, and 28.44 g of butyraldehyde were dissolved in 100 mL of acetonitrile and reacted at 45°C for 10 hours. After the reaction, 100 mL of ethyl acetate was added, and the mixture was separated twice with 100 mL of 1N hydrochloric acid and twice with 100 mL of water. The organic layer was concentrated using an evaporator, and then hexane was added and thermally recrystallized. The resulting solid was filtered, washed with 2-propanol, and dried under vacuum to obtain 10.8 g of compound (M-3-1). Next, 7.00 g of compound (M-3-1) and 6.87 g of triethylamine were dissolved in 120 mL of tetrahydrofuran and cooled to 0°C on ice. A solution of 7.83 g of 3,5-dinitrobenzoyl chloride in 80 mL of tetrahydrofuran was added dropwise thereto, and the mixture was allowed to react at room temperature for 12 hours. After the reaction, the reaction solution was reprecipitated with 900 mL of distilled water. The resulting solid was filtered, washed with water and 2-propanol, and then vacuum-dried to obtain 11.1 g of compound (M-3-2). 50 mL of tetrahydrofuran and 50 mL of ethanol were added to 10.0 g of compound (M-3-2) and 1.59 g of 5% palladium carbon. After replacing the atmosphere in the reaction vessel with hydrogen, the reaction was carried out at room temperature for 12 hours. After cooling to room temperature, the filtered reaction solution was reprecipitated in 1000 mL of distilled water. The resulting solid was filtered, washed with water, and then vacuum dried to obtain 7.7 g of compound (M-3).

[0130] [Synthesis Example 1-4: Synthesis of Compound (M-4)] Compound (M-4) was synthesized according to the following scheme. [ka]

[0131] Compound (M-4-1) was synthesized according to the method described in "Macromolecules 2003, 36, 4385-4396" and 5.2 g was obtained. Next, 5.00 g of compound (M-4-1) and 9 mL of thionyl chloride were added with 2 drops of N,N-dimethylformamide and reacted at 80 °C for 2 hours. After the reaction, thionyl chloride was removed under reduced pressure to obtain 5.2 g of compound (M-4-2). 4.8 g of compound (M-4) was obtained by the same method as in Synthesis Example 1-3, except that compound (M-4-2) and compound (M-4-3) were used instead of 3,5-dinitrobenzoyl chloride and compound (M-3-1), respectively.

[0132] [Synthesis Example 1-5: Synthesis of Compound (M-5)] Compound (M-5) was synthesized according to the following scheme. [ka]

[0133] Compound (M-5-1) was synthesized according to the method described in "Can. J. Chem., 1985, 63, 2589-2596" to obtain 6.1 g. Next, 5.00 g of (2,4-dinitrophenyl)-acetic acid and 16 mL of thionyl chloride were added with 2 drops of N,N-dimethylformamide, and the mixture was reacted at 80°C for 2 hours. After the reaction, thionyl chloride was removed under reduced pressure to obtain 5.0 g of compound (M-5-2). 5.3 g of compound (M-5) was obtained by the same method as in Synthesis Example 1-3, except that compound (M-5-2) and compound (M-5-1) were used instead of 3,5-dinitrobenzoyl chloride and compound (M-3-1), respectively.

[0134] [Synthesis Example 1-6: Synthesis of Compound (M-6)] Compound (M-6) was synthesized according to the following scheme. [ka]

[0135] 5.00 g of compound (M-1-1) was dissolved in 50 mL of tetrahydrofuran, followed by the addition of 3.92 g of potassium carbonate and 2.96 g of 2-bromoethanol. The mixture was heated to reflux for 12 hours. After cooling to room temperature, the solvent was removed using a rotary evaporator. 50 mL of ethyl acetate and 50 mL of 2N sodium hydroxide were added and stirred at room temperature for 1 hour. Purification was performed twice with 1N hydrochloric acid and twice with water. The separated organic layer was evaporated under reduced pressure and dried to obtain 4.3 g of compound (M-6-1). Next, 4.0 g of compound (M-6-1) and 2.1 g of triethylamine were dissolved in 40 mL of tetrahydrofuran. A solution of 3.31 g of 2,4-dinitrofluorobenzene dissolved in 40 mL of tetrahydrofuran was added dropwise, and the mixture was allowed to react at room temperature for 8 hours. After the reaction, the reaction solution was reprecipitated with 800 mL of distilled water. The resulting solid was filtered, washed with water and ethanol, and then vacuum-dried to obtain 5.1 g of compound (M-6-2). 5.0 g of compound (M-6-2), 0.79 g of 5% palladium carbon, 25 mL of tetrahydrofuran, and 25 mL of ethanol were added and heated to 80 °C. 3.73 g of hydrazine monohydrate was added dropwise, and the mixture was heated to reflux for 6 hours. After cooling to room temperature, the filtered reaction solution was reprecipitated with 500 mL of distilled water. The resulting solid was filtered, washed with water, and then vacuum dried to obtain 3.7 g of compound (M-6).

[0136] [Synthesis Example 1-7: Synthesis of Compound (M-7)] Compound (M-7) was synthesized according to the following scheme. [ka]

[0137] Compound (M-7-1) was synthesized according to the method described in "Tetrahedron Lett. 2001, 42, 4001-4003" to obtain 6.4 g. Next, 5.00 g of compound (M-7-1) was dissolved in 50 mL of tetrahydrofuran, and then 3.92 g of potassium carbonate and 3.62 g of 4-bromo-1-butanol were added, followed by heating under reflux for 12 hours. After cooling to room temperature, the solvent was removed using a rotary evaporator. 50 mL of ethyl acetate and 50 mL of 2N sodium hydroxide were added thereto, and the mixture was stirred at room temperature for 1 hour. After that, separation and purification were performed twice with 1N hydrochloric acid and twice with water. The separated organic layer was evaporated under reduced pressure and dried to obtain 4.8 g of compound (M-7-2). 4.8 g of compound (M-7) was obtained in the same manner as in Synthesis Example 1-3, except that compound (M-7-2) was used instead of compound (M-3-1).

[0138] [Synthesis Example 1-8: Synthesis of Compound (M-8)] Compound (M-8) was synthesized according to the following scheme. [ka]

[0139] 10.00 g of 2,5-dihydroxyacetophenone, 11.12 g of pyrrolidine, and 38.70 g of cyclohexanone were dissolved in 100 mL of acetonitrile and reacted at 45°C for 10 hours. After the reaction, 100 mL of ethyl acetate was added, and the mixture was separated twice with 100 mL of 1N hydrochloric acid and twice with 100 mL of water. The organic layer was concentrated using an evaporator, and then hexane was added and thermally recrystallized. The resulting solid was filtered, washed with 2-propanol, and dried under vacuum to obtain 12.3 g of compound (M-8-1). 5.3 g of compound (M-8) was obtained in the same manner as in Synthesis Example 1-3, except that compound (M-8-1) was used instead of compound (M-3-1).

[0140] [Synthesis Example 1-9: Synthesis of Compound (M-9)] Compound (M-9) was synthesized according to the following scheme. [ka]

[0141] 10.00 g of 2,5-dihydroxyacetophenone, 11.12 g of pyrrolidine, and 45.0 g of heptanal were dissolved in 100 mL of acetonitrile and reacted at 45°C for 10 hours. After the reaction, 100 mL of ethyl acetate was added, and the mixture was separated twice with 100 mL of 1N hydrochloric acid and twice with 100 mL of water. The organic layer was concentrated using an evaporator, and then hexane was added and thermally recrystallized. The resulting solid was filtered, washed with 2-propanol, and dried under vacuum to obtain 12.7 g of compound (M-9-1). 5.8 g of compound (M-9) was obtained in the same manner as in Synthesis Example 1-3, except that compound (M-9-1) was used instead of compound (M-3-1).

[0142] [Synthesis Example 1-10: Synthesis of Compound (M-10)] Compound (M-10) was synthesized according to the following scheme. [ka]

[0143] 4.17 g of 4-(chloromethyl)styrene, 5.00 g of compound (M-1-1), and 9.0 g of potassium carbonate were dissolved in 80 mL of dimethylformamide and reacted at 60°C for 12 hours. After the reaction was completed, the reaction solution was added dropwise to 800 mL of distilled water, and the resulting solid was filtered. The resulting solid was then recrystallized using THF solvent, and filtered and dried to obtain 6.7 g of compound (M-10).

[0144] [Synthesis Example 1-11: Synthesis of Compound (M-11)] Compound (M-11) was synthesized according to the following scheme. [ka]

[0145] 7.00 g of 2,5-dihydroxyacetophenone, 7.79 g of pyrrolidine, and 8.82 g of 4-phenylcyclohexanone were dissolved in 50 mL of N,N-dimethylformamide and reacted at 100°C for 24 hours. After the reaction, 200 mL of ethyl acetate was added, and the mixture was separated twice with 100 mL of 1N hydrochloric acid and twice with 100 mL of water. The organic layer was concentrated using an evaporator, and then hexane was added and thermally recrystallized. The resulting solid was filtered, washed with 2-propanol, and dried under vacuum to obtain compound (M-11-1). 7.5 g of compound (M-11) was obtained in the same manner as in Synthesis Example 1-10, except that compound (M-11-1) was replaced with compound (M-11-1).

[0146] <Polymer synthesis> 1. Polyimide Synthesis [Synthesis Example 2-1] 100 moles of compound (TA-1) as a tetracarboxylic dianhydride, and 10 moles of compound (DA-4), 40 moles of compound (DA-7), 20 moles of compound (DA-8), and 30 moles of compound (M-1) as diamines were dissolved in 170 g of N-methyl-2-pyrrolidone (NMP) and reacted at 40 °C for 24 hours to obtain a solution containing 20 mass% polyamic acid. Next, NMP was added to the resulting polyamic acid solution, and pyridine and acetic anhydride were added in amounts of 1.8 molar equivalents relative to the carboxyl groups derived from the tetracarboxylic dianhydride of the polyamic acid, and a dehydration ring-closing reaction was carried out at 80 °C for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with fresh NMP and further concentrated to obtain a solution containing 15 mass% polyimide with an imidization rate of 70% (referred to as polymer (PI-1)). A small amount of this solution was taken and NMP was added to make a 10% by mass solution, and the viscosity of the solution was measured to be 42 mPa·s. The resulting polymer solution was then poured into a large excess of methanol to precipitate the reaction product, which was then washed with methanol and dried under reduced pressure at 40°C for 15 hours to obtain polymer (PI-1).

[0147] [Synthesis Examples 2-3 to 2-10, 2-12 to 2-15] Polymerization was carried out in the same manner as in Synthesis Example 2-1, except that the types and amounts of tetracarboxylic dianhydrides and diamines used in polymerization were changed as shown in Table 1, to obtain polyimide polymers (PI-2) to (PI-10) and (PI-12) to (PI-15). In Table 1, the values ​​for tetracarboxylic dianhydrides represent the ratio (parts by mole) of each compound relative to 100 parts by mole of the total amount of tetracarboxylic dianhydrides used in the synthesis. The values ​​for diamines represent the ratio (parts by mole) of each compound relative to 100 parts by mole of the total amount of diamines used in the synthesis.

[0148] 2. Synthesis of polyamic acid [Synthesis Example 2-2] 100 parts by mole of compound (TA-1) as a tetracarboxylic dianhydride, 50 parts by mole of compound (DA-3), 20 parts by mole of compound (DA-7), and 30 parts by mole of compound (M-2) as diamines were dissolved in 170 g of NMP and reacted at 60°C for 8 hours to obtain a solution containing 20% ​​by mass of polymer (PI-2), a polyamic acid. The viscosity of this solution was 39 mPa s.

[0149] [Synthesis Examples 2-11, 2-16 to 2-19] Polymerization was carried out in the same manner as in Synthesis Example 2-2, except that the types and amounts of tetracarboxylic dianhydrides and diamines used in polymerization were changed as shown in Table 1, to obtain polyamic acid polymers (PI-11), (PI-16) to (PI-19), respectively.

[0150] [Table 1]

[0151] 3. Synthesis of addition polymers [Synthesis Example 3-1] Under nitrogen, a 100 mL two-neck flask was charged with 30 mol parts of compound (E-1), 20 mol parts of compound (E-4), 20 mol parts of compound (E-5), and 30 mol parts of compound (M-10) as polymerization monomers, 2 mol parts of 2,2'-azobis(2,4-dimethylvaleronitrile) per 100 mol parts of polymerization monomers, and 50 mL of tetrahydrofuran as solvent. The polymerization reaction was carried out at 70 °C for 6 hours. The total number of moles of polymerization monomers was 50 mmol. After reprecipitation in n-hexane, the precipitate was filtered and dried in vacuum at room temperature for 8 hours to obtain the target polymer (ACR-1). The weight-average molecular weight (Mw) measured by GPC (polystyrene equivalent) was 47,700, and the molecular weight distribution (Mw / Mn) was 2.0.

[0152] [Synthesis Example 3-2] Polymerization was carried out in the same manner as in Synthesis Example 3-1, except that the types and molar ratios of the polymerizable monomers were changed as shown in Table 2, to obtain a polymer (ACR-2) having the same weight-average molecular weight and molecular weight distribution as the polymer (ACR-1). The total number of moles of the polymerizable monomers was 50 mmol, the same as in Synthesis Example 3-1. The values ​​in Table 2 represent the amount (mol %) of each monomer charged relative to the total monomers used in the synthesis of the polymer.

[0153] [Table 2]

[0154] 4. Synthesis of polyorganosiloxane [Synthesis Example 4-1] A 1000 ml three-neck flask was charged with 90.0 g of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 500 g of methyl isobutyl ketone, and 10.0 g of triethylamine and mixed at room temperature. Next, 100 g of deionized water was added dropwise from the dropping funnel over 30 minutes, and the mixture was stirred under reflux while reacting at 80°C for 6 hours. After the reaction was completed, the organic layer was removed and washed with a 0.2% by weight aqueous solution of ammonium nitrate until the water was neutral. The solvent and water were then distilled off under reduced pressure. An appropriate amount of methyl isobutyl ketone was added to obtain a 50% by weight solution of polymer (ESSQ-1), a polyorganosiloxane having epoxy groups. Into a 500 ml three-neck flask, 18.68 g of compound (C-1) (30 mol % relative to the amount of epoxy groups in polymer (ESSQ-1)), 4.00 g of tetrabutylammonium bromide, 80 g of a solution containing polymer (ESSQ-1), and 294 g of methyl isobutyl ketone were added and stirred at 90°C for 18 hours. After cooling to room temperature, a separation and washing operation with distilled water was repeated 10 times. Thereafter, the organic layer was recovered, concentrated using a rotary evaporator and diluted with NMP twice, and then adjusted using NMP so that the solid concentration became 10% by mass, thereby obtaining an NMP solution of polymer (PS-1). [ka]

[0155] <Preparation and Evaluation of Liquid Crystal Alignment Agent> [Example 1] (1) Preparation of liquid crystal alignment agent (AL-1) To 100 parts by mass of the polymer (PI-1) obtained in Synthesis Example 2-1, 5 parts by mass of the polymer (PS-1) obtained in Synthesis Example 4-1, 10 parts by mass of the compound (Add-1) as a crosslinker, and NMP and butyl cellosolve (BC) as solvents were added to obtain a solution with a solvent composition of NMP / BC = 50 / 50 (mass ratio) and a solids concentration of 4.0 mass%. This solution was filtered through a filter with a pore size of 0.2 μm to prepare a liquid crystal alignment agent (AL-1).

[0156] (2) Preparation of liquid crystal composition 5% by mass of a liquid crystal compound represented by the following formula (L1-1) and 0.3% by mass of a photopolymerizable compound represented by the following formula (L2-1) were added to 10 g of nematic liquid crystal (MLC-6608, manufactured by Merck) and mixed to obtain liquid crystal composition LC1. [ka]

[0157] (3) Manufacturing of PSA type liquid crystal display elements The liquid crystal alignment agent (AL-1) prepared above was applied to the electrode surfaces of two glass substrates, each having a conductive film consisting of a slit-patterned ITO electrode, using a liquid crystal alignment film printer (manufactured by Nissha Printing Co., Ltd.). The substrates were prebaked on a hot plate at 80°C for 2 minutes to remove the solvent, and then postbaked on a hot plate at 230°C for 30 minutes to form coatings with an average thickness of 100 nm. These coatings were ultrasonically cleaned in ultrapure water for 1 minute and then dried in a clean oven at 100°C for 10 minutes to obtain a pair (two substrates) with liquid crystal alignment films. The electrode pattern used was the same as the electrode pattern in the PSA mode. Next, an epoxy resin adhesive containing aluminum oxide spheres with a diameter of 5.5 μm was applied to the outer edge of the surface of one of the pair of substrates having a liquid crystal alignment film, and the substrates were then placed together with the liquid crystal alignment film surfaces facing each other and pressed together, and the adhesive was cured. Next, the liquid crystal composition LC1 prepared above was filled between the pair of substrates through the liquid crystal injection port, and the liquid crystal injection port was sealed with an acrylic photocurable adhesive to produce a liquid crystal cell. Then, an AC voltage of 10 V at a frequency of 60 Hz was applied between the conductive films of the liquid crystal cell, and while the liquid crystal was operating, an ultraviolet irradiation device using a metal halide lamp as a light source was used to irradiate the liquid crystal with 100,000 J / m. 2 The substrate was irradiated with ultraviolet light at an exposure dose of 1000 kJ / cm. Note that this exposure dose was measured using an actinometer measuring at a wavelength of 365 nm. Polarizing plates were then attached to both outer surfaces of the substrate so that their polarization directions were perpendicular to each other and formed a 45° angle with the projection direction of the optical axis of the ultraviolet light from the liquid crystal alignment film onto the substrate surface, thereby producing a PSA-type liquid crystal display element.

[0158] (4) Evaluation of pretilt angle For the liquid crystal display element manufactured in (2) above, the tilt angle of the liquid crystal molecules from the substrate surface was measured by a crystal rotation method using a He-Ne laser beam in accordance with the method described in non-patent document (TJ Scheffer et al. J. Appl. Phys. vol. 19, p. 2013 (1980)). The pretilt angle was defined as the tilt angle of the liquid crystal molecules from the substrate surface. In this case, a pretilt angle of 88.5 degrees or less was rated as "good (○)," a pretilt angle of more than 88.5 degrees but less than 89.0 degrees was rated as "fair (△)," and a pretilt angle of 89.0 degrees or more was rated as "poor (×)." As a result, this example was rated as "good (○)."

[0159] (5) Evaluation of narrow line adhesion The liquid crystal alignment agent (AL-1) was applied to a glass substrate using a spinner, prebaked on a hot plate at 80°C for 2 minutes, and then heated (post-baked) in a nitrogen-purged oven at 230°C for 30 minutes to form a coating film with an average thickness of 0.10 μm. By repeating the same procedure, two glass substrates with coating films were produced. On the coating film of one glass substrate with a coating film, an ODF sealant (S-WB42, manufactured by Sekisui Chemical Co., Ltd.) was applied to a width of 0.5 mm (i.e., a seal width of 0.5 mm), and the other glass substrate was bonded so that the coating film and the ODF sealant were in contact. Then, a metal halide lamp was used to apply 30,000 J / m 2 After irradiating the sample with light (equivalent to 365 nm), the sample was heated in an oven at 120°C for 1 hour. The narrow line adhesion was then evaluated by measuring the adhesion force using a tension and compression tester (model number: SDWS-0201-100SL) manufactured by Imada Seisakusho. The evaluation was conducted when the adhesion force was 175 N / cm. 2 If the adhesive strength is 160N / cm or more, it is considered to be "particularly good (◎)" 2 More than 175N / cm 2 If it was less than 150N / cm, it was rated as "Good (○)" 2 More than 160N / cm 2 If it is less than 150N / cm, it is "Fair (△)". 2 If the adhesive strength was less than 180 N / cm, it was rated as "poor (x)". 2 The narrow line adhesion was rated as "particularly good (A)".

[0160] (6) Evaluation of long-term thermal reliability A PSA-type liquid crystal cell was produced in the same manner as in (3) above, except that no polarizing plates were attached to either outer surface of the substrate. A voltage of 5 V was applied to this PSA-type liquid crystal cell for 60 microseconds over a span of 167 milliseconds, and the voltage holding ratio was measured 167 milliseconds after the application was stopped. A VHR-1 manufactured by Toyo Corporation was used as the measuring device. The resulting liquid crystal cell was then stored in a 100°C thermostatic chamber for 21 days (approximately 500 hours), after which the voltage retention ratio was measured again. The long-term thermal reliability of the liquid crystal cell (i.e., the reliability of being able to withstand long-term use in a high-temperature environment) was evaluated based on the decrease in voltage retention ratio due to storage in a 100°C thermostatic chamber (voltage retention ratio (%) after liquid crystal cell production - voltage retention ratio (%) after storage in the thermostatic chamber). The evaluation was as follows: "particularly good (◎)" if the decrease in voltage retention ratio was less than 15%, "good (○)" if it was 15% or more but less than 25%, "fair (△)" if it was 25% or more but less than 40%, and "poor (×)" if it was 40% or more. As a result, this example was evaluated as "good (○)."

[0161] (7) Evaluation of high temperature and humidity resistance The PSA-type liquid crystal display element manufactured by the method described in (3) above was stored in an oven set at 60°C and 90% humidity for 300 hours, and then the voltage holding ratio was measured in the same manner as described in (6) above. This value was designated VHR2, and the voltage holding ratio measured before storage under high-temperature, high-humidity conditions of 60°C and 90% humidity was designated VHR1. The decrease in voltage holding ratio, ΔVHR, was calculated by subtracting VHR1 from VHR2, and the high-temperature, high-humidity resistance was evaluated based on ΔVHR. A ΔVHR of less than 5% was designated "particularly good (◎)," a value of 5% to less than 10% was designated "good (○)," a value of 10% to less than 20% was designated "fair (△)," and a value of 20% or more was designated "poor (×)." As a result, in this example, the result was "particularly good (◎)."

[0162] [Examples 2 to 13 and Comparative Examples 1 to 4] Liquid crystal alignment agents (AL-2) to (AL-9) and (AR-1) to (AR-4) were prepared using the same solvent composition and solid content concentration as in Example 1, except that the blending composition was changed as shown in Table 3. Furthermore, using each liquid crystal alignment agent, PSA-type liquid crystal display elements were produced in the same manner as in Example 1, and various evaluations were carried out. The evaluation results are shown in Table 3. In Table 3, the parts of the polymer and crosslinking agent represent parts by mass.

[0163] [Table 3]

[0164] As can be seen from the results of the above examples, the liquid crystal aligning agents of Examples 1 to 13 containing the polymer (P) exhibited well-balanced improvements in pretilt angle characteristics, narrow line adhesion, long-term thermal reliability, and high-temperature and high-humidity resistance. 1 and R 2 In Examples 1 and 4 to 13, which used polymer (P) having a substituent group at 1, the resistance to high temperature and humidity was evaluated as "particularly good" and was excellent.

[0165] In contrast, Comparative Examples 1 to 4, which did not contain polymer (P), were inferior to Examples 1 to 13 in narrow line adhesion, long-term thermal reliability, and high-temperature, high-humidity resistance. Furthermore, Comparative Examples 3 and 4 also had inferior pretilt angle characteristics to Examples 1 to 13. The reason why Comparative Examples 1 to 3, which used polymers (PI-12), (PI-13), and (ACR-2) having a chromanone structure but different substituent groups instead of polymer (P) did not have sufficient narrow line adhesion, long-term thermal reliability, and high-temperature, high-humidity resistance is presumably because the polymers (PI-12), (PI-13), and (ACR-2) had larger side chain structures than the polymers (PI-1) to (PI-8), (PI-14) to (PI-17), and (ACR-1) used in Examples 1 to 13, resulted in reduced film density and side chain entanglement.

Claims

1. A liquid crystal aligning agent comprising a polymer (P) having a partial structure represented by the following formula (1): 【Chemistry 1】 (In formula (1), R １ and R ２ are each independently an alkyl group having 1 to 3 carbon atoms. １ represents a single bond, an alkanediyl group having 1 to 6 carbon atoms, —O—, —CH ２ -O-* １ , —O—(CH ２ ) ａ -O-, -(CH ２ ) ｂ -COO-* １ , -(CH ２ ) ｂ -COO-(CH ２ ) ａ -O-* １ or -O-CO-* １ a is an integer from 1 to 6. b is an integer from 0 to 6. * １ " represents a bond to the benzene ring in formula (1). "*" represents a bond.)

2. The liquid crystal aligning agent according to claim 1, wherein the polymer (P) is at least one selected from the group consisting of polyamic acid, polyimide, polyamic acid ester, polyamide, polyorganosiloxane and addition polymer.

3. The liquid crystal aligning agent according to claim 1 , wherein the polymer (P) contains a structural unit derived from a diamine having a partial structure represented by the formula (1).

4. The liquid crystal aligning agent according to claim 3, wherein the diamine is at least one selected from the group consisting of compounds represented by the following formula (2-1) and compounds represented by the following formula (2-2): 【Chemistry 2】 (In formula (2-1) and formula (2-2), Ar １ and Ar ３ are each independently a trivalent aromatic ring group. ２ and Ar ４ are each independently a divalent aromatic ring group. ２ and X ３ are each independently a single bond, —O—, or —CH ２ -, -CO-, -NR ３ -, -COO-, -OCO-, -CONR ３ -or-NR ３ CO-. R ３ is a hydrogen atom or a monovalent organic group. １ , R ２ and X １ has the same meaning as the above formula (1).

5. The liquid crystal aligning agent according to claim 1, further comprising a polymer not having the partial structure represented by the formula (1).

6. The polymer (P) comprises a structural unit derived from a monomer having at least one partial structure selected from the group consisting of a nitrogen-containing heterocycle, an amino group, a protected amino group, an amide group, a protected amide group, a urea group and a protected urea group. The liquid crystal aligning agent according to claim 1.

7. The polymer (P) has at least one selected from the group consisting of an alkyl group having 4 to 30 carbon atoms, a halogenated alkyl group having 4 to 30 carbon atoms, an alkoxy group having 4 to 30 carbon atoms, a halogenated alkoxy group having 4 to 30 carbon atoms, a group having a polycyclic structure in which two or more rings are bonded directly or through a divalent linking group, and a group having a steroid skeleton, in a side chain, and the liquid crystal aligning agent according to claim 1, comprising a structural unit derived from a monomer that does not have a partial structure represented by the above formula (1).

8. A liquid crystal alignment film formed using the liquid crystal aligning agent according to any one of claims 1 to 7.

9. A liquid crystal device comprising the liquid crystal alignment film according to claim 8.

10. A step of applying the liquid crystal aligning agent according to any one of claims 1 to 7 onto each conductive film of a pair of substrates having a conductive film to form a coating film; a step of constructing a liquid crystal cell by disposing a pair of substrates on which the coating film is formed so that the coating film faces each other via a liquid crystal layer; and irradiating the liquid crystal cell with light while applying a voltage between the conductive films.

11. A polymer having a partial structure represented by the following formula (1): 【Transformation 3】 (In formula (1), R １ and R ２ are each independently an alkyl group having 1 to 3 carbon atoms. １ represents a single bond, an alkanediyl group having 1 to 6 carbon atoms, —O—, —CH ２ -O-* １ , —O—(CH ２ ) ａ -O-, -(CH ２ ) ｂ -COO-* １ , -(CH ２ ) ｂ -COO-(CH ２ ) ａ -O-* １ or -O-CO-* １ a is an integer from 1 to 6. b is an integer from 0 to 6. * １ " represents a bond to the benzene ring in formula (1). "*" represents a bond.)

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