Liquid crystal aligning agent, liquid crystal alignment film, and liquid crystal display element

Abstract

Provided are: a liquid crystal aligning agent which can suppress coating defects such as uneven printing and pinholes and from which a liquid crystal alignment film having a sufficient thickness can be obtained; a liquid crystal alignment film; and a liquid crystal display element, and a method for manufacturing the same.　The liquid crystal aligning agent contains a component (C) and a polymer component (P) containing one or more polymers, wherein the polymer component (P) contains at least one polymer (P) selected from the group consisting of a polyimide precursor and a polyimide which is an imidized product of the polyimide precursor.　Component (C) is at least one compound selected from the group consisting of cyclic monoterpene compounds (compound (C)).

Description

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

[0001] The present invention relates to a liquid crystal aligning agent, a liquid crystal alignment film, and a liquid crystal display element.

[0002] A liquid crystal display element includes, for example, a liquid crystal layer sandwiched between an element substrate and a color filter substrate, pixel electrodes and a common electrode that apply an electric field to the liquid crystal layer, a liquid crystal alignment film that controls the orientation of liquid crystal molecules in the liquid crystal layer, thin film transistors (TFTs) that switch electric signals supplied to the pixel electrodes, etc. Known methods for driving liquid crystal molecules include vertical electric field methods such as the TN (Twisted Nematic) method and the VA (Vertical Alignment) method, and horizontal electric field methods such as the IPS (In-Plane Switching) method and the FFS (Fringe Field Switching) method.

[0003] A liquid crystal alignment agent, which is a material for forming a liquid crystal alignment film, is a polymer component dissolved in a solvent, and the liquid crystal alignment film is formed by applying the liquid crystal alignment agent to a substrate and heating it. Here, the polymer component is typically a polymer such as polyamic acid, polyamic acid ester, and / or a polyimide obtained by imidizing these. Furthermore, as a solvent for the liquid crystal alignment agent, organic solvents in which the polymer is highly soluble, such as aprotic polar solvents such as N-methyl-2-pyrrolidone and γ-butyrolactone, and solvents such as butyl cellosolve, which are used to improve the coatability of the liquid crystal alignment agent, are generally used (see, for example, Patent Document 1).

[0004] Japanese Patent Application Publication No. 2020-86438

[0005] In recent years, large-screen, high-resolution liquid crystal display elements have become mainstream, and standards for display elements with increased pixel counts, such as 4K and 8K, have been established. Liquid crystal alignment films are therefore required to have good step coverage for the surface steps of the TFT substrate. Poor step coverage can lead to display defects due to poor alignment of liquid crystal molecules and insufficient adsorption of impurities. Therefore, increasing the thickness of the liquid crystal alignment film is considered as a way to improve step coverage. However, the inventors' investigations revealed that a liquid crystal alignment agent that increases the thickness of the liquid crystal alignment film also increases the viscosity of the liquid crystal alignment agent, resulting in coating defects such as uneven printing and pinholes.

[0006] In view of the above, an object of the present invention is to provide a liquid crystal alignment agent that can suppress coating defects such as printing unevenness and pinholes and can obtain a liquid crystal alignment film having a sufficient thickness, a liquid crystal alignment film obtained from the liquid crystal alignment agent, and a liquid crystal display element.

[0007] As a result of intensive research into achieving the above-mentioned object, the present inventors have found that using a liquid crystal aligning agent containing a polymer component (P) containing one or more types of polymers and a specific compound component is extremely effective for achieving the above-mentioned object, and have completed the present invention.

[0008] The present invention encompasses the following aspects: A liquid crystal aligning agent containing a polymer component (P) containing one or more polymers, and a component (C), wherein the polymer component (P) contains at least one polymer (P) selected from the group consisting of polyimide precursors and polyimides that are imidized products of the polyimide precursors. Component (C): one or more compounds selected from the group consisting of cyclic monoterpene compounds (compounds (C)). Throughout this specification, the following terms and abbreviations have the following meanings: A halogen atom is a fluorine atom, chlorine atom, bromine atom, iodine atom, etc. In both cases, * represents a bond. Furthermore, Boc represents a tert-butoxycarbonyl group, and Fmoc represents a 9-fluorenylmethoxycarbonyl group.

[0009] According to the present invention, a liquid crystal aligning agent capable of suppressing coating defects such as printing unevenness and pinholes and obtaining a liquid crystal alignment film having sufficient thickness, a liquid crystal alignment film obtained from the liquid crystal aligning agent, and a liquid crystal display element can be obtained. Therefore, a liquid crystal alignment film having the configuration of the present invention can suppress, for example, the elution of impurities from the electrode substrate and color filter substrate into the liquid crystal layer, thereby providing a liquid crystal display element with excellent image retention and reliability. The mechanism by which the above-mentioned effects of the present invention are achieved is not entirely clear, but is roughly presumed to be as follows. The cyclic monoterpenes disclosed in the present invention have a hydrophobic structure, which is thought to weaken the intermolecular interactions between polymers. Therefore, it is thought that the fluidity of the liquid crystal aligning agent can be increased, resulting in the above-mentioned effects.

[0010] <Polymer component (P)> The polymer component (P) contained in the liquid crystal aligning agent of the present invention contains at least one polymer (P) selected from the group consisting of polyimide precursors and polyimides which are imidized products of the polyimide precursors. The polymer (P) has, for example, one or more structural units, and may have an embodiment having at least one structural unit selected from the group consisting of a structural unit (p0) represented by the following formula (P0) and an imidized structural unit of the structural unit (p0): (In formula (P0), X represents a tetravalent organic group, Y represents a divalent organic group, R and Z each independently represent a hydrogen atom or a monovalent organic group, and multiple R and Z each independently have the above definition.)

[0011] X in the formula (P0) represents a tetravalent organic group, preferably a tetravalent tetracarboxylic acid residue. Here, the tetravalent tetracarboxylic acid residue may be, for example, a tetravalent organic group present among four carbonyl groups of a tetracarboxylic acid dianhydride or a derivative thereof (e.g., a tetracarboxylic acid, a tetracarboxylic acid dihalide, a tetracarboxylic acid dialkyl ester, or a tetracarboxylic acid dialkyl ester dihalide). From the viewpoint of optimally achieving the effects of the present invention, X is preferably a tetravalent tetracarboxylic acid residue derived from an acyclic aliphatic tetracarboxylic acid dianhydride, an alicyclic tetracarboxylic acid dianhydride, an aromatic tetracarboxylic acid dianhydride, or a derivative thereof. The tetracarboxylic acid dianhydride or a derivative thereof that provides X is preferably a tetracarboxylic acid dianhydride or a derivative thereof having at least one partial structure selected from the group consisting of a benzene ring, a cyclobutane ring, a cyclopentane ring, and a cyclohexane ring. Here, the acyclic aliphatic tetracarboxylic acid dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups bonded to a chain hydrocarbon structure. However, it does not have to be composed solely of a chain hydrocarbon structure, and it may have an alicyclic structure or an aromatic ring structure as part of it. An alicyclic tetracarboxylic acid dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups, including at least one carboxy group bonded to the alicyclic structure. However, none of these four carboxy groups are bonded to an aromatic ring. Furthermore, it does not have to be composed solely of an alicyclic structure, and it may have a chain hydrocarbon structure or an aromatic ring structure as part of it. An aromatic tetracarboxylic acid dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups, including at least one carboxy group bonded to an aromatic ring. However, it does not have to be composed solely of an aromatic ring structure, and it may have a chain hydrocarbon structure or an alicyclic structure as part of it.

[0012] In order to preferably obtain the effects of the present invention, X in the above formula (P0) is selected from the group consisting of the following formulae (Xa1-1) to (Xa1-8), the following formulae (X-1) to (X-17), and the following formula (X ｂ１ -a) to (X ｂ１Further, tetravalent organic groups represented by any one of the following formulae (Xa1-1) to (Xa1-8), (X-1) to (X-17), or (X ｂ１ -a) to (X ｂ１ The tetravalent organic group represented by any one of the above-mentioned groups-c) is a preferred embodiment from the viewpoint of obtaining a liquid crystal alignment film that can suppress afterimages immediately after switching, as will be described later, and can suppress flicker at a high level. (In formulas (Xa1-1) to (Xa1-3), R １ From R １５ each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, or a phenyl group, and may be the same or different. * represents a bond.) (x and y each independently represent a single bond, an ether, a carbonyl, an ester, an alkanediyl group having 1 to 10 carbon atoms, 1,4-phenylene, a sulfonyl, or an amide bond; j and k each represent 0 or 1.)

[0013] R in the above formulas (Xa1-1) to (Xa1-3) １ ~R １５ Specific examples of the alkyl group having 1 to 6 carbon atoms in the above R include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, and an n-pentyl group. １ ~R １５ Specific examples of the alkenyl group having 2 to 6 carbon atoms in the above R include a vinyl group, a propenyl group, and a butenyl group, which may be linear or branched. １ ~R １５ Specific examples of the alkynyl group having 2 to 6 carbon atoms in the above R include an ethynyl group, a 1-propynyl group, a 2-propynyl group, a 1-butynyl group, a 2-butynyl group, and a 3-butynyl group. １ ~R １５In the formula (I), examples of the monovalent organic group having 1 to 6 carbon atoms and containing a fluorine atom include a fluoromethyl group, a trifluoromethyl group, a pentafluoroethyl group, and a pentafluoropropyl group. ａ１ is preferably a tetravalent organic group represented by the above formula (Xa1-1). １ ~R ４ are each independently a hydrogen atom or a methyl group, and R １ ~R ４ Preferably, at least one of R is a methyl group. １ ~R ４ It is more preferable that at least two of R are methyl groups. １ and R ４ is a methyl group, and R ２ and R ３ is a hydrogen atom. The above formula (Xa1-1) is preferably a tetravalent organic group selected from the group consisting of the following formulae (Xa1-1-1) to (Xa1-1-5):

[0014] The above formula (X ｂ１ -a) to (X ｂ１ The tetravalent organic group represented by the following formula (X-c) is, from the viewpoint of suitably obtaining the effects of the present invention, ｂ１ -1) to (X ｂ１ -21) is more preferred.

[0015] Liquid crystal alignment films used in liquid crystal display elements, such as those in the IPS and FFS modes, may require high alignment control to suppress image retention (hereinafter also referred to as AC image retention) caused by long-term AC driving. The use of a liquid crystal alignment agent containing a specific polymer component has been reported as a method for suppressing AC image retention (see, for example, WO 2015 / 060358 ). Furthermore, liquid crystal display elements, such as those in the IPS and FFS modes, are prone to static electricity accumulation within the liquid crystal display element, and charge accumulation can also occur due to the application of asymmetric voltages generated by voltage driving. These accumulated charges can disrupt the alignment of liquid crystal molecules or affect the display as image retention or burn-in, significantly reducing the display quality of the liquid crystal display element. If power is applied again in this state, the liquid crystal molecules will not be properly controlled in the initial stage, resulting in flickering and other issues. In particular, in the IPS and FFS modes, the pixel electrode and the common electrode are closer than in the vertical field mode, resulting in a strong electric field acting on the liquid crystal alignment film and the liquid crystal layer, which can exacerbate these problems. A method for suppressing flicker has been reported, using a liquid crystal alignment agent containing a specific polymer component (see, for example, WO 2015 / 050135 ). With the recent trend toward higher resolution liquid crystal display elements, there is a demand for reducing afterimages (hereinafter also referred to as afterimages immediately after switching) that occur when the display brightness of a liquid crystal display element is significantly changed and then the display brightness is not restored to the original brightness. Furthermore, while flicker suppression is required at a higher level than ever before, conventional liquid crystal alignment agents have not necessarily been able to satisfy all of these characteristics. Therefore, there is a demand for a liquid crystal alignment agent capable of producing a liquid crystal alignment film that can suppress the afterimages immediately after switching that occur when the display brightness is significantly changed and can suppress flicker at a high level, as well as a liquid crystal alignment film and liquid crystal display element obtained from the liquid crystal alignment agent.

[0016] The divalent organic group for Y in the above formula (P0) is not particularly limited, and examples thereof include divalent organic groups represented by the following formulas (3) to (4): The divalent organic groups represented by the following formulas (3) to (4) are preferred embodiments from the viewpoint of obtaining a liquid crystal alignment film that can suppress afterimages immediately after switching and can suppress flicker to a high level. (In formulas (3) and (4), R ３ , R ４ , and R ４’ A each independently represents a halogen atom, a hydroxy group, an optionally protected amino group, a thiol group, a nitro group, a phosphate group, or a monovalent organic group having 1 to 20 carbon atoms. ４ represents an ester bond, an amide bond, a thioester bond, or a divalent organic group having 2 to 20 carbon atoms, provided that 1,4-phenylene group, 1 to 4 of the hydrogen atoms on the phenylene group are R ４ , and R ４’ a3, a4, and a4' are each independently an integer of 0 to 4. a is an integer of 1 to 4. b and c are each independently an integer of 1 to 2. R ３ , R ４ , R ４’ If there are multiple ３ , R ４ , and R ４’ The structures of may be the same or different. When a plurality of a3, a4, and a4' are present, they may be the same or different. * represents a bond.

[0017] R in the above formulas (3) and (4) ３ , R ４ , and R ４’ In the above formula, the monovalent organic group having 1 to 20 carbon atoms includes a monovalent hydrocarbon group having 1 to 20 carbon atoms, and any methylene group of the hydrocarbon group can be replaced with -O-, -S-, -C(=O)-, -C(=O)-O-, -C(=O)-S-, -NR ３ - (However, R ３ represents a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, or a tert-butoxycarbonyl group; ３ - (However, R ３represents a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, or a tert-butoxycarbonyl group.), —Si(R ３ ) ２ - (However, R ３ represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms; —S(═O) ２ - or the like (hereinafter, these groups are also referred to as heteroatom-containing groups (A)), a monovalent group (A2) in which at least one hydrogen atom bonded to a carbon atom of a monovalent hydrocarbon group or a monovalent group A is substituted with a halogen atom, a hydroxy group, an alkoxy group, a nitro group, an amino group which may be protected by a protecting group, a mercapto group, a nitroso group, an alkylsilyl group, an alkoxysilyl group, a silanol group, a sulfino group, a phosphino group, a carboxy group, a cyano group, a sulfo group, an acyl group, or the like, and a monovalent group having a heterocycle. The number of carbon atoms in the group (A), the group (A2), and the monovalent group having a heterocycle is 1 to 20. ３ , R ４ , and R ４’ As the monovalent organic group having 1 to 20 carbon atoms in the above, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, and a monovalent group obtained by replacing any methylene group of the hydrocarbon group with the heteroatom-containing group (A) are more preferred. ２ and R represents a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, or a tert-butoxycarbonyl group. ３ , R ４ , and R ４’ The monovalent organic group having 1 to 20 carbon atoms in the formula (I) is preferably a methyl group, a methoxy group, a vinyl group, a halogen atom, a hydroxy group, an amino group which may be protected by a protecting group, or a monovalent group in which at least one hydrogen atom of an alkyl group having 1 to 3 carbon atoms has been substituted with a halogen atom or an amino group which may be protected by a protecting group.

[0018] In the above formula (3), a is preferably an integer of 1 to 2. In the above formula (3), a3 is preferably an integer of 0 to 2, and when there are multiple a3s, they may be the same or different. In the above formula (4), a4 and a4' are each independently preferably an integer of 0 to 2, and when there are multiple a4s and multiple a4's, they may be the same or different.

[0019] A in the above formula (4) ４ The divalent organic group having 2 to 20 carbon atoms in the formula (I) includes a hydrocarbon group having 2 to 20 carbon atoms; any alkylene group contained in the hydrocarbon group can be selected from the group consisting of -C(=O)-, -NR-, -C(=O)-O-, -Si(R ０ ) ２ and -O-C(=O)- (4a) (wherein the carbon number of the divalent organic group (4a) is 2 to 20); a divalent organic group (4b) in which -O- is inserted at least one position between the terminal of a hydrocarbon group having 2 to 20 carbon atoms and between the carbon-carbon bonds of any alkylene groups contained in the hydrocarbon group; a divalent organic group (4c) in which -O- is inserted at least one position between the carbon-carbon bonds of any alkylene groups contained in the divalent organic group (4a); a divalent organic group (4d) having 2 to 20 carbon atoms and having a heterocyclic ring; and the like. In the above -NR-, R represents a hydrogen atom, a monovalent hydrocarbon group having 1 to 5 carbon atoms, or a tert-butoxycarbonyl group. The above -Si(R ０ ) ２ R in - ０ represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms.

[0020] Examples of the hydrocarbon group include a chain hydrocarbon group, an alicyclic hydrocarbon group, or a hydrocarbon group having an aromatic group (examples of the aromatic ring structure in the aromatic group include a benzene ring, a naphthalene ring, a biphenyl structure, an anthracene ring, etc.). Specific examples of the chain hydrocarbon group include a divalent, straight-chain or branched hydrocarbon group having 1 to 20 carbon atoms without a cyclic structure, and are preferably an alkylene group having 1 to 20 carbon atoms, an alkenylene group having 2 to 20 carbon atoms, or an alkynylene group having 2 to 20 carbon atoms. Specific examples of the alicyclic hydrocarbon group include an alicyclic structure (e.g., a cyclohexylene group or a bicyclohexylene group), or a hydrocarbon group having an alicyclic structure and a chain hydrocarbon structure. Specific examples of the hydrocarbon group having an aromatic group include an aromatic group, a hydrocarbon group having an aromatic group and a chain hydrocarbon structure, a hydrocarbon group having an aromatic group and an alicyclic structure, etc.

[0021] Examples of the heterocyclic ring in the divalent organic group (4d) include a piperidine ring, a piperazine ring, a morpholine ring, a pyrrolidine ring, a pyrrole ring, a furan ring, a thiophene ring, an imidazole ring, a pyrazole ring, an imide ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, a pyridine ring, a pyrimidine ring, a pyridazine ring, or a pyrazine ring, or a fused ring containing such a ring structure as a part of its structure, and the hydrogen atoms on the ring may be substituted. Examples of the substituent include a halogen atom, a methyl group, or a methoxy group.

[0022] A in the above formula (4) ４ From the viewpoint of suitably obtaining the effects of the present invention, １ -A-L １’ -" or a divalent organic group having 2 to 20 carbon atoms and a heterocyclic ring is preferred. １ -A-L １’ L in "-" １ , L １’ The total number of carbon atoms in L and A is 2 to 20. １ and L １’each independently represents a single bond, —O—, —NR—, —C(═O)—NR—, —C(═O)—, or —O—C(═O)—, and R represents a hydrogen atom, a monovalent hydrocarbon group having 1 to 5 carbon atoms, or a tert-butoxycarbonyl group. １ -A-L １’ In order to obtain the effects of the present invention, A in "-" is an alkylene group having 1 to 12 carbon atoms, -CH=CH-, -C≡C-, -CR ０ =CR ０’ -C(=O)-O-(R ０ and R ０’ each independently represents a hydrogen atom or a methyl group, or —O—, —NR—, —C(═O)—NR—, —C(═O)—NR—C(═O)—, —C(═O)—O—, —Si(R ａ ) ２ represents a divalent organic group into which at least one group of - and -O-C(=O)- is inserted, such as -O-Ar-O-, -O-C(=O)-Ar-C(=O)-O-, or -C(=O)-O-Ar-O-C(=O)-. １ and L １’ represents a single bond, A represents a group other than a methylene group. R in the above -C(=O)-NR- and -C(=O)-NR-C(=O)- represents a hydrogen atom, a monovalent hydrocarbon group having 1 to 5 carbon atoms, or a tert-butoxycarbonyl group. -Si(R ａ ) ２ R in - ａ represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 3 carbon atoms. Any hydrogen atom possessed by A may be substituted with a halogen atom. Ar in the above -O-Ar-O-, -O-C(=O)-Ar-C(=O)-O-, and -C(=O)-O-Ar-O-C(=O)- represents a phenylene group or a biphenyl structure.

[0023] More preferred examples of the above formulas (3) and (4) include the following formula (d ＡＬ -1) to (d ＡＬExamples of the structures represented by the following formula (d ＡＬ -1) to (d ＡＬ In the structures represented by the following formula (d ＡＬ In formula (9), all of the benzene rings are bonded at the 1,4-positions. (Formula (d ＡＬ In formula (d-6), when m1 and m2 are 0, the sum of m1, m2 and n is 1 to 12, and when at least one of m1 and m2 is an integer other than 0, the sum of m1, m2 and n is 2 to 12. ＡＬ In formula (d-8), the sum of m1, m2 and n is 3 to 12. ＡＬ -11) and formula (d ＡＬ -12), the sum of m1, m2 and n is 3 to 12.

[0024] From the viewpoint of suitably achieving the effects of the present invention, the polymer (P) is preferably a polymer containing a structural unit having a divalent organic group selected from the group consisting of a divalent organic group having a urea bond; a divalent organic group having an amide bond; a divalent organic group having at least one nitrogen atom-containing structure selected from the group consisting of a nitrogen atom-containing heterocycle, a secondary amino group, and a tertiary amino group; and a divalent organic group having a carboxy group (these are also collectively referred to as the specific divalent organic group (b)).

[0025] Examples of the divalent organic group having a urea bond include A in the above formula (4). ４ The divalent organic group having an amide bond is represented by the formula (4) above, in which A has the group "-NH-C(=O)-NR-". ４Examples of the divalent organic group having at least one nitrogen atom-containing structure selected from the group consisting of a nitrogen atom-containing heterocycle, a secondary amino group, and a tertiary amino group include 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, 3,6-diaminoacridine, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, and the divalent organic group having a structure represented by any one of the above formulas (z-1) to (z-7). and divalent organic groups obtained by removing two amino groups from a diamine selected from the group consisting of heterocycle-containing diamines such as diamines; and diamines having a diphenylamine structure typified by 4,4'-diaminodiphenylamine, 4,4'-diaminodiphenyl-N-methylamine, N,N'-bis(4-aminophenyl)-benzidine, N,N'-bis(4-aminophenyl)-N,N'-dimethylbenzidine, or N,N'-bis(4-aminophenyl)-N,N'-dimethyl-1,4-benzenediamine. Examples of the divalent organic group having a carboxy group include divalent organic groups obtained by removing two amino groups from a diamine having a carboxy group, such as 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 3,5-diaminobenzoic acid, 4,4'-diaminobiphenyl-3-carboxylic acid, 4,4'-diaminodiphenylmethane-3-carboxylic acid, 1,2-bis(4-aminophenyl)ethane-3-carboxylic acid, 4,4'-diaminobiphenyl-3,3'-dicarboxylic acid, 4,4'-diaminobiphenyl-2,2'-dicarboxylic acid, 3,3'-diaminobiphenyl-4,4'-dicarboxylic acid, 3,3'-diaminobiphenyl-2,4'-dicarboxylic acid, 4,4'-diaminodiphenylmethane-3,3'-dicarboxylic acid, 1,2-bis(4-aminophenyl)ethane-3,3'-dicarboxylic acid, and 4,4'-diaminodiphenylether-3,3'-dicarboxylic acid.

[0026] In addition, Y in the above formula (A1) ａ１The divalent organic group may have a structure other than the divalent organic groups represented by the formulas (3) and (4). Examples of such a structure include a divalent organic group (3L) in which the bonding position of the benzene ring bonded to * in the formula (3) is changed from the 1,4-position to the 2,5-position; a divalent organic group (4L) in which at least one bonding position of the benzene ring bonded to * in the formula (4) is changed from the 1,4-position to the 2,5-position; or a divalent organic group obtained by removing two amino groups from the following diamine (the diamines are also collectively referred to as diamine (W)). In the divalent organic groups (3L) and (4L), R ３ , R ４ , R ４’ , A ４ , a3, a4, a4', a, b, and c have the same meanings as those in the formulas (3) and (4).

[0027] Aromatic diamines having a naphthalene ring such as 1,2-bis(6-amino-2-naphthyloxy)ethane, 1,2-bis(6-amino-2-naphthyl)ethane, or 6-[2-(4-aminophenoxy)ethoxy]-2-naphthylamine, 4,4'-diaminoazobenzene, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diamino diphenyl ether; diamines having a photopolymerizable group at the terminal such as 2-(2,4-diaminophenoxy)ethyl methacrylate and 2,4-diamino-N,N-diallylaniline; benzoin or its alkyl ethers, benzil ketals, acetophenone, benzoin exemplified by 1-(4-(2-(2,4-diaminophenoxy)ethoxy)phenyl)-2-hydroxy-2-methylpropanone and 2-(4-(2-hydroxy-2-methylpropanoyl)phenoxy)ethyl-3,5-diaminobenzoate; diamines having a group that exhibits a radical polymerization initiator function in the molecule, such as acetophenones (preferably an α-hydroxyacetophenone structure or an α-aminoacetophenone structure), acylphosphine oxides, and benzophenones (preferably a benzophenone structure or an aminobenzophenone structure); 4,4'-diaminobenzophenone, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, 3, 6-diaminoacridine, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, 4,4'-diaminodiphenylamine, 4,4'-diaminodiphenyl-N-methylamine, 4-(2-(methylamino)ethyl)aniline, 4-(2-aminoethyl)aniline, 1-(4-aminophenyl)-1,3,3-trimethyl-1H-indan-5-amine, 1-(4-aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H-inden-6-amine;Diamines having a steroid skeleton such as cholestanyloxy-3,5-diaminobenzene, cholestenyloxy-3,5-diaminobenzene, cholestanyloxy-2,4-diaminobenzene, cholestanyl 3,5-diaminobenzoate, cholestanyl 3,5-diaminobenzoate, lanostannyl 3,5-diaminobenzoate, and 3,6-bis(4-aminobenzoyloxy)cholestane; diamines represented by the following formulae (V-1) and (V-2) (wherein -NH; ２ The bonding position of the benzene ring to which -NH is bonded is other than the 1,4-position. ２ The bonding positions of the benzene ring bonded to are preferably the 1,3-positions.); diamines having a siloxane bond such as 1,3-bis(3-aminopropyl)-tetramethyldisiloxane; metaxylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, 1,3-bis(aminomethyl)cyclohexane, 1,4-diaminocyclohexane, 4,4'-methylenebis(cyclohexylamine), diamines in which two amino groups are bonded to a group represented by any one of formulas (Y-1) to (Y-167) described in WO2018 / 117239, and the like. In the above formula (V-1), m and n are integers of 0 to 3, and satisfy the relationship 1≦m+n≦4. １ is -(CH ２ ) ａ -(a is an integer of 1 to 15), -CONH-, -NHCO-, -CO-N(CH ３ )-, -NH-, -O-, -CH ２ O-, -CH ２ represents —OCO—, —COO—, or —OCO—. １ represents a monovalent group such as a fluorine atom, a fluorine atom-containing alkyl group having 1 to 10 carbon atoms, a fluorine atom-containing alkoxy group having 1 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an alkoxyalkyl group having 2 to 10 carbon atoms. ２ is -O-, -CH ２ O-, -CH ２ represents —OCO—, —COO—, or —OCO—;

[0028] From the viewpoint of suitably achieving the effects of the present invention, the polymer (P) preferably contains the structural unit (p0) and the imidized structural units of the structural unit (p0) in a total amount of 10 to 100 mol %, more preferably 15 to 100 mol %, of all structural units contained in the polymer (P). Note that this total also includes cases where either the structural unit (p0) or the imidized structural units of the structural unit (p0) is 0 mol %. Hereinafter, the term "total" also includes cases where one or more of the structural unit components are 0 mol %.

[0029] From the viewpoint of suitably obtaining the effects of the present invention, the polymer (P) preferably contains structural units having a divalent organic group represented by the above formulas (3) and (4) in an amount of 10 to 100 mol %, more preferably 15 to 100 mol %, of all structural units contained in the polymer (P).

[0030] The monovalent organic groups for R and Z in the formula (P0) include monovalent hydrocarbon groups having 1 to 20 carbon atoms, and methylene groups of the hydrocarbon groups may be substituted with -O-, -S-, -CO-, -COO-, -COS-, -NR ３ --CO-NR ３ -, -Si(R ３ ) ２ -, -SO ２ - or the like (wherein R ３ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms, and R ３ If there are multiple R ３may be the same or different. ) Examples include monovalent groups in which at least one hydrogen atom bonded to a carbon atom of such a monovalent hydrocarbon group or monovalent group A is substituted with a halogen atom, a hydroxy group, an alkoxy group, a nitro group, an amino group, a mercapto group, a nitroso group, an alkylsilyl group, an alkoxysilyl group, a silanol group, a sulfino group, a phosphino group, a carboxy group, a cyano group, a sulfo group, an acyl group, or the like, and monovalent groups having a heterocycle. The monovalent organic groups represented by R and Z in the above formula (1) are preferably alkyl groups having 1 to 10 carbon atoms, alkenyl groups having 2 to 10 carbon atoms, alkynyl groups having 2 to 10 carbon atoms, Boc, or Fmoc, more preferably alkyl groups having 1 to 3 carbon atoms, and even more preferably methyl groups. From the viewpoint of suitably achieving the effects of the present invention, R and Z are each independently preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably a hydrogen atom or a methyl group.

[0031] The polymer component (P) contained in the liquid crystal aligning agent of the present invention may be a polymer component containing two or more polymers and satisfying at least one of the following conditions (i) to (iii): (i) polymer component (P1) containing two or more polymers selected from the group consisting of polyimide precursors (A) having one or more structural units and having a structural unit (a1) represented by the following formula (A1) and polyimides which are imidized products of the polyimide precursors; (ii) polymer component (P2) containing two or more polyimide precursors (B) which are different from the polyimide precursor (A), have one or more structural units and have a structural unit (b1) represented by the following formula (B1); and (iii) polymer component (P3) containing the polyimide precursor (B) and at least one polymer selected from the group consisting of the polyimide precursors (A) and polyimides which are imidized products of the polyimide precursors. (In formula (A1), X ａ１ represents a tetravalent organic group selected from the group consisting of the above formulae (Xa1-1) to (Xa1-8), Y ａ１ represents a divalent organic group. In the above formula (A1), R and Z have the same meanings as in the above formula (P0). (In formula (B1), Xｂ１ represents a tetravalent organic group having an aromatic group having 6 to 30 carbon atoms; X ｂ１ At least one of the carbonyl carbons bonded to X ｂ１ It bonds to the aromatic group of Y. ｂ１ represents a divalent organic group. In the above formula (B1), R and Z have the same meanings as in the above formula (P0).

[0032] The polymer component (P) may be composed of a polymer that does not have an acid-dissociable group. Here, the acid-dissociable group is a group having a bond that is cleaved by acid, and upon cleavage of the bond, some or all of the acid-dissociable group is dissociated from the main chain of the polymer. Preferred examples of the acid-dissociable group include protecting groups that protect amino groups, hydroxy groups, and the like. Examples of such protecting groups include carbamate-based protecting groups (specific examples include tert-butoxycarbonyl and 9-fluorenylmethyloxycarbonyl), and groups that form an acetal structure or a tertiary ether structure together with the protected oxygen atom. A polymer that does not have an acid-dissociable group can be obtained, for example, by using a raw material component that does not have an acid-dissociable group (specific examples of raw materials that do not have an acid-dissociable group include a diamine that does not have an acid-dissociable group, a tetracarboxylic dianhydride or a derivative thereof that does not have an acid-dissociable group, and a terminal modifier that does not form an acid-dissociable group).

[0033] <Polyimide precursor (A)> The polymer components (P1) and (P3) contained in the liquid crystal aligning agent of the present invention contain a polyimide precursor (A) having one or more structural units and having a structural unit (a1) represented by the above formula (A1). The polyimide precursor (A) may be one or more polymers. The polyimide precursor (A) may have one type of structural unit, two or more different structural units, three or more different structural units, or four or more different structural units.

[0034] Y in the above formula (A1) ａ１The divalent organic group is not particularly limited, and examples thereof include divalent organic groups represented by the above formulas (3) to (4). The divalent organic group is introduced into the structural units of the polyimide precursor (A), for example, by using a diamine having the above divalent organic group as the diamine component for obtaining the polyimide precursor (A). From the viewpoint of suitably achieving the effects of the present invention, at least one of the structural units constituting the polyimide precursor (A) preferably has a structure selected from the group consisting of divalent organic groups represented by the above formulas (3) to (4), and more preferably has a structure selected from the group consisting of divalent organic groups represented by the above formulas (3) to (4) in which * is bonded to a nitrogen atom derived from the diamine. Furthermore, from the viewpoint of suitably achieving the effects of the present invention, in the above formula (A1), Y ａ１ is preferably a divalent organic group selected from the group consisting of the above formulas (3) and (4).

[0035] More preferred examples of the formulas (3) and (4) are the same as the preferred embodiments of the formulas (3) to (4) in the polymer (P). Among them, more preferred examples include the formula (d ＡＬ -1) to (d ＡＬ Examples of the structures represented by the formula (d ＡＬ -1) to (d ＡＬ In the structures represented by the following formula (d ＡＬ In formula (9), all of the benzene rings are bonded at the 1,4-positions.

[0036] In addition, Y in the above formula (A1) ａ１The divalent organic group may have a structure other than the divalent organic groups represented by the formulas (3) and (4). Examples of such a structure include a divalent organic group (3L) in which the bonding position of the benzene ring bonded to * in the formula (3) is changed from the 1,4-position to the 2,5-position; a divalent organic group (4L) in which at least one bonding position of the benzene ring bonded to * in the formula (4) is changed from the 1,4-position to the 2,5-position; or a divalent organic group obtained by removing two amino groups from the diamine (W). In the divalent organic groups (3L) and (4L), R ３ , R ４ , R ４’ , A ４ , a3, a4, a4', a, b, and c have the same meanings as those in the formulas (3) and (4).

[0037] From the viewpoint of suitably achieving the effects of the present invention, the polyimide precursor (A) may be a polyimide precursor having, in addition to the structural unit (a1) represented by the above formula (A1), a structural unit (a2) represented by the following formula (A2): (In formula (A2), X ａ２ represents a tetravalent organic group represented by any one of the above formulas (X-1) to (X-17) or a tetravalent organic group derived from an aromatic tetracarboxylic dianhydride, Y ａ２ represents a divalent organic group. In the above formula (A2), R and Z have the same meanings as in the above formula (P0).

[0038] Y in the above formula (A2) ａ２ Specific examples of the divalent organic group include Y in the above formula (A1). ａ１ Examples of the divalent organic group include the structures exemplified above, including preferred embodiments.

[0039] The aromatic tetracarboxylic dianhydride is as defined above, including preferred embodiments. Specific preferred examples of the aromatic tetracarboxylic dianhydride include those represented by the above formula (X ｂ１ -a) to (X ｂ１ -c), and more preferably, ｂ１ -1) to (X ｂ１ -21).

[0040] From the viewpoint of suitably achieving the effects of the present invention, the polyimide precursor (A) preferably contains 10 to 100 mol %, more preferably 15 to 100 mol %, of the total structural units contained in the polyimide precursor (A) of the structural unit (a1) and the imidized structural units of the structural unit (p0). From the viewpoint of suitably achieving the effects of the present invention, the polyimide precursor (A) preferably contains 10 to 100 mol %, more preferably 15 to 100 mol %, of the total structural units contained in the polyimide precursor (A) of the structural units having divalent organic groups represented by the above formulas (3) and (4). When the polyimide precursor (A) contains structural units other than the structural unit (a1) and / or the imidized structural units of the repeating unit (a1), the total of the structural unit (a1) and the imidized structural units of the structural unit (a1) preferably constitutes 95 mol % or less, more preferably 90 mol % or less, of the total structural units contained in the polyimide precursor (A).

[0041] <Polyimide precursor (B)> The polymer components (P2) and (P3) contained in the liquid crystal aligning agent of the present invention contain a polyimide precursor (B), which is a polymer different from the polyimide precursor (A) and has one or more structural units, including a structural unit (b1) represented by the following formula (B1). One or more types of polymers may be used as the polyimide precursor (B). The polyimide precursor (B) may have one type of structural unit, or two or more different types of structural units, or three or more different types of structural units, or four or more different types of structural units. (In formula (B1), X ｂ１ represents a tetravalent organic group having an aromatic group having 6 to 30 carbon atoms; X ｂ１ At least one of the carbonyl carbons bonded to X ｂ１ It bonds to the aromatic group of Y. ｂ１ represents a divalent organic group. In the above formula (B1), R and Z have the same meanings as in the above formula (P0).

[0042] X in the above formula (B1) ｂ１ represents a tetravalent organic group having an aromatic group having 6 to 30 carbon atoms; X ｂ１At least one of the carbonyl carbons bonded to X ｂ１ More preferably, it is a tetravalent organic group derived from an acid dianhydride obtained by intramolecular dehydration of four carboxy groups, including at least one carboxy group bonded to an aromatic ring (such as a benzene ring or a naphthalene ring). However, it is not necessary for the group to be composed of only an aromatic ring structure, and it may also have a chain hydrocarbon structure or an alicyclic structure as part of it. X ｂ１ A preferred example of X is a tetravalent organic group derived from an aromatic tetracarboxylic acid compound. ｂ１ is preferably represented by the above formula (X ｂ１ -a) to (X ｂ１ -c), and more preferably, a tetravalent organic group represented by the above formula (X ｂ１ -1) to (X ｂ１ -21), and more preferably, a tetravalent organic group represented by the above formula (X ｂ１ -1) to (X ｂ１ A tetravalent organic group represented by any one of the formulas (X-13) is more preferred. ｂ１ -1) to (X ｂ１ -7).

[0043] Above Y ｂ１ The divalent organic group in ａ１ In order to obtain the effects of the present invention, the polyimide precursor (B) is preferably a polymer containing a structural unit having the specific divalent organic group (b). In addition, in order to obtain the effects of the present invention, the polyimide precursor (B) is preferably a polymer containing a structural unit having the specific divalent organic group (b) described above. ｂ１ is preferably a polymer containing a structural unit which is the specific divalent organic group (b) described above.

[0044] From the viewpoint of suitably obtaining the effects of the present invention, the polyimide precursor (B) preferably contains structural units having the specific divalent organic group (b) (more preferably structural units having the specific divalent organic group bonded to a nitrogen atom derived from a diamine) in an amount of 1 mol % or more, preferably 5 mol % or more, more preferably 10 mol % or more, and even more preferably 20 mol % or more of the total structural units contained in the polyimide precursor (B). ｂ１ is the specific divalent organic group (b) in an amount of 1 mol % or more, preferably 5 mol % or more, more preferably 10 mol % or more, and even more preferably 20 mol % or more of all structural units contained in the polyimide precursor (B).

[0045] From the viewpoint of suitably achieving the effects of the present invention, the polyimide precursor (B) may be a polyimide precursor having, in addition to the structural unit (b1) represented by the above formula (B1), a structural unit (b2) represented by the following formula (B2): (In formula (B2), X ｂ２ represents a tetravalent organic group derived from an acyclic aliphatic tetracarboxylic acid dianhydride or an alicyclic tetracarboxylic acid dianhydride; Y ｂ２ represents a divalent organic group. In the above formula (B2), R and Z have the same meanings as in the above formula (P0).

[0046] In the formula (B2), the acyclic aliphatic tetracarboxylic acid dianhydride and the alicyclic tetracarboxylic acid dianhydride are as defined above.

[0047] X ｂ２ is preferably a tetravalent organic group represented by any one of the above formulas (X-1) to (X-17) or (Xa1-1) to (Xa1-8), from the viewpoint of suitably obtaining the effects of the present invention.

[0048] From the viewpoint of optimally achieving the effects of the present invention, the polyimide precursor (B) preferably contains the structural unit (b1) and the imidized structural unit of the structural unit (p0) in a total amount of 10 to 100 mol%, more preferably 15 to 100 mol%, of the total structural units contained in the polyimide precursor (B). Furthermore, when the polyimide precursor (B) contains structural units other than the structural unit (b1) and / or the imidized structural unit of the repeating unit (b1), the structural unit (b1) preferably accounts for 95 mol% or less, more preferably 90 mol% or less, of the total structural units contained in the polyimide precursor (B). The polyimide precursor (B) preferably contains the structural unit (b2) in an amount of 5 mol% or more, more preferably 10 mol% or more, of the total structural units contained in the polyimide precursor (B). Furthermore, the structural unit (b2) preferably accounts for 90 mol% or less, more preferably 85 mol% or less, of the total structural units contained in the polyimide precursor (B).

[0049] In the polymer component (P), the mass ratio of the content of the first polyimide precursor to the content of the second polyimide precursor (content of the first polyimide precursor / content of the second polyimide precursor) is preferably 10 / 90 to 90 / 10, more preferably 20 / 80 to 90 / 10, and even more preferably 20 / 80 to 80 / 20. From the viewpoint of reducing afterimages resulting from residual DC, the mass ratio of the content of the polyimide precursor (A) to the content of the polyimide precursor (B) (content of the polyimide precursor (A) / content of the polyimide precursor (B)) is preferably 10 / 90 to 90 / 10, more preferably 20 / 80 to 90 / 10, and even more preferably 20 / 80 to 80 / 20.

[0050] <Method for Producing Polymer (P), Polyimide Precursor (A), and Polyimide Precursor (B)> The polymer (P) and polyimide precursors (A) and (B) of the present invention can be synthesized by a known method such as that described in WO2013 / 157586.

[0051] Specifically, it can be obtained by reacting a tetracarboxylic acid derivative component containing a tetracarboxylic acid dianhydride with a diamine component in a solvent (condensation polymerization). The solvent is not particularly limited as long as it dissolves the produced polymer.

[0052] For example, when synthesizing a polyimide precursor (A) having a repeating unit represented by the above formula (A1), the diamine component may be -NZ-Y ａ１ -NZ- structure (Y ａ１ , Z is Y in formula (A1) ａ１ The tetracarboxylic acid derivative component is a diamine having the above formula (X ａ１ ) structure (X ａ１ is X in formula (A1) ａ１ The tetracarboxylic dianhydride having the same definition as that of the tetracarboxylic dianhydride having the same meaning ...

[0053] The ratio of tetracarboxylic dianhydride and diamine used in the polyimide precursor synthesis reaction is preferably such that 0.5 to 2 equivalents of the acid anhydride groups of the tetracarboxylic dianhydride are used per equivalent of the amino groups of the diamine, more preferably 0.8 to 1.2 equivalents. As with conventional polycondensation reactions, the closer the equivalent of the acid anhydride groups of the tetracarboxylic dianhydride is to 1 equivalent, the higher the molecular weight of the resulting polyimide precursor. The reaction temperature in the polyimide precursor synthesis reaction is preferably −20 to 150°C, more preferably 0 to 100°C. The reaction time is preferably 0.1 to 24 hours, more preferably 0.5 to 12 hours. The polyimide precursor synthesis reaction can be carried out at any concentration, but the concentration of the polyimide precursor in the reaction solution is preferably 1 to 50% by mass, more preferably 5 to 30% by mass. The reaction can be carried out at a high concentration initially, with subsequent addition of solvent.

[0054] Specific examples of the solvent used when reacting the diamine component with the tetracarboxylic acid derivative component include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, and 1,3-dimethyl-2-imidazolidinone. When the polymer has high solvent solubility, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, or H ３ C-CH(OH)-CH ２ -O-D１ (D １ represents an alkyl group having 1 to 3 carbon atoms, HO—CH ２ -CH ２ -O-D ２ (D ２ represents an alkyl group having 1 to 3 carbon atoms, HO—CH ２ -CH ２ -O-CH ２ -CH ２ -D ３ (D ３ represents an alkyl group having 1 to 4 carbon atoms.) These solvents may be used alone or in combination.

[0055] The above H ３ C-CH(OH)-CH ２ -O-D １ , HO-CH ２ -CH ２ -O-D ２ , HO-CH ２ -CH ２ -O-CH ２ -CH ２ -D ３ Specific examples of the solvent represented by the formula (I) include propylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, diethylene glycol monomethyl ether, and diethylene glycol monoethyl ether.

[0056] <Solution Viscosity and Molecular Weight of Polymer> In the present invention, the polymer (P), polyimide precursor (A), and polyimide precursor (B) preferably have a solution viscosity of, for example, 10 to 1,000 mPa s when made into a solution of 10 to 15 mass % from the viewpoint of workability, but are not particularly limited thereto. The solution viscosity (mPa s) of the polymer is a value measured at 25°C using an E-type rotational viscometer for a polymer solution of 10 to 15 mass % prepared using a good solvent for the polymer (e.g., γ-butyrolactone, N-methyl-2-pyrrolidone, etc.).

[0057] The weight average molecular weight (Mw) of the polymer (P), polyimide precursor (A), and polyimide precursor (B) measured by gel permeation chromatography (GPC) in terms of polystyrene is preferably 1,000 to 500,000, and more preferably 2,000 to 300,000. The molecular weight distribution (Mw / Mn), expressed as the ratio of Mw to the number average molecular weight (Mn) measured by GPC in terms of polystyrene, is preferably 15 or less, and more preferably 10 or less. A molecular weight within this range is preferred from the viewpoint of optimally achieving the effects of the present invention.

[0058] <End-capping agent> When synthesizing the polymer (P), polyimide precursor (A), and polyimide precursor (B) of the present invention, a suitable end-capping agent may be used together with the above-mentioned tetracarboxylic acid derivative component and diamine component to form an end-capping type polymer. The end-capping type polymer has the effect of improving the film hardness of the liquid crystal alignment film obtained by coating and improving the adhesion properties between the sealant and the liquid crystal alignment film.

[0059] Examples of the terminal groups of the polymer (P), polyimide precursor (A), and polyimide precursor (B) in the present invention include an amino group, a carboxy group, an acid anhydride group, or derivatives thereof. The amino group, carboxy group, and acid anhydride group can be obtained by a conventional condensation reaction or by blocking the terminals with the following terminal blocking agents, for example, they can be obtained in the same manner using the following terminal blocking agents.

[0060] Examples of the end-capping agent include acid monoanhydrides such as acetic anhydride, maleic anhydride, nadic anhydride, phthalic anhydride, itaconic anhydride, cyclohexanedicarboxylic anhydride, 3-hydroxyphthalic anhydride, trimellitic anhydride, 3-(3-trimethoxysilyl)propyl)-3,4-dihydrofuran-2,5-dione, 4,5,6,7-tetrafluoroisobenzofuran-1,3-dione, and 4-ethynylphthalic anhydride; dicarbonic acid diester compounds such as di-tert-butyl dicarbonate and diallyl dicarbonate; chlorocarbonyl compounds such as acryloyl chloride, methacryloyl chloride, and nicotinic acid chloride; aniline, 2-aminophenol, 3-aminophenol, 4 ... monoamine compounds such as 5-aminosalicylic acid, 5-aminosalicylic acid, 6-aminosalicylic acid, 2-aminobenzoic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, and n-octylamine; monoisocyanate compounds such as isocyanates having an unsaturated bond, such as ethyl isocyanate, phenyl isocyanate, naphthyl isocyanate, 2-acryloyloxyethyl isocyanate, and 2-methacryloyloxyethyl isocyanate; and isothiocyanate compounds such as ethyl isothiocyanate and allyl isothiocyanate.

[0061] The proportion of the end-capping agent used is preferably 0.01 to 20 parts by mole, more preferably 0.01 to 10 parts by mole, per 100 parts by mole of the total of the diamine components used.

[0062] <Compound (C)> The liquid crystal aligning agent of the present invention contains one or more compounds (component (C)) selected from the group consisting of cyclic monoterpene compounds (compound (C)). Examples of the terpene compound of compound (C) include monoterpenes having 10 carbon atoms and derivatives thereof (including compounds having 10 or more carbon atoms), and specific examples thereof include terpene hydrocarbons, terpene alcohols, and terpene ketones. Here, monoterpenes are compounds having 10 carbon atoms and composed of two isoprene units, and the terpene compounds may be monocyclic or bicyclic. From the viewpoint of suitably achieving the effects of the present invention, compound (C) is preferably a solvent, more preferably a solvent having a boiling point at normal pressure of less than 260°C, even more preferably a solvent having a boiling point of 230°C or less, and most preferably a solvent having a boiling point of 200°C or less. Furthermore, the boiling point at normal pressure is preferably 100°C or higher, and more preferably 150°C or higher. The boiling point of the cyclic monoterpene compound of compound (C) can be cited from literature such as "Perfume and Flavor Chemicals" Vol. I and II, Steffen Arctander, Allured Pub. Co. (1994), "Synthetic Fragrances: Chemistry and Product Knowledge", by Genichi Indo, The Chemical Daily Co. (1996), "Perfume and Flavor Materials of Natural Origin", by Steffen Arctander, Allured Pub. Co. (1994), "Encyclopedia of Fragrances", edited by the Japan Fragrance Association, Asakura Shoten (1989), and "Fundamental Knowledge of Fragrances and Fragrance Blending", Sangyo Tosho (1995). Examples of terpene hydrocarbons include limonene (D-limonene, L-limonene, DL-limonene), pinene (α-pinene, β-pinene), camphene, phellandrene (α-phellandrene, β-phellandrene), terpinene (α-terpinene, β-terpinene, γ-terpinene), terpinolene, and 3-carene.Examples of terpene alcohols or derivatives thereof include isopulegol, menthol (D-menthol, L-menthol, DL-menthol), terpineol (α-terpineol, β-terpineol, γ-terpineol), carveol, dihydrocarveol, perilla alcohol (perillyl alcohol), 4-thuyanol, isocyclogeraniol, α-fenchyl alcohol (fenchol), borneol, isoborneol, etc. Examples of terpene ketones include camphor, etc.

[0063] The content of the (C) component is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and even more preferably 0.3% by mass or more, when all components in the liquid crystal aligning agent are taken as 100% by mass. Furthermore, from the viewpoint of suitably obtaining the effects of the present invention, the content of the (C) component is preferably 20% by mass or less, more preferably 10% by mass or less, more preferably 5% by mass or less, and even more preferably 3% by mass or less, when all components in the liquid crystal aligning agent are taken as 100% by mass. Furthermore, the proportion of the total mass of the components other than the (C) component in the liquid crystal aligning agent to the total mass of the liquid crystal aligning agent is 99.9% by mass or less, more preferably 99.8% by mass or less, and even more preferably 99.7% by mass or less, when all components in the liquid crystal aligning agent are taken as 100% by mass. Furthermore, the proportion of the total mass of the components other than the (C) component in the liquid crystal aligning agent to the total mass of the liquid crystal aligning agent is preferably 80% by mass or more, more preferably 90% by mass or more, when all components in the liquid crystal aligning agent are taken as 100% by mass.

[0064] The liquid crystal aligning agent of the present invention contains an organic solvent (excluding the compound (C)). Specific examples of the organic solvent include N,N-dimethylformamide, N,N-dimethylacetamide, N,N-dimethyllactamide, N,N-dimethylpropionamide, tetramethylurea, N,N-diethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethyl sulfoxide, γ-butyrolactone, γ-valerolactone, 1,3-dimethyl-2-imidazolidinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, 3-methoxy-N ...propionamide, tetramethylurea, N,N-diethylpropionamide, tetramethylurea, N,N-diethylpropionamide, tetramethylurea, N,N-diethylpropionamide, tetramethylurea, N,N-diethylpropionamide, tetramethylurea, N,N-diethylpropionamide, tetramethylurea, N,N-diethylpropionamide, Examples of good solvents include propanamide, 3-butoxy-N,N-dimethylpropanamide, N-(n-propyl)-2-pyrrolidone, N-isopropyl-2-pyrrolidone, N-(n-butyl)-2-pyrrolidone, N-(tert-butyl)-2-pyrrolidone, N-(n-pentyl)-2-pyrrolidone, N-methoxypropyl-2-pyrrolidone, N-ethoxyethyl-2-pyrrolidone, N-methoxybutyl-2-pyrrolidone, and N-cyclohexyl-2-pyrrolidone (collectively referred to as "good solvents"). Among these, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, and γ-butyrolactone are preferred. The content of the good solvent is preferably 20% by mass or more, and more preferably 30% by mass or more, when the total amount of all components in the liquid crystal aligning agent is 100% by mass.

[0065] Furthermore, the organic solvent contained in the liquid crystal aligning agent is preferably a mixed solvent containing, in addition to the above solvent, a solvent (also referred to as a poor solvent) that improves the coatability and surface smoothness of the coating film when the liquid crystal aligning agent is applied. The content of the poor solvent is preferably 1% by mass or more, more preferably 5% by mass or more, and even more preferably 10% by mass or more, when the total mass of all components in the liquid crystal aligning agent is 100% by mass. The total content of the good solvent and the poor solvent is preferably 99.9% by mass or less, more preferably 99.8% by mass or less, and even more preferably 99.7% by mass or less, when the total mass of all components in the liquid crystal aligning agent is 100% by mass. The type and content of the poor solvent are appropriately selected depending on the coating device, coating conditions, coating environment, etc. of the liquid crystal aligning agent. Specific examples of the poor solvent are listed below, but are not limited to these.

[0066] Diisopropyl ether, diisobutyl ether, diisobutyl carbinol (2,6-dimethyl-4-heptanol), ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, 4-hydroxy-4-methyl-2-pentanone, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, 3-ethoxybutyl acetate, 1-methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, ethylene glycol diacetate, propylene carbonate, ethylene carbonate, ethylene glycol monobutyl ether, ethylene glycol monoisoamyl ether, ethylene glycol monohexyl ether, propylene glycol monobutyl ether, 1-(2-butoxyethoxy)-2-propanol, 2-(2-butoxyethoxy)-1-propanol, propylene glycol monomethyl ether ethyl acetate, propylene glycol diacetate, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monobutyl ether acetate, diethylene glycol monopropyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 2-(2-ethoxyethoxy)ethyl acetate, diethylene glycol diacetate, propylene glycol diacetate, n-butyl acetate, propylene glycol monoethyl ether acetate, cyclohexyl acetate, 4-methyl-2-pentyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, butyl 3-methoxypropionate, n-butyl lactate, isoamyl lactate, diethylene glycol monoethyl ether, diisobutyl ketone (2,6-dimethyl-4-heptanone), and the like.

[0067] Of these, the poor solvent is preferably diisobutyl carbinol, propylene glycol monobutyl ether, propylene glycol diacetate, diethylene glycol diethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, or diisobutyl ketone.

[0068] Preferred solvent combinations of a good solvent and a poor solvent include N-methyl-2-pyrrolidone and ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone and ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone and propylene glycol monobutyl ether, N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether, N-ethyl-2-pyrrolidone and 4-hydroxy-4-methyl-2-pentanone, and N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether. diacetate, N,N-dimethyl lactamide and diisobutyl ketone, N-methyl-2-pyrrolidone and ethyl 3-ethoxypropionate, N-ethyl-2-pyrrolidone and ethyl 3-ethoxypropionate, N-ethyl-2-pyrrolidone, ethyl 3-ethoxypropionate and propylene glycol monobutyl ether, N-methyl-2-pyrrolidone, ethyl 3-ethoxypropionate and diethylene glycol monopropyl ether, N-ethyl-2-pyrrolidone, ethyl 3-ethoxypropionate and diethylene glycol monopropyl ether, N-methyl-2-pyrrolidone and ethylene glycol monobutyl ether acetate, N-ethyl-2-pyrrolidone and dipropylene glycol dimethyl ether, N,N-dimethyl lactamide and ethylene glycol monobutyl ether, N,N-dimethyl lactamide and propylene glycol diacetate, N-ethyl-2-pyrrolidone and diethylene glycol diethyl ether, N-ethyl-2-pyrrolidone, diethylene glycol monoethyl ether and butyl cellosolve acetate, N-methyl-2-pyrrolidone and diethylene glycol monomethyl ether and butyl cellosolve acetate, N,N-dimethyl lactamide and diethylene glycol diethyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone, 4-hydroxy-4-methyl-2-pentanone and diethylene glycol diethyl ether, N-ethyl-2-pyrrolidone, N-methyl-2-pyrrolidone and 4-hydroxy-4-methyl-2-pentanone, N-ethyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone and propylene glycol monobutyl ether,N-methyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone, and diisobutyl ketone, N-methyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone, and dipropylene glycol monomethyl ether, N-methyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone, and propylene glycol monobutyl ether, N-methyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone, and propylene glycol diacetate, N-ethyl-2-pyrrolidone, and 4-hydroxy-4-methyl -2-pentanone and dipropylene glycol dimethyl ether, γ-butyrolactone, 4-hydroxy-4-methyl-2-pentanone and diisobutyl ketone, γ-butyrolactone, 4-hydroxy-4-methyl-2-pentanone and propylene glycol diacetate, N-methyl-2-pyrrolidone, γ-butyrolactone, propylene glycol monobutyl ether and diisobutyl ketone, N-methyl-2-pyrrolidone, γ-butyrolactone, propylene glycol monobutyl ether and diisopropyl ether, N-methyl-2-pyrrolidone N-methyl-2-pyrrolidone, γ-butyrolactone, propylene glycol monobutyl ether, and diisobutylcarbinol, N-methyl-2-pyrrolidone, γ-butyrolactone, and dipropylene glycol dimethyl ether, N-methyl-2-pyrrolidone, propylene glycol monobutyl ether, and dipropylene glycol dimethyl ether, N-ethyl-2-pyrrolidone, propylene glycol monobutyl ether, and dipropylene glycol monomethyl ether, N-ethyl-2-pyrrolidone, diethylene glycol diethyl ether, and dipropylene glycol monomethyl ether, N-ethyl-2-pyrrolidone, propylene glycol monobutyl ether, and propylene glycol diacetate, N-ethyl-2-pyrrolidone, propylene glycol monobutyl ether, and diisobutyl ketone, N-ethyl-2-pyrrolidone, γ-butyrolactone, and diisobutyl ketone, N-ethyl-2-pyrrolidone, N,N-dimethyl lactamide, and diisobutyl ketone, N-methyl-2-pyrrolidone, ethylene glycol monobutyl ether, and ethylene glycol monobutyl ether acetate,Examples include γ-butyrolactone, ethylene glycol monobutyl ether acetate, and dipropylene glycol dimethyl ether, N-ethyl-2-pyrrolidone, ethylene glycol monobutyl ether acetate, and propylene glycol dimethyl ether, N-methyl-2-pyrrolidone, 4-methyl-2-pentyl acetate, and ethylene glycol monobutyl ether, and N-methyl-2-pyrrolidone, cyclohexanone, and propylene glycol monomethyl ether.

[0069] The solids concentration of 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% by mass. From the viewpoint of forming a uniform, defect-free coating film, a concentration of 1% by mass or more is preferred, and from the viewpoint of the storage stability of the solution, a concentration of 10% by mass or less is preferred. A particularly preferred solids concentration is 2 to 8% by mass. The solids concentration range may be appropriately selected depending on the method used to apply the liquid crystal aligning agent to the substrate. For example, when spin coating is performed, a solids concentration of 1.5 to 4.5% by mass is particularly preferred. When using a printing method, a solids concentration of 3 to 9% by mass is particularly preferred, thereby resulting in a solution viscosity of 12 to 50 mPa·s. When using an inkjet method, a solids concentration of 1 to 5% by mass is particularly preferred, thereby resulting in a solution viscosity of 3 to 15 mPa·s. The temperature when preparing the liquid crystal aligning agent is preferably 10 to 50°C, more preferably 20 to 30°C. The concentration of the polymer component in the liquid crystal aligning agent can be appropriately changed depending on the thickness of the coating film to be formed. From the viewpoint of forming a uniform and defect-free coating film, the concentration of the polymer component in the liquid crystal aligning agent (total concentration of polymers) is preferably 1% by mass or more, and from the viewpoint of solution storage stability, it is preferably 10% by mass or less. A particularly preferred polymer concentration is 2 to 8% by mass. From the viewpoint of suitably obtaining the effects of the present disclosure, the content of the polymer component (P) in the liquid crystal aligning agent (total amount of polymers constituting the polymer component (P)) is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, and even more preferably 50 parts by mass or more, relative to a total of 100 parts by mass of the polymer components contained in the liquid crystal aligning agent. When the liquid crystal aligning agent contains other polymers described below, the content of the polymer component (P) is preferably 99.9 parts by mass or less, more preferably 99 parts by mass or less, relative to a total of 100 parts by mass of the polymers contained in the liquid crystal aligning agent.

[0070] The liquid crystal aligning agent of the present invention may contain other components as necessary. Examples of such components include other polymers than the polymer (P) and the polyimide precursors (A) and (B); at least one compound selected from the group consisting of crosslinkable compounds having at least one substituent selected from an epoxy group, an isocyanate group, an oxetanyl group, a cyclocarbonate group, a blocked isocyanate group, a hydroxy group, and an alkoxy group, and a crosslinkable compound having a polymerizable unsaturated group; a functional silane compound; a metal chelate compound; a curing accelerator; a surfactant; an antioxidant; a sensitizer; a preservative; a compound for adjusting the dielectric constant or electrical resistance of the liquid crystal alignment film; and a compound for promoting imidization.

[0071] Specific examples of other polymers include polymers selected from the group consisting of polysiloxane, polyester, polyamide, polyurea, polyurethane, polyorganosiloxane, cellulose derivatives, polyacetal, polystyrene derivatives, poly(styrene-maleic anhydride) copolymer, poly(isobutylene-maleic anhydride) copolymer, poly(vinyl ether-maleic anhydride) copolymer, poly(styrene-phenylmaleimide) derivative, and poly(meth)acrylate.

[0072] Specific examples of poly(styrene-maleic anhydride) copolymers include SMA1000, 2000, and 3000 (manufactured by Cray Valley) and GSM301 (manufactured by Gifu Ceramics Manufacturing Co., Ltd.). Specific examples of poly(isobutylene-maleic anhydride) copolymers include ISOBAN-600 (manufactured by Kuraray Co., Ltd.). Specific examples of poly(vinyl ether-maleic anhydride) copolymers include Gantrez AN-139 (methyl vinyl ether maleic anhydride resin, manufactured by Ashland). One type of other polymer may be used alone, or two or more types may be used in combination. The content of the other polymer is preferably 90 parts by mass or less, and more preferably 80 parts by mass or less, relative to a total of 100 parts by mass of the polymers contained in the liquid crystal aligning agent. Furthermore, the content of the other polymer is preferably 0.1 parts by mass or more, and more preferably 1 part by mass or more, relative to a total of 100 parts by mass of the polymers contained in the liquid crystal aligning agent.

[0073] Specific preferred examples of the crosslinkable compound include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl ether, and the like. bisphenol A epoxy resins such as Epicoat 828 (manufactured by Mitsubishi Chemical Corporation), bisphenol F epoxy resins such as Epicoat 807 (manufactured by Mitsubishi Chemical Corporation), hydrogenated bisphenol A epoxy resins such as YX-8000 (manufactured by Mitsubishi Chemical Corporation), biphenyl skeleton-containing epoxy resins such as YX6954BH30 (manufactured by Mitsubishi Chemical Corporation), phenol novolac epoxy resins such as EPPN-201 (manufactured by Nippon Kayaku Co., Ltd.), and (o, m, p-) epoxy resins such as EOCN-102S (manufactured by Nippon Kayaku Co., Ltd.). Cresol novolac epoxy resins, triglycidyl isocyanurates such as TEPIC (manufactured by Nissan Chemical Industries, Ltd.), alicyclic epoxy resins such as Celloxide 2021P (manufactured by Daicel Corporation), compounds containing a tertiary nitrogen atom such as N,N,N',N'-tetraglycidyl-m-xylylenediamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, or N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, and oxy groups such as tetrakis(glycidyloxymethyl)methane. Compounds having two or more silanyl groups; compounds having two or more oxetanyl groups described in paragraphs

[0170] to

[0175] of WO 2011 / 132751; compounds having a blocked isocyanate group such as Coronate AP Stable M, Coronate 2503, 2515, 2507, 2513, 2555, Millionate MS-50 (all manufactured by Tosoh Corporation), and Takenate B-830, B-815N, B-820NSU, B-842N, B-846N, B-870N, B-874N, and B-882N (all manufactured by Mitsui Chemicals, Inc.);Compounds having an oxazoline group such as 2,2'-bis(2-oxazoline), 2,2'-bis(4-methyl-2-oxazoline), 2,2'-bis(5-methyl-2-oxazoline), 1,2,4-tris(2-oxazolinyl)-benzene, and EPOCROS (manufactured by Nippon Shokubai Co., Ltd.); compounds having a cyclocarbonate group described in paragraphs

[0025] to

[0030] and

[0032] of WO2011 / 155577; N,N,N',N'-tetrakis(2-hydroxyethyl)adipamide, 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethoxyphenyl)propane, 2,2-bis(4-hydroxy-3,5-dihydro compounds having a hydroxy group or an alkoxy group, such as (hydroxymethylphenyl)-1,1,1,3,3,3-hexafluoropropane; and compounds represented by glycerin mono(meth)acrylate, glycerin di(meth)acrylate (1,2-,1,3-diglycerolate mixture), glycerin tris(meth)acrylate, glycerin 1,3-diglycerolate di(meth)acrylate, pentaerythritol tri(meth)acrylate, diethylene glycol mono(meth)acrylate, triethylene glycol mono(meth)acrylate, tetraethylene glycol mono(meth)acrylate, pentaethylene glycol mono(meth)acrylate, and hexaethylene glycol mono(meth)acrylate. The content of the crosslinkable compound is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, per 100 parts by mass of the polymer component contained in the liquid crystal aligning agent;

[0074] Examples of the compound for adjusting the dielectric constant or electrical resistance include monoamines having a nitrogen atom-containing aromatic heterocycle such as 3-picolylamine. The content of the monoamine having a nitrogen atom-containing aromatic heterocycle is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, per 100 parts by mass of the polymer component contained in the liquid crystal aligning agent.

[0075] Specific preferred examples of the functional silane compound include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and 3-glycidoxypropylmethyldimethoxysilane. , 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, tris[3-(trimethoxysilyl)propyl]isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, etc. The content of the functional silane compound is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, per 100 parts by mass of the polymer component contained in the liquid crystal alignment agent.

[0076] The compound for promoting the imidization is preferably a compound having a basic site (e.g., a primary amino group, an aliphatic heterocycle (e.g., a pyrrolidine skeleton), an aromatic heterocycle (e.g., an imidazole ring, an indole ring), or a guanidino group) (excluding the crosslinkable compound and the adhesion aid), or a compound that generates the basic site upon baking. A more preferred example is a compound that generates the basic site upon baking, and preferred specific examples include amino acids in which some or all of the basic sites of the amino acid are protected. Examples of protecting groups for the basic sites of the amino acids include carbamate protecting groups such as a Boc group. Specific examples of the amino acids include glycine, alanine, cysteine, methionine, asparagine, glutamine, valine, leucine, phenylalanine, tyrosine, tryptophan, proline, hydroxyproline, arginine, histidine, lysine, and ornithine. A more preferred specific example of the compound for promoting imidization is N-α-(9-fluorenylmethoxycarbonyl)-N-τ-(tert-butoxycarbonyl)-L-histidine. The content of the compound for promoting imidization contained in the liquid crystal aligning agent of the present invention is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, and even more preferably 5 to 20 parts by mass, relative to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent.

[0077] (Liquid Crystal Alignment Film and Liquid Crystal Display Element) The liquid crystal display element according to the present invention comprises a liquid crystal alignment film formed using the liquid crystal aligning agent described above. The liquid crystal alignment film of the present invention can be produced, for example, by a method including the following steps (1) and (2) or a method including the following steps (1) to (3). The operation mode of the liquid crystal display element is not particularly limited, and it can be applied to various operation modes, such as the TN mode, STN mode, vertical alignment mode (including the VA-MVA mode, the VA-PVA mode, etc.), in-plane switching mode (IPS mode, FFS mode), and optically compensated bend mode (OCB mode).

[0078] The liquid crystal display element of the present invention can be manufactured by, for example, a method including the following steps (1) to (4), a method including steps (1) to (2) and (4), a method including steps (1) to (3), (4-2) and (4-4), or a method including steps (1) to (3), (4-3) and (4-4). One embodiment of the liquid crystal display element of the present invention is a liquid crystal display element having a liquid crystal alignment film formed by a method for manufacturing a liquid crystal alignment film including the following steps (1) to (2) or steps (1) to (3).

[0079] <Step (1): Applying a Liquid Crystal Alignment Agent to a Substrate> Step (1) is a step of applying a liquid crystal alignment agent to a substrate. A specific example of step (1) is as follows: The liquid crystal alignment agent is applied to one side of a substrate having a patterned transparent conductive film by an appropriate application method, such as a roll coater method, a spin coat method, a printing method, or an inkjet method. The substrate material is not particularly limited as long as it is highly transparent; glass, silicon nitride, and plastics such as acrylic and polycarbonate can also be used. In addition, in a reflective liquid crystal display element, an opaque material such as a silicon wafer can be used for only one substrate. In this case, a light-reflecting material such as aluminum can also be used for the electrode. Furthermore, when manufacturing an IPS or FFS liquid crystal display element, a substrate having an electrode made of a comb-shaped patterned transparent conductive film or metal film and an opposing substrate having no electrode are used. An IPS substrate, which is a comb electrode substrate used in an IPS-mode liquid crystal display element, has, for example, a base material, a plurality of linear electrodes formed on the base material and arranged in a comb-teeth pattern, and a liquid crystal alignment film formed on the base material so as to cover the linear electrodes. Meanwhile, an FFS substrate, which is a comb electrode substrate used in an FFS-mode liquid crystal display element, has, for example, a base material, a surface electrode formed on the base material, an insulating film formed on the surface electrode, a plurality of linear electrodes formed on the insulating film and arranged in a comb-teeth pattern, and a liquid crystal alignment film formed on the insulating film so as to cover the linear electrodes.

[0080] Examples of a method for applying the liquid crystal alignment agent to a substrate and forming a film include screen printing, offset printing, flexographic printing, an inkjet method, and a spray method. Among these, the application and film formation method by the inkjet method is preferably used.

[0081] <Step (2): Step of Baking the Applied Liquid Crystal Alignment Agent> Step (2) is a step of baking the liquid crystal alignment agent applied to the substrate to form a film. Specific examples of step (2) are as follows. After applying the liquid crystal alignment agent to the substrate in step (1), the solvent can be evaporated or a polyimide precursor, such as polyamic acid, can be thermally imidized using a heating means such as a hot plate, a hot air circulation oven, or an IR (infrared) oven. The drying and baking steps after applying the liquid crystal alignment agent can be performed at any temperature and for any time, and may be performed multiple times. The temperature at which the liquid crystal alignment agent is baked can be, for example, 40 to 180°C. From the perspective of shortening the process, it may be performed at 40 to 150°C. The baking time is not particularly limited, but may be 1 to 10 minutes or 1 to 5 minutes. When thermal imidization of a polyimide precursor, such as polyamic acid, is carried out, a baking step may be added after the above step, for example, at 150 to 300°C or 150 to 250°C. The baking time is not particularly limited, but examples include baking times of 5 to 40 minutes or 5 to 30 minutes. If the film-like material after baking is too thin, the reliability of the liquid crystal display element may decrease, so the film thickness is preferably 5 to 300 nm, more preferably 10 to 200 nm.

[0082] <Step (3): Alignment Treatment of the Film Obtained in Step (2)> Step (3) is a step of, optionally, aligning the film obtained in Step (2). That is, in horizontal alignment mode liquid crystal display elements such as IPS mode or FFS mode, the coating film is subjected to an alignment ability imparting treatment. On the other hand, in vertical alignment mode liquid crystal display elements such as VA mode or PSA mode, the formed coating film can be used as a liquid crystal alignment film as is, or the coating film may be subjected to an alignment ability imparting treatment. Alignment treatment methods for liquid crystal alignment films include rubbing alignment treatment and photoalignment treatment. Photoalignment treatment methods include irradiating the surface of the film-like material with radiation, preferably polarized in a certain direction, and then preferably performing a heat treatment to impart liquid crystal alignment (also referred to as liquid crystal alignment ability). The radiation can be ultraviolet light or visible light having a wavelength of 100 to 800 nm. Among these, ultraviolet light having a wavelength of 100 to 400 nm is preferred, and more preferably 200 to 400 nm is more preferred.

[0083] The radiation dose is 1 to 10,000 mJ / cm ２ is preferable, and among these, 100 to 5,000 mJ / cm ２ is more preferable. Furthermore, when irradiating with radiation, the substrate having the film-like material may be irradiated while being heated at 50 to 250°C in order to improve the liquid crystal alignment. The liquid crystal alignment film thus prepared can stably align liquid crystal molecules in a specific direction. Examples of light sources that can be used for the irradiation light include low-pressure mercury lamps, high-pressure mercury lamps, deep UV lamps, deuterium lamps, metal halide lamps, argon resonance lamps, xenon lamps, mercury-xenon lamps, excimer lasers (e.g., KrF excimer lasers), fluorescent lamps, LED lamps, halogen lamps (e.g., sodium lamps), and microwave-excited electrodeless lamps. Furthermore, when polarized light is used as the irradiation light, a higher extinction ratio of polarized light can impart higher anisotropy. Therefore, in the case of ultraviolet light, for example, the extinction ratio of polarized ultraviolet light is more preferably 10:1 or more, and even more preferably 20:1 or more.

[0084] Furthermore, the coating film irradiated with polarized radiation or the coating film subjected to rubbing alignment treatment by the above method may be subjected to a contact treatment using water or a solvent. Furthermore, the film subjected to the above alignment treatment may be subjected to a heat treatment without being subjected to a contact treatment. Furthermore, the film subjected to the above contact treatment may be further subjected to a heat treatment.

[0085] The solvent used in the contact treatment is not particularly limited as long as it dissolves the decomposition products generated from the film-like material by irradiation. Specific examples include water, methanol, ethanol, 2-propanol, acetone, methyl ethyl ketone, 1-methoxy-2-propanol, 1-methoxy-2-propanol acetate, butyl cellosolve, ethyl lactate, methyl lactate, diacetone alcohol, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propyl acetate, butyl acetate, and cyclohexyl acetate. The solvent may be used alone or in combination of two or more.

[0086] The temperature for the heat treatment of the coating film irradiated with radiation or the film that has been contact-treated is preferably 50 to 300° C., more preferably 120 to 300° C., even more preferably 150 to 300° C., and most preferably 150 to 250° C. The heat treatment time is preferably 1 to 30 minutes.

[0087] <Step (4): Step of preparing a liquid crystal cell> Two substrates on which a liquid crystal alignment film has been formed are prepared as described above, and a liquid crystal is placed between the two substrates arranged opposite each other. Specifically, the following two methods can be mentioned. In the first method, the two substrates are first arranged opposite each other with a gap (cell gap) between them so that the liquid crystal alignment films face each other. Next, the peripheries of the two substrates are bonded together using a sealant, and a liquid crystal composition is injected into the substrate surfaces and the cell gap defined by the sealant to contact the film surface, and then the injection hole is sealed.

[0088] The second method is called the ODF (One Drop Fill) method. A UV-curable sealant, for example, is applied to a predetermined location on one of two substrates on which a liquid crystal alignment film has been formed, and a liquid crystal composition is then dropped onto several predetermined locations on the liquid crystal alignment film. The other substrate is then attached so that the liquid crystal alignment film faces the other substrate, and the liquid crystal composition is spread over the entire surface of the substrate and brought into contact with the film surface. The entire surface of the substrate is then irradiated with UV light to cure the sealant. In either method, it is desirable to further heat the substrate to a temperature at which the liquid crystal composition assumes an isotropic phase and then slowly cool it to room temperature to remove flow alignment that occurs during liquid crystal filling. If the coating film is subjected to a rubbing alignment treatment, the two substrates are positioned opposite each other so that the rubbing directions of the coating films are at a predetermined angle to each other, for example, perpendicular or antiparallel. For example, an epoxy resin containing a curing agent and aluminum oxide spheres as spacers can be used as the sealant. The liquid crystal composition is not particularly limited, and may be a composition containing at least one liquid crystal compound (liquid crystal molecule), such as a liquid crystal composition exhibiting a nematic phase (hereinafter also referred to as nematic liquid crystal), a liquid crystal exhibiting a smectic phase, or a liquid crystal composition exhibiting a cholesteric phase. Among these, nematic liquid crystal is preferred. Furthermore, various liquid crystal compositions having positive or negative dielectric anisotropy may be used. Hereinafter, a liquid crystal composition having a positive dielectric anisotropy is also referred to as a positive liquid crystal, and a liquid crystal composition having a negative dielectric anisotropy is also referred to as a negative liquid crystal. The liquid crystal composition may contain a liquid crystal compound having a fluorine atom, a hydroxy group, an amino group, a fluorine atom-containing group (e.g., a trifluoromethyl group), a cyano group, an alkyl group, an alkoxy group, an alkenyl group, an isothiocyanate group, a heterocycle, a cycloalkane, a cycloalkene, a steroid skeleton, a benzene ring, or a naphthalene ring, or may contain a compound having two or more rigid moieties (mesogenic skeletons) that exhibit liquid crystallinity in the molecule (e.g., a bimesogenic compound in which two rigid biphenyl structures or terphenyl structures are linked by an alkyl group). Furthermore, the liquid crystal composition may further contain an additive from the viewpoint of improving liquid crystal alignment properties.Such additives include photopolymerizable monomers such as compounds having a polymerizable group (e.g., a (meth)acryloyl group); optically active compounds (e.g., S-811 manufactured by Merck Co., Ltd.); antioxidants; ultraviolet absorbers; dyes; antifoaming agents; polymerization initiators; or polymerization inhibitors. Positive liquid crystals include ZLI-2293, ZLI-4792, MLC-2003, MLC-2041, MLC-3019, and MLC-7081 manufactured by Merck Co., Ltd. Negative liquid crystals include MLC-6608, MLC-6609, MLC-6610, MLC-7026, and MLC-7026-100 manufactured by Merck Co., Ltd. Furthermore, an example of a liquid crystal containing a compound having a polymerizable group is MLC-3023 manufactured by Merck Co., Ltd.

[0089] The liquid crystal aligning agent of the present invention is also preferably used in a liquid crystal display element (PSA-type liquid crystal display element) manufactured by a process of: having a liquid crystal layer between a pair of substrates equipped with electrodes, disposing a liquid crystal composition containing a polymerizable compound that polymerizes by at least one of active energy rays and heat between the pair of substrates, and polymerizing the polymerizable compound by at least one of irradiation with active energy rays and heating while applying a voltage between the electrodes. The liquid crystal aligning agent of the present invention is also preferably used in a liquid crystal display element (SC-PVA-type liquid crystal display element) manufactured by a process of having a liquid crystal layer between a pair of substrates equipped with electrodes, disposing a liquid crystal alignment film between the pair of substrates that contains a polymerizable group that polymerizes by at least one of active energy rays and heat, and applying a voltage between the electrodes.

[0090] <Step (4-2): In the case of a PSA-type liquid crystal display element> This step is carried out in the same manner as in the above step (4), except that a liquid crystal composition containing a polymerizable compound is injected or dropped. Examples of the polymerizable compound include polymerizable compounds having one or more polymerizable unsaturated groups, such as an acrylate group or a methacrylate group, in the molecule.

[0091] <Step (4-3): In the Case of an SC-PVA-Type Liquid Crystal Display Element> A method for producing a liquid crystal display element may be employed, in which a process similar to that described in (4) above is followed by a step of irradiating with ultraviolet light, as described below. This method, similar to the production of a PSA-type liquid crystal display element, allows for the production of a liquid crystal display element with excellent response speed with a low light exposure dose. The compound having a polymerizable group may be a compound having one or more of the above-described polymerizable unsaturated groups in its molecule, and its content is preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, per 100 parts by mass of the polymer component contained in the liquid crystal aligning agent. Furthermore, the polymerizable group may be contained in the polymer used in the liquid crystal aligning agent. Examples of such polymers include polymers obtained by reacting a diamine component containing a diamine having the above-described photopolymerizable group at its terminal.

[0092] <Step (4-4): Step of Irradiating Ultraviolet Light> The liquid crystal cell is irradiated with light while a voltage is applied between the conductive films of the pair of substrates obtained in step (4-2) or (4-3) above. The voltage applied here can be, for example, a direct current or alternating current of 5 to 50 V. The light to be irradiated can be, for example, ultraviolet light and visible light containing light with a wavelength of 150 to 800 nm, but ultraviolet light containing light with a wavelength of 300 to 400 nm is preferred. The light source for the irradiation light can be, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, or an excimer laser. The light irradiation dose is preferably 1,000 to 200,000 J / m ２ and more preferably 1,000 to 100,000 J / m ２ is.

[0093] A liquid crystal display element can be obtained by attaching a polarizing plate to the outer surface of the liquid crystal cell as needed. Examples of the polarizing plate to be attached to the outer surface of the liquid crystal cell include a polarizing film called an "H film" made by stretching and aligning polyvinyl alcohol and absorbing iodine, sandwiched between cellulose acetate protective films, and a polarizing plate made of the H film itself.

[0094] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. The abbreviations for compounds and solvents are as follows.

[0095] (Organic solvent) NMP: N-methyl-2-pyrrolidone GBL: γ-butyrolactone BCS: Ethylene glycol monobutyl ether (Compound (C)) D-Limonene (manufactured by Sigma-Aldrich) L-Limonene (manufactured by Sigma-Aldrich) DL-Limonene (manufactured by Tokyo Chemical Industry Co., Ltd.) DL-Menthol (manufactured by Tokyo Chemical Industry Co., Ltd.) L-Menthol (manufactured by Tokyo Chemical Industry Co., Ltd.) D-Menthol (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0096] (Diamines) DA-1 to DA-16: Compounds represented by the following structural formulas (DA-1) to (DA-16), respectively. (Tetracarboxylic acid derivatives) CA-1 to CA-6: Compounds represented by the following structural formulas (CA-1) to (CA-6), respectively. (Terminal modifier) ​​SA: Succinic anhydride. (Additives) AD-1: Compound represented by the following structural formula (AD-1). AD-2: Compound represented by the following structural formula (AD-2). AD-3: 3-Glycidoxypropyltriethoxysilane. AD-4: 3-Aminopropyltriethoxysilane. AD-5: N-α-(9-fluorenylmethoxycarbonyl)-N-τ-(tert-butoxycarbonyl)-L-histidine. AD-6: Compound represented by the following structural formula (AD-6).

[0097] <Viscosity> In the synthesis examples, the viscosity of the polymer solution was measured using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.) with a sample amount of 1.1 mL, a cone rotor TE-1 (1°34', R24), and a temperature of 25°C.

[0098] <Measurement of Imidization Ratio of Polyimide> The imidization ratio of the polyimide in the synthesis examples was measured as follows. 30 mg of polyimide powder was placed in an NMR (nuclear magnetic resonance) sample tube (NMR sampling tube standard, φ5 (Kusano Scientific Co., Ltd.)), and deuterated dimethyl sulfoxide (DMSO-d6, 0.05 mass% TMS (tetramethylsilane) mixture) (0.53 mL) was added. Complete dissolution was achieved by applying ultrasound. This solution was subjected to 500 MHz proton NMR measurement using an NMR measurement device (JNW-ECA500) (JEOL Datum Co., Ltd.). The proton derived from the structure that remains unchanged before and after imidization was determined as the reference proton, and the peak integrated value of this proton and the peak integrated value of the proton derived from the NH group of the amic acid that appears around 9.5 ppm to 10.0 ppm were used to calculate the imidization ratio according to the following formula: Imidization rate (%)=(1−α×x / y)×100 In the above formula, x is the integrated value of the proton peak derived from the NH group of the amic acid, y is the integrated value of the peak of the reference proton, and α is the ratio of the number of reference protons to one NH group proton of the amic acid in the case of polyamic acid (imidization rate 0%).

[0099] [Synthesis of Polymer] (Synthesis Example 1) 2.16 g (20.0 mmol) of DA-5, 7.33 g (30.0 mmol) of DA-2, 9.61 g (30.0 mmol) of DA-6, and 7.97 g (20.0 mmol) of DA-10 were placed in a 500 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and 311.3 g of NMP was added, followed by stirring and dissolution while feeding nitrogen. While stirring this diamine solution, 20.85 g (93.0 mmol) of CA-2 was added, and 40.1 g of NMP was added so that the solids concentration became 12% by mass, and the mixture was stirred for 24 hours while heating at 40 ° C. to obtain a polymer solution (polymer-1) (viscosity: 201 mPa s).

[0100] Synthesis Example 2 A 100 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube was charged with 4.14 g (20.8 mmol) of DA-8 and 0.89 g (5.85 mmol) of DA-9, and 44.4 g of NMP was added. The mixture was stirred and dissolved while supplying nitrogen. While stirring this diamine solution, 7.27 g (24.7 mmol) of CA-4 was added, and 45.1 g of NMP was further added so that the solids concentration became 12% by mass. The mixture was stirred for 24 hours under a nitrogen atmosphere while heating at 60°C to obtain a polymer solution (polymer-2) (viscosity: 398 mPa s).

[0101] (Synthesis Example 3) 7.45 g (26.0 mmol) of DA-1 was placed in a 100 ml four-neck flask equipped with a stirrer and a nitrogen inlet tube, and 67.0 g of NMP was added. The mixture was stirred and dissolved while supplying nitrogen. 4.86 g (22.3 mmol) of CA-3 was added to this diamine solution while stirring under water cooling, and 23.3 g of NMP was added so that the solids concentration became 12% by mass. The mixture was stirred for 20 hours under a nitrogen atmosphere while heating at 50°C to obtain a polymer solution (polymer-3) (viscosity: 530 mPa s).

[0102] (Synthesis Example 4) 0.99 g (5.00 mmol) of DA-3 and 3.99 g (20.0 mmol) of DA-8 were placed in a 100 ml four-neck flask equipped with a stirrer and a nitrogen inlet tube, and 57.2 g of NMP was added. The mixture was stirred and dissolved while feeding nitrogen. 1.50 g (5.00 mmol) of CA-5 and 1.07 g of NMP were added while stirring this diamine solution under water cooling, and the mixture was stirred for 3 hours under a nitrogen atmosphere and water cooling. Thereafter, 3.53 g (18.0 mmol) of CA-1 was added, and 31.8 g of NMP was added so that the solids concentration was 10% by mass, and the mixture was stirred again under a nitrogen atmosphere and water cooling for 3 hours to obtain a polymer solution (polymer-4) (viscosity: 165 mPa s).

[0103] (Synthesis Example 5) In a 500 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, 3.24 g (30.0 mmol) of DA-5, 7.33 g (30.0 mmol) of DA-2, 3.00 g (20.0 mmol) of DA-11, and 6.83 g (20.0 mmol) of DA-7 were taken, and 234.7 g of NMP was added, and the mixture was stirred and dissolved while feeding nitrogen. While stirring this diamine solution, 20.85 g (93.0 mmol) of CA-2 was added, and 67.9 g of NMP was added so that the solids concentration became 12% by mass, and the mixture was stirred for 24 hours while heating at 40 ° C. to obtain a polymer solution (polymer-5) (viscosity: 451 mPa s).

[0104] Synthesis Example 6 Into a 500 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, 17.90 g (60.0 mmol) of DA-4 and 6.01 g (40.0 mmol) of DA-11 were placed, and 275 g of NMP was added. The mixture was stirred and dissolved while supplying nitrogen. While stirring this diamine solution, 18.43 g (94.0 mmol) of CA-1 was added, and 35.5 g of NMP was further added so that the solids concentration became 12% by mass. The mixture was stirred at room temperature for 24 hours to obtain a polymer solution (polymer-6) (viscosity: 503 mPa s).

[0105] (Synthesis Example 7) Into a 500 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, 2.60 g (24.0 mmol) of DA-5, 5.86 g (24.0 mmol) of DA-2, 4.13 g (16.0 mmol) of DA-12, and 5.46 g (16.0 mmol) of DA-7 were weighed out, and 233.38 g of NMP was added, followed by stirring and dissolution while feeding nitrogen. While stirring this diamine solution, 17.31 g (77.2 mmol) of CA-2 was added, and further, NMP was added so that the solids concentration was 12% by mass, and the mixture was stirred for 4 hours while heating at 40 ° C. to obtain a polymer solution (polymer-7) (viscosity: 431 mPa s).

[0106] Synthesis Example 8: 50 g of the resulting polymer solution (Polymer-7) was weighed into a 100 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and 25 g of NMP was added and stirred for 30 minutes. To the resulting polyamic acid solution, 4.16 g of acetic anhydride and 1.07 g of pyridine were added, and the mixture was heated at 55°C for 2 hours and 30 minutes to perform chemical imidization. The resulting reaction solution was poured into 300 mL of methanol with stirring, and the precipitate was collected by filtration. Subsequently, the precipitate was washed three times with 300 mL of methanol. The resulting resin powder was then dried at 60°C for 12 hours to obtain a polyimide resin powder. The imidization rate of this polyimide resin powder was 70%. 4.80 g of the obtained polyimide resin powder was weighed into a 100 mL Erlenmeyer flask containing a stirrer, and 35.20 g of NMP was added thereto. The mixture was stirred at 70°C for 12 hours to dissolve the polyimide resin powder, thereby obtaining a polymer solution (Polymer-8) having a solid content concentration of 12% by mass.

[0107] Synthesis Example 9 3.19 g (16.0 mmol) of DA-8 and 0.61 g (4.00 mmol) of DA-9 were weighed into a 100 mL recovery flask equipped with a stirrer and a nitrogen inlet tube, and 33.3 g of NMP was added. The mixture was stirred and dissolved while supplying nitrogen. While stirring this diamine solution under water cooling, 1.25 g (5.0 mmol) of CA-6 was added, and then 3.7 g of NMP was added, and the mixture was stirred at 50 ° C. for 2 hours under a nitrogen atmosphere. Further, 32.0 g of NMP was added, followed by 5.41 g (18.4 mmol) of CA-4, and then 7.7 g of NMP was added. The mixture was stirred at 70 ° C. for 12 hours under a nitrogen atmosphere to obtain a polyamic acid solution (polymer-9) (viscosity: 320 mPa s).

[0108] (Synthesis Example 10) DA-3 (2.78 g, 14.0 mmol), DA-13 (2.28 g, 6.00 mmol) and NMP (20.2 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and the mixture was stirred at room temperature for 0.5 hours while supplying nitrogen. Thereafter, CA-6 (2.50 g, 10.00 mmol) and NMP (10.0 g) were added, and the mixture was stirred at 60 ° C. for 3 hours. Thereafter, CA-1 (1.91 g, 9.76 mmol) and NMP (7.66 g) were added, and the mixture was stirred at 40 ° C. for 3 hours to obtain a polyamic acid solution (polymer-10) having a solids concentration of 20% by mass (viscosity: 740 mPa s).

[0109] (Synthesis Example 11) DA-3 (1.39 g, 7.00 mmol), DA-15 (0.991 g, 3.00 mmol), DA-14 (0.969 g, 4.00 mmol), DA-16 (2.61 g, 6.00 mmol) and NMP (23.8 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and the mixture was stirred at room temperature for 0.5 hours while supplying nitrogen. Thereafter, CA-6 (2.50 g, 10.00 mmol) and NMP (10.0 g) were added, and the mixture was stirred at 60 ° C. for 3 hours. Thereafter, CA-1 (1.91 g, 9.74 mmol) and NMP (7.64 g) were added, and the mixture was stirred at 40 ° C. for 3 hours to obtain a polyamic acid solution (polymer-11) having a solids concentration of 20% by mass (viscosity: 710 mPa s).

[0110] Synthesis Example 12 30 g of the polyamic acid solution polymer-1 obtained in Synthesis Example 1 was placed in a 100 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and 0.05 g (0.5 mmol) of SA was added thereto. The mixture was stirred at room temperature for 24 hours to obtain a polyamic acid solution containing a non-amino terminal structure (polymer-12).

[0111] Synthesis Example 13: 13.71 g (80.0 mmol) of DA-8 and 2.62 g (20.0 mmol) of DA-9 were placed in a 500 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and 159.1 g of NMP was added. The mixture was stirred and dissolved while supplying nitrogen. While stirring this diamine solution, 5.38 g (25.0 mmol) of CA-4 was added, and the mixture was heated to 50°C and stirred for 2 hours. The mixture was then cooled to room temperature in a water bath, and 17.97 g (71.0 mmol) of CA-6 was added. 131.7 g of NMP was then added, and the mixture was stirred in a water bath for 30 minutes. The mixture was then heated to 70°C and stirred for 2 hours to obtain a polyamic acid (polymer-13). The viscosity of this polyamic acid was 315 mPa s.

[0112] The specifications of the polymers obtained in the above synthesis examples are shown in Tables 1 and 2. In the tables, the parenthesized numbers for the tetracarboxylic acid components indicate the amount (parts by mole) of each tetracarboxylic dianhydride used relative to 100 parts by mole of the total amount of the tetracarboxylic acid components used in the polymerization. The parenthesized numbers for the diamine components indicate the amount (parts by mole) of each diamine used relative to 100 parts by mole of the total amount of the diamine components used in the polymerization.

[0113]

[0114]

[0115] [Preparation of Liquid Crystal Alignment Agent] (Example 1) Into a 30 mL Erlenmeyer flask containing a stirrer, the solution (4.58 g) of the polymer (polymer-1) obtained in Synthesis Example 1 and the solution (4.58 g) of the polymer (polymer-2) obtained in Synthesis Example 2 were weighed out, and NMP (3.03 g), BCS (5.00 g), D-limonene (1.00 g), a 10 mass % NMP solution of AD-1 (0.55 g), a 1 mass % NMP solution of AD-3 (1.10 g), and AD-5 (0.15 g) were added, and the mixture was stirred at room temperature for 2 hours to obtain a liquid crystal alignment agent (A-1).

[0116] Example 2 Into a 30 mL Erlenmeyer flask containing a stirrer, the solution (4.58 g) of the polymer (polymer-1) obtained in Synthesis Example 1 and the solution (4.58 g) of the polymer (polymer-2) obtained in Synthesis Example 2 were weighed out, and NMP (3.03 g), BCS (5.00 g), L-limonene (1.00 g), a 10 mass % NMP solution of AD-1 (0.55 g), a 1 mass % NMP solution of AD-3 (1.10 g), and AD-5 (0.15 g) were added, and the mixture was stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent (A-2).

[0117] Example 3 In a 30 mL Erlenmeyer flask containing a stirrer, the solution (4.58 g) of the polymer (polymer-1) obtained in Synthesis Example 1 and the solution (4.58 g) of the polymer (polymer-2) obtained in Synthesis Example 2 were weighed out, and NMP (3.03 g), BCS (5.00 g), DL-limonene (1.00 g), a 10 mass % NMP solution of AD-1 (0.55 g), a 1 mass % NMP solution of AD-3 (1.10 g), and AD-5 (0.15 g) were added, and the mixture was stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent (A-3).

[0118] Example 4 Into a 30 mL Erlenmeyer flask containing a stirrer, the solution (4.58 g) of the polymer (polymer-1) obtained in Synthesis Example 1 and the solution (4.58 g) of the polymer (polymer-9) obtained in Synthesis Example 9 were weighed out, and NMP (3.03 g), BCS (5.80 g), D-limonene (0.20 g), a 10 mass % NMP solution of AD-2 (0.55 g), a 1 mass % NMP solution of AD-3 (1.10 g), and AD-5 (0.15 g) were added, and the mixture was stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent (A-4).

[0119] Example 5 Into a 30 mL Erlenmeyer flask containing a stirrer, a solution (3.67 g) of the polymer (polymer-5) obtained in Synthesis Example 5 and a solution (5.50 g) of the polymer (polymer-6) obtained in Synthesis Example 6 were weighed out, and NMP (2.83 g), BCS (4.00 g), D-limonene (2.00 g), a 10 mass % NMP solution (0.56 g) of AD-1, and a 1 mass % NMP solution (1.10 g) of AD-3 were added, and the mixture was stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent (A-5).

[0120] Example 6 Into a 30 mL Erlenmeyer flask containing a stirrer, a solution (3.67 g) of the polymer (polymer-5) obtained in Synthesis Example 5 and a solution (5.50 g) of the polymer (polymer-6) obtained in Synthesis Example 6 were weighed out, and NMP (2.83 g), BCS (4.00 g), L-limonene (2.00 g), a 10 mass % NMP solution (0.56 g) of AD-1, and a 1 mass % NMP solution (1.10 g) of AD-3 were added, and the mixture was stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent (A-6).

[0121] Example 7 In a 30 mL Erlenmeyer flask containing a stirrer, a solution (3.33 g) of the polymer (polymer-8) obtained in Synthesis Example 8 and a solution (5.00 g) of the polymer (polymer-2) obtained in Synthesis Example 2 were weighed out, and NMP (0.03 g), GBL (6.00 g), BCS (3.00 g), D-limonene (1.00 g), a 10 mass % NMP solution of AD-1 (0.45 g), a 1 mass % NMP solution of AD-3 (0.90 g), and AD-5 (0.09 g) were added, and the mixture was stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent (A-7).

[0122] Example 8 Into a 30 mL Erlenmeyer flask containing a stirrer, the solution (1.83 g) of the polymer (polymer-3) obtained in Synthesis Example 3 and the solution (8.80 g) of the polymer (polymer-4) obtained in Synthesis Example 4 were weighed, and NMP (3.24 g), BCS (3.00 g), D-limonene (1.00 g) and a 1 mass % NMP solution (0.96 g) of AD-4 were added, and the mixture was stirred at room temperature for 2 hours, thereby obtaining a liquid crystal aligning agent (A-8).

[0123] Example 9 The polyamic acid solution (polymer-10) (5.00 g) obtained in Synthesis Example 10 was weighed out, and NMP (4.00 g), BCS (10.00 g), and D-limonene (1.00 g) were added thereto, followed by stirring at room temperature for 2 hours, thereby obtaining a liquid crystal aligning agent (A-9).

[0124] Example 10 The polyamic acid solution (polymer-11) (5.00 g) obtained in Synthesis Example 11 was weighed out, and NMP (4.00 g), BCS (10.00 g), and D-limonene (1.00 g) were added thereto, followed by stirring at room temperature for 2 hours, thereby obtaining a liquid crystal aligning agent (A-10).

[0125] Comparative Example 1 Into a 30 mL Erlenmeyer flask containing a stirrer, the solution (4.58 g) of the polymer (polymer-1) obtained in Synthesis Example 1 and the solution (4.58 g) of the polymer (polymer-2) obtained in Synthesis Example 2 were weighed out, and NMP (3.03 g), BCS (6.00 g), a 10 mass % NMP solution of AD-1 (0.56 g), a 1 mass % NMP solution of AD-3 (1.10 g), and AD-5 (0.15 g) were added, and the mixture was stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent (B-1).

[0126] Comparative Example 2 Into a 30 mL Erlenmeyer flask containing a stirrer, the solution (5.42 g) of the polymer (polymer-1) obtained in Synthesis Example 1 and the solution (5.42 g) of the polymer (polymer-2) obtained in Synthesis Example 2 were weighed out, and NMP (1.03 g), BCS (6.00 g), a 10 mass % NMP solution of AD-1 (0.65 g), a 1 mass % NMP solution of AD-3 (1.30 g), and AD-5 (0.18 g) were added, and the mixture was stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent (B-2).

[0127] Comparative Example 3 Into a 30 mL Erlenmeyer flask containing a stirrer, a solution (4.58 g) of the polymer (polymer-1) obtained in Synthesis Example 1 and a solution (4.58 g) of the polymer (polymer-9) obtained in Synthesis Example 9 were weighed out, and NMP (3.03 g), BCS (6.00 g), a 10 mass % NMP solution of AD-2 (0.56 g), a 1 mass % NMP solution of AD-3 (1.10 g), and AD-5 (0.15 g) were added, followed by stirring at room temperature for 2 hours, thereby obtaining a liquid crystal aligning agent (B-3).

[0128] Comparative Example 4 Into a 30 mL Erlenmeyer flask containing a stirrer, a solution (3.67 g) of the polymer (polymer-5) obtained in Synthesis Example 5 and a solution (5.50 g) of the polymer (polymer-6) obtained in Synthesis Example 6 were weighed out, and NMP (3.03 g), BCS (6.00 g), a 10 mass % NMP solution (0.56 g) of AD-1, and a 1 mass % NMP solution (1.10 g) of AD-3 were added, and the mixture was stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent (B-4).

[0129] Comparative Example 5 Into a 30 mL Erlenmeyer flask containing a stirrer, a solution (3.33 g) of the polymer (polymer-8) obtained in Synthesis Example 8 and a solution (5.00 g) of the polymer (polymer-2) obtained in Synthesis Example 2 were weighed out, and NMP (0.03 g), GBL (6.00 g), BCS (4.00 g), a 10 mass % NMP solution of AD-1 (0.50 g), a 1 mass % NMP solution of AD-3 (1.00 g), and AD-5 (0.14 g) were added, and the mixture was stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent (B-5).

[0130] Comparative Example 6 Into a 30 mL Erlenmeyer flask containing a stirrer, the solution (1.83 g) of the polymer (polymer-3) obtained in Synthesis Example 3 and the solution (8.80 g) of the polymer (polymer-4) obtained in Synthesis Example 4 were weighed, and NMP (4.27 g), BCS (4.00 g) and a 1 mass % NMP solution (1.10 g) of AD-4 were added, followed by stirring at room temperature for 2 hours, thereby obtaining a liquid crystal aligning agent (B-6).

[0131] Comparative Example 7 The polyamic acid solution (polymer-10) (5.00 g) obtained in Synthesis Example 10 was weighed out, and NMP (5.00 g) and BCS (10.00 g) were added thereto, followed by stirring at room temperature for 2 hours to obtain a liquid crystal aligning agent (B-7).

[0132] Comparative Example 8 The polyamic acid solution (polymer-11) (5.00 g) obtained in Synthesis Example 11 was weighed out, and NMP (5.00 g) and BCS (10.00 g) were added thereto, followed by stirring at room temperature for 2 hours to obtain a liquid crystal aligning agent (B-8).

[0133] Example 31 To a 50 mL Erlenmeyer flask containing a stirrer, 3.30 g of the polyamic acid solution (polymer-1) obtained in Synthesis Example 1, 4.95 g of the polyamic acid solution (polymer-13) obtained in Synthesis Example 13, 0.33 g of a 3.0 mass % NMP solution of additive AD-3, 0.69 g of a 10 mass % NMP solution of AD-2, 3.15 g of NMP, 5.40 g of BCS, 0.079 g of additive AD-6, and 0.099 g of DL-menthol were added, and the mixture was stirred with a magnetic stirrer for 1 hour to obtain 5.5 mass % of a liquid crystal aligning agent (A-11).

[0134] Example 32 To a 50 mL Erlenmeyer flask containing a stirrer, 3.30 g of the polyamic acid solution (polymer-12) obtained in Synthesis Example 12, 4.95 g of the polyamic acid solution (polymer-13) obtained in Synthesis Example 13, 0.33 g of a 3.0 mass % NMP solution of additive AD-3, 0.69 g of a 10 mass % NMP solution of AD-2, 3.20 g of NMP, 5.40 g of BCS, 0.079 g of additive AD-6, and 0.050 g of DL-menthol were added, and the mixture was stirred with a magnetic stirrer for 1 hour to obtain a 5.5 mass % liquid crystal aligning agent (A-12).

[0135] Example 33 To a 50 mL Erlenmeyer flask containing a stirrer, 3.30 g of the polyamic acid solution (polymer-12) obtained in Synthesis Example 12, 4.95 g of the polyamic acid solution (polymer-13) obtained in Synthesis Example 13, 0.33 g of a 3.0 mass % NMP solution of additive AD-3, 0.69 g of a 10 mass % NMP solution of AD-2, 3.15 g of NMP, 5.40 g of BCS, 0.079 g of additive AD-6, and 0.099 g of DL-menthol were added, and the mixture was stirred with a magnetic stirrer for 1 hour to obtain 5.5 mass % of a liquid crystal aligning agent (A-13).

[0136] Example 34 To a 50 mL Erlenmeyer flask containing a stirrer, 3.10 g of the polyamic acid solution (polymer-12) obtained in Synthesis Example 12, 4.95 g of the polyamic acid solution (polymer-13) obtained in Synthesis Example 13, 0.33 g of a 3.0 mass % NMP solution of additive AD-3, 0.69 g of a 10 mass % NMP solution of AD-2, 3.15 g of NMP, 5.40 g of BCS, 0.079 g of additive AD-6, and 0.149 g of DL-menthol were added, and the mixture was stirred with a magnetic stirrer for 1 hour to obtain 5.5 mass % of a liquid crystal aligning agent (A-14).

[0137] Example 35 To a 50 mL Erlenmeyer flask containing a stirrer, 3.10 g of the polyamic acid solution (polymer-12) obtained in Synthesis Example 12, 4.95 g of the polyamic acid solution (polymer-13) obtained in Synthesis Example 13, 0.33 g of a 3.0 mass % NMP solution of additive AD-3, 0.69 g of a 10 mass % NMP solution of AD-2, 3.15 g of NMP, 5.40 g of BCS, 0.079 g of additive AD-6, and 0.099 g of DL-menthol were added, and the mixture was stirred with a magnetic stirrer for 1 hour to obtain 5.5 mass % of a liquid crystal aligning agent (A-15). Example 36 To a 50 mL Erlenmeyer flask containing a stirrer, 3.30 g of the polyamic acid solution (polymer-12) obtained in Synthesis Example 12, 4.95 g of the polyamic acid solution (polymer-13) obtained in Synthesis Example 13, 0.33 g of a 3.0 mass % NMP solution of additive AD-3, 0.69 g of a 10 mass % NMP solution of AD-2, 3.05 g of NMP, 5.40 g of BCS, 0.079 g of additive AD-6, and 0.198 g of D-menthol were added, and the mixture was stirred with a magnetic stirrer for 1 hour to obtain 5.5 mass % of a liquid crystal aligning agent (A-16). Example 37 To a 50 mL Erlenmeyer flask containing a stirrer, 3.30 g of the polyamic acid solution (polymer-12) obtained in Synthesis Example 12, 4.95 g of the polyamic acid solution (polymer-13) obtained in Synthesis Example 13, 0.33 g of a 3.0 mass % NMP solution of additive AD-3, 0.69 g of a 10 mass % NMP solution of AD-2, 3.05 g of NMP, 5.40 g of BCS, 0.079 g of additive AD-6, and 0.198 g of L-menthol were added, and the mixture was stirred with a magnetic stirrer for 1 hour to obtain 5.5 mass % of a liquid crystal aligning agent (A-17).

[0138] <Comparative Example 22> To a 50 mL Erlenmeyer flask containing a stirrer, 3.30 g of the polyamic acid solution (polymer-1) obtained in Synthesis Example 1, 4.95 g of the polyamic acid solution (polymer-13) obtained in Synthesis Example 13, 0.33 g of a 3.0 mass % NMP solution of additive AD-3, 0.69 g of a 10 mass % NMP solution of AD-2, 3.25 g of NMP, 5.40 g of BCS, and further 0.079 g of additive AD-6 were added, and the mixture was stirred with a magnetic stirrer for 1 hour to obtain 5.5 mass % of a liquid crystal aligning agent (B-9).

[0139] <Comparative Example 23> To a 50 mL Erlenmeyer flask containing a stirrer, 3.30 g of the polyamic acid solution (polymer-12) obtained in Synthesis Example 12, 4.95 g of the polyamic acid solution (polymer-13) obtained in Synthesis Example 13, 0.33 g of a 3.0 mass % NMP solution of additive AD-3, 0.69 g of a 10 mass % NMP solution of AD-2, 3.25 g of NMP, 5.40 g of BCS, and further 0.079 g of additive AD-6 were added, and the mixture was stirred with a magnetic stirrer for 1 hour to obtain 5.5 mass % of a liquid crystal aligning agent (B-10).

[0140] The polymers of the liquid crystal aligning agents obtained in Examples 1 to 10 and Comparative Examples 1 to 8, as well as Examples 31 to 37 and Comparative Examples 22 to 23, and the types and ratios of the component (C) (cyclic monoterpene compound component) described in the present invention are as shown in Tables 3 and 4 below. In the tables, the parenthesized numbers for the component (C) (cyclic monoterpene compound component) described in the present invention represent the content (% by mass) of each compound relative to 100% by mass of the total amount of each liquid crystal aligning agent. Furthermore, the polymer concentration represents the content (% by mass) of the first polymer component and / or the second polymer component relative to 100% by mass of the total amount of each liquid crystal aligning agent. The parenthesized numbers for the first polymer or second polymer in Examples 31 to 37 and Comparative Examples 22 to 23 represent the content (parts by mass) of the first polymer component or the second polymer component relative to 100 parts by mass of the total amount of the polymer contained in each liquid crystal aligning agent.

[0141]

[0142]

[0143] [Printability evaluation and film thickness measurement] (Examples 11 to 20 and Comparative Examples 9 to 16) The liquid crystal alignment agents (A-1) to (A-10) and (B-1) to (B-8) obtained in Examples 1 to 10 and Comparative Examples 1 to 8 were each filtered through a filter with a pore size of 1.0 μm, and then flexographically printed on a cleaned Cr-deposited substrate using an alignment film printer ("Angstromer" manufactured by Nissha Printing Co., Ltd.), thereby conducting a printability test. The specifications of the anilox roll and printing plate are as follows: Anilox roll: Material: Ceramic Line count: 400 lines / inch, Depth: 20 μm Printing plate: Material: APR resin Line count: 600 lines / inch, Angle: 52°, Opening rate: 20%

[0144] Specifically, the procedure was as follows. Approximately 1.0 mL of liquid crystal alignment agent was dropped onto an anilox roll, and after five idle runs, printing was performed on one Cr-vapor-deposited substrate (100 mm length × 100 mm width, 1.0 mm thickness) under the conditions of a print setting of 80 mm × 80 mm and a printing pressure of 0.2 mm. After printing, the substrate was left on a hot plate at 80°C for 90 seconds to pre-dry the coating film, and the film condition was visually observed. The presence or absence of film thickness unevenness and pinholes was checked, and a "Good" was given if there were no film thickness unevenness or pinholes, and a "Poor" was given if there were any film thickness unevenness or pinholes. Furthermore, the substrate with the liquid crystal alignment film was baked in a hot air circulation oven at 230°C for 30 minutes, and the film thickness of the resulting liquid crystal alignment film was measured using a small microscopic shape measuring instrument (ET-200, manufactured by Kosaka Laboratory Co., Ltd.). The evaluation results for printability and film thickness are shown in Table 5 below.

[0145]

[0146] Comparing the results of Examples 11 to 20 and Comparative Examples 9 and 11 to 16, it was confirmed that the liquid crystal alignment film obtained from the liquid crystal aligning agent containing the component (C) has a thicker film thickness than the liquid crystal alignment film obtained from the liquid crystal aligning agent not containing the component (C). Furthermore, from the results of Examples 11 to 13 and Comparative Example 10, it was confirmed that even when the concentration of the polymer contained in the liquid crystal aligning agent is low, the liquid crystal alignment film obtained from the liquid crystal aligning agent containing the component (C) has good printability and is thick.

[0147] [Fabrication of FFS Drive Liquid Crystal Cells (Photo-Alignment Treatment)] (Examples 21-27 and Comparative Examples 17-20) Liquid crystal cells (hereinafter also referred to as FFS liquid crystal cells) having the configuration of an FFS drive liquid crystal display element were fabricated. First, a substrate with electrodes was prepared. The substrate was a 30 mm x 50 mm glass substrate with a thickness of 0.7 mm. A solid-patterned ITO electrode constituting a counter electrode was formed on the substrate as the first layer. A SiN (silicon nitride) film formed by CVD was formed as the second layer on the first counter electrode. The second SiN film had a thickness of 500 nm and functioned as an interlayer insulating film. A comb-shaped pixel electrode formed by patterning an ITO film was disposed on the second SiN film as the third layer, forming two pixels, a first pixel and a second pixel. Each pixel measured 10 mm long and approximately 5 mm wide. At this time, the first layer of counter electrodes and the third layer of pixel electrodes were electrically insulated by the action of the second layer of SiN film.

[0148] The pixel electrodes in the third layer had a comb-like shape, with multiple 3 μm-wide electrode elements bent at a 160° interior angle at the center and arranged parallel to each other at 6 μm intervals. Each pixel had a first region and a second region, separated by a line connecting the bent portions of the multiple electrode elements. The first and second regions of each pixel were found to have different orientations of the electrode elements of the pixel electrodes. That is, based on the orientation connecting the bent portions of the multiple electrode elements, the electrode elements of the pixel electrode in the first region of the pixel were formed at an 80° clockwise angle, while the electrode elements of the pixel electrode in the second region of the pixel were formed at an 80° counterclockwise angle. In other words, the first and second regions of each pixel were configured such that the in-plane switching (in-plane switching) directions of the liquid crystal molecules induced by the application of a voltage between the pixel electrode and the counter electrode were opposite to each other.

[0149] Next, the liquid crystal alignment agents (A-1) to (A-7) obtained in Examples 1 to 7 and the liquid crystal alignment agents (B-1) and (B-3) to (B-4) obtained in Comparative Examples 1, 3, and 4 were filtered through a 1.0 μm filter and then spin-coated onto the electrode-attached substrate and a glass substrate having 4 μm-high columnar spacers and an ITO film formed on the backside. After drying for 5 minutes on a hot plate at 80°C, the substrate was baked for 30 minutes in a hot air circulating oven at 230°C to form a coating film with a thickness of 100 nm. Next, a photoalignment treatment was performed. Specifically, the coating surface was irradiated with linearly polarized ultraviolet light with a wavelength of 254 nm and an extinction ratio of 10:1 or greater through a polarizer. The UV dose was determined under the conditions listed in Table 6 below. Next, the substrate with the coating was heated on a hot plate at 230°C for 30 minutes to obtain a substrate with a liquid crystal alignment film.

[0150]

[0151] Two substrates with the above liquid crystal alignment film were prepared, and a sealant (Mitsui Chemicals, Inc., XN-1500T) was printed around the periphery, leaving the liquid crystal injection port. The substrates were then bonded together so that the liquid crystal alignment film surfaces faced each other and the alignment direction was 0°. This was then heated at 120°C for 90 minutes to harden the sealant, producing an empty cell. Positive liquid crystal MLC-3019 (Merck & Co., Inc.) was vacuum injected into this empty cell at room temperature, and the injection port was then sealed to produce an anti-parallel aligned FFS liquid crystal cell. The resulting FFS liquid crystal cell was heated at 120°C for 1 hour, left overnight at 23°C, and then used for the following evaluations.

[0152] [Fabrication of FFS Liquid Crystal Cell (Rubbing Alignment Treatment)] (Example 28 and Comparative Example 21) A substrate with electrodes similar to those described above and a glass substrate with columnar spacers were prepared. Then, a coating film with a thickness of 100 nm was formed in the same manner as in Examples 21 to 27 and Comparative Examples 17 to 20, except that the liquid crystal alignment agent (A-8) obtained in Example 8 and the liquid crystal alignment agent (B-6) obtained in Comparative Example 6 were used. Next, the alignment treatment was performed by changing the photoalignment treatment to the rubbing alignment treatment described below. Specifically, the substrate on which the coating film had been formed was rubbed with a rayon cloth (roller diameter: 140 mm, roller rotation speed: 1000 rpm, movement speed: 30 mm / sec, indentation length: 0.3 mm). The substrate was then washed by ultrasonic irradiation in pure water for 1 minute, water droplets were removed by air blowing, and then dried at 80°C for 10 minutes to obtain a substrate with a liquid crystal alignment film. Two substrates with the liquid crystal alignment film thus obtained were prepared, and FFS liquid crystal cells were fabricated in the same manner as above, and used for the following evaluations.

[0153]

[0154] [Evaluation of Long-Term Image Retention at Room Temperature] The FFS liquid crystal cell prepared above was placed in a crossed Nicol state using two polarizing plates, and the luminance was 10,000 cd / m 2 While irradiating the display with an LED backlight, an AC voltage of ±6.2 V at a frequency of 30 Hz was applied to the first pixel for 24 hours. Thereafter, an AC voltage of ±2.9 V at a frequency of 30 Hz was applied to each of the first pixel and the second pixel. The luminance (A) of the first pixel and the luminance (B) of the second pixel immediately after switching the drive voltage were measured using a luminance and chromaticity uniformity meter (manufactured by TOPCON Corporation, model: UA-10H). The rate of change in the luminance (A) of the first pixel relative to the luminance (B) of the second pixel was calculated using the following formula: Luminance change rate [%] = (A - B) / B × 100. It can be said that the smaller the luminance change rate value, the better the afterimage characteristics.

[0155] [Evaluation of Flicker Characteristics] The FFS liquid crystal cell prepared above was placed in a crossed Nicol state using two polarizing plates, and the luminance was 10,000 cd / m 2While irradiating the first pixel with an LED backlight, an AC voltage of ±2.9 V at a frequency of 30 Hz was applied to the first pixel. The flicker at this time was measured using a display color analyzer (Konica Minolta, model: CA-410), and while the AC voltage was applied, a DC voltage was applied so that the flicker value was minimized. Thereafter, the AC and DC voltages were applied for 30 minutes, and the flicker after 30 minutes of driving was measured again. The unit of flicker was dB (decibels). It can be said that the smaller the value (the more negative the value), the better the flicker characteristics.

[0156] The results of the room temperature long-term image retention evaluation and flicker characteristic evaluation are shown in Table 8 below.

[0157]

[0158] [Preparation of Vertically Aligned Liquid Crystal Cell] (Examples 29-30) Liquid crystal cells were prepared using the liquid crystal alignment agents (A-9) to (A-10) obtained in Examples 9 to 10 of the liquid crystal alignment agent described above, according to the procedure described below. Each liquid crystal alignment agent was spin-coated onto a glass substrate (3 cm wide x 4 cm long) with an ITO electrode, dried on a hot plate at 70°C for 90 seconds, and then baked in an infrared heating furnace at 230°C for 20 minutes to prepare a glass substrate (substrate with liquid crystal alignment film) on which a 100 nm-thick liquid crystal alignment film was formed. Two of these liquid crystal alignment film-formed substrates were prepared, and 4 μm diameter bead spacers (SW-D1, manufactured by JGC Catalysts and Chemicals Co., Ltd.) were applied to the surface on which the liquid crystal alignment film was formed of one of the liquid crystal alignment film-formed substrates, and a thermosetting sealant (XN-1500T, manufactured by Mitsui Chemicals, Inc.) was printed around the periphery, leaving only the liquid crystal injection port. Next, the other substrate with a liquid crystal alignment film was bonded to the previous substrate with the side on which the liquid crystal alignment film was formed facing inward, and then heat-treated at 150°C for 60 minutes to harden the sealant and prepare an empty cell. Negative liquid crystal MLC-3023 (manufactured by Merck) was injected into this empty cell by a reduced pressure injection method to prepare a liquid crystal cell. Next, with a DC voltage of 15 V applied to this liquid crystal cell, ultraviolet light was irradiated from the outside of the liquid crystal cell at 10 J / cm through a cut filter for wavelengths of 325 nm or less. ２The illuminance of the ultraviolet light was measured using an illuminance meter with an ultraviolet actinometer (UV-M03A, manufactured by ORC Corporation). Thereafter, in order to deactivate any unreacted polymerizable compound remaining in the liquid crystal cell, the liquid crystal cell was irradiated with UV (UV lamp: FLR40SUV32 / A-1) for 30 minutes using an irradiation unit (UV-FL irradiation device, manufactured by Toshiba Lighting & Technology Corporation) in the absence of applied voltage (hereinafter, also referred to as PSA treatment).

[0159] [Evaluation of Liquid Crystal Alignment] The liquid crystal cells prepared in Examples 29 and 30 above were observed with a polarizing microscope (Nikon Corporation's "ECLIPSE E600WPOL") to confirm the alignment state of the liquid crystal. As an evaluation criterion, a case where no bright spots due to defects caused by liquid crystal flow or alignment defects were observed was marked as "○", and a case where bright spots due to defects caused by liquid crystal flow or alignment defects were observed was marked as "×". The evaluation results are shown in Table 9.

[0160]

[0161] Comparing the results of Examples 21 to 28 and Comparative Examples 17 to 21, it was confirmed that the FFS liquid crystal cells using the liquid crystal alignment film obtained from the liquid crystal aligning agent containing the component (C) have better long-term image retention characteristics and flicker characteristics at room temperature than the FFS liquid crystal cells using the liquid crystal alignment film obtained from the liquid crystal aligning agent not containing the component (C). In other words, it was confirmed that the liquid crystal display element using the liquid crystal aligning agent of the present invention has excellent image retention characteristics and excellent flicker characteristics.

[0162] [Fabrication of FFS Drive System Liquid Crystal Cells (Photo-Alignment Treatment)] (Examples 38 to 42 and Comparative Examples 24 to 25) Using the liquid crystal alignment agents (A-11) to (A-15) obtained in Examples 31 to 35 and the liquid crystal alignment agents (B-9) to (B-10) obtained in Comparative Examples 22 and 23, the irradiation dose of ultraviolet light with a wavelength of 254 nm during the photo-alignment treatment was 400 mJ / cm. ２ Except for the above, FFS liquid crystal cells were obtained in the same manner as in Examples 21 to 27 and Comparative Examples 17 to 20. The obtained FFS liquid crystal cells were heated at 120°C for 1 hour, left to stand at 23°C overnight, and then used for the following evaluations.

[0163] [Evaluation of In-Plane Uniformity] The variation in the twist angle of the liquid crystal cell was evaluated using an AxoStep manufactured by AXOMETRICS. The liquid crystal cells produced in Examples 38 to 42 and Comparative Examples 24 and 25 above were placed on a measurement stage, and the distribution of circular retardance within the pixel plane was measured with no voltage applied, and 3σ, which is three times the standard deviation σ, was calculated. The smaller the 3σ value, the better the in-plane uniformity.

[0164] [Preparation of Adhesion Evaluation Samples] (Examples 43-47 and Comparative Examples 26-27) The liquid crystal alignment agents (A-11) to (A-15) obtained in Examples 31-35 and the liquid crystal alignment agents (B-9) to (B-10) obtained in Comparative Examples 22-23 were filtered through a 1.0 μm pore size filter, spin-coated onto a glass substrate equipped with a transparent electrode, dried on a hot plate at 80°C for 2 minutes, and then baked at 230°C for 20 minutes to obtain a coating film with a thickness of 70 nm. Two substrates were prepared in this manner, and 4 μm diameter bead spacers (manufactured by JGC Catalysts and Chemicals, Shinshikyu, SW-D1) were sprayed onto the liquid crystal alignment film surface of one substrate, followed by the addition of a drop of UV (ultraviolet) curable adhesive. Next, the liquid crystal alignment film surface of the other substrate was placed inside, and the substrates were bonded together so that the overlap width was 0.5 cm. The amount of sealing agent dispensed was adjusted so that the diameter of the sealing agent after bonding would be approximately 3 mm. After the two bonded substrates were fixed with clips, UV rays with a wavelength of 365 nm were applied at 3.0 J / cm using a cut filter for wavelengths of 325 nm or less. ２ After irradiation, the coating was heat cured at 120°C for 1 hour to prepare a sample for evaluating adhesiveness.

[0165] [Measurement of Adhesion Strength] The samples prepared in Examples 43 to 47 and Comparative Examples 26 to 27 above were fixed at the edges of the upper and lower substrates using a bench-top precision universal testing machine, and then pulled up and down from both ends of the short sides of the substrates to measure the pressure (N) applied when peeling. The adhesive strength was then evaluated using a value obtained by normalizing the pressure (N) by the area (mm2) estimated from the diameter of the measured sealant. The higher the adhesion strength, the better the result.

[0166] [Evaluation of Long-Term Image Retention at Room Temperature] A long-term image retention evaluation at room temperature was carried out using the FFS liquid crystal cells prepared in Examples 38 to 42 and Comparative Examples 24 and 25. The measurement results of the in-plane uniformity evaluation, seal adhesion, and long-term image retention evaluation at room temperature are shown in Table 10 below.

[0167]

[0168] From the comparison between the Examples and Comparative Examples in Table 10, it was confirmed that by adding a small amount of DL-menthol, D-menthol, or L-menthol to the liquid crystal alignment agent, the adhesion strength of the liquid crystal alignment film can be increased while maintaining good alignment uniformity and long-term image retention properties at room temperature.

[0169] The present invention is not limited to the above-described embodiment, and various modifications and improvements can be made to the above-described embodiment. Modifications are described below.

[0170] In the above embodiment, the liquid crystal aligning agent using limonene has been described, but other terpene hydrocarbons, terpene alcohols, or derivatives thereof can be used instead of limonene. Furthermore, solvents other than NMP and BCS can also be used as solvents other than limonene. The following are examples of preferred solvent compositions for the liquid crystal aligning agent. a combination of pinene (α-pinene, β-pinene) with NMP and BCS; a combination of terpinene (α-terpinene, β-terpinene, γ-terpinene) with NMP and BCS; a combination of menthol with NMP and BCS; a combination of limonene (D-, L-, or DL-form) with N-ethyl-2-pyrrolidone and butyl cellosolve; a combination of limonene (D-, L-, or DL-form) with 3-methoxy-N,N-dimethylpropanamide and butyl cellosolve; a combination of limonene (D-, L-, or DL-form) with NMP and diisobutyl ketone; a combination of limonene (D-, L-, or DL-form) with NMP and diacetone alcohol; a combination of limonene (D-, L-, or DL-form) with NMP and diethylene glycol diethyl ether;

[0171] By using a liquid crystal alignment film having the configuration of the present invention, it is possible to suppress the elution of impurities from the electrode substrate and color filter substrate into the liquid crystal layer, thereby providing a liquid crystal display element with excellent image retention and reliability. Furthermore, by using a liquid crystal display element having the configuration of the present invention, it is possible to obtain a liquid crystal display element with excellent image retention and flicker characteristics that occur immediately after switching when the display brightness is significantly changed. Therefore, it is expected to be used in liquid crystal display elements that require high display quality. Furthermore, these elements are useful in liquid crystal displays for display purposes, as well as in light control windows and optical shutters that control the transmission and blocking of light.

Claims

1. A liquid crystal alignment agent containing a polymer component (P) and a component (C) that contains one or more polymers, A liquid crystal alignment agent wherein the polymer component (P) contains at least one polymer (P) selected from the group consisting of polyimide precursors and polyimides which are imidized products of the polyimide precursor. (C) Component: One or more compounds selected from the group consisting of cyclic monoterpene compounds (compound (C)).

2. The liquid crystal alignment agent according to claim 1, wherein the compound (C) is a solvent having a boiling point of less than 260°C at normal pressure.

3. The liquid crystal alignment agent according to claim 1, wherein the compound (C) is selected from terpene hydrocarbons, terpene alcohols, or terpene ketones.

4. The liquid crystal aligning agent according to claim 1, wherein the compound (C) is selected from limonene, pinene, camphene, phellandrene, terpinene, terpinolene, or 3-carene, isopulegol, menthol, terpineol, carveol, dihydrocarveol, perilla alcohol (periryl alcohol), 4-thujanol, isocyclogeraniol, α-fenquil alcohol (fencol), borneol, or isoborneol, and camphor.

5. The liquid crystal alignment agent according to claim 1, wherein the polymer (P) has one or more structural units, and has at least one structural unit selected from the group consisting of a structural unit (p0) represented by the following formula (P0) and an imidized structural unit of the structural unit (p0). 【Chemistry 1】 (In formula (P0), X represents a tetravalent organic group, and Y represents a divalent organic group. R and Z each independently represent a hydrogen atom or a monovalent organic group. Multiple R and Z elements each independently have the above definitions.)

6. The liquid crystal alignment agent according to claim 5, wherein the divalent organic group of Y in formula (P0) is a divalent organic group represented by the following formulas (3) to (4). 【Chemistry 2】 (In equations (3) and (4), R ３ , R ４ , and R ４’ Each of these independently represents a halogen atom, a hydroxyl group, an optionally protected amino group, a thiol group, a nitro group, a phosphate group, or a monovalent organic group having 1 to 20 carbon atoms. A ４ R represents an ester bond, amide bond, thioester bond, or a divalent organic group having 2 to 20 carbon atoms. However, in the case of a 1,4-phenylene group, 1 to 4 hydrogen atoms on the phenylene group are R. ４ , and R ４’ Excluding divalent organic groups that are substituted with or divalent organic groups formed by linking these divalent organic groups together. a3, a4, and a4' are each independent integers between 0 and 4. a is an integer from 1 to 4. b and c are each independently an integer from 1 to 2. R ３ , R ４ , R ４’ , when there are a plurality of R ３ , R ４ , and R ４’ may have the same or different structures. When there are a plurality of a3, a4, and a4', they may be the same or different from each other. * represents a bond.)

7. The liquid crystal alignment agent according to claim 1, wherein the polymer (P) is a polymer comprising a structural unit having a divalent organic group selected from the group consisting of a divalent organic group having a urea bond, a divalent organic group having an amide bond, a nitrogen atom-containing heterocycle, a secondary amino group, and a tertiary amino group, and a divalent organic group having a carboxyl group.

8. The liquid crystal alignment agent according to claim 1, wherein the polymer constituting the polymer component (P) does not have an acid-leaving group.

9. A liquid crystal alignment agent containing a polymer component (P) and a component (C) that contains two or more polymers, A liquid crystal alignment agent wherein the polymer component (P) satisfies at least one of the following conditions (i) to (iii), and the component (C) is a cyclic monoterpene compound. (i) A polymer component (P1) comprising at least two polymers selected from the group consisting of a polyimide precursor (A) having one or more structural units and a structural unit (a1) represented by the following formula (A1), and a polyimide which is an imidized product of the polyimide precursor. (ii) A polymer different from the polyimide precursor (A), comprising two or more polyimide precursors (B) having one or more structural units, and each having a structural unit (b1) represented by the following formula (B1). (iii) Polymer component (P3) comprising the polyimide precursor (A) and polyimide which is an imidized product of the polyimide precursor, and the polyimide precursor (B). 【Transformation 3】 (In equation (A1), X ａ１ This represents a tetravalent organic group selected from the group consisting of the following formulas (Xa1-1) to (Xa1-8), Y ａ１ (The letter R represents a divalent organic group. Multiple R's and Z's each independently represent a hydrogen atom or a monovalent organic group.) 【Chemistry 4】 (In equations (Xa1-1) to (Xa1-3), R １ From R １５ Each of these independently represents a hydrogen atom, a halogen atom, a C1-C6 alkyl group, a C2-C6 alkenyl group, a C2-C6 alkynyl group, a C1-C6 monovalent organic group containing a fluorine atom, or a phenyl group, and may be the same or different. * represents a bond. 【Transformation 5】 (In equation (B1), X ｂ１ X represents a tetravalent organic group having an aromatic group with 6 to 30 carbon atoms, ｂ１ At least one of the carbonyl carbons bonded to it is X ｂ１ It bonds with the aromatic group of Y. ｂ１ R represents a divalent organic group. R and Z each independently represent a hydrogen atom or a monovalent organic group. Multiple R and Z groups each independently have the above definitions.

10. A liquid crystal alignment film obtained from a liquid crystal alignment agent according to any one of claims 1 to 7 or 9.

11. A method for manufacturing a liquid crystal alignment film, comprising the following steps (1) to (3). Step (1): A step of applying the liquid crystal alignment agent according to any one of claims 1 to 7, 9 onto a substrate. Step (2): A step of firing the applied liquid crystal alignment agent. Step (3): A step of orientation treatment on the film obtained in step (2).

12. The method for manufacturing a liquid crystal alignment film according to claim 11, wherein the alignment treatment is a photo-alignment treatment.

13. A method for manufacturing a liquid crystal alignment film according to claim 11, further comprising the following firing step after step (3). Firing process: A process of firing at 150°C to 300°C.

14. A liquid crystal alignment film formed by the method for manufacturing a liquid crystal alignment film according to claim 11.

15. A liquid crystal display element comprising the liquid crystal alignment film described in claim 10.

16. A liquid crystal display element comprising the liquid crystal alignment film described in claim 14.

17. A method for manufacturing a liquid crystal display element, comprising forming a liquid crystal alignment film as described in claim 10.

18. A method for manufacturing a liquid crystal display element, comprising forming a liquid crystal alignment film as described in claim 14.

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