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

Abstract

A liquid crystal alignment agent is provided, which can suppress silver migration when silver-containing materials are used as electrodes and wiring of a liquid crystal display element, and maintain a high voltage retention rate even after prolonged exposure to high temperatures. The liquid crystal alignment agent also provides a liquid crystal alignment film obtained from the liquid crystal alignment agent and a liquid crystal display element using the liquid crystal alignment film. The liquid crystal alignment agent comprises the following component (A) and a compound (B) represented by the following formula (1). Component (A): A polymer (A) selected from the group consisting of a polyimide precursor obtained by polymerizing a tetracarboxylic acid derivative component with a diamine component, and a polyimide as a polyimide precursor amide. The tetracarboxylic acid derivative component comprises at least one compound selected from the group consisting of tetracarboxylic acid dianhydrides and their derivatives. The amount of carboxyl groups bonded to the aromatic ring is 5 parts by mass or less per 100 parts by mass of the polymer. (A1 represents a monovalent group or hydrogen atom having a trialkoxysilyl group, and A2 independently represents an alkyl group, carboxyl group or hydrogen atom having 1 to 4 carbon atoms respectively).

Description

[Technical Field]

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

[0002] As liquid crystal display components, various driving modes have been developed for different electrode configuration, physical properties of liquid crystal molecules used, manufacturing steps, etc. It is known that there are, for example, TN (twisted nematic) type, STN (super-twisted nematic) type, VA (vertical alignment) type, MVA (multi-domain vertical alignment) type, IPS (in-plane switching) type, IPS (in-plane switching) type (polymer-sustained alignment) type and other liquid crystal display components. Such liquid crystal display elements have a liquid crystal alignment film used to align the liquid crystal molecules. The materials of liquid crystal aligned films, in terms of various characteristics such as heat resistance, mechanical strength, affinity with liquid crystals, etc. are good, are generally the use of sheets composed of polymers containing polyamide, polyimide, polysiloxane, etc.

[0003] With the high refinement of liquid crystal display components, the requirements of suppressing the contrast reduction of liquid crystal display components or reducing the afterimage phenomenon, for liquid crystal alignment films, in addition to exhibiting excellent liquid crystal alignment or stable pre-tilt angle, high voltage retention rate, suppression of afterimages due to AC drive, less residual charge when applying DC voltage, and / or faster easing of residual charges that gradually become important due to DC voltage. Various proposals have been made in liquid crystal alignment films of polyamide systems in order to correspond to the requirements as described above (reference patents 1~5).

[0004] On the other hand, electrodes and wiring as liquid crystal display components are known to produce a variety of problems if specific metal materials are used. For example, one literature (reference Patent 6) is known to have improved the problem when using electrodes and wiring containing copper or aluminum by using a liquid crystal alignment film that introduces a side chain containing a benzotriazole group. However, other solutions must be requested for the configuration characteristic of the side chain introduction of the polymer and thus the lower design freedom as a liquid crystal alignment film.

[0005] Furthermore, regarding the same problem, one document (see Patent Document 7) is known to improve the problem by adding a component containing benzotriazole to the liquid crystal. However, since the additives used in the liquid crystal vary depending on the type of liquid crystal, there is a possibility that they may have an adverse effect on the alignment of the liquid crystal. [Prior Art Documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Unexamined Patent Publication No. 9-316200 [Patent Document 2] Japanese Unexamined Patent Publication No. 10-104633 [Patent Document 3] Japanese Unexamined Patent Publication No. 8-76128 [Patent Document 4] Japanese Unexamined Patent Publication No. 9-138414 [Patent Document 5] Japanese Unexamined Patent Publication No. 11-38415 [Patent Document 6] WO2016 / 194667 [Patent Document 7] WO2016 / 194668 [Summary of the Invention]

[0007] [The problem the invention aims to solve]

[0008] When materials containing silver are used as electrodes and wiring in liquid crystal display elements, conventional liquid crystal alignment agents can cause silver migration, which becomes a problem. To address this, aluminum or nickel can be used as alternatives to silver, thus improving the migration. However, there are issues such as reduced reflectivity when aluminum or nickel is used as electrodes, and reduced conductivity when used as wiring, thus there is room for improvement.

[0009] This invention was made in view of the above-mentioned circumstances, and its object is to provide a liquid crystal alignment agent that can suppress silver migration and the migration of silver-containing electrodes or wirings used as electrodes and wirings in a liquid crystal display element, and maintain a high voltage retention rate even after prolonged exposure to high temperatures; and to provide a liquid crystal alignment film obtained from the liquid crystal alignment agent and a liquid crystal display element using the liquid crystal alignment film. [Means for Solving the Problem]

[0010] In order to achieve the above-mentioned objectives, the inventors have repeatedly and thoroughly studied and discovered that liquid crystal alignment agents contain polymers with specific compounds as constituent components, which are extremely effective in achieving the above-mentioned objectives, and thus the present invention has been completed.

[0011] The present invention includes the following. A liquid crystal alignment agent comprising the following component (A) and a compound (B) represented by the following formula (1), wherein the component (A) is a polymer (A) selected from the group consisting of a polyimide precursor obtained by polymerizing a tetracarboxylic acid derivative component and a diamine component, and a polyimide as a polyimide precursor, the tetracarboxylic acid derivative component comprising at least one compound selected from the group consisting of tetracarboxylic acid dianhydrides and their derivatives, and the content of a carboxyl group bonded to an aromatic ring is 5 parts by mass or less relative to 100 parts by mass of the polymer; (A1 represents a monovalent group having a trialkoxysilyl group or a hydrogen atom, and A2 independently represents an alkyl group, a carboxyl group or a hydrogen atom having 1 to 4 carbon atoms respectively).

[0012] [Effects of the Invention] The present invention provides a liquid crystal alignment agent that can suppress silver migration when the electrodes and wiring of a liquid crystal display element are made of a material containing silver, and maintain a high voltage retention rate even after prolonged exposure to high temperatures. The present invention also provides a liquid crystal alignment film obtained from the liquid crystal alignment agent and a liquid crystal display element using the liquid crystal alignment film.

[0013] It is generally known that by placing a benzotriazole derivative onto the surface of a silver-containing electrode or wiring, a coating is formed on the silver surface, thereby suppressing the degradation of the electrode or wiring. However, the inventors have discovered through research that, depending on the properties of the polymer in contact with the silver-containing electrode or wiring, the aforementioned coating may be damaged, leading to the degradation of the electrode or wiring. In response, the inventors have found that by combining a polymer (A) containing only a specific mass fraction or less of carboxyl groups bonded to an aromatic ring, and a compound (B), both the properties of suppressing the migration of silver-containing electrodes or wiring and the properties of serving as a liquid crystal alignment film can be achieved.

Implementation Method

[0015] [Optimal Form for Implementing the Invention]

[0016] Hereinafter, a liquid crystal alignment agent containing specific components, a liquid crystal alignment film formed using the liquid crystal alignment agent, and a liquid crystal display element having the liquid crystal alignment film will be described in detail. However, the description of the constituent elements described below is only one example of one embodiment of the present invention and is not specific to those contents. In the following description, examples of "halogen atoms" include fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc. "Boc" represents tert-butoxycarbonyl, and "*" indicates the bond position.

[0017] <Polymer (A)> The liquid crystal alignment agent of the present invention includes the above-mentioned component (A). Furthermore, the term "polymer component" means a component composed of polymers, which may be composed of one type of polymer or multiple types of polymers. Also, polymer (A) may be one type or two or more types. The polymer (A) contained in the above-mentioned component (A) is selected from the group consisting of a polyimide precursor obtained by polymerizing a tetracarboxylic acid derivative component with a diamine component, and a polyimide as a polyimide derivative of the polyimide precursor. The tetracarboxylic acid derivative component includes at least one compound selected from the group consisting of tetracarboxylic dianhydrides and their derivatives (hereinafter, the polymer (A) is also referred to as "polyimide-based polymer (A)"). The polyimide precursor in the polyimide-based polymer (A) is obtained by polymerizing a tetracarboxylic acid derivative component with a diamine component. The tetracarboxylic acid derivative component comprises at least one compound selected from the group consisting of tetracarboxylic dianhydrides and their derivatives (hereinafter, these are also collectively referred to as "tetracarboxylic dianhydride compounds"). Examples of polyimide precursors include polyamide and polyamide esters. Examples of tetracarboxylic dianhydride derivatives include tetracarboxylic acid dihalides, tetracarboxylic acid dialkyl esters, or tetracarboxylic acid dialkyl ester dihalides.

[0018] <<Polyimine-based polymer (A)>> If the above-mentioned polyimine-based polymer (A) is a polyamide, for example, it can be obtained by polymerizing (polycondensing) a tetracarboxylic acid derivative component containing a tetracarboxylic acid dianhydride with a diamine component. Alternatively, the polyimide in the above-mentioned polyimine-based polymer (A) can be obtained by amide-imidizing the polyamide. Furthermore, if the above-mentioned polyimine-based polymer (A) is a polyamide ester, it can be obtained by the method described later, by amide-imidizing the polyamide ester to obtain the polyimide.

[0019] <<<Tetracarboxylic dianhydride compounds>>> Examples of the above-mentioned tetracarboxylic dianhydride compounds include: aromatic tetracarboxylic dianhydrides, acyclic aliphatic tetracarboxylic dianhydrides, or alicyclic tetracarboxylic dianhydrides, or derivatives thereof. Here, aromatic tetracarboxylic dianhydrides are acid dianhydrides obtained by the following operation: by intramolecularly dehydrating four carboxyl groups, including at least one carboxyl group bonded to an aromatic ring. Acyclic aliphatic tetracarboxylic dianhydrides are acid dianhydrides obtained by the following operation: by intramolecularly dehydrating four carboxyl groups bonded to a chain hydrocarbon structure. However, it is not necessary to have only a chain hydrocarbon structure; this part may also have an alicyclic or aromatic ring structure.

[0020] Furthermore, the alicyclic tetracarboxylic dianhydride is an acid dianhydride obtained by the following operation: by intramolecular dehydration of four carboxyl groups, including at least one carboxyl group bonded to the alicyclic structure. However, none of these four carboxyl groups are bonded to an aromatic ring. Also, it is not necessary to have only an alicyclic structure; this portion may also have a chain hydrocarbon structure or an aromatic ring structure.

[0021] Of the above-mentioned aromatic tetracarboxylic dianhydrides, acyclic aliphatic tetracarboxylic dianhydrides or alicyclic tetracarboxylic dianhydrides, the tetracarboxylic dianhydride represented by the following formula (2) is preferred.

[0022] (X represents the construction of the group selected from the following formulas (x-1)~(x-17) and (xr-1)~(xr-2).

[0023]

[0024] (R1~R4 independently represent hydrogen atom, halogen atom, alkyl group with 1~6 carbon atoms, alkenyl group with 2~6 carbon atoms, alkynyl group with 2~6 carbon atoms, monovalent organic group with 1~6 carbon atoms containing fluorine atom, alkoxy group with 1~6 carbon atoms, alkoxyalkyl group with 2~6 carbon atoms, alkyloxycarbonyl group with 2~6 carbon atoms, or phenyl group; R5 and R6 independently represent hydrogen atom or methyl group; j and k are integers 0 or 1; A1 and A2 independently represent single bond, -O-, -CO-, -COO-, phenyl, sulfonyl, or amino group, and multiple A2 can be the same or different; *1 is a bond bonded to one anhydride group; *2 is a bond bonded to the other anhydride group).

[0025] As a preferred specific example of the tetracarboxylic acid dianhydride represented by the above formula (2), X can be selected from the tetracarboxylic acid dianhydrides of the above formulas (x-1)~(x-8) and (x-10)~(x-11).

[0026] Of the above formula (x-1), it is preferable to select the group composed of the following formulas (x1-1) to (x1-6). X is preferably selected from the group composed of the following formulas (x1-1) to (x1-6), the above formulas (x-5), (x-6) and (x-7).

[0027] (*1 is a bond bonded to one anhydride group; *2 is a bond bonded to the other anhydride group).

[0028] As a preferred specific example of the above formulas (xr-1) and (xr-2), the following formulas (xr-3) to (xr-18) can be given.

[0029]

[0030]

[0031] When manufacturing polyimide polymer (A), the amount of tetracarboxylic acid dianhydride or its derivative represented by the above formula (2) is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 20 mol% or more, relative to 1 mol of the tetracarboxylic acid derivative component that reacts with the diamine component.

[0032] <<<Diamine Component>>> The diamine component used in the manufacture of polyimide precursors is not particularly limited. Examples of diamines are given below, but the present invention is not limited to these. The aforementioned diamines may be used alone or in combination of two or more.

[0033] p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, m-phenylenediamine, 2,4-dimethyl-m-phenylenediamine, 1,4-diamino-2,5-dimethoxybenzyl, 2,5-diaminotoluene, 2,6-diaminotoluene, 4-aminobenzylamine, 2-(4-aminophenyl)ethylamine, 4-(2-(methylamino)ethyl)aniline, 4-(2-aminoethyl)aniline, 2-(6-amino-2-naphthyl)ethylamine, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl -Diaminobiphenyl, 3-trifluoromethyl-4,4'-diaminobiphenyl, 2-trifluoromethyl-4,4'-diaminobiphenyl, 3-fluoro-4,4'-diaminobiphenyl, 2-fluoro-4,4'-diaminobiphenyl, 2,2'-difluoro-4,4'-diaminobiphenyl, 3,3'-difluoro-4,4'-diaminobiphenyl, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,3'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 4,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,2'-diaminobiphenyl, 2,3'-diaminobiphenyl, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 2,5-diaminobiphenyl Aminonaphthalene, 2,6-diaminonaphthalene, 2,7-diaminonaphthalene, bis(4-aminophenoxy)methane, 1,2-bis(4-aminophenyl)ethane, 1,2-bis(4-aminophenyl)ethane, 1,3-bis(3-aminophenyl)propane, 1,4-bis(4-aminophenyl)butane, 1,4-bis(4-amino-2-methylphenoxy)butane, 1,4-bis(3-aminophenyl)butane, bis(3,5-diethyl-4-aminophenyl)methane, 1,5-bis(4-aminophenoxy)pentane, 1,5-bis(3-aminophenoxy)pentane, 1,6-bis(4-aminophenoxy)hexane, 1,6-bis(3-aminophenoxy)hexane, 1,7-bis(4-aminophenoxy)heptane, 1, 7-bis(3-aminophenoxy)heptane, 1,8-bis(4-aminophenoxy)octane, 1,8-bis(3-aminophenoxy)octane, 1,9-bis(4-aminophenoxy)nonane, 1,9-bis(3-aminophenoxy)nonane, 1,10-bis(4-aminophenoxy)decane, 1,10-bis(3-aminophenoxy)decane, 1,11-bis(4-aminophenoxy)undecane, 1,11-bis(3-aminophenoxy)undecane, 1,12-bis(4-aminophenoxy)dodecane, 1,12-bis(3-aminophenoxy)dodecane, 3-[2-[2-(4-aminophenoxy)ethoxy]ethoxy]aniline, 1,2-bis(6-amino-2-naphthyloxy)ethane, 1,2-Bis(6-amino-2-naphthyl)ethane, 6-[2-(4-aminophenoxy)ethoxy]-2-naphthylamine, 4'-[2-(4-aminophenoxy)ethoxy]-[1,1'-biphenyl]-4-amine, 1,4-bis[2-(4-aminophenyl)ethyl]succinate, 1,6-bis[2-(4-aminophenyl)ethyl]adipate, 2,2-bis(4-aminophenyl)hexafluoropropane, 2,2-bis(3-aminophenyl)hexafluoropropane, 2,2-bis(3-amino-4-methylphenyl)hexafluoropropane, 2,2-bis(4-aminophenyl)propane, 2,2-bis(3-aminophenyl)propane, 2,2 -Diamines having the tetracarboxylic acid diimide structure, such as bis(3-amino-4-methylphenyl)propane, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, and 4,4'-diaminodiphenylmethane; N,N'-bis(4-aminophenyl)-cyclobutane-(1,2,3,4)-tetracarboxylic acid diimide, N,N'-bis(4-aminophenyl)-1,3-dimethylcyclobutane-(1,2,3,4)-tetracarboxylic acid diimide, and N,N'-bis(2,2'-bis(trifluoromethyl)-4'-amino-1,1'-biphenyl-4-yl)-cyclobutane-(1,2,3,4)-tetracarboxylic acid diimide;

[0034] 1,4-Phenylacetyl bis(4-aminobenzoate), 1,4-Phenylacetyl bis(3-aminobenzoate), 1,3-Phenylacetyl bis(4-aminobenzoate), 1,3-Phenylacetyl bis(3-aminobenzoate), bis(4-aminophenyl) terephthalate, bis(3-aminophenyl) terephthalate, bis(4-aminophenyl) isophthalate, bis(3-aminophenyl) isophthalate; 4, 4'-Diaminoazobenzene, diaminodiphenylacetylene, 4,4'-diaminochalcone, or [4-[(E)-3-[2-(2,4-diaminophenyl)ethoxy]-3-sideoxy-prop-1-enyl]phenyl]4-(4,4,4-trifluorobutoxy)benzoate, or [4-[(E)-3-[[5-amino-2-[4-amino-2-[[(E)-3-[4-[4-(4,4,4-trifluorobutoxy) Aromatic diamines with cinnamic acid ester structures, such as benzoyl[oxyphenyl]prop-2-enyl[oxymethyl]phenyl]phenyl]methoxy]-3-sideoxy-prop-1-enyl]phenyl]4-(4,4,4-trifluorobutoxy)benzoate, and other diamines with photoaligning groups; 2-(2,4-diaminophenoxy)ethyl methacrylate or 2,4-diamino-N,N-diallyl aniline, etc., with photopolymerizing groups at the end. Diamines with a synergistic group; diamines with free radical polymerization initiator functions such as 1-(4-(2-(2,4-diaminophenoxy)ethoxy)phenyl)-2-hydroxy-2-methylpropanone, 2-(4-(2-hydroxy-2-methylpropionic)phenoxy)ethyl 3,5-diaminobenzoate; diamines with amide bonds such as 4,4'-diaminobenzoniline; diamines with urea bonds such as 1,3-bis(4-aminophenyl)urea; diamines with thermally detachable groups such as H 2N-Y D-NH 2 (YD represents a divalent organic group with -N(D)- (D represents a protecting group that is removed and substituted into a hydrogen atom by heating);

[0035] 3,3'-Diaminodiphenyl ether, 3,4'-Diaminodiphenyl ether, 4,4'-Diaminodiphenyl ether, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 4,4'-sulfonyldiphenylamine, 3,3'-sulfonyldiphenylamine, bis(4-aminophenoxy)phenyl )Silane, bis(3-aminophenyl)silane, dimethyl-bis(4-aminophenyl)silane, dimethyl-bis(3-aminophenyl)silane, 4,4'-thiodiphenylamine, 3,3'-thiodiphenylamine, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 4,4'-diaminodiphenyl ketone, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 1,4-bis(4-aminobenzyl)benzene;2,6-Diaminopyridine, 3,4-Diaminopyridine, 2,4-Diaminopyrimidine, 3,6-Diaminocarbazole, N-Methyl-3,6-Diaminocarbazole, 1,4-bis-(4-aminophenyl)piperazine, 3,6-Diaminoacridine, N-ethyl-3,6-Diaminocarbazole, N-phenyl-3,6-Diaminocarbazole, N-[3-(1H-imidazol-1-yl)propyl]3,5-diaminobenzamide, 4-[4-[(4-aminophenoxy)methyl]-4,5-dihydro-4-methyl-2-oxazole [4-[4-[(4-aminophenoxy)methyl]-4,5-dihydro-2-oxazolyl]-aniline, 1,4-bis(p-aminobenzyl)piperazine, 4,4'-propane-1,3-diylbis(piperidine-1,4-diyl)diphenylamine, 4-(4-aminophenoxycarbonyl)-1-(4-aminophenyl)piperidine, 2,5-bis(4-aminophenyl)pyrrole, 4,4'-(1-methyl-1H-pyrrole-2,5-diyl)bis[aniline], 1,4-bis-(4-aminophenyl)piperazine, 2-N-(4-aminophenyl)pyridine-2,5-diamine, 2-N-(5-aminopyridin-2-yl)pyridine-2,5-diamine, 2-(4-aminophenyl)-5-aminobenzimidazole, 2-(4-aminophenyl)-6-aminobenzimidazole, 5-(1H-benzimidazol-2-yl)phenyl-1,3-diamine, or heterocyclic diamines such as those represented by formulas (z-1) to (z-5) below, or, in the form of 4,4'-diaminodiphenylamine, 4,4'-diaminodiphenyl-N-methylamine, N, Diamines having a diphenylamine structure, such as N'-bis(4-aminophenyl)-benzidine, N,N'-bis(4-aminophenyl)-N,N'-dimethylbenzidine, or N,N'-bis(4-aminophenyl)-N,N'-dimethyl-1,4-phenylenediamine, are characterized by having at least one nitrogen-containing structure selected from the group consisting of heterocycles, secondary amine groups, or tertiary amine groups (excluding diamines derived from amine groups derived from -N(D)- (where D represents a protecting group that is removed and substituted into a hydrogen atom by heating).

[0036] 2,4-Diaminophenol, 3,5-Diaminophenol, 3,5-Diaminobenzyl alcohol, 2,4-Diaminobenzyl alcohol, 4,6-Diaminoresorcinol, 4,4'-Diamino-3,3'-Dihydroxybiphenyl; 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, Diamines containing carboxyl groups, such as 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'-diaminodiphenyl ether-3,3'-dicarboxylic acid; 1-(4-aminophenyl)-1, 3,3-Trimethyl-1H-indane-5-amine, 1-(4-aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H-indane-6-amine; cholesteryloxy-3,5-diaminobenzene, cholesteryloxy-3,5-diaminobenzene, cholesteryloxy-2,4-diaminobenzene, cholesteryl ester of 3,5-diaminobenzoate, cholesteryl ester of 3,5-diaminobenzoate, cholesteryl ester of 3,5-diaminobenzoate, and lanosteryl ester of 3,6-bis(4-aminobenzoyloxy)cholesteryl Diamines having a steroid skeleton, such as steranes; diamines represented by formulas (V-1) to (V-2) below; diamines having a siloxane bond, such as 1,3-bis(3-aminopropyl)-tetramethyldisiloxane; noncyclic aliphatic diamines such as m-xylene diamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, and hexamethylenediamine; alicyclic diamines such as 1,3-bis(aminomethyl)cyclohexane, 1,4-diaminocyclohexane, and 4,4'-methylenebis(cyclohexylamine); and diamines obtained by bonding two amino groups to a base represented by any one of formulas (Y-1) to (Y-167) as described in WO2018 / 117239.

[0037]

[0038] (In formula (V-1), m and n are integers from 0 to 3 (but satisfy 1≦m+n≦4), j is an integer of 0 or 1, X1 represents -(CH2)a- (a is an integer from 1 to 15), -CONH-, -NHCO-, -CO-N(CH3)-, -NH-, -O-, -CH2O-, -CH2-OCO-, -COO-, or -OCO-, R1 represents a fluorine atom, an alkyl group containing fluorine atoms with 1 to 10 carbon atoms, an alkoxy group containing fluorine atoms with 1 to 10 carbon atoms, an alkyl group with 3 to 10 carbon atoms, an alkoxy group with 3 to 10 carbon atoms, or an alkoxyalkyl group with 3 to 10 carbon atoms; In formula (V-2), X2 represents -O-, -CH2O-, -CH2-OCO-, -COO-, or -OCO-, R 2 represents an alkyl group with 3 to 30 carbon atoms or an alkyl group with 3 to 20 carbon atoms containing fluorine atoms. If there are two of m, n, X1, and R1, they each independently have the above definitions.

[0039] Furthermore, the D in -N(D)- of the aforementioned diamine is preferably a carbamate protecting group, such as benzyloxycarbonyl, 9-pyromethoxycarbonyl, allyloxycarbonyl, or Boc. From the viewpoints of good thermal desorption efficiency, desorption at a lower temperature, and the emission of harmless gases during desorption, Boc is particularly preferred.

[0040] As a preferred example of a diamine having a thermally detachable group, as exemplified by the above-described diamine, it is preferably a diamine selected from the following formulas (d-1) to (d-7). (In formulas (d-2), (d-6), and (d-7), R represents a hydrogen atom or Boc).

[0041] As a diamine component used in the manufacture of polyimide precursor, from the viewpoint that it is suitable to obtain the effects of the present invention, the diamine component is preferably 5 to 40 mol% relative to 1 mol of diamine component, more preferably 5 to 35 mol%, and even more preferably 5 to 30 mol.

[0042] The polymer (A) described above may also contain at least one polymer selected from the group consisting of a polyimide precursor obtained by using a diamine component containing a diamine having a nitrogen-containing structure and a polyimide derivative of the polyimide precursor (hereinafter also referred to as "polyimide polymer (Q)").

[0043] As a tetracarboxylic acid derivative component used to obtain the above-mentioned polyimide polymer (Q), a tetracarboxylic acid derivative component comprising the above-mentioned tetracarboxylic acid dianhydride compound can be used, for example. Among the tetracarboxylic acid dianhydride compounds used to obtain the polyimide polymer (Q), the tetracarboxylic acid dianhydride or its derivative represented by the above formula (2) is preferred. The amount of the tetracarboxylic acid dianhydride or its derivative represented by the above formula (2) used is preferably 10 mol% or more, and more preferably 20 mol% or more, relative to 1 mol of the total tetracarboxylic acid derivative component reacting with the diamine component.

[0044] As the diamine component used to obtain the above-mentioned polyimide polymer (Q), the amount of the diamine having a nitrogen-containing structure used is preferably 5 to 100 mol% relative to the total amount of the diamine component used to obtain the polymer (Q), more preferably 10 to 95 mol%, and even more preferably 20 to 80 mol.

[0045] The diamine component used to obtain the above-mentioned polyimide polymer (Q) may also contain diamines other than those having a nitrogen-containing structure. As a more preferred example, a diamine (hereinafter also referred to as "diamine (c)") having at least one group selected from the group consisting of urea bonds, amide bonds, carboxyl groups, and hydroxyl groups can be cited. The amount of diamine (c) used relative to the total amount of the diamine component used to obtain the polymer (Q) is preferably 1 to 95 mol%, more preferably 5 to 90 mol%, and even more preferably 20 to 80 mol.

[0046] In the polymer (A) of the present invention, the content of carboxyl groups bonded to the aromatic ring is 5 parts by mass or less relative to 100 parts by mass of the polymer. The carboxyl groups bonded to the aromatic ring may be derived from tetracarboxylic acid dianhydride or its derivatives contained in the tetracarboxylic acid derivative component, or may be derived from diamine contained in the diamine component. The content of carboxyl groups bonded to the aromatic ring is preferably 3 parts by mass or less, and more preferably 1 part by mass or less, relative to 100 parts by mass of the polymer. Furthermore, since the polymer (A) of the present invention is "a polymer in which the content of carboxyl groups bonded to the aromatic ring is 5 parts by mass or less relative to 100 parts by mass of the polymer", the selection of the tetracarboxylic acid dianhydride and diamine must be made in a manner that can impart a polymer that satisfies such conditions. In addition, if a polyimide polymer (Q) is contained, the polymer (Q) must also be "in which the content of carboxyl groups bonded to the aromatic ring is 5 parts by mass or less relative to 100 parts by mass of the polymer".

[0047] The (A) component contained in the liquid crystal alignment agent of the present invention may also be a mixture, which is a mixture of at least one polymer (hereinafter also referred to as "polyimide polymer (H)") from the group consisting of the above-mentioned polyimide polymer (Q), a polyimide precursor obtained by using a diamine component that does not contain the above-mentioned diamine having a nitrogen-containing structure, and a polyimide derivative of the polyimide precursor. The content ratio of polyimide polymer (Q) to polyimide polymer (H), in terms of the mass ratio of [polyimide polymer (Q)] / [polyimide polymer (H)], is preferably 10 / 90 to 90 / 10, more preferably 20 / 80 to 80 / 20, and even more preferably 30 / 70 to 70 / 30.

[0048] The liquid crystal alignment agent of the present invention may also contain other polymers besides polymer (A). Specific examples of other polymers include polymers selected from the group consisting of polysiloxanes, polyesters, polyamides, polyureas, polyorganosiloxanes, cellulose derivatives, polyacetals, polystyrene derivatives, poly(styrene-maleic anhydride) copolymers, poly(isobutylene-maleic anhydride) copolymers, poly(vinyl ether-maleic anhydride) copolymers, poly(styrene-phenylmaleimide) derivatives, and poly(meth)acrylates. Specific examples of poly(styrene-maleic anhydride) copolymers include SMA1000, SMA2000, SMA3000 (manufactured by Cray Valley), and GSM301 (manufactured by GSM Corporation); specific examples of poly(isobutylene-maleic anhydride) copolymers include ISOBAM-600 (manufactured by Kuraray Corporation); and specific examples of poly(vinyl ether-maleic anhydride) copolymers include Gantrez AN-139 (methyl vinyl ether maleic anhydride resin, manufactured by Ashland Corporation). Other polymers may be used individually or in combination of two or more. The proportion of other polymers relative to 100 parts by weight of component (A) contained in the liquid crystal alignment agent is preferably 0.1 to 90 parts by weight, more preferably 1 to 90 parts by weight.

[0049] <Method for Manufacturing Polyimide Precursors> Polyamide, as one of the polyimide precursors, can be manufactured by the following method. Specifically, it can be synthesized by reacting a tetracarboxylic acid derivative component containing a tetracarboxylic acid dianhydride with the above-mentioned diamine component in the presence of an organic solvent, preferably at -20 to 150°C, more preferably at 0 to 50°C, more preferably for 30 minutes to 24 hours, and more preferably for 1 to 12 hours (polycondensation reaction).

[0050] Specific examples of organic solvents used in the above reactions include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, and 1,3-dimethyl-2-imidazolinone. Furthermore, if the polymer has high solvent solubility, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, or propylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, diethylene glycol monomethyl ether, or diethylene glycol monoethyl ether may be used. Two or more of these may also be mixed for use.

[0051] The reaction can be carried out at any concentration, preferably 1 to 50% by mass, and more preferably 5 to 30% by mass. A high concentration can be used initially, followed by the addition of solvent. During the reaction, the ratio of the total moles of the diamine components to the total moles of the tetracarboxylic acid derivative components is preferably 0.8 to 1.2. Similar to conventional polycondensation reactions, the closer this mole ratio is to 1.0, the larger the molecular weight of the resulting polyamide.

[0052] The polyacrylic acid obtained from the above reaction can be precipitated and recovered by injecting a poor solvent while thoroughly stirring the reaction solution. Furthermore, after several precipitation cycles and washing with the poor solvent, purified polyacrylic acid powder can be obtained by drying at room temperature or by heating. The poor solvent is not particularly limited and examples include water, methanol, ethanol, hexane, butyl cellosolve, acetone, and toluene.

[0053] Polyamide esters, as one of the precursors of polyimide, can be manufactured by conventional methods such as (1) to (3) below: (1) a method of esterifying the above-mentioned polyamide, (2) a method of reacting a tetracarboxylic acid derivative component containing a tetracarboxylic acid diester dichloride with a diamine component, and (3) a method of polycondensing a tetracarboxylic acid derivative component containing a tetracarboxylic acid diester with a diamine, etc.

[0054] When manufacturing the above-mentioned polyamide and polyamide ester, a suitable end-sealing agent can be used together with the tetracarboxylic acid derivative component and diamine component as described above to obtain an end-modified polymer. Examples of end-sealing agents include, for instance, acetic anhydride, maleic anhydride, nadic anhydride, phthalic anhydride, isocoric anhydride, 1,2-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, 4-ethynyl phthalic anhydride, etc.; dicarbonate ester compounds such as di-tert-butyl dicarbonate and diallyl dicarbonate; chlorocarbonyl compounds such as acrylonitrile chloride, methacrylic acid chloride, and nicotinic acid chloride; aniline, Monoamine compounds such as 2-aminophenol, 3-aminophenol, 4-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 ethyl isocyanate, phenyl isocyanate, naphthyl isocyanate, 2-acryloyloxyethyl isocyanate, and 2-methacryloyloxyethyl isocyanate; and isothiocyanate compounds such as ethyl isothiocyanate and allyl isothiocyanate. The proportion of the end sealant used relative to 100 moles of the total diamine components used is preferably 40 moles or less, and more preferably 30 moles or less.

[0055] <Method for manufacturing polyimide> The polyimide used in this invention can be manufactured by amide imidizing the above-mentioned polyimide precursor using conventional methods. In the polyimide, the ring-closing rate (also referred to as "amide imidization rate") of the functional groups of polyamide acid or polyamide ester is not necessarily 100%, and can be arbitrarily adjusted according to the application or purpose.

[0056] As a method for obtaining polyimide by amide-modifying the above-mentioned polyamide or polyamide, examples include thermal amide-modification by directly heating the above-mentioned polyamide or polyamide solution, or catalytic amide-modification by adding a catalyst (e.g., an alkaline catalyst such as pyridine, an anhydride such as acetic anhydride) to the above-mentioned polyamide or polyamide solution.

[0057] <Polymer Solution Viscosity and Molecular Weight> When the polyamide, polyamide ester, and polyimide used in this invention are set as solutions with a concentration of 10-15% by mass, for example, from an operational point of view, a solution viscosity of 10-1000 mPa·s is preferred, but not particularly limited. Furthermore, the above-mentioned polymer solution viscosity (mPa·s) for a 10-15% by mass polymer solution prepared using a good solvent (e.g., γ-butyrolactone, N-methyl-2-pyrrolidone, etc.) is a value measured using an E-type rotational viscometer at 25°C.

[0058] The weight-average molecular weight (Mw) of the polystyrene-converted polyamide, polyamide ester, and polyimide, as measured by gel permeation chromatography (GPC), is preferably 1,000 to 500,000, and more preferably 2,000 to 500,000. Furthermore, the molecular weight distribution (Mw / Mn), expressed as the ratio of Mw to the number-average molecular weight (Mn) of polystyrene-converted polyamide obtained by GPC measurement, is preferably 15 or less, and more preferably 10 or less. By being within such a molecular weight range, good liquid crystal alignment of the liquid crystal display element can be ensured.

[0059] <<<Compound (B)>>> The liquid crystal alignment agent of the present invention comprises compound (B) represented by formula (1) above. One compound (B) may be used, or two or more compounds may be used. In compound (B), at least one of A2 may be represented by methyl, ethyl, propyl, isopropyl, butyl, or carboxyl. In compound (B), A1 may also have a carboxyl group. Furthermore, A1 may also be a monovalent group represented by "AX-*". (A represents a trialkoxysilyl group; X represents a group consisting of -(CH2)n- (n is an integer from 1 to 18), or at least a portion of the -CH2- of the -(CH2)n- is replaced by any one of -CONH-, -NHCO-, -CO-N(CH3)-, -NH-, -O-, -COO-, or -OCO-, and any hydrogen atom in X may also be replaced by a halogen atom, a carboxyl group, a hydroxyl group, a cyano group, or a nitro group).

[0060] Preferably, the compound represented by formula (1) above is an alkyl-substituted benzotriazole derivative having 1 to 4 carbon atoms, such as benzotriazole, 4-methylbenzotriazole, or 5-methylbenzotriazole, or a benzotriazole derivative containing a monovalent group having a trialkoxysilyl group, such as N-(trimethoxysilyl-propyl)-1H-benzotriazole-1-carbodiamide. Among these, the compounds represented by formulas (b-1) to (b-4) below are even more preferred.

[0061] The amount of the above-mentioned compound (B) contained in the liquid crystal alignment agent of the present invention is preferably 0.1 to 30 parts by mass relative to 100 parts by mass of component (A), more preferably 0.1 to 20 parts by mass, and even more preferably 1 to 10 parts by mass.

[0062] <Liquid Crystal Alignment Agent> The liquid crystal alignment agent is used to manufacture liquid crystal alignment films. From the viewpoint of forming a uniform thin film, it can be in the form of a coating liquid. In the liquid crystal alignment agent of the present invention, a coating liquid containing the above-mentioned component (A), compound (B), and solvent is preferred. The content (concentration) of the polymer component contained in the liquid crystal alignment agent of the present invention can be appropriately changed according to the desired thickness of the coating film. From the point of forming a uniform and defect-free coating film, it is preferred to be 1% by mass or more, and from the point of storage stability of the solution, it is preferred to be 10% by mass or less. From the viewpoint of properly obtaining the effects of the present invention, the total content of polymer (A) in the liquid crystal alignment agent is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, and more preferably 50 parts by mass or more, relative to 100 parts by mass of the total polymer component contained in the liquid crystal alignment agent (p).

[0063] The solvent contained in the liquid crystal alignment agent is not particularly limited, as long as it can uniformly dissolve the polymer components. Specific examples include: N,N-dimethylformamide, N,N-dimethylacetamide, N,N-dimethyllactamamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethyl sulfoxide, γ-butyrolactone, γ-valerolactone, 1,3-dimethyl-2-imidazolinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, 3-methoxy-N,N-dimethylpropionic acid, 3-butoxy-N,N-dimethylpropionic acid, 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, N-cyclohexyl-2-pyrrolidone (these are also collectively referred to as "good solvents"), etc. Among these, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 3-methoxy-N,N-dimethylpropionic acid, 3-butoxy-N,N-dimethylpropionic acid, or γ-butyrolactone are preferred. The content of good solvent is preferably 20 to 99% by mass of the total solvent contained in the liquid crystal alignment agent, more preferably 20 to 90% by mass, and especially preferably 30 to 80% by mass.

[0064] Furthermore, the solvent contained in the liquid crystal alignment agent, in addition to the solvents mentioned above, is preferably a mixed solvent consisting of a solvent that improves the coatability or surface smoothness of the coating film during the application of the liquid crystal alignment agent (also referred to as a "poor solvent"). Specific examples of the poor solvents used are given below, but are not limited to these.

[0065] Examples include: diisopropyl ether, diisobutyl ether, diisobutylmethanol (2,6-dimethyl-4-heptanol), ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, 1,2-dibutoxyethane, 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 monoacetate, ethylene glycol diacetate, propyl carbonate, ethyl carbonate, ethylene glycol monobutyl ether, ethylene glycol monoisopentyl ether, ethylene glycol monohexyl ether, propylene glycol monobutyl ether, 1-(2-butoxyethoxy)-2 Propanol, 2-(2-butoxyethoxy)-1-propanol, propylene glycol monomethyl ether acetate, propylene glycol diacetate, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 2-(2-ethoxyethoxy)ethyl acetate, diethylene glycol acetate, propylene glycol diacetate, n-butyl acetate, propylene glycol monoethyl ether acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, butyl 3-methoxypropionate, n-butyl lactate, isopentyl lactate, diethylene glycol monoethyl ether, diisobutyl ketone (2,6-dimethyl-4-heptanone), etc. The content of undesirable solvent is preferably 1-80% by mass of the total solvent contained in the liquid crystal alignment agent, more preferably 10-80% by mass, and particularly preferably 20-70% by mass. The type and content of undesirable solvent can be appropriately selected according to the coating equipment, coating conditions, coating environment, etc. of the liquid crystal alignment agent.

[0066] Preferably, it is diisobutylmethanol, 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.

[0067] Examples of better solvent combinations between good and poor solvents include: N-methyl-2-pyrrolidone and ethylene glycol monobutyl ether; N-methyl-2-pyrrolidone and γ-butyrolactone and ethylene glycol monobutyl ether; N-methyl-2-pyrrolidone and γ-butyrolactone and propylene glycol monobutyl ether; N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether; N-methyl-2-pyrrolidone and γ-butyrolactone and 4-hydroxy-4-methyl-2-pentanone and diethylene glycol. Diethyl ether; N-methyl-2-pyrrolidone with γ-butyrolactone with propylene glycol monobutyl ether and diisobutyl ketone; N-methyl-2-pyrrolidone with γ-butyrolactone with propylene glycol monobutyl ether and diisopropyl ether; N-methyl-2-pyrrolidone with γ-butyrolactone with propylene glycol monobutyl ether and diisobutylmethanol; N-methyl-2-pyrrolidone with γ-butyrolactone with dipropylene glycol dimethyl ether; N-methyl-2-pyrrolidone with propylene glycol monobutyl ether and dipropylene glycol dimethyl ether, etc.

[0068] The liquid crystal alignment agent of the present invention may also additionally contain components other than polymer components and solvents (hereinafter also referred to as "additive components"). Examples of such additive components include: compounds used to improve the strength of the liquid crystal alignment film (hereinafter also referred to as "crosslinking compounds"); adhesion aids used to improve the adhesion between the liquid crystal alignment film and the substrate or the liquid crystal alignment film and the sealant; dielectric or conductive substances used to adjust the dielectric or resistance of the liquid crystal alignment film; stabilizers used to improve the stability of the varnish; and surfactants or defoamers used to adjust the surface tension of the varnish.

[0069] Examples of the aforementioned crosslinking compounds include at least one crosslinking compound selected from the group consisting of crosslinking compound (c-1) and crosslinking compound (c-2), wherein the crosslinking compound (c-1) has at least one substituent selected from epoxy group, oxetyl group, oxazoline group, cyclic carbonate group, block isocyanate group, hydroxyl group, and alkoxy group; and the crosslinking compound (c-2) has a polymerizable unsaturated group. Preferred examples of the aforementioned crosslinking compounds (c-1) and (c-2) include the following compounds. Examples of compounds containing epoxy groups 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, glycerol diglycidyl ether, dibromonepentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol, bisphenol A type epoxy resins such as Epikote 828 (manufactured by Mitsubishi Chemical Co., Ltd.), bisphenol F type epoxy resins such as Epikote 807 (manufactured by Mitsubishi Chemical Co., Ltd.), hydrogenated bisphenol A type epoxy resins such as YX-8000 (manufactured by Mitsubishi Chemical Co., Ltd.), and YX6954BH30 (manufactured by Mitsubishi Chemical Co., Ltd.). Compounds containing a biphenyl skeleton, such as epoxy resins (manufactured by Chemical Co., Ltd.), phenolic varnish epoxy resins such as EPPN-201 (manufactured by Nippon Kayaku Co., Ltd.), (o, m, p-)cresol varnish epoxy resins such as EOCN-102S (manufactured by Nippon Kayaku Co., Ltd.), tetra(glycidyloxymethyl)methane, N,N,N',N'-tetraglycidyl-1,4-phenylenediamine, N,N,N',N'-tetraglycidyl-2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2-bis[4-(N,N-diglycidyl-4-aminophenoxy)phenyl]propane, N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, etc., in which tertiary nitrogen atoms are bonded to aromatic carbon atoms;N,N,N',N'-Tetraglycidyl-1,2-diaminocyclohexane, N,N,N',N'-Tetraglycidyl-1,3-diaminocyclohexane, N,N,N',N'-Tetraglycidyl-1,4-diaminocyclohexane, bis(N,N-diglycidyl-4-aminocyclohexyl)methane, bis(N,N-diglycidyl-2-methyl-4-aminocyclohexyl)methane, bis(N,N-diglycidyl-3-methyl-4-aminocyclohexyl)methane, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, 1,4-bis(N,N-diglycidylaminomethyl)cyclohexane Compounds of alkyl, 1,3-bis(N,N-diglycidylaminomethyl)benzene, 1,4-bis(N,N-diglycidylaminomethyl)benzene, 1,3,5-tris(N,N-diglycidylaminomethyl)cyclohexane, 1,3,5-tris(N,N-diglycidylaminomethyl)benzene, etc., in which tertiary nitrogen atoms are bonded to aliphatic carbon atoms; isocyanurate compounds such as triglycidyl isocyanurate from TEPIC (manufactured by Nissan Chemical Co., Ltd.); compounds described in paragraph

[0037] of Japanese Patent Application Publication No. 10-338880; or compounds described in Publication No. WO2017 / 170483, etc. Examples of compounds having oxetane groups include: 1,4-bis{[(3-ethyl-3-oxetane)methoxy]methyl}benzene (ARON Oxetane OXT-121(XDO)), bis[2-(3-oxetane)butyl]ether (ARON Oxetane OXT-221(DOX)), 1,4-bis[(3-ethyloxetane-3-yl)methoxy]benzene (HQOX), 1,3-bis[(3-ethyloxetane-3-yl)methoxy]benzene (RSOX), 1,2-bis[(3-ethyloxetane-3-yl)methoxy]benzene (CTOX), and compounds having two or more oxetane groups as described in paragraphs

[0170] to

[0175] of WO2011 / 132751. Examples of compounds having an oxazoline structure include compounds such as 2,2'-bis(2-oxazoline) and 2,2'-bis(4-methyl-2-oxazoline), polymers or oligomers having an oxazoline group such as EPOCROS (trade name, Nippon Shokubai Corporation), and compounds described in paragraph

[0115] of Japanese Patent Application Publication No. 2007-286597. Examples of compounds having cyclic carbonate groups include, for example, N,N,N',N'-tetratetra[(2-sideoxy-1,3-dioxolane-4-yl)methyl]-4,4'-diaminodiphenylmethane, N,N',-di[(2-sideoxy-1,3-dioxolane-4-yl)methyl]-1,3-phenylenediamine, or the compounds described in paragraphs

[0025] to

[0030] and

[0032] of WO2011 / 155577.Examples of compounds having block isocyanate groups include: CORONATE AP stable M, CORONATE 2503, 2515, 2507, 2513, 2555, Millionate MS-50 (all manufactured by Tosoh Corporation), TAKANATE B-830, B-815N, B-820NSU, B-842N, B-846N, B-870N, B-874N, B-882N (all manufactured by Mitsui Chemicals Corporation), compounds having two or more protected isocyanate groups as described in paragraphs

[0046] to

[0047] of Japanese Patent Application Publication No. 2014-224978, and compounds having three or more protected isocyanate groups as described in paragraphs

[0119] to

[0120] of WO2015 / 141598. Examples of compounds having hydroxyl and / or alkoxy groups include: N,N,N',N'-tetra(2-hydroxyethyl)hexamethylenediamine, 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-dihydroxymethylphenyl)-1,1,1,3,3,3-hexafluoropropane, compounds described in paragraph

[0058] of Japanese Patent Application Publication No. WO2015 / 072554 or Japanese Patent Application Publication No. 2016-118753, compounds described in Japanese Patent Application Publication No. 2016-200798, compounds described in Japanese Patent Application Publication No. WO2010 / 074269, etc. Examples of crosslinkable compounds with polymerizable unsaturated groups include: glycerol mono(meth)acrylate, glycerol di(meth)acrylate (a mixture of 1,2- and 1,3-dimeth)acrylate, glycerol tri(meth)acrylate, glycerol 1,3-diglyceride 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, hexaethylene glycol mono(meth)acrylate, etc.

[0070] The above-mentioned compounds are examples of cross-linking compounds, but are not limited to them. Examples include other components not disclosed in paragraphs

[0105] on page 53 to

[0116] of WO2015 / 060357. Furthermore, two or more cross-linking compounds may be combined.

[0071] When a crosslinking compound is used, the content of the crosslinking compound in the liquid crystal alignment agent is preferably 0.5 to 20 parts by mass, and more preferably 1 to 15 parts by mass, relative to 100 parts by mass of the polymer component contained in the liquid crystal alignment agent.

[0072] Examples of the above-mentioned adhesion promoters include: 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-ureapropyltrimethoxysilane, 3-ureapropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyl Trimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-3-triethoxysilylpropyltriethylenetetramine, N-3-trimethoxysilylpropyltriethylenetetramine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonylacetate, 9-triethoxysilyl-3,6-diazanonylacetate, N-benzyl-3-aminopropyltrimethoxysilane Oxylated silanes, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p -Silane coupling agents such as styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, tris(3-trimethoxysilylpropyl)isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-isocyanatepropyltriethoxysilane. When an adhesion promoter is used, the amount of the adhesion promoter in the liquid crystal alignment agent is preferably 0.1 to 30 parts by weight, and more preferably 0.1 to 20 parts by weight, relative to 100 parts by weight of the polymer component contained in the liquid crystal alignment agent.

[0073] In order to improve the stability of the varnish, a stabilizer may also be added to the composition of the present invention. Specific examples of stabilizers include polyol compounds described in WO2011 / 129414 or amine compounds described in WO2021 / 171939.

[0074] In the composition of the present invention, surfactants or defoamers may be added for the purpose of adjusting the surface tension of the varnish. Generally known surfactants may be used as long as they do not separate from the polymer or solvent. As surfactants, cationic surfactants, anionic surfactants, and nonionic surfactants may be used, with nonionic surfactants being preferred.

[0075] Specific examples of nonionic surfactants (hereinafter referred to as trade names) include: MEGAFACE (registered trademark) F-251, F-253, F-281, F-430, F-477, F-551, F-552, F-553, F-554, F-555, F-556, F-557, F-558, F-559, F-560, F-561, F-562, F-563, F- 565, F-568, F-569, F-570, F-572, F-574, F-575, F-576, R-40, R-40-LM, R-41, R-94, RS-56, RS-72-K, RS-75, RS-76-E, RS-76-NS, RS-78, RS-90, DS-21 (DIC (stock)), FC-4432 (Sumitomo 3M (stock)), Surflon (registered trademark) S-242, S-243, S-420, S-431, S-386, S-611, S-647, S-651, S-653, S-656, S-658, S-693, S-CFJ (Asahi Glass (stock)), etc., but not limited to these.

[0076] Furthermore, as a defoamer, polysiloxane defoamers, acrylic polymer defoamers, vinyl ether polymer defoamers, etc., can be used, but are not limited to these.

[0077] Specific examples of defoamers include: KF-96, KF-6701, KS-7708, KS-66, KS-69, KS-7716, KS-602A, FA-600, X-50-1110D, KM-601S (Shin-Etsu silicone), Flowlen AC-230, AC-262H, AC-300, AC-303, AC-326F, AO-106, AO-108, AO-108AF (made by Gyoeisha Chemical Co., Ltd.), BYK-051N, BYK-052N, BYK-0 53N, BYK-054, BYK-055, BYK-057, BYK-070, BYK-072, BYK-077, BYK-081, BYK-085, BYK-141, BYK-1681, BYK-1692S D. BYK-1709, BYK-1751, BYK-1752, BYK-1758, BYK-1759, BYK-1760, BYK-1795, BYK-1796, BYK-1797, BYK-1799, BY K-A500, BYK-A501BYK-A505, BYK-A506, BYK-A515, BYK-A525, BYK-A530, BYK-A535, BYK-A550, BYK-A555, BYK-A560 (BYK JAPAN Co., Ltd.), etc., but are not limited to these.

[0078] Also, the surfactant or defoamer can be used alone or in combination of several types, and the amount added is preferably less than 5 parts by weight relative to 100 parts by weight of the polymer.

[0079] (Liquid Crystal Alignment Film) The liquid crystal alignment film of the present invention is formed using the liquid crystal alignment agent of the present invention described above. The manufacturing method of the liquid crystal alignment film of the present invention includes, for example, coating the liquid crystal alignment agent onto a substrate, firing, and irradiating the obtained film with polarized radiation. As a preferred embodiment of the manufacturing method of the liquid crystal alignment film of the present invention, a manufacturing method of the liquid crystal alignment film may include, for example, the following steps: coating the liquid crystal alignment agent onto a substrate (step (1)), firing the coated liquid crystal alignment agent (step (2)), and performing alignment treatment on the film obtained in step (2) as appropriate (step (3)).

[0080] <Step (1)> As the substrate for coating the liquid crystal alignment agent used in this invention, any highly transparent substrate is acceptable and is not particularly limited. Plastic substrates such as glass substrates, silicon nitride substrates, acrylic substrates, or polycarbonate substrates can also be used. In this case, it is preferable to use a substrate with ITO (Indium Tin Oxide) electrodes for liquid crystal driving, etc., for the purpose of simplifying the manufacturing process. Furthermore, in reflective liquid crystal display elements, when the substrate is limited to one side, opaque materials such as silicon wafers can also be used. In this case, the electrodes can also be light-reflecting materials such as silver, aluminum, nickel, or alloys containing any of the aforementioned metals.

[0081] Methods for coating a liquid crystal alignment agent onto a substrate and forming a film include screen printing, flatbed printing, flexographic printing, inkjet printing, and spray printing. Among these, inkjet printing is a suitable coating and film forming method.

[0082] <Step (2)> Step (2) is the step of firing the liquid crystal alignment agent coated on the substrate to form a film. After coating the liquid crystal alignment agent on the substrate, the solvent can be evaporated or the amide or amide ester in the polymer can be thermally amide-imidized by heating means such as a heating plate, a thermal cycling oven or an IR (infrared) oven. The drying and firing steps after coating the liquid crystal alignment agent of the present invention can be performed at any temperature and time, and can be repeated multiple times. For example, the temperature for evaporating the solvent of the liquid crystal alignment agent can be 40~180°C. From the viewpoint of shortening the process, it can also be performed at 40~150°C. The firing time is not particularly limited, and can be 1~10 minutes or 1~5 minutes. When the amide or amide ester in the polymer is thermally amide-imidized, after the solvent evaporation step described above, a firing step can be performed at a temperature range of, for example, 150-300°C or 150-250°C. The firing time is not particularly limited, but examples include 5-40 minutes or 5-30 minutes. If the fired film is too thin, it will reduce the reliability of the liquid crystal display element; therefore, a thickness of 5-300 nm is preferred, and more preferably 10-200 nm.

[0083] <Step (3)> Step (3) is a step of aligning the film obtained in step (2) according to the situation. For liquid crystal display elements of the transverse electric field type such as IPS or FFS, alignment energy can be imparted by performing an alignment energy imparting treatment on the formed coating. For vertical alignment type liquid crystal display elements such as VA or PSA, the formed coating can be used directly as a liquid crystal alignment film, but alignment energy imparting treatment can also be applied to the coating. The alignment treatment method for the liquid crystal alignment film can be a rubbing treatment method or a photoalignment treatment method. As a photoalignment treatment method, the following method can be cited, but is not particularly limited to: irradiating the surface of the above film with radiation that has been polarized to a certain direction, and performing a heating treatment as appropriate, to impart liquid crystal alignment properties (also called "liquid crystal alignment energy").

[0084] (Liquid Crystal Display Element) The liquid crystal display element of the present invention includes the liquid crystal alignment film of the present invention. From the viewpoint of obtaining high liquid crystal alignment, the liquid crystal alignment film of the present invention is suitable as a liquid crystal alignment film for liquid crystal display elements with vertical alignment methods such as VA or PSA, but is not particularly limited thereto.

[0085] A liquid crystal display element can be manufactured by obtaining a substrate with a liquid crystal alignment film from the liquid crystal alignment agent of the present invention, fabricating a liquid crystal cell using conventional methods, and placing liquid crystal within the liquid crystal cell. Specifically, the following two methods can be cited.

[0086] The first method is as follows: First, two substrates are arranged facing each other with separate liquid crystal alignment films facing each other, separated by a gap (cell spacing). Next, the peripheries of the two substrates are bonded together using a sealant, and liquid crystal composition is injected into the cell spacing separated by the substrate surface and the sealant. After the liquid crystal composition comes into contact with the film surface, the injection hole is sealed.

[0087] The second method is called the ODF (One Drop Fill) method. On one side of two substrates with a liquid crystal alignment film, a sealant, such as one that can be cured by ultraviolet light, is applied to designated areas. Then, liquid crystal composition is dropped onto several designated areas on the surface of the liquid crystal alignment film. Next, the other substrate is bonded with the liquid crystal alignment films facing each other, allowing the liquid crystal composition to diffuse across the entire surface of the substrate and contact the film surface. Finally, the entire surface of the substrate is irradiated with ultraviolet light to cure the sealant.

[0088] Regardless of whether the first or second method is used, it is preferable to further heat the liquid crystal composition to a temperature that makes it a homogeneous phase, and then slowly cool it to room temperature to remove the flow alignment during liquid crystal filling. Furthermore, when performing a rubbing treatment on the coating, the two substrates are arranged facing each other with the rubbing directions in each coating forming mutually designated angles (e.g., orthogonal or antiparallel). Similarly, when performing a photoalignment treatment, the substrates are arranged facing each other with the alignment directions forming mutually designated angles (e.g., orthogonal or antiparallel). As a sealant, epoxy resin containing a hardener and alumina balls as spacers can be used. As a liquid crystal, nematic liquid crystals and lamellar liquid crystals can be cited, with nematic liquid crystals being preferred.

[0089] Regarding the liquid crystal material, either positive or negative liquid crystal materials can be used, but negative liquid crystal materials are preferred. [Example]

[0090] The following examples illustrate the invention in more detail, but the invention is not limited thereto. The abbreviated symbols for the compounds described below are as follows.

[0091] (Organic solvent) NMP: N-methyl-2-pyrrolidone BCS: Butyl cellosolve (diamine) DA-1~DA-5: Compounds represented by formulas (DA-1)~(DA-5) (tetracarboxylic acid dianhydrides) DAH-1~DAH-4: Compounds represented by formulas (DAH-1)~(DAH-4) (benzotriazole additives) B-1~B-2: Compounds represented by formulas (B-1)~(B-2) (crosslinking agents) C-1: Compound represented by formula (C-1) (stabilizer) D-1~D-2: Compounds represented by formulas (D-1)~(D-2) (surfactants) E-1: F-563 (manufactured by DIC, nonionic oligomer containing fluorinated and lipophilic groups) (Other additives) F-1 to F-4: Compounds represented by formulas (F-1) to (F-4) respectively.

[0092]

[0093]

[0094]

[0095]

[0096]

[0097]

[0098] <Measurement of Acrylimide Ratio> Prepare a solution with a solid fraction concentration of 8% by mass, obtained by dissolving polyimide powder in NMP, and measure 0.38 g of NMP solution. Add 1.0 mL of dimethyl sulfoxide (DMSO-d6, 0.05% TMS mixture) to this solution and homogenize it, then place it into an NMR sample tube (Kusano Scientific NMR sampling tube stand ϕ5). Measure proton NMR at 500 MHz using a JEOL DATUM NMR analyzer (JNW-ECA500). The acetylation ratio is obtained as follows: using the proton from the unchanged structure before and after acetylation as the reference proton, the peak accumulation value of this proton, and the peak accumulation value of the protons originating from the NH group of acetylic acid appearing around 9.5 ppm to 10.0 ppm, can be obtained by the following formula. In the following formula, x represents the cumulative proton peak value derived from the NH group of acetic acid, y represents the cumulative peak value of the reference proton, and α represents the ratio of the number of reference protons to the number of NH protons of one acetic acid when polyacetic acid (aceimidization rate is 0%). Acetimization rate (%) = (1 - α・x / y) × 100

[0099] <Calculation of the percentage of carboxyl groups (hereinafter also referred to as "aromatic carboxyl groups") bonded to aromatic rings in polymers> Focusing on the mass ratio of carboxyl groups in compounds containing aromatic carboxyl groups, the percentage of aromatic carboxyl groups in the polymer is calculated. For example, when a polyamide containing only DA-5 as an aromatic carboxyl group is set as a polymer component, the calculation is performed according to the following formula. Percentage of aromatic carboxyl groups in the polymer [%] = Molecular weight of carboxyl group (45.0) × Percentage of DA-5 in total diamine ÷ (Average molecular weight of dianhydride monomer + Average molecular weight of diamine monomer)

[0100] <Manufacturing Example> (Manufacturing Example 1) DA-1 (15.22 g, 40 mmol) was added to a 200 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube. Then, NMP (74.3 g) was added, and nitrogen was introduced while stirring to dissolve it. While stirring the diamine solution, DAH-1 (7.72 g, 39 mmol) was added. Then, NMP (17.4 g) was added, and the mixture was further stirred at 40 °C for 20 hours to obtain a polyamide solution (PAA-1) with a solid fraction concentration of 20% by mass.

[0101] (Manufacturing Example 2) 30 g (10.4 mmol) of polyacrylic acid solution PAA-1 was measured into a 100 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube. 36.7 g of NMP was added to bring the solid content to 9% by mass, and the mixture was stirred for 30 minutes. 2.3 g (based on a polyacrylic acid molar ratio of 2.2) of acetic anhydride and 0.4 g (based on a polyacrylic acid molar ratio of 0.5) of pyridine were added to the obtained polyacrylic acid solution. The mixture was stirred at room temperature for 30 minutes and then heated at 55°C for 4 hours to perform chemiimidation. The resulting reaction solution was added to 300 mL of methanol while stirring. The precipitate was filtered out. The resin powder was washed by performing the same operation twice and then dried at 100°C for 8 hours to obtain polyimide resin powder. 5.0 g of the obtained polyimide resin powder was measured into a 100 mL Erlenmeyer flask, and NMP was added at a solids concentration of 8%. The mixture was stirred at 50 °C for 24 hours to dissolve the powder, thus obtaining a polyimide solution (PI-1-a). The amide content of the polyimide resin was 85%.

[0102] (Manufacturing Example 3) Using 30 g (10.4 mmol) of PAA-1, a polyimide solution (PI-1-b) was obtained using the same method as in Manufacturing Example 2. However, the solid fraction concentration during chemiimidation was set to 6.5% by mass, the amount of acetic anhydride used was 2.7 g (based on a polyimide molar ratio of 2.5), and the amount of pyridine used was 1.6 g (based on a polyimide molar ratio of 2.0). The heating conditions were set at 50°C for 2 hours. The chemiimidation rate of the obtained polyimide resin was 81%.

[0103] (Manufacturing Example 4) Using 30 g (10.4 mmol) of PAA-1, a polyimide solution (PI-1-c) was obtained using the same method as in Manufacturing Example 3. However, the heating conditions were set at 50°C for 1 hour and 45 minutes. The polyimide resin obtained had an imidization rate of 74%.

[0104] (Manufacturing Example 5) Using 30 g (10.4 mmol) of PAA-1, a polyimide solution (PI-1-d) was obtained using the same method as in Manufacturing Example 3. However, the heating conditions were set at 50°C for 1 hour and 30 minutes. The polyimide resin obtained had an imidization rate of 63%.

[0105] (Manufacturing Example 6) Using 30 g (10.4 mmol) of PAA-1, a polyimide solution (PI-1-e) was obtained using the same method as in Manufacturing Example 3. However, the heating conditions were set at 50°C for 1 hour. The polyimide resin obtained had an imidization rate of 54%.

[0106] (Manufacturing Example 7) DA-1 (9.51 g, 25 mmol) and DA-2 (2.70 g, 25 mmol) were added to a 200 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube. Then, NMP (28.5 g) was added, and nitrogen was introduced while stirring to dissolve the diamine solution. While stirring the solution, DAH-2 (2.24 g, 10 mmol) was added, followed by NMP (15.7 g), and the mixture was further stirred at 60 °C for 3 hours. The solution was cooled to room temperature, and DAH-1 (7.75 g, 39.5 mmol) was added while stirring, followed by NMP (45.7 g), and the mixture was further stirred at 40 °C for 12 hours to obtain a polyacrylic acid solution (PAA-2) with a solid fraction concentration of 20% by mass.

[0107] (Manufacturing Example 8) Using 10 g (4.4 mmol) of PAA-2, a polyimide solution (PI-2) was obtained using the same method as in Manufacturing Example 3. However, the acetic anhydride used in the chemiimidation was set to 2.3 g (based on a polyimide molar ratio of 5.0) and the pyridine was set to 0.7 g (based on a polyimide molar ratio of 2.0). The heating conditions were set to 50°C for 3 hours. The chemiimidation rate of the obtained polyimide resin was 75%.

[0108] (Manufacturing Example 9) DA-1 (9.51 g, 25 mmol) and DA-2 (2.70 g, 25 mmol) were added to a 200 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube. Then, NMP (28.5 g) was added and stirred while introducing nitrogen to dissolve the diamine solution. While stirring the solution, DAH-3 (2.50 g, 10 mmol) was added, followed by NMP (15.7 g), and the mixture was stirred at 80 °C for 5 hours. The solution was cooled to room temperature, and DAH-1 (7.75 g, 39.5 mmol) was added while stirring. Then, NMP (45.7 g) was added, and the mixture was stirred at 40 °C for 12 hours to obtain a polyacrylic acid solution (PAA-3) with a solids concentration of 20% by mass.

[0109] (Manufacturing Example 10) Using 10 g (4.4 mmol) of PAA-3, a polyimide solution (PI-3) was obtained using the same method as in Manufacturing Example 3. However, the acetic anhydride used in the chemiimidation was set to 2.3 g (based on a polyimide molar ratio of 5.0) and the pyridine was set to 0.9 g (based on a polyimide molar ratio of 2.5). The heating conditions were set to 60°C for 4 hours. The chemiimidation rate of the obtained polyimide resin was 81%.

[0110] (Manufacturing Example 11) DA-3 (3.89 g, 36 mmol) and DA-4 (1.39 g, 4 mmol) were added to a 200 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube. Then, NMP (25.8 g) was added, and nitrogen was introduced while stirring to dissolve the diamine solution. While stirring the diamine solution, DAH-4 (11.77 g, 39.2 mmol) was added, followed by NMP (42.4 g). The mixture was then stirred at room temperature for 20 hours to obtain a polyacrylic acid solution (PAA-4) with a solid fraction concentration of 20% by mass.

[0111] (Manufacturing Example 12) 10g of PAA-4 was used, and chemical amide oxidation was carried out using a well-known method. The resulting powder was dissolved in NMP to obtain a polyamide solution (PI-4) with a solids concentration of 8% by mass. The amide oxidation rate of the obtained polyamide resin was 88%.

[0112] (Manufacturing Example 13) DA-1 (4.57 g, 12 mmol) and DA-5 (4.26 g, 28 mmol) were added to a 200 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube. Then, NMP (43.1 g) was added and stirred while introducing nitrogen to dissolve the diamine solution. While stirring the solution, DAH-3 (7.51 g, 30 mmol) was added, followed by NMP (5.9 g), and the mixture was stirred at 80 °C for 5 hours. The solution was cooled to room temperature, and DAH-1 (1.88 g, 9.6 mmol) was added while stirring. Then, NMP (23.9 g) was added, and the mixture was stirred at 40 °C for 12 hours to obtain a polyacrylic acid solution (PAA-5) with a solid fraction concentration of 20% by mass.

[0113] (Manufacturing Example 14) 10g of PAA-5 was used, and chemical amide oxidation was carried out using a well-known method. The resulting powder was dissolved in NMP to obtain a polyamide solution (PI-5) with a solids concentration of 8% by mass. The amide oxidation rate of the obtained polyamide resin was 81%.

[0114] <Example 1> In a sample tube containing a stir bar, a solution of polyimide solution (PI-1-a) obtained in Synthesis Example 1, NMP, and BCS were added. Additives B-1 and C-1 were added in a manner that yielded 6 parts by mass and 3 parts by mass respectively, relative to 100 parts by mass of polymer solids. The mixture was stirred for 30 minutes. After stirring, a liquid crystal alignment agent (A1) with a polyimide solution (PI-1-a) solids concentration of 4.5% by mass and a solvent composition of NMP:BCS = 60:40 by mass was obtained.

[0115] <Examples 2-12, Comparative Examples 1-9> Except that the types and amounts of polymer components and additives used were changed as described in Table 1 below, liquid crystal alignment agents (A2)-(A12) and (X1)-(X9) were obtained using the same method as in Example 1. The values ​​(B)-(F) in Table 1 represent the mixing ratio (parts by mass) of additives relative to 100 parts by mass of the total polymer component (A) used in the modulation of the respective liquid crystal alignment agents.

[0116] <Preparation of Samples for Migration Resistance Evaluation> A silver pattern 2, as shown in Figure 1, is prepared on a glass substrate 1 by vapor deposition. The silver thickness is set to 100 nm. A clear coat of liquid crystal alignment agents (A1)~(A12) and (X1)~(X9) is spin-coated onto the glass substrate with the silver pattern. First, it is pre-baked at 80°C for 2 minutes. Next, it is baked at 120°C for 5 minutes to prepare a liquid crystal alignment film 3 with a thickness of approximately 300 nm. Conductive tape 4 is attached to both ends of the electrodes to obtain the evaluation sample. A cross-sectional view of the silver pattern substrate with the hardened film is shown in Figure 2. The migration resistance of the obtained sample is evaluated using the following method.

[0117] <Migration Resistance Assessment> The migration resistance assessment sample prepared above was placed under conditions of 85°C and 85% RH. A test was conducted in which the anode and cathode were connected, and a voltage of 50V was applied to both ends of the silver pattern for 50 hours to induce an electric field concentration at the top of the pattern. This was to confirm whether migration occurred due to the test. Furthermore, the top of the pattern after the test was observed under a microscope to confirm whether migration had occurred. The patterns after the test are shown in Figures 3 and 4. As shown in Figure 3, the situation where no precipitation was observed after applying voltage was defined as "○"; as shown in Figure 4, the situation where precipitation occurred was defined as "×", for evaluation.

[0118] <Fabrication of Liquid Crystal Display Element> The obtained liquid crystal alignment agent was spin-coated onto the ITO surface of a glass substrate with a transparent electrode composed of an ITO film. After drying on a hot plate at 80°C for 2 minutes, it was fired on a hot plate at 120°C for 5 minutes to obtain a substrate with a liquid crystal alignment film (film thickness 100nm). Two substrates with the liquid crystal alignment film were prepared and rubbed with their alignment directions aligned at 180°. The rubbing cloth used was Yoshikawa Chemical's YA-20R rayon cloth with a roller diameter of 120mm. The rubbing was performed under the conditions of 1000rpm rotation, 25mm / sec movement speed, and 0.3mm indentation. After the rubbing, the substrate was ultrasonically cleaned in pure water for 1 minute and dried at 80°C for 15 minutes. For the substrate with one side having undergone friction treatment, 6μm bead spacers are dispersed on the liquid crystal alignment film. Then, a sealant (Mitsui Chemicals, XN-1500T) is applied in a shape resembling the residual liquid crystal injection port. Next, the other side of the substrate is bonded together with the liquid crystal alignment film surfaces facing each other and the alignment direction at 180°. Afterward, the sealant is heat-cured by heating at 80°C for 15 minutes, followed by heating at 100°C for 90 minutes. The substrate is then cooled at room temperature to form an empty cell. Liquid crystal (Merck, MLC-3022) is injected into this empty cell using a reduced-pressure injection method, sealing the injection port to form the liquid crystal cell.

[0119] <Voltage Retention Rate (VHR) Evaluation> The voltage retention rate is evaluated as follows: A voltage of 1V is applied to the obtained liquid crystal cell at a temperature of 60°C for 60μs, and the voltage is measured after 1667ms. The voltage retention rate is calculated as the amount of voltage that can be maintained (i.e., the change from the initial value). The voltage retention rate is measured using a VHR-1 voltage retention rate measuring device manufactured by TOYO Corporation. A VHR of 80% or higher under the above conditions is defined as "○"; a VHR of less than 80% is defined as "×".

[0120] The results of migration resistance evaluation and voltage retention rate evaluation are shown in Table 2. All liquid crystal alignment films using the liquid crystal alignment agents shown in the examples showed good migration resistance evaluation. Furthermore, F-4, which is included in the same range as B-1 and B-2 within the compound (B) of the present invention, is known as a rust inhibitor. In Comparative Example 7 using F-4 as an additive, the voltage retention rate was poor, but in Examples 2 and 8 using B-1 and B-2, the voltage retention rate was good. Moreover, even when using B-2, Comparative Example 9, where the content of carboxyl groups bonded to the aromatic ring is greater than 5 parts by mass, showed poor migration resistance evaluation.

[0121]

[0122] Shang, the entire contents of the specification, claims, drawings and abstract of Japanese Patent Application No. 2022-23238, filed on February 17, 2022, are hereby incorporated as disclosure of the present invention. [Simplified Explanation of the Diagram]

[0014] [Figure 1] Top view of the glass substrate with the silver pattern. [Figure 2] Cross-sectional view of the silver pattern substrate with a hardened film. [Figure 3] Enlarged view of the top of the pattern after voltage application (passing). [Figure 4] Enlarged view of the top of the pattern after voltage application (failing).

Claims

1. A liquid crystal alignment agent comprising the following component (A) and a compound (B) represented by the following formula (1), wherein the content of the aforementioned compound (B) is 0.1 to 30 parts by mass relative to 100 parts by mass of the aforementioned component (A). Component (A) is a polymer selected from the group consisting of a polyimide precursor obtained by polymerizing a tetracarboxylic acid derivative component and a diamine component, and a polyimide as a polyimide precursor, wherein the tetracarboxylic acid derivative component comprises at least one compound selected from the group consisting of tetracarboxylic acid dianhydrides and their derivatives, and the content of a carboxyl group bonded to an aromatic ring is 5 parts by mass or less relative to 100 parts by mass of the polymer. (A1 is a monovalent group represented by "AX-*", where A represents a trialkoxysilyl group; X represents a group where at least a portion of the -CH2- of the -(CH2)n- (n is an integer from 1 to 18) is replaced by any one of -CONH-, -NHCO-, -CO-N(CH3)-, -NH-, -O-, -COO-, or -OCO-; any hydrogen atom in X may also be replaced by a halogen atom, carboxyl group, hydroxyl group, cyano group, or nitro group; * indicates the bond position; A2 independently represents an alkyl group, carboxyl group, or hydrogen atom with 1 to 4 carbon atoms).

2. The liquid crystal alignment agent as claimed in claim 1, wherein, The aforementioned compound (B) is represented by the following formula (b-2).

3. The liquid crystal alignment agent as claimed in claim 1, wherein, In the aforementioned component (A), the aforementioned diamine component contains a diamine having a structure having at least one nitrogen-containing atom selected from the group consisting of a heterocycle containing a nitrogen atom, a secondary amino group, or a tertiary amino group.

4. The liquid crystal alignment agent as claimed in claim 1, wherein, In the aforementioned component (A), the aforementioned tetracarboxylic acid derivative component includes a tetracarboxylic acid dianhydride represented by the following formula (2), (X represents a structure selected from the group consisting of the following formulas (x-1)~(x-17) and (xr-1)~(xr-2)) (R1~R4 independently represent hydrogen atom, halogen atom, alkyl group having 1~6 carbon atoms, alkenyl group having 2~6 carbon atoms, alkynyl group having 2~6 carbon atoms, monovalent organic group having 1~6 carbon atoms containing fluorine atom, alkoxy group having 1~6 carbon atoms, alkoxyalkyl group having 2~6 carbon atoms, alkyloxycarbonyl group having 2~6 carbon atoms, or phenyl group; R5 and R6 independently represent hydrogen atom or methyl group; *1 is a bond bonded to one anhydride group; *2 is a bond bonded to the other anhydride group).

5. The liquid crystal alignment agent as claimed in claim 1, wherein, It further contains additives selected from crosslinking compounds, adhesion promoters, dielectric or conductive substances used to adjust the dielectric or resistance of liquid crystal alignment films, stabilizers, surfactants, and defoamers.

6. A method for manufacturing a liquid crystal alignment film, comprising: coating a liquid crystal alignment agent of any one of claims 1 to 5 onto a substrate, firing it, and irradiating the resulting film with polarized radiation.

7. A method for manufacturing a liquid crystal alignment film, comprising: coating a liquid crystal alignment agent of any one of claims 1 to 5 onto a substrate, firing, and rubbing the resulting film.

8. A liquid crystal alignment film formed from any one of the liquid crystal alignment agents in claims 1 to 5.

9. A method for manufacturing the liquid crystal alignment film as claimed in claim 6 or 7, wherein, In the aforementioned substrate, electrodes or wiring containing silver are disposed on the coating surface of the liquid crystal alignment agent.

10. A liquid crystal display element comprising the liquid crystal alignment film of claim 8.

11. The liquid crystal display element as claimed in claim 10, wherein, Materials containing silver are used as electrodes and / or wiring for liquid crystal display elements.

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