Liquid crystal alignment agents, liquid crystal alignment films, liquid crystal display elements, compounds, and polymers

Abstract

The present invention provides a liquid crystal alignment agent capable of obtaining a liquid crystal alignment film with small variation (non-uniformity) of the torsion angle of liquid crystal within the liquid crystal alignment film surface, a liquid crystal alignment film obtained from the liquid crystal alignment agent, a liquid crystal display element using the liquid crystal alignment film, and compounds and polymers that can be used therein. A liquid crystal alignment agent comprises a polymer (A), which is selected from one or more of the following groups: a tetracarboxylic acid derivative component containing at least one compound selected from the group consisting of tetracarboxylic acid dianhydrides and their derivatives, a diamine component, and an active ester compound (B) represented by formula (1). The polymer (A) also comprises a group from the aforementioned active ester compound (B) represented by formula (1A). The definitions of each symbol are as described in the instruction manual. The definitions of each symbol are as described in the instruction manual.

Description

Liquid crystal alignment agents, liquid crystal alignment films, liquid crystal display elements, compounds, and polymers This invention relates to liquid crystal alignment agents, liquid crystal alignment films, liquid crystal display elements, and compounds and polymers that can be used with them. Liquid crystal displays (LCDs) have historically been widely used as display units in personal computers, smartphones, mobile phones, and television receivers. An LCD typically includes: a liquid crystal layer sandwiched between a substrate and a color filter substrate; pixel electrodes and a common electrode that apply an electric field to the liquid crystal layer; an alignment film that controls the alignment of the liquid crystal molecules in the liquid crystal layer; and thin-film transistors (TFTs) that switch the electrical signals supplied to the pixel electrodes. Known methods for driving liquid crystal molecules include longitudinal electric field methods such as TN (twisted nematic) and VA (vertical alignment), and transverse electric field methods such as IPS (in-plane switching) and FFS (fringe field switching). The most widely used liquid crystal alignment film in industry today is produced by a process called triboelectric treatment, which involves rubbing the surface of a film formed on an electrode substrate, composed of polymers such as polyamide and / or polyimide that has been amide-modified, with a cloth such as cotton, nylon, or polyester in one direction. Triboelectric treatment is a simple and highly productive industrially useful method. However, with the increasing performance, precision, and size of liquid crystal display elements, various problems have become apparent, such as scratches, dust, mechanical stress, and static electricity on the surface of the alignment film caused by triboelectric treatment, leading to inhomogeneities within the alignment treatment surface. As an alternative to triboelectric treatment, photoalignment methods, which impart alignment capabilities to liquid crystals by irradiating them with polarized radiation, are known. Regarding photoalignment methods, methods utilizing photoisomerization reactions, photocrosslinking reactions, and photodecomposition reactions have been proposed (see, for example, Non-Patent Literature 1 and Patent Literature 1). For liquid crystal display elements using IPS and FFS driving methods that require high contrast, Patent Document 2 proposes a liquid crystal alignment agent containing a polyimide precursor or polyimide with a specific structure, suitable for liquid crystal display elements that can achieve good display characteristics even when using negative liquid crystals that improve contrast. [Prior Art Documents] [Patent Documents] [Patent Document 1] Japanese Patent Application Publication No. 9-297313 [Patent Document 2] WO2016 / 152928 [Non-Patent Document] [Non-Patent Literature 1] "Liquid Crystal Photoalignment Film", Kitowaki & Ichimura Functional Materials, November 1997, Vol. 17, No. 11, pp. 13-22 (The problem the invention aims to solve) In recent years, large-screen and high-resolution liquid crystal display (LCD) elements have become the mainstream, leading to higher requirements for their quality. Especially with the increasing size of LCD elements, variations in manufacturing processes can cause slight variations in the twist angle of the liquid crystal within the LCD element's surface. Such variations result in uneven brightness within the LCD element when displaying black, thus reducing the overall quality of the LCD. As stated above, the object of the present invention is to provide a liquid crystal alignment agent capable of obtaining a liquid crystal alignment film with small variation (non-uniformity) in the torsion angle of the liquid crystal within the liquid crystal alignment film surface, a liquid crystal alignment film obtained from the liquid crystal alignment agent, a liquid crystal display element using the liquid crystal alignment film, and compounds and polymers that can be used in these components. (Solution to the problem) In order to achieve the above-mentioned objectives, the inventors of this invention conducted extensive research and discovered that liquid crystal alignment agents containing polymers with specific compounds as constituent components are highly effective in achieving the above objectives, thus completing this invention. The present invention includes the following: A liquid crystal alignment agent comprising a polymer (A), wherein the polymer (A) is selected from one or more of the group consisting of a tetracarboxylic acid derivative component, a diamine component, and an active ester compound (B) represented by formula (1) obtained by reacting a polyimide precursor, a polyimide of a polyimide precursor, and a polyimide derivative thereof, and wherein the polymer (A) contains a group represented by formula (1A) from the active ester compound (B), [Chemical 1] In equation (1), W represents having one or more choices: *1-NH(Boc) and *1-N(Boc). 2. An organic group consisting of a protected amine group within the group formed by "*1-N(Boc)-*1)" (*1 representing an atomic bond to a carbon atom) and not a Boc group, having 1 to 30 carbon atoms, where Boc represents a tertiary butoxycarbonyl group. R represents an active ester-forming group; however, when R represents a group derived from N-hydroxysuccinimide, W has two or more of the aforementioned protected amine groups. [Chem. 2] W is synonymous with formula (1). * indicates an atomic bond to the polymer. (Effect of the invention) According to the present invention, a liquid crystal alignment agent that can obtain a liquid crystal alignment film with small variation (non-uniformity) of the torsion angle of liquid crystal within the liquid crystal alignment film surface, a liquid crystal alignment film obtained from the liquid crystal alignment agent, a liquid crystal display element using the liquid crystal alignment film, and compounds and polymers that can be used in them are provided. The mechanism by which the above-mentioned effects can be obtained according to the present invention is not necessarily clear, but it is believed that the following is one reason. The active ester compound (B) reacts with the polymer ends to obtain a highly hydrophobic polymer with protective amine groups introduced at the ends. If this is the case, when different types of polymers are mixed, the polymer with introduced protective amine groups tends to concentrate on the film surface, thus obtaining a liquid crystal alignment film with improved alignment uniformity. Furthermore, through the reaction of the active ester compound (B) with the polymer ends, the polymer ends are protected. As a result, it is believed that the decrease in polymer molecular weight caused by amide exchange during film calcination is suppressed, thus obtaining a liquid crystal alignment film with high alignment uniformity. The following provides a detailed description of a liquid crystal alignment agent containing a specific polymer, a liquid crystal alignment film formed using the liquid crystal alignment agent, and a liquid crystal display element having the liquid crystal alignment film. However, the following description of the constituent elements is merely an example of one embodiment of the present invention and is not intended to limit the scope of the invention. In the following description, "halogen atom" may include fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc. "Boc" represents a third butoxycarbonyl group, and "*" indicates a bond position. <Polymer (A)> The liquid crystal alignment agent of the present invention contains polymer (A) (hereinafter also referred to as polyimide-based polymer (A)). Polymer (A) is selected from one or more polyimides consisting of polyimide precursors and polyimides that are amides of the polyimide precursors. In polymer (A), the polyimide precursor is obtained by reacting a tetracarboxylic acid derivative component, a diamine component, and the above-mentioned active ester compound (B). The tetracarboxylic acid derivative component contains at least one compound selected from the group consisting of tetracarboxylic dianhydrides and their derivatives (hereinafter also collectively referred to as tetracarboxylic dianhydride compounds). Polymer (A) has a group represented by the above formula (1A) from the active ester compound (B). Examples of the above-mentioned polyimide precursors include polyamide and polyamide esters. Examples of the aforementioned tetracarboxylic dianhydride derivatives include tetracarboxylic acid dihalides, tetracarboxylic acid dialkyl esters, or tetracarboxylic acid dialkyl ester dihalides. Furthermore, independent of the liquid crystal alignment agent of this invention, the polymer (A) itself is also a subject of this invention. <<Polyimide Polymer (A)>> When the above-mentioned polyimide polymer (A) is polyamide, the polyimide polymer (A) can be obtained, for example, by polymerizing (condensing) a tetracarboxylic acid derivative containing tetracarboxylic dianhydride, a diamine component, and an active ester compound (B). Alternatively, the tetracarboxylic acid derivative containing tetracarboxylic dianhydride can be reacted with the diamine component to obtain a polymer solution containing unmodified polyamide, and then the active ester compound (B) can be added to the polymer solution to prepare the polyamide polymer (A). Furthermore, in the above-mentioned polyimide polymer (A), the polyimide is obtained by amide-imidizing the above-mentioned polyamide. Furthermore, when the aforementioned polyimide polymer (A) is a polyamide ester, it can be obtained by the method described later, by imidizing the polyamide ester to obtain polyimide. <<<Tetracarboxylic dianhydride compounds>>> The aforementioned tetracarboxylic dianhydride compounds include, for example, aromatic tetracarboxylic dianhydrides, acyclic aliphatic tetracarboxylic dianhydrides, or alicyclic tetracarboxylic dianhydrides, or derivatives thereof. Here, aromatic tetracarboxylic dianhydrides are acidic dianhydrides obtained by intramolecularly dehydrating four carboxyl groups, including at least one carboxyl group bonded to an aromatic ring. Acyclic aliphatic tetracarboxylic dianhydrides are acidic dianhydrides obtained by intramolecularly dehydrating four carboxyl groups bonded to a chain hydrocarbon structure. However, it is not necessary to consist solely of a chain hydrocarbon structure; a portion of it may also have an alicyclic or aromatic ring structure. Among the aforementioned aromatic tetracarboxylic dianhydrides or their derivatives, considering the viewpoint of improving liquid crystal alignment, it is preferable to have a tetracarboxylic dianhydride or its derivatives having at least one substructure selected from the group consisting of benzene ring structures, naphthalene ring structures, and aromatic heterocyclic structures. Furthermore, alicyclic tetracarboxylic dianhydrides are acidic dianhydrides obtained by intramolecularly dehydrating four carboxyl groups, including at least one carboxyl group bonded to an alicyclic structure. However, none of these four carboxyl groups are bonded to an aromatic ring. Also, it is not necessary for the structure to be solely alicyclic; a portion of it may also have a chain hydrocarbon structure or an aromatic ring structure. Among the aforementioned acyclic aliphatic or alicyclic tetracarboxylic dianhydrides, or their derivatives, considering the viewpoint of improving liquid crystal alignment, tetracarboxylic dianhydrides or their derivatives with at least one substructure selected from the group consisting of cyclobutane ring structures, cyclopentane ring structures, and cyclohexane ring structures are preferable. Among 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. [Chemistry 3] In equation (2), X represents the structure selected from the group consisting of the following equations (x-1)~(x-17) and the following equations (xr-1)~(xr-2). [Chemistry 4] [Chemistry 5] In equation (x-1), R 1 ~R 4 Each of these elements 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 alkoxy group having 2 to 6 carbon atoms, a fluorine-containing monovalent organogroup having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 6 carbon atoms, an alkoxycarbonyl group having 2 to 6 carbon atoms, or a phenyl group. In formula (x-7), R 5 and R 6 Each can independently represent a hydrogen atom or a methyl group. In formulas (xr-1)~(xr-2), j and k are integers of 0 or 1, and A 1 and A Each of the 2 groups independently represents a single bond, -O-, -CO-, -COO-, phenyl, sulfonyl, or amino group. Multiple A groups in formula (xr-2) 2 can be the same or different. *1 is an atomic bond bonded to one of the anhydride groups, *2 is an atomic bond bonded to the other anhydride group. An ideal concrete example of a tetracarboxylic acid dianhydride represented by the above formula (2) can be listed as X selected from the above formulas (x-1)~(x-8), (x-10)~(x-11), and (xr-1)~(xr-2). In the above equation (x-1), it is better to select an example from the group formed by the following equations (x1-1) to (x1-6). [Chemistry 6] *1 is an atomic bond bonded to one of the anhydride groups, and *2 is an atomic bond bonded to the other anhydride group. Ideal concrete examples of the above equations (xr-1) and (xr-2) can be listed as equations (xr-3) to (xr-18). [Chemistry 7] [Chemistry 8] In the above formula, * is a bond to the anhydride group. When manufacturing polyimide polymers (A), it is ideal for the amount of tetracarboxylic acid dianhydride or its derivatives represented by formula (2) above to be 5 mol% or more relative to 1 mol of all tetracarboxylic acid derivatives reacting with the diamine component, preferably 10 mol% or more, and even more than 20 mol% or more. <<<Active Ester Compound (B)>>> The polyimide polymer (A) of the present invention is obtained by using the active ester compound (B) represented by the above formula (1). By achieving this state, it is possible to impart a function of small variation (non-uniformity) in the torsion angle when manufacturing liquid crystal display elements. Furthermore, the active ester compound (B) itself is also the subject of the present invention, independent of the liquid crystal alignment agent of the present invention. In formula (1) above, R represents an active ester-forming group. Here, "active ester-forming group" refers to a chemical group that, together with the carbonyl group it is bonded to, forms an ester that activates the aforementioned carbonyl group through coupling reactions or other coupling reactions with an amino group-containing compound that forms an amino group. Examples of active ester-forming groups include hydroxyl compounds such as 1-hydroxybenzotriazole (HOBt), 1-hydroxy-7-azabenzotriazole (HOAt), N-hydroxysuccinimide (HOSu), ethyl 2-cyano-2-(hydroxyimino)acetate (oxyma), 3,4-dihydro-3-hydroxy-4-sideoxy-1,2,3-benzotriazole (HOOBt or HODhbt), N-hydroxy-5-norcamphene-2,3-dicarboxylated oxoimidide (HONB), 2,3,4,5,6-pentafluorophenol (HOPfp), or 6-chloro-1-hydroxy-1H-benzotriazole (Cl-HOBt) (see, for example, the catalogue of WATANABE Chemical, Amino acids and chiral building blocks to new medicine. These are also collectively referred to as hydroxyl compounds (Ae) below). These compounds have had the hydroxyl group removed. Among these, from the viewpoint of ideally obtaining the effects of the present invention, it is more ideal to remove the hydroxyl group from HOBt, HOAt, HOSu, or HOOBt, and even more ideal to remove the hydroxyl group from HOBt, HOAt, or HOOBt. Furthermore, when the active ester forming group is derived from a HOSu group, W has two or more of the aforementioned protective amine sites. Active esters derived from HOSu are considered to be less prone to reacting with the polymer terminus; therefore, in this case, by introducing two or more protective amine sites, sufficient effects can be obtained. In equation (1) above, W represents the option with more than one choice: *1-NH(Boc) or *1-N(Boc). 2. The group consisting of "*1-N(Boc)-*1)" (*1 represents an atomic bond bonded to a carbon atom.) is an organic group with a number of carbons of 1 to 30 that is not a Boc group. When there are two or more protective amine groups, each protective amine group may be the same or different. From the viewpoint of ideally obtaining the effect of the present invention, the number of protective amine groups should preferably be one or more, and from the viewpoint of the effect of liquid crystal alignment, the number of protective amine groups should preferably be four or less. The organic group in W that is not a Boc group with a number of carbons of 1 to 30 is preferably an organic group with a number of carbons of 1 to 12, and more preferably an organic group with a number of carbons of 1 to 6. Specifically, for W, a carboxyl group can be taken from the carboxyl group represented by "W-COOH" (W is synonymous with formula (1). It is also referred to as carboxylic acid (W) below.). The above-mentioned active ester compound (B) can be synthesized, for example, from carboxylic acid (W) and the above-mentioned hydroxyl compound (Ae). The above-mentioned carboxylic acid (W) has an intramolecular position that allows it to choose between *1-NH (Boc) and *1-N (Boc). 2. The group consisting of the group "*1-N(Boc)-*1)" (*1 represents an atomic bond with a carbon atom.) which contains the group protecting the amino group. The aforementioned carboxylic acid (W) can be obtained by protecting the amino groups of a carboxyl-containing polyamine (pA) having two or more amino groups, such as a monoamine (mA) or a diamine (pA). Furthermore, the protection of the amino groups can be limited to protecting only a portion of the amino groups of the amine, or it can be protecting all of the amino groups. Specific examples of monoamines (mA) include 1-carboxy-8-aminonaphthalene, 1-carboxy-7-aminonaphthalene, 1-carboxy-6-aminonaphthalene, 1-carboxy-5-aminonaphthalene, 1-carboxy-4-aminonaphthalene, 1-carboxy-3-aminonaphthalene, 1-carboxy-2-aminonaphthalene, 1-amino-7-carboxynaphthalene, 2-carboxy-7-aminonaphthalene, 2-carboxy-6-aminonaphthalene, 2-carboxy-5-aminonaphthalene, 2-carboxy-4-aminonaphthalene, etc. Aromatic monoamines such as aminonaphthalene, 2-carboxy-3-aminonaphthalene, 1-amino-2-carboxynaphthalene, 2-aminonicotinic acid, 4-aminonicotinic acid, 5-aminonicotinic acid, 6-aminonicotinic acid, 3-amino-o-tolycylaminoic acid, 2-aminobenzoic acid, 3-aminobenzoic acid, or 4-aminobenzoic acid; and aliphatic monoamines such as glycine, alanine, methionine, isoleucine, leucine, phenylalanine, or proline. Specific examples of polyamines (pA) include diaminobenzoic acids such as 3,5-diaminobenzoic acid; carboxybiphenyl compounds such as 4,4'-diaminobiphenyl-3-carboxylic acid; carboxydiphenylalkanes such as 4,4'-diaminodiphenylmethane-3-carboxylic acid or 4,4'-diaminodiphenylethane-3-carboxylic acid; aromatic polyamines represented by carboxydiphenyl ethers such as 4,4'-diaminodiphenyl ether-3-carboxylic acid or 4,4'-diaminodiphenyl ether-3-carboxylic acid; and aliphatic polyamines such as arginine, lysine, ornithine, or histidine. From the viewpoint of ideally achieving the effects of the present invention, it is preferable that the aforementioned carboxylic acid (W), monoamine (mA), and polyamine (pA) contain a nitrogen-containing heterocycle or its derivatives. Specific examples of such nitrogen-containing heterocycles include aziridine, acridine, pyrrole, imidazole, imidazoline idine, pyrrolidine, piperidine, piperazine, pyridine, indole, benzimidazole, or carbazole. Furthermore, specific examples of derivatives of nitrogen-containing heterocycles include compounds formed by substituting any hydrogen atom of the nitrogen-containing heterocycle with a substituent. Examples of such substituents include: linear or branched alkyl groups having 1 to 4 carbon atoms, linear or branched alkoxy groups having 1 to 4 carbon atoms, hydroxyl groups, halogen atoms, nitro groups, cyano groups, trifluoromethyl groups, and -NR groups. 7R 8. or -CONR 7R 8 bases, R 7 and R 8. Each of these can be independently represented as a hydrogen atom or an alkyl group with 1 to 4 carbon atoms in a straight or branched chain. The active ester compound represented by formula (1) above is preferably any one of the compounds represented by formulas (b-1) to (b-7) below. [Chemistry 9] When manufacturing polyimide polymers (A), the ideal proportion of active ester compound (B) relative to the total 100 moles of diamine components used is 0.01 to 50 moles, and even more ideal is 0.1 to 30 moles. <<<Diamine Component>>> The diamine component used in the manufacture of polyimide precursors is not particularly limited, but it is preferable to use a diamine component containing the diamine represented by formula (3) below. [Chemical 10] In equation (3), Ar 1 and Ar 1’ Each can independently represent a benzene ring, a biphenyl structure, or a naphthalene ring, and one or more hydrogen atoms on the benzene ring, the biphenyl structure, or the naphthalene ring can be substituted with a monovalent group. L 1 and L 1’Each can independently represent a single bond, -O-, -C(=O)-, -C(=O)-O-, or -OC(=O)-. A represents -CH. 2- A divalent organoalkyl group consisting of an alkyl group having 2 to 12 carbon atoms, or an alkyl group having at least one of the groups -O-, -C(=O)-O-, and -OC(=O)- inserted between the carbon-carbon bonds of the alkyl group. Any hydrogen atom possessed by A may also be replaced by a halogen atom. Ar in equation (3) above 1 and Ar 1’ Each can independently represent a benzene ring, a biphenyl structure, or a naphthalene ring. One or more hydrogen atoms on the benzene ring, the biphenyl structure, or the naphthalene ring may also be replaced by a monovalent group, which may include halogen atoms, alkyl groups with 1 to 3 carbon atoms, alkenyl groups with 2 to 3 carbon atoms, alkoxy groups with 1 to 3 carbon atoms, fluoroalkyl groups with 1 to 3 carbon atoms, fluoroalkenyl groups with 2 to 3 carbon atoms, fluoroalkoxy groups with 1 to 3 carbon atoms, alkoxycarbonyl groups with 2 to 3 carbon atoms, cyano groups, nitro groups, etc. Ar in equation (3) above 1 and Ar 1’ In, the amino group and L 1 or L 1’ The bonding position relative to the benzene ring is preferably 1,4- or 1,3-position, with 1,4-position being more preferred. The amino group and L... 1 or L 1’ For the biphenyl structure, the 4,4'- or 3,3'-position is more ideal, with the 4,4'-position being the best. The amino group and L... 1 or L 1’ The bonding positions relative to the naphthalene ring are ideally 1,5- or 2,6-positions, with 2,6-position being the best. Ar 1 and Ar 1’ Ideal examples include benzene rings, biphenyl structures, and naphthalene rings. In equation (3) above, A represents -CH 2- or a divalent organoalkyl group consisting of an alkyl group having 2 to 12 carbon atoms, or an alkyl group having at least one of the groups -O-, -C(=O)-, and -OC(=O)- inserted between the carbon-carbon bonds of the alkyl group. Any hydrogen atom in A may be replaced by a halogen atom. The alkyl group having 2 to 12 carbon atoms can be linear or branched, but linear is preferred. The -O-, -C(=O)-, and -OC(=O)- inserted into the divalent organoalkyl group can be one or more. An ideal specific example of A is a linear alkyl group having 2 to 6 carbon atoms. In the above formula (3), the base -L 1-AL 1’ Ideal examples can be listed below. -(CH) 2) n -、 -O-(CH 2) n -、 -O-(CH 2) n -O-、 -C(=O)-(CH 2) n -C(=O)-、 -OC(=O)-(CH 2) n -O-、 -OC(=O)-(CH 2) n -OC(=O)-、 -OC(=O)-(CH 2) n -C(=O)-O-、 -C(=O)-O-(CH 2) n -OC(=O)-、 -(CH 2) m1 -O-(CH 2) n’ -O-(CH 2) m2 -、 -(CH 2) m1 -OC(=O)-(CH 2) n’ -C(=O)-O-(CH 2) m2 -、 -(CH 2) m1 -C(=O)-O-(CH 2) n’-OC(=O)-(CH 2) m2 - The above-based-L 1-AL 1’ In the ideal specific example, n is an integer from 1 to 12, preferably an integer from 2 to 12, and even more preferably an integer from 2 to 6. The sum of m1, m2, and n' is an integer from 3 to 12, preferably an integer from 6 to 12. It is ideal for m1 and m2 to each be integers from 1 to 4, and even more ideal for them to be integers from 2 to 4. It is ideal for n' to be an integer from 1 to 6, even more ideal for it to be an integer from 2 to 6, and even more ideal for it to be an integer from 2 to 4. The proportion of diamine expressed in formula (3) is preferably 1 mol% or more relative to 1 mol of diamine content, more preferably 10 mol% or more, and more preferably 20 mol% or more. Polyimide polymers (A) may also contain diamines other than those described above. Examples of other diamines are listed below, but the invention is not limited to these. When using diamines other than those represented by formula (3), it is preferable that the amount of diamine represented by formula (3) relative to the diamine component is 90 mol% or less, and more preferably 80 mol% or less. Examples of other diamines are listed below, but the invention is not limited to these. The aforementioned other diamines may be used alone or in combination of two or more. 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, and semi-aromatic diamines having a secondary and a primary amino group (preferably 4-(2-(methylamino)ethyl)aniline). (Here, a semi-aromatic diamine refers to one amino group bonded to an aromatic ring, and the other amino group...) Diamines not bonded to an aromatic ring. Examples include 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, 3-trifluoromethyl-4,4'-diaminobiphenyl, 2-trifluoromethyl-4,4'-diaminobiphenyl, 3-fluoro-4,4'-diaminobiphenyl, and 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-Diamine Diamines with a tetracarboxylic acid diimide structure include 2,6-diaminonaphthalene, 2,7-diaminonaphthalene, 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. 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'-Diphenyl Aminoazobenzene, 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) [4,4,4-trifluorobutoxy]benzoate, represented by aromatic diamines with cinnamic acid ester structures, and other photooriented diamines; 2-(2,4-diaminophenoxy)ethyl methacrylate or 2,4-diamino-N,N-diallyl aniline, etc., which have photopolymerization at the end. Diamines with a radical group; diamines that act as free radical polymerization initiators, such as 1-(4-(2-(2,4-diaminophenoxy)ethoxy)phenyl)-2-hydroxy-2-methylpropanone and 2-(4-(2-hydroxy-2-methylpropionic)phenoxy)ethyl 3,5-diaminobenzoate; diamines with an amide bond, such as 4,4'-diaminobenzonitrile; diamines with a urea bond, such as 1,3-bis(4-aminophenyl)urea; H 2N-Y D -NH 2(Y D This indicates diamines with thermally detachable groups, such as those containing a divalent organic group (-N(D)-, where D represents a protecting group that is removed and replaced by a hydrogen atom upon heating). 3,3'-Diaminodiphenyl ether, 3,4'-Diaminodiphenyl ether, 4,4'-Diaminodiphenyl ether, 4,4'-Sulfodiphenylamine, 3,3'-Sulfodiphenylamine, bis(4-aminophenyl)silane, bis(3-aminophenyl)silane, dimethyl-bis(4-aminophenyl)silane, dimethyl-bis(3-aminophenyl)silane, 4,4'-thiodiphenyl ether Aniline, 3,3'-thiodiphenylamine, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(4-aminophenoxy)diphenyl ether, 1,4-bis[4-(4-aminophenoxy)phenoxy]benzene, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 4,4'-diaminodiphenyl ketone, 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-aminoazolyl]-aniline, 4-[4-[(4-aminophenoxy)methyl]-4,5-diaminobenzamide [H-2-Azolyl]-aniline, 1,4-bis(p-aminobenzyl)piperidine, 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-di) 1,4-Bis-(4-aminophenyl)-piperazine, 2-N-(4-aminophenyl)pyridine-2,5-diamine, 2-N-(5-aminopyridine-2-yl)pyridine-2,5-diamine, 2-(4-aminophenyl)-5-aminobenzimidazole, 2-(4-aminophenyl)-6-aminobenzimidazole, 5-(1H-benzimidazole) Diamines containing a heterocyclic structure, such as 2-yl)phenyl-1,3-diamine, or diamines represented by formulas (z-1) to (z-5), or diamines with a diphenylamine structure such as 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-phenylenediamine, are represented by diamines having a diphenylamine structure, which have at least one nitrogen-containing structure selected from the group consisting of a heterocycle containing a nitrogen atom, a secondary or tertiary amino group (excluding diamines from the amino group derived from -N(D)- (D represents a protecting group that is removed and replaced by a hydrogen atom by heating). 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, 4,4'-Diaminobiphenyl-3,3 Diamines containing carboxyl groups, such as '-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-dihydroindene-5-amine, 1-( Diamines having a steroid skeleton, such as (4-aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H-inden-6-amine; diamines represented by formulas (V-1) to (V-2); Diamines containing siloxane bonds, such as 1,3-bis(3-aminopropyl)-tetramethyldisiloxane; noncyclic aliphatic diamines such as m-xylene diamine, 1,3-propane diamine, tetramethylene diamine, pentamethylene diamine, and hexamethylene diamine; alicyclic diamines such as 1,3-bis(aminomethyl)cyclohexane, 1,4-diaminocyclohexane, and 4,4'-methylenebis(cyclohexylamine); and diamines with two amino groups bonded by any of the formulas (Y-1) to (Y-167) described in WO2018 / 117239. [Chemistry 11] [Chemistry 12] In equation (V-1), m and n are integers from 0 to 3 (but satisfying 1 ≤ m + n ≤ 4), j is an integer of 0 or 1, and X 1 Indicates -(CH) 2) a -(a is an integer from 1 to 15.), -CONH-, -NHCO-, -CO-N(CH 3) -, -NH-, -O-, -CH 2O-、-CH 2-OCO-, -COO-, or -OCO-. R 1 This represents a fluorine atom, an alkyl group containing fluorine atoms having 1 to 10 carbon atoms, an alkoxy group containing fluorine atoms having 1 to 10 carbon atoms, an alkyl group having 3 to 10 carbon atoms, an alkoxy group having 3 to 10 carbon atoms, or an alkoxyalkyl group having 3 to 10 carbon atoms. In formula (V-2), X 2 Indicates -O-, -CH 2O-、-CH 2-OCO-, -COO-, or -OCO-, R 2 Indicates alkyl groups with 3 to 30 carbon atoms, or alkyl groups with 3 to 20 carbon atoms containing fluorine atoms. m, n, X 1 and R 1 When there are two, each has the above definition independently. Furthermore, the D in the -N(D)- group of the other diamines mentioned above should ideally be a carbamate ester protecting group represented by benzyloxycarbonyl, 9-furoylmethoxycarbonyl, allyloxycarbonyl, Boc, etc. Considering the good efficiency of heat-based desorption, the ability to desorb at relatively low temperatures, and the release of harmless gases during desorption, Boc is preferred. Ideal examples of diamines with thermally detachable groups, as exemplified by the other diamines mentioned above, can be listed as diamines selected from formulas (d-1) to (d-7). [Chemistry 13] In formulas (d-2), (d-6), and (d-7), R represents a hydrogen atom or Boc. Regarding the diamine component used in the manufacture of polyimide precursors, when using the aforementioned diamine with thermally detachable groups, from the viewpoint of ideally obtaining the effects of the present invention, it is preferable to use 5 to 40 mol% of the diamine component relative to 1 mol, 5 to 35 mol% is more preferable, and 5 to 30 mol% is even more preferable. The liquid crystal alignment agent of the present invention may also contain polymers other than polymer (A). Specific examples of other polymers include polymers (Q) selected from the group consisting of at least one of polyimide precursors obtained by using tetracarboxylic acid derivatives and diamines, and polyimides of polyimide precursors, 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, without using the active ester compound (B) represented by formula (1) above as a raw material; 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) derivatives, and poly(meth)acrylates. Regarding the aforementioned polymer (Q), considering the viewpoint of improving voltage retention rate, polymers selected from at least one group consisting of a polyimide precursor obtained by using a diamine component containing a diamine with a nitrogen-containing structure and a amide of the polyimide precursor (hereinafter also referred to as polyimide polymers (Q)) can be listed. Specific examples of poly(styrene-maleic anhydride) copolymers include SMA1000, SMA2000, SMA3000 (manufactured by Cray Valley), GSM301 (manufactured by GIFUSHELLAC), etc.; specific examples of poly(isobutylene-maleic anhydride) copolymers include ISOBAM-600 (manufactured by Kuraray); and specific examples of poly(vinyl ether-maleic anhydride) copolymers include Gantrez AN-139 (methyl vinyl ether maleic anhydride resin, manufactured by ASHLAND). Other polymers may be used alone or in combination of two or more. Ideally, the proportion of other polymers should be 10-90 parts by mass, and more ideally 20-80 parts by mass, relative to 100 parts by mass of the polymer component in the liquid crystal alignment agent. Furthermore, in this specification, "polymer component" refers to polymer (A) contained in the liquid crystal alignment agent and all other polymers besides polymer (A). When the liquid crystal alignment agent contains only polymer (A), the polymer component refers to polymer (A). The tetracarboxylic acid derivative component used to obtain the above-mentioned polyimide polymer (Q) may, for example, contain a tetracarboxylic acid dianhydride derivative component of the tetracarboxylic acid dianhydride compound exemplified in the above-mentioned polyimide polymer (A). Among the tetracarboxylic acid dianhydride compounds used to obtain the polyimide polymer (Q), the tetracarboxylic acid dianhydride or its derivative represented by formula (2) above is preferred. The amount of the tetracarboxylic acid dianhydride or its derivative represented by formula (2) above used is preferably 10 mol% or more, and more preferably 20 mol% or more, relative to 1 mol of all tetracarboxylic acid derivative components reacting with the diamine component. <Method for Manufacturing Polyimide Precursors> Polyamide, one of the polyimide precursors, can be manufactured by the following method. Specifically, a tetracarboxylic acid derivative containing tetracarboxylic acid dianhydride and the aforementioned diamine component can be reacted in the presence of an organic solvent, preferably at -20 to 150°C, more preferably at 0 to 50°C, preferably for 30 minutes to 24 hours, and more preferably for 1 to 12 hours (condensation reaction) to synthesize the product. Specific examples of organic solvents used in the above reaction include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, and 1,3-dimethyl-2-imidazolidineone. Furthermore, when 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 can be used. Two or more of these can also be mixed. The reaction can be carried out at any concentration, preferably 1-50% by mass, more preferably 5-30% by mass. The reaction is initially carried out at a high concentration, and solvent may be added subsequently. 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 0.8-1.2. Similar to typical polycondensation reactions, the closer this mole ratio is to 1.0, the larger the molecular weight of the resulting polyamide becomes. The polyacrylic acid obtained from the above reaction can be precipitated and recovered by continuously stirring the reaction solution while injecting it into a poor solvent. After several precipitation cycles, washing with the poor solvent, and drying at room temperature or by heating, refined polyacrylic acid powder can be obtained. The poor solvent is not particularly limited and examples include water, methanol, ethanol, hexane, butylcerox, acetone, and toluene. Polyamide esters, which are one of the precursors of polyimide, can be manufactured by known methods such as (1) esterifying the above-mentioned polyamide, (2) reacting a tetracarboxylic acid derivative component containing a tetracarboxylic acid diester dichloride with a diamine component, and (3) polycondensing a tetracarboxylic acid derivative component containing a tetracarboxylic acid diester with a diamine. When manufacturing the aforementioned polyamides and polyamide esters, end-modified polymers can be obtained by using the aforementioned tetracarboxylic acid derivative components and diamine components, and by using appropriate end-capping agents. End-capping agents include, for example, acetic anhydride, maleic anhydride, nalidixic anhydride, phthalic anhydride, itaconic 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 diester compounds such as ditert-butyl dicarbonate and diallyl dicarbonate; chlorocarbonyl compounds such as acrylonitrile chloride, methacrylic chloride, and nicotinic chloride; benzene... Monoamine compounds such as amines, 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 capping agent used relative to 100 moles of the total diamine components is preferably 40 moles or less, and more preferably 30 moles or less. Furthermore, the proportion of the capping agent used is preferably 0.01 mol or more relative to 100 mol of the total diamine component used, and even more preferably 0.1 mol or more. <Method for Manufacturing Polyimide> The polyimide used in this invention can be manufactured by amide-imidizing the aforementioned polyimide precursor using known methods. In the polyimide, the ring-closure rate (also known as the amide ratio) of the functional groups possessed by the polyamide acid or polyamide ester is not necessarily 100%, and can be adjusted arbitrarily according to the application and purpose. In the polymer (A) of this invention, the amide ratio of the polyimide can be, for example, 20-100%, 50-99%, or 70-99%, considering the viewpoint of reducing the incidence of display defects. Methods for obtaining polyimide by amide oxidation of the above-mentioned polyamide or polyamide ester include thermal amide oxidation by directly heating the solution of the above-mentioned polyamide or polyamide ester, and catalytic amide oxidation by adding a catalyst (e.g., alkaline catalysts such as pyridine, acid anhydrides such as acetic anhydride) to the solution of the above-mentioned polyamide or polyamide ester. <Polymer Solution Viscosity and Molecular Weight> The polyamides, polyamide esters, and polyimides used in this invention are ideal from a workability point of view when prepared into solutions with a concentration of 10-15% by mass, for example, having a solution viscosity of 10-1000 mPa·s, but there are no particular limitations. Furthermore, the aforementioned polymer solution viscosity (mPa·s) is the value measured at 25°C using an E-type rotational viscometer for a 10-15% by mass polymer solution prepared using a good solvent for that polymer (e.g., γ-butyrolactone, N-methyl-2-pyrrolidone, etc.). The weight-average molecular weight (Mw) of the polystyrene, as measured by gel permeation chromatography (GPC) of the aforementioned polyamides, polyamide esters, and polyimides, is preferably 1,000 to 500,000, 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 measured by GPC, is preferably 15 or less, more preferably 10 or less. This molecular weight range ensures good liquid crystal alignment of the liquid crystal display element. <Liquid Crystal Alignment Agent> The liquid crystal alignment agent of this invention is used to prepare a liquid crystal alignment film. Considering the formation of a uniform thin film, it is adopted in the form of a coating liquid. The liquid crystal alignment agent of this invention is preferably a coating liquid containing the aforementioned polymer components and solvent. The content (concentration) of the polymer components in the liquid crystal alignment agent of this invention can be appropriately varied according to the desired coating thickness. Considering the formation of a uniform and defect-free coating, it is ideally 1% by mass or more relative to the total amount of the liquid crystal alignment agent. Considering the storage stability of the solution, it is preferably 10% by mass or less. The proportion of polymer (A) in the liquid crystal alignment agent, considering the ideal effect of this disclosure, 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 polymer contained in the liquid crystal alignment agent. When a liquid crystal alignment agent contains other polymers, the ideal proportion of polymer (A) relative to 100 parts by mass of the polymer component in the liquid crystal alignment agent is 10 to 90 parts by mass, and even more ideal is 20 to 80 parts by mass. The solvent contained in liquid crystal alignment agents is not particularly limited as long as the polymer components can be uniformly dissolved. 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-imidazolidineone, 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-(3-methoxypropyl)-2-pyrrolidone, N-(2-ethoxyethyl)-2-pyrrolidone, N-(4-methoxybutyl)-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone (these can also be collectively referred to as "good solvents"), etc. Among them, 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 20-99% by mass of the total solvent contained in the liquid crystal alignment agent, 20-90% by mass is even better, and 30-80% by mass is particularly ideal. Furthermore, the solvent contained in the liquid crystal alignment agent should preferably be a mixture of the aforementioned solvents and a solvent that improves the coatability and surface smoothness of the coating film when applying the liquid crystal alignment agent (also known as a poor solvent). Specific examples of the poor solvents used are listed below, but are not limited to these. Examples include: diisopropyl ether, diisobutyl ether, diisobutylmethanol (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 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 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, isoamyl lactate, diethylene glycol monoethyl ether, diisobutyl ketone (2,6-dimethyl-4-heptanone), etc. The ideal content of undesirable solvent is 1-80% by mass of the total solvent contained in the liquid crystal alignment agent, 10-80% by mass is better, and 20-70% by mass is even better. 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. Among them, 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 are preferred. An ideal combination of good and bad solvents can be listed as follows: N-methyl-2-pyrrolidone with ethylene glycol monobutyl ether; N-methyl-2-pyrrolidone with γ-butyrolactone and ethylene glycol monobutyl ether; N-methyl-2-pyrrolidone with γ-butyrolactone and propylene glycol monobutyl ether; N-ethyl-2-pyrrolidone with propylene glycol monobutyl ether; N-methyl-2-pyrrolidone with γ-butyrolactone and 4-hydroxy-4-methyl-2-pentanone with 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 diisobutyl methanol, 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. The liquid crystal alignment agent of the present invention may also contain additional components other than polymer components and solvents (hereinafter also referred to as additive components). Such additive components include compounds for improving the strength of the liquid crystal alignment film (hereinafter also referred to as crosslinking compounds), adhesion promoters for improving the adhesion between the liquid crystal alignment film and the substrate, and the adhesion between the liquid crystal alignment film and the sealant, dielectrics and conductive materials for adjusting the dielectric constant and resistance of the liquid crystal alignment film, etc. The aforementioned crosslinking compounds are, for example, crosslinking compounds selected from the group consisting of at least one substituent selected from epoxy, propylene oxide, acezoline, cyclic carbonate, terminal isocyanate, hydroxyl, and alkoxy groups (c-1) and crosslinking compounds having polymerizable unsaturated groups (c-2). Ideal specific examples of the aforementioned crosslinking compounds (c-1) and (c-2) are listed below. 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, dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetracyclooxypropyl-2,4-hexanediol, bisphenol A type epoxy resins such as EPIKOTE 828 (manufactured by Mitsubishi Chemical Corporation), bisphenol F type epoxy resins such as EPIKOTE 807 (manufactured by Mitsubishi Chemical Corporation), hydrogenated bisphenol A type epoxy resins such as YX-8000 (manufactured by Mitsubishi Chemical Corporation), and YX6954BH30 (manufactured by Mitsubishi Chemical Corporation), etc. Compounds containing a biphenyl skeleton, such as phenolic varnish epoxy resins like EPPN-201 (manufactured by Nippon Kayaku Co., Ltd.), (ortho-, meta-, and para-)cresol varnish epoxy resins like EOCN-102S (manufactured by Nippon Kayaku Co., Ltd.), tetra(epoxypropoxymethyl)methane, N,N,N',N'-tetracyclooxypropyl-1,4-phenylenediamine, N,N,N',N'-tetracyclooxypropyl-2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2-bis[4-(N,N-dicyclooxypropyl-4-aminophenoxy)phenyl]propane, and N,N,N',N'-tetracyclooxypropyl-4,4'-diaminodiphenylmethane, are compounds in which tertiary nitrogen atoms and aromatic carbon atoms are bonded together.N,N,N',N'-Tetracyclooxypropyl-1,2-diaminocyclohexane, N,N,N',N'-Tetracyclooxypropyl-1,3-diaminocyclohexane, N,N,N',N'-Tetracyclooxypropyl-1,4-diaminocyclohexane, bis(N,N-dicyclooxypropyl-4-aminocyclohexyl)methane, bis(N,N-dicyclooxypropyl-2-methyl-4-aminocyclohexyl)methane, bis(N,N-dicyclooxypropyl-3-methyl-4-aminocyclohexyl)methane, 1,3-bis(N,N-dicyclooxypropylaminomethyl)cyclohexane, 1,4-bis(N,N-dicyclooxypropylaminomethyl)cyclohexane Compounds of tertiary nitrogen atom and aliphatic carbon atom bonded together, such as hexane, 1,3-bis(N,N-dicyclooxypropylaminomethyl)benzene, 1,4-bis(N,N-dicyclooxypropylaminomethyl)benzene, 1,3,5-tris(N,N-dicyclooxypropylaminomethyl)cyclohexane, 1,3,5-tris(N,N-dicyclooxypropylaminomethyl)benzene; isocyanurate compounds such as tricyclooxypropyl isocyanate produced by Nissan Chemical Co., Ltd.; compounds described in paragraph

[0037] of Japanese Patent Application Publication No. 10-338880; and compounds described in WO2017 / 170483. Compounds containing propylene oxide, 1,4-bis{[(3-ethyl-3-epoxypropane)methoxy]methyl}benzene (ARON OXETANEOXT-121(XDO)), bis[2-(3-epoxypropane)butyl] ether (ARON OXETANEOXT-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 containing two or more propylene oxide groups as described in paragraphs

[0170] to

[0175] of WO2011 / 132751, etc. Compounds having an acezoline structure include, for example, compounds such as 2,2'-bis(2-acezoline) and 2,2'-bis(4-methyl-2-acezoline), polymers and oligomers of EPOCROS (trade name, manufactured by Nippon Shokubai Co., Ltd.) with an acezoline group, and compounds described in paragraph

[0115] of Japanese Patent Application Publication No. 2007-286597; Compounds having a cyclic carbonate group include 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, and compounds described in paragraphs

[0025] to

[0030] and

[0032] of WO2011 / 155577.Compounds having capped isocyanate groups include CORONATEAP STABLE M, CORONATE2503, 2515, 2507, 2513, 2555, MILLIONATEMS-50 (all manufactured by Tosoh Corporation), TAKENATEB-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 Japanese Patent Application Publication No. WO2015 / 141598, etc. 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, Japanese Patent Application Publication No. 2016-118753, Japanese Patent Application Publication No. 2016-200798, and compounds described in Japanese Patent Application Publication No. WO2010 / 074269, etc. Crosslinkable compounds with polymerizable unsaturated groups include glycerol mono(meth)acrylate, glycerol di(meth)acrylate (a mixture of 1,2- and 1,3-dimethyl acrylates), glycerol tri(meth)acrylate, glycerol 1,3-diglyceric acid di(meth)acrylate, neopentyltetrol 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. The above-mentioned compounds are examples of cross-linking compounds, but are not limited to these. For example, the components other than those mentioned above disclosed on pages 53

[0105] to 55

[0116] of WO2015 / 060357. Furthermore, cross-linking compounds may also combine two or more types. When using crosslinking compounds, the content of crosslinking compounds in the liquid crystal alignment agent is preferably 0.5 to 20 parts by mass relative to 100 parts by mass of polymer components contained in the liquid crystal alignment agent, and more preferably 1 to 15 parts by mass. The aforementioned sealing aids include, for example, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-ureopropyltrimethoxysilane, 3-ureopropyltriethoxysilane, and N-ethoxycarbonyl-3-aminopropyltrimethoxysilane. Silane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-3-triethoxysilylpropyltriethyleneethyltetramine, N-3-trimethoxysilylpropyltriethyleneethyltetramine, 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, N-Benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-epoxypropoxypropylmethyldimethoxysilane, 3-epoxypropoxypropyltrimethoxysilane, 3-epoxypropoxypropylmethyldiethoxysilane, 3-epoxypropoxypropyltriethoxysilane, p-styrene Silane coupling agents such as trimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, tris(3-(trimethoxysilyl)propyl)isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-isocyanatepropyltriethoxysilane. When using a binding aid, the content of the binding aid 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. Dielectric or conductive materials, such as monoamines containing nitrogen-containing aromatic heterocycles, such as 3-pyridinemethylamine. When using dielectric or conductive materials, the content of dielectric or conductive materials in the liquid crystal alignment agent is preferably 0.1 to 30 parts by weight relative to 100 parts by weight of polymer components contained in the liquid crystal alignment agent, and more preferably 0.1 to 20 parts by weight. (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, the steps of coating the liquid crystal alignment agent onto a substrate, calcining, and irradiating the obtained film with polarized radiation. An ideal form of the manufacturing method of the liquid crystal alignment film of the present invention includes, for example, the steps of coating the liquid crystal alignment agent onto a substrate (step (1)), calcining the coated liquid crystal alignment agent (step (2)), and, depending on the situation, performing alignment treatment on the film obtained in step (2) (step (3)). <Step (1)> The substrate for coating the liquid crystal alignment agent used in this invention is not particularly limited as long as it is a highly transparent substrate, and can also be a glass substrate, silicon nitride substrate, acrylic substrate, polycarbonate substrate, or other plastic substrate. In this case, it is more ideal from the viewpoint of simplifying the process if a substrate with ITO (Indium Tin Oxide) electrodes for driving the liquid crystal is used. Furthermore, for reflective liquid crystal display elements, if it is only a single-sided substrate, an opaque material such as a silicon wafer can also be used, and the electrodes in this case can also be made of light-reflecting materials such as aluminum. Methods for coating liquid crystal alignment agents onto a substrate and forming a film include screen printing, offset printing, flexographic printing, inkjet printing, and spraying. Among these, inkjet printing is considered the most ideal method for coating and forming a film. <Step (2)> Step (2) is the step of calcining the liquid crystal alignment agent coated on the substrate to form a film. After the liquid crystal alignment agent is coated on the substrate, the solvent can be evaporated or the amide or amide ester in the polymer can be thermally amided by heating means such as a hot plate, a thermal cycling oven or an IR (infrared) oven. The drying and calcining steps after coating the liquid crystal alignment agent of the present invention can be performed at any temperature and time, and can be performed multiple times. The temperature at which the solvent of the liquid crystal alignment agent evaporates can be, for example, 40~180°C depending on the temperature of the heating means, and can also be performed at 40~150°C from the point of view of shortening the processing time. The calcination time is not particularly limited, for example, 1~10 minutes, preferably 1~5 minutes. When performing a thermal amide formation step of the amide acid or amide ester in the polymer, in addition to the solvent evaporation step, a calcination step can be performed at a temperature of 150-300°C, preferably 150-250°C, after the solvent evaporation step. The calcination time for the thermal amide formation step is not particularly limited, for example, 5-40 minutes, preferably 5-30 minutes. If the film after calcination is too thin, the reliability of the liquid crystal display element may sometimes be reduced; 5-300 nm is ideal, and 10-200 nm is even more ideal. <Step (3)> Step (3) is a step of aligning the film obtained in step (2) as appropriate. That is, in vertical alignment type liquid crystal display elements such as VA type or PSA (Polymer Sustained Alignment) type, the formed coating film can be used directly as a liquid crystal alignment film, but alignment capability can also be imparted to the coating film. The alignment processing method for liquid crystal alignment film can be the rubbing method, but the photoalignment method is more ideal. The photoalignment method can include irradiating the surface of the above film with radiation that is polarized in a certain direction, and then heating it as appropriate to impart liquid crystal alignment property (also known as liquid crystal alignment capability). The radiation can be ultraviolet light or visible light with a wavelength of 100~800nm. Among them, ultraviolet light with a wavelength of 100~400nm is preferred, and more preferably ultraviolet light with a wavelength of 200~400nm. The radiation dose mentioned above is 1~10,000 mJ / cm². 2 Ideally, 100~5,000 mJ / cm 2 Even more ideally, during irradiation, to improve the alignment of the liquid crystal, the substrate having the above-mentioned film can be heated at 50~250°C while being irradiated. The liquid crystal alignment film prepared in this manner can stably align the liquid crystal molecules in a specific direction. Furthermore, the liquid crystal alignment film irradiated with polarized radiation using the above method can be contacted with a solvent, or the irradiated liquid crystal alignment film can be heat-treated. There are no particular restrictions on the solvents used in the above-mentioned contact treatment if they can dissolve the decomposition products generated from the film due to radiation irradiation. Specific examples include water, methanol, ethanol, 2-propanol, acetone, methyl ethyl ketone, 1-methoxy-2-propanol, 1-methoxy-2-propanol acetate, butyl ceroxysulfate, ethyl lactate, methyl lactate, diacetone alcohol, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propyl acetate, butyl acetate, and cyclohexyl acetate. Among these, considering versatility and solvent safety, water, 2-propanol, 1-methoxy-2-propanol, or ethyl lactate are preferred. Water, 1-methoxy-2-propanol, or ethyl lactate are more preferred. One solvent or a combination of two or more solvents can be used. The aforementioned contact treatments include immersion treatment and spray treatment (also known as spraying treatment). Considering the efficient dissolution of decomposition products generated from the film due to radiation irradiation, the treatment time for these treatments is preferably 10 seconds to 1 hour. Immersion treatment for 1 minute to 30 minutes is even better. Furthermore, the solvent used in the above contact treatments can be at room temperature or heated, preferably 10 to 80°C, with 20 to 50°C being more ideal. In addition, considering the solubility of the decomposition products, ultrasonic treatment may be performed as needed. After the above contact treatment, rinsing (also known as washing) and calcination using low-boiling-point solvents such as water, methanol, ethanol, 2-propanol, acetone, and methyl ethyl ketone are preferable. At this time, either washing or calcination, or both, can be performed. The calcination temperature is preferably 150–300°C, more preferably 180–250°C, and ideally 200–230°C. Furthermore, the calcination time is ideally 10 seconds to 30 minutes, and even more preferably 1 minute to 10 minutes. For the heat treatment of the coating irradiated by the above radiation, 50–300°C for 1 minute to 30 minutes is preferable, and 120–250°C for 1 minute to 30 minutes is even better. (Liquid Crystal Display Element) The liquid crystal display element of the present invention includes the liquid crystal alignment film of the present invention. Considering the need for high liquid crystal alignment, the liquid crystal alignment film of the present invention is suitable as a liquid crystal alignment film for transverse electric field liquid crystal display elements such as IPS and FFS types, and is particularly useful as a liquid crystal alignment film for FFS type liquid crystal display elements. The liquid crystal display element can be manufactured by obtaining a substrate with a liquid crystal alignment film obtained by applying the liquid crystal alignment agent of the present invention, and then fabricating liquid crystal cells using known methods and distributing liquid crystal within the liquid crystal cells. Specifically, the following two methods can be listed. The first method involves aligning two substrates with their respective liquid crystal alignment films facing each other, separated by a gap (cell gap). Then, the peripheries of the two substrates are bonded together using a sealant. Liquid crystal composition is injected into the cell gap separated by the substrate surface and the sealant until it contacts the film surface, and then the injection hole is sealed. The second method is called the ODF (One Drop Fill) method. A UV-curable sealant, for example, is applied to predetermined areas on one of two substrates on which a liquid crystal alignment film has already been formed. Then, liquid crystal composition is dropped onto predetermined points on the surface of the liquid crystal alignment film. Next, the other substrate is bonded together with the liquid crystal alignment films facing each other, spreading the liquid crystal composition across the entire substrate so that it contacts the film surface. Finally, the entire substrate is irradiated with UV light to harden the sealant. When using the first and second methods, it is advisable to heat the liquid crystal composition to a temperature at which it becomes an isotropic phase, and then slowly cool it to room temperature to remove the flow alignment during liquid crystal filling. Furthermore, when performing rubbing treatment on the coating, it is advisable to arrange the two substrates facing each other at a predetermined angle, such as orthogonal or antiparallel, according to the rubbing directions of each coating. The same applies to photoalignment treatment, where the alignment directions are arranged at a predetermined angle, such as orthogonal or antiparallel. For the sealant, epoxy resin containing a hardener and alumina spheres as spacers can be used. Examples of liquid crystals include nematic liquid crystals and smectic liquid crystals, with nematic liquid crystals being preferred. There are no particular restrictions on the liquid crystal composition. Liquid crystal compositions containing at least one liquid crystal compound (liquid crystal molecule) with positive dielectric anisotropy (positive liquid crystal composition, also called positive liquid crystal) or negative dielectric anisotropy (negative liquid crystal composition, also called negative liquid crystal) can be used, with negative liquid crystal materials being preferred. The aforementioned liquid crystal compositions may also contain liquid crystal compounds having fluorine atoms, hydroxyl groups, amino groups, fluorine-containing groups (e.g., trifluoromethyl), cyano groups, alkyl groups, alkoxy groups, alkenyl groups, isothiocyanate groups, heterocyclic rings, cycloalkanes, cycloalkenes, steroid skeletons, benzene rings, or naphthyl rings. They may also contain compounds with two or more rigid sites exhibiting liquid crystal properties (liquid crystal proto-skeleton) within the molecule (e.g., rigid biphenyl structures, or biphenyl structures linked by alkyl groups forming a double liquid crystal proto-skeleton compound, etc.). Liquid crystal compositions may also be nematic liquid crystal compositions, smectic liquid crystal compositions, or cholesterol liquid crystal compositions. Furthermore, in order to improve the alignment properties of the liquid crystal, additives may be added to the aforementioned liquid crystal composition. Examples of such additives include photopolymerizable monomers such as compounds with polymerizable groups, optically active compounds (e.g., Merck's S-811), antioxidants, ultraviolet absorbers, pigments, defoamers, polymerization initiators, or polymerization inhibitors. Positive liquid crystals include Merck's ZLI-2293, ZLI-4792, MLC-2003, MLC-2041, MLC-3019, and MLC-7081. Negative liquid crystals include, for example, Merck's MLC-6608, MLC-6609, MLC-6610, MLC-6882, MLC-6886, MLC-7026, MLC-7026-000, MLC-7026-100, and MLC-7029. Furthermore, in PSA mode, a liquid crystal containing a compound with polymerizable groups, such as Merck's MLC-3023, can be used. Then, polarizing plates are installed. Specifically, a pair of polarizing plates are attached to the surfaces of the two substrates opposite to the liquid crystal layer. Examples of polarizing plates include those made of a polarizing film called an "H-film," formed by extending polyvinyl alcohol along the alignment edges to absorb iodine using a cellulose acetate protective film, or polarizing plates composed of the H-film itself. [Example] The following examples illustrate the invention in more detail, but the invention is not limited thereto. The abbreviations of the compounds used and the methods for determining their properties are as follows. (Organic solvent) NMP: N-methyl-2-pyrrolidone; BCS: Butylceroxose (ethylene glycol monobutyl ether). (Tetracarboxylic acid dianhydride) [Chem. 14] (Diamine) [Chem. 15] (Terminal Modifier) ​​[Chem. 16] <Viscosity Measurement> A TVE-22H type E viscometer (manufactured by Toki Sangyo Co., Ltd.) was used to measure the viscosity at 25°C with a sample volume of 1.1 mL using a conical rotor TE-1 (1°34', R24). [Synthesis of Terminal Modifiers] AD-1 to AD-6 are novel compounds not disclosed in the literature, and their synthesis methods are detailed below. AD-7 was a commercially available product (manufactured by Merck). The products described in the following monomer synthesis examples 1-6 are based on... 1 ¹H-NMR analysis and identification (analytical conditions as follows). Apparatus: BRUKER ADVANCE III-500MHz; Solvent: deuterated dimethyl sulfoxide (DMSO-d). 6) or deuterated chloroform (CDCl) 3) Reference material: Tetramethylsilane (TMS) 1 H is δ 0.0 ppm) The abbreviations used in this invention have the following meanings: Boc 2O: Di-tert-butyl dicarbonate; THF: Tetrahydrofuran; DMF: N,N-dimethylformamide; EDC: 1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide; BOP reagent: Benzotriazolyl-N-hydroxy(dimethylamino)phosphonium hexafluorophosphide salt <Synthesis Example 1: Synthesis of AD-1> [Chemistry 17] <Synthesis of AD-1-1> 3,5-Diaminobenzoic acid (6.08 g, 40 mmol) and THF (50 g) were added to a flask and dissolved. Then, Boc was added to the flask. 2O (21.8 g, 100 mmol) was dissolved in a solution of THF (10 g), and the mixture was stirred at 60 °C for 15 hours to allow the reaction to proceed. After the reaction was complete, ethyl acetate (60 g) and pure water (60 g) were added, and the mixture was separated. The organic layer was washed twice with pure water. The obtained organic layer was concentrated and dried under vacuum at 40 °C to obtain AD-1-1. (Yield: 12.7 g, 36 mmol, white solid, yield: 90%). <Synthesis of AD-1> AD-1-1 (1.75 g, 4.96 mmol) and THF (12.3 g) were added to a flask and dissolved. EDC (1.16 g, 7.44 mmol) was added, and the mixture was stirred at room temperature (25 °C) for 30 minutes. Then, a solution of 3,4-dihydro-3-hydroxy-4-sideoxy-1,2,3-benzotriazine (0.816 g, 5.00 mmol) dissolved in THF (5.3 g) was added, and the mixture was stirred at room temperature (25 °C) for 15 hours. After the reaction was complete, ethyl acetate (18 g) and pure water (18 g) were added, and the mixture was separated. The organic layer was washed twice with pure water. The obtained organic layer was concentrated and dried under vacuum at 40 °C to obtain AD-1 (yield: 1.80 g, 3.62 mmol, brown solid, yield: 73%). The following is a summary of the process... 1 The H-NMR results confirmed that this solid was AD-1. 1 H-NMR (500MHz), at DMSO-d 6: δ (ppm) = 9.78 (s, 2H), 8.39-8.37 (m, 2H), 8.25-8.18 (m, 1H), 8.08-8.04 (m, 4H), 1.49 (s, 18H). <Synthesis Example 2: Synthesis of AD-2> [Chemistry 18] N,N'-bis(tert-butoxycarbonyl)-L-histidine (1.86 g, 5.23 mmol) and THF (18.6 g) were added to a flask and dissolved. EDC (0.812 g, 5.23 mmol) was added, and the mixture was stirred at room temperature (25 °C) for 30 minutes. Then, a solution of 3,4-dihydro-3-hydroxy-4-sideoxy-1,2,3-benzotriazine (0.853 g, 5.23 mmol) dissolved in THF (3.7 g) was added dropwise to the same flask, and the mixture was stirred at room temperature (25 °C) for 12 hours to allow the reaction to proceed. Ethyl acetate (37 g) and pure water (37 g) were added to the reaction mixture, and the mixture was separated. The organic layer was washed with a saturated sodium bicarbonate aqueous solution, and the obtained organic layer was concentrated to obtain crude AD-2. The crude sample was purified by silica gel column chromatography (dissolution solution: ethyl acetate / heptane = 1 / 1 (volume ratio)) to give AD-2 (yield: 1.10 g, 2.20 mmol, yellowish-brown solid, yield: 42%). From the following... 1 The H-NMR results confirmed that the solid was AD-2. 1 H-NMR (500MHz), at DMSO-d 6: δ(ppm)=8.35-8.32(m,2H), 8.22-8.18(m,2H), 8.05-8.02(m,1H), 7.74-7.72(m, 1H), 7.43-7.38(m,1H), 4.84-4.79(m,1H), 3.32-3.07(m,2H), 1.58-1.42(m,18H). <Synthesis Example 3: Synthesis of AD-3> [Chemistry 19] N-(tert-butoxycarbonyl)glycine (3.50 g, 20.0 mmol) and dichloromethane (35 g) were added to a flask and dissolved. EDC (3.26 g, 21.0 mmol) was added, and the mixture was stirred at room temperature (25 °C) for 30 minutes. Then, 3,4-dihydro-3-hydroxy-4-sideoxy-1,2,3-benzotriazine (3.59 g, 22.0 mmol) was added, and the mixture was stirred at room temperature (25 °C) for 18 hours to allow the reaction to proceed. After the reaction was complete, dichloromethane (35 g) and pure water (35 g) were added, and the mixture was separated. The obtained organic layer was washed with a saturated sodium bicarbonate aqueous solution, and the organic layer was concentrated to obtain crude AD-3. Heptane and ethyl acetate were added to the crude layer, and the mixture was heated to 50 °C to dissolve it. After cooling to room temperature, crystals were precipitated. Fractional filtration and crystallization were performed, followed by vacuum drying at 40°C to obtain AD-3 (yield: 1.41 g, 4.40 mmol, white solid, yield: 22%). As shown below... 1 The H-NMR results confirmed that the solid was AD-3. 1 H-NMR (500MHz), at DMSO-d 6: δ (ppm) = 8.35-8.33 (m, 2H), 8.22-8.20 (m, 1H), 8.05-8.04 (m, 1H), 7.60 (s, 1H), 4.30-4.22 (m, 2H) 1.41 (s, 9H) <Synthesis Example 4: Synthesis of AD-4> [Chemistry 20] N,N'-di-tert-butoxycarbonyl-histidine (17.7 g, 49.8 mmol), triethylamine (6.28 g, 62.1 mmol), and dichloromethane (247 g) were added to a flask, and the resulting solution was cooled to 2°C. Then, BOP reagent (22.1 g, 50.0 mmol) was added to the flask, and the mixture was stirred at 10°C for 1 hour to allow the reaction to proceed. The precipitated crystals were filtered off, washed twice with 2-propanol (70.0 g), and twice with acetonitrile (70.0 g). The resulting wet product was dried under vacuum at 40°C to obtain AD-4 (yield: 8.31 g, 17.6 mmol, appearance: white solid, yield: 35%). The following is a summary of the process... 1 The H-NMR results confirmed that the solid was AD-4. 1 H-NMR (500MHz), at CDCl 3: δ (ppm) = 8.09 (d, 1H, J = 1.0Hz), 8.03 (d, 1H, J = 8.4Hz), 7.61 (d, 1H, J = 8.3Hz), 7.52 (t, 1H, J = 7.2Hz), 7.41 (t, 1H, J=8.0Hz), 7.38(s,1H), 6.18(d,1H,J=7.0Hz), 4.99(q,1H,J=6.7Hz), 3.39-3.25(m,2H), 1.63(s,9H), 1.48(s,9H) <Synthesis Example 5: Synthesis of AD-5> [Chemistry 21] In a flask, 4-(tert-butoxycarbonylamino)benzoic acid (5.12 g, 21.6 mmol) was dissolved in DMF (51 g), and 3,4-dihydro-3-hydroxy-4-sideoxy-1,2,3-benzotriazine (3.88 g, 23.8 mmol) was added. The mixture was stirred at room temperature (25 °C) for 30 minutes. Then, EDC (3.52 g, 22.7 mmol) was added to the reaction mixture, and the mixture was stirred at room temperature (25 °C) for 18 hours to allow the reaction to proceed. After the reaction was complete, pure water (150 g) and toluene (100 g) were added, and the mixture was separated. The obtained organic layer was washed with a saturated sodium bicarbonate aqueous solution, resulting in the precipitation of a white solid. This solid was filtered and dried under vacuum at 40 °C to obtain AD-5 (yield: 7.10 g, 18.6 mmol, 86%). The following is a summary of the process... 1 The H-NMR results confirmed that the solid was AD-5. 1 H-NMR (500MHz), at DMSO-d 6: δ (ppm) = 10.01 (s, 1H), 8.39-8.36 (m, 2H), 8.24-8.22 (m, 1H), 8.16-8.14 (m, 2H), 8.06-8.04 (m, 1H), 7.85-7.78 (m, 2H), 1.50 (s, 9H) <Synthesis Example 6: Synthesis of AD-6> [Chemistry 22] Using 3-(terbutoxycarbonylamino)benzoic acid instead of 4-(terbutoxycarbonylamino)benzoic acid, the same procedure as in Monomer Synthesis Example 5 was performed to obtain AD-6 (yield: 4.70 g, 12.3 mmol, yield: 93%). As shown below... 1 The H-NMR results confirmed that the solid was AD-6. 1 H-NMR (500MHz), at DMSO-d 6: δ(ppm)=9.82(s,1H), 8.50(s,1H), 8.40-8.37(m,2H), 8.25-8.22(m,1 H), 8.08-8.05(m,1H), 7.85-7.82(m,2H), 7.62-7.59(m,1H), 1.50(s,9H) [Polymer Synthesis] <Synthesis Example 1> DA-1 (1.08 g, 9.99 mmol), DA-2 (3.66 g, 15.0 mmol), DA-3 (4.81 g, 15.0 mmol), DA-4 (3.98 g, 9.99 mmol), and NMP (132.0 g) were added to a 100 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube. The mixture was stirred at room temperature for 1 hour while supplying nitrogen. Then, CA-1 (10.6 g, 47.2 mmol) and NMP (44.4 g) were added, and the mixture was stirred at 40 °C for 12 hours to obtain a polyacrylic acid (PAA-0) solution with a solid content concentration of 12% by mass (viscosity: 440 mPa·s). <Synthesis Example 2> A solution of polyacrylic acid PAA-0 (40.0 g) was measured into a 50 mL Erlenmeyer flask equipped with a stir bar, and the end-modifying agent AD-1 (1.00 g, 1.094 mmol) was added. The mixture was stirred at 40 °C for 12 hours to obtain a solution of end-modified polyacrylic acid (PAA-1). <Synthesis Examples 3-8> AD-1, which is used as an end modifier, was replaced with AD-2 to AD-7, each of which was added at 1.094 mmol. Otherwise, the same procedure as in Synthesis Example 2 was followed to obtain solutions of end-modified polyacrylic acids (PAA-2) to (PAA-7). <Synthesis Example 9> DA-5 (1.59 g, 7.98 mmol), DA-6 (0.790 g, 2.65 mmol), DA-7 (1.12 g, 2.66 mmol), and NMP (47.8 g) were added to a 50 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube. The mixture was stirred at room temperature for 1 hour while supplying nitrogen. Then, CA-2 (3.73 g, 12.7 mmol) and NMP (5.30 g) were added, and the mixture was stirred at 70 °C for 12 hours to obtain a polyacrylic acid (PAA-B1) solution with a solid content of 12% by mass (viscosity: 390 mPa·s). [Preparation of Sample Solution] <Comparative Example 1> A solution (1.50 g) of polyacrylic acid (PAA-0) obtained in Synthesis Example 1 was measured into a 50 mL Erlenmeyer flask equipped with a stir bar, and a solution (3.50 g) of polyacrylic acid (PAA-B1) obtained in Synthesis Example 9 was added. Then, NMP (2.00 g) and BCS (3.00 g) were added, and the mixture was stirred overnight with a magnetic stirrer to obtain the liquid crystal alignment agent (AL-C1). <Examples 1-7> Polyamide (PAA-0) was replaced with (PAA-1) to (PAA-7), 1.50 g of each, and liquid crystal alignment agents (AL-1) to (AL-7) were obtained following the same procedure as in Comparative Example 1. The sample solutions prepared above are summarized in Table 1 below. [Table 1] [Creation of Liquid Crystal Cells] A liquid crystal cell with an FFS mode liquid crystal display element is fabricated. First, a substrate with electrodes is prepared. The substrate is a rectangular glass substrate with a thickness of 0.7 mm and a diameter of 35 mm × 40 mm. An ITO electrode (thickness: 50 nm, electrode width: 20 mm vertically and 10 mm horizontally) with a full-page pattern is formed on the substrate to form the first opposing electrode. A SiN (silicon nitride) film formed by CVD (chemical vapor deposition) is formed on the first opposing electrode as the second layer. The second SiN film is a 300 nm thick film that acts as an interlayer insulating film. On the second SiN film, a comb-shaped pixel electrode formed by patterning the ITO film is placed as the third layer, forming two pixels, the first pixel and the second pixel. Each pixel is 10 mm vertically and approximately 5 mm horizontally. At this point, the first layer's opposing electrode and the third layer's pixel electrode are electrically insulated by the SiN film of the second layer. The third layer's pixel electrode has a 3μm wide electrode element with a central portion bent at an inner angle of 160°, which is arranged in a comb-like shape with multiple parallel teeth spaced 6μm apart. Each pixel has a first region and a second region, with the line connecting the bent portions of multiple electrode elements as the boundary. Then, the liquid crystal alignment agents AL-Cl and AL-1 to AL-7 obtained in Comparative Example 1 and Examples 1 to 7 are filtered through a filter with a pore size of 1.0μm and then spin-coated onto the surface of the prepared electrode substrate (first glass substrate) and the surface of the glass substrate (second glass substrate) with a columnar spacer having a height of 4μm on the back side where an ITO film has been formed. Then, it is dried on a hot plate at 80°C for 2 minutes, followed by calcination in an IR oven at 230°C for 30 minutes to form a coating film with a thickness of 100 nm. This coating film is then irradiated with 500 mJ / cm² ultraviolet light of 254 nm wavelength, linearly polarized with an extinction ratio of 26:1, through a polarizing plate. 2The substrate is then subjected to alignment treatment and calcined in an IR oven at 230°C for 30 minutes to obtain a substrate with a liquid crystal alignment film. Furthermore, the liquid crystal alignment film formed on the electrode-attached substrate is aligned such that the direction in which the inner angles of the pixel bends are equally divided is perpendicular to the alignment direction of the liquid crystal. The liquid crystal alignment film formed on the second glass substrate is aligned such that the alignment direction of the liquid crystal on the first glass substrate is aligned with the alignment direction of the liquid crystal on the second glass substrate during the fabrication of the liquid crystal cell. The two substrates are grouped together, and a sealant (Mitsui Chemicals XN-1500T) is printed around the liquid crystal injection port. Another substrate is then attached, ensuring that the alignment direction facing the liquid crystal alignment film is 0°. The sealant is then heat-treated at 150°C for 60 minutes to harden and create a void cell. Liquid crystal MLC-3019 (Merck) is injected into this void cell using a depressurized injection method, and the injection port is sealed to obtain an FFS-driven liquid crystal cell. The obtained liquid crystal cells were then heated at 120°C for 1 hour and left to stand overnight before being evaluated. [Evaluation of In-Plane Uniformity of Contrast Ratio] The variation in the torsion angle of liquid crystal cells was evaluated using an AxoStep high-precision Mueller matrix imaging polarimeter manufactured by AXOMETRICS. The liquid crystal cells fabricated above were placed on a measurement stage, and the distribution of circular retardation within the pixel plane was measured without applied voltage. The standard deviation σ was calculated as 3σ times the standard deviation σ. For in-plane uniformity, a smaller 3σ value is considered better. Based on the evaluation criteria, a 3σ value of 1.50 or less is rated as "◎", a value greater than 1.50 but less than 2.00 is rated as "○", and a value greater than 2.00 is rated as "×". The evaluation results of the in-plane uniformity of contrast ratio in Comparative Example 1 and Examples 1-7 are shown in Table 2 below. [Table 2] As shown in Table 2, the liquid crystal alignment films obtained using liquid crystal alignment agents AL-1 to AL-7 of Examples 1 to 7, which contain polyamide end-modified by end-modifying agents AD-1 to AD-7, exhibit better in-plane uniformity of contrast compared to the liquid crystal alignment film obtained using liquid crystal alignment agent AL-C1 of Comparative Example 1, which does not contain end-modified polyamide. [Industrial Applicability] The liquid crystal alignment film obtained from the liquid crystal alignment agent of this invention can be appropriately used in various liquid crystal display elements, such as those using IPS driving and FFS driving methods. Furthermore, these display elements are not limited to liquid crystal displays for display purposes; they are also useful in dimming windows, shutters, and other applications that control light transmission and block light. Furthermore, the entire contents of the specification, scope of the patent application and abstract of Japanese Patent Application No. 2021-170564, filed on October 18, 2021, are hereby cited and used as disclosure in the specification of this invention.

Claims

1. A liquid crystal alignment agent comprising a polymer (A), wherein the polymer (A) is selected from one or more of the following groups: a tetracarboxylic acid derivative component comprising at least one compound selected from the group consisting of tetracarboxylic acid dianhydrides and their derivatives, a diamine component, and an active ester compound (B) represented by formula (1), a polyimide precursor obtained by reacting the polyimide precursor with an active ester compound (B), and a polyimide derivative thereof; wherein the proportion of the active ester compound (B) used is 0.01 to 50 mol parts relative to a total of 100 mol parts of the diamine component used, and the polymer (A) contains a group represented by formula (1A) from the active ester compound (B). In formula (1), W represents an organic group with 1 to 30 carbon atoms that has a protected amine site and is not a Boc group, and is selected from the group consisting of *1-NH(Boc), *1-N(Boc)2, and "*1-N(Boc)-*1" (*1 represents an atomic bond to a carbon atom). W is obtained by removing the carboxyl group from a carboxylic acid (W) represented by "W-COOH". The carboxylic acid (W) is obtained by protecting the amine group of a carboxyl-containing monoamine (mA) or a carboxyl-containing polyamine (pA) with two or more amine groups. The monoamine (mA) is an aromatic monoamine or an aliphatic monoamine, and the polyamine (pA) is an aromatic polyamine or an aliphatic polyamine. Boc represents a terbutoxycarbonyl group, and R represents an active ester-forming group. However, when R represents a group derived from N-hydroxysuccinimide, W has two or more of these protected amine sites. In formula (1A), W is synonymous with formula (1), and * represents the atomic bond of polymer bonding.

2. The liquid crystal alignment agent as claimed in claim 1, wherein, The R group is derived from a hydroxyl group selected from 1-hydroxybenzotriazole, 1-hydroxy-7-azabenzotriazole, N-hydroxysuccinimide, 2-cyano-2-(hydroxyimino)ethyl acetate, 3,4-dihydro-3-hydroxy-4-sideoxy-1,2,3-benzotriazole, N-hydroxy-5-norcamphene-2,3-dicarboxylated imidin, 2,3,4,5,6-pentafluorophenol, and 6-chloro-1-hydroxy-1H-benzotriazole by removing the hydroxyl group.

3. The liquid crystal alignment agent as claimed in claim 1, wherein, The polyamine (pA) is a diaminobenzoic acid, a carboxybiphenyl compound, a carboxydiphenyl alkyl compound, or a carboxydiphenyl ether, or a heterocycle containing a nitrogen atom or a derivative thereof.

4. The liquid crystal alignment agent as claimed in claim 3, wherein, The carboxylic acid (W), monoamine (mA), and polyamine (pA) have a nitrogen-containing heterocycle or a derivative thereof.

5. The liquid crystal alignment agent as requested in item 1 or 2, wherein, The active ester compound (B) is at least one of the compounds represented by formulas (b-1) to (b-7).

6. The liquid crystal alignment agent as requested in item 1 or 2, wherein, The tetracarboxylic acid derivative contains a tetracarboxylic acid dianhydride represented by formula (2), where X represents a structure selected from the group consisting of formulas (x-1)~(x-17) and formulas (xr-1)~(xr-2). In formula (x-1), R1 to R4 each independently represent a hydrogen atom, a halogen atom, an alkyl group with 1 to 6 carbon atoms, an alkenyl group with 2 to 6 carbon atoms, an alkoxy group with 2 to 6 carbon atoms, a fluorine-containing monovalent organic group with 1 to 6 carbon atoms, an alkoxy group with 1 to 6 carbon atoms, an alkoxyalkyl group with 2 to 6 carbon atoms, an alkoxycarbonyl group with 2 to 6 carbon atoms, or a phenyl group. In formula (x-7), R5 and R6 each independently represent a hydrogen atom or a methyl group. In formulas (xr-1) to (xr-2), j and k are integers of 0 or 1. A1 and A2 each independently represent a single bond, -O-, -CO-, -COO-, phenyl, sulfonyl, or amide group. The multiple A2s in formula (xr-2) may be the same or different. *1 refers to an atomic bond bonded to one of the anhydride groups, and *2 refers to an atomic bond bonded to another anhydride group.

7. The liquid crystal alignment agent as claimed in claim 6, wherein, Formula (x-1) is selected from the group consisting of formulas (x1-1) to (x1-6), where *1 is an atomic bond bonded to one of the anhydride groups and *2 is an atomic bond bonded to the other anhydride group.

8. The liquid crystal alignment agent as requested in item 1 or 2, wherein, The diamine component contains a diamine represented by the following formula (3), in which Ar1 and Ar1' each independently represent a benzene ring, a biphenyl structure, or a naphthalene ring. One or more hydrogen atoms on the benzene ring, the biphenyl structure, or the naphthalene ring can also be replaced by a monovalent group. L1 and L1' each independently represent a single bond, -O-, -C(=O)-, -C(=O)-O-, or -OC(=O)-. A represents a divalent organic group formed by inserting at least one of -O-, -C(=O)-O-, and -OC(=O)- between the carbon-carbon bonds of -CH2-, an alkyl group with 2 to 12 carbon atoms, or an alkyl group with 2 to 12 carbon atoms inserted between the carbon-carbon bonds of the alkyl group. Any hydrogen atom in A can also be replaced by a halogen atom.

9. A method for manufacturing a liquid crystal alignment film, comprising the following steps: coating a liquid crystal alignment agent as claimed in any one of claims 1 to 8 onto a substrate and calcining it, and irradiating the obtained film with polarized radiation as needed.

10. A method for manufacturing the liquid crystal alignment film as claimed in claim 9, wherein, The calcination temperature is 150~250℃.

11. A liquid crystal alignment film formed from a liquid crystal alignment agent as claimed in any one of claims 1 to 8.

12. A liquid crystal display element comprising a liquid crystal alignment film as claimed in claim 11.

13. The liquid crystal display element in request item 12 is driven by either IPS or FFS.

14. A compound represented by the formulas (b-1) to (b-6), .

15. A polymer (A) comprising one or more of the following: a polyimide precursor obtained by reacting a tetracarboxylic acid derivative component, a diamine component, and an active ester compound represented by formulas (b-1) to (b-7) thereof, or a polyimide comprising a amide of the polyimide precursor, wherein the polymer (A) contains a group derived from the active ester compound.