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

Abstract

Provided are: a liquid crystal aligning agent that contains two or more kinds of polyamic acids and in which fluctuation of the pretilt angle of a liquid crystal alignment film that occurs when stored at room temperature is suppressed; a liquid crystal alignment film obtained from the liquid crystal aligning agent; and a liquid crystal display element.　The liquid crystal aligning agent is capable of forming a liquid crystal alignment film having a pretilt angle of 0° or more and less than 3°, and is characterized by containing a polymer (A) and a polymer (B), or a polymer (B) and a polymer (B'), as indicated below. (The polymer (A) excludes the polymer (B).)　Polymer (A): A polyamic acid (A) having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, wherein the polyamic acid contains: a structural unit (a-1Ta) represented by the formula (1Ta) as the structural unit derived from the tetracarboxylic acid derivative; and a structural unit (a-1Da) represented by the formula (1Da) as the structural unit derived from the diamine.　Polymer (B): A polyamic acid (B) having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, wherein the polyamic acid contains: a structural unit (b-1Tb) represented by the formula (1Tb) as the structural unit derived from the tetracarboxylic acid derivative; and a structural unit (b-1Db) represented by the formula (1Db) as the structural unit derived from the diamine. At least some of the terminals of the polyamic acid (B) contain a non-amino group, the non-amino group being a functional group represented by the structural formula (E). The abundance ratio of the terminal amino group of the polyamic acid (B) is not greater than 60% with respect to all terminals of the polyamic acid (B).　Polymer (B'): A polyamic acid (B') having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, wherein the polyamic acid contains a structural unit (b-1Tb) represented by the formula (1Tb) as the structural unit derived from the tetracarboxylic acid derivative, does not contain the structural unit (a-1Da) represented by the formula (1Ta), and contains a structural unit (b-1Db) represented by the formula (1Db) or a structural unit (b-1Db') represented by the formula (1Db') as the structural unit derived from the diamine. The abundance ratio of the terminal amino group of the polyamic acid (B') is greater than 60% with respect to all terminals of the polyamic acid (B).

Description

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

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

[0002] Liquid crystal display devices have traditionally been widely used as display units for personal computers, smartphones, mobile phones, television receivers, etc. Liquid crystal display devices include, for example, a liquid crystal layer sandwiched between an element substrate and a color filter substrate, pixel electrodes and a common electrode that apply an electric field to the liquid crystal layer, an alignment film that controls the alignment of liquid crystal molecules in the liquid crystal layer, and thin film transistors (TFTs) that switch electric signals supplied to the pixel electrodes. Known methods for driving liquid crystal molecules include vertical electric field methods such as the TN (Twisted Nematic) method and the VA (Vertical Alignment) method, and horizontal electric field methods such as the IPS (In-Plane Switching) method and the FFS (Fringe Field Switching) method.

[0003] Currently, the most widely used liquid crystal alignment films in industry are prepared by rubbing the surface of a film made of a polymer, typically polyamic acid and / or imidized polyimide, formed on an electrode substrate in one direction with a cloth made of cotton, nylon, polyester, or the like, a so-called rubbing treatment. In recent years, as liquid crystal display elements have become increasingly sophisticated, high-definition, and large, photoalignment methods have been investigated, in which liquid crystal alignment ability is imparted by irradiating the display with polarized radiation. Photoalignment methods utilizing photoisomerization reactions, photocrosslinking reactions, photodecomposition reactions, and the like have been proposed (see, for example, Non-Patent Document 1 and Patent Document 1). Furthermore, as the performance of liquid crystal display elements has improved, liquid crystal display elements have been used in applications such as large-screen, high-definition liquid crystal televisions, as well as in in-vehicle applications such as car navigation systems, meter panels, and monitors for surveillance cameras and medical cameras. In response to demands for viewing angle characteristics, IPS and FFS modes, which offer superior viewing angle characteristics, have been considered among the liquid crystal molecule driving modes.

[0004] Japanese Patent Application Publication No. 9-297313

[0005] "Liquid Crystal Photo-Alignment Film" Kidowaki, Ichimura, Functional Materials, November 1997, Vol. 17, No. 11, pp. 13-22

[0006] Polyimide-containing liquid crystal aligning agents have been actively investigated as liquid crystal aligning agents for liquid crystal alignment films used in in-plane switching mode liquid crystal display devices. However, while polyimide has excellent liquid crystal alignment properties, it suffers from poor solubility in organic solvents. Therefore, when dissolving polyimide in an organic solvent, highly soluble polar organic solvents such as N-methylpyrrolidone are used. However, while polar organic solvents have high solubility, they also suffer from high hygroscopicity. Therefore, when preparing a liquid crystal alignment film using a liquid crystal aligning agent containing such a polar organic solvent, it is necessary to control the application environment of the liquid crystal aligning agent in order to improve the performance of the resulting liquid crystal alignment film. In particular, application in a humid environment can reduce the solubility of the liquid crystal aligning agent due to moisture absorption before heat treatment, resulting in precipitation of polyimide and whitening of the liquid crystal alignment film (hygroscopic whitening). Furthermore, the production of polyimide requires large amounts of reagents and large manufacturing equipment, posing challenges in terms of handleability (safety, environmental impact, equipment costs, etc.). In light of the above circumstances, the present inventors focused on liquid crystal aligning agents using polyamic acid. However, it has been found that the use of a liquid crystal aligning agent containing two or more types of polyamic acids with different properties is preferable from the viewpoints of suppressing the above-mentioned whitening due to moisture absorption and ease of handling, but that the pretilt angle characteristics of the liquid crystal alignment film change during storage. In particular, liquid crystal alignment films used in liquid crystal display elements typified by IPS mode and FFS mode are required to have a low pretilt angle of 0° or more and less than 3° in order to improve viewing angle characteristics. In situations where such a low pretilt angle is required, the above-mentioned fluctuation in the pretilt angle is undesirable, and it has been desired to suppress it to a high level.

[0007] In view of the above, an object of the present invention is to provide a liquid crystal alignment agent containing two or more types of polyamic acids, which suppresses fluctuations in the pretilt angle of a liquid crystal alignment film that occur during storage at room temperature, a liquid crystal alignment film obtained from the liquid crystal alignment agent, and a liquid crystal display element.

[0008] As a result of intensive research to achieve the above object, the present inventors have found that using a liquid crystal aligning agent containing a first polyamic acid having a specific non-amino terminal structure and having a structural unit derived from a specific tetracarboxylic acid derivative and a structural unit derived from a diamine, and a second polyamic acid having a structural unit derived from a specific tetracarboxylic acid derivative and a structural unit derived from a diamine, is extremely effective for achieving the above object, and have completed the present invention.

[0009] The present invention encompasses the following aspects: A liquid crystal aligning agent capable of forming a liquid crystal alignment film having a pretilt angle of 0° or more and less than 3°, the liquid crystal aligning agent comprising the following polymer (A) and polymer (B), or polymer (B) and polymer (B'). (However, polymer (A) excludes polymer (B).) Polymer (A): Polyamic acid (A) having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, wherein the structural unit derived from the tetracarboxylic acid derivative is a polyamic acid (A) having the following formula (1T ａ As a diamine-derived structural unit, a structural unit (a-1Ta) represented by the following formula (1D ａ Polymer (B): The polyamic acid (B) has a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, wherein the structural unit derived from the tetracarboxylic acid derivative is represented by the following formula (1T ｂ As a diamine-derived structural unit, a structural unit (b-1Tb) represented by the following formula (1D ｂ ), at least a part of the terminals of the polyamic acid (B) contain a non-amino group, and the non-amino group is a functional group represented by the following structural formula (E), and the abundance rate of the terminal amino groups in the polyamic acid (B) is 60% or less based on all the terminals of the polyamic acid (B). Polymer (B'): The polyamic acid (B') has a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, and the structural unit derived from the tetracarboxylic acid derivative contains a structural unit (b-1Db) represented by the following structural formula (1T ｂ) and the structural unit (b-1Tb) represented by the above formula (1T ａ As a diamine-derived structural unit, the structural unit (a-1Da) represented by the following formula (1D ｂ ) or a structural unit (b-1Db) represented by the following formula (1D ｂ’ ), and the abundance rate of terminal amino groups in the polyamic acid (B') is greater than 60% based on all terminals of the polyamic acid (B). (X in the formula ａ is a tetravalent organic group represented by the following formula (x-2), or a tetravalent organic group having an alicyclic structure of five or more members (T ５ａ ) is represented by the formula (1D ａ ) in Y ａ represents a divalent organic group derived from a diamine. Each Z independently represents a hydrogen atom or a monovalent organic group. (X in the formula ｂ represents a tetravalent organic group derived from an aromatic tetracarboxylic dianhydride. ｂ ) in Y ｂ is diamine (0) "H-N(Z)-Ar １ -L １ -A-L １’ -Ar １’ -N(Z)-H" or diamine(0') "H-N(Z)-Ar ２ -L ２ -A ２ -L ２’ -Ar ２’ represents a divalent organic group derived from "-N(Z)-H". １ , Ar １’ each independently represents a benzene ring, a biphenyl structure, or a naphthalene ring. １ , Ar １’ Any hydrogen atom on the ring may be substituted with a monovalent group. A represents a divalent organic group having an alkylene structure and having 1 to 10 carbon atoms. L １ , L １’are each independently a single bond, -O-, -S-, -C(=O)-, -O-C(=O)-, -NR- (R represents a hydrogen atom or a monovalent organic group), -C(=O)-NR- (R represents a hydrogen atom or a monovalent organic group), or -NR-C(=O)- (R represents a hydrogen atom or a monovalent organic group). ２ and Ar ２’ each independently represents a benzene ring, a biphenyl structure, a naphthalene ring, or an aromatic heterocycle. ２ and Ar ２’ Any hydrogen atom on the ring of A may be substituted with a monovalent group. ２ represents a divalent organic group having an alkylene group. ２ , L ２’ are each independently a single bond, -O-, -S-, -C(=O)-, -O-C(=O)-, -NR- (R represents a hydrogen atom or a monovalent organic group), -C(=O)-NR- (R represents a hydrogen atom or a monovalent organic group), or -NR-C(=O)- (R represents a hydrogen atom or a monovalent organic group). ２ and Ar ２’ and A ２ Z is a group represented by the above formula (1D ａ ) is synonymous with Z in (In formula (E), Q is a monovalent organic group selected from any of the following groups (e1) to (e3). * represents a bond.) (e1) an acyclic hydrocarbon group having 1 to 6 carbon atoms; (e2) a monovalent organic group having 1 or 2 carboxy groups and 2 to 30 carbon atoms (provided that the monovalent organic group does not contain an acid anhydride group); (e3) a monovalent organic group having two or more Boc groups and having 1 to 30 carbon atoms excluding Boc, the monovalent organic group being selected from the group consisting of *1-NH(Boc), *1-N(Boc), ２ and "*1-N(Boc)-*1" (*1 represents a bond bonded to a carbon atom). When there are two or more protected amino moieties, the respective protected amino moieties may be the same or different. (Formula (1D ｂ’ ) in Y ｂ’ is a diamine (1) "H-N(Z)-Ar３ represents a divalent organic group derived from the group consisting of Ar, Ar(Z), ... ３ is -Ar ４ -NR １ -Ar ４’ -, -Ar ４１ -Ar ４２ -, or three or more cyclic groups selected from the group consisting of a benzene ring and a heterocycle are directly or ２ The divalent organic group is bonded to two -N(Z)- groups via aromatic carbon atoms contained in a benzene ring or a heterocycle, and the two aromatic carbon atoms are not contained in the same cyclic group. ４ and Ar ４’ each represents a benzene ring or an aromatic heterocycle. ４１ and Ar ４２ each represents a benzene ring or an aromatic heterocycle, and Ar ４１ and Ar ４２ One of Ar represents a benzene ring, and the other represents an aromatic heterocycle. ３ Any hydrogen atom on the benzene ring or aromatic heterocycle of Ar １ , Ar １’ may be substituted with a monovalent group exemplified by —NR １ -, -NR ２ R in - １ , R ２ , represents a hydrogen atom or a monovalent organic group.

[0010] According to the present invention, it is possible to provide a liquid crystal alignment agent containing two or more types of polyamic acids, in which fluctuations in the pretilt angle of a liquid crystal alignment film that occur during storage at room temperature are suppressed, a liquid crystal alignment film obtained from the liquid crystal alignment agent, and a liquid crystal display element.

[0011] 1 is a schematic cross-sectional view showing an example of an IPS mode in-plane switching liquid crystal display element having a liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention, and FIG. 2 is a schematic cross-sectional view showing an example of an FFS mode in-plane switching liquid crystal display element having a liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention.

[0012] A liquid crystal aligning agent containing a specific polymer component, a liquid crystal alignment film formed using the liquid crystal aligning agent, and a liquid crystal display element having the liquid crystal alignment film will be described in detail below. However, the following description of the constituent elements is an example of one embodiment of the present invention, and the present invention is not limited to these details. In the following description, examples of "halogen atom" include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Furthermore, "tert-", which means tertiary, is also represented as "t-". "Boc" represents a tert-butoxycarbonyl group, and "*" represents a bond.

[0013] (Pretilt Angle) The liquid crystal aligning agent of the present invention is capable of forming a liquid crystal alignment film having a pretilt angle of 0° or more and less than 3°, and contains the above-mentioned polymer (A) and polymer (B), or polymer (B) and polymer (B'). (However, polymer (A) excludes polymer (B).) The term "pretilt angle" refers to the angle between the long axis of horizontally aligned liquid crystal molecules and the substrate surface. This angle occurs when, for example, a resin film containing polyimide or its precursor is subjected to an alignment treatment such as rubbing alignment treatment, and the rubbing roller comes into contact with the surface of the resin film containing polyimide or its precursor, causing the polymer chains on that surface to tilt. A smaller pretilt angle is desirable from the viewpoint of viewing angle characteristics.

[0014] (Terminal Amino Group) At least some of the terminals of the polyamic acid (B) in the polymer (B) contained in the liquid crystal aligning agent of the present invention contain a non-amino group, and the non-amino group is a functional group represented by the structural formula (E) above. That is, preferably, at least some of the terminal amino groups in the polyamic acid (B) are modified to have the non-amino group. The abundance rate of the terminal amino groups in the polyamic acid (B) is 60% or less, based on all terminals of the polyamic acid (B). Note that "based on all terminals of the polyamic acid (B)" refers to the case where the total number of amino terminals and non-amino terminals in the polyamic acid (B) is 100%, and includes the case where either terminal is 0%. Note that at least some of the terminals of the polyamic acid (A) in the polymer (A) of the present invention may contain the non-amino group. That is, preferably, at least some of the terminal amino groups in the polyamic acid (A) may be modified to have the non-amino group. From the viewpoint of suitably obtaining the effects of the present invention, the non-amino group that the polyamic acid (A) may contain at its terminal may be a functional group represented by structural formula (E) exemplified for the polyamic acid (B) in the polymer (B), and a similar functional group is a preferred embodiment.

[0015] The "abundance rate of terminal amino groups" referred to here is, for example, in the case of polyamic acid (B), the proportion of terminals that are amino groups, expressed as a percentage, based on all terminals of polyamic acid (B). The abundance rate of terminal amino groups is １ This can be estimated from the change in peak intensity of the terminal amino group using H-NMR. The abundance of terminal amino groups in the polyamic acid (B) used in the present invention is preferably 30% or less, more preferably 10% or less, and even more preferably 1% or less. The abundance of terminal amino groups in the polyamic acid (B) used in the present invention may be 0%. That is, all of the terminals of the polyamic acid (B) used in the present invention may contain the non-amino group.

[0016] The non-amino group is a functional group represented by the structural formula (E). The functional group represented by the structural formula (E) is preferably bonded to a nitrogen atom of the diamine residue. Preferred examples of (e1) include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a vinyl group, and a methacrylic group. Preferred examples of (e1) include residues derived from acyclic aliphatic dicarboxylic acid anhydrides such as acetic anhydride, acrylic anhydride, methacrylic anhydride, propionic anhydride, butyric anhydride, valeric anhydride, isovaleric anhydride, hexanoic anhydride, or heptanoic anhydride.

[0017] A preferred example of (e2) above is a monovalent organic group having a residue derived from a dicarboxylic acid anhydride and one to two carboxy groups (however, the monovalent organic group does not include an acid anhydride group). Specific examples of dicarboxylic acid anhydrides that provide (e2) above include a compound (e2-1) that does not have an alkoxysilane structure and a compound (e2-2) that has an alkoxysilane structure. Specific examples of compound (e2-1) include aromatic or aliphatic cyclic dicarboxylic acid anhydrides such as phthalic anhydride, maleic anhydride, succinic anhydride, allylsuccinic anhydride, itaconic anhydride, trimellitic anhydride, 1,2,4-cyclohexanetricarboxylic acid-1,2-anhydride, 4-ethynylphthalic anhydride, or cyclohexene-1,2-dicarboxylic acid anhydride. The aliphatic ring in the aliphatic cyclic dicarboxylic acid anhydride may be a saturated aliphatic ring or an unsaturated aliphatic ring.Specific examples of compound (e2-2) include 3-trimethoxysilylpropyl succinic anhydride, 3-triethoxysilylpropyl succinic anhydride, 4-(3-trimethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-triethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-trimethoxysilylpropyl)phthalic anhydride, 4-(3-triethoxysilylpropyl)phthalic anhydride; (C1 to C6)alkoxydimethylsilyl(C2 to C8)alkyl succinic anhydrides such as 2-(methoxydimethylsilyl)ethyl succinic anhydride, 3-(dimethylmethoxysilyl)propyl succinic anhydride, and 3-(dimethylethoxysilyl)propyl succinic anhydride; 2-(dimethoxymethylsilyl)ethyl succinic anhydride Examples of the di(C1-C6)alkoxymethylsilyl(C2-C8)alkyl succinic anhydride such as succinic acid; tri(C1-C6)alkoxysilyl(C2-C8)alkyl succinic anhydride such as 2-(trimethoxysilyl)ethyl succinic anhydride, 2-(triethoxysilyl)ethyl succinic anhydride, [3-(trimethoxysilyl)propyl]succinic anhydride, or [3-(triethoxysilyl)propyl]succinic anhydride; 4-(3-dimethylmethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-dimethylethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-dimethylethoxysilylpropyl)phthalic anhydride, or 4-(3-dimethylethoxysilylpropyl)phthalic anhydride.

[0018] In the above (e3), from the viewpoint of suitably obtaining the effects of the present invention, the number of protected amino moieties is 1 or more, and from the viewpoint of the effect of liquid crystal alignment, the number of protected amino moieties is preferably 4 or less. The above (e3) can be obtained, for example, using an active ester compound (e) represented by R-O-C(═O)-E3 (R represents an active ester-forming group, and E3 represents the above (e3)).

[0019] As used herein, "active ester-forming group" means a chemical group that, together with the carbonyl group to which it is attached, forms an ester that activates the carbonyl group for coupling reactions with amino-containing compounds to form amide groups, or for other coupling reactions.

[0020] Examples of the active ester-forming group include groups obtained by removing a hydroxy group from a hydroxy compound 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-oxo-1,2,3-benzotriazine (HOOBt or HODhbt), N-hydroxy-5-norbornene-2,3-dicarboximide (HONB), 2,3,4,5,6-pentafluorophenol (HOPfp), or 6-chloro-1-hydroxy-1H-benzotriazole (Cl-HOBt) (see, for example, WATANABE Chemical catalog, Amino acids and chiral building blocks to new medicine; hereinafter, these are also collectively referred to as hydroxy compounds (Ae)). Among these, from the viewpoint of suitably obtaining the effects of the present invention, a group obtained by removing a hydroxy group from HOBt, HOAt, HOSu, or HOOBt is preferred, and a group obtained by removing a hydroxy group from HOBt, HOAt, or HOOBt is more preferred. Furthermore, when the active ester-forming group represents a group derived from HOSu, from the viewpoint of suitably obtaining the effects of the present invention, it is more preferred that E3 have two or more of the above-mentioned protected amino moieties.

[0021] The activated ester compound (e3) is synthesized, for example, from a carboxylic acid represented by "W-COOH" (W has the same meaning as the above (e3). Hereinafter, this may also be referred to as "carboxylic acid (W)") and the hydroxy compound (Ae). The organic group having 1 to 30 carbon atoms excluding the Boc group in W is preferably an organic group having 1 to 12 carbon atoms, more preferably an organic group having 1 to 6 carbon atoms. The carboxylic acid (W) has two or more Boc groups and does not contain *1-NH(Boc), *1-N(Boc) or *1-NH(Boc) in the molecule. ２ and "*1-N(Boc)-*1" (*1 represents a bond bonded to a carbon atom). The carboxylic acid (W) can be obtained by protecting the amino groups of a carboxy-containing polyamine (pA) having two or more amino groups, such as a carboxy-containing diamine. The amino groups may be protected in such a way that some or all of the amino groups of the amine are protected.

[0022] 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 typified by carboxydiphenyl ethers such as 4,4'-diaminodiphenylether-3-carboxylic acid or 4,4'-diaminodiphenylether-3-carboxylic acid; and aliphatic polyamines such as arginine, lysine, ornithine, or histidine.

[0023] From the viewpoint of suitably achieving the effects of the present invention, the carboxylic acid (W) and polyamine (pA) preferably have a nitrogen-containing heterocycle or a derivative thereof. Specific examples of the nitrogen-containing heterocycle include aziridine, azetidine, pyrrole, imidazole, imidazolidine, pyrrolidine, piperidine, piperazine, morpholine, pyrazole, indole, benzimidazole, and carbazole. Specific examples of derivatives of the nitrogen-containing heterocycle include compounds in which any hydrogen atom in the nitrogen-containing heterocycle is substituted with a substituent. Examples of the substituent include a linear or branched alkyl group having 1 to 4 carbon atoms, a linear or branched alkoxy group having 1 to 4 carbon atoms, a hydroxy group, a halogen atom, a nitro group, a cyano group, a trifluoromethyl group, -NR ７ R ８ , or -CONR ７ R ８ groups, and R ７ and R ８ each independently represents a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms.

[0024] Preferred specific examples of the active ester compound (e3) are any of the compounds represented by the following formulae (e3-1) to (e3-4).

[0025]

[0026] <Polyamic Acid (A)> (Structural Unit Derived from Tetracarboxylic Acid Derivative Contained in Polyamic Acid (A)) The polyamic acid (A) in the polymer (A) of the present invention contains, as a structural unit derived from a tetracarboxylic acid derivative, a structural unit represented by the above formula (1T ａ The polymer (A) may be composed of one or more types of structural units (a-1Ta), and the structural units (a-1Ta) may be composed of one or more types of structural units.

[0027] The above formula (1T ａ ) X ａ is a tetravalent organic group represented by the above formula (x-2) or a tetravalent organic group having an alicyclic structure of five or more members (T ５ａ ) represents

[0028] The tetravalent organic group (T ５ａ As the tetravalent organic group (T), a tetravalent organic group having a 5- to 8-membered alicyclic structure is preferred, and a tetravalent organic group having a 5- to 7-membered alicyclic structure is more preferred. Note that, when the alicyclic structure to which the acid anhydride group is bonded is a polycyclic structure, the alicyclic structure having 5 or more ring atoms means that the number of atoms constituting the ring in each ring contained in the polycyclic structure is 5 or more. Furthermore, the alicyclic structure may be bonded to at least one of the two acid anhydride groups, and may have a chain hydrocarbon structure or an aromatic ring structure together with the alicyclic structure. The tetravalent organic group (T ５ａ ) is preferably a compound represented by the following formula (X ５ａ -1) to (X ５ａ -18). ５ａ ) is, from the viewpoint of suitably obtaining the effects of the present invention, (X ５ａ -1) to (X ５ａ -4) is more preferable.

[0029]

[0030] From the viewpoint of suitably obtaining the effects of the present invention, the proportion of the structural unit (a-1Ta) contained in the polyamic acid (A) of the present invention is preferably more than 40 mol %, more preferably 50 mol % or more, relative to 1 mol of all structural units derived from tetracarboxylic acid derivatives contained in the polyamic acid (A).

[0031] The polyamic acid (A) of the present invention contains, as a structural unit derived from a tetracarboxylic acid derivative, a compound represented by the following formula (2T ａ The structural unit (2-1Ta) may be of one type or of two or more types. (X in the formula ２ａ is a tetravalent organic group represented by the above formula (x-2) and a tetravalent organic group having an alicyclic structure with five or more members (T ５ａ ) represents a tetravalent organic group derived from a tetracarboxylic dianhydride other than

[0032] The above formula (2T ａ ) in ２ａSpecific examples of the tetravalent organic group include tetravalent organic groups obtained by removing two acid anhydride groups from the following tetracarboxylic acid dianhydrides (hereinafter, these may be collectively referred to as "other tetracarboxylic acid dianhydrides").

[0033] acyclic aliphatic tetracarboxylic dianhydrides such as 1,2,3,4-butanetetracarboxylic dianhydride or tetracarboxylic dianhydrides represented by the following formulae (AL-1) to (AL-7); alicyclic tetracarboxylic dianhydrides such as tetracarboxylic dianhydrides having a tetravalent organic group represented by the following formula (x-1) (provided that the tetravalent organic group represented by the above formula (x-2) and the tetravalent organic group (T ５ａ ) excluding tetracarboxylic dianhydrides having the following structure: pyromellitic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 3,3',4,4'-diphenylsulfonetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3',4,4'-diphenylethertetracarboxylic dianhydride, 3,3',4,4'-perfluoroisopropylidenedi(phthalic anhydride), 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic dianhydride Aromatic tetracarboxylic acid dianhydrides such as hydrates, 4,4'-bis(3,4-dicarboxyphenoxy)-2,2-diphenylpropane dianhydride, ethylene glycol bisanhydrotrimellitate, 4,4'-(hexafluoroisopropylidene)diphthalic anhydride, 4,4'-carbonyldiphthalic anhydride, 4,4'-oxydi(1,4-phenylene)bis(phthalic)dianhydride, or 4,4'-methylenedi(1,4-phenylene)bis(phthalic)dianhydride; and also tetracarboxylic acid dianhydrides described in JP 2010-97188 A. (In formula (x-1), R １ ~R ４each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms and containing a fluorine atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 6 carbon atoms, an alkyloxycarbonyl group having 2 to 6 carbon atoms, or a phenyl group; R １ ~R ４ At least one of represents a group other than a hydrogen atom as defined above. * represents a bond.)

[0034] R in the above formula (x-1) １ ~R ４ Specific examples of the alkyl group having 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, in the above R include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a t-butyl group, and an n-pentyl group. １ ~R ４ Specific examples of the alkenyl group having 2 to 6 carbon atoms, preferably 2 to 4 carbon atoms, in the above R include a vinyl group, a propenyl group, and a butynyl group, which may be linear or branched. １ ~R ４ Specific examples of the alkynyl group having 2 to 6 carbon atoms, preferably 2 to 4 carbon atoms, in the above R include an ethynyl group, a 1-propynyl group, and a 2-propynyl group. １ ~R ４ In the formula (I), examples of the monovalent organic group containing a fluorine atom and having 1 to 6, preferably 1 to 4, carbon atoms include a fluoromethyl group, a trifluoromethyl group, a trifluoromethoxy group, a 2,2,2-trifluoroethyl group, a 2,2,2-trifluoroethoxy group, a pentafluoroethyl group, and a pentafluoropropyl group.

[0035] The above formula (x-1) is preferably one selected from the group consisting of the following formulae (x1-1) to (x1-5).

[0036]

[0037] More preferred examples of the other tetracarboxylic acid dianhydrides include 1,2,3,4-butanetetracarboxylic acid dianhydride, pyromellitic acid dianhydride, 3,3',4,4'-benzophenonetetracarboxylic acid dianhydride, 3,3',4,4'-diphenylsulfonetetracarboxylic acid dianhydride, 1,4,5,8-naphthalenetetracarboxylic acid dianhydride, 2,3,6,7-naphthalenetetracarboxylic acid dianhydride, 3,3',4,4'-diphenylethertetracarboxylic acid dianhydride, 3,3',4,4'-biphenyltetracarboxylic acid dianhydride, and 2,2',3,3'-biphenyltetracarboxylic acid dianhydride.

[0038] The polyamic acid (A) has the formula (2T ａ The proportion of the structural units represented by the formula (I) is preferably less than 60 mol %, more preferably 50 mol % or less, based on 1 mol of all structural units derived from tetracarboxylic acid derivatives contained in the polyamic acid (A).

[0039] The diamine-derived structural units contained in the polyamic acid (A) will be described in detail later.

[0040] <Polyamic Acid (B)> (Structural Unit Derived from Tetracarboxylic Acid Derivative Contained in Polyamic Acid (B)) One embodiment of the liquid crystal aligning agent of the present invention is a polyamic acid (B) having, together with the polyamic acid (A), a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, wherein the structural unit derived from the tetracarboxylic acid derivative is a structural unit represented by the formula (1T ｂ The polyamic acid (B) may be composed of one or more types of structural units. The polyamic acid (B) may be composed of one or more types of structural units.

[0041] The above formula (1T ｂ ) X ｂExamples of the tetravalent organic group that gives the formula include a tetravalent organic group obtained by removing two anhydride groups (-C(=O)-O-C(=O)-) from an aromatic tetracarboxylic dianhydride. Here, the aromatic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups, including at least one carboxy group bonded to an aromatic ring. From the viewpoint of preferably obtaining the effects of the present invention, the above X ｂ The tetravalent organic group derived from an aromatic tetracarboxylic dianhydride in X is preferably a tetracarboxylic dianhydride having a benzene ring. ｂ The tetravalent organic group derived from the aromatic tetracarboxylic dianhydride in the formula (2T ａ ) in ２ａ It is a tetravalent organic group obtained by removing two anhydride groups from the aromatic tetracarboxylic dianhydride exemplified above.

[0042] From the viewpoint of suitably obtaining the effects of the present invention, the proportion of the structural unit (b-1Tb) contained in the polyamic acid (B) is preferably 60 mol % or more, and more preferably 70 mol % or more, relative to 1 mol of all structural units derived from tetracarboxylic acid derivatives contained in the polyamic acid (B).

[0043] The polyamic acid (B) of the present invention contains, as a structural unit derived from a tetracarboxylic acid derivative, a compound represented by the following formula (2T ｂ ) may have a structural unit (b-2Tb) represented by the formula (b-2Tb). (X in the formula ２ｂ is X ｂ represents a tetravalent organic group other than

[0044] The above formula (2T ｂ ) in ２ｂSpecific examples of the tetravalent organic group include a tetravalent organic group obtained by removing two anhydride groups from an acyclic aliphatic tetracarboxylic acid dianhydride, or a tetravalent organic group obtained by removing two anhydride groups from an alicyclic tetracarboxylic acid dianhydride. Here, the acyclic aliphatic tetracarboxylic acid dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups bonded to a chain hydrocarbon structure. However, it does not have to be composed solely of a chain hydrocarbon structure, and it may partially contain an alicyclic structure or an aromatic ring structure. The alicyclic tetracarboxylic acid dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups, including at least one carboxy group bonded to the alicyclic structure. However, none of these four carboxy groups are bonded to an aromatic ring. Furthermore, it does not have to be composed solely of an alicyclic structure, and it may partially contain a chain hydrocarbon structure or an aromatic ring structure. More preferred X ２ｂ represents a tetravalent organic group obtained by removing two anhydride groups from the acyclic aliphatic tetracarboxylic dianhydrides exemplified above as other tetracarboxylic dianhydrides, a tetravalent organic group represented by the above formula (x-1), a tetravalent organic group represented by the above formula (x-2), or the above tetravalent organic group (T ５ａ ) are listed.

[0045] From the viewpoint of suitably obtaining the effects of the present invention, the proportion of the structural unit (b-2Tb) contained in the polyamic acid (B) is preferably 40 mol % or less, and more preferably 30 mol % or less, relative to 1 mol of all structural units derived from tetracarboxylic acid derivatives contained in the polyamic acid (B).

[0046] The diamine-derived structural units contained in the polyamic acid (B) will be described in detail later.

[0047] (Diamine-derived structural units contained in polyamic acid (A) and polyamic acid (B)) The polyamic acid (A) in the polymer (A) of the present invention contains, as a diamine-derived structural unit, a structural unit represented by the above formula (1D ａ The structural unit (a-1Da) is represented by the structural unit (a-1D ａ ) may be one type or two or more types.

[0048] The above formula (1D ａIn the above formula, the monovalent organic group represented by Z is a monovalent hydrocarbon group having 1 to 6 carbon atoms, and a methylene group of the hydrocarbon group may be substituted with -O-, -S-, -CO-, -COO-, -COS-, -NR ３ --CO-NR ３ -, -Si(R ３ ) ２ - (However, R ３ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbon atoms. ３ If there are two, R ３ may be the same or different from each other, —SO ２ - or the like; a monovalent group in which at least one hydrogen atom bonded to a carbon atom of the monovalent hydrocarbon group or the monovalent group A is substituted with a halogen atom, a hydroxy group, an alkoxy group, a nitro group, an amino group, a mercapto group, a nitroso group, an alkylsilyl group, an alkoxysilyl group, a silanol group, a sulfino group, a phosphino group, a carboxy group, a cyano group, a sulfo group, an acyl group, or the like; and a monovalent group having a heterocycle. ａ As the monovalent organic group for Z in the above formula (1D), an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, or a t-butoxycarbonyl group is preferred, an alkyl group having 1 to 3 carbon atoms is more preferred, and a methyl group is even more preferred. ａ In order to preferably obtain the effects of the present invention, two Z's in the formula (I) are each independently preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom or a methyl group.

[0049] The above formula (1D ａ ) in Y ａ Specific examples of the divalent organic group include divalent organic groups derived from the above-mentioned diamine (0) or other diamines described below.

[0050] The polyamic acid (B) in the polymer (B) of the present invention contains, as a diamine-derived structural unit, a structural unit represented by the above formula (1D ｂ The structural unit (b-1Db) may be of one type or of two or more types. ｂThe monovalent organic group of Z in the formula (1D ａ ) is synonymous with Z.

[0051] The above formula (1D ｂ ) Y ｂ In the diamine (0) in １ , Ar １’ each independently represents a benzene ring, a biphenyl structure, or a naphthalene ring. １ , Ar １’ Any hydrogen atom on the ring may be substituted with a monovalent group. A represents a divalent organic group having an alkylene structure and having 1 to 10 carbon atoms. L １ , L １’ each independently represents a single bond, —O—, —S—, —C(═O)—, —O—C(═O)—, —NR— (R represents a hydrogen atom or a monovalent organic group), —C(═O)—NR— (R represents a hydrogen atom or a monovalent organic group), or —NR—C(═O)— (R represents a hydrogen atom or a monovalent organic group).

[0052] (Diamine (0)) L of the above diamine (0) １ , L １’ Examples of the monovalent organic group for R in -NR-, -C(=O)-NR-, or -NR-C(=O)- represent an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, an alkenyl group having 2 to 3 carbon atoms, an acyl group having 2 to 3 carbon atoms, an alkylsilyl group having 1 to 3 carbon atoms, an alkoxysilyl group having 1 to 3 carbon atoms, a Boc group, or a monovalent organic group in which at least a portion of the hydrogen atoms in these groups have been substituted with at least either a halogen atom or a hydroxy group.

[0053] Ar of the diamine (0) １ and Ar １’Examples of the monovalent group that is a substituent for any hydrogen atom on the ring include monovalent groups such as a halogen atom; an alkyl group having 1 to 3 carbon atoms; an alkyl group having 1 to 3 carbon atoms in which at least a portion of the hydrogen atoms is substituted with a halogen atom or a hydroxy group; an alkoxy group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms in which at least a portion of the hydrogen atoms is substituted with at least one of the above halogen atoms and a hydroxy group; an alkenyl group having 2 to 3 carbon atoms; an acyl group having 2 to 3 carbon atoms; an alkylsilyl group having 1 to 3 carbon atoms; an alkoxysilyl group having 1 to 3 carbon atoms; a hydroxy group, and a nitrile group.

[0054] Ar of the diamine (0) １ and Ar １’Specific examples of the alkyl group include 1,4-phenylene, 1,3-phenylene, 2-methyl-1,4-phenylene, 2-ethyl-1,4-phenylene, 2-propyl-1,4-phenylene, 2-butyl-1,4-phenylene, 2-isopropyl-1,4-phenylene, 2-t-butyl-1,4-phenylene, 2-methoxy-1,4-phenylene, 2-ethoxy-1,4-phenylene, 2-propoxy-1,4-phenylene, 2-butoxy-1,4-phenylene, and 2-fluoro-1,4 a benzene ring which may have a substituent such as 4,4'-biphenylylene, 2-methyl-4,4'-biphenylylene, 2-ethyl-4,4'-biphenylylene, 2-propyl-4,4'-biphenylylene, 2-butyl-4,4'-biphenylylene, 2- t-butyl-4,4'-biphenylylene, 2-methoxy-4,4'-biphenylylene, 2-ethoxy-4,4'-biphenylylene, 2-fluoro-4,4'-biphenylylene, 3-methyl-4,4'-biphenylylene, 3-ethyl-4,4'-biphenylylene, 3-propyl-4,4'-biphenylylene, 3-butyl-4,4'-biphenylylene, 3-t-butyl-4,4'-biphenylylene, 3-methoxy-4,4'-biphenylylene, 3-ethoxy-4,4'-biphenylylene biphenyl structures which may have a substituent such as phenylylene, 3-fluoro-4,4'-biphenylylene, 2,2'-dimethyl-4,4'-biphenylylene, 3,3'-dimethyl-4,4'-biphenylylene, 3,3'-biphenylylene, 5-methyl-3,3'-biphenylylene, and 5,5'-dimethyl-3,3'-biphenylylene; and naphthalene rings which may have a substituent such as 1,5-naphthylene, 2,6-naphthylene, and 1-methyl-2,6-naphthylene.

[0055] In the diamine (0), A is a divalent organic group having 1 to 10 carbon atoms and an alkylene structure. When the alkylene structure has three or more carbon-carbon bonds, any carbon-carbon bond constituting the alkylene structure may be replaced with a carbon-carbon double bond. A is preferably an alkylene group (q0) having 1 to 10 carbon atoms; a divalent organic group (q1) obtained by inserting —O—, —C(═O)—, —NH—, —O—C(═O)—, —C(═O)—O—, —NR—C(═O)—, —C(═O)—NR—, or —NR— (wherein R represents a monovalent organic group) between the carbon-carbon bonds of the alkylene group; or a divalent organic group (q2) having at least one —NR—C(═O)—NR— (wherein R represents a hydrogen atom or a monovalent organic group) between the carbon-carbon bonds of the alkylene group. Here, the monovalent organic group of R in the above-mentioned —NR—C(═O)—NR— is L of the above-mentioned diamine (0). １ and L １’ Examples of the structure include the structures exemplified for R in —C(═O)—NR—, which represents:

[0056] Preferred examples of (q0), (q1), and (q2) are as follows: *—(CH ２ ) ｎ - *, * - (CH ２ ) ｎ１ -O-(CH ２ ) ｎ２ - *, * - (CH ２ ) ｎ１ -NR-(CH ２ ) ｎ２ -*, *-(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 -*, *-(CH ２ ) ｍ１ -C(=O)-NR-(CH ２ ) ｎ’-NR-C(=O)-(CH ２ ) ｍ２ -*, *-(CH ２ ) ｍ１ -NR-C(=O)- (CH ２ ) ｎ’ -C(=O)-NR-(CH ２ ) ｍ２ - *, * - (CH ２ ) ｎ１ -NR-C(=O)-NR-(CH ２ ) ｎ２ -*

[0057] In the above chemical formula, R represents a hydrogen atom or a monovalent organic group. The monovalent organic group is, for example, L of the diamine (0). １ and L １’ Examples of the structures include those exemplified for R in -C(=O)-NR-, which represents the formula: *-(CH ２ ) ｎ１ -O-(CH ２ ) ｎ２ In -*, n1 and n2 are each independently an integer of 1 to 6, and the sum of n1 and n2 is 2 to 10. *-(CH ２ ) ｎ１ -NR-C(=O)-NR-(CH ２ ) ｎ２ -In *, n1 and n2 are each independently an integer of 1 to 6, and the sum of n1 and n2 is 2 to 9.

[0058] *-L １ -A-L １’ From the viewpoint of suitably obtaining the effects of the present invention, the following embodiments are preferred for -*. In the following formulae, the definitions of m1, m2, n, n', n1, and n2 are the same as in the formulae above. Furthermore, in the following formulae, R represents a hydrogen atom or a monovalent organic group. When two Rs are present, they each independently have the above definition. As the monovalent organic group, L of the diamine (0) is preferred. １ and L １’Examples of structures include those exemplified for R in —C(═O)—NR—, which represents ２ ) ｎ -*, -O-(CH ２ ) ｎ -O-*, *-NR-(CH ２ ) ｎ -NR-*, *-O-(CH ２ ) ｎ１ -O-(CH ２ ) ｎ２ -O-*, *-O-(CH ２ ) ｎ１ -NR-(CH ２ ) ｎ２ -O-*, *-C(=O)-(CH ２ ) ｎ -C(=O)-*, *-C(=O)-NR-(CH ２ ) ｎ -O-*, *-OC(=O)-(CH ２ ) ｎ -O-*, *-OC(=O)-(CH ２ ) ｎ -OC(=O)-*, *-OC(=O)-(CH ２ ) ｎ -C(=O)-O-*, *-(CH ２ ) ｍ１ -OC(=O)-(CH ２ ) ｎ’ -C(=O)-O-(CH ２ ) ｍ２ -* *-S-(CH ２ ) ｎ -S-*, *-C(=O)-NR-(CH ２ ) ｎ -NR-C(=O)-*, *-C(=O)-O-(CH ２ ) ｎ -OC(=O)-*, *-(CH ２ ) ｍ１ -C(=O)-O-(CH ２ ) ｎ’ -OC(=O)-(CH ２ ) ｍ２ -* *-O-(CH ２ ) ｎ -*, *-S-(CH ２ )ｎ -*, *-NR-C(=O)-(CH ２ ) ｎ -C(=O)-NR-* *-(CH ２ ) ｍ１ -C(=O)-NR-(CH ２ ) ｎ’ -NR-C(=O)-(CH ２ ) ｍ２ -*, *-(CH ２ ) ｍ１ -NR-C(=O)- (CH ２ ) ｎ’ -C(=O)-NR-(CH ２ ) ｍ２ - *, * - (CH ２ ) ｎ１ -NR-C(=O)-NR-(CH ２ ) ｎ２ -* Furthermore, from the viewpoint of preferably obtaining the effects of the present invention, *-(CH ２ ) ｎ -*, *-O-(CH ２ ) ｎ -O-*, *-O-(CH ２ ) ｎ - * is preferred.

[0059] In order to preferably obtain the effects of the present invention, the structural unit (b-1Db) is a divalent organic group represented by any one of the following formulae (h1-1) to (h1-22), or a divalent organic group represented by the formula (d Ｄａ Preferably, the diamine has a divalent organic group obtained by removing two amino groups from a diamine represented by formula (Am-1), or a divalent organic group obtained by removing two amino groups from a diamine represented by formula (Am-1) to (Am-2) described later. In formulas (h1-1) to (h1-22), the bonding positions of the benzene ring are preferably the 1st and 4th positions, and the bonding positions of the naphthalene ring are preferably the 2nd and 6th positions. In formulas (h1-4) and (h1-17), -CH ２ The total number of - is 10 or less. In formulae (h1-7), (h1-8), and (h1-14), -CH ２The total number of - is 8 or less, and two m's may be the same or different. In addition, the hydrogen atoms on the benzene rings of the following formulae (h1-1) to (h1-22) may be substituted with a methyl group, a methoxy group, or a fluorine atom.

[0060] (Diamine (0')) Diamine (0'), "H-N(Z)-Ar ２ -L ２ -A ２ -L ２’ -Ar ２’ Ar is a diamine represented by the formula "-N(Z)-H". ２ and Ar ２’ each independently represents a benzene ring, a biphenyl structure, a naphthalene ring, or an aromatic heterocycle. ２ and Ar ２’ Any hydrogen atom on the ring of Ar １ , Ar １’ may be substituted with a monovalent group exemplified by A ２ represents a divalent organic group having an alkylene group. ２ , L ２’ are each independently a single bond, -O-, -S-, -C(=O)-, -O-C(=O)-, -NR- (R represents a hydrogen atom or a monovalent organic group), -C(=O)-NR- (R represents a hydrogen atom or a monovalent organic group), or -NR-C(=O)- (R represents a hydrogen atom or a monovalent organic group). ２ and Ar ２’ and A ２Any one of the above has a heterocycle. Examples of the heterocycle include a pyrrole ring, an imidazole ring, a pyrazole ring, a triazole ring, a pyridine ring, a pyrimidine ring, a pyridazine ring, a pyrazine ring, an indole ring, a benzimidazole ring, a purine ring, a quinoline ring, an isoquinoline ring, a naphthyridine ring, a quinoxaline ring, a phthalazine ring, a triazine ring, a carbazole ring, an acridine ring, a piperidine ring, a piperazine ring, a pyrrolidine ring, and a hexamethyleneimine ring. Among these, a pyridine ring, a pyrimidine ring, a pyrazine ring, a benzimidazole ring, a piperidine ring, a piperazine ring, a quinoline ring, a carbazole ring, an indoline ring, a 1,7-dihydroimidazo[4,5-f]benzimidazole skeleton, or an acridine ring is preferred. More preferred specific examples of diamine (0') include the following (d Ｄａ -8), 4-[4-[(4-aminophenoxy)methyl]-4,5-dihydro-4-methyl-2-oxazolyl]-benzenamine, 4-[4-[(4-aminophenoxy)methyl]-4,5-dihydro-2-oxazolyl]-benzenamine, or the following (d Ｈｔ -1) to (d Ｈｔ d-8) Ｈｔ -6, d Ｈｔ -8 is preferably 1,4-bis(p-aminobenzyl)piperazine, 4,4'-[4,4'-propane-1,3-diylbis(piperidine-1,4-diyl)]dianiline.

[0061] The polyamic acid (B) has a structural unit derived from a diamine represented by the following formula (2D ｂ ) may have a structural unit (b-2Db) represented by the formula (b-2Db). (Y in the formula ２ｂ represents a divalent organic group derived from a diamine other than diamine (0) and diamine (0′) (hereinafter also referred to as other diamines). Z represents a divalent organic group derived from a diamine other than diamine (0) and diamine (0′) (hereinafter also referred to as other diamines). ａ ) is synonymous with Z in

[0062] Examples of other diamines in the structural unit (b-2Db) derived from other diamines include 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-methoxybenzene, 2,5-diaminotoluene, 2,6-diaminotoluene, 4-aminobenzylamine, 2-(4-aminophenyl)ethylamine, semi-aromatic diamines having a secondary amino group and a primary amino group (preferably and 4-(2-(methylamino)ethyl)aniline.) (Here, semi-aromatic diamine refers to a diamine in which one amino group is bonded to an aromatic ring and the other amino group is not bonded to an aromatic ring.), 4-(2-aminoethyl)aniline, 2-(6-aminonaphthyl)ethylamine, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diamino Biphenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl, 3-trifluoromethyl-4,4'-diaminobiphenyl, 2-trifluoromethyl-4,4'-diaminobiphenyl, 3-fluoro-4,4'-diaminobiphenyl, 2-fluoro-4,4'-diaminobiphenyl, 2,2'-difluoro-4,4'-diaminobiphenyl, 3,3'-difluoro-4,4'-diaminobiphenyl, 2,2'-bis(trifluoromethyl)-4,4 '-diaminobiphenyl, 3,3'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 4,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,2'-diaminobiphenyl, 2,3'-diaminobiphenyl, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 2,5-diaminonaphthalene, 2,6-diaminonaphthalene, 2,7-diaminonaphthalene;

[0063] 1,4-phenylenebis(4-aminobenzoate), 1,4-phenylenebis(3-aminobenzoate), 1,3-phenylenebis(4-aminobenzoate), 1,3-phenylenebis(3-aminobenzoate), bis(4-aminophenyl)terephthalate, bis(3-aminophenyl)terephthalate, bis(4-aminophenyl)isophthalate, bis(3-aminophenyl)isophthalate; diamines having a photoalignment group such as 4,4'-diaminoazobenzene, diaminotolan, diamines represented by the following formulas (D-1) to (D-5), or aromatic diamines having a cinnamate structure typified by 4,4-diaminochalcone; 4,4'-diaminobenzanilide, diamines represented by the following formula (D-6), diamines having an amide bond such as (Am-3) to (Am-6); diamines having a urea bond such as 1,3-bis(4-aminophenyl)urea; H ２ New York Ｄ -NH ２ (Y Ｄ represents a divalent organic group having, in the molecule, -N(D)- (D represents a protecting group which is eliminated by heating and replaced with a hydrogen atom); diamines having a thermally eliminable group such as

[0064] 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 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, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 4,4'-sulfonyldianiline, 3,3'-sulfonyldianiline, bis(4-aminophenyl)silane, bis(3-aminophenyl)silane, dimethyl-bis(4-aminophenyl)silane, dimethyl-bis(3-aminophenyl) ) silane, 4,4'-thiodianiline, 3,3'-thiodianiline, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis(4-aminophenyl)hexafluoropropane, 2,2-bis(3-aminophenyl)hexafluoropropane, 2,2-bis(3-amino-4-methylphenyl)hexafluoropropane, 2,2-bis(4-aminophenyl)propane, 2,2-bis(3-aminophenyl)propane, 2,2-bis(3-amino-4-methylphenyl)propane, 4,4'-diaminobenzophenone, 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, 2,5-bis(4- 4,4'-(1-methyl-1H-pyrrole-2,5-diyl)bis[benzenamine], 1,4-bis-(4-aminophenyl)-piperazine, 2-N-(4-aminophenyl)pyridine-2,5-diamine, 2-N-(5-aminopyridin-2-yl)pyridine-2,5-diamine, 2-(4-aminophenyl)-5-aminobenzimidazole, 2-(4-aminophenyl)-6-aminobenzimidazole, 5-(1H-benzyl heterocycle-containing diamines such as 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- diamines having at least one nitrogen atom-containing structure selected from the group consisting of a nitrogen atom-containing heterocycle and a secondary or tertiary amino group, typified by diamines having a diphenylamine structure such as benzenediamine (excluding amino groups derived from -N(D)- (D represents a protecting group which is eliminated by heating and replaced with a hydrogen atom); hereinafter, this is also referred to as a specific nitrogen atom-containing structure, and the specific nitrogen atom-containing structure is an atomic group other than the two amino groups which participate in the polycondensation reaction);

[0065] 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, 4,4'-diaminodiphenylethane-3-carboxylic acid, 4,4'-diaminobiphenyl-3,3'-dicarboxylic acid, 4,4'-diaminobiphenyl-2,2'-dicarboxylic acid, 3,3'-diaminobiphenyl-4,4'-dicarboxylic acid, 3,3'-diaminobiphenyl-2,4'-dicarboxylic acid, 4,4'-diaminodiphenylmethane-3,3'-dicarboxylic acid, 4, Diamines having a carboxy group such as 4'-diaminodiphenylethane-3,3'-dicarboxylic acid and 4,4'-diaminodiphenylether-3,3'-dicarboxylic acid; 1-(4-aminophenyl)-1,3,3-trimethyl-1H-indan-5-amine and 1-(4-aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H-indene-6-amine; diamines having a siloxane bond such as 1,3-bis(3-aminopropyl)-tetramethyldisiloxane; acyclic aliphatic diamines such as metaxylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, and hexamethylenediamine; alicyclic diamines such as 1,3-bis(aminomethyl)cyclohexane, 1,4-diaminocyclohexane, and 4,4'-methylenebis(cyclohexylamine).

[0066] (In formula (z-2), two m's each independently have the above definition.) (X in (z-13) １３ represents a methyl group or a phenyl group. (In formula (z-19), X １９ represents —C(═O)—, —O—, or —NH—. １９ , R １９’each independently represents a hydrogen atom or a methyl group. ２２ is -CH ２ -, -(CH ２ ) ３ - or -NH-.)

[0067] D in -N(D)- contained in the other diamines is preferably a carbamate-based organic group typified by a benzyloxycarbonyl group, a 9-fluorenylmethyloxycarbonyl group, an allyloxycarbonyl group, a Boc group, etc. A Boc group is particularly preferred from the viewpoints that it is efficiently eliminated by heat, is eliminated at a relatively low temperature, and is discharged as a harmless gas upon elimination.

[0068] Preferable examples of the diamines having a thermally detachable group exemplified as the other diamines include those represented by the following formula (d Ｄａ -1) to (d Ｄａ Among them, diamines selected from the following formula (d Ｄａ -2) to (d Ｄａ -7), (d Ｄａ -9) to (d Ｄａ Diamines selected from (d-10) are more preferred. Ｄａ -3) to (d Ｄａ -5) The total number of carbon atoms in the linking groups that link the benzene rings is 11 or more. (Formula (d Ｄａ −2), (d Ｄａ -6), (d Ｄａ -7) In the formula, R represents a hydrogen atom or a Boc group.

[0069] In one embodiment, the proportion of the structural unit (b-1Db) contained in the polyamic acid (B) is preferably 5 mol % or more, more preferably 10 mol % or more, and even more preferably 20 mol % or more, relative to 1 mol of all diamine-derived structural units contained in the polyamic acid (B). Furthermore, the proportion of the structural unit (b-1Db) contained in the polyamic acid (B) may be 100 mol %, 95 mol % or less, or 90 mol % or less, relative to 1 mol of all diamine-derived structural units contained in the polyamic acid (B).

[0070] In one embodiment, in the polyamic acid (A), the Y ａ The polyamic acid (A) may contain 5 mol % or more, 10 mol % or more, or 20 mol % or more of the structural unit (a-1Da) in which Y is a divalent organic group derived from the diamine (0) relative to 1 mol of all the structural units derived from the diamine contained in the polyamic acid (A). ａ The polyamic acid (A) may contain 100 mol %, 95 mol % or less, or 90 mol % or less of the structural unit (a-1Da), in which the structural unit (a-1Da) is a divalent organic group derived from the diamine (0), relative to 1 mol of all the structural units derived from the diamine contained in the polyamic acid (A).

[0071] In one embodiment, when the polyamic acid (B) has the structural unit (b-2Db), Y of the structural unit (b-2Db) is preferably 0.01 to 0.01, from the viewpoint of exhibiting a low pretilt angle. ２ｂmay have a diphenyl ether skeleton. Preferred examples of diamines that provide a diphenyl ether skeleton include diamines having a diphenyl ether skeleton among the compounds exemplified above as other diamines (preferably 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 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, or 1,4-bis[4-(4-aminophenoxy)phenoxy]benzene). Furthermore, from the viewpoint of improving the two-phase separation between the two types of polymers, the polyamic acid (A) and / or the polyamic acid (B) may contain, as a diamine-derived structural unit, a structural unit derived from the diamine having the above-mentioned thermally detachable group. The proportion of the structural units derived from the diamine having the thermally detachable group is preferably 5 to 40 mol %, more preferably 5 to 35 mol %, and even more preferably 5 to 30 mol %, relative to 1 mol of all structural units derived from diamine contained in the polyamic acid (A) and / or polyamic acid (B). Furthermore, in order to suitably obtain the effects of the present invention, it is preferable that the diamines in the structural units derived from diamine in the polyamic acid (A) and / or polyamic acid (B), other than the diamine having the thermally detachable group, are diamines that do not have a side chain group having 3 or more carbon atoms.

[0072] The polyamic acid (A) and / or the polyamic acid (B) are selected from the group consisting of the above-mentioned Y and the polyamic acid (B) in view of the small afterimage caused by the residual DC. ａ , and / or Y ２ｂis preferably a divalent organic group obtained by removing two amino groups from a diamine having a urea bond (for example, a diamine (0) in which A is a divalent organic group (q2), or a diamine having a urea bond exemplified in the above-mentioned other diamines), a diamine having an amide bond, a diamine having the above-mentioned specific nitrogen atom-containing structure, a diamine having a carboxy group, or a diamine selected from the group consisting of 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, p-phenylenediamine, and m-phenylenediamine (these are also collectively referred to as specific divalent organic group (b)).

[0073] The polyamic acid (A) and / or the polyamic acid (B) are selected from the group consisting of the above-mentioned Y and the polyamic acid (B) in view of the small afterimage caused by the residual DC. ａ is the specific divalent organic group (b) of the formula (1D ｂ ) and / or the structural unit (a-1Da) represented by the above Y ２ｂ is the specific divalent organic group (b) of the formula (2D ｂ ) may be contained in an amount of 5 mol % or more, preferably 10 mol % or more, and more preferably 20 mol % or more, relative to 1 mol of all structural units derived from diamine contained in the polyamic acid (A) and / or the polyamic acid (B).

[0074] The above formula (1D ｂ ) and (2D ｂ As the monovalent organic group of Z in the above formula (1D ａ ) and Z in the above formula (I) are examples of the structures shown above.

[0075] One embodiment of the liquid crystal aligning agent of the present invention includes, but is not limited to, the following embodiments (BL1) to (BL2): In the polyamic acid (B), the structural unit (b-1Db) is contained in an amount of 5 mol % or more relative to 1 mol of all structural units derived from diamines contained in the polyamic acid (B), and in the polyamic acid (A), Y ａ is the specific divalent organic group (b) of the formula (1D ａAspect (BL1): The polyamic acid (B) contains structural units (b-1Db) in an amount of 5 mol % or more relative to 1 mol of all diamine-derived structural units contained in the polyamic acid (B), and in the polyamic acid (A), Y ａ is the specific divalent organic group (b) of the formula (1D ａ The polyamic acid (A) contains 10 to 95 mol % of structural units (a-1Da) represented by the formula: Y ａ is a divalent organic group other than the specific divalent organic group (b) of the formula (1D ａ ) is contained in an amount of 5 to 90 mol % relative to 1 mol of all structural units derived from diamine contained in the polyamic acid (A).

[0076] In the liquid crystal aligning agent of the present invention, from the viewpoint of the effects of the present invention, particularly, of reducing afterimages caused by residual DC, the content ratio of the polyamic acid (A) to the polyamic acid (B) may be 10 / 90 to 90 / 10, 20 / 80 to 90 / 10, or 20 / 80 to 80 / 20, in terms of the mass ratio of [polyamic acid (A) / polyamic acid (B)].

[0077] <Polyamic Acid (B')> The structural unit derived from a tetracarboxylic acid derivative contained in the polyamic acid (B') is a structural unit derived from a tetracarboxylic acid derivative contained in the polyamic acid (B') represented by the above formula (1T ａ The polyamic acid (B') has the same structural unit derived from a tetracarboxylic acid derivative as the polyamic acid (B), including preferred embodiments, except that the polyamic acid (B') does not contain the structural unit (a-1Da) represented by the formula (1D ｂ’The polyamic acid (B) may contain a structural unit (b-1Db') derived from a diamine, which is the same as the diamine-derived structural unit contained in the polyamic acid (B), including preferred embodiments, except that the polyamic acid (B') may contain a structural unit derived from the other diamine as a diamine-derived structural unit. When the polyamic acid (B') contains a structural unit derived from the other diamine, the structural unit does not include the structural unit (b-1Db'). Furthermore, in the liquid crystal aligning agent of the present invention, from the viewpoint of achieving the effects of the present invention, particularly reducing afterimages derived from residual DC, the content ratio of the polyamic acid (B) to the polyamic acid (B') may be, in terms of a mass ratio of [polyamic acid (B') / polyamic acid (B)], from 10 / 90 to 90 / 10, from 20 / 80 to 90 / 10, or from 20 / 80 to 80 / 20.

[0078] (Structural unit (b-1Db')) The polyamic acid (B') is represented by the following formula (1D ｂ’ ) may contain a structural unit (b-1Db') represented by the formula (b-1Db'). (Formula (1D ｂ’ ) in Y ｂ’ is a diamine (1) "H-N(Z)-Ar ３ represents a divalent organic group derived from the group consisting of Ar, Ar(Z), ... ３ is -Ar ４ -NR １ -Ar ４’ -, -Ar ４１ -Ar ４２ -, or three or more cyclic groups selected from the group consisting of a benzene ring and a heterocycle are directly or ２ The divalent organic group is bonded to two -N(Z)- groups via aromatic carbon atoms contained in a benzene ring or a heterocycle, and the two aromatic carbon atoms are not contained in the same cyclic group. ４ and Ar ４’ each represents a benzene ring or an aromatic heterocycle. ４１ and Ar ４２ each represents a benzene ring or an aromatic heterocycle, and Ar ４１ and Ar ４２ One of Ar represents a benzene ring, and the other represents an aromatic heterocycle. ３Any hydrogen atom on the benzene ring or aromatic heterocycle of Ar １ , Ar １’ may be substituted with a monovalent group exemplified by —NR １ -, -NR ２ R in - １ , R ２ , represents a hydrogen atom or a monovalent organic group. １ -, -NR ２ R in - １ , R ２ Specific examples of the monovalent organic group include the specific examples of the monovalent organic group exemplified as -NR- in diamine (0). ３ Specific examples of the heterocycle and aromatic heterocycle in the above formula include Ar ２ and Ar ２’ and A ２ Specific preferred examples of the diamine (1) include 1,4-bis-(4-aminophenyl)-piperazine, 1,4-bis-(4-aminophenyl)-piperazine, 2-N-(4-aminophenyl)pyridine-2,5-diamine, 2-N-(5-aminopyridin-2-yl)pyridine-2,5-diamine, 2-(4-aminophenyl)-5-aminobenzimidazole, 2-(4-aminophenyl)-6-aminobenzimidazole, 5-(1H-benzimidazol-2-yl)benzene-1,3-diamine, diamines represented by formulas (z-3) to (z-12), diamines represented by formulas (z-14) to (z-15), and diamines represented by formulas (z-17) to (z-19) (wherein X １９ represents —NH—, and R １９ , R １９ represents a hydrogen atom or a methyl group), a diamine represented by formula (z-22) (X ２２ represents —NH—.) Examples thereof include 4,4′-diaminodiphenylamine, 4,4′-diaminodiphenyl-N-methylamine, N,N′-bis(4-aminophenyl)-benzidine, N,N′-bis(4-aminophenyl)-N,N′-dimethylbenzidine, and N,N′-bis(4-aminophenyl)-N,N′-dimethyl-1,4-benzenediamine.

[0079] <Production of Polyamic Acid> The polyamic acid contained in the liquid crystal aligning agent of the present invention can be produced, for example, by the following method. A polymer having an amic acid structure (polyamic acid) is obtained by reacting a tetracarboxylic dianhydride component, a diamine component, and an amino terminal modifier added as needed. The polyamic acid is a polymer having an amic acid structure represented by the above formula (1D ａ When the diamine component has a structure represented by the formula -N(Z)-Y ａ The structure of -N(Z)- (Y ａ , Z is defined as above.) is used, and as the tetracarboxylic acid derivative component, a diamine having X ａ (X ａ The definitions of are the same as above.) is used.

[0080] The ratio of tetracarboxylic dianhydride and diamine used in the production of polyamic acid is preferably 0.5 to 2 equivalents of the acid anhydride group of the tetracarboxylic dianhydride per equivalent of the amino group of the diamine, more preferably 0.8 to 1.2 equivalents. As with conventional polycondensation reactions, the closer the equivalent of the acid anhydride group of the tetracarboxylic dianhydride is to 1 equivalent, the higher the molecular weight of the resulting polyamic acid. The reaction temperature in the production of polyamic acid is preferably -20 to 150°C, more preferably 0 to 100°C. The reaction time is preferably 0.1 to 24 hours, more preferably 0.5 to 12 hours. The production of polyamic acid can be carried out at any concentration, but preferably 1 to 50% by mass, more preferably 5 to 30% by mass. The reaction can be carried out at a high concentration initially, with subsequent addition of solvent.

[0081] At least some of the terminals of the polyamic acid (B) contain the non-amino group. At least some of the terminals of the polyamic acid (A) may contain the non-amino group. The non-amino group can be formed, for example, using an amino terminal modifier. Preferred examples of the amino terminal modification include the acyclic aliphatic dicarboxylic acid anhydrides, compound (e2-1), compound (e2-2), or active ester compound (e3). The polyamic acid (A) and / or polyamic acid (B) can be obtained, for example, by the following production method (a), production method (b), or a method using both. Production method (a): A method of polymerizing (polycondensing) a tetracarboxylic dianhydride component, a diamine component, and an amino terminal modifier. Production method (b): A method of reacting a tetracarboxylic dianhydride component with a diamine component to obtain a polymer solution containing a polyamic acid with unmodified amino terminals, and then adding an amino terminal modifier to the polymer solution to react the polymer terminals. In the above-mentioned production method (b), to obtain an amino-terminated polyamic acid, the ratio of the diamine to the tetracarboxylic dianhydride used in the production of the polyamic acid need only be equal to or greater than the ratio of the tetracarboxylic dianhydride. Preferably, the acid anhydride group of the tetracarboxylic dianhydride is 0.5 to 1.0 equivalents per equivalent of the amino group of the diamine, more preferably 0.8 to 1.0 equivalents. The ratio of the amino terminal modifier used is preferably 40 molar parts or less, more preferably 30 molar parts or less, per 100 molar parts of the total diamine components used. Furthermore, the ratio of the amino terminal modifier used is preferably 0.1 molar parts or more, more preferably 0.2 molar parts or more, per 100 molar parts of the total diamine components used. The temperature during the reaction of the amino terminal modifier with the polyamic acid may be the same as the reaction temperature used in the production of the polyamic acid, or the reaction may be carried out while heating. The heating temperature is preferably 30 to 80°C, more preferably 30 to 60°C. The reaction time is preferably 0.1 to 24 hours, more preferably 1 to 24 hours.

[0082] Specific examples of organic solvents used in the production of the polyamic acid include cyclohexanone, cyclopentanone, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, and 1,3-dimethyl-2-imidazolidinone. Furthermore, when the polyamic acid to be produced has high solvent solubility, solvents such as methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, diethylene glycol monomethyl ether, and diethylene glycol monoethyl ether can be used.

[0083] <Solution Viscosity and Molecular Weight of Polyamic Acid> From the viewpoint of workability, the polyamic acid used in the present invention preferably has a solution viscosity of, for example, 10 to 1,000 mPa·s when prepared as a 10 to 15% by weight solution. The solution viscosity (mPa·s) of the polymer is a value measured at 25°C using an E-type rotational viscometer on a 10 to 15% by weight polymer solution prepared using a good solvent for the polymer (e.g., γ-butyrolactone, N-methyl-2-pyrrolidone, etc.). The polyamic acid preferably has a weight average molecular weight (Mw) in terms of polystyrene measured by gel permeation chromatography (GPC) of 1,000 to 500,000, more preferably 2,000 to 300,000. The molecular weight distribution (Mw / Mn), expressed as the ratio of Mw to the number average molecular weight (Mn) in terms of polystyrene measured by GPC, is preferably 15 or less, more preferably 10 or less. By ensuring that the molecular weight is within this range, good alignment and stability of the liquid crystal display device can be ensured.

[0084] The liquid crystal aligning agent of the present invention may contain a polymer other than the polymer (A), the polymer (B), and the polymer (B'). Specific examples of the other polymer include at least one polymer (Q) selected from the group consisting of polyimide precursors other than the polymer (A), the polymer (B), and the polymer (B') and polyimides that are imidized products of the polyimide precursors, polysiloxane, polyester, polyamide, polyurea, polyorganosiloxane, cellulose derivative, polyacetal, polystyrene derivative, poly(styrene-maleic anhydride) copolymer, poly(isobutylene-maleic anhydride) copolymer, poly(vinyl ether-maleic anhydride) copolymer, poly(styrene-phenylmaleimide) derivative, and a polymer selected from the group consisting of poly(meth)acrylate. Specific examples of poly(styrene-maleic anhydride) copolymers include SMA1000, SMA2000, and SMA3000 (manufactured by Cray Valley Corporation), and GSM301 (manufactured by Gifu Ceramics Manufacturing Co., Ltd.). A specific example of poly(isobutylene-maleic anhydride) copolymers includes ISOBAN-600 (manufactured by Kuraray Co., Ltd.). A specific example of poly(vinyl ether-maleic anhydride) copolymers includes Gantrez AN-139 (methyl vinyl ether maleic anhydride resin, manufactured by Ashland). One type of other polymer may be used alone, or two or more types may be used in combination. The content ratio of the other polymer is preferably 10 to 90 parts by mass, more preferably 20 to 80 parts by mass, per 100 parts by mass of the polymer component contained in the liquid crystal alignment agent. In this specification, the polymer component is a general term for the polymer (A), the polymer (B), the polymer (B'), and other polymers contained in the liquid crystal aligning agent. When the polymers contained in the liquid crystal aligning agent are only the polymer (A) and the polymer (B), the polymer component refers to the polymer (A) and the polymer (B).

[0085] Another embodiment of the present invention includes the following liquid crystal aligning agent. A liquid crystal aligning agent capable of forming a liquid crystal alignment film having a pretilt angle of 0° or more and less than 3° and a change in pretilt angle represented by the following formula 1 of less than 0.3°, the liquid crystal aligning agent comprising the following polymer (A) and polymer (B), or polymer (B) and polymer (B'). (However, polymer (A) excludes polymer (B).) Polymer (A): Polyamic acid (A) having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, wherein the structural unit derived from the tetracarboxylic acid derivative is a polyamic acid (A) having the following formula (1T ａ As a diamine-derived structural unit, a structural unit (a-1Ta) represented by the following formula (1D ａ Polymer (B): The polyamic acid (B) has a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, wherein the structural unit derived from the tetracarboxylic acid derivative is represented by the following formula (1T ｂ As a diamine-derived structural unit, a structural unit (b-1Tb) represented by the following formula (1D ｂ and at least a part of the terminals of the polyamic acid (B) contain a non-amino group, and the non-amino group is a functional group represented by the following structural formula (E). Polymer (B'): The polyamic acid (B') has a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, and the structural unit derived from the tetracarboxylic acid derivative contains a structural unit (b-1Db) represented by the following structural formula (1T ｂ ) and the structural unit (b-1Tb) represented by the above formula (1T ａ As a diamine-derived structural unit, the structural unit (a-1Da) represented by the following formula (1D ｂ ) or a structural unit (b-1Db) represented by the following formula (1D ｂ’ ), and the abundance rate of terminal amino groups in the polyamic acid (B') is greater than 60% based on all terminals of the polyamic acid (B). (X in the formula ａ is a tetravalent organic group represented by the following formula (x-2), or a tetravalent organic group having an alicyclic structure of five or more members (T ５ａ ) is represented by the formula (1D ａ ) in Y ａ represents a divalent organic group derived from a diamine. Each Z independently represents a hydrogen atom or a monovalent organic group. (X in the formula ｂ represents a tetravalent organic group derived from an aromatic tetracarboxylic dianhydride. ｂ ) in Y ｂ is diamine (0) "H-N(Z)-Ar １ -L １ -A-L １’ -Ar １’ -N(Z)-H', or diamine (0')'H-N(Z)-Ar ２ -L ２ -A ２ -L ２’ -Ar ２’ represents a divalent organic group derived from "-N(Z)-H". １ , Ar １’ each independently represents a benzene ring, a biphenyl structure, or a naphthalene ring. １ , Ar １’ Any hydrogen atom on the ring may be substituted with a monovalent group. A represents a divalent organic group having an alkylene structure and having 1 to 10 carbon atoms. L １ , L １’ are each independently a single bond, -O-, -S-, -C(=O)-, -O-C(=O)-, -NR- (R represents a hydrogen atom or a monovalent organic group), -C(=O)-NR- (R represents a hydrogen atom or a monovalent organic group), or -NR-C(=O)- (R represents a hydrogen atom or a monovalent organic group). ２ and Ar ２’ each independently represents a benzene ring, a biphenyl structure, a naphthalene ring, or an aromatic heterocycle. ２ and Ar ２’ Any hydrogen atom on the ring of A may be substituted with a monovalent group. ２ represents a divalent organic group having an alkylene group. ２ , L ２’are each independently a single bond, -O-, -S-, -C(=O)-, -O-C(=O)-, -NR- (R represents a hydrogen atom or a monovalent organic group), -C(=O)-NR- (R represents a hydrogen atom or a monovalent organic group), or -NR-C(=O)- (R represents a hydrogen atom or a monovalent organic group). ２ and Ar ２’ and A ２ Z is a group represented by the above formula (1D ａ ) is synonymous with Z in (In formula (E), Q is a monovalent organic group selected from any of the following groups (e1) to (e3). * represents a bond.) (e1) an acyclic hydrocarbon group having 1 to 6 carbon atoms; (e2) a monovalent organic group having 1 or 2 carboxy groups and 2 to 30 carbon atoms (provided that the monovalent organic group does not contain an acid anhydride group); (e3) a monovalent organic group having two or more Boc groups and having 1 to 30 carbon atoms excluding Boc, the monovalent organic group being selected from the group consisting of *1-NH(Boc), *1-N(Boc), ２ and "*1-N(Boc)-*1" (*1 represents a bond bonded to a carbon atom). When there are two or more protected amino moieties, the respective protected amino moieties may be the same or different. (Formula (1D ｂ’ ) in Y ｂ’ is a diamine (1) "H-N(Z)-Ar ３ represents a divalent organic group derived from the group consisting of Ar, Ar(Z), ... ３ is -Ar ４ -NR １ -Ar ４’ -, -Ar ４１ -Ar ４２ -, or three or more cyclic groups selected from the group consisting of a benzene ring and a heterocycle are directly or ２ The divalent organic group is bonded to two -N(Z)- groups via aromatic carbon atoms contained in a benzene ring or a heterocycle, and the two aromatic carbon atoms are not contained in the same cyclic group. ４ and Ar ４’each represents a benzene ring or an aromatic heterocycle. ４１ and Ar ４２ each represents a benzene ring or an aromatic heterocycle, and Ar ４１ and Ar ４２ One of Ar represents a benzene ring, and the other represents an aromatic heterocycle. ３ Any hydrogen atom on the benzene ring or aromatic heterocycle of Ar １ , Ar １’ may be substituted with a monovalent group exemplified by —NR １ -, -NR ２ R in - １ , R ２ , represent a hydrogen atom or a monovalent organic group. [Formula 1] Δ=|Δb-Δa| Δ: change in pretilt angle after storage at room temperature for 48 hours Δa: pretilt angle of liquid crystal cell Δb: pretilt angle of liquid crystal cell using the same liquid crystal alignment agent left at room temperature for 48 hours (In the formula 1, the pretilt angle represents a value measured in the state where no voltage is applied to a liquid crystal cell obtained by using two substrates with liquid crystal alignment films.)

[0086] In the above formula 1, the pretilt angle can be measured using, for example, "OPTIPRO-micro" manufactured by SHINTECH Corporation.

[0087] The change in pretilt angle represented by the above formula 1 is preferably 0.2° or less, more preferably 0.1° or less. The change in pretilt angle of the liquid crystal cell using the liquid crystal aligning agent according to another embodiment of the present invention is a value of less than 0.3°, and the change in pretilt angle due to leaving at room temperature is suppressed. The meanings of each symbol in the liquid crystal aligning agent according to another embodiment of the present invention, including preferred embodiments, are the same as the symbols of the liquid crystal aligning agent described above.

[0088] <Liquid Crystal Aligning Agent> The liquid crystal aligning agent of the present invention is used to prepare a liquid crystal alignment film and takes the form of a coating liquid from the viewpoint of forming a uniform thin film. The liquid crystal aligning agent of the present invention is also preferably a coating liquid containing the above-described polymer component and a solvent. The content (concentration) of the polymer component contained in the liquid crystal aligning agent of the present invention can be appropriately changed depending on the thickness of the coating film to be formed. However, from the viewpoint of forming a uniform and defect-free coating film, it is preferably 1% by mass or more relative to the total amount of the liquid crystal aligning agent, and from the viewpoint of storage stability of the solution, it is preferably 10% by mass or less. From the viewpoint of suitably obtaining the effects of the present disclosure, the total content ratio of polymer (A) (or polymer (B)') and polymer (B) in the liquid crystal aligning agent 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 100 parts by mass of the total polymers contained in the liquid crystal aligning agent. When the liquid crystal aligning agent contains other polymers, the content ratio of the polymer (A) and the polymer (B) is preferably 10 to 90 parts by mass, more preferably 20 to 80 parts by mass, relative to 100 parts by mass of the polymer components contained in the liquid crystal aligning agent.

[0089] The solvent contained in the liquid crystal aligning agent is not particularly limited as long as it can uniformly dissolve the polymer component. Specific examples thereof include N,N-dimethylformamide, N,N-dimethylacetamide, N,N-dimethyllactamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethyl sulfoxide, γ-butyrolactone, γ-valerolactone, 1,3-dimethyl-2-imidazolidinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, 3-methoxy-N,N-dimethylpropanamide, and 3-butoxy-N,N-dimethylpropanamide. , N-(n-propyl)-2-pyrrolidone, N-isopropyl-2-pyrrolidone, N-(n-butyl)-2-pyrrolidone, N-(tert-butyl)-2-pyrrolidone, N-(n-pentyl)-2-pyrrolidone, N-(3-methoxypropyl)-2-pyrrolidone, N-(2-ethoxyethyl)-2-pyrrolidone, N-(4-methoxybutyl)-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone (collectively referred to as "good solvents"). Among these, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, and γ-butyrolactone are preferred. The content of the good solvent is preferably 20 to 99% by mass, more preferably 20 to 90% by mass, and particularly preferably 30 to 80% by mass of the total solvent contained in the liquid crystal aligning agent.

[0090] In addition, the solvent contained in the liquid crystal aligning agent is preferably a mixed solvent containing, in addition to the above solvent, a solvent (also called a poor solvent) that improves the coatability when applying the liquid crystal aligning agent and the surface smoothness of the coating film. Specific examples of the poor solvent to be used in combination are listed below, but are not limited thereto.

[0091] For example, diisopropyl ether, diisobutyl ether, diisobutyl carbinol (2,6-dimethyl-4-heptanol), ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, 4-hydroxy-4-methyl-2-pentanone, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, 3-ethoxybutyl acetate, 1-methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, ethylene glycol monoacetate, ethylene glycol diacetate, propylene carbonate, ethylene carbonate, ethylene glycol monobutyl ether, ethylene glycol monoisoamyl ether, ethylene glycol monohexyl ether, propylene glycol monobutyl ether, 1-(2-butoxyethoxy)-2-propanol Examples of the lactic acid bacteria include 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, and diisobutyl ketone (2,6-dimethyl-4-heptanone). The content of the poor solvent is preferably 1 to 80 mass %, more preferably 10 to 80 mass %, and particularly preferably 20 to 70 mass % of the total solvent contained in the liquid crystal aligning agent. The type and content of the poor solvent are appropriately selected depending on the coating device, coating conditions, coating environment, etc. of the liquid crystal aligning agent.

[0092] Of these, diisobutyl carbinol, propylene glycol monobutyl ether, propylene glycol diacetate, diethylene glycol diethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, or diisobutyl ketone is preferred.

[0093] Preferred solvent combinations of a good solvent and a poor solvent include N-methyl-2-pyrrolidone and ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone and ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone and propylene glycol monobutyl ether, N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone, 4-hydroxy-4-methyl-2-pentanone and diethylene glycol diethyl ether, and N-methyl-2-pyrrolidone and γ- butyrolactone, propylene glycol monobutyl ether, and diisobutyl ketone; N-methyl-2-pyrrolidone, γ-butyrolactone, propylene glycol monobutyl ether, and diisopropyl ether; N-methyl-2-pyrrolidone, γ-butyrolactone, propylene glycol monobutyl ether, and diisobutyl carbinol; N-methyl-2-pyrrolidone, γ-butyrolactone, and dipropylene glycol dimethyl ether; and N-methyl-2-pyrrolidone, propylene glycol monobutyl ether, and dipropylene glycol dimethyl ether.

[0094] The liquid crystal aligning agent of the present invention may additionally contain components other than the polymer component and the solvent (hereinafter also referred to as additive components). Examples of such additive components include a compound for increasing the strength of the liquid crystal alignment film (hereinafter also referred to as crosslinking compound), an adhesion aid for increasing the adhesion between the liquid crystal alignment film and the substrate or between the liquid crystal alignment film and a sealant, a dielectric or conductive substance for adjusting the dielectric constant or electrical resistance of the liquid crystal alignment film, or an imidization accelerator for promoting imidization.

[0095] Examples of the crosslinkable compound include at least one crosslinkable compound selected from the group consisting of a crosslinkable compound (c-1) having at least one substituent selected from an epoxy group, an oxetanyl group, an oxazoline structure, a cyclocarbonate group, a blocked isocyanate group, a hydroxy group, and an alkoxy group, and a crosslinkable compound (c-2) having a polymerizable unsaturated group. Specific preferred examples of the crosslinkable compounds (c-1) and (c-2) include the following compounds: Examples of compounds having an epoxy group include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol, bisphenol A epoxy resins such as Epikote 828 (manufactured by Mitsubishi Chemical Corporation), bisphenol F epoxy resins such as Epikote 807 (manufactured by Mitsubishi Chemical Corporation), and hydrogenated bisphenols such as YX-8000 (manufactured by Mitsubishi Chemical Corporation). phenol A type epoxy resins, biphenyl skeleton-containing epoxy resins such as YX6954BH30 (manufactured by Mitsubishi Chemical Corporation), phenol novolac type epoxy resins such as EPPN-201 (manufactured by Nippon Kayaku Co., Ltd.), (o, m, p-) cresol novolac type epoxy resins such as EOCN-102S (manufactured by Nippon Kayaku Co., Ltd.), compounds in which a tertiary nitrogen atom is bonded to an aromatic carbon atom such as tetrakis(glycidyloxymethyl)methane, N,N,N',N'-tetraglycidyl-1,4-phenylenediamine, N,N,N',N'-tetraglycidyl-2,2'-dimethyl-4.4'-diaminobiphenyl, 2,2-bis[4-(N,N-diglycidyl-4-aminophenoxy)phenyl]propane, and N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane;N,N,N',N'-tetraglycidyl-1,2-diaminocyclohexane, N,N,N',N'-tetraglycidyl-1,3-diaminocyclohexane, N,N,N',N'-tetraglycidyl-1,4-diaminocyclohexane, bis(N,N-diglycidyl-4-aminocyclohexyl)methane, bis(N,N-diglycidyl-2-methyl-4-aminocyclohexyl)methane, bis(N,N-diglycidyl-3-methyl-4-aminocyclohexyl)methane, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, 1,4-bis(N,N-diglycidylaminomethyl) ) cyclohexane, 1,3-bis(N,N-diglycidylaminomethyl)benzene, 1,4-bis(N,N-diglycidylaminomethyl)benzene, 1,3,5-tris(N,N-diglycidylaminomethyl)cyclohexane, 1,3,5-tris(N,N-diglycidylaminomethyl)benzene and other compounds in which a tertiary nitrogen atom is bonded to an aliphatic carbon atom; isocyanurate compounds such as triglycidyl isocyanurate such as TEPIC (manufactured by Nissan Chemical Industries, Ltd.); compounds described in paragraph

[0037] of JP-A-10-338880 and compounds described in WO2017 / 170483; Examples of compounds having an oxetanyl group include 1,4-bis{[(3-ethyl-3-oxetanyl)methoxy]methyl}benzene (Aron Oxetane OXT-121 (XDO)), bis[2-(3-oxetanyl)butyl]ether (Aron Oxetane OXT-221 (DOX)), 1,4-bis[(3-ethyloxetan-3-yl)methoxy]benzene (HQOX), 1,3-bis[(3-ethyloxetan-3-yl)methoxy]benzene (RSOX), 1,2-bis[(3-ethyloxetan-3-yl)methoxy]benzene (CTOX), and compounds having two or more oxetanyl groups described in paragraphs

[0170] to

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

[0115] of Japanese Patent Application Laid-Open No. 2007-286597;Examples of compounds having a cyclocarbonate group include N,N,N',N'-tetra[(2-oxo-1,3-dioxolan-4-yl)methyl]-4,4'-diaminodiphenylmethane, N,N',-di[(2-oxo-1,3-dioxolan-4-yl)methyl]-1,3-phenylenediamine, and the compounds described in paragraphs

[0025] to

[0030] and

[0032] of WO2011 / 155577; Examples of compounds having a blocked isocyanate group include Coronate AP Stable M, Coronate 2503, 2515, 2507, 2513, 2555, and Millionate MS-50 (all manufactured by Tosoh Corporation), Takenate B-830, B-815N, B-820NSU, B-842N, B-846N, B-870N, B-874N, and B-882N (all manufactured by Mitsui Chemicals, Inc.), compounds having two or more blocked isocyanate groups described in paragraphs

[0046] to

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

[0119] to

[0120] of WO2015 / 141598; Examples of compounds having a hydroxy group and / or an alkoxy group include N,N,N',N'-tetrakis(2-hydroxyethyl)adipamide, 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethoxyphenyl)propane, 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl)-1,1,1,3,3,3-hexafluoropropane, compounds described in WO2015 / 072554 and paragraph

[0058] of JP2016-118753A, compounds described in JP2016-200798A, and compounds described in WO2010 / 074269A;Examples of crosslinkable compounds having a polymerizable unsaturated group include glycerin mono(meth)acrylate, glycerin di(meth)acrylate (1,2-, 1,3-mixture), glycerin tris(meth)acrylate, glycerol 1,3-diglycerolate di(meth)acrylate, pentaerythritol tri(meth)acrylate, diethylene glycol mono(meth)acrylate, triethylene glycol mono(meth)acrylate, tetraethylene glycol mono(meth)acrylate, pentaethylene glycol mono(meth)acrylate, and hexaethylene glycol mono(meth)acrylate;

[0096] The above compounds are examples of crosslinkable compounds, and are not limited thereto. For example, components other than those described above are disclosed on pages 53

[0105] to 55

[0116] of WO2015 / 060357. Two or more types of crosslinkable compounds may be combined.

[0097] When a crosslinkable compound is used, the content of the crosslinkable compound in the liquid crystal aligning agent is preferably 0.5 to 20 parts by mass, more preferably 1 to 15 parts by mass, relative to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent.

[0098] Examples of the adhesion aid include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyl trimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-3-triethoxysilylpropyltriethylenetetramine, N-3-trimethoxysilylpropyltriethylenetetramine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N- Benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxy Examples of silane coupling agents include silane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, tris[3-(trimethoxysilyl)propyl]isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-isocyanatopropyltriethoxysilane.When an adhesion aid is used, the content of the adhesion aid in the liquid crystal aligning agent is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, relative to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent. Examples of dielectric or conductive substances include monoamines having a nitrogen-containing aromatic heterocycle, such as 3-picolylamine. When a dielectric or conductive substance is used, the content of the dielectric or conductive substance in the liquid crystal aligning agent is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, relative to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent.

[0099] (Liquid crystal alignment film) The liquid crystal alignment film of the present invention is formed using the liquid crystal aligning agent of the present invention. The method for producing a liquid crystal alignment film of the present invention includes, for example, applying the liquid crystal aligning agent to a substrate, baking the applied liquid crystal aligning agent, and irradiating the resulting film with polarized radiation. A preferred embodiment of the method for producing a liquid crystal alignment film of the present invention includes, for example, a method for producing a liquid crystal alignment film including a step of applying the liquid crystal aligning agent to a substrate (step (1)), a step of baking the applied liquid crystal aligning agent (step (2)), and, optionally, a step of performing an alignment treatment on the film obtained in step (2) (step (3)).

[0100] <Step (1)> The substrate onto which the liquid crystal aligning agent used in the present invention is applied is not particularly limited as long as it is a highly transparent substrate, and glass substrates, silicon nitride substrates, acrylic substrates, polycarbonate substrates, and other plastic substrates can also be used. In this case, using a substrate on which an ITO (Indium Tin Oxide) electrode for driving the liquid crystal is formed is preferable from the viewpoint of simplifying the process. Furthermore, in a reflective liquid crystal display element, an opaque material such as a silicon wafer can be used for only one substrate, and in this case, a light-reflecting material such as aluminum can also be used for the electrode. Furthermore, when manufacturing an IPS drive system or FFS drive system liquid crystal display element, a substrate provided with an electrode made of a comb-shaped patterned transparent conductive film or metal film and an opposing substrate without an electrode are used.

[0101] Examples of a method for applying the liquid crystal alignment agent to a substrate and forming a film include screen printing, offset printing, flexographic printing, an inkjet method, and a spray method. Among these, the application and film formation method by the inkjet method is preferably used.

[0102] An IPS substrate, which is a comb-teeth electrode substrate used in an IPS system (mode), has a base material, a plurality of linear electrodes formed on the base material and arranged in a comb-teeth pattern, and a liquid crystal alignment film formed on the base material so as to cover the linear electrodes. Meanwhile, an FFS substrate, which is a comb-teeth electrode substrate used in an FFS system (mode), has a base material, a surface electrode formed on the base material, an insulating film formed on the surface electrode, a plurality of linear electrodes formed on the insulating film and arranged in a comb-teeth pattern, and a liquid crystal alignment film formed on the insulating film so as to cover the linear electrodes.

[0103] FIG. 1 is a schematic cross-sectional view showing an example of an IPS-mode in-plane switching liquid crystal display element having a liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention. In the in-plane switching liquid crystal display element 1 shown in FIG. 1 , liquid crystal 3 is sandwiched between a comb-shaped electrode substrate 2 having a liquid crystal alignment film 2c and a counter substrate 4 having a liquid crystal alignment film 4a. The comb-shaped electrode substrate 2 has a base 2a, a plurality of linear electrodes 2b formed on the base 2a and arranged in a comb-like pattern, and a liquid crystal alignment film 2c formed on the base 2a to cover the linear electrodes 2b. The counter substrate 4 has a base 4b and a liquid crystal alignment film 4a formed on the base 4b. The liquid crystal alignment film 2c is a liquid crystal alignment film of the present invention. The liquid crystal alignment film 4c is also a liquid crystal alignment film of the present invention. In the in-plane switching liquid crystal display element 1 of FIG. 1 , when a voltage is applied to the linear electrodes 2b, an electric field is generated between the linear electrodes 2b, as indicated by electric field lines L.

[0104] Figure 2 is a schematic cross-sectional view showing an example of an FFS-mode in-plane switching liquid crystal display element having a liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention. In the in-plane switching liquid crystal display element 1 shown in Figure 2, liquid crystal 3 is sandwiched between a comb-shaped electrode substrate 2 having a liquid crystal alignment film 2h and a counter substrate 4 having a liquid crystal alignment film 4a. The comb-shaped electrode substrate 2 has a base 2d, a surface electrode 2e formed on the base 2d, an insulating film 2f formed on the surface electrode 2e, a plurality of linear electrodes 2g formed on the insulating film 2f and arranged in a comb-like pattern, and a liquid crystal alignment film 2h formed on the insulating film 2f so as to cover the linear electrodes 2g. The counter substrate 4 has a base 4b and a liquid crystal alignment film 4a formed on the base 4b. The liquid crystal alignment film 2h is a liquid crystal alignment film of the present invention. The liquid crystal alignment film 4a is also a liquid crystal alignment film of the present invention. In the IPS LCD element 1 shown in FIG. 2, when a voltage is applied to the surface electrodes 2e and the linear electrodes 2g, an electric field is generated between the surface electrodes 2e and the linear electrodes 2g as indicated by electric force lines L.

[0105] <Step (2)> Step (2) is a step of baking the liquid crystal aligning agent applied to the substrate to form a film. After applying the liquid crystal aligning agent to the substrate, the solvent can be evaporated or the amic acid or amic acid ester in the polymer can be thermally imidized using a heating means such as a hot plate, a heat circulation oven, or an IR (infrared) oven. The drying and baking steps after applying the liquid crystal aligning agent of the present invention can be performed at any temperature and for any time, and may be performed multiple times. The temperature for evaporating the solvent in the liquid crystal aligning agent can be, for example, 40 to 180°C as the heating means temperature, but may also be 40 to 150°C from the perspective of shortening the process. The baking time is not particularly limited, but is, for example, 1 to 10 minutes, preferably 1 to 5 minutes. When a step of thermally imidizing the amic acid in the polymer is performed in addition to the step of evaporating the solvent, a further baking step can be performed after the solvent evaporation step at a heating means temperature of, for example, 150 to 300°C, preferably 150 to 250°C. The baking time in the thermal imidization step is not particularly limited, but is, for example, 5 to 40 minutes, preferably 5 to 30 minutes. If the film-like substance after baking is too thin, the reliability of the liquid crystal display element may decrease, so the thickness is preferably 5 to 300 nm, more preferably 10 to 200 nm.

[0106] <Step (3)> Step (3) is a step of subjecting the film obtained in step (2) to an alignment treatment. Examples of alignment treatment methods for liquid crystal alignment films include rubbing treatment and photo-alignment treatment, with photo-alignment treatment being preferred. Examples of photo-alignment treatment methods include irradiating the surface of the film with polarized radiation in a certain direction, and optionally performing a heat treatment to impart liquid crystal alignment properties (also referred to as liquid crystal alignment ability). As the radiation, ultraviolet light or visible light having a wavelength of 100 to 800 nm can be used. Of these, ultraviolet light having a wavelength of 100 to 400 nm is preferred, and more preferably 200 to 400 nm.

[0107] The radiation dose is 1 to 10,000 mJ / cm ２ is preferred, and 100 to 5,000 mJ / cm ２is more preferable. Examples of light sources that can be used for the irradiation light include low-pressure mercury lamps, high-pressure mercury lamps, deep UV lamps, deuterium lamps, metal halide lamps, argon resonance lamps, xenon lamps, mercury-xenon lamps, excimer lasers (e.g., KrF excimer lasers), fluorescent lamps, LED lamps, halogen lamps (e.g., sodium lamps), and microwave-excited electrodeless lamps. Furthermore, when polarized light is used as the irradiation light, the higher the extinction ratio of polarized light, the higher the anisotropy that can be imparted. For example, in the case of ultraviolet light, the extinction ratio of polarized ultraviolet light is more preferably 10:1 or greater, and even more preferably 20:1 or greater. Furthermore, when irradiating with radiation, in order to improve the liquid crystal alignment, the substrate having the film-like material may be irradiated while being heated at 50 to 250°C. 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 by the above method can be contacted with a solvent or the radiation-irradiated liquid crystal alignment film can be heat-treated.

[0108] The solvent used in the contact treatment is not particularly limited, as long as it dissolves the decomposition products generated from the film-like material by irradiation with radiation. Specific examples include water, methanol, ethanol, 2-propanol, acetone, methyl ethyl ketone, 1-methoxy-2-propanol, 1-methoxy-2-propanol acetate, butyl cellosolve, ethyl lactate, methyl lactate, diacetone alcohol, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propyl acetate, butyl acetate, and cyclohexyl acetate. Among these, water, 2-propanol, 1-methoxy-2-propanol, and ethyl lactate are preferred from the viewpoints of versatility and solvent safety. Water, 1-methoxy-2-propanol, and ethyl lactate are more preferred. The solvent may be one type or a combination of two or more types.

[0109] Examples of the contact treatment include immersion treatment and spray treatment (also referred to as spray treatment). The treatment time in these treatments is preferably 10 seconds to 1 hour from the viewpoint of efficiently dissolving the decomposition products generated from the film-like material by irradiation with radiation. In particular, immersion treatment for 1 minute to 30 minutes is more preferable. The solvent used in the contact treatment may be at room temperature or heated, preferably 10 to 80°C, and more preferably 20 to 50°C. In addition, ultrasonic treatment or the like may be performed as necessary from the viewpoint of the solubility of the decomposition products.

[0110] After the contact treatment, it is preferable to perform rinsing (also referred to as "rinsing") with a low-boiling solvent such as water, methanol, ethanol, 2-propanol, acetone, or methyl ethyl ketone, or to perform baking. In this case, either rinsing or baking may be performed, or both may be performed. The baking temperature is preferably 150 to 300°C, more preferably 180 to 250°C, and even more preferably 200 to 230°C. The baking time is preferably 10 seconds to 30 minutes, more preferably 1 minute to 10 minutes. The heat treatment of the coating film irradiated with radiation is preferably performed at 50 to 300°C for 1 minute to 30 minutes, and more preferably at 120 to 250°C for 1 minute to 30 minutes.

[0111] (Liquid Crystal Display Element) The liquid crystal display element of the present invention has the liquid crystal alignment film of the present invention. From the viewpoint of obtaining high liquid crystal alignment properties, the liquid crystal alignment film of the present invention is suitable as a liquid crystal alignment film for in-plane switching mode liquid crystal display elements such as IPS mode and FFS mode, and is particularly useful as a liquid crystal alignment film for FFS mode liquid crystal display elements. The liquid crystal display element can be manufactured by obtaining a substrate with a liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention, preparing a liquid crystal cell by a known method, and arranging liquid crystal in the liquid crystal cell. Specifically, the following two methods can be mentioned.

[0112] In the first method, two substrates are placed opposite each other with a gap (cell gap) between them so that their liquid crystal alignment films face each other, and then the peripheries of the two substrates are bonded together using a sealant. A liquid crystal composition is injected into the substrate surfaces and the cell gap defined by the sealant so that it comes into contact with the film surface, and the injection hole is then sealed.

[0113] The second method is called the ODF (One Drop Fill) method. For example, a UV-curable sealant is applied to a predetermined location on one of two substrates on which a liquid crystal alignment film has been formed, and a liquid crystal composition is then dropped onto several predetermined locations on the liquid crystal alignment film surface. The other substrate is then attached so that the liquid crystal alignment film faces the other substrate, and the liquid crystal composition is spread over the entire surface of the substrate and brought into contact with the film surface. Next, the entire surface of the substrate is irradiated with UV light to cure the sealant.

[0114] In either the first or second method, it is desirable to further heat the coating film to a temperature at which the liquid crystal composition is in an isotropic phase, and then slowly cool it to room temperature to remove flow alignment that occurs during liquid crystal filling. When rubbing treatment is performed on the coating film, the two substrates are positioned opposite each other so that the rubbing directions of the coating films are at a predetermined angle, for example, perpendicular or antiparallel. Similarly, when photoalignment treatment is performed, the substrates are positioned opposite each other so that the alignment directions are at a predetermined angle, for example, perpendicular or antiparallel. Examples of sealing agents that can be used include epoxy resins containing a curing agent and aluminum oxide spheres as spacers. Examples of liquid crystals include nematic liquid crystals and smectic liquid crystals, with nematic liquid crystals being preferred.

[0115] The liquid crystal composition is not particularly limited and is a composition containing at least one liquid crystal compound (liquid crystal molecule). It may be a liquid crystal composition having a positive dielectric anisotropy (also called a positive liquid crystal composition or positive liquid crystal) or a liquid crystal composition having a negative dielectric anisotropy (also called a negative liquid crystal composition or negative liquid crystal). However, a negative liquid crystal material is preferred. The liquid crystal composition may contain a liquid crystal compound having a fluorine atom, a hydroxy group, an amino group, a fluorine atom-containing group (e.g., a trifluoromethyl group), a cyano group, an alkyl group, an alkoxy group, an alkenyl group, an isothiocyanate group, a heterocycle, a cycloalkane, a cycloalkene, a steroid skeleton, a benzene ring, or a naphthalene ring. It may also contain a compound having two or more rigid moieties (mesogenic skeletons) exhibiting liquid crystallinity within the molecule (e.g., a bimesogenic compound in which two rigid biphenyl or terphenyl structures are connected by an alkyl group). The liquid crystal composition may be a liquid crystal composition exhibiting a nematic phase, a liquid crystal composition exhibiting a smectic phase, or a liquid crystal composition exhibiting a cholesteric phase. Furthermore, additives may be further added to the liquid crystal composition in order to improve the liquid crystal alignment properties. Examples of such additives include photopolymerizable monomers such as compounds having a polymerizable group, optically active compounds (e.g., S-811 manufactured by Merck & Co., Inc.), antioxidants, ultraviolet absorbers, dyes, antifoaming agents, polymerization initiators, or polymerization inhibitors. Examples of positive liquid crystals include ZLI-2293, ZLI-4792, MLC-2003, MLC-2041, MLC-3019, and MLC-7081 manufactured by Merck & Co., Inc. Examples of negative liquid crystals include MLC-6608, MLC-6609, MLC-6610, MLC-6882, MLC-6886, MLC-7026, MLC-7026-000, MLC-7026-100, and MLC-7029 manufactured by Merck. Furthermore, in the PSA mode, an example of a liquid crystal containing a compound having a polymerizable group is MLC-3023 manufactured by Merck. Next, polarizing plates are placed. Specifically, a pair of polarizing plates are attached to the surfaces of the two substrates opposite the liquid crystal layer.Examples of the polarizing plate include a polarizing film called an "H film" made by stretching and aligning polyvinyl alcohol and absorbing iodine, sandwiched between cellulose acetate protective films, and a polarizing plate made of the H film itself.

[0116] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. The abbreviations of the compounds used and the methods for measuring the physical properties are as follows:

[0117] (Organic solvent) NMP: N-methyl-2-pyrrolidone BCS: Butyl cellosolve (ethylene glycol monobutyl ether) GBL: γ-butyrolactone

[0118] (Tetracarboxylic acid dianhydride)

[0119] (diamine)

[0120] (Amino terminal modifying agent) Ac ２ O: Acetic anhydride SA: Succinic anhydride

[0121] (Additives) AD-1: 3-glycidoxypropyltriethoxysilane AD-2: Compound of the following structural formula

[0122] <Measurement of Viscosity> Measurement was performed using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.) with a sample volume of 1.1 mL and a cone rotor TE-1 (1°34', R24) at a temperature of 25°C. <Evaluation of the Prevalence of Terminal Amino Groups> 2.0 g of the polyamic acid solution was added to 10 g of isopropyl alcohol, and the resulting precipitate was separated by filtration. This precipitate was washed with isopropyl alcohol and dried under reduced pressure at 60°C to obtain a polyamic acid powder, and then １ The structure was analyzed by H-NMR analysis. The peak intensity of the terminal amino group of the polyamic acid powder without terminal modification was used as a reference, and the abundance ratio of the terminal amino group was calculated from the ratio of the peak intensity of the terminal amino group of each polyamic acid powder (measurement conditions are as follows). Apparatus: BRUKER ADVANCE III-500 MHz Measurement solvent: deuterated dimethyl sulfoxide (DMSO-d ６) or deuterated chloroform (CDCl ３ ) Reference substance: tetramethylsilane (TMS) (δ 0.0 ppm for １ H)

[0123] [Polymer Synthesis] <Synthesis Example 1> 1.43 g (5.0 mmol) of DA-1, 0.73 g (3.0 mmol) of DA-2, and 0.79 g (2.0 mmol) of DA-3 were weighed into a 50 mL recovery flask equipped with a stirrer and a nitrogen inlet tube, and 21.7 g of NMP was added. The mixture was stirred and dissolved while supplying nitrogen. While stirring this diamine solution under water cooling, 2.11 g (9.7 mmol) of CA-1 was added, and then 15.5 g of NMP was added. The mixture was stirred at 50°C for 20 hours under a nitrogen atmosphere to obtain a polyamic acid solution (A-1). <Synthesis Example 2> 3.67 g (18.4 mmol) of DA-4 and 0.91 g (4.6 mmol) of DA-5 were weighed into a 100 mL recovery flask equipped with a stirrer and a nitrogen inlet tube, and 25.9 g of NMP was added. The mixture was stirred and dissolved while supplying nitrogen. While stirring this diamine solution under water cooling, 0.95 g (4.8 mmol) of CA-2 was added, and then 5.4 g of NMP was added, followed by stirring for 30 minutes at 23° C. in a nitrogen atmosphere. Thereafter, while stirring this solution under water cooling, 4.32 g (17.3 mmol) of CA-3 was added, and then 24.5 g of NMP was added, followed by stirring for 12 hours at 50° C. in a nitrogen atmosphere to obtain a polyamic acid solution (B-1).

[0124] Synthesis Example 3: 30 g of the polyamic acid solution (A-1) was mixed with Ac ２ 0.05 g (0.5 mmol) of O was added, and the mixture was stirred at room temperature for 24 hours to obtain a polyamic acid solution (C-1) containing a non-amino group terminal structure.

[0125] [Polymer Synthesis] <Synthesis Example 4> 2.29 g (8.0 mmol) of DA-1 and 0.42 g (2.0 mmol) of DA-6 were weighed into a 100 mL recovery flask equipped with a stirrer and a nitrogen inlet tube, and 24.4 g of NMP was added. The mixture was stirred and dissolved while supplying nitrogen. While stirring this diamine solution under water cooling, 2.03 g (9.3 mmol) of CA-1 was added, and then 18.3 g of NMP was added. The mixture was stirred at 50°C for 20 hours under a nitrogen atmosphere to obtain a polyamic acid solution (A-2). <Synthesis Example 5> 2.29 g (8.0 mmol) of DA-1 and 0.68 g (2.0 mmol) of DA-7 were weighed into a 100 mL recovery flask equipped with a stirrer and a nitrogen inlet tube, and 26.8 g of NMP was added. The mixture was stirred and dissolved while supplying nitrogen. While stirring this diamine solution under water cooling, 2.09 g (9.6 mmol) of CA-1 was added, and then 18.8 g of NMP was added. The mixture was stirred under a nitrogen atmosphere at 50°C for 20 hours to obtain a polyamic acid solution (A-3). <Synthesis Example 6> 2.29 g (8.0 mmol) of DA-1 and 0.78 g (2.0 mmol) of DA-8 were weighed into a 100 mL recovery flask equipped with a stirrer and a nitrogen inlet tube, and 27.6 g of NMP was added. The mixture was stirred while supplying nitrogen and dissolved. While stirring this diamine solution under water cooling, 2.09 g (9.6 mmol) of CA-1 was added, and then 18.8 g of NMP was added. The mixture was stirred under a nitrogen atmosphere at 50°C for 20 hours to obtain a polyamic acid solution (A-4). Synthesis Example 7: 2.86 g (10.0 mmol) of DA-1 was weighed out into a 100 mL recovery flask equipped with a stirrer and a nitrogen inlet tube, and 25.8 g of NMP was added. The mixture was dissolved by stirring while supplying nitrogen. While stirring this diamine solution under water cooling, 2.09 g (9.6 mmol) of CA-1 was added, and then 18.8 g of NMP was added. The mixture was stirred at 50°C under a nitrogen atmosphere for 20 hours to obtain a polyamic acid solution (A-5). Synthesis Example 8: 2.98 g (10.0 mmol) of DA-11 was weighed out into a 100 mL recovery flask equipped with a stirrer and a nitrogen inlet tube, and 26.9 g of NMP was added. The mixture was dissolved by stirring while supplying nitrogen.While stirring this diamine solution under water cooling, 2.09 g (9.6 mmol) of CA-1 was added, and then 18.8 g of NMP was added, and the mixture was stirred under a nitrogen atmosphere at 50°C for 20 hours to obtain a polyamic acid solution (A-6). <Synthesis Example 9> 2.29 g (8.0 mmol) of DA-1 and 0.42 g (2.0 mmol) of DA-13 were weighed into a 100 mL recovery flask equipped with a stirrer and a nitrogen inlet tube, and 24.4 g of NMP was added, and the mixture was stirred and dissolved while supplying nitrogen. While stirring this diamine solution under water cooling, 2.09 g (9.6 mmol) of CA-1 was added, and then 18.8 g of NMP was added, and the mixture was stirred under a nitrogen atmosphere at 50°C for 20 hours to obtain a polyamic acid solution (A-7). Synthesis Example 10 3.99 g (20.0 mmol) of DA-4 and 0.99 g (5.0 mmol) of DA-5 were weighed into a 100 mL recovery flask equipped with a stirrer and a nitrogen inlet tube, and 36.5 g of NMP was added. The mixture was stirred and dissolved while supplying nitrogen. While stirring this diamine solution under water cooling, 3.12 g (12.5 mmol) of CA-3 was added, and then 22.9 g of NMP was added, and the mixture was stirred at 50°C under a nitrogen atmosphere for 3 hours. Thereafter, while stirring this solution under water cooling, 3.31 g (11.3 mmol) of CA-4 was added, and then 24.3 g of NMP was added, and the mixture was stirred at 70°C under a nitrogen atmosphere for 5 hours to obtain polymer solution B-2. Synthesis Example 11 Into a 100 mL recovery flask equipped with a stirrer and a nitrogen inlet tube, 1.87 g (7.5 mmol) of DA-9, 2.49 g (12.5 mmol) of DA-4, and 0.99 g (5.0 mmol) of DA-5 were weighed out, and 39.2 g of NMP was added, followed by stirring while feeding nitrogen to dissolve. While stirring this diamine solution under water cooling, 1.72 g (8.8 mmol) of CA-2 was added, and then 42.0 g of NMP was added, and the mixture was stirred at 25 ° C. under a nitrogen atmosphere for 1 hour. Thereafter, while stirring this solution under water cooling, 4.41 g (15.0 mmol) of CA-4 was added, and then 2.9 g of NMP was added, and the mixture was stirred under a nitrogen atmosphere at 25 ° C. for 5 hours to obtain polymer solution B-3. Synthesis Example 12 4.48 g (15.0 mmol) of DA-11 and 2.44 g (10.0 mmol) of DA-2 were weighed into a 100 mL recovery flask equipped with a stirrer and a nitrogen inlet tube, and 50.7 g of NMP was added, followed by stirring while supplying nitrogen to dissolve the mixture.While stirring this diamine solution under water cooling, 6.99 g (24.0 mmol) of CA-4 was added, and then 51.2 g of NMP was added. The mixture was stirred under a nitrogen atmosphere at 70°C for 10 hours to obtain polymer solution B-4. <Synthesis Example 13> 2.99 g (15.0 mmol) of DA-4, 2.11 g (5.0 mmol) of DA-10, and 1.49 g (5.0 mmol) of DA-11 were weighed into a 100 mL recovery flask equipped with a stirrer and a nitrogen inlet tube, and 48.3 g of NMP was added, followed by stirring and dissolution while supplying nitrogen. While stirring this diamine solution under water cooling, 6.99 g (24.0 mmol) of CA-4 was added, and then 51.2 g of NMP was added. The mixture was stirred under a nitrogen atmosphere at 70°C for 10 hours to obtain polymer solution B-5. Synthesis Example 14 4.48 g (15.0 mmol) of DA-11 and 1.50 g (10.0 mmol) of DA-12 were weighed into a 100 mL recovery flask equipped with a stirrer and a nitrogen inlet tube, 43.8 g of NMP was added, and the mixture was dissolved by stirring while supplying nitrogen. While stirring this diamine solution under water cooling, 4.41 g (22.5 mmol) of CA-2 was added, and then 32.4 g of NMP was added, and the mixture was stirred under a nitrogen atmosphere at 40° C. for 10 hours to obtain Polymer Solution B-6.

[0126] Synthesis Examples 15 to 20 Polymer solutions C-2 to C-7 were obtained in the same manner as in Synthesis Example 3 above, using the polymer solutions and amino terminal modifiers shown in Table 1 below.

[0127] Of the polymer solutions prepared above, the polymers contained in (B-1) to (B-3) and (B-6) are included in polymer (A). The polymers contained in (C-1) to (C-7) are included in polymer (B). The polymers contained in (B-4) and (B-5) are included in polymer (B'). The polymers contained in (A-1) to (A-7) are included in other polymers.

[0128] [Preparation of Liquid Crystal Alignment Agent] Example 1 Using the polyamic acid solution (C-1) and the polyamic acid solution (B-1), 2.9 g of the polyamic acid solution (C-1) and 5.3 g of the polyamic acid solution (B-1) were mixed so that the mass ratio of the two types of polymers was 30:70. To this mixture, NMP (5.6 g), BCS (5.0 g), an NMP solution (1.1 g) containing 1 mass % of AD-1, and an NMP solution (0.3 g) containing 10 mass % of AD-2 were added with stirring, and the mixture was further stirred at room temperature for 2 hours to obtain the liquid crystal alignment agent (AL-1) of Example 1. In addition, in order to evaluate the effect of suppressing pretilt angle change due to storage at room temperature, a liquid crystal alignment agent (AL-1-48h) was also obtained by leaving it at room temperature for 48 hours.

[0129] Comparative Example 1 Using the polyamic acid solution (A-1) and the polyamic acid solution (B-1), 2.9 g of the polyamic acid solution (A-1) and 5.3 g of the polyamic acid solution (B-1) were mixed so that the mass ratio of the two types of polymers was 30:70. To this mixture, NMP (5.6 g), BCS (5.0 g), an NMP solution (1.1 g) containing 1 mass % of AD-1, and an NMP solution (0.3 g) containing 10 mass % of AD-2 were added with stirring, and the mixture was further stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent (AL-R1) of Comparative Example 1. In addition, in order to evaluate the effect of suppressing the pretilt angle change due to storage at room temperature, a liquid crystal aligning agent (AL-R1-48h) was also obtained by leaving it at room temperature for 48 hours.

[0130] <Examples 2 to 9, and Comparative Examples 2 to 6> With the composition shown in Table 2 below, carry out the same operation as in Example 1 above, obtain the liquid crystal aligning agents (AL-2) to (AL-9), (AL-2-48h) to (AL-9-48h) of Examples 2 to 6 of the present invention and the liquid crystal aligning agents (AL-R2) to (AL-R6), (AL-R2-48h) to (AL-R6-48h) of Comparative Examples 2 to 6.

[0131]

[0132] [Preparation of Liquid Crystal Cell] The liquid crystal alignment agent obtained above was used to prepare the following FFS-mode liquid crystal cell. (Configuration of FFS-mode liquid crystal cell) The FFS-mode liquid crystal cell was a set consisting of a first glass substrate on the surface of which was formed a finger-on-plate (FOP) electrode layer consisting of a planar common electrode, an insulating layer, and a comb-shaped pixel electrode, and a second glass substrate on the surface of which was formed a 4 μm-high columnar spacer and on the backside an ITO film for antistatic purposes. The pixel electrode had a comb-like shape in which multiple 3 μm-wide electrode elements, bent at a 160° interior angle in the center, were arranged in parallel at 6 μm intervals, and each pixel had a first region and a second region separated by a line connecting the bends of the multiple electrode elements. The liquid crystal alignment film formed on the first glass substrate was oriented so that the direction equally dividing the interior angle of the pixel bend was perpendicular to the alignment direction of the liquid crystal, and the liquid crystal alignment film formed on the second glass substrate was oriented so that the alignment direction of the liquid crystal on the first substrate would coincide with the alignment direction of the liquid crystal on the second substrate when the liquid crystal cell was fabricated.

[0133] (Preparation of FFS-Driven Liquid Crystal Cell (Rubbing Treatment)) Next, the liquid crystal alignment agents (AL-1) and (AL-1-48h) obtained in Example 1 and the liquid crystal alignment agents (AL-R1) and (AL-R1-48h) obtained in Comparative Example 1 were each filtered through a filter with a pore size of 1.0 μm, and then applied by spin coating to the surface of the electrode-attached substrate and a glass substrate having a 4 μm-high columnar spacer and an ITO film formed on the back surface. After drying for 2 minutes on a hot plate at 80 ° C, the substrate was baked for 30 minutes in a hot air circulating oven at 230 ° C to form a coating film with a thickness of 100 nm. Next, the substrate on which the coating film was formed was rubbed with a rayon cloth (roller diameter: 140 mm, roller rotation speed: 1000 rpm, movement speed: 20 mm / sec, indentation length: 0.4 mm). The substrate was then washed in pure water by ultrasonic irradiation for 1 minute, water droplets were removed by air blowing, and then dried at 80°C for 10 minutes to obtain a substrate with a liquid crystal alignment film. The two obtained substrates were combined into a pair, and a sealant was applied to one substrate. The other substrate was then attached so that the liquid crystal alignment film surfaces faced each other and the alignment direction was 0°. The sealant was then cured to produce an empty cell. Liquid crystal MLC-3019 (manufactured by Merck) was injected into this empty cell by a reduced pressure injection method, and the injection port was sealed to obtain an FFS drive liquid crystal cell. The obtained FFS drive liquid crystal cell was heated at 120°C for 1 hour and left overnight at 23°C before being used for the evaluation described below.

[0134] [Measurement of Pretilt Angle of Liquid Crystal Cell] The pretilt angle of the liquid crystal cell prepared above was measured using an "OPTIPRO-micro" manufactured by SHINTECH Co., Ltd. The pretilt angle represents a value measured in a state where no voltage was applied to a liquid crystal cell obtained using two substrates with liquid crystal alignment films.

[0135] [Evaluation Results] To confirm the effect of suppressing pretilt angle change due to room temperature storage, which is an object of the present invention, the following evaluations were performed. Specifically, the pretilt angle Δa of liquid crystal cells using the liquid crystal alignment agents (AL-1) and (AL-R1) obtained in Example 1 and Comparative Example 1 above was calculated, and the pretilt angle Δb of liquid crystal cells using the liquid crystal alignment agents (AL-1-48h) and (AL-R1-48h) left at room temperature for 48 hours was calculated. Next, the change in pretilt angle Δ(|Δb-Δa|) due to room temperature storage for each liquid crystal alignment agent was calculated. A value less than 0.3° was defined as "Good," and a value equal to or greater than 0.3° was defined as "Poor." The evaluation results are shown in Table 3. In the table, the parenthesized values ​​for the tetracarboxylic acid components represent the amount (in parts by mole) of each tetracarboxylic acid dianhydride used relative to 100 parts by mole of the total amount of tetracarboxylic acid components used in the polymerization.

[0136]

[0137] The pretilt angle change Δ(|Δb-Δa|) was also calculated using the same procedure for the liquid crystal aligning agents (AL-2) to (AL-9), (AL-2-48h) to (AL-9-48h), (AL-R2) to (AL-R6), and (AL-R2-48h) to (AL-R6-48h) obtained in Examples 2 to 9 and Comparative Examples 2 to 6. A value of less than 0.3° was defined as "Good," and a value of 0.3° or greater was defined as "Poor." The evaluation results are shown in Table 4. In the table, the parenthesized values ​​for the tetracarboxylic acid component represent the amount (in parts by mole) of each tetracarboxylic acid dianhydride used relative to 100 parts by mole of the total amount of tetracarboxylic acid components used in the polymerization.

[0138]

[0139] It was confirmed that the liquid crystal cell using the liquid crystal aligning agent of the present invention had a pretilt variation of less than 0.3°, and the variation in the pretilt angle due to standing at room temperature was suppressed.

[0140] The entire contents of the specification, claims, drawings and abstract of Japanese Patent Application No. 2023-067330 filed on April 17, 2023 are hereby incorporated by reference as the disclosure of the specification of the present invention.

Claims

1. A liquid crystal aligning agent capable of forming a liquid crystal alignment film having a pretilt angle of 0° or more and less than 3°, characterized in that the liquid crystal aligning agent contains the following polymer (A) and polymer (B), or polymer (B) and polymer (B'). (However, polymer (A) excludes polymer (B).) Polymer (A): A polyamic acid (A) having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, As the structural unit derived from a tetracarboxylic acid derivative, the following formula (1T ａ ) a structural unit (a-1Ta) represented by As the structural unit derived from diamine, the following formula (1D ａ The polyamic acid described above, which contains a structural unit (a-1Da) represented by the formula: Polymer (B): A polyamic acid (B) having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, As the structural unit derived from a tetracarboxylic acid derivative, the following formula (1T ｂ ) structural unit (b-1Tb) represented by As the structural unit derived from diamine, the following formula (1D ｂ ) structural unit (b-1Db) represented by At least a portion of the terminals of the polyamic acid (B) contain a non-amino group, and the non-amino group is a functional group represented by the following structural formula (E): The polyamic acid (B) as described above, wherein the proportion of terminal amino groups present in the polyamic acid (B) is 60% or less based on all terminals of the polyamic acid (B). Polymer (B'): A polyamic acid (B') having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, As the structural unit derived from a tetracarboxylic acid derivative, the following formula (1T ｂ ) and the structural unit (b-1Tb) represented by the above formula (1T ａ ) does not contain a structural unit (a-1Da) represented by As the structural unit derived from diamine, the following formula (1D ｂ ) or a structural unit (b-1Db) represented by the following formula (1D ｂ’ ) a structural unit (b-1Db') represented by The polyamic acid (B') has terminal amino groups in an amount of more than 60% based on all terminals of the polyamic acid (B). 【Chemistry 1】 (X in the formula ａ is a tetravalent organic group represented by the following formula (x-2), or a tetravalent organic group having an alicyclic structure of five or more members (T ５ａ ) is represented by the formula (1D ａ ) in Y ａ represents a divalent organic group derived from a diamine. Each Z independently represents a hydrogen atom or a monovalent organic group. 【Chemistry 2】 【Transformation 3】 (X in the formula ｂ represents a tetravalent organic group derived from an aromatic tetracarboxylic dianhydride. ｂ ) in Y ｂ is diamine (0) "H-N(Z)-Ar １ -L １ -A-L １’ -Ar １’ -N(Z)-H" or diamine(0') "H-N(Z)-Ar ２ -L ２ -A ２ -L ２’ -Ar ２’ represents a divalent organic group derived from "-N(Z)-H". １ , Ar １’ each independently represents a benzene ring, a biphenyl structure, or a naphthalene ring. １ , Ar １’ Any hydrogen atom on the ring may be substituted with a monovalent group. A represents a divalent organic group having an alkylene structure and having 1 to 10 carbon atoms. L １ , L １’ each independently represents a single bond, —O—, —S—, —C(═O)—, —O—C(═O)—, —NR— (R represents a hydrogen atom or a monovalent organic group), —C(═O)—NR— (R represents a hydrogen atom or a monovalent organic group), or —NR—C(═O)— (R represents a hydrogen atom or a monovalent organic group). Ar ２ and Ar ２’ each independently represents a benzene ring, a biphenyl structure, a naphthalene ring, or an aromatic heterocycle. ２ and Ar ２’ Any hydrogen atom on the ring of A may be substituted with a monovalent group. ２ represents a divalent organic group having an alkylene group. L ２ , L ２’ each independently represents a single bond, —O—, —S—, —C(═O)—, —O—C(═O)—, —NR— (R represents a hydrogen atom or a monovalent organic group), —C(═O)—NR— (R represents a hydrogen atom or a monovalent organic group), or —NR—C(═O)— (R represents a hydrogen atom or a monovalent organic group). However, Ar ２ and Ar ２’ and A ２ Any of the following has a heterocyclic ring. Z is the above formula (1D ａ ) is synonymous with Z in 【Chemistry 4】 (In formula (E), Q is a monovalent organic group selected from the following groups (e1) to (e3). * represents a bond.) (e1) Acyclic hydrocarbon group having 1 to 6 carbon atoms (e2) A monovalent organic group having 1 or 2 carboxy groups and 2 to 30 carbon atoms (however, the monovalent organic group does not include an acid anhydride group). (e3) A monovalent organic group having two or more Boc groups and having 1 to 30 carbon atoms excluding Boc, the monovalent organic group being, for example, *1-NH(Boc), *1-N(Boc), ２ and "*1-N(Boc)-*1" (*1 represents a bond bonded to a carbon atom). When there are two or more protected amino moieties, the respective protected amino moieties may be the same or different. 【Transformation 5】 (Formula (1D ｂ’ ) in Y ｂ’ is a diamine (1) "H-N(Z)-Ar ３ represents a divalent organic group derived from the group consisting of Ar, Ar(Z), ... ３ is -Ar ４ -NR １ -Ar ４’ -, -Ar ４１ -Ar ４２ -, or three or more cyclic groups selected from the group consisting of a benzene ring and a heterocycle are directly or ２ represents a divalent organic group linked via -, and the divalent organic group is bonded to two -N(Z)- via aromatic carbon atoms contained in a benzene ring or a heterocycle, and the two aromatic carbon atoms are not contained in the same cyclic group. Ar ４ and Ar ４’ respectively represent a benzene ring or an aromatic heterocycle. Ar ４１ and Ar ４２ each represents a benzene ring or an aromatic heterocycle, and Ar ４１ and Ar ４２ One of the groups represents a benzene ring, and the other represents an aromatic heterocycle. Ar ３ Any hydrogen atom on the benzene ring or aromatic heterocycle of Ar １ , Ar １’ It may be substituted with a monovalent group exemplified by the following. -NR １ -, -NR ２ R in - １ , R ２ , represents a hydrogen atom or a monovalent organic group.

2. The liquid crystal aligning agent according to claim 1, wherein the (e1) is a residue derived from an acyclic aliphatic dicarboxylic acid anhydride.

3. The (e2) has a residue derived from a dicarboxylic acid anhydride, and is a monovalent organic group having 1 to 2 carboxy groups (however, the monovalent organic group does not include an acid anhydride group), and the dicarboxylic acid anhydride is selected from a compound (e2-1) not having an alkoxysilane structure, or a compound (e2-2) having an alkoxysilane structure. The liquid crystal aligning agent according to claim 1.

4. The liquid crystal aligning agent according to claim 3, wherein the compound (e2-1) is an aromatic or aliphatic cyclic dicarboxylic acid anhydride.

5. The compound (e2-2) is 4-(3-trimethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-triethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-trimethoxysilylpropyl)phthalic anhydride, 4-(3-triethoxysilylpropyl)phthalic anhydride, (C1 to C6)alkoxydimethylsilyl(C2 to C8)alkyl succinic anhydride; di(C1 to C6)alkoxymethylsilyl(C2 to C8) ) alkyl succinic anhydride; tri(C1-6)alkoxysilyl(C2-8) alkyl succinic anhydride; 4-(3-dimethylmethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-dimethylethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-dimethylmethoxysilylpropyl)phthalic anhydride or 4-(3-dimethylethoxysilylpropyl)phthalic anhydride, the liquid crystal aligning agent according to claim 3, selected from.

6. The liquid crystal aligning agent according to claim 1, wherein the (e3) is obtained using an active ester compound (e) represented by R-O-C(=O)-E3 (E3 represents the (e3). R represents an active ester forming group).

7. E3 is a group obtained by removing a carboxy group from a carboxylic acid (W) represented by "W-COOH" (W has the same meaning as in formula (e3)), The liquid crystal aligning agent according to claim 6, wherein the carboxylic acid (W) is obtained by protecting an amino group of a carboxyl group-containing polyamine (pA) having two or more amino groups.

8. *-L in the diamine (0) １ -A-L １’ The liquid crystal aligning agent according to claim 1, wherein -* is selected from the following embodiments: (In the following formula, * represents Ar １ or Ar １’ is the bond that bonds to n is an integer from 1 to 10. m1 and m2 each independently represent an integer of 0 to 4; n' represents an integer of 1 to 6; the sum of m1, m2 and n' is 1 to 8. *-O-(CH ２ ) ｎ１ -O-(CH ２ ) ｎ２ In -O-*, n1 and n2 each independently represent an integer of 1 to 6, and the sum of n1 and n2 is 2 to 10. *-(CH ２ ) ｎ１ -NR-C(=O)-NR-(CH ２ ) ｎ２ -In *, n1 and n2 are each independently an integer of 1 to 6, and the sum of n1 and n2 is 2 to 9. Furthermore, R represents a hydrogen atom or a monovalent organic group. When two Rs are present, each independently has the above definition. *-(CH) ２ ) ｎ -*、-O-(CH ２ ) ｎ -O-*、 *-O-(CH ２ ) ｎ１ -O-(CH ２ ) ｎ２ -O-*、 *-C(=O)-(CH ２ ) ｎ -C(=O)-*、 *-C(=O)-NR-(CH ２ ) ｎ -O-*、 *-O-C(=O)-(CH ２ ) ｎ -O-*、 *-O-C(=O)-(CH ２ ) ｎ -O-C(=O)-*、 *-O-C(=O)-(CH ２ ) ｎ -C(=O)-O-*、 *-(CH ２ ) ｍ１ -O-C(=O)-(CH ２ ) ｎ’ -C(=O)-O-(CH ２ ) ｍ２ -* *-S-(CH ２ ) ｎ -S-*、 *-C(=O)-NR-(CH ２ ) ｎ -NR-C(=O)-*、 *-C(=O)-O-(CH ２ ) ｎ -O-C(=O)-*、 *-(CH ２ ) ｍ１ -C(=O)-O-(CH ２ ) ｎ’ -O-C(=O)-(CH ２ ) ｍ２ -* *-O-(CH ２ ) ｎ -*、*-S-(CH ２ ) ｎ -*、 *-NR-C(=O)-(CH ２ ) ｎ -C(=O)-NR-* *-(CH ２ ) ｎ１ -NR-C(=O)-NR-(CH ２ ) ｎ２ -* *-(CH ２ ) ｎ１ -NR-(CH ２ ) ｎ２ -*、 *-(CH ２ ) ｍ１ -C(=O)-NR-(CH ２ ) ｎ’ -NR-C(=O)-(CH ２ ) ｍ２ -*、 *-(CH ２ ) ｍ１ -NR-C(=O)-(CH ２ ) ｎ’ -C(=O)-NR-(CH ２ ) ｍ２ -*

9. 2. The liquid crystal aligning agent according to claim 1, wherein the polyamic acid (A) and / or the polyamic acid (B) is a diamine in a diamine-derived structural unit, and the diamine, excluding a diamine having a thermally detachable group, is a diamine having no side chain group having 3 or more carbon atoms.

10. A liquid crystal aligning agent capable of forming a liquid crystal alignment film having a pretilt angle of 0° or more and less than 3°, and a change in pretilt angle represented by the following formula 1 of less than 0.3°, the liquid crystal aligning agent comprising the following polymer (A) and polymer (B), or polymer (B) and polymer (B'). (However, polymer (A) excludes polymer (B) and polymer (B)'.) Polymer (A): A polyamic acid (A) having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, As the structural unit derived from a tetracarboxylic acid derivative, the following formula (1T ａ ) a structural unit (a-1Ta) represented by As the structural unit derived from diamine, the following formula (1D ａ The polyamic acid described above, which contains a structural unit (a-1Da) represented by the formula: Polymer (B): A polyamic acid (B) having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, As the structural unit derived from a tetracarboxylic acid derivative, the following formula (1T ｂ ) structural unit (b-1Tb) represented by As the structural unit derived from diamine, the following formula (1D ｂ ) structural unit (b-1Db) represented by The polyamic acid (B), wherein at least a portion of the terminals of the polyamic acid (B) contain a non-amino group, and the non-amino group is a functional group represented by the following structural formula (E): Polymer (B'): A polyamic acid (B') having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, As the structural unit derived from a tetracarboxylic acid derivative, the following formula (1T ｂ ) and the structural unit (b-1Tb) represented by the above formula (1T ａ ) does not contain a structural unit (a-1Da) represented by As the structural unit derived from diamine, the following formula (1D ｂ ) or a structural unit (b-1Db) represented by the following formula (1D ｂ’ ) a structural unit (b-1Db') represented by The polyamic acid (B') has terminal amino groups in an amount of more than 60% based on all terminals of the polyamic acid (B). 【Transformation 6】 (X in the formula ａ is a tetravalent organic group represented by the following formula (x-2), or a tetravalent organic group having an alicyclic structure of five or more members (T ５ａ ) is represented by the formula (1D ａ ) in Y ａ represents a divalent organic group derived from a diamine. Each Z independently represents a hydrogen atom or a monovalent organic group. 【Transformation 7】 【Transformation 8】 (X in the formula ｂ represents a tetravalent organic group derived from an aromatic tetracarboxylic dianhydride. ｂ ) in Y ｂ is diamine (0) "H-N(Z)-Ar １ -L １ -A-L １’ -Ar １’ -N(Z)-H" or diamine(0') "H-N(Z)-Ar ２ -L ２ -A ２ -L ２’ -Ar ２’ represents a divalent organic group derived from "-N(Z)-H". １ , Ar １’ each independently represents a benzene ring, a biphenyl structure, or a naphthalene ring. １ , Ar １’ Any hydrogen atom on the ring may be substituted with a monovalent group. A represents a divalent organic group having an alkylene structure and having 1 to 10 carbon atoms. L １ , L １’ each independently represents a single bond, —O—, —S—, —C(═O)—, —O—C(═O)—, —NR— (R represents a hydrogen atom or a monovalent organic group), —C(═O)—NR— (R represents a hydrogen atom or a monovalent organic group), or —NR—C(═O)— (R represents a hydrogen atom or a monovalent organic group). Ar ２ and Ar ２’ each independently represents a benzene ring, a biphenyl structure, a naphthalene ring, or an aromatic heterocycle. ２ and Ar ２’ Any hydrogen atom on the ring of A may be substituted with a monovalent group. ２ represents a divalent organic group having an alkylene group. L ２ , L ２’ each independently represents a single bond, —O—, —S—, —C(═O)—, —O—C(═O)—, —NR— (R represents a hydrogen atom or a monovalent organic group), —C(═O)—NR— (R represents a hydrogen atom or a monovalent organic group), or —NR—C(═O)— (R represents a hydrogen atom or a monovalent organic group). However, Ar ２ and Ar ２’ and A ２ Any of the following has a heterocyclic ring. Z is the above formula (1D ａ ) is synonymous with Z in 【Chemistry 9】 (In formula (E), Q is a monovalent organic group selected from the following groups (e1) to (e3). * represents a bond.) (e1) Acyclic hydrocarbon group having 1 to 6 carbon atoms (e2) A monovalent organic group having 1 or 2 carboxy groups and 2 to 30 carbon atoms (however, the monovalent organic group does not include an acid anhydride group). (e3) A monovalent organic group having two or more Boc groups and having 1 to 30 carbon atoms excluding Boc, the monovalent organic group being, for example, *1-NH(Boc), *1-N(Boc), ２ and "*1-N(Boc)-*1" (*1 represents a bond bonded to a carbon atom). When there are two or more protected amino moieties, the respective protected amino moieties may be the same or different. 【Chemistry 10】 (Formula (1D ｂ’ ) in Y ｂ’ is a diamine (1) "H-N(Z)-Ar ３ represents a divalent organic group derived from the group consisting of Ar, Ar(Z), ... ３ is -Ar ４ -NR １ -Ar ４’ -, -Ar ４１ -Ar ４２ -, or three or more cyclic groups selected from the group consisting of a benzene ring and a heterocycle are directly or ２ represents a divalent organic group linked via -, and the divalent organic group is bonded to two -N(Z)- via aromatic carbon atoms contained in a benzene ring or a heterocycle, and the two aromatic carbon atoms are not contained in the same cyclic group. Ar ４ and Ar ４’ respectively represent a benzene ring or an aromatic heterocycle. Ar ４１ and Ar ４２ each represents a benzene ring or an aromatic heterocycle, and Ar ４１ and Ar ４２ One of the groups represents a benzene ring, and the other represents an aromatic heterocycle. Ar ３ Any hydrogen atom on the benzene ring or aromatic heterocycle of Ar １ , Ar １’ It may be substituted with a monovalent group exemplified by the following. -NR １ -, -NR ２ R in - １ , R ２ , represents a hydrogen atom or a monovalent organic group. [Formula 1] Δ=|Δb−Δa| Δ: Change in pretilt angle after 48 hours of storage at room temperature Δa: Pretilt angle of the liquid crystal cell Δb: Pretilt angle of a liquid crystal cell using the same liquid crystal alignment agent after being left at room temperature for 48 hours (In the above formula 1, the pretilt angle represents a value measured in a state where no voltage is applied to a liquid crystal cell obtained using two substrates with liquid crystal alignment films.)

11. A method for producing a liquid crystal alignment film, comprising: applying the liquid crystal aligning agent according to any one of claims 1 to 10 to a substrate; baking the applied liquid crystal aligning agent; and irradiating the resulting film with polarized radiation.

12. The method for producing a liquid crystal alignment film according to claim 11, wherein the baking temperature is 150 to 250°C.

13. A liquid crystal alignment film formed from the liquid crystal aligning agent according to any one of claims 1 to 10.

14. A liquid crystal display device comprising the liquid crystal alignment film according to claim 13.

15. 15. The liquid crystal display element according to claim 14, which is of an IPS drive system or an FFS drive system.

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