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

Abstract

To provide a liquid crystal orientation agent containing two or more kinds of polyamic acids, in which the amide exchange reaction is suppressed and the resistance against an AC residual image is excellent, a liquid crystal orientation film obtained from the liquid crystal orientation agent, and a liquid crystal display element.SOLUTION: A liquid crystal orientation agent containing two or more kinds of polyimide precursors, in which the amide exchange reaction is suppressed and the resistance against an AC residual image is excellent, a liquid crystal orientation film, and a liquid crystal display element are provided. The liquid crystal orientation agent contains a polymer component (P) containing two or more kinds of polymers and a component (C). The polymer component (P) satisfies at least one of particular conditions (i) to (iii). When the total components in the liquid crystal orientation agent is 100 mass%, the content of the component (C) is 0.1 mass% or more and less than 11 mass% and the component (C) is a compound having 1 to 5 carbons with 1 or 2 hydroxy groups.SELECTED DRAWING: None

Description

[Technical field]

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

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

[0003] At present, the most widely used liquid crystal alignment film industrially is produced by rubbing the surface of a film made of a polymer, typically polyamic acid and / or polyimide obtained by imidizing the polyamic acid, formed on an electrode substrate in one direction with a cloth such as cotton, nylon, or polyester, a so-called rubbing process (see, for example, Patent Document 1). The rubbing process is an industrially useful method that is simple and has excellent productivity. On the other hand, as liquid crystal display elements have become higher in performance, higher in definition, and larger in size, a photoalignment method that imparts liquid crystal alignment ability by irradiating polarized radiation has been known as an alignment method that replaces the rubbing process. As for the photoalignment method, methods that utilize a photoisomerization reaction, a photocrosslinking reaction, a photodecomposition reaction, and the like have been proposed (see, for example, Patent Document 2 and Non-Patent Document 1). In addition, liquid crystal aligning agents that contain two or more types of polyamic acids with different properties are known as liquid crystal aligning agents that form liquid crystal alignment films. It is known that such liquid crystal aligning agents undergo amide exchange reactions during preparation and storage, resulting in the averaged polymer composition (see, for example, Patent Document 3). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] WO2016 / 063834 publication [Patent Document 2] Japanese Patent Publication No. 2011-107266 [Patent Document 3] WO2012 / 057337 publication [Non-patent literature]

[0005] [Non-Patent Document 1] "Liquid Crystal Photo-Alignment Film" Kidowaki, Ichimura, Functional Materials, November 1997, Vol. 17, No. 11, pp. 13-22 Summary of the Invention [Problem to be solved by the invention]

[0006] In recent years, large-screen, high-definition liquid crystal display elements have become mainstream, and small display terminals such as smartphones, tablet PCs, and car navigation systems have become more widespread, so the demand for higher quality liquid crystal display elements is increasing more than ever before. In particular, liquid crystal alignment films used in liquid crystal display elements, such as those in the IPS and FFS modes, require high alignment control power to suppress image retention (hereinafter referred to as AC image retention) that occurs due to long-term AC driving. When a liquid crystal alignment agent containing two or more kinds of polyamic acids with different properties is used, it is preferable from the viewpoint of production costs. However, problems occur in that the amide exchange reaction occurs, and therefore it is not always possible to obtain a material that meets the high level requirements as described above.

[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 amide exchange reaction and has excellent resistance to AC image retention, a liquid crystal alignment film obtained from the liquid crystal alignment agent, and a liquid crystal display element. [Means for solving the problem]

[0008] Means for Solving the Problems The present inventors have conducted intensive research to achieve the above object, and as a result have found that use of a liquid crystal aligning agent containing a first polyimide precursor having a structural unit having a specific tetracarboxylic acid residue, a second polyimide precursor having a specific tetracarboxylic acid residue, and a specific compound having a hydroxy group 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 comprising a polymer component (P) containing two or more polymers, and a component (C), The polymer component (P) satisfies at least one of the following conditions (i) to (iii): The liquid crystal aligning agent, wherein the content of the component (C) is 0.1% by mass or more and less than 11% by mass, when the total amount of all components in the liquid crystal aligning agent is 100% by mass. (i) A polymer component (P1) having one or more types of structural units and including two or more types of polyimide precursors (A) having a structural unit (a1) represented by the following formula (A1): (ii) A polymer component (P2) which is a polymer different from the polyimide precursor (A) and has one or more types of structural units and contains two or more types of polyimide precursors (B) having a structural unit (b1) represented by the following formula (B1): (iii) A polymer component (P3) containing the polyimide precursor (A) and the polyimide precursor (B). [ka] (In formula (A1), X a1 represents a tetravalent organic group selected from the group consisting of the following formulas (Xa1-1) to (Xa1-8), and Y a1 represents a divalent organic group. [ka] (In formulae (Xa1-1) to (Xa1-3), R1 to R 15each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, or a phenyl group, and may be the same or different. * represents a bond.) [ka] (In formula (B1), X b1 represents a tetravalent organic group having an aromatic group having 6 to 30 carbon atoms; b1 At least one of the carbonyl carbons bonded to X b1 It bonds to the aromatic group of Y. b1 represents a divalent organic group. Component (C): A compound (C) having 1 to 5 carbon atoms and 1 or 2 hydroxy groups. Throughout this specification, the following terms and abbreviations have the following meanings: Halogen atom includes a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like. In each case, * represents a bond. In addition, Boc represents a tert-butoxycarbonyl group, and Fmoc represents a 9-fluorenylmethoxycarbonyl group. Effect of the Invention

[0010] According to the present invention, it is possible to obtain a liquid crystal alignment agent containing two or more kinds of polyimide precursors, which suppresses amide exchange reaction and has excellent resistance to AC afterimages, a liquid crystal alignment film obtained from the liquid crystal alignment agent, and a liquid crystal display element. In addition, the liquid crystal display element has high display quality with few display defects. The mechanism by which the above-mentioned effects of the present invention are obtained is not entirely clear, but is generally presumed to be as follows: By adding a compound having a hydroxy group, the environment around the carboxylic acid in the amic acid is changed, and the amide exchange reaction is suppressed, which allows the polyimide precursor, which has excellent liquid crystal alignment ability, to exhibit its inherent function, thereby obtaining the above-mentioned effects. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] <Polymer component (P)> The polymer component (P) contained in the liquid crystal aligning agent of the present invention is a polymer component that contains two or more kinds of polymers and satisfies at least one of the following conditions (i) to (iii). (i) A polymer component (P1) having one or more types of structural units and including two or more types of polyimide precursors (A) having the structural unit (a1) represented by the above formula (A1). (ii) A polymer component (P2) which is a polymer different from the polyimide precursor (A), has one or more types of structural units, and contains two or more types of polyimide precursors (B) having the structural unit (b1) represented by the above formula (B1). (iii) A polymer component (P3) containing the polyimide precursor (A) and the polyimide precursor (B).

[0012] <Polyimide precursor (A)> The polymer components (P1) and (P3) contained in the liquid crystal alignment agent of the present invention contain a polyimide precursor (A) having one or more structural units and having a structural unit (a1) represented by the following formula (A1). The polyimide precursor (A) may be one or more polymers. The polyimide precursor (A) may have one type of structural unit, or may have two or more different structural units, or may have three or more different structural units, or may have four or more different structural units. [ka] (In formula (A1), X a1 represents a tetravalent organic group selected from the group consisting of the following formulas (Xa1-1) to (Xa1-8), and Y a1 represents a divalent organic group. [ka] In formulae (Xa1-1) to (Xa1-3), R1 to R 15each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, or a phenyl group, and may be the same or different. * represents a bond.

[0013] Above R1~R 15 Specific examples of the alkyl group having 1 to 6 carbon atoms in the above R1 to R2 include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, and an n-pentyl group. 15 Specific examples of the alkenyl group having 2 to 6 carbon atoms in R1 to R2 include a vinyl group, a propenyl group, and a butenyl group, which may be linear or branched. 15 Specific examples of the alkynyl group having 2 to 6 carbon atoms in the above R1 to R2 include an ethynyl group, a 1-propynyl group, a 2-propynyl group, a 1-butynyl group, a 2-butynyl group, and a 3-butynyl group. 15 In the above formula, examples of the monovalent organic group having 1 to 6 carbon atoms and containing a fluorine atom include a fluoromethyl group, a trifluoromethyl group, a pentafluoroethyl group, and a pentafluoropropyl group. From the viewpoint of the alignment of liquid crystal and the reliability of liquid crystal display elements, the above X a1 is preferably a tetravalent organic group represented by the above formula (Xa1-1). Furthermore, from the viewpoint of high photoreactivity, R1 to R4 are each independently a hydrogen atom or a methyl group, and it is preferable that at least one of R1 to R4 is a methyl group, and it is more preferable that at least two of R1 to R4 are methyl groups. It is even more preferable that R1 and R4 are methyl groups, and R2 and R3 are hydrogen atoms. The above formula (Xa1-1) is preferably a tetravalent organic group selected from the group consisting of the following formulae (Xa1-1-1) to (Xa1-1-5). [ka]

[0014] Y in the above formula (A1) a1The divalent organic group is not particularly limited, and examples thereof include divalent organic groups represented by the following formulas (3) to (4): The divalent organic group is introduced into the structural unit of the polyimide precursor (A) by using a diamine having the divalent organic group as a diamine component for obtaining the polyimide precursor (A). From the viewpoint of suitably obtaining the effects of the present invention, at least one of the structural units constituting the polyimide precursor (A) preferably has a structure selected from the group consisting of divalent organic groups represented by the following formulas (3) to (4), and more preferably has a structure selected from the group consisting of divalent organic groups represented by the following formulas (3) to (4) in which * is bonded to a nitrogen atom derived from a diamine. In order to preferably obtain the effects of the present invention, in the above formula (A1), Y a1 is preferably a divalent organic group selected from the group consisting of the following formulas (3) to (4). [ka] (In formulas (3) and (4), R3, R4, and R 4’ each independently represents a halogen atom, a hydroxy group, an optionally protected amino group, a thiol group, a nitro group, a phosphate group, or a monovalent organic group having 1 to 20 carbon atoms. A4 represents an ester bond, an amide bond, a thioester bond, or a divalent organic group having 2 to 20 carbon atoms, provided that a 1,4-phenylene group, 1 to 4 of the hydrogen atoms on the phenylene group are R4, and R 4’ This excludes divalent organic groups substituted with, or divalent organic groups in which such divalent organic groups are linked together. a3, a4, and a4' each independently represents an integer of 0 to 4. a is an integer of 1 to 4. b and c are each independently an integer of 1 to 2. R3, R4, R 4’ When there are multiple R3, R4, and R 4’ may be the same or different. When a3, a4, and a4' are present in plural, they may be the same or different. * represents a bond.)

[0015] R3, R4, and R in the above formulas (3) and (4) 4’ In the above formula, the monovalent organic group having 1 to 20 carbon atoms is a monovalent hydrocarbon group having 1 to 20 carbon atoms, and any methylene group of the hydrocarbon group may be -O-, -S-, -C(=O)-, -C(=O)-O-, -C(=O)-S-, -NR 3 -(However, R 3 represents a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, or a tert-butoxycarbonyl group, —CO—NR 3 -(However, R 3 represents a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, or a tert-butoxycarbonyl group. 3 )2-(where R 3 represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms.) or -S(=O)2- or the like (hereinafter, these groups are also referred to as heteroatom-containing group (A)); a monovalent group (A2) in which at least one hydrogen atom bonded to a carbon atom of a monovalent hydrocarbon group or a monovalent group A is substituted with a halogen atom, a hydroxy group, an alkoxy group, a nitro group, an amino group which may be protected by a protecting group, a mercapto group, a nitroso group, an alkylsilyl group, an alkoxysilyl group, a silanol group, a sulfino group, a phosphino group, a carboxy group, a cyano group, a sulfo group, an acyl group or the like; and a monovalent group having a heterocycle. The number of carbon atoms in the group (A), the group (A2) and the monovalent group having a heterocycle is 1 to 20. R3, R4, and R 4’ As the monovalent organic group having 1 to 20 carbon atoms, among others, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, and a monovalent group obtained by replacing any methylene group of the hydrocarbon group with the hetero atom-containing group (A) described above are more preferable. The optionally protected amino group includes -N(R)2, where R represents a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, or a tert-butoxycarbonyl group. R3, R4, and R 4’The monovalent organic group having 1 to 20 carbon atoms in the formula (I) is preferably a methyl group, a methoxy group, a vinyl group, a halogen atom, a hydroxy group, an amino group which may be protected by a protecting group, or a monovalent group in which at least one hydrogen atom of an alkyl group having 1 to 3 carbon atoms has been substituted with a halogen atom or an amino group which may be protected by a protecting group.

[0016] In the above formula (3), a is preferably an integer of 1 to 2. In the above formula (3), a3 is preferably an integer of 0 to 2, and when a plurality of a3's are present, they may be the same or different. In the above formula (4), a4 and a4' are each independently preferably an integer of 0 to 2, and when a plurality of a4's are present, they may be the same or different.

[0017] The divalent organic group having 2 to 20 carbon atoms in A4 of the above formula (4) is a hydrocarbon group having 2 to 20 carbon atoms; any alkylene group contained in the hydrocarbon group may be -C(=O)-, -NR-, -C(=O)-O-, -Si(R 0 )2-, and at least one of -OC(=O)- (provided that the divalent organic group (4a) has 2 to 20 carbon atoms); a divalent organic group (4b) in which -O- is inserted at at least one position between an end of a hydrocarbon group having 2 to 20 carbon atoms and a carbon-carbon bond of any alkylene group contained in the hydrocarbon group; a divalent organic group (4c) in which -O- is inserted at at least one position between a carbon-carbon bond of any alkylene group contained in the divalent organic group (4a); and a divalent organic group (4d) having 2 to 20 carbon atoms and having a heterocycle. R in the above-mentioned -NR- represents a hydrogen atom, a monovalent hydrocarbon group having 1 to 5 carbon atoms, or a tert-butoxycarbonyl group. 0 )2-R in 0 represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms.

[0018] Examples of the hydrocarbon group include a chain hydrocarbon group, an alicyclic hydrocarbon group, or a hydrocarbon group having an aromatic group (examples of the aromatic ring structure in the aromatic group include a benzene ring, a naphthalene ring, a biphenyl structure, an anthracene ring, etc.). Specific examples of the chain hydrocarbon group include a divalent linear or branched hydrocarbon group having 1 to 20 carbon atoms not having a cyclic structure, and are preferably an alkylene group having 1 to 20 carbon atoms, an alkenylene group having 2 to 20 carbon atoms, or an alkynylene group having 2 to 20 carbon atoms. Specific examples of the alicyclic hydrocarbon group include an alicyclic structure (for example, a cyclohexylene group or a bicyclohexylene group), or a hydrocarbon group having an alicyclic structure and a chain hydrocarbon structure. Specific examples of the hydrocarbon group having an aromatic group include an aromatic group, a hydrocarbon group having an aromatic group and a chain hydrocarbon structure, and a hydrocarbon group having an aromatic group and an alicyclic structure.

[0019] The heterocycle in the divalent organic group (4d) can be a piperidine ring, a piperazine ring, a morpholine ring, a pyrrolidine ring, a pyrrole ring, a furan ring, a thiophene ring, an imidazole ring, a pyrazole ring, an imide ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, a pyridine ring, a pyrimidine ring, a pyridazine ring, or a pyrazine ring, or a condensed ring containing these ring structures as a part of the structure, and the hydrogen atom on the ring can be substituted.The substituent can be a halogen atom, a methyl group, or a methoxy group, and the like.

[0020] In order to preferably obtain the effects of the present invention, A4 in the above formula (4) is preferably a group "-L1-AL 1’ -" or a divalent organic group having 2 to 20 carbon atoms and a heterocycle is preferred. In addition, the group "-L1-AL 1’ -" in L1, L 1’ and the total number of carbon atoms in A is 2 to 20. L1 and L 1’each independently represents a single bond, -O-, -NR-, -C(=O)-NR-, -C(=O)-, or -OC(=O)-, and R represents a hydrogen atom, a monovalent hydrocarbon group having 1 to 5 carbon atoms, or a tert-butoxycarbonyl group. Base “-L1-AL 1’ In order to favorably obtain the effects of the present invention, A in "-" is preferably an alkylene group having 1 to 12 carbon atoms, -CH=CH-, -C≡C-, -CR0=CR 0’ -C(=O)-O-(R0 and R 0’ each independently represents a hydrogen atom or a methyl group; or between the carbon-carbon bonds of the alkylene group, -O-, -NR-, -C(=O)-NR-, -C(=O)-NR-C(=O)-, -C(=O)-O-, -Si(R a represents a divalent organic group having at least one of the groups -O-Ar-O-, -OC(=O)-Ar-C(=O)-O-, and -C(=O)-O-Ar-OC(=O)-. 1’ represents a single bond, A represents a group other than a methylene group. R in the above -C(=O)-NR- and -C(=O)-NR-C(=O)- represents a hydrogen atom, a monovalent hydrocarbon group having 1 to 5 carbon atoms, or a tert-butoxycarbonyl group. a )2-R in a represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 3 carbon atoms. Any hydrogen atom possessed by A may be substituted with a halogen atom. In the above-mentioned -O-Ar-O-, -OC(=O)-Ar-C(=O)-O-, and -C(=O)-O-Ar-OC(=O)-, Ar represents a phenylene group or a biphenyl structure.

[0021] More preferred specific examples of the above formulae (3) and (4) include the following formula (d AL -1)~(d AL Examples of the structures represented by the following formula (d AL -1)~(dAL In the structures represented by the following formula (d AL -9) The bonding positions of all benzene rings are 1,4-positions. [ka] (Formula(d AL In formula (d-6), when m1 and m2 are 0, the sum of m1, m2 and n is 1 to 12, and when at least one of m1 and m2 is an integer other than 0, the sum of m1, m2 and n is 2 to 12. AL In formula (d-8), the sum of m1, m2 and n is 3 to 12. AL -11) and formula (d AL -12) The sum of m1, m2 and n is 3 to 12. [ka] [ka] [ka] [ka] [ka]

[0022] In addition, Y in the above formula (A1) a1 The divalent organic group may have a structure other than the divalent organic groups represented by the above formulas (3) to (4). Other structures include a divalent organic group (3L) in which the bonding position of the benzene ring bonded to * in the above formula (3) is changed from 1,4-position to 2,5-position; a divalent organic group (4L) in which at least one bonding position of the benzene ring bonded to * in the above formula (4) is changed from 1,4-position to 2,5-position; or a divalent organic group obtained by removing two amino groups from the following diamines. Note that in the above divalent organic groups (3L) and (4L), R3, R4, R 4’ The preferred embodiments of A4, a3, a4, a4', a, b, and c are the same as those in the above formulae (3) and (4).

[0023] Aromatic diamines having a naphthalene ring, such as 1,2-bis(6-amino-2-naphthyloxy)ethane, 1,2-bis(6-amino-2-naphthyl)ethane, or 6-[2-(4-aminophenoxy)ethoxy]-2-naphthylamine, 4,4'-diaminoazobenzene, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 4,4'- Diaminobenzophenone, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, 3,6-diaminoacridine, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, 4,4'-diaminodiphenylamine, 4,4'-diaminodiphenyl-N-methylamine, 4-(2-(methylamino)ethyl)aniline, 4-(2-aminoethyl)aniline, 1-(4-aminophenyl)- Steroid skeleton compounds such as 1,3,3-trimethyl-1H-indan-5-amine, 1-(4-aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H-inden-6-amine, cholestanyloxy-3,5-diaminobenzene, cholestanyloxy-3,5-diaminobenzene, cholestanyloxy-2,4-diaminobenzene, cholestanyl 3,5-diaminobenzoate, cholestanyl 3,5-diaminobenzoate, lanostannyl 3,5-diaminobenzoate, and 3,6-bis(4-aminobenzoyloxy)cholestane. diamines having a siloxane bond such as 1,3-bis(3-aminopropyl)-tetramethyldisiloxane; meta-xylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, 1,3-bis(aminomethyl)cyclohexane, 1,4-diaminocyclohexane, 4,4'-methylenebis(cyclohexylamine), diamines in which two amino groups are bonded to a group represented by any one of formulas (Y-1) to (Y-167) described in WO2018 / 117239, and the like.

[0024] From the viewpoint of suitably obtaining the effects of the present invention, the polyimide precursor (A) may be a polyimide precursor having, in addition to the structural unit (a1) represented by the above formula (A1), a structural unit (a2) represented by the following formula (A2): [ka] (In formula (A2), X a2 represents a tetravalent organic group represented by any one of the following formulas (X-1) to (X-17) or a tetravalent organic group derived from an aromatic tetracarboxylic dianhydride, and Y a2 represents a divalent organic group. [ka] [ka]

[0025] Y in the above formula (A2) a2 Specific examples of the divalent organic group include Y in the above formula (A1). a1 The structures exemplified as divalent organic groups include preferred embodiments thereof. From the viewpoint of reducing afterimages resulting from residual DC, the polyimide precursor (A) may be a polymer containing a structural unit having a divalent organic group selected from the group consisting of a divalent organic group having a urea bond; a divalent organic group having an amide bond; a divalent organic group having at least one nitrogen atom-containing structure selected from the group consisting of a nitrogen atom-containing heterocycle, a secondary amino group, and a tertiary amino group; and a divalent organic group having a carboxy group. In the above case, Y a1 , Y a2 The divalent organic group in the formula (I) is preferably a divalent organic group selected from the group consisting of a divalent organic group having a urea bond; a divalent organic group having an amide bond; a divalent organic group having at least one nitrogen atom-containing structure selected from the group consisting of a nitrogen atom-containing heterocycle, a secondary amino group, and a tertiary amino group; and a divalent organic group having a carboxy group, and preferred embodiments thereof include preferred embodiments of specific divalent organic groups described below.

[0026] The aromatic tetracarboxylic acid dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups, including at least one carboxy group bonded to an aromatic ring (such as a benzene ring or a naphthalene ring). However, it is not necessary for the aromatic ring structure to be composed only of an aromatic ring structure, and it may have a chain hydrocarbon structure or an alicyclic structure in part. A preferred specific example is an acid dianhydride represented by the following formula (X b1 -a)~(X b1 and more preferably, a tetravalent organic group represented by the following formula (X b1 -1)~(X b1 -21) is a tetravalent organic group represented by any one of the following formulas: [ka] (x and y each independently represent a single bond, an ether, a carbonyl, an ester, an alkanediyl group having 1 to 10 carbon atoms, 1,4-phenylene, a sulfonyl, or an amide bond. j and k each represent 0 or 1.) [ka] [ka]

[0027] From the viewpoint of suitably obtaining the effects of the present invention, the polyimide precursor (A) preferably contains the structural unit (a1) in an amount of 10 to 100 mol %, and more preferably 15 to 100 mol %, of all structural units contained in the polyimide precursor (A). From the viewpoint of suitably obtaining the effects of the present invention, the polyimide precursor (A) preferably contains structural units having a divalent organic group represented by the above formulas (3) to (4) in an amount of 10 to 100 mol %, and more preferably 15 to 100 mol %, of all structural units contained in the polyimide precursor (A). When the polyimide precursor (A) contains a structural unit other than the structural unit (a1), the structural unit (a1) preferably accounts for 95 mol % or less, and more preferably 90 mol % or less, of all structural units contained in the polyimide precursor (A).

[0028] <Polyimide precursor (B)> The polymer components (P2) and (P3) contained in the liquid crystal alignment agent of the present invention contain a polyimide precursor (B) which is a polymer different from the polyimide precursor (A) and has one or more structural units and has a structural unit (b1) represented by the following formula (B1). The polyimide precursor (B) may be one or more polymers. The polyimide precursor (B) may have one type of structural unit, or may have two or more different structural units, or may have three or more different structural units, or may have four or more different structural units. [ka] (In formula (B1), X b1 represents a tetravalent organic group having an aromatic group having 6 to 30 carbon atoms; b1 At least one of the carbonyl carbons bonded to X b1 It bonds to the aromatic group of Y. b1 represents a divalent organic group.

[0029] X in the above formula (B1) b1 represents a tetravalent organic group having an aromatic group having 6 to 30 carbon atoms; b1 At least one of the carbonyl carbons bonded to X b1 It is more preferably a tetravalent organic group derived from an acid dianhydride obtained by intramolecular dehydration of four carboxy groups including at least one carboxy group bonded to an aromatic ring (such as a benzene ring or a naphthalene ring). However, it is not necessary for the aromatic ring structure to be composed only of an aromatic ring structure, and it may have a chain hydrocarbon structure or an alicyclic structure as a part of the aromatic ring structure. X b1 A preferred example of X is a tetravalent organic group derived from an aromatic tetracarboxylic acid compound. b1 is preferably represented by the above formula (X b1 -a)~(X b1 -c), and more preferably, the above formula (X b1 -1)~(Xb1 -21), and more preferably, the above formula (X b1 -1)~(X b1 A tetravalent organic group represented by any one of the formulas (X -13) is more preferred. b1 -1)~(X b1 -7).

[0030] Above Y b1 As the divalent organic group in a1 From the viewpoint of reducing the afterimage caused by the residual DC, the polyimide precursor (B) is preferably a polymer containing a structural unit having a divalent organic group selected from the group consisting of a divalent organic group having a urea bond, a divalent organic group having an amide bond, a divalent organic group having at least one nitrogen atom-containing structure selected from the group consisting of a nitrogen atom-containing heterocycle, a secondary amino group, and a tertiary amino group, and a divalent organic group having a carboxy group (these are also collectively referred to as a specific divalent organic group). In addition, from the viewpoint of reducing residual images caused by residual DC, the polyimide precursor (B) is Y b1 is preferably a polymer containing a structural unit which is the specific divalent organic group. Furthermore, the above Y b1 In terms of suitably obtaining the effects of the present invention, the divalent organic group in is preferably a divalent organic group represented by the above formulas (3) to (4); or a divalent organic group obtained by removing two amino groups from a diamine selected from the group consisting of 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, and 4,4'-diaminodiphenyl ether (these are also collectively referred to as specific divalent organic group b2).

[0031] An example of the divalent organic group having a urea bond is a divalent organic group represented by the above formula (4) in which A4 has the group "-NH-C(=O)-NR-". The divalent organic group having an amide bond includes a divalent organic group represented by the above formula (4) in which A4 in the above formula (4) has an amide bond. Examples of the divalent organic group having at least one nitrogen atom-containing structure selected from the group consisting of a nitrogen atom-containing heterocycle, a secondary amino group, and a tertiary amino group include 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, 3,6-diaminoacridine, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, and the structures represented by the above formulas (z-1) to (z-7). and divalent organic groups obtained by removing two amino groups from a diamine selected from the group consisting of heterocycle-containing diamines such as diamine, and diamines having a diphenylamine structure represented by 4,4'-diaminodiphenylamine, 4,4'-diaminodiphenyl-N-methylamine, N,N'-bis(4-aminophenyl)-benzidine, N,N'-bis(4-aminophenyl)-N,N'-dimethylbenzidine, or N,N'-bis(4-aminophenyl)-N,N'-dimethyl-1,4-benzenediamine. Examples of the divalent organic group having a carboxy group include divalent organic groups obtained by removing two amino groups from a diamine having a carboxy group, such as 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 3,5-diaminobenzoic acid, 4,4'-diaminobiphenyl-3-carboxylic acid, 4,4'-diaminodiphenylmethane-3-carboxylic acid, 1,2-bis(4-aminophenyl)ethane-3-carboxylic acid, 4,4'-diaminobiphenyl-3,3'-dicarboxylic acid, 4,4'-diaminobiphenyl-2,2'-dicarboxylic acid, 3,3'-diaminobiphenyl-4,4'-dicarboxylic acid, 3,3'-diaminobiphenyl-2,4'-dicarboxylic acid, 4,4'-diaminodiphenylmethane-3,3'-dicarboxylic acid, 1,2-bis(4-aminophenyl)ethane-3,3'-dicarboxylic acid, and 4,4'-diaminodiphenylether-3,3'-dicarboxylic acid.

[0032] From the viewpoint of reducing afterimages derived from residual DC, the polyimide precursor (B) preferably contains structural units having the specific divalent organic group (more preferably structural units having the specific divalent organic group bonded to a nitrogen atom derived from a diamine) in an amount of 1 mol % or more, preferably 5 mol % or more, more preferably 10 mol % or more, and even more preferably 20 mol % or more of the total structural units contained in the polyimide precursor (B). In addition, the polyimide precursor (B) has a low residual image caused by residual DC. b1 is the specific divalent organic group, based on the total structural units contained in the polyimide precursor (B), preferably at least 1 mol %, more preferably at least 5 mol %, even more preferably at least 10 mol %, and even more preferably at least 20 mol %. Further, in order to obtain the effects of the present invention, the polyimide precursor (B) is preferably selected from the group consisting of Y b1 The structural units in which Y is the specific divalent organic group b2 are contained in the polyimide precursor (B) at 1 mol % or more, preferably 5 mol % or more, more preferably 10 mol % or more, and further preferably 20 mol % or more of the total structural units contained in the polyimide precursor (B). b1 The structural units in which b2 is the specific divalent organic group may account for 95 mol % or less, 90 mol % or less, or 80 mol % or less of all structural units contained in the polyimide precursor (B).

[0033] From the viewpoint of suitably obtaining the effects of the present invention, the polyimide precursor (B) may be a polyimide precursor having, in addition to the structural unit (b1) represented by the above formula (B1), a structural unit (b2) represented by the following formula (B2): [ka] (In formula (B2), X b2 represents a tetravalent organic group derived from an acyclic aliphatic tetracarboxylic acid dianhydride or an alicyclic tetracarboxylic acid dianhydride; Y b2 represents a divalent organic group.

[0034] Acyclic aliphatic tetracarboxylic acid dianhydrides are acid dianhydrides obtained by intramolecular dehydration of four carboxy groups bonded to a chain hydrocarbon structure. However, they do not necessarily have to be composed of a chain hydrocarbon structure alone, and may have an alicyclic structure or an aromatic ring structure in part. Alicyclic tetracarboxylic dianhydrides are acid dianhydrides obtained by intramolecular dehydration of four carboxy groups, including at least one carboxy group bonded to an alicyclic structure. However, none of these four carboxy groups are bonded to an aromatic ring. In addition, they do not necessarily have to be composed of an alicyclic structure alone, and may have a chain hydrocarbon structure or an aromatic ring structure as part of them.

[0035] X b2 From the viewpoint of suitably obtaining the effects of the present invention, is preferably a tetravalent organic group represented by any one of the above formulas (X-1) to (X-17) or (Xa1-1) to (Xa1-8).

[0036] From the viewpoint of suitably obtaining the effects of the present invention, the polyimide precursor (B) preferably contains the structural unit (b1) in an amount of 10 to 100 mol %, and more preferably 15 to 100 mol %, of all structural units contained in the polyimide precursor (B). When the polyimide precursor (B) contains a structural unit other than the structural unit (b1), the structural unit (b1) preferably accounts for 95 mol % or less, and more preferably 90 mol % or less, of all structural units contained in the polyimide precursor (B). The polyimide precursor (B) contains the structural unit (b2) in an amount of preferably 5 mol % or more, more preferably 10 mol % or more, based on the total structural units contained in the polyimide precursor (B), and preferably 90 mol % or less, more preferably 85 mol % or less, of the total structural units contained in the polyimide precursor (B).

[0037] In the polymer component (P), the mass ratio of the content of the second polyimide precursor to the content of the first polyimide precursor (content of the first polyimide precursor / content of the second polyimide precursor) is preferably 10 / 90 to 90 / 10, more preferably 20 / 80 to 90 / 10, and even more preferably 20 / 80 to 80 / 20. From the viewpoint of reducing afterimages resulting from residual DC, the mass ratio of the content of the polyimide precursor (B) to the content of the polyimide precursor (A) (content of the polyimide precursor (A) / content of the polyimide precursor (B)) is preferably 10 / 90 to 90 / 10, more preferably 20 / 80 to 90 / 10, and even more preferably 20 / 80 to 80 / 20.

[0038] <Method for producing polyimide precursor (A) and polyimide precursor (B)> The polyimide precursors (A) and (B) in the present invention can be synthesized by a known method such as that described in WO2013 / 157586.

[0039] Specifically, it can be obtained by reacting a tetracarboxylic acid derivative component containing a tetracarboxylic dianhydride with a diamine component in a solvent (condensation polymerization). The solvent is not particularly limited as long as the produced polymer can be dissolved in the solvent.

[0040] For example, when synthesizing a polyimide precursor (A) having a repeating unit represented by the above formula (A1), the diamine component may be -NH-Y a1 -NH- structure (Y a1 is Y in formula (A1). a1 The diamine having the same definition as that of the tetracarboxylic acid derivative component is represented by the above formula X a1 A tetracarboxylic dianhydride having the structure:

[0041] The ratio of the tetracarboxylic dianhydride and the diamine used in the synthesis reaction of the polyimide precursor is preferably such that the acid anhydride group of the tetracarboxylic dianhydride is 0.5 to 2 equivalents, more preferably 0.8 to 1.2 equivalents, per equivalent of the amino group of the diamine. As in the case of a normal polycondensation reaction, the closer the equivalent of the acid anhydride group of the tetracarboxylic dianhydride is to 1 equivalent, the higher the molecular weight of the polyimide precursor produced. The reaction temperature in the synthesis reaction of the polyimide precursor is preferably −20 to 150° C., more preferably 0 to 100° C. The reaction time is preferably 0.1 to 24 hours, more preferably 0.5 to 12 hours. The polyimide precursor synthesis reaction can be carried out at any concentration, but the concentration of the polyimide precursor in the reaction solution is preferably 1 to 50 mass %, more preferably 5 to 30 mass %. The reaction can be carried out at a high concentration in the early stage, and then a solvent can be added.

[0042] Specific examples of the solvent used when reacting the diamine component with the tetracarboxylic acid derivative component include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide, and 1,3-dimethyl-2-imidazolidinone. In addition, when the polymer has high solubility in the solvent, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, or H3C-CH(OH)-CH2-OD 1 (D 1 represents an alkyl group having 1 to 3 carbon atoms.) HO-CH2-CH2-OD 2 (D 2 represents an alkyl group having 1 to 3 carbon atoms.) HO-CH2-CH2-O-CH2-CH2-D 3 (D 3 represents an alkyl group having 1 to 4 carbon atoms.) These solvents may be used alone or in combination.

[0043] The above H3C-CH(OH)-CH2-OD 1 , HO-CH2-CH2-OD2 , HO-CH2-CH2-O-CH2-CH2-D 3 Specific examples of the solvent represented by the formula (I) include propylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, diethylene glycol monomethyl ether, and diethylene glycol monoethyl ether.

[0044] <Polymer solution viscosity and molecular weight> The polyimide precursor (A) and polyimide precursor (B) of the present invention preferably have a solution viscosity of, for example, 10 to 1000 mPa·s when made into a solution of 10 to 15% by mass from the viewpoint of workability, but are not particularly limited thereto. The solution viscosity (mPa·s) of the polymer is a value measured at 25°C using an E-type rotational viscometer for a polymer solution of 10 to 15% by mass prepared using a good solvent for the polymer (e.g., γ-butyrolactone, N-methyl-2-pyrrolidone, etc.).

[0045] The polyimide precursor (A) and the polyimide precursor (B) each have a weight average molecular weight (Mw) in terms of polystyrene measured by gel permeation chromatography (GPC) of preferably 1,000 to 500,000, more preferably 2,000 to 300,000. The molecular weight distribution (Mw / Mn), which is 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. From the viewpoint of suitably obtaining the effects of the present invention, it is preferable that the molecular weight is within this range.

[0046] <End-capping agent> In synthesizing the polyimide precursor (A) and polyimide precursor (B) of the present invention, a suitable terminal-capping agent may be used together with the above-mentioned tetracarboxylic acid derivative component and diamine component to form a terminal-capping polymer. The terminal-capping polymer has the effect of improving the film hardness of the liquid crystal alignment film obtained by coating and improving the adhesion property between the sealant and the liquid crystal alignment film.

[0047] Examples of the terminals of the polyimide precursor (A) and the polyimide precursor (B) in the present invention include an amino group, a carboxy group, an acid anhydride group, or derivatives thereof. The amino group, the carboxy group, and the acid anhydride group can be obtained by a normal condensation reaction or by blocking the terminals with the following terminal blocking agents, for example, they can be obtained in the same manner using the following terminal blocking agents.

[0048] Examples of the end-capping agent include acid monoanhydrides such as acetic anhydride, maleic anhydride, nadic anhydride, phthalic anhydride, itaconic anhydride, cyclohexanedicarboxylic anhydride, 3-hydroxyphthalic anhydride, trimellitic anhydride, 3-(3-trimethoxysilyl)propyl)-3,4-dihydrofuran-2,5-dione, 4,5,6,7-tetrafluoroisobenzofuran-1,3-dione, and 4-ethynylphthalic anhydride; dicarbonic acid diester compounds such as di-tert-butyl dicarbonate and diallyl dicarbonate; chlorocarbonyl compounds such as acryloyl chloride, methacryloyl chloride, and nicotinic acid chloride; aniline, 2-aminophenol, 3-aminophenol, 4 Examples of the isocyanate compounds include monoamine compounds such as 1-aminosalicylic acid, 5-aminosalicylic acid, 6-aminosalicylic acid, 2-aminobenzoic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, and n-octylamine; monoisocyanate compounds such as isocyanates having an unsaturated bond, such as ethyl isocyanate, phenyl isocyanate, naphthyl isocyanate, 2-acryloyloxyethyl isocyanate, and 2-methacryloyloxyethyl isocyanate; and isothiocyanate compounds such as ethyl isothiocyanate and allyl isothiocyanate.

[0049] The proportion of the end-capping agent used is preferably 0.01 to 20 parts by mol, and more preferably 0.01 to 10 parts by mol, based on 100 parts by mol of the total of the diamine components used.

[0050] <Compound (C)> The liquid crystal aligning agent of the present invention contains a compound (C) having 1 to 2 hydroxy groups and carbon number of 1 to 5. One type or two or more types of compounds may be used as the compound (C). Specific examples of the compound (C) include a compound (c1) in which at least one or two hydrogen atoms of an aliphatic hydrocarbon having 1 to 5 carbon atoms are replaced with a hydroxy group; a compound (c2) in which some of the secondary carbon atoms (-CH2-) bonded to two different carbon atoms of the compound (c1) are each independently replaced with -C(=O)-O- or -C(=O)-; a compound (c3-1) in which -O- is inserted between the carbon-carbon bonds of the compound (c1), or a compound (c3-2) in which -O- is inserted between the carbon-carbon bonds other than the carbonyl carbon of the compound (c2).

[0051] At least one of the carbon atoms to which one or two hydroxy groups are bonded may be a primary carbon atom, a secondary carbon atom, or a tertiary carbon atom.

[0052] From the viewpoint of suitably obtaining the effects of the present invention, the compound (C) is preferably at least one compound selected from the group consisting of alcohols (saturated aliphatic alcohols, unsaturated aliphatic alcohols, etc.), ether structure-containing hydroxy compounds, ester structure-containing hydroxy compounds, and ketone structure-containing hydroxy compounds. Specific preferred examples of the alcohol include monohydric saturated aliphatic alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, isobutyl alcohol, sec-butyl alcohol, tert-butyl alcohol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, 3-methyl-1-butanol, 2-methyl-2-butanol, 3-methyl-2-butanol, and 2,2-dimethyl-1-propanol; dihydric saturated aliphatic alcohols such as ethylene glycol, propylene glycol, trimethylene glycol, tetramethylene glycol, and pentamethylene glycol; monohydric unsaturated aliphatic alcohols such as allyl alcohol, crotyl alcohol, and 3-buten-1-ol; and dihydric unsaturated aliphatic alcohols such as 2-butene-1,4-diol. Preferable specific examples of the ether structure-containing hydroxy compound include monovalent ether structure-containing compounds such as 2-methoxyethanol (also known as methyl cellosolve, ethylene glycol monomethyl ether), 2-ethoxyethanol (also known as cellosolve, ethylene glycol monoethyl ether), 2-propoxyethanol (also known as ethylene glycol monopropyl ether), 2-isopropoxyethanol (also known as ethylene glycol monoisopropyl ether), 1-methoxy-2-propanol (also known as propylene glycol monomethyl ether), 1-ethoxy-2-propanol (also known as propylene glycol monoethyl ether), and 2-(2-methoxyethoxy)ethanol (also known as diethylene glycol monomethyl ether: methyl carbitol); and divalent ether structure-containing hydroxy compounds such as diethylene glycol. Preferred specific examples of the ester structure-containing hydroxy compound include compounds such as ethylene glycol monoacetate (also known as 2-hydroxyethyl acetate), methyl lactate (also known as methyl lactate), ethyl lactate (also known as ethyl lactate), and methyl 2-hydroxyisobutyrate. Preferred specific examples of the ketone structure-containing hydroxy compound include 4-hydroxy-2-pentanone, 5-hydroxy-2-pentanone, acetol, and 3-hydroxy-3-methyl-2-butanone.

[0053] From the viewpoint of suitably obtaining the effects of the present invention, the alcohol is preferably at least one compound selected from methanol, ethanol, 1-propanol, 2-propanol, tert-butyl alcohol, 1-butanol, sec-butyl alcohol, propylene glycol monomethyl ether, and ethyl lactate.

[0054] The total content of the compound (C) is 0.1% by mass or more and less than 11% by mass, when the total components in the liquid crystal alignment agent are taken as 100% by mass. The total content of the compound (C) is more preferably 0.2% by mass or more, and even more preferably 0.3% by mass or more, when the total components in the liquid crystal alignment agent are taken as 100% by mass. The ratio of the total mass of the components other than the (C) component of the liquid crystal alignment agent to the total mass of the liquid crystal alignment agent is 99.9% by mass or less, more preferably 99.8% by mass or less, and even more preferably 99.7% by mass or less, when all the components in the liquid crystal alignment agent are taken as 100% by mass. Furthermore, the ratio of the total mass of the components other than the (C) component of the liquid crystal alignment agent to the total mass of the liquid crystal alignment agent is more than 88% by mass, when all the components in the liquid crystal alignment agent are taken as 100% by mass.

[0055] The liquid crystal alignment agent of the present invention contains an organic solvent (excluding the component (C)). Specific examples of the organic solvent include N,N-dimethylformamide, N,N-dimethylacetamide, N,N-dimethyllactamide, N,N-dimethylpropionamide, tetramethylurea, N,N-diethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethylsulfoxide, γ-butyrolactone, γ-valerolactone, 1,3-dimethyl-2-imidazolidinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, 3-methoxy-N ... Examples of the solvent include N-propanamide, 3-butoxy-N,N-dimethylpropanamide, N-(n-propyl)-2-pyrrolidone, N-isopropyl-2-pyrrolidone, N-(n-butyl)-2-pyrrolidone, N-(tert-butyl)-2-pyrrolidone, N-(n-pentyl)-2-pyrrolidone, N-methoxypropyl-2-pyrrolidone, N-ethoxyethyl-2-pyrrolidone, N-methoxybutyl-2-pyrrolidone, and N-cyclohexyl-2-pyrrolidone (collectively referred to as "good solvents"). Among these, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, and γ-butyrolactone are preferred. The content of the good solvent is preferably 20% by mass or more, and more preferably 30% by mass or more, when the total amount of all components in the liquid crystal alignment agent is taken as 100% by mass.

[0056] In addition, the organic solvent contained in the liquid crystal alignment agent is preferably a mixed solvent containing the above-mentioned solvent and a solvent (also called a poor solvent) that improves the coatability and surface smoothness of the coating film when applying the liquid crystal alignment agent. The content of the poor solvent is preferably 1% by mass or more, more preferably 5% by mass or more, and even more preferably 10% by mass or more, when the total components in the liquid crystal alignment agent are taken as 100% by mass. The total content of the good solvent and the poor solvent is preferably 99.9% by mass or less, more preferably 99.8% by mass or less, and even more preferably 99.7% by mass or less, when the total amount of all components in the liquid crystal alignment agent is 100% by mass. The type and content of the poor solvent are appropriately selected depending on the coating device, coating conditions, coating environment, etc. of the liquid crystal alignment agent. Specific examples of the poor solvent are listed below, but are not limited thereto.

[0057] Diisopropyl ether, diisobutyl ether, diisobutyl carbinol (2,6-dimethyl-4-heptanol), ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, 4-hydroxy-4-methyl-2-pentanone, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, 3-ethoxybutyl acetate, 1-methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, ethylene glycol diacetate, propylene carbonate, ethylene carbonate, ethylene glycol monobutyl ether, ethylene glycol monoisoamyl ether, ethylene glycol monohexyl ether, propylene glycol monobutyl ether, 1-(2-butoxyethoxy)-2-propanol, 2-(2-butoxyethoxy)-1-propanol, propylene glycol monomethyl ether Examples of the ethyl acetate include butyl acetate, propylene glycol diacetate, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monobutyl ether acetate, diethylene glycol monopropyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 2-(2-ethoxyethoxy)ethyl acetate, diethylene glycol diacetate, propylene glycol diacetate, n-butyl acetate, propylene glycol monoethyl ether acetate, cyclohexyl acetate, 4-methyl-2-pentyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, butyl 3-methoxypropionate, n-butyl lactate, isoamyl lactate, diethylene glycol monoethyl ether, and diisobutyl ketone (2,6-dimethyl-4-heptanone).

[0058] Among these, the poor solvent is preferably diisobutyl carbinol, propylene glycol monobutyl ether, propylene glycol diacetate, diethylene glycol diethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, or diisobutyl ketone.

[0059] Preferred combinations of good and poor solvents include N-methyl-2-pyrrolidone and ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone and ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone and propylene glycol monobutyl ether, N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether, N-ethyl-2-pyrrolidone and 4-hydroxy-4-methyl-2-pentanone, and N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether. diacetate, N,N-dimethyl lactamide and diisobutyl ketone, N-methyl-2-pyrrolidone and ethyl 3-ethoxypropionate, N-ethyl-2-pyrrolidone and ethyl 3-ethoxypropionate, N-ethyl-2-pyrrolidone and ethyl 3-ethoxypropionate, N-ethyl-2-pyrrolidone and ethyl 3-ethoxypropionate and propylene glycol monobutyl ether, N-methyl-2-pyrrolidone and ethyl 3-ethoxypropionate and diethylene glycol monopropyl ether, N-ethyl-2-pyrrolidone and ethyl 3-ethoxypropionate and diethylene glycol monopropyl ether, N-methyl-2-pyrrolidone and ethylene glycol monobutyl ether acetate, N-ethyl-2-pyrrolidone and dipropylene glycol dimethyl ether, N,N-dimethyl lactamide and ethylene glycol monobutyl ether, N,N-dimethyl lactamide and propylene glycol diacetate, N-ethyl-2-pyrrolidone and diethylene glycol diethyl ether, N-ethyl-2-pyrrolidone and diethylene glycol monoethyl ether and butyl cellosolve acetate, N-methyl-2-pyrrolidone and Diethylene glycol monomethyl ether and butyl cellosolve acetate, N,N-dimethyl lactamide and diethylene glycol diethyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone, 4-hydroxy-4-methyl-2-pentanone and diethylene glycol diethyl ether, N-ethyl-2-pyrrolidone, N-methyl-2-pyrrolidone and 4-hydroxy-4-methyl-2-pentanone, N-ethyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone and propylene glycol monobutyl ether,N-methyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone and diisobutyl ketone, N-methyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone and dipropylene glycol monomethyl ether, N-methyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone and propylene glycol monobutyl ether, N-methyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone and propylene glycol diacetate, N-ethyl-2-pyrrolidone and 4-hydroxy-4-methyl -2-pentanone and dipropylene glycol dimethyl ether, γ-butyrolactone and 4-hydroxy-4-methyl-2-pentanone and diisobutyl ketone, γ-butyrolactone and 4-hydroxy-4-methyl-2-pentanone and propylene glycol diacetate, N-methyl-2-pyrrolidone and γ-butyrolactone and propylene glycol monobutyl ether and diisobutyl ketone, N-methyl-2-pyrrolidone and γ-butyrolactone and propylene glycol monobutyl ether and diisopropyl ether, N-methyl-2-pyrrolidone and γ-butyrolactone and 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, N-methyl-2-pyrrolidone, propylene glycol monobutyl ether, and dipropylene glycol dimethyl ether, N-ethyl-2-pyrrolidone, propylene glycol monobutyl ether, and dipropylene glycol monomethyl ether, N-ethyl-2-pyrrolidone, diethylene glycol diethyl ether, and dipropylene glycol monomethyl ether, N-ethyl-2-pyrrolidone, propylene glycol monobutyl ether, and propylene glycol diacetate, N-ethyl-2-pyrrolidone, propylene glycol monobutyl ether, and diisobutyl ketone, N-ethyl-2-pyrrolidone, γ-butyrolactone, and diisobutyl ketone, N-ethyl-2-pyrrolidone, N,N-dimethyl lactamide, and diisobutyl ketone, N-methyl-2-pyrrolidone, ethylene glycol monobutyl ether, and ethylene glycol monobutyl ether acetate,Examples of the mixture include γ-butyrolactone, ethylene glycol monobutyl ether acetate, and dipropylene glycol dimethyl ether, N-ethyl-2-pyrrolidone, ethylene glycol monobutyl ether acetate, and propylene glycol dimethyl ether, N-methyl-2-pyrrolidone, 4-methyl-2-pentyl acetate, and ethylene glycol monobutyl ether, and N-methyl-2-pyrrolidone, cyclohexanone, and propylene glycol monomethyl ether.

[0060] The solid content concentration in the liquid crystal alignment agent (the ratio of the total mass of the components other than the solvent of the liquid crystal alignment agent to the total mass of the liquid crystal alignment agent) is appropriately selected in consideration of viscosity, volatility, etc., and is preferably in the range of 1 to 10 mass%. From the viewpoint of forming a uniform and defect-free coating film, 1 mass% or more is preferable, and from the viewpoint of storage stability of the solution, 10 mass% or less is preferable. A particularly preferable solid content concentration is 2 to 8 mass%. The range of the solid content may be appropriately selected depending on the method used for applying the liquid crystal alignment agent to the substrate. For example, when spin-coating is performed, the solid content is particularly preferably 1.5 to 4.5 mass%. When using the printing method, the solid content is particularly preferably 3 to 9 mass%, thereby giving a solution viscosity of 12 to 50 mPa·s. When using the inkjet method, the solid content is particularly preferably 1 to 5 mass%, thereby giving a solution viscosity of 3 to 15 mPa·s. The temperature when preparing the liquid crystal alignment agent is preferably 10 to 50°C, more preferably 20 to 30°C. The concentration of the polymer component in the liquid crystal alignment agent can be appropriately changed depending on the thickness of the coating film to be formed. From the viewpoint of forming a uniform and defect-free coating film, the concentration of the polymer component in the liquid crystal alignment agent (total concentration of polymers) is preferably 1% by mass or more, and from the viewpoint of storage stability of the solution, it is preferably 10% by mass or less. The particularly preferred polymer concentration is 2 to 8% by mass. The content of the polymer component (P) in the liquid crystal alignment agent (the total amount of polymers constituting the polymer component (P)) is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, and even more preferably 50 parts by mass or more, relative to 100 parts by mass of the total of the polymer components contained in the liquid crystal alignment agent, from the viewpoint of preferably obtaining the effects of the present disclosure. When the liquid crystal alignment agent contains other polymers described later, the content of the polymer component (P) is preferably 99.9 parts by mass or less, more preferably 99 parts by mass or less, per 100 parts by mass of the total of the polymers contained in the liquid crystal alignment agent.

[0061] The liquid crystal alignment agent of the present invention may contain other components as necessary. Examples of the components include other polymers than the polyimide precursors (A) and (B); at least one compound selected from the group consisting of crosslinkable compounds having at least one substituent selected from epoxy groups, isocyanate groups, oxetanyl groups, cyclocarbonate groups, blocked isocyanate groups, hydroxyl groups, and alkoxy groups (excluding the above hydroxyl compounds (c)); and crosslinkable compounds having polymerizable unsaturated groups; functional silane compounds; metal chelate compounds; curing accelerators; surfactants; antioxidants; sensitizers; preservatives; compounds for adjusting the dielectric constant and electrical resistance of the liquid crystal alignment film; and compounds for promoting imidization.

[0062] Specific examples of other polymers include polymers selected from the group consisting of polysiloxanes, polyesters, polyamides, polyureas, polyurethanes, polyorganosiloxanes, cellulose derivatives, polyacetals, polystyrene derivatives, poly(styrene-maleic anhydride) copolymers, poly(isobutylene-maleic anhydride) copolymers, poly(vinyl ether-maleic anhydride) copolymers, poly(styrene-phenylmaleimide) derivatives, and poly(meth)acrylates.

[0063] Specific examples of poly(styrene-maleic anhydride) copolymers include SMA1000, 2000, 3000 (Cray Valley), GSM301 (Gifu Ceramics Manufacturing Co., Ltd.), etc., specific examples of poly(isobutylene-maleic anhydride) copolymers include ISOBAM-600 (Kuraray), and specific examples of poly(vinyl ether-maleic anhydride) copolymers include Gantrez AN-139 (methyl vinyl ether maleic anhydride resin, Ashland). The other polymers may be used alone or in combination of two or more. The content ratio of the other polymers is preferably 90 parts by mass or less, more preferably 80 parts by mass or less, relative to a total of 100 parts by mass of the polymers contained in the liquid crystal alignment agent. The content ratio of the other polymers is preferably 0.1 parts by mass or more, more preferably 1 part by mass or more, relative to a total of 100 parts by mass of the polymers contained in the liquid crystal alignment agent.

[0064] Specific preferred examples of the crosslinkable compound include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl ether, Diphenyl-2,4-hexanediol, bisphenol A type epoxy resins such as Epicoat 828 (manufactured by Mitsubishi Chemical Corporation), bisphenol F type epoxy resins such as Epicoat 807 (manufactured by Mitsubishi Chemical Corporation), hydrogenated bisphenol A type epoxy resins such as YX-8000 (manufactured by Mitsubishi Chemical Corporation), biphenyl skeleton-containing epoxy resins such as YX6954BH30 (manufactured by Mitsubishi Chemical Corporation), phenol novolac type epoxy resins such as EPPN-201 (manufactured by Nippon Kayaku Co., Ltd.), (o,m,p-) such as EOCN-102S (manufactured by Nippon Kayaku Co., Ltd.) Cresol novolac type epoxy resins, triglycidyl isocyanurates such as TEPIC (manufactured by Nissan Chemical Industries, Ltd.), alicyclic epoxy resins such as Celloxide 2021P (manufactured by Daicel Corporation), compounds containing tertiary nitrogen atoms such as N,N,N',N'-tetraglycidyl-m-xylylenediamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, or N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, and oxyesters such as tetrakis(glycidyloxymethyl)methane. Compounds having two or more silanyl groups; compounds having two or more oxetanyl groups described in paragraphs

[0170] to

[0175] of WO2011 / 132751; compounds having a blocked isocyanate group, such as Coronate AP Stable M, Coronate 2503, 2515, 2507, 2513, 2555, Millionate MS-50 (all manufactured by Tosoh Corporation), Takenate B-830, B-815N, B-820NSU, B-842N, B-846N, B-870N, B-874N, B-882N (all manufactured by Mitsui Chemicals, Inc.);Compounds having an oxazoline group such as 2,2'-bis(2-oxazoline), 2,2'-bis(4-methyl-2-oxazoline), 2,2'-bis(5-methyl-2-oxazoline), 1,2,4-tris(2-oxazolinyl)-benzene, and EPOCROS (manufactured by Nippon Shokubai Co., Ltd.); compounds having a cyclocarbonate group described in paragraphs

[0025] to

[0030] and

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

[0065] The compound for adjusting the dielectric constant or electrical resistance includes a monoamine having a nitrogen atom-containing aromatic heterocycle such as 3-picolylamine. The content of the monoamine having a nitrogen atom-containing aromatic heterocycle is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, based on 100 parts by mass of the polymer component contained in the liquid crystal alignment agent.

[0066] Specific preferred examples of the functional silane compound include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and 3-glycidoxypropylmethyldimethoxysilane. , 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, tris[3-(trimethoxysilyl)propyl]isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-isocyanatepropyltriethoxysilane, etc. The content of the functional silane compound is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, relative to 100 parts by mass of the polymer component contained in the liquid crystal alignment agent.

[0067] The compound for promoting the imidization is preferably a compound having a basic site (e.g., a primary amino group, an aliphatic heterocycle (e.g., a pyrrolidine skeleton), an aromatic heterocycle (e.g., an imidazole ring, an indole ring), or a guanidino group, etc.) (excluding the crosslinkable compound and the adhesion aid), or a compound that generates the basic site when baked. More preferably, it is a compound that generates the basic site when baked, and a preferred specific example is an amino acid in which a part or all of the basic site of the amino acid is protected. Examples of the protecting group for the basic site of the amino acid include a carbamate-based protecting group such as a Boc group. Specific examples of the amino acid include glycine, alanine, cysteine, methionine, asparagine, glutamine, valine, leucine, phenylalanine, tyrosine, tryptophan, proline, hydroxyproline, arginine, histidine, lysine, and ornithine. A more preferred specific example of the compound for promoting imidization is N-α-(9-fluorenylmethoxycarbonyl)-N-τ-(tert-butoxycarbonyl)-L-histidine. The content of the compound for promoting imidization contained in the liquid crystal aligning agent of the present invention is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, and even more preferably 5 to 20 parts by mass, relative to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent.

[0068] (Liquid crystal alignment film and liquid crystal display element) The liquid crystal display element according to the present invention comprises a liquid crystal alignment film formed using the liquid crystal aligning agent. The liquid crystal alignment film of the present invention can be produced, for example, by a method including the following steps (1) to (2) or a method including the following steps (1) to (3). The operating mode of the liquid crystal display element is not particularly limited, and can be applied to various operating modes such as TN mode, STN mode, vertical alignment mode (including VA-MVA mode, VA-PVA mode, etc.), in-plane switching mode (IPS mode, FFS mode), and optically compensated bend mode (OCB mode).

[0069] The liquid crystal display element of the present invention can be produced, for example, by a method including the following steps (1) to (4), a method including steps (1) to (2) and (4), a method including steps (1) to (3), (4-2) and (4-4), or a method including steps (1) to (3), (4-3) and (4-4). Moreover, one embodiment of the liquid crystal display element of the present invention is a liquid crystal display element having a liquid crystal alignment film formed by a method for producing a liquid crystal alignment film, the method including the following steps (1) to (2) or steps (1) to (3):

[0070] <Step (1): Step of applying liquid crystal alignment agent onto a substrate> Step (1) is a step of applying a liquid crystal alignment agent onto a substrate. A specific example of step (1) is as follows. A liquid crystal alignment agent is applied to one side of a substrate on which a patterned transparent conductive film is provided by an appropriate application method such as a roll coater method, a spin coat method, a printing method, or an inkjet method. The material of the substrate is not particularly limited as long as it is a highly transparent substrate, and plastics such as acrylic and polycarbonate can be used in addition to glass and silicon nitride. In addition, 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 be used for the electrode. In addition, when manufacturing an IPS or FFS liquid crystal display element, a substrate on which an electrode made of a transparent conductive film or a metal film patterned into a comb shape is provided and an opposing substrate on which no electrode is provided are used. An IPS substrate, which is a comb-tooth electrode substrate used in an IPS-type liquid crystal display element, has, for example, a base material, a plurality of linear electrodes formed on the base material and arranged in a comb-tooth shape, and a liquid crystal alignment film formed on the base material so as to cover the linear electrodes. An FFS substrate, which is a comb-tooth electrode substrate used in an FFS-type liquid crystal display element, has, for example, a base material, a surface electrode formed on the base material, an insulating film formed on the surface electrode, a plurality of linear electrodes formed on the insulating film and arranged in a comb-tooth shape, and a liquid crystal alignment film formed on the insulating film so as to cover the linear electrodes.

[0071] Examples of the 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, a spray method, etc. Among these, the application and film formation method by the inkjet method is preferably used.

[0072] <Step (2): Step of baking the applied liquid crystal alignment agent> In step (2), the liquid crystal alignment agent applied to the substrate is baked to form a film. A specific example of step (2) is as follows. After the liquid crystal alignment agent is applied to the substrate in step (1), the solvent can be evaporated or the polyimide precursor, typified by polyamic acid, can be thermally imidized by a heating means such as a hot plate, a heat circulation type oven, or an IR (infrared) type oven. The drying and baking process after the application of the liquid crystal alignment agent can be performed at any temperature and time, and may be performed multiple times. The temperature for baking the liquid crystal alignment agent can be, for example, 40 to 180°C. From the viewpoint of shortening the process, it may be performed at 40 to 150°C. The baking time is not particularly limited, but may be 1 to 10 minutes or 1 to 5 minutes. When thermally imidizing the polyimide precursor, typified by polyamic acid, a baking process at, for example, 150 to 300°C or 150 to 250°C may be added after the above process. The baking time is not particularly limited, but may be 5 to 40 minutes or 5 to 30 minutes. The thickness of the film after firing is preferably 5 to 300 nm, more preferably 10 to 200 nm, since if it is too thin, the reliability of the liquid crystal display element may decrease.

[0073] <Step (3): Step of subjecting the film obtained in step (2) to an alignment treatment> Step (3) is a step of subjecting the film obtained in step (2) to an alignment treatment, if necessary. That is, in a horizontal alignment type liquid crystal display element such as an IPS type or an FFS type, the coating film is subjected to an alignment ability imparting treatment. On the other hand, in a vertical alignment type liquid crystal display element such as a VA type or a PSA type, the formed coating film can be used as a liquid crystal alignment film as it is, but the coating film may be subjected to an alignment ability imparting treatment. Examples of the alignment treatment method for the liquid crystal alignment film include a rubbing alignment treatment method and a photo-alignment treatment method. Examples of the photo-alignment treatment method include a method in which the surface of the above-mentioned film-like material is irradiated with radiation, preferably polarized in a certain direction, and preferably heated to impart liquid crystal alignment (also called liquid crystal alignment ability). As the radiation, ultraviolet rays or visible light having a wavelength of 100 to 800 nm can be used. Among them, ultraviolet rays having a wavelength of 100 to 400 nm are preferable, and more preferably, ultraviolet rays having a wavelength of 200 to 400 nm are more preferable.

[0074] The radiation dose is 1 to 10,000 mJ / cm 2 is preferable, and among them, 100 to 5,000 mJ / cm 2 In the case of irradiating with radiation, the substrate having the film-like material may be irradiated while being heated at 50 to 250° C. in order to improve the liquid crystal alignment. The liquid crystal alignment film thus produced can stably align liquid crystal molecules in a certain direction. Examples of light sources for the irradiation light that can be used 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 irradiating light, the higher the extinction ratio of the 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.

[0075] Furthermore, the coating film irradiated with polarized radiation or the coating film subjected to rubbing alignment treatment by the above method may be subjected to a contact treatment using water or a solvent. The film subjected to the above alignment treatment may be subjected to a heat treatment without being subjected to a contact treatment. Furthermore, the film subjected to the above contact treatment may be further subjected to a heat treatment.

[0076] The solvent used in the contact treatment is not particularly limited as long as it dissolves the decomposition product 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, cyclohexyl acetate, etc. The solvent may be one type or a combination of two or more types.

[0077] The temperature for the heat treatment of the coating film irradiated with radiation or the film that has been subjected to the contact treatment is more preferably 50 to 300° C., more preferably 120 to 300° C., even more preferably 150 to 300° C., and most preferably 150 to 250° C. The heat treatment time is preferably 1 to 30 minutes.

[0078] <Step (4): Step of Producing a Liquid Crystal Cell> Two substrates on which the liquid crystal alignment film is formed are prepared as described above, and liquid crystal is placed between the two substrates arranged opposite each other. Specifically, the following two methods can be used. In the first method, first, two substrates are arranged facing each other with a gap (cell gap) between them so that the liquid crystal alignment films face each other, then the peripheries of the two substrates are bonded together using a sealant, and a liquid crystal composition is injected into the substrate surfaces and the cell gap defined by the sealant to contact the film surface, and then the injection hole is sealed.

[0079] The second method is a method called ODF (One Drop Fill) method. For example, a UV-curable sealant is applied to a predetermined location on one of the two substrates on which a liquid crystal alignment film is formed, and a liquid crystal composition is dropped at a predetermined number of locations on the liquid crystal alignment film surface. Thereafter, the other substrate is bonded 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 contacted with the film surface. Next, the entire surface of the substrate is irradiated with UV light to cure the sealant. In either method, it is preferable to further remove the flow alignment during liquid crystal filling by heating to a temperature at which the liquid crystal composition used has an isotropic phase and then slowly cooling to room temperature. When the coating films are subjected to a rubbing alignment treatment, the two substrates are disposed opposite each other so that the rubbing directions of the coating films are at a predetermined angle, for example, perpendicular or anti-parallel to each other. As the sealing agent, for example, an epoxy resin containing a hardener and aluminum oxide spheres as spacers can be used. The liquid crystal composition is not particularly limited, and may be a composition containing at least one liquid crystal compound (liquid crystal molecule), and may be a liquid crystal composition exhibiting a nematic phase (hereinafter also referred to as nematic liquid crystal), a liquid crystal exhibiting a smectic phase, or a liquid crystal composition exhibiting a cholesteric phase, among which nematic liquid crystal is preferred. In addition, various liquid crystal compositions having positive or negative dielectric anisotropy may be used. In the following, a liquid crystal composition having a positive dielectric anisotropy is also referred to as a positive type liquid crystal, and a liquid crystal composition having a negative dielectric anisotropy is also referred to as a negative type liquid crystal. The liquid crystal composition may contain a liquid crystal compound having a fluorine atom, a hydroxy group, an amino group, a fluorine atom-containing group (e.g., a trifluoromethyl group), a cyano group, an alkyl group, an alkoxy group, an alkenyl group, an isothiocyanate group, a heterocycle, a cycloalkane, a cycloalkene, a steroid skeleton, a benzene ring, or a naphthalene ring, and may contain a compound having two or more rigid moieties (mesogenic skeletons) that exhibit liquid crystallinity within the molecule (e.g., a bimesogenic compound in which two rigid biphenyl structures or terphenyl structures are linked by an alkyl group). The liquid crystal composition may further contain additives from the viewpoint of improving the liquid crystal alignment property. Such additives include photopolymerizable monomers such as compounds having a polymerizable group (e.g., (meth)acryloyl group), optically active compounds (e.g., S-811 manufactured by Merck Ltd.), antioxidants, ultraviolet absorbers, dyes, antifoaming agents, polymerization initiators, and polymerization inhibitors. Examples of the positive type liquid crystal include ZLI-2293, ZLI-4792, MLC-2003, MLC-2041, MLC-3019, and MLC-7081 manufactured by Merck. Examples of negative type liquid crystals include MLC-6608, MLC-6609, MLC-6610, MLC-7026, and MLC-7026-100 manufactured by Merck. Furthermore, an example of a liquid crystal containing a compound having a polymerizable group is MLC-3023 manufactured by Merck.

[0080] The liquid crystal aligning agent of the present invention is also preferably used for a liquid crystal display element (PSA type liquid crystal display element) which has a liquid crystal layer between a pair of substrates equipped with electrodes, and is manufactured through a process in which a liquid crystal composition containing a polymerizable compound which is polymerized by at least one of active energy rays and heat is placed between the pair of substrates, and the polymerizable compound is polymerized by at least one of irradiation with active energy rays and heating while applying a voltage between the electrodes. The liquid crystal alignment agent of the present invention is also preferably used for a liquid crystal display element (SC-PVA type liquid crystal display element) which has a liquid crystal layer between a pair of substrates equipped with electrodes, and is manufactured by disposing a liquid crystal alignment film between the pair of substrates, the liquid crystal alignment film including a polymerizable group that is polymerized by at least one of active energy rays and heat, and applying a voltage between the electrodes.

[0081] <Step (4-2): In the case of PSA type liquid crystal display element> The method is carried out in the same manner as in (4) above, except that a liquid crystal composition containing a polymerizable compound is injected or dropped. Examples of the polymerizable compound include polymerizable compounds having one or more polymerizable unsaturated groups in the molecule, such as an acrylate group or a methacrylate group.

[0082] <Step (4-3): In the case of an SC-PVA type liquid crystal display element> A method of manufacturing a liquid crystal display element may be adopted in which, after the same procedure as in (4) above, a step of irradiating ultraviolet light described later is carried out. According to this method, a liquid crystal display element having excellent response speed can be obtained with a small amount of light irradiation, as in the case of manufacturing the PSA type liquid crystal display element. The compound having a polymerizable group may be a compound having one or more of the above-mentioned polymerizable unsaturated groups in the molecule, and the content thereof is preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, relative to 100 parts by mass of the polymer component contained in the liquid crystal alignment agent. The polymerizable group may be contained in a polymer used in the liquid crystal alignment agent, and an example of such a polymer includes a polymer obtained by using a diamine component containing a diamine having the above-mentioned photopolymerizable group at its terminal in a reaction.

[0083] <Step (4-4): Step of irradiating ultraviolet rays> The liquid crystal cell is irradiated with light while a voltage is applied between the conductive films of the pair of substrates obtained in (4-2) or (4-3) above. The voltage applied here can be, for example, 5 to 50 V DC or AC. The light to be irradiated can be, for example, ultraviolet light and visible light containing light with a wavelength of 150 to 800 nm, but ultraviolet light containing light with a wavelength of 300 to 400 nm is preferred. The light source for the irradiation light can be, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, an excimer laser, or the like. The light irradiation dose is preferably 1,000 to 200,000 J / m 2 and more preferably 1,000 to 100,000 J / m 2 It is.

[0084] A liquid crystal display element can be obtained by attaching a polarizing plate to the outer surface of the liquid crystal cell as necessary. Examples of the polarizing plate to be attached to the outer surface of the liquid crystal cell include a polarizing plate in which a polarizing film called an "H film" made by absorbing iodine while stretching and aligning polyvinyl alcohol is sandwiched between cellulose acetate protective films, and a polarizing plate made of the H film itself. EXAMPLES

[0085] The present invention will be described in more detail below with reference to examples, but the present invention is not limited thereto. The abbreviations of the compounds used and the methods for measuring the respective properties are as follows.

[0086] (solvent) NMP: N-methyl-2-pyrrolidone BCS: Butyl cellosolve

[0087] ((C) component) EL: Ethyl lactate PGME: Propylene glycol monomethyl ether MeOH: Methanol EtOH: Ethanol IPA: 2-propanol

[0088] (Tetracarboxylic acid dianhydride) (ADA-1) to (ADA-3): Compounds represented by the following formulas (ADA-1) to (ADA-6), respectively. [ka]

[0089] (Diamine) (DA-1) to (DA-12): Compounds represented by the following formulas (DA-1) to (DA-12), respectively. [ka]

[0090] (Additives) AD-1: A compound represented by the following formula (AD-1): Additive A: N-α-(9-fluorenylmethoxycarbonyl)-N-τ-(tert-butoxycarbonyl)-L-histidine Additive B: 3-glycidoxypropylmethyldiethoxysilane [ka]

[0091] [Viscosity measurement] In the synthesis examples, the viscosity of the polyamic acid solution was measured using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.) with a sample amount of 1.1 mL, a cone rotor TE-1 (1°34', R24), and a temperature of 25°C.

[0092] (Synthesis of diamine)

[0093] The product in the following Monomer Synthesis Example 1 is 1 The product was identified by H-NMR analysis under the following analytical conditions: Equipment:BRUKER ADVANCE III-500MHz Measurement solvent: deuterated dimethyl sulfoxide (DMSO-d6) Reference material: Tetramethylsilane (TMS) (δ0.0 ppm for 1 H)

[0094] <Monomer synthesis example 1: Synthesis of DA-5> [ka]

[0095] 2-(4-nitrophenoxy)ethanol (30.0g, 0.164mol) was charged with THF (tetrahydrofuran, 120g) and pyridine (14.0g, 0.177mol), and stirred while cooling in an ice bath (0℃). Adipic acid dichloride (17.0g, 0.0929mol) dissolved in THF (60g) was added dropwise to the obtained solution, and after the dropwise addition, the mixture was stirred at room temperature (25℃) for 20 minutes, and then stirred at 45℃ for 18 hours. After the reaction was completed, the mixture was cooled to room temperature (25℃), and water (540g) was added to precipitate crystals. The crystals obtained by filtration were dried to obtain crude crystals (39g). THF (300g) was added to the crude crystals, and the mixture was heated and stirred at 70℃, and recrystallized by adding methanol (400g) while cooling in an ice bath (0℃). This was filtered, and the obtained crystals were dried to obtain DA-5-1 (yield: 34.0 g, 0.0713 mol, 88%). 1 H-NMR(500MHz) in DMSO-d6:δ(ppm)=8.19(d,J=9.5Hz,4H),7.16(d,J=9.5Hz,4H),4.37(q,4H),4.34(q,4H),2.33(t,4H),1.54-1.51(m,4H).

[0096] To the DA-5-1 (29.0 g, 0.0609 mol) obtained above, DMF (N,N-dimethylformamide, 290 g) was added and replaced with nitrogen, then carbon-supported palladium (5% Pd carbon powder (wet product) K type, manufactured by N.E. Chemcat) (2.32 g) was added and replaced with nitrogen again, a hydrogen Tedlar bag was attached, and the mixture was heated and stirred at 50 ° C for 18 hours. After the reaction was completed, the carbon-supported palladium was removed by passing through a membrane filter, and water (1000 g) was added to the filtrate and stirred to precipitate crystals. This was filtered to obtain crude crystals (24 g). THF (92 g) was added to the crude crystals, heated and stirred at 50 ° C, and slurry washed, then cooled in an ice bath (0 ° C), filtered, and the obtained crystals were dried to obtain crystals (22 g). The obtained crystals were added with DMF (66 g) and stirred at 50° C., then cooled in an ice bath (0° C.), and recrystallized by adding acetonitrile (88 g). The crystals were filtered and dried to obtain DA-5 (yield: 17.0 g, 0.0408 mol, 67%). 1 H-NMR(500MHz) in DMSO-d6: δ(ppm)=6.65(d,J=9.0Hz,4H),6.49(d,J=9.0Hz,4H),4.60(s,4H),4.26(t,4H),4.01(t,4H),2.33(t,4H),1.56-1.53(m,4H).

[0097] (Polymer synthesis) <Synthesis Example 1> In a 500mL four-neck flask equipped with a stirrer and nitrogen inlet tube, 2.16g (20.0mmol) of DA-1, 7.33g (30.0mmol) of DA-2, 9.61g (30.0mmol) of DA-3, and 7.97g (20.0mmol) of DA-7 were placed, and 311.3g of NMP was added. The mixture was stirred and dissolved while feeding nitrogen. While stirring this diamine solution, 20.85g (93.0mmol) of ADA-3 was added, and 40.1g of NMP was added so that the solid concentration became 12% by mass. The mixture was stirred at 40℃ for 24 hours to obtain a polyamic acid solution (PAA-1). The viscosity of this polyamic acid was 405mPa·s.

[0098] <Synthesis Example 2> In a 200mL four-neck flask equipped with a stirrer and nitrogen inlet tube, 6.38g (32.0mmol) of DA-6 and 1.22g (8.0mmol) of DA-8 were placed, and 110.1g of NMP was added. The mixture was stirred and dissolved while nitrogen was supplied. While stirring this diamine solution, 11.18g (38.0mmol) of ADA-1 was added, and 27.5g of NMP was added so that the solids concentration became 12% by mass. The mixture was stirred at 25℃ for 24 hours to obtain a polyamic acid solution (PAA-2). The viscosity of this polyamic acid was 398mPa·s.

[0099] <Synthesis Example 3> 3.44g (12.0mmol) of DA-4 and 1.25g (3.0mmol) of DA-5 were weighed out into a 100mL four-neck flask equipped with a stirrer and nitrogen inlet tube, 45.8g of NMP was added, and the mixture was dissolved by stirring while feeding nitrogen. While stirring this diamine solution under water cooling, 3.13g (14.0mmol) of ADA-3 was added, and then 11.5g of NMP was added. The mixture was stirred at 40℃ under a nitrogen atmosphere for 24 hours to obtain a polyamic acid solution (PAA-3). The viscosity of this polyamic acid was 320mPa·s.

[0100] <Synthesis Example 4> 3.19g (16.0mmol) of DA-6 and 0.61g (4.00mmol) of DA-8 were weighed out into a 100mL eggplant flask equipped with a stirrer and nitrogen inlet tube, 33.3g of NMP was added, and the mixture was dissolved by stirring while feeding nitrogen. While stirring this diamine solution under water cooling, 1.25g (5.0mmol) of ADA-2 was added, and then 3.7g of NMP was added, and the mixture was stirred at 50°C under a nitrogen atmosphere for 2 hours. Further, 32.0g of NMP was added, followed by 5.41g (18.4mmol) of ADA-1, and then 7.7g of NMP was added, and the mixture was stirred at 70°C for 12 hours under a nitrogen atmosphere to obtain a polyamic acid solution (PAA-4). The viscosity of this polyamic acid was 320mPa·s.

[0101] <Synthesis Example 5> DA-9 (13.7g, 59.3mmol) was placed in a 2000ml four-neck flask equipped with a stirrer and nitrogen inlet tube, and 153.3g of NMP was added. The mixture was stirred and dissolved while nitrogen was supplied. ADA-1 (16.6g, 56.5mmol) was added to this diamine solution while stirring, and then 17.0g of NMP was added. The mixture was stirred at 40°C for 24 hours under a nitrogen atmosphere to obtain a polyamic acid solution (PAA-5). The viscosity of this polyamic acid solution at 25°C was 504mPa s.

[0102] <Synthesis Example 6> 1.85g (9.23mmol) of DA-10 and 2.10g (13.82mmol) of DA-8 were weighed into a 100mL four-neck flask equipped with a stirrer and nitrogen inlet tube, 39.7g of NMP was added, and the mixture was stirred and dissolved while supplying nitrogen. 4.82g (22.08mmol) of ADA-4 was added while stirring this diamine solution, and then 10.0g of NMP was added. The mixture was stirred at room temperature for 24 hours to obtain a polyamic acid solution (PAA-6). The viscosity of this polyamic acid solution at 25℃ was 257mPa·s.

[0103] <Synthesis Example 7> 7.45g (26.0mmol) of DA-4 was placed in a 100ml four-neck flask equipped with a stirrer and nitrogen inlet tube, and 67.0g of NMP was added. The mixture was stirred and dissolved while nitrogen was supplied. 4.86g (24.8mmol) of ADA-4 was added to this diamine solution while stirring under water cooling, and 23.3g of NMP was added so that the solids concentration was 12% by mass. The mixture was stirred for 20 hours while heating at 50°C under a nitrogen atmosphere to obtain a polyamic acid solution (PAA-7). The viscosity of this polyamic acid solution at 25°C was 530mPa·s.

[0104] <Synthesis Example 8> 0.99g (5.00mmol) of DA-11 and 3.99g (20.0mmol) of DA-6 were placed in a 100ml four-neck flask equipped with a stirrer and a nitrogen inlet tube, and 57.2g of NMP was added. The mixture was stirred and dissolved while feeding nitrogen. 1.50g (5.00mmol) of ADA-6 and 1.07g of NMP were added while stirring the diamine solution under water cooling, and the mixture was stirred for 3 hours under a nitrogen atmosphere and water cooling. Then, 3.53g (18.0mmol) of ADA-5 was added, and 31.8g of NMP was added so that the solid content concentration was 10% by mass. The mixture was stirred again under a nitrogen atmosphere and water cooling for 3 hours to obtain a polyamic acid solution (PAA-8). The viscosity of this polyamic acid solution at 25°C was 165mPa·s.

[0105] <Synthesis Example 9> 7.45g (30.0mmol) of DA-12 was placed in a 100ml four-neck flask equipped with a stirrer and nitrogen inlet tube, and 92.3g of NMP was added. The mixture was stirred and dissolved while nitrogen was supplied. 6.22g (27.8mmol) of ADA-3 was added to this diamine solution while stirring under water cooling, and 7.94g of NMP was added so that the solids concentration was 12% by mass. The mixture was again stirred for 24 hours while heating at 40°C under a nitrogen atmosphere to obtain a polyamic acid solution (PAA-9). The viscosity of this polyamic acid solution at 25°C was 347mPa·s.

[0106] The specifications of the polyamic acids obtained in the above synthesis examples are shown in Table 1. In the table, the numbers in parentheses for the tetracarboxylic acid components indicate the amount (parts by mole) of each tetracarboxylic dianhydride used per 100 parts by mole of the total amount of the tetracarboxylic acid components used in the polymerization. The numbers in parentheses for the diamine components indicate the amount (parts by mole) of each diamine used per 100 parts by mole of the total amount of the diamine components used in the polymerization.

[0107] [Table 1]

[0108] (Preparation of Liquid Crystal Alignment Agent) <Example 1> In a 50 mL Erlenmeyer flask containing a stirrer, 8.67 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1, 8.67 g of the polyamic acid solution (PAA-2) obtained in Synthesis Example 2, 2.08 g of a 1.0 mass% solution of additive B in NMP, 1.04 g of a 10 mass% solution of AD-1 in NMP, 10.94 g of NMP, 0.40 g of EL, 8.00 g of BCS, and 0.21 g of additive A were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-1).

[0109] <Example 2> A liquid crystal aligning agent (AL-1) was prepared in the same manner as in Example 1 above, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-1-24h).

[0110] <Example 3> In a 50 mL Erlenmeyer flask containing a stirrer, 8.67 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1, 8.67 g of the polyamic acid solution (PAA-2) obtained in Synthesis Example 2, 2.08 g of a 1.0 mass% solution of additive B in NMP, 1.04 g of a 10 mass% solution of AD-1 in NMP, 9.34 g of NMP, 2.00 g of EL, 8.00 g of BCS, and 0.21 g of additive A were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-2).

[0111] <Example 4> A liquid crystal aligning agent (AL-2) was prepared in the same manner as in Example 3 above, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-2-24h).

[0112] <Example 5> In a 50 mL Erlenmeyer flask containing a stirrer, 8.67 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1, 8.67 g of the polyamic acid solution (PAA-2) obtained in Synthesis Example 2, 2.08 g of a 1.0 mass% solution of additive B in NMP, 1.04 g of a 10 mass% solution of AD-1 in NMP, 9.34 g of NMP, 2.00 g of PGME, 8.00 g of BCS, and 0.21 g of additive A were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-3).

[0113] <Example 6> A liquid crystal aligning agent (AL-3) was prepared in the same manner as in Example 5 above, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-3-24h).

[0114] <Example 7> In a 50 mL Erlenmeyer flask containing a stirrer, 8.67 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1, 8.67 g of the polyamic acid solution (PAA-2) obtained in Synthesis Example 2, 2.08 g of a 1.0 mass% solution of additive B in NMP, 1.04 g of a 10 mass% solution of AD-1 in NMP, 11.34 g of NMP, 8.00 g of BCS, and 0.21 g of additive A were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-4).

[0115] <Example 8> A liquid crystal aligning agent (AL-4) was prepared in the same manner as in Example 7 above, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-4-24h).

[0116] <Example 9> In a 50 mL Erlenmeyer flask containing a stirrer, 5.20 g of the polyamic acid solution (PAA-3) obtained in Synthesis Example 3, 12.13 g of the polyamic acid solution (PAA-4) obtained in Synthesis Example 4, 2.08 g of a 1.0 mass% solution of additive B in NMP, 1.04 g of a 10 mass% solution of AD-1 in NMP, 7.55 g of NMP, 4.00 g of MeOH, and 8.00 g of BCS were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-5).

[0117] <Example 10> A liquid crystal aligning agent (AL-5) was prepared in the same manner as in Example 9 above, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-5-24h).

[0118] <Example 11> In a 50 mL Erlenmeyer flask containing a stirrer, 5.20 g of the polyamic acid solution (PAA-3) obtained in Synthesis Example 3, 12.13 g of the polyamic acid solution (PAA-4) obtained in Synthesis Example 4, 2.08 g of a 1.0 mass% NMP solution of additive B, 1.04 g of a 10 mass% NMP solution of AD-1, 7.55 g of NMP, 4.00 g of EtOH, and 8.00 g of BCS were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-6).

[0119] <Example 12> A liquid crystal aligning agent (AL-6) was prepared in the same manner as in Example 11 above, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-6-24h).

[0120] <Example 13> In a 50 mL Erlenmeyer flask containing a stirrer, 5.20 g of the polyamic acid solution (PAA-3) obtained in Synthesis Example 3, 12.13 g of the polyamic acid solution (PAA-4) obtained in Synthesis Example 4, 2.08 g of a 1.0 mass% NMP solution of additive B, 1.04 g of a 10 mass% NMP solution of AD-1, 7.55 g of NMP, 4.00 g of IPA, and 8.00 g of BCS were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-7).

[0121] <Example 14> A liquid crystal aligning agent (AL-7) was prepared in the same manner as in Example 13 above, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-7-24h).

[0122] <Example 15> In a 50 mL Erlenmeyer flask containing a stirrer, 5.20 g of the polyamic acid solution (PAA-3) obtained in Synthesis Example 3, 12.13 g of the polyamic acid solution (PAA-4) obtained in Synthesis Example 4, 2.08 g of a 1.0 mass% solution of additive B in NMP, 1.04 g of a 10 mass% solution of AD-1 in NMP, 7.55 g of NMP, 4.00 g of EL, and 8.00 g of BCS were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-8).

[0123] <Example 16> A liquid crystal aligning agent (AL-8) was prepared in the same manner as in Example 15 above, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-8-24h).

[0124] <Example 17> In a 50 mL Erlenmeyer flask containing a stirrer, 5.20 g of the polyamic acid solution (PAA-3) obtained in Synthesis Example 3, 12.13 g of the polyamic acid solution (PAA-4) obtained in Synthesis Example 4, 2.08 g of a 1.0 mass% solution of additive B in NMP, 1.04 g of a 10 mass% solution of AD-1 in NMP, 11.55 g of NMP, and 8.00 g of BCS were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-9).

[0125] <Example 18> A liquid crystal aligning agent (AL-9) was prepared in the same manner as in Example 17 above, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-9-24h).

[0126] The first polymer, the second polymer, the type of component (C) and the ratio of component (C) of the liquid crystal aligning agents obtained in Examples 1 to 18 are as shown in Table 2 below. In the following examples, Examples 1 to 6 and Examples 9 to 16 are working examples of the present invention, and Examples 7 to 8 and Examples 17 to 18 are comparative examples. In the table, the numerical values ​​in parentheses for the component (C) indicate the content (parts by mass) of each compound relative to 100 parts by mass of the total amount of each liquid crystal alignment agent.

[0127] [Table 2]

[0128] [Fabrication of FFS-driven liquid crystal cells (photo-alignment treatment)] (Examples 19-26) A liquid crystal cell having the configuration of a liquid crystal display element of the FFS driving method was fabricated. First, a substrate with electrodes was prepared. The substrate was a glass substrate with a size of 30 mm x 50 mm and a thickness of 0.7 mm. An ITO electrode with a solid pattern was formed on the substrate as the first layer, which constituted the counter electrode. A SiN (silicon nitride) film formed by CVD was formed as the second layer on the first layer of the counter electrode. The second layer of SiN film had a thickness of 500 nm, which functioned as an interlayer insulating film. A comb-shaped pixel electrode formed by patterning an ITO film was arranged as the third layer on the second layer of SiN film, and two pixels, the first pixel and the second pixel, were formed. The size of each pixel was 10 mm in length and about 5 mm in width. At this time, the first layer of the counter electrode and the third layer of the pixel electrode were electrically insulated by the action of the second layer of SiN film.

[0129] The pixel electrode in the third layer had a comb-like shape in which multiple 3 μm-wide electrode elements, with the central portion bent at an internal angle of 160°, were arranged in parallel with each other at 6 μm intervals, and each pixel had a first region and a second region, separated by a line connecting the bent portions of the multiple electrode elements. Comparing the first and second regions of each pixel, the directions of the electrode elements of the pixel electrodes constituting them were different. That is, when the direction connecting the bent portions of the above-mentioned multiple electrode elements was taken as a reference, the electrode elements of the pixel electrodes in the first region of the pixel were formed to form an angle of 80° clockwise, and the electrode elements of the pixel electrodes in the second region of the pixel were formed to form an angle of 80° counterclockwise. That is, the first and second regions of each pixel were configured such that the directions of rotational movement (in-plane switching) of the liquid crystal molecules in the substrate plane induced by application of a voltage between the pixel electrode and the counter electrode were opposite to each other.

[0130] Next, the liquid crystal alignment agents (AL-1) to (AL-4) and (AL-1-24h) to (AL-4-24h) obtained in Preparation Examples 1 to 8 of the liquid crystal alignment agent were filtered with a 1.0 μm filter, and then applied by spin coating to the electrode-attached substrate and a glass substrate having a columnar spacer with a height of 4 μm and an ITO film formed on the back surface. After drying for 5 minutes on a hot plate at 80° C., the substrate was baked for 30 minutes in a hot air circulation oven at 230° C. to form a coating film with a thickness of 100 nm. Next, a photoalignment treatment was performed. Specifically, the coating surface was irradiated with linearly polarized ultraviolet light with a wavelength of 254 nm and an extinction ratio of 10:1 or more through a polarizing plate. The irradiation amount of the ultraviolet light was performed under the conditions shown in Table 3 below. In the following preparation examples, Examples 19 to 24 are examples of the present invention, and Examples 25 to 26 are comparative examples. Next, the substrate with the irradiated film was subjected to a heating step of heating on a hot plate at 230° C. for 30 minutes to obtain a substrate with a liquid crystal alignment film.

[0131] [Table 3]

[0132] Two substrates with the above liquid crystal alignment film were prepared, and a sealant (Mitsui Chemicals XN-1500T) was printed around the periphery, leaving the liquid crystal injection port, and the substrates were laminated together so that the liquid crystal alignment film surfaces faced each other and the alignment direction was 0°. After that, a heat treatment was performed at 120°C for 90 minutes to harden the sealant and prepare an empty cell. After negative liquid crystal MLC-7026-100 (Merck) was vacuum injected into this empty cell at room temperature, the injection port was sealed to prepare an anti-parallel aligned liquid crystal cell. The obtained liquid crystal cell with FFS driving mode was heated at 120°C for 1 hour, left overnight at 23°C, and then used for the following evaluations.

[0133] [Fabrication of FFS-driven liquid crystal cells (rubbing alignment treatment)] (Examples 27-36) A substrate with electrodes similar to the above and a glass substrate with columnar spacers were prepared. A coating film with a thickness of 100 nm was formed in the same manner as above, except that the liquid crystal alignment agents (AL-5) to (AL-9) and (AL-5-24h) to (AL-9-24h) obtained in Preparation Examples 9 to 18 of the liquid crystal alignment agent were used. Next, the above-mentioned photo-alignment treatment was changed to the rubbing alignment treatment described below, and an alignment treatment was performed. Specifically, the substrate on which the coating film was formed was rubbed with a rayon cloth (roller diameter: 140 mm, roller rotation speed: 1000 rpm, moving speed: 30 mm / sec, indentation length: 0.3 mm). Thereafter, the substrate was cleaned by irradiating ultrasonic waves in pure water for 1 minute, and water droplets were removed by air blowing, and then dried at 80°C for 10 minutes to obtain a substrate with a liquid crystal alignment film. Two substrates with the liquid crystal alignment film thus obtained were prepared, and liquid crystal cells of the FFS driving system were fabricated in the same manner as above, and used for the following evaluations. The fabrication examples of the liquid crystal cells, and the liquid crystal alignment agents and alignment treatment methods used in the fabrication of the liquid crystal cells are shown in Table 4. In the following fabrication examples, Examples 27 to 34 are examples of the present invention, and Examples 35 to 36 are comparative examples.

[0134] [Table 4]

[0135] [Evaluation of image lag due to long-term AC driving (evaluation of image lag due to orientation)] Using the liquid crystal cell with the FFS driving method prepared above, an AC voltage of ±5 V at a frequency of 60 Hz was applied for 120 hours in a constant temperature environment of 60° C. After that, the pixel electrode and the counter electrode of the liquid crystal cell were shorted, and the cell was left at room temperature for one day. After leaving it, the liquid crystal cell was placed between two polarizing plates arranged so that the polarization axes were perpendicular to each other, and the backlight was turned on with no voltage applied, and the arrangement angle of the liquid crystal cell was adjusted so that the brightness of the transmitted light was minimized. Then, the rotation angle when the liquid crystal cell was rotated from the angle at which the second region of the first pixel was the darkest to the angle at which the first region was the darkest was calculated as angle Δ1. Similarly, for the second pixel, the second region was compared with the first region, and a similar angle Δ2 was calculated. Then, the average value of the angle Δ1 obtained for the first pixel and the angle Δ2 obtained for the second pixel was calculated as the angle Δ of the liquid crystal cell, and the results are shown in Table 5 below. Furthermore, the difference in angle Δ between the case where the liquid crystal cell was left standing at 25° C. for 24 hours and the case where the liquid crystal cell was not left standing at 25° C. (hereinafter, also referred to as change value (X)) is also shown in Table 5 below. The change value (X) was calculated using the following formula. Change value (X) = AB A: Angle Δ of a liquid crystal cell prepared using a liquid crystal alignment agent left at 25°C for 24 hours B: Angle Δ of a liquid crystal cell prepared using a liquid crystal alignment agent that has not been left at 25°C for 24 hours When the change value (X) is small or a negative value, it means that the deterioration of the liquid crystal alignment caused by the amide exchange is suppressed, or the liquid crystal alignment is improved.

[0136] [Table 5]

[0137] It was confirmed that the change value (X) of Examples 19 to 24 and Examples 27 to 34, which are the embodiments of the present invention, is smaller or has a negative value compared to Examples 25 to 26 and Examples 35 to 36, which are the comparative examples. In other words, it was confirmed that by using the liquid crystal aligning agent of the present invention, the deterioration of liquid crystal alignment caused by the amide exchange reaction can be suppressed, or the liquid crystal alignment can be maintained or improved. <Example 37> In a 50 mL Erlenmeyer flask containing a stirrer, 8.67 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1, 6.97 g of the polyamic acid solution (PAA-5) obtained in Synthesis Example 5, 2.08 g of a 1.0 mass% solution of additive B in NMP, 1.04 g of a 10 mass% solution of AD-1 in NMP, 11.28 g of NMP, 2.00 g of PGME, 8.00 g of BCS, and 0.21 g of additive A were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-10).

[0138] <Example 38> A liquid crystal aligning agent (AL-10) was prepared in the same manner as in Example 37, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-10-24h).

[0139] <Example 39> In a 50 mL Erlenmeyer flask containing a stirrer, 8.67 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1, 6.97 g of the polyamic acid solution (PAA-6) obtained in Synthesis Example 6, 2.08 g of a 1.0 mass% solution of additive B in NMP, 1.04 g of a 10 mass% solution of AD-1 in NMP, 11.28 g of NMP, 2.00 g of PGME, 8.00 g of BCS, and 0.21 g of additive A were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-11).

[0140] <Example 40> A liquid crystal aligning agent (AL-11) was prepared in the same manner as in Example 39, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-11-24h).

[0141] <Example 41> In a 50 mL Erlenmeyer flask containing a stirrer, 6.93 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1, 12.48 g of the polyamic acid solution (PAA-8) obtained in Synthesis Example 8, 2.08 g of a 1.0 mass% solution of additive B in NMP, 1.04 g of a 10 mass% solution of AD-1 in NMP, 7.47 g of NMP, 2.00 g of PGME, 8.00 g of BCS, and 0.21 g of additive A were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-12).

[0142] <Example 42> A liquid crystal aligning agent (AL-12) was prepared in the same manner as in Example 41 above, and then the obtained liquid crystal aligning agent was left standing at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-12-24h).

[0143] <Example 43> In a 50 mL Erlenmeyer flask containing a stirrer, 5.20 g of the polyamic acid solution (PAA-9) obtained in Synthesis Example 9, 14.56 g of the polyamic acid solution (PAA-2) obtained in Synthesis Example 2, 2.08 g of a 1.0 mass% solution of additive B in NMP, 1.04 g of a 10 mass% solution of AD-1 in NMP, 7.20 g of NMP, 2.00 g of PGME, 8.00 g of BCS, and 0.21 g of additive A were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-13).

[0144] <Example 44> A liquid crystal aligning agent (AL-13) was prepared in the same manner as in Example 43, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-13-24h).

[0145] <Example 45> In a 50 mL Erlenmeyer flask containing a stirrer, 8.67 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1, 6.97 g of the polyamic acid solution (PAA-5) obtained in Synthesis Example 5, 2.08 g of a 1.0 mass% solution of Additive B in NMP, 1.04 g of a 10 mass% solution of AD-1 in NMP, 13.28 g of NMP, 8.00 g of BCS, and 0.21 g of Additive A were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-14).

[0146] <Example 46> A liquid crystal aligning agent (AL-14) was prepared in the same manner as in Example 45 above, and then the obtained liquid crystal aligning agent was left standing at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-14-24h).

[0147] <Example 47> In a 50 mL Erlenmeyer flask containing a stirrer, 8.67 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1, 6.97 g of the polyamic acid solution (PAA-6) obtained in Synthesis Example 6, 2.08 g of a 1.0 mass% solution of Additive B in NMP, 1.04 g of a 10 mass% solution of AD-1 in NMP, 13.28 g of NMP, 8.00 g of BCS, and 0.21 g of Additive A were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-15).

[0148] <Example 48> A liquid crystal aligning agent (AL-15) was prepared in the same manner as in Example 47, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-15-24h).

[0149] <Example 49> In a 50 mL Erlenmeyer flask containing a stirrer, 6.93 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1, 12.48 g of the polyamic acid solution (PAA-8) obtained in Synthesis Example 8, 2.08 g of a 1.0 mass% solution of Additive B in NMP, 1.04 g of a 10 mass% solution of AD-1 in NMP, 9.47 g of NMP, 8.00 g of BCS, and 0.21 g of Additive A were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-16).

[0150] <Example 50> A liquid crystal aligning agent (AL-16) was prepared in the same manner as in Example 47, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-16-24h).

[0151] <Example 51> In a 50 mL Erlenmeyer flask containing a stirrer, 5.20 g of the polyamic acid solution (PAA-9) obtained in Synthesis Example 9, 14.56 g of the polyamic acid solution (PAA-2) obtained in Synthesis Example 2, 2.08 g of a 1.0 mass% solution of Additive B in NMP, 1.04 g of a 10 mass% solution of AD-1 in NMP, 9.20 g of NMP, 8.00 g of BCS, and 0.21 g of Additive A were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-17).

[0152] <Example 52> A liquid crystal aligning agent (AL-17) was prepared in the same manner as in Example 51 above, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-17-24h).

[0153] <Example 53> In a 50 mL Erlenmeyer flask containing a stirrer, 5.20 g of the polyamic acid solution (PAA-7) obtained in Synthesis Example 7, 12.13 g of the polyamic acid solution (PAA-4) obtained in Synthesis Example 4, 2.08 g of a 1.0 mass% solution of additive B in NMP, 1.04 g of a 10 mass% solution of AD-1 in NMP, 9.55 g of NMP, 2.00 g of EL, and 8.00 g of BCS were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-18).

[0154] <Example 54> A liquid crystal aligning agent (AL-18) was prepared in the same manner as in Example 53, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-18-24h).

[0155] <Example 55> In a 50 mL Erlenmeyer flask containing a stirrer, 2.00 g of the polyamic acid solution (PAA-7) obtained in Synthesis Example 7, 9.60 g of the polyamic acid solution (PAA-8) obtained in Synthesis Example 8, 1.20 g of a 1 mass % NMP solution of additive B, 2.20 g of NMP, 1.00 g of EL, and 4.00 g of BCS were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-19).

[0156] <Example 56> A liquid crystal aligning agent (AL-19) was prepared in the same manner as in Example 55 above, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-19-24h).

[0157] <Example 57> In a 50 mL Erlenmeyer flask containing a stirrer, 5.20 g of the polyamic acid solution (PAA-7) obtained in Synthesis Example 7, 12.13 g of the polyamic acid solution (PAA-4) obtained in Synthesis Example 4, 2.08 g of a 1.0 mass% solution of Additive B in NMP, 1.04 g of a 10 mass% solution of AD-1 in NMP, 11.55 g of NMP, and 8.00 g of BCS were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-20).

[0158] <Example 58> A liquid crystal aligning agent (AL-20) was prepared in the same manner as in Example 57, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-20-24h).

[0159] <Example 59> In a 50 mL Erlenmeyer flask containing a stirrer, 2.00 g of the polyamic acid solution (PAA-7) obtained in Synthesis Example 7, 9.60 g of the polyamic acid solution (PAA-8) obtained in Synthesis Example 8, 1.20 g of a 1 mass % NMP solution of additive B, 3.20 g of NMP, and 4.00 g of BCS were added, and the mixture was stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (AL-21).

[0160] <Example 60> A liquid crystal aligning agent (AL-21) was prepared in the same manner as in Example 59, and then the obtained liquid crystal aligning agent was left to stand at 25° C. for 24 hours to obtain a liquid crystal aligning agent (AL-21-24h).

[0161] The first polymer, the second polymer, the type of component (C) and the ratio of component (C) of the liquid crystal aligning agents obtained in Examples 37 to 60 are shown in Table 6 below. In the following examples, Examples 37 to 44 and Examples 53 to 56 are working examples of the present invention, and Examples 45 to 52 and Examples 57 to 60 are comparative examples. In the table, the numerical values ​​in parentheses for the component (C) indicate the content (parts by mass) of each compound relative to 100 parts by mass of the total amount of each liquid crystal alignment agent.

[0162] [Table 6]

[0163] [Fabrication of FFS-driven liquid crystal cells (photo-alignment treatment)] (Examples 61-76) Using the liquid crystal alignment agents (AL-10) to (AL-17) and (AL-10-24h) to (AL-17-24h) prepared in the above Examples 37 to 52, and except that the amount of ultraviolet light irradiation was set to the conditions shown in the following Table 7, liquid crystal cells of the FFS driving mode were produced using the same method as the method described in the above Examples 19 to 26. In the following production examples, Examples 61 to 68 are examples of the present invention, and Examples 69 to 76 are comparative examples.

[0164] [Table 7]

[0165] [Fabrication of FFS-driven liquid crystal cells (rubbing alignment treatment)] (Examples 77-84) A liquid crystal cell of the FFS driving mode was produced using the same method as that described in the above Examples 27 to 36, except that the liquid crystal alignment agents (AL-18) to (AL-21) and (AL-18-24h) to (AL-21-24h) prepared in the above Examples 53 to 60 were used. The liquid crystal alignment agents and alignment treatment methods used in the production of the liquid crystal cells are shown in Table 8. In the following production examples, Examples 77 to 80 are examples of the present invention, and Examples 81 to 84 are comparative examples.

[0166] [Table 8]

[0167] [Evaluation of image lag due to long-term AC driving (evaluation of image lag due to orientation)] Using the liquid crystal cells prepared in the above Examples 61 to 84, afterimage evaluation was performed by long-term AC driving in the same manner as described above. The results are shown in Table 9.

[0168] [Table 9]

[0169] It was confirmed that the change value (X) of Examples 61 to 68 and Examples 77 to 80, which are the embodiments of the present invention, is smaller than that of Comparative Examples 69 to 76 and Examples 81 to 84. In other words, it was confirmed that by using the liquid crystal aligning agent of the present invention, the deterioration of liquid crystal alignment caused by the amide exchange reaction can be suppressed, or the liquid crystal alignment can be maintained or improved.

Claims

1. A liquid crystal aligning agent containing a polymer component (P) containing two or more types of polymers and a component (C), The polymer component (P) satisfies at least one of the following conditions (i) to (iii): The liquid crystal aligning agent, wherein the content of the component (C) is 0.1% by mass or more and less than 11% by mass, when all components in the liquid crystal aligning agent are taken as 100% by mass. (i) A polymer component (P1) having one or more structural units and containing two or more types of polyimide precursors (A) having a structural unit (a1) represented by the following formula (A1): (ii) A polymer component (P2) which is a polymer different from the polyimide precursor (A) and has one or more structural units and contains two or more types of polyimide precursors (B) having a structural unit (b1) represented by the following formula (B1): (iii) A polymer component (P3) containing the polyimide precursor (A) and the polyimide precursor (B). 【Chemistry 1】 (In formula (A1), X ａ１ represents a tetravalent organic group selected from the group consisting of the following formulae (Xa1-1) to (Xa1-8), and Y ａ１ represents a divalent organic group. 【Chemistry 2】 (In formulas (Xa1-1) to (Xa1-3), R １ From R １５ each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, or a phenyl group, and may be the same or different. * represents a bond.) 【Transformation 3】 (In formula (B1), X ｂ１ represents a tetravalent organic group having an aromatic group having 6 to 30 carbon atoms; X ｂ１ At least one of the carbonyl carbons bonded to X ｂ１ It bonds to the aromatic group of Y. ｂ１ represents a divalent organic group. Component (C): A compound (C) having 1 to 5 carbon atoms and 1 or 2 hydroxy groups.

2. The (C) component is at least one compound selected from methanol, ethanol, 1-propanol, 2-propanol, tert-butyl alcohol, 1-butanol, sec-butyl alcohol, propylene glycol monomethyl ether, and ethyl lactate, according to claim 1, the liquid crystal aligning agent.

3. In the formula (A1), X ａ１ The liquid crystal aligning agent according to claim 1, wherein is a tetravalent organic group represented by the above formula (Xa1-1).

4. In the formula (A1), X ａ１ The liquid crystal aligning agent according to claim 1, wherein is a tetravalent organic group selected from the group consisting of the following formulae (Xa1-1-1) to (Xa1-1-5): 【Chemistry 4】 (* represents a bond.)

5. In the formula (A1), Y ａ１ The liquid crystal aligning agent according to claim 1, wherein is a divalent organic group selected from the group consisting of the following formulas (3) to (4): 【Transformation 5】 (In formulas (3) and (4), R ３ , R ４ , and R ４’ each independently represents a halogen atom, a hydroxy group, an optionally protected amino group, a thiol group, a nitro group, a phosphate group, or a monovalent organic group having 1 to 20 carbon atoms. A ４ represents an ester bond, an amide bond, a thioester bond, or a divalent organic group having 2 to 20 carbon atoms, provided that 1,4-phenylene group, 1 to 4 of the hydrogen atoms on the phenylene group are R ４ , and R ４’ and divalent organic groups in which such divalent organic groups are linked to each other. a3, a4, and a4' each independently represents an integer of 0 to 4. a is an integer of 1 to 4. b and c are each independently an integer of 1 to 2. R ３ , R ４ , R ４’ If there are multiple R ３ , R ４ , and R ４’ The structures of may be the same or different. When a plurality of a3, a4, and a4' are present, they may be the same or different. * represents a bond.

6. In the formula (B1), X ｂ１ is expressed by the following formula (X ｂ１ -1) to (X ｂ１ The liquid crystal aligning agent according to claim 1, wherein the tetravalent organic group is selected from the group consisting of aryl, aryl- ... 【Transformation 6】 (* represents a bond.)

7. In the formula (B1), X ｂ１ is represented by the formula (X ｂ１ -1) to (X ｂ１ 2. The liquid crystal aligning agent according to claim 1, wherein the tetravalent organic group is selected from the group consisting of aryl, aryl- ...

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

9. A method for producing a liquid crystal alignment film, comprising the following steps (1) to (3): Step (1): A step of applying the liquid crystal aligning agent according to any one of claims 1 to 7 onto a substrate. Step (2): A step of baking the applied liquid crystal alignment agent Step (3): A step of subjecting the film obtained in step (2) to an alignment treatment.

10. The method for producing a liquid crystal alignment film according to claim 9 , wherein the alignment treatment is a photo-alignment treatment.

11. The method for producing a liquid crystal alignment film according to claim 10, further comprising the following baking step after the step (3): Firing step: A step of firing at 150°C to 300°C.

12. A liquid crystal alignment film formed by the method for producing a liquid crystal alignment film according to claim 9 .

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

14. A liquid crystal display device comprising the liquid crystal alignment film according to claim 12.

15. A method for manufacturing a liquid crystal display element, comprising forming the liquid crystal alignment film according to claim 8.

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