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

Abstract

The invention provides a liquid crystal aligning agent, a liquid crystal alignment film and a liquid crystal display element, wherein the liquid crystal aligning agent reduces deviation of torsion angles of liquid crystals, suppresses flicker and has high transmittance. The liquid crystal aligning agent contains: a polymer (A): a polyamic acid (A) having a structural unit derived from a tetracarboxylic acid derivative including a structural unit represented by formula (1Ta) and a structural unit derived from a diamine including a structural unit represented by formula (1Da), wherein at least a part of the terminal of the polyamic acid (A) contains a non-amino group as a functional group represented by formula (E); polymer (B): a polyamic acid (B) having a structural unit derived from a tetracarboxylic acid derivative including a structural unit represented by formula (1Tb) and a structural unit derived from a diamine. The present invention is characterized by comprising, as constituent units derived from a diamine, a constituent unit represented by formula (1Db1), a constituent unit represented by formula (1Db2), and a constituent unit represented by-N (Z)-YU-N (Z)-(YU represents a divalent organic group having a urea bond). # imgabs0 #

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 Art

[0002] Conventionally, liquid crystal display devices have been widely used as display units for personal computers, smartphones, mobile phones, television receivers, and the like. A liquid crystal display device typically includes: a liquid crystal layer sandwiched between a device substrate and a color filter substrate; pixel electrodes and a common electrode for applying an electric field to the liquid crystal layer; an alignment film for controlling the alignment of liquid crystal molecules in the liquid crystal layer; a thin film transistor (TFT: Thin Film Transistor) for switching an electric signal supplied to the pixel electrode; and the like. As driving methods for liquid crystal molecules, longitudinal electric field methods such as TN (Twisted Nematic) method and VA (Vertical Alignment) method are known; and lateral electric field methods such as IPS (In - Plane Switching) method and FFS (Fringe Field Switching) method are known.

[0003] Currently, the most widely used liquid crystal alignment film in the industry is produced by performing an alignment treatment on the surface of a film formed on an electrode substrate and made of a polymer represented by polyamic acid and / or polyimide obtained by imidizing the same. In recent years, with the high performance, high definition, and large size of liquid crystal display elements, a photo - alignment method for imparting liquid crystal alignment ability by irradiating polarized radiation has been studied. Regarding the photo - alignment method, methods using a photo - isomerization reaction, a photo - crosslinking reaction, a photo - decomposition reaction, etc. have been proposed (for example, refer to Non - Patent Document 1 and Patent Document 1).

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Patent Laid - Open No. 9 - 297313

[0007] Non - Patent Documents

[0008] Non - Patent Document 1: "Liquid Crystal Photo - Alignment Film", Kido Waki, Journal of Functional Materials, November 1997, Vol. 17, No. 11, pp. 113 - 122 Summary of the Invention

[0009] Problems to be Solved by the Invention

[0010] In recent years, large-sized and high-precision liquid crystal display elements have become the mainstream. In addition, the popularization of small-sized display terminals such as smartphones, tablet PCs, and car navigation systems has further increased the demand for higher quality of liquid crystal display elements compared to the past. Especially when the liquid crystal display element is enlarged, it is easy to generate deviations (non-uniformities) in the twist angle of the liquid crystal within the liquid crystal alignment film surface, and a liquid crystal aligning agent for a liquid crystal alignment film that can reduce the deviation of the twist angle of the liquid crystal is desired.

[0011] In addition, in recent high-brightness liquid crystal display elements, the brightness of the backlight becomes higher, and charges are accumulated when the backlight irradiates the liquid crystal cell immediately after driving, so problems such as flicker (scintillation) occur during driving.

[0012] Furthermore, from the viewpoint of reducing the power consumption of liquid crystal display elements, a higher transmittance is required for the liquid crystal alignment film than in the past.

[0013] Based on the above, the object of the present invention is to provide a liquid crystal aligning agent for a liquid crystal alignment film that reduces the deviation of the twist angle of the liquid crystal, suppresses the occurrence of flicker, and has a high transmittance, a liquid crystal alignment film obtained from the liquid crystal aligning agent, and a liquid crystal display element.

[0014] Solutions for Solving the Problems

[0015] The inventors of the present invention conducted in-depth research to solve the above problems and found the following facts, thereby completing the present invention: A liquid crystal aligning agent containing a first polyamic acid having a specific non-amino terminal structure and having a structural unit derived from a specific tetracarboxylic acid derivative and a structural unit derived from a diamine, and a second polyamic acid having a structural unit derived from a specific tetracarboxylic acid derivative and a structural unit derived from a specific diamine is extremely effective for achieving the above object.

[0016] The present invention includes the following solutions.

[0017] A liquid crystal aligning agent, characterized by containing the following polymer (A) and polymer (B).

[0018] Polymer (A): A polyamic acid (A) having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine.

[0019] As the structural unit derived from the tetracarboxylic acid derivative, it includes the structural unit (a-1Ta) represented by the following formula (1T a )).

[0020] As the structural unit derived from the diamine, it includes the structural unit (a-1Da) represented by the following formula (1D a )).

[0021] At least a part of the ends of the above-mentioned polyamic acid (A) contains a non-amino group, which is a functional group represented by the following structural formula (E).

[0022] Polymer (B): A polyamic acid (B) having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine.

[0023] As the structural unit derived from a tetracarboxylic acid derivative, it contains the structural unit (b-1Tb) represented by the following formula (1T b ).

[0024] As the structural unit derived from a diamine, it contains the structural unit (b-1Db1) represented by the following formula (1D b1 ), the structural unit (b-1Db2) represented by the following formula (1D b2 ), and the structural unit (b-1Db3) represented by "-N(Z)-Y U -N(Z)-", where Y U represents a divalent organic group having a urea bond, and Z has the same definition as Z in the following formula (1D a ).

[0025]

[0026] (In the formula, X a represents a tetravalent organic group represented by the following formula (x-1), and in the formula (1D a ), Y a represents a divalent organic group derived from a diamine, and Z each independently represents a hydrogen atom or a monovalent organic group.)

[0027]

[0028] (In the formula (x-1), R1 to R4 each independently represent 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, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 6 carbon atoms, an alkyloxycarbonyl group having 2 to 6 carbon atoms, or a phenyl group, and at least one of R1 to R4 represents a group other than a hydrogen atom in the above definition, and * represents a bonding bond.)

[0029]

[0030] (In the formula (E), Q is a monovalent organic group selected from the following groups (e1) to (e2), and * represents a bonding bond.)

[0031] (e1): An acyclic hydrocarbon group having 1 to 6 carbon atoms.

[0032] (e2): A monovalent organic group having 1 to 2 carboxyl groups and 2 to 30 carbon atoms (wherein the monovalent organic group does not contain an acid anhydride group).

[0033]

[0034] (In the formula, X b represents a tetravalent organic group derived from an aromatic tetracarboxylic dianhydride or a tetravalent organic group having an alicyclic structure with a five-membered ring or more (T 5a ).)

[0035]

[0036] (In formulas (1D b1 ) to (1D b2 ), Z has the same definition as Z in the above formula (1D a ). Any hydrogen atom on the benzene ring in formulas (1D b1 ) to (1D b2 ) is optionally substituted with a monovalent group.)

[0037] Advantages of the Invention

[0038] According to the present invention, there can be provided a liquid crystal aligning agent for a liquid crystal aligning film that reduces the deviation of the twist angle of a liquid crystal, suppresses the occurrence of flicker, and has a high transmittance, a liquid crystal aligning film obtained from the liquid crystal aligning agent, and a liquid crystal display element. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 FIG. is a schematic cross-sectional view showing an example of an in-plane switching (IPS) mode lateral electric field liquid crystal display element including a liquid crystal aligning film obtained from the liquid crystal aligning agent of the present invention.

[0040] <~ Figure 2 FIG. is a schematic cross-sectional view showing an example of a fringe field switching (FFS) mode lateral electric field liquid crystal display element including a liquid crystal aligning film obtained from the liquid crystal aligning agent of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0041] Hereinafter, a liquid crystal aligning agent containing a specific polymer component, a liquid crystal aligning film formed using the liquid crystal aligning agent, and a liquid crystal display element having the liquid crystal aligning film will be described in detail. However, the description of the constituent elements described below is an example of an embodiment of the present invention and is not limited to these contents.

[0042] In the following description, examples of the "halogen atom" include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. In addition, "tert-" indicating tertiary is also represented as "t-". "Boc" represents tert-butoxycarbonyl, and "*" represents a bonding bond.

[0043] (Terminal amino group)

[0044] The liquid crystal aligning agent of the present invention contains the above-mentioned polymer (A) and polymer (B). At least a part of the terminals of the polyamic acid (A) in the polymer (A) contains a non-amino group, and this non-amino group is the functional group represented by the above structural formula (E). That is, it is preferred that at least a part of the terminal amino groups of the polyamic acid (A) are modified to have this non-amino group.

[0045] Based on all the terminals of the polyamic acid (A), the presence rate of the terminal amino groups of the polyamic acid (A) is preferably 60% or less.

[0046] The "presence rate of terminal amino groups" mentioned here means, for example, in the case of the polyamic acid (A), based on all the terminals of the polyamic acid (A), the ratio of the terminals that are amino groups is expressed in %.

[0047] It should be noted that "based on all the terminals of the polyamic acid (A)" means the case where the total number of amino terminals and non-amino terminals possessed by the polyamic acid (A) is set to 100%, including the total number in the case where any one terminal is 0%.

[0048] The presence rate of the terminal amino groups can be estimated using 1 H-NMR, based on the change amount of the peak intensity of the terminal amino groups. The presence rate of the terminal amino groups of the polyamic acid (A) used in the present invention is preferably 30% or less, more preferably 10% or less, and further preferably 1% or less. In addition, the presence rate of the terminal amino groups of the polyamic acid (A) used in the present invention can also be 0%. That is, all the terminals of the polyamic acid (A) used in the present invention can contain this non-amino group.

[0049] The non-amino group is the functional group represented by the above structural formula (E). Preferably, the functional group represented by the above structural formula (E) is preferably bonded to the nitrogen atom possessed by the diamine residue.

[0050] As preferred specific examples of the above (e1), the following can be cited: methyl, ethyl, propyl, butyl, pentyl, hexyl, vinyl, allyl, methallyl.

[0051] As preferred specific examples of the above (e1), the following can be cited: residues derived from acyclic aliphatic dicarboxylic anhydrides such as acetic anhydride, acrylic anhydride, methacrylic anhydride, propionic anhydride, butyric anhydride, valeric anhydride, isovaleric anhydride, hexanoic anhydride or heptanoic anhydride.

[0052] As preferred specific examples of the above (e2), the following can be cited: monovalent organic groups having a residue derived from a dicarboxylic anhydride and having 1 to 2 carboxyl groups.

[0053] Specific examples of the dicarboxylic anhydride that provides the above (e2) include a compound (e2-1) that does not have an alkoxysilane structure and a compound (e2-2) that has an alkoxysilane structure.

[0054] Specific examples of the compound (e2-1) include aromatic or aliphatic cyclic dicarboxylic anhydrides such as phthalic anhydride, maleic anhydride, succinic anhydride, allyl succinic anhydride, itaconic anhydride, trimellitic anhydride, 1,2,4-cyclohexanetricarboxylic-1,2-anhydride, 4-ethynylphthalic anhydride, or cyclohexene-1,2-dicarboxylic anhydride.

[0055] The aliphatic ring in the above aliphatic cyclic dicarboxylic anhydride may be a saturated aliphatic ring or an unsaturated aliphatic ring.

[0056] Specific examples of the compound (e2-2) include: 3-trimethoxysilylpropyl succinic anhydride, 3-triethoxysilylpropyl succinic anhydride, 4-(3-trimethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-triethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-trimethoxysilylpropyl)phthalic anhydride, 4-(3-triethoxysilylpropyl)phthalic anhydride; (C1-C6) alkoxydimethylsilyl (C2-C8) alkyl succinic anhydrides such as 2-(methoxydimethylsilyl)ethyl succinic anhydride, 3-(dimethylmethoxysilyl)propyl succinic anhydride, or 3-(dimethylethoxysilyl)propyl succinic anhydride; bis(C1-C6) alkoxymethylsilyl (C2-C8) alkyl succinic anhydrides such as 2-(dimethoxymethylsilyl)ethyl succinic anhydride; tris(C1-C6) alkoxysilyl (C2-C8) alkyl succinic anhydrides such as 2-(trimethoxysilyl)ethyl succinic anhydride, 2-(triethoxysilyl)ethyl succinic anhydride, [3-(trimethoxysilyl)propyl]succinic anhydride, or [3-(triethoxysilyl)propyl]succinic anhydride; iced 4-(3-dimethylmethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-dimethylethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-dimethylmethoxysilylpropyl)phthalic anhydride, or 4-(3-dimethylethoxysilylpropyl)phthalic anhydride.

[0057] <Polyamic acid (A)>

[0058] (Structural unit derived from a tetracarboxylic acid derivative possessed by the polyamic acid (A))

[0059] As the polyamic acid (A) in the polymer (A) of the present invention has the above formula (1T a) The structural unit (a-1Ta) shown is used as the structural unit derived from the tetracarboxylic acid derivative. It should be noted that the polymer (A) can be composed of one or more than two kinds, and the structural unit (a-1Ta) can also be one or more than two kinds.

[0060] X in the above formula (1T a ) a represents the tetravalent organic group shown in the above formula (x-1).

[0061] As specific examples of the alkyl group having 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, among R1 to R4 in the above formula (x-1), the following can be cited: methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, etc. As specific examples of the alkenyl group having 2 to 6 carbon atoms, preferably 2 to 4 carbon atoms, among R1 to R4, the following can be cited: vinyl, propenyl, butenyl, etc., which can be linear or branched. As specific examples of the alkynyl group having 2 to 6 carbon atoms, preferably 2 to 4 carbon atoms, among R1 to R4, for example, the following can be cited: ethynyl, 1-propynyl, 2-propynyl, etc.

[0062] As the monovalent organic group having 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, containing a fluorine atom, among R1 to R4, the following can be cited: fluoromethyl, trifluoromethyl, trifluoromethoxy, 2,2,2-trifluoroethyl, 2,2,2-trifluoroethoxy, pentafluoroethyl, pentafluoropropyl, etc.

[0063] Regarding the above formula (x-1), preferably, it is selected from the group consisting of the following formulas (x1-1) to (x1-5).

[0064]

[0065] From the viewpoint of appropriately obtaining the effects of the present invention, relative to 1 mole of all the structural units derived from the tetracarboxylic acid derivative that the polyamic acid (A) has, the structural unit (a-1Ta) that the polyamic acid (A) of the present invention has is preferably 60 mol% or more, more preferably 70 mol% or more.

[0066] In addition, relative to 1 mole of all the structural units derived from the tetracarboxylic acid derivative that the polyamic acid (A) has, the structural unit (a-1Ta) that the polyamic acid (A) of the present invention has can be 100 mol% or less, can be 95 mol% or less, or can be 90 mol% or less.

[0067] The polyamic acid (A) of the present invention optionally has the structural unit (a-2Ta) shown in the following formula (2T a ) as the structural unit derived from the tetracarboxylic acid derivative. The structural unit (2-1Ta) can be one or more than two kinds.

[0068]

[0069] (In the formula, X a represents a tetravalent organic group derived from a tetracarboxylic dianhydride other than the tetravalent organic group represented by the above formula (x-1).)

[0070] As the X a in the above formula (2T 2a ), specific examples of the tetravalent organic group include a tetravalent organic group (T 5a ) having an alicyclic structure with a five-membered ring or more, or a tetravalent organic group obtained by removing two acid anhydride groups from the following tetracarboxylic dianhydrides (hereinafter, these are also collectively referred to as other tetracarboxylic dianhydrides).

[0071] Acyclic aliphatic tetracarboxylic dianhydrides such as 1,2,3,4-butane tetracarboxylic dianhydride, or tetracarboxylic dianhydrides represented by the following formulas (AL-1) to (AL-7); Alicyclic tetracarboxylic dianhydrides such as 1,2,3,4-cyclobutane tetracarboxylic dianhydride (excluding tetracarboxylic dianhydrides having a tetravalent organic group (T 5a )); and tetracarboxylic dianhydrides described in Japanese Patent Laid-Open No. 2010-97188, etc.

[0072]

[0073] More preferable examples of the above other tetracarboxylic dianhydrides include 1,2,3,4-butane tetracarboxylic dianhydride and 1,2,3,4-cyclobutane tetracarboxylic dianhydride.

[0074] As the above tetravalent organic group (T 5a ), a tetravalent organic group having an alicyclic structure with a five- to eight-membered ring is preferable, and a tetravalent organic group having an alicyclic structure with a five- to seven-membered ring is more preferable. It should be noted that the alicyclic structure with a five-membered ring or more means that when the alicyclic structure to which the acid anhydride group is bonded is a polycyclic structure, in each ring included in the polycyclic structure, the number of atoms constituting the ring is 5 or more. In addition, the alicyclic structure only needs to be bonded to at least one of the two acid anhydride groups, and may also have a chain hydrocarbon structure and an aromatic ring structure together with the alicyclic structure.

[0075] As a preferable specific example of the tetravalent organic group (T 5a ), a tetravalent organic group represented by any one of the following formulas (X 5a -1) to (X 5a -18) can be cited. From the viewpoint of appropriately obtaining the effects of the present invention, the tetravalent organic group (T 5a ) is more preferably (X 5a -1) to (X 5a -4).

[0076]

[0077] Per 1 mole of all the structural units derived from the tetracarboxylic acid derivative in the polyamic acid (A), the proportion of the structural unit represented by the formula (2T a ) in the polyamic acid (A) is preferably 40 mol% or less, more preferably 30 mol% or less.

[0078] Per 1 mole of all the structural units derived from the tetracarboxylic acid derivative in the polyamic acid (A), the proportion of the structural unit represented by the formula (2T a ) in the polyamic acid (A) can be 5 mol% or more, and can also be 10 mol% or more.

[0079] (The structural unit derived from diamine in the polyamic acid (A))

[0080] The polyamic acid (A) in the polymer (A) of the present invention has the structural unit (a-1Da) represented by the above formula (1Da) as the structural unit derived from diamine. The structural unit (a-1Da) can be one or two or more.

[0081] As the monovalent organic group of Z in the above formula (1D a ), examples include: a monovalent hydrocarbon group having 1 to 6 carbon atoms; a monovalent group A obtained by substituting the methylene group of the hydrocarbon group with -O-, -S-, -CO-, -COO-, -COS-, -NR 3 -, -CO-NR 3 -, -Si(R 3 )2- (where R 3 represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbon atoms), -SO2- and the like; a monovalent group obtained by substituting at least one hydrogen atom bonded to a carbon atom of the above monovalent hydrocarbon group or the above monovalent group A with a halogen atom, a hydroxyl group, an alkoxy group, a nitro group, an amino group, a mercapto group, a nitroso group, an alkylsilyl group, an alkoxysilyl group, a silanol group, a sulfino group, a phosphino group, a carboxyl group, a cyano group, a sulfo group, an acyl group, etc.; a monovalent group having a heterocycle.

[0082] As the monovalent organic group of Z in the above formula (1D a ), among them, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms or a tert-butoxycarbonyl group is preferred, and an alkyl group having 1 to 3 carbon atoms is more preferred, and methyl is still more preferred.

[0083] From the viewpoint of appropriately obtaining the effects of the present invention, the two Zs in the above formula (1D a ) are each independently preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably a hydrogen atom or a methyl group.

[0084] As a preferred structural unit of the above structural unit (a-1Da), there can be cited a structural unit (1D-1) derived from the diamine (0) "H-N(Z)-Ar1-L1-A-L 1’ -Ar 1’ -N(Z)-H", or a structural unit (1D-2) derived from a diamine other than the above diamine (0) (hereinafter, also referred to as other diamine).

[0085] Here, Ar1 and Ar 1’ each independently represent a benzene ring, a biphenyl structure or a naphthalene ring. Any hydrogen atom on the rings of Ar1 and Ar 1’ is optionally substituted by a monovalent group. A represents a divalent organic group having an alkylene structure and having 1 to 10 carbon atoms.

[0086] L1 and L 1’ each independently represent a single bond, -O-, -S-, -C(=O)-, -O-C(=O)-, -C(=O)-NR-(R represents a hydrogen atom or a monovalent organic group), or -NR-C(=O)-(R represents a hydrogen atom or a monovalent organic group).

[0087] (Diamine (0))

[0088] As the monovalent organic group of R in -C(=O)-NR- or -NR-C(=O)- representing L1 and L 1’ in the above diamine (0), there can be cited: an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, an alkenyl group having 2 to 3 carbon atoms, an acyl group having 2 to 3 carbon atoms, an alkylsilyl group having 1 to 3 carbon atoms, an alkoxysilyl group having 1 to 3 carbon atoms, and a monovalent organic group formed by substituting at least a part of the hydrogen atoms of these groups with at least any one of a halogen atom and a hydroxyl group.

[0089] As the monovalent group as a substituent of any hydrogen atom on the rings of Ar1 and Ar 1’ in the above diamine (0), there can be cited: a halogen atom; an alkyl group having 1 to 3 carbon atoms; an alkyl group having 1 to 3 carbon atoms formed by substituting at least a part of the hydrogen atoms with a halogen atom or a hydroxyl group; an alkoxy group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms formed by substituting at least a part of the hydrogen atoms with at least any one of the above halogen atom and a hydroxyl group; an alkenyl group having 2 to 3 carbon atoms; an acyl group having 2 to 3 carbon atoms; an alkylsilyl group having 1 to 3 carbon atoms; an alkoxysilyl group having 1 to 3 carbon atoms; a monovalent group such as a hydroxyl group and a nitrile group.

[0090] As Ar1 and Ar 1’Specific examples thereof include: optionally substituted benzene rings such as 1,4-phenylene, 1,3-phenylene, 2-methyl-1,4-phenylene, 2-ethyl-1,4-phenylene, 2-propyl-1,4-phenylene, 2-butyl-1,4-phenylene, 2-isopropyl-1,4-phenylene, 2-tert-butyl-1,4-phenylene, 2-methoxy-1,4-phenylene, 2-ethoxy-1,4-phenylene, 2-propoxy-1,4-phenylene, 2-butoxy-1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-dimethyl-1,4-phenylene, 4-methyl-1,3-phenylene, 5-methyl-1,3-phenylene, 4-fluoro-1,3-phenylene, 2,3,5,6-tetramethyl-1,4-phenylene; biphenyl structures such as 4,4'-biphenylene, 2-methyl-4,4'-biphenylene, 2-ethyl-4,4'-biphenylene, 2-propyl-4,4'-biphenylene, 2-butyl-4,4'-biphenylene, 2-tert-butyl-4,4'-biphenylene, 2-methoxy-4,4'-biphenylene, 2-ethoxy-4,4'-biphenylene, 2-fluoro-4,4'-biphenylene, 3-methyl-4,4'-biphenylene, 3-ethyl-4,4'-biphenylene, 3-propyl-4,4'-biphenylene, 3-butyl-4,4'-biphenylene, 3-tert-butyl-4,4'-biphenylene, 3-methoxy-4,4'-biphenylene, 3-ethoxy-4,4'-biphenylene, 3-fluoro-4,4'-biphenylene, 2,2'-dimethyl-4,4'-biphenylene, 3,3'-dimethyl-4,4'-biphenylene, 3,3'-biphenylene, 5-methyl-3,3'-biphenylene, 5,5'-dimethyl-3,3'-biphenylene, etc., which are optionally substituted; naphthalene rings such as 1,5-naphthylene, 2,6-naphthylene, 1-methyl-2,6-naphthylene, etc., which are optionally substituted.

[0091] In the above diamine (0), A is a divalent organic group having an alkylene structure and having 1 to 10 carbon atoms. When the alkylene structure has three or more carbon-carbon bonds, any carbon-carbon bond constituting the alkylene structure may be replaced by a carbon-carbon double bond. A is preferably an alkylene group (q0) having 1 to 10 carbon atoms; a divalent organic group (q1) formed by inserting -O-, -C(=O)-, -NH-, -O-C(=O)- or -C(=O)-O- between the carbon-carbon bonds of the alkylene group; or a divalent organic group (q2) having at least one -NR-C(=O)-NR- (R represents a hydrogen atom or a monovalent organic group) between the carbon-carbon bonds of the alkylene group.

[0092] Here, as the monovalent organic group of R in the above -NR-C(=O)-NR-, the monovalent organic groups represented by L1 and L in the above diamine (0) can be cited. 1’The structures exemplified for R in -C(=O)-NR-.

[0093] Preferred specific examples of the above (q0), (q1), and (q2) are as follows.

[0094] *-(CH2) n -*.

[0095] *-(CH2) n1 -O-(CH2) n2 -*.

[0096] *-(CH2) m1 -O-C(=O)-(CH2) n’ -C(=O)-O-(CH2) m2 -*.

[0097] *-(CH2) m1 -C(=O)-O-(CH2) n’ -O-C(=O)-(CH2) m2 -*.

[0098] *-(CH2) n1 -NR-C(=O)-NR-(CH2) n2 -*.

[0099] In the above chemical formulas, R represents a hydrogen atom or a monovalent organic group. As the monovalent organic group, the structures exemplified for R in -C(=O)-NR- of the above diamine (0) can be cited for L1 and L 1’ The structures exemplified for R in -C(=O)-NR-. The two Rs are optionally the same or different from each other.

[0100] n is an integer from 1 to 10, more preferably an integer from 2 to 10, and even more preferably an integer from 2 to 6.

[0101] m1 and m2 are each independently an integer from 0 to 4, n' is an integer from 1 to 6, and the sum of m1, m2, and n' is from 1 to 8.

[0102] *-(CH2) n1 -O-(CH2) n2 In -* where n1 and n2 are each independently an integer from 1 to 6, and the sum of n1 and n2 is from 2 to 10.

[0103] *-(CH2) n1 -NR-C(=O)-NR-(CH2) n2 In -* where n1 and n's are each independently an integer from 1 to 6, and the sum of n1 and n2 is from 2 to 9. [[ID=E7]]

[0104] From the viewpoint of appropriately obtaining the effects of the present invention, *-L1-A-L 1’ -* preferably adopts the following scheme. In the following formula, the definitions of m1, m2, n, n', n1, and n2 are the same as those in the above formula. In addition, R in the following formula represents a hydrogen atom or a monovalent organic group. When there are two Rs, they each independently have the above definition. As the above monovalent organic group, the structures exemplified for R in -C(=O)-NR- in the above formula (H1) and L 1’ can be cited.

[0105] *- (CH2) n -*, -O-(CH2) n -O-*.

[0106] *-O-(CH2) n1 -O-(CH2) n2 -O-*.

[0107] *-C(=O)-(CH2) n -C(=O)-*.

[0108] *-C(=O)-NR-(CH2) n -O-*.

[0109] *-O-C(=O)-(CH2) n -O-*.

[0110] *-O-C(=O)-(CH2) n -O-C(=O)-*.

[0111] *-O-C(=O)-(CH2) n -C(=O)-O-*.

[0112] *-(CH2) m1 -O-C(=O)-(CH2) n’ -C(=O)-O-(CH2) m2 -*. [[ID=5))

[0113] *-S-(CH2) n -S-*.

[0114] *-C(=O)-NR-(CH2) n -NR-C(=O)-*.

[0115] *-C(=O)-O-(CH2) n -O-C(=O)-*.

[0116] *-(CH2) m1 -C(=O)-O-(CH2)n’ -O-C(=O)-(CH2) m2 -*。

[0117] * - O-(CH2) n -*、* - S-(CH2) n -*。

[0118] * - NR-C(=O)-(CH2) n -C(=O)-NR-*。

[0119] * -(CH2) n1 -NR-C(=O)-NR-(CH2) n2 -*。

[0120] Furthermore, from the viewpoint of appropriately obtaining the effects of the present invention, * -(CH2) n -*、* - O-(CH2) n -O-*、* - O-(CH2) n -*。

[0121] The polyamic acid (A) may also contain at least one: Y[[ID=3�]] a A divalent organic group having three or more benzene rings, i.e., the structural unit represented by the above formula (1D a ) as a structural unit derived from diamine.

[0122] Here, the benzene rings in the "divalent organic group having three or more benzene rings" also include the benzene rings constituting the condensed rings. And when counting the number of benzene rings in the above diamine (0), the counting is carried out as follows: a naphthalene ring is assumed to have two benzene rings, an anthracene ring is assumed to have three benzene rings, and a biphenyl structure is assumed to have two benzene rings.

[0123] From the viewpoint of appropriately obtaining the effects of the present invention, the above structural unit (1D-1) preferably has a divalent organic group represented by any one of the following formulas (h1-1) to (h1-14).

[0124] In the formulas (h1-1) to (h1-14), the bonding positions of the benzene rings are preferably the 1-position and the 4-position, and the bonding positions of the naphthalene rings are preferably the 2-position and the 6-position.

[0125] In the formula (h1-4), the total number of -CH2- is 10 or less.

[0126] In the formulas (h1-7), (h1-8), (h1-14), the total number of -CH2- is 8 or less, and the two m are optionally the same as or different from each other.

[0127] It should be noted that the hydrogen atoms on the benzene ring of the following formulas (h1-1) to (h1-14) are optionally substituted with methyl groups, methoxy groups, or fluorine atoms.

[0128]

[0129] In one embodiment, in the polyamic acid (A), relative to 1 mole of all the structural units derived from diamine that the polyamic acid (A) has, the above structural unit (1D-1) preferably contains 5 mol% or more, more preferably 10 mol% or more, and still more preferably 20 mol% or more. Further, in the polyamic acid (A), relative to 1 mole of all the structural units derived from diamine that the polyamic acid (A) has, the above structural unit (1D-1) may be 100 mol% or less, may be 95 mol% or less, may be 90 mol% or less, or may be 80 mol% or less.

[0130] Examples of the other diamines as the structural units (1D-2) derived from the above other diamines include the following substances.

[0131] p-Phenylenediamine, 2,3,5,6-Tetramethyl-p-phenylenediamine, 2,5-Dimethyl-p-phenylenediamine, m-Phenylenediamine, 2,4-Dimethyl-m-phenylenediamine, 1,4-Diamino-2,5-dimethoxybenzene, 2,5-Diaminotoluene, 2,6-Diaminotoluene, 4-Aminobenzylamine, 2-(4-Aminophenyl)ethylamine, semi-aromatic diamines having a secondary amino group and a primary amino group (preferably 4-(2-(methylamino)ethyl)aniline) (here, semi-aromatic diamines refer to diamines in which one amino group is bonded to an aromatic ring and the other amino group is not bonded to an aromatic ring), 4-(2-Aminoethyl)aniline, 2-(6-Aminonaphthyl)ethylamine, 2,2'-Dimethyl-4,4'-diaminobiphenyl, 3,3'-Dimethyl-4,4'-diaminobiphenyl, 3,3'-Dimethoxy-4,4'-diaminobiphenyl, 3,3'-Dihydroxy-4,4'-diaminobiphenyl, 3-Trifluoromethyl-4,4'-diaminobiphenyl, 2-Trifluoromethyl-4,4'-diaminobiphenyl, 3-Fluoro-4,4'-diaminobiphenyl, 2-Fluoro-4,4'-diaminobiphenyl, 2,2'-Difluoro-4,4'-diaminobiphenyl, 3,3'-Difluoro-4,4'-diaminobiphenyl, 2,2'-Bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,3'-Bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,4'-Diaminobiphenyl, 4,4'-Diaminobiphenyl, 3,3'-Diaminobiphenyl, 2,2'-Diaminobiphenyl, 2,3'-Diaminobiphenyl, 1,5-Diaminonaphthalene, 1,6-Diaminonaphthalene, 1,7-Diaminonaphthalene, 2,5-Diaminonaphthalene, 2,6-Diaminonaphthalene, 2,7-Diaminonaphthalene and other specific diamines (hereinafter, they are also referred to as specific diamines (1)).

[0132] 1,4-phenylene bis(4-aminobenzoate), 1,4-phenylene bis(3-aminobenzoate), 1,3-phenylene bis(4-aminobenzoate), 1,3-phenylene bis(3-aminobenzoate), bis(4-aminophenyl) terephthalate, bis(3-aminophenyl) terephthalate, bis(4-aminophenyl) isophthalate, bis(3-aminophenyl) isophthalate; diamines having a photo-orienting group such as aromatic diamines having a cinnamate structure represented by 4,4'-diaminoazobenzene, diaminodiphenylacetylene, 4,4-diaminochalcone, or [4-[(E)-3-[2-(2,4-diaminophenyl)ethoxy]-3-oxo-prop-1-enyl]phenyl] 4-(4,4,4-trifluorobutoxy)benzoate or [4-[(E)-3-[[5-amino-2-[4-amino-2-[[(E)-3-[4-[4-(4,4,4-trifluorobutoxy)benzoyl]oxyphenyl]prop-2-enoyl]oxymethyl]phenyl]phenyl]methoxy]-3-oxo-prop-1-enyl]phenyl] 4-(4,4,4-trifluorobutoxy)benzoate; diamines having a photopolymerizable group at the terminal such as 2-(2,4-diaminophenoxy)ethyl methacrylate or 2,4-diamino-N,N-diallylaniline; diamines having a function of a radical polymerization initiator such as 1-(4-(2-(2,4-diaminophenoxy)ethoxy)phenyl)-2-hydroxy-2-methylpropanone, 2-(4-(2-hydroxy-2-methylpropanoyl)phenoxy)ethyl 3,5-diaminobenzoate; diamines having an amide bond such as 4,4'-diaminobenzanilide; diamines having a urea bond such as 1,3-bis(4-aminophenyl)urea; H2N-Y D -NH2 (Y D represents a divalent organic group having -N(D)- (D represents a protecting group that is detached by heating and replaced with a hydrogen atom) in the molecule), etc., diamines having a thermally detachable group.

[0133] 3,3'-Diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(4-aminophenoxy)diphenyl ether, 1,4-bis[4-(4-aminophenoxy)phenoxy]benzene, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 4,4'-sulfonyldianiline, 3,3'-sulfonyldianiline, bis(4-aminophenyl)silane, bis(3-aminophenyl)silane, dimethyl-bis(4-aminophenyl)silane, dimethyl-bis(3-aminophenyl)silane, 4,4'-thiodianiline, 3,3'-thiodianiline, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 2,2'-bis[4-(4-aminophenoxy)phenyl]propane, 2,2'-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2'-bis(4-aminophenyl)hexafluoropropane, 2,2'-bis(3-aminophenyl)hexafluoropropane, 2,2'-bis(3-amino-4-methylphenyl)hexafluoropropane, 2,2'-bis(4-aminophenyl)propane, 2,2'-bis(3-aminophenyl)propane, 2,2'-bis(3-amino-4-methylphenyl)propane, 4,4'-diaminobenzophenone, 1,4-bis(4-aminobenzyl)benzene;2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, 1,4-bis(4-aminophenyl)piperazine, 3,6-diaminoacridine, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, N-(3-(1H-imidazol-1-yl)propyl)-3,5-diaminobenzamide, 4-[4-[(4-aminophenoxy)methyl]-4,5-dihydro-4-methyl-2-oxazolyl]-aniline, 4-[4-[(4-aminophenoxy)methyl]-4,5-dihydro-2-oxazolyl]-aniline, 1,4-bis(p-aminobenzyl)piperazine, 4,4'-[4,4'-propane-1,3-diyldi(piperidine-1,4-diyl)]diphenylamine, 4-(4-aminophenoxycarbonyl)-1-(4-aminophenyl)piperidine, 2,5-bis(4-aminophenyl)pyrrole, 4,4'-(1-methyl-1H-pyrrole-2,5-diyl)bis[aniline], 1,4-bis(4-aminophenyl)piperazine, 2-N-(4-aminophenyl)pyridine-2,5-diamine, 2-N-(5-aminopyridin-2-yl)pyridine-2,5-diamine, 2-(4-aminophenyl)-5-aminobenzimidazole, 2-(4-aminophenyl)-6-aminobenzimidazole, 5-(1H-benzimidazol-2-yl)benzene-1,3-diamine or a heterocyclic diamine such as a diamine represented by the following formula (z-1) to formula (z-5), or 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, etc., a diamine having a diphenylamine structure, having at least one nitrogen atom-containing structure selected from the group consisting of a nitrogen atom-containing heterocycle, a secondary amino group or a tertiary amino group (wherein, an amino group derived from -N(D)- (D represents a protecting group that is removed by heating and replaced with a hydrogen atom) is excluded. Hereinafter, it is also referred to as a specific nitrogen atom-containing structure. Among them, the specific nitrogen atom-containing structure is a group other than the two amino groups participating in the polycondensation reaction).;

[0134] 2,4-diaminophenol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, 4,4'-diamino-3,3'-dihydroxybiphenyl; 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 3,5-diaminobenzoic acid, 4,4'-diaminobiphenyl-3-carboxylic acid, 4,4'-diaminodiphenylmethane-3-carboxylic acid, 4,4'-diaminodiphenylethane-3-carboxylic acid, 4,4'-diaminobiphenyl-3,3'-dicarboxylic acid, 4,4'-diaminobiphenyl-2,2'-dicarboxylic acid, 3,3'-diaminobiphenyl-4,4'-dicarboxylic acid, 3,3'-diaminobiphenyl-2,4'-dicarboxylic acid, 4,4'-diaminodiphenylmethane-3,3'-dicarboxylic acid, 4,4'-diaminodiphenylethane-3,3'-dicarboxylic acid, 4,4'-diaminodiphenyl ether-3,3'-dicarboxylic acid and other diamines having a carboxyl group; 1-(4-aminophenyl)-1,3,3-trimethyl-1H-indan-5-amine, 1-(4-aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H-indene-6-amine; cholesteryloxy-3,5-diaminobenzene, cholestenyloxy-3,5-diaminobenzene, cholesteryloxy-2,4-diaminobenzene, cholesteryl 3,5-diaminobenzoate, cholestenyl 3,5-diaminobenzoate, lanosterol 3,5-diaminobenzoate and 3,6-bis(4-aminobenzoyloxy)cholestane and other diamines having a steroid skeleton; diamines represented by the following formulas (V-1) to (V-2); 1,3-bis(3-aminopropyl)-tetramethyldisiloxane and other diamines having a siloxane bond; m-xylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine and other acyclic aliphatic diamines; 1,3-bis(aminomethyl)cyclohexane, 1,4-diaminocyclohexane, 4,4'-methylenebis(cyclohexylamine) and other cycloaliphatic diamines; diamines formed by bonding two amino groups to a group represented by any one of the formulas (Y-1) to (Y-167) described in WO2018 / 117239, etc.

[0135]

[0136] (In formula (V-1), m and n are integers from 0 to 3 (where 1 ≤ m + n ≤ 4), j is an integer of 0 or 1, and X 1 is -(CH2) a -(a is an integer from 1 to 15), -CONH-, -NHCO-, -CO-N(CH_3)-, -NH-, -O-, -CH2O-, -CH2-OCO-, -COO- or -OCO-. R 1represents a fluorine atom, a fluorine-containing alkyl group having 1 to 10 carbon atoms, a fluorine-containing alkoxy group having 1 to 10 carbon atoms, an alkyl group having 3 to 10 carbon atoms, an alkoxy group having 3 to 10 carbon atoms, or an alkoxyalkyl group having 3 to 10 carbon atoms. In formula (V-2), X 2 represents -O-, -CH2O-, -CH2-OCO-, -COO-, or -OCO-. In formulas (z-2), (V-1), and (V-2), when there are two m, n, X 1 , R 1 , they each independently have the above definitions.)

[0137] It should be noted that D in -N(D)- of the above diamine having a thermally detachable group is preferably a carbamate-based organic group represented by benzyloxycarbonyl, 9-fluorenylmethoxycarbonyl, allyloxycarbonyl, Boc group, etc. From the viewpoint of good efficiency of thermal detachment, detachment at a lower temperature, and discharge as a harmless gas during detachment, the Boc group is particularly preferred.

[0138] As a preferred example of the diamine having a thermally detachable group exemplified by the above other diamines, a diamine selected from the following formulas (d Da -1) to (d Da -8) is preferred.

[0139]

[0140] (In formulas (d Da -2), (d Da -6), and (d Da -7), R represents a hydrogen atom or a Boc group.)

[0141] In one aspect, when the polyamic acid (A) used in the present invention has the above structural unit (1D-2), from the viewpoint of appropriately obtaining the effects of the present invention, it is more preferably to contain a structural unit derived from the above specific diamine (1).

[0142] Relative to 1 mole of all the structural units derived from diamine contained in the polyamic acid (A), the structural unit derived from the above specific diamine (1) is preferably 5 mol% or more, more preferably 10 mol% or more, and further preferably 20 mol% or more. Relative to 1 mole of all the structural units derived from diamine contained in the polyamic acid (A), the structural unit derived from the above specific diamine (1) is preferably 95 mol% or less, more preferably 90 mol% or less, and further preferably 80 mol% or less.

[0143] In addition, from the viewpoint of improving the bilayer separation between the two polymers, the polyamic acid (A) may also contain a structural unit derived from a diamine having the above-mentioned thermally detachable group as the above-mentioned structural unit (1D-2). With respect to 1 mole of all the structural units derived from diamines contained in the polyamic acid (A), the structural unit derived from the diamine having the above-mentioned thermally detachable group is preferably 5 to 40 mol%, more preferably 5 to 35 mol%, and still more preferably 5 to 30 mol%.

[0144] Furthermore, from the viewpoint of appropriately obtaining the effects of the present invention, the polyamic acid (A) preferably contains a structural unit derived from the following other diamine as the above-mentioned structural unit (1D-2), the other diamine being a diamine other than the diamine having the above-mentioned thermally detachable group and having no side chain group with 3 or more carbon atoms.

[0145] Here, examples of the diamine having a side chain group with 3 or more carbon atoms include: the above-mentioned diamine having a photo-orienting group and having a side chain group with 3 or more carbon atoms; the above-mentioned diamine having a photo-polymerizable group at the terminal and having a side chain group with 3 or more carbon atoms; the above-mentioned diamine having a free radical polymerization initiator function and having a side chain group with 3 or more carbon atoms; the above-mentioned diamine having a specific nitrogen atom-containing structure and having a side chain group with 3 or more carbon atoms; the above-mentioned diamine having a steroid skeleton; the above-mentioned diamines represented by the above formulas (V-1) to (V-2) and having a side chain group with 3 or more carbon atoms, etc.

[0146] <Polyamic acid (B)>

[0147] (Structural unit derived from tetracarboxylic acid derivative possessed by polyamic acid (B))

[0148] The liquid crystal aligning agent of the present invention optionally contains the following polyamic acid (B) together with the above-mentioned polyamic acid (A), the polyamic acid (B) having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, and containing the above-mentioned formula (1T b ) shown structural unit (b-1Tb) as the structural unit derived from the tetracarboxylic acid derivative. It should be noted that the polyamic acid (A) and the polyamic acid (B) are different polymers.

[0149] The polyamic acid (B) may be optionally composed of one or more than two kinds. In addition, the above-mentioned structural units constituting the polyamic acid (B) may be respectively composed of one or more than two kinds.

[0150] As for providing X of the above formula (1T b ) bRegarding the tetravalent organic group, examples thereof include a tetravalent organic group formed by removing two anhydride groups (—C(═O)—O—C(═O)—) from an aromatic tetracarboxylic dianhydride, or a tetravalent organic group formed by removing two anhydride groups from a tetracarboxylic dianhydride having the above-mentioned tetravalent organic group (T 5a ).

[0151] Here, the aromatic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxyl groups including at least one carboxyl group bonded to an aromatic ring.

[0152] From the viewpoint of appropriately achieving the effects of the present invention, the tetravalent organic group derived from the above aromatic tetracarboxylic dianhydride is preferably a tetracarboxylic dianhydride having a benzene ring. More preferably, the tetravalent organic group derived from the aromatic tetracarboxylic dianhydride in X b is a tetravalent organic group formed by removing two anhydride groups from the following aromatic tetracarboxylic dianhydrides.

[0153] Pyromellitic dianhydride, 3,3′,4,4′-benzophenone tetracarboxylic dianhydride, 3,3′,4,4′-diphenyl sulfone tetracarboxylic dianhydride, 1,4,5,8-naphthalene tetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 3,3′,4,4′-diphenyl ether tetracarboxylic dianhydride, 3,3′,4,4′-perfluoroisopropylidene bis(phthalic anhydride), 3,3′,4,4′-biphenyl tetracarboxylic dianhydride, 2,2′,3,3′-biphenyl tetracarboxylic dianhydride, 4,4′-bis(3,4-dicarboxyphenoxy)-2,2-diphenylpropane dianhydride, ethylene glycol bisanhydrotrimellitate, 4,4′-(hexafluoroisopropylidene)diphthalic anhydride, 4,4′-carbonyldiphthalic anhydride, 4,4′-oxydi(1,4-phenylene)bis(phthalic acid) dianhydride, or 4,4′-methylenedi(1,4-phenylene)bis(phthalic acid) dianhydride and other aromatic tetracarboxylic dianhydrides.

[0154] As a preferred specific example of the above tetravalent organic group (T 5a ), a tetravalent organic group (T 5a ) having an alicyclic structure with a five-membered ring or more, as exemplified in the polyamic acid (A), can be mentioned.

[0155] From the viewpoint of appropriately achieving the effects of the present invention, relative to 1 mole of all the structural units derived from the tetracarboxylic acid derivative that the polyamic acid (B) has, the polyamic acid (B) preferably contains more than 40 mol% of the structural unit (b-1Tb), and more preferably contains 50 mol% or more of the structural unit (b-1Tb).

[0156] The polyamic acid (B) of the present invention optionally has a structural unit (b-2Tb) represented by the following formula (2T b ) as a structural unit derived from the tetracarboxylic acid derivative.

[0157]

[0158] (In the formula, X 2b represents a tetravalent organic group other than X b .)

[0159] As specific examples of the tetravalent organic group as X b in the above formula (2T 2b ), there may be mentioned a tetravalent organic group obtained by removing two acid anhydride groups from an acyclic aliphatic tetracarboxylic dianhydride, or a tetravalent organic group obtained by removing two acid anhydride groups from an alicyclic tetracarboxylic dianhydride.

[0160] Here, the acyclic aliphatic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxyl groups bonded to a chain hydrocarbon structure. Among them, it is not necessary to be composed only of a chain hydrocarbon structure, and an alicyclic structure or an aromatic ring structure may be present in a part thereof.

[0161] The alicyclic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxyl groups including at least one carboxyl group bonded to an alicyclic structure. Among them, none of these four carboxyl groups is bonded to an aromatic ring. In addition, it is not necessary to be composed only of an alicyclic structure, and a chain hydrocarbon structure or an aromatic ring structure may be present in a part thereof.

[0162] From the viewpoint of appropriately obtaining the effects of the present invention, the tetravalent organic group in the above X 2b is preferably a tetravalent organic group obtained by removing two acid anhydride groups from a tetracarboxylic dianhydride having at least one partial structure selected from the group consisting of a cyclobutane ring structure and a cyclobutene ring structure, or a tetravalent organic group obtained by removing two acid anhydride groups from an acyclic aliphatic tetracarboxylic dianhydride exemplified by the above other tetracarboxylic dianhydrides.

[0163] More preferably, examples of X 2b include a tetravalent organic group obtained by removing two acid anhydride groups from cyclobutane tetracarboxylic dianhydride, or a tetravalent organic group obtained by removing two acid anhydride groups from an acyclic aliphatic tetracarboxylic dianhydride exemplified by the above other tetracarboxylic dianhydrides.

[0164] From the viewpoint of appropriately obtaining the effects of the present invention, with respect to 1 mole of all the structural units derived from the tetracarboxylic acid derivative contained in the polyamic acid (B), the polyamic acid (B) preferably contains less than 60 mol% of the structural unit (b - 2Tb), and more preferably contains 50 mol% or less of the structural unit (b - 2Tb).

[0165] (Structural unit derived from diamine possessed by polyamic acid (B))

[0166] The polyamic acid (B) has the above structural unit (b-1Db1), the above structural unit (b-1Db2), and the above structural unit (b-1Db3) as the structural units derived from diamine.

[0167] With respect to 1 mole of all the structural units derived from diamine that the polyamic acid (B) has, the total proportion of the above structural unit (b-1Db1), the above structural unit (b-1Db2), and the above structural unit (b-1Db3) is preferably 60 mol% or more, more preferably 80 mol% or more.

[0168] In addition, with respect to 1 mole of all the structural units derived from diamine that the polyamic acid (B) has, the total proportion of the above structural unit (b-1Db1), the above structural unit (b-1Db2), and the above structural unit (b-1Db3) can be 100 mol% or less, or can be 90 mol% or less.

[0169] With respect to 1 mole of all the structural units derived from diamine that the polyamic acid (B) has, the proportion of the above structural unit (b-1Db1) is preferably 10 mol% or more, more preferably 20 mol% or more.

[0170] With respect to 1 mole of all the structural units derived from diamine that the polyamic acid (B) has, the proportion of the above structural unit (b-1Db2) is preferably 10 mol% or more, more preferably 20 mol% or more.

[0171] With respect to 1 mole of all the structural units derived from diamine that the polyamic acid (B) has, the proportion of the above structural unit (b-1Db3) is preferably 5 mol% or more, more preferably 10 mol% or more.

[0172] Any hydrogen atom on the benzene ring in the above formula (1D b1 ) to (1D b2 ) is optionally substituted by a monovalent group. Examples of such monovalent group include: halogen atom; alkyl group having 1 to 3 carbon atoms; alkyl group having 1 to 3 carbon atoms in which at least a part of the hydrogen atoms are substituted by halogen atoms or hydroxyl groups; alkoxy group having 1 to 3 carbon atoms, alkoxy group having 1 to 3 carbon atoms in which at least a part of the hydrogen atoms are substituted by at least any one of the above halogen atoms and hydroxyl groups; alkenyl group having 2 to 3 carbon atoms; acyl group having 2 to 3 carbon atoms; alkylsilyl group having 1 to 3 carbon atoms; alkoxysilyl group having 1 to 3 carbon atoms; hydroxyl group, nitrile group, etc.

[0173] Y of the above structural unit (b-1Db3) UThe divalent organic group in it is preferably a divalent organic group derived from a diamine having a urea bond. As preferred examples of the diamine having a urea bond, for example, there can be mentioned: the diamine (0) in which A in the above polymer (A) is a divalent organic group (q2), or the diamine having a urea bond exemplified by the above other diamines, etc.

[0174] The polyamic acid (B) in the polymer (B) of the present invention optionally has a structural unit (b-1Db) shown by the following formula (1D b ) as a structural unit derived from a diamine. The structural unit (b-1Db) can be one kind or two or more kinds. The monovalent organic group of Z in the above formula (1D b ) has the same definition as Z in the above formula (1D a ).

[0175]

[0176] (In the formula (1D b ), Y b represents a divalent organic group of p-phenylenediamine and bis(4-aminophenoxy)methane, and other diamines except for the diamines in which the hydrogen atoms on the benzene ring of these diamines are substituted by monovalent groups and the diamines derived from diamines having a urea bond. Z has the same definition as Z in the above formula (1D a ).)

[0177] As a preferred specific example of the other diamine in the above formula (1D b ), the diamines exemplified by the polyamic acid (A) can be mentioned.

[0178] From the viewpoint of having few afterimages derived from residual DC, in the polyamic acid (B), it is preferred that the above Y b is the following divalent organic group (they are also collectively referred to as "specific divalent organic group (b)"), and this divalent organic group is selected from the group consisting of diamines having the above amide bond, diamines having the above specific nitrogen atom structure, diamines having the above carboxyl group, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, p-phenylenediamine, and m-phenylenediamine, and is obtained by removing two amino groups from the diamines in the group.

[0179] From the viewpoint of having few afterimages derived from residual DC, relative to 1 mole of all the structural units derived from diamines that the polyamic acid (B) has, the polyamic acid (B) can contain 5 mol% or more of the above Y b being the above specific divalent organic group (b) of the formula (1D bThe structural unit (b-1Db) shown can contain 10 mol% or more of the structural unit (b-1Db), and can also contain 20 mol% or more of the structural unit (b-1Db). Further, relative to 1 mol of all the structural units derived from diamine that polyamic acid (B) has, the structural unit (b-1Db) can be 60 mol% or less, and can also be 40 mol% or less.

[0180] Further, from the viewpoint of appropriately obtaining the effects of the present invention, as the above-mentioned structural unit (b-1Db) in polyamic acid (B), other diamines in addition to the above-mentioned diamine having a thermally detachable group are preferred, and these other diamines are structural units derived from diamines having no side chain group with 3 or more carbon atoms.

[0181] As the monovalent organic group of Z in the above formula (1D b ) can be exemplified by the structures exemplified for Z in the above formula (1D a ).

[0182] As one aspect of the liquid crystal aligning agent of the present invention, the following aspect (BL) can be exemplified, but is not limited thereto.

[0183] Aspect (BL) is as follows: in the above polyamic acid (A), relative to 1 mol of all the structural units derived from diamine that polyamic acid (A) has, 5 to 95 mol% of the above structural unit (1D-1) is contained, and in polyamic acid (B), relative to 1 mol of all the structural units derived from diamine that polyamic acid (B) has, 10 mol to 60 mol% of the above structural unit (1D-1) is contained.

[0184] In the liquid crystal aligning agent of the present invention, from the viewpoint of having less afterimage derived from residual DC, the content ratio of polyamic acid (A) and polyamic acid (B) can be 10 / 90 to 90 / 10, can also be 20 / 80 to 90 / 10, and can also be 20 / 80 to 80 / 20 in terms of the mass ratio of [polyamic acid (A) / polyamic acid (B)].

[0185] <Manufacture of polyamic acid>

[0186] The polyamic acid contained in the liquid crystal aligning agent of the present invention can be produced, for example, by the following method.

[0187] By reacting a tetracarboxylic dianhydride component and a diamine component with an amino-terminal modifier added as required, a polymer having an amic acid structure (polyamic acid) is obtained. When the polyamic acid has the structure shown in the above formula (1D a ), for example, as the diamine component, a structure having -N(Z)-Y a -N(Z)- is used (Y a, diamine (where the definition of Z is the same as above), and in addition, as the tetracarboxylic acid derivative component, a tetracarboxylic dianhydride having X a (X a (where the definition is the same as above).

[0188] Regarding the usage ratio of the tetracarboxylic dianhydride and diamine used for the production of polyamic acid, relative to 1 equivalent of the amino group of the diamine, the acid anhydride group of the tetracarboxylic dianhydride is preferably in the ratio of 0.5 to 2 equivalents, more preferably in the ratio of 0.8 to 1.2 equivalents. Similar to the usual polycondensation reaction, the closer the equivalent of the acid anhydride group of the tetracarboxylic dianhydride is to 1 equivalent, the larger the molecular weight of the resulting polyamic acid.

[0189] The reaction temperature for the production of polyamic acid is preferably -20 to 150 °C, more preferably 0 to 100 °C. In addition, the reaction time is preferably 0.1 to 24 hours, more preferably 0.5 to 12 hours.

[0190] The production of polyamic acid can be carried out at any concentration, preferably 1 to 50% by mass, more preferably 5 to 30% by mass. It can also be carried out at a high concentration in the initial stage of the reaction, and then a solvent is added.

[0191] At least a part of the ends of the above polyamic acid (A) contains the above non-amino group. In addition, at least a part of the ends of the above polyamic acid (B) may also contain this non-amino group. This non-amino group can be formed, for example, using an amino-terminal modifier.

[0192] As a preferred specific example of the amino-terminal modifier, the above non-cyclic aliphatic dianhydride, compound (e2-1), or compound (e2-2) can be cited.

[0193] The above polyamic acid (A) and / or polyamic acid (B) can be obtained, for example, by using the following production method (a), production method (b), or a method using both of them.

[0194] Production method (a): A method of polymerizing (polycondensing) a tetracarboxylic dianhydride component, a diamine component, and an amino-terminal modifier.

[0195] Production method (b): A method of reacting a tetracarboxylic dianhydride component with a diamine component to obtain a polymer solution containing an unmodified polyamic acid having an amino-terminal, and then adding an amino-terminal modifier to the polymer solution to cause the ends of the polymer to react.

[0196] In the above production method (b), in order to obtain a polyamic acid having an amino-terminal, in the usage ratio of the tetracarboxylic dianhydride and diamine used for the production of polyamic acid, the usage ratio of the diamine only needs to be above the usage ratio of the tetracarboxylic dianhydride, and the acid anhydride group of the tetracarboxylic dianhydride is preferably 0.5 to 1.0 equivalents relative to 1 equivalent of the amino group of the diamine, more preferably 0.8 to 1.0 equivalents.

[0197] The usage ratio of the amino-terminal modifier is preferably 40 mol parts or less, more preferably 30 mol parts or less, relative to a total of 100 mol parts of the diamine component used.

[0198] In addition, the usage ratio of the amino-terminal modifier is preferably 0.1 mol part, more preferably 0.2 mol part or more, relative to a total of 100 mol parts of the diamine component used.

[0199] The temperature when reacting the amino-terminal modifier with the polyamic acid can be set to the same reaction temperature as that for the production of the polyamic acid, or the reaction can be carried out while heating. As the heating temperature, it is preferably 30 to 80 °C, more preferably 30 to 60 °C. In addition, the reaction time is preferably 0.1 to 24 hours, more preferably 1 to 24 hours.

[0200] Specific examples of the organic solvent used for the production of the above polyamic acid include: cyclohexanone, cyclopentanone, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, 1,3-dimethyl-2-imidazolidinone. In addition, when the solubility of the produced polyamic acid in the solvent is high, solvents such as methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, diethylene glycol monomethyl ether or diethylene glycol monoethyl ether can be used.

[0201] <Solution viscosity / molecular weight of polyamic acid>

[0202] The polyamic acid used in the present invention is preferably a polymer having a solution viscosity of 10 to 1000 mPa·s when made into a solution with a concentration of 10 to 15% by mass, for example, from the viewpoint of operability. It should be noted that the solution viscosity (mPa·s) of the above polymer is a value measured for a polymer solution with a concentration of 10 to 15% by mass prepared with a good solvent (such as γ-butyrolactone, N-methyl-2-pyrrolidone, etc.) of the polymer using an E-type rotational viscometer at 25 °C.

[0203] The polystyrene-reduced weight-average molecular weight (Mw) measured by gel permeation chromatography (GPC) of the above polyamic acid is preferably 1000 to 500000, more preferably 2000 to 300000. In addition, the molecular weight distribution (Mw / Mn) represented by the ratio of Mw to the polystyrene-reduced number-average molecular weight (Mn) measured by GPC is preferably 15 or less, more preferably 10 or less. By being in such a molecular weight range, good alignment and stability of the liquid crystal display element can be ensured.

[0204] The liquid crystal aligning agent of the present invention may also contain other polymers in addition to polymer (A) and polymer (B). Specific examples of the other polymers include at least one polymer (Q) selected from the group consisting of polyimide precursors other than polymer (A) and polymer (B) and polyimides which are imidized products of the polyimide precursors; polymers selected from the group consisting of polysiloxanes, polyesters, polyamides, polyureas, polyorganosiloxanes, cellulose derivatives, polyacetals, polystyrene derivatives, poly(styrene - maleic anhydride) copolymers, poly(isobutylene - maleic anhydride) copolymers, poly(vinyl ether - maleic anhydride) copolymers, poly(styrene - phenylmaleimide) derivatives, and poly(meth)acrylates, etc.

[0205] Specific examples of the poly(styrene - maleic anhydride) copolymer include SMA1000, SMA2000, SMA3000 (manufactured by Cray Valley), GSM301 (manufactured by Gifu Ceramics Works), etc. Specific examples of the poly(isobutylene - maleic anhydride) copolymer include Isobam (manufactured by Kuraray). Specific examples of the poly(vinyl ether - maleic anhydride) copolymer include Gantrez AN - 139 (methyl vinyl ether maleic anhydride resin, manufactured by Ashland).

[0206] The other polymers may be used alone or two or more of them may be used in combination. With respect to 100 parts by mass of the polymer components contained in the liquid crystal aligning agent, the content ratio of the other polymers is preferably 10 to 90 parts by mass, more preferably 20 to 80 parts by mass.

[0207] It should be noted that in this specification, the polymer components refer to the general term of polymer (A), polymer (B), and other polymers other than these polymers contained in the liquid crystal aligning agent. When the polymers contained in the liquid crystal aligning agent are only polymer (A) and polymer (B), the polymer components refer to polymer (A) and polymer (B).

[0208] <Liquid crystal aligning agent>

[0209] The liquid crystal aligning agent of the present invention is used for preparing a liquid crystal alignment film, and from the viewpoint of forming a uniform thin film, it is usually in the form of a coating solution. In the liquid crystal aligning agent of the present invention, a coating solution containing the above-mentioned polymer components and a solvent is also preferred.

[0210] The content (concentration) of the polymer components contained in the liquid crystal aligning agent of the present invention can be appropriately changed according to the setting of the thickness of the coating film to be formed. From the aspect of forming a uniform and defect - free coating film, it is preferably 1% by mass or more with respect to the total amount of the liquid crystal aligning agent. From the aspect of the storage stability of the solution, it is preferably 10% by mass or less.

[0211] From the viewpoint of appropriately achieving the effects of the present disclosure, the total content ratio of polymer (A) and polymer (B) in the liquid crystal aligning agent is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, and further preferably 50 parts by mass or more, based on 100 parts by mass in total of the polymers contained in the liquid crystal aligning agent. When the liquid crystal aligning agent contains other polymers, the content ratio of polymer (A) and polymer (B) is preferably 10 to 90 parts by mass, more preferably 20 to 80 parts by mass, based on 100 parts by mass of the polymer components contained in the liquid crystal aligning agent.

[0212] The solvent contained in the liquid crystal aligning agent is not particularly limited as long as it can uniformly dissolve the polymer components. Specific examples thereof include: N,N-dimethylformamide, N,N-dimethylacetamide, N,N-dimethylpropanamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethyl sulfoxide, γ-butyrolactone, γ-valerolactone, 1,3-dimethyl-2-imidazolidinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, N-n-propyl-2-pyrrolidone, N-i-propyl-2-pyrrolidone, N-n-butyl-2-pyrrolidone, N-t-butyl-2-pyrrolidone, N-n-pentyl-2-pyrrolidone, N-(3-methoxypropyl)-2-pyrrolidone, N-(2-ethoxyethyl)-2-pyrrolidone, N-(4-methoxybutyl)-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone (these are collectively referred to as "good solvents"), etc. Among them, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, or γ-butyrolactone is preferred. The content of the good solvent is preferably 20 to 99% by mass, more preferably 20 to 90% by mass, and particularly preferably 30 to 80% by mass, based on the total amount of the solvents contained in the liquid crystal aligning agent.

[0213] In addition, the solvent contained in the liquid crystal aligning agent preferably uses a mixed solvent in which, in addition to the above solvents, a solvent (also referred to as a poor solvent) that improves the coating property and the surface smoothness of the coating film when coating the liquid crystal aligning agent is used in combination. Specific examples of the poor solvent used in combination are as described below, but are not limited thereto.

[0214] For example, the following can be listed: diisopropyl ether, diisobutyl ether, diisobutyl carbinol (2,6-dimethyl-4-heptanol), ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, 4-hydroxy-4-methyl-2-pentanone, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, 3-ethoxybutyl acetate, 1-methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, ethylene glycol monoacetate, ethylene glycol diacetate, propylene carbonate, ethylene carbonate, ethylene glycol monobutyl ether, ethylene glycol monoisoamyl ether, ethylene glycol monohexyl ether, propylene glycol monobutyl ether, 1-(2-butoxyethoxy)-2-propanol, 2-(2-butoxyethoxy)-1-propanol, propylene glycol monomethyl ether acetate, propylene glycol diacetate, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 2-(2-ethoxyethoxy)ethyl acetate, diethylene glycol diacetate, n-butyl acetate, propylene glycol monoethyl ether acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, butyl 3-methoxypropionate, n-butyl lactate, isoamyl lactate, diethylene glycol monoethyl ether, diisobutyl ketone (2,6-dimethyl-4-heptanone), etc. The content of the poor solvent is preferably 1 to 80% by mass, more preferably 10 to 80% by mass, and particularly preferably 20 to 70% by mass of the total solvents contained in the liquid crystal aligning agent. The type and content of the poor solvent are appropriately selected according to the coating device, coating conditions, coating environment, etc. of the liquid crystal aligning agent.

[0215] Among them, diisobutyl carbinol, propylene glycol monobutyl ether, propylene glycol diacetate, diethylene glycol diethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, or diisobutyl ketone is preferred.

[0216] As preferred combinations of solvents of the good solvent and the poor solvent, the following can be listed: N-methyl-2-pyrrolidone and ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone and γ-butyrolactone and ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone and γ-butyrolactone and propylene glycol monobutyl ether, N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether, N-methyl-2-pyrrolidone and γ-butyrolactone and 4-hydroxy-4-methyl-2-pentanone and diethylene glycol diethyl ether, N-methyl-2-pyrrolidone 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 diisobutyl carbinol, N-methyl-2-pyrrolidone and γ-butyrolactone and dipropylene glycol dimethyl ether, N-methyl-2-pyrrolidone and propylene glycol monobutyl ether and dipropylene glycol dimethyl ether, etc.

[0217] The liquid crystal aligning agent of the present invention may further contain components other than the polymer component and the solvent (hereinafter also referred to as additive components). Examples of such additive components include: compounds for enhancing the strength of the liquid crystal alignment film (hereinafter also referred to as crosslinkable compounds); adhesion aids for enhancing the adhesion between the liquid crystal alignment film and the substrate and between the liquid crystal alignment film and the sealant; dielectrics or conductive substances for adjusting the dielectric constant and resistance of the liquid crystal alignment film; or imidization accelerators for promoting imidization, etc.

[0218] Examples of the above crosslinkable compounds include at least one crosslinkable compound selected from the group consisting of a crosslinkable compound (c-1) having at least one substituent selected from epoxy group, oxetanyl group, oxazoline structure, cyclic carbonate group, blocked isocyanate group, hydroxyl group and alkoxy group, and a crosslinkable compound (c-2) having a polymerizable unsaturated group.

[0219] As preferred specific examples of the above crosslinkable compounds (c-1) and (c-2), the following compounds can be cited.As compounds having epoxy groups, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6 - hexanediol diglycidyl ether, glycerol diglycidyl ether, dibromoneopentyl glycol diglycidyl ether, 1,3,5,6 - tetraglycidyl - 2,4 - hexanediol, bisphenol A type epoxy resins such as EPIKOTE 828 (manufactured by Mitsubishi Chemical Corporation), bisphenol F type epoxy resins such as EPIKOTE 807 (manufactured by Mitsubishi Chemical Corporation), hydrogenated bisphenol A type epoxy resins such as YX - 8000 (manufactured by Mitsubishi Chemical Corporation), epoxy resins containing a biphenyl skeleton such as YX6954BH30 (manufactured by Mitsubishi Chemical Corporation), phenol novolak type epoxy resins such as EPPN - 201 (manufactured by Nippon Kayaku Co., Ltd.), (o, m, p -) cresol novolak type epoxy resins such as EOCN - 102S (manufactured by Nippon Kayaku Co., Ltd.), tetrakis (glycidyl oxymethyl) methane, N, N, N', N' - tetraglycidyl - 1,4 - phenylenediamine, N, N, N', N' - tetraglycidyl - 2,2' - dimethyl - 4,4' - diaminobiphenyl, 2,2 - bis [4 - (N, N - diglycidyl - 4 - aminophenoxy) phenyl] propane, compounds in which a tertiary nitrogen atom is bonded to an aromatic carbon atom such as N, N, N', N' - tetraglycidyl - 4,4' - diaminodiphenylmethane; N, N, N', N' - tetraglycidyl - 1,2 - diaminocyclohexane, N, N, N', N' - tetraglycidyl - 1,3 - diaminocyclohexane, N, N, N', N' - tetraglycidyl - 1,4 - diaminocyclohexane, bis (N, N - diglycidyl - 4 - aminocyclohexyl) methane, bis (N, N - diglycidyl - 2 - methyl - 4 - aminocyclohexyl) methane, bis (N, N - diglycidyl - 3 - methyl - 4 - aminocyclohexyl) methane, 1,3 - bis (N, N - diglycidylaminomethyl) cyclohexane, 1,4 - bis (N, N - diglycidylaminomethyl) cyclohexane, 1,3 - bis (N, N - diglycidylaminomethyl) benzene, 1,4 - bis (N, N - diglycidylaminomethyl) benzene, 1,3,5 - tris (N, N - diglycidylaminomethyl) cyclohexane, 1,3,5 - tris (N, N - diglycidylaminomethyl) benzene and other compounds in which a tertiary nitrogen atom is bonded to an aliphatic carbon atom, isocyanurate compounds such as triglycidyl isocyanurate such as TEPIC (manufactured by Nissan Chemical Industries, Ltd.), compounds described in paragraph 0037 of Japanese Patent Laid - Open No. 10 - 338880, compounds described in WO2017 / 170483, etc.

[0220] As compounds having an oxetanyl group, 1,4-bis{[(3-ethyl-3-oxetanyl)methoxy]methyl}benzene (ARON OXETANE OXT-121 (XDO)), bis[2-(3-oxetanyl)butyl] ether (ARON OXETANE OXT-221 (DOX)), 1,4-bis[(3-ethyloxetane-3-yl)methoxy]benzene (HQOX), 1,3-bis[(3-ethyloxetane-3-yl)methoxy]benzene (RSOX), 1,2-bis[(3-ethyloxetane-3-yl)methoxy]benzene (CTOX), compounds having two or more oxetanyl groups described in paragraphs 0170 to 0175 of WO2011 / 132751, and the like.

[0221] As compounds having an oxazoline structure, compounds such as 2,2'-bis(2-oxazoline) and 2,2'-bis(4-methyl-2-oxazoline); polymers and oligomers having an oxazoline group such as EPOCROS (trade name, manufactured by Nippon Shokubai Co., Ltd.); compounds described in paragraph 0115 of JP-A-2007-286597, and the like.

[0222] As compounds having a cyclic carbonate group, N,N,N',N'-tetrakis[(2-oxy-1,3-dioxolan-4-yl)methyl]-4,4'-diaminodiphenylmethane, N,N'-bis[(2-oxy-1,3-dioxolan-4-yl)methyl]-1,3-phenylenediamine, compounds described in paragraphs 0025 to 0030 and 0032 of WO2011 / 155577, and the like.

[0223] As compounds having a blocked isocyanate group, 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 two or more protected isocyanate groups described in paragraph 0046 to 0047 of JP-A-2014-224978; compounds having three or more protected isocyanate groups described in paragraphs 0119 to 0120 of WO2015 / 141598, and the like.

[0224] As compounds having a hydroxyl group and / or an alkoxy group, N,N,N',N'-tetrakis(2-hydroxyethyl) adipamide, 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl) propane, 2,2-bis(4-hydroxy-3,5-dimethoxyphenyl) propane, 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl)-1,1,1,3,3,3-hexafluoropropane, etc.; compounds described in paragraph 0058 of WO2015 / 072554, Japanese Patent Laid-Open No. 2016-118753; compounds described in Japanese Patent Laid-Open No. 2016-200798; compounds described in WO2010 / 074269, etc.

[0225] As crosslinkable compounds having a polymerizable unsaturated group, glycerol mono(meth)acrylate, glycerol di(meth)acrylate (1,2-, 1,3-type mixture), glycerol tri(meth)acrylate, 1,3-diglycerol acid glycerol di(meth)acrylate, pentaerythritol tri(meth)acrylate, diethylene glycol mono(meth)acrylate, triethylene glycol mono(meth)acrylate, tetraethylene glycol mono(meth)acrylate, pentaethylene glycol mono(meth)acrylate, hexaethylene glycol mono(meth)acrylate, etc.

[0226] The above compounds are an example of crosslinkable compounds and are not limited to these. For example, components other than those described above disclosed on pages 53, 0105 to 55, 0116 of WO2015 / 060357 can be cited. In addition, two or more crosslinkable compounds can also be combined.

[0227] When using a crosslinkable compound, the content of the crosslinkable compound in the liquid crystal aligning agent is preferably 0.5 to 20 parts by mass, more preferably 1 to 15 parts by mass, relative to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent.

[0228] Examples of the above adhesion aids include: 3 - aminopropyltrimethoxysilane, 3 - aminopropyltriethoxysilane, 3 - aminopropyldiethoxymethylsilane, 2 - aminopropyltrimethoxysilane, 2 - aminopropyltriethoxysilane, N-(2 - aminoethyl)-3 - aminopropyltrimethoxysilane, N-(2 - aminoethyl)-3 - aminopropylmethyldimethoxysilane, 3 - ureidopropyltrimethoxysilane, 3 - ureidopropyltriethoxysilane, N - ethoxycarbonyl - 3 - aminopropyltrimethoxysilane, N - ethoxycarbonyl - 3 - aminopropyltriethoxysilane, N - 3 - triethoxysilylpropyltriethylenetetramine, N - 3 - trimethoxysilylpropyltriethylenetetramine, 10 - trimethoxysilyl - 1,4,7 - triazadecane, 10 - triethoxysilyl - 1,4,7 - triazadecane, 9 - trimethoxysilyl - 3,6 - diaza - nonyl acetate, 9 - triethoxysilyl - 3,6 - diaza - nonyl acetate, N - benzyl - 3 - aminopropyltrimethoxysilane, N - benzyl - 3 - aminopropyltriethoxysilane, N - phenyl - 3 - aminopropyltrimethoxysilane, N - phenyl - 3 - aminopropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4 - epoxycyclohexyl)ethyltrimethoxysilane, 3 - glycidoxypropylmethyldimethoxysilane, 3 - glycidoxypropyltrimethoxysilane, 3 - glycidoxypropylmethyldiethoxysilane, 3 - glycidoxypropyltriethoxysilane, p - styryltrimethoxysilane, 3 - methacryloxypropylmethyldimethoxysilane, 3 - methacryloxypropyltrimethoxysilane, 3 - methacryloxypropylmethyldiethoxysilane, 3 - methacryloxypropyltriethoxysilane, 3 - acryloxypropyltrimethoxysilane, tris[3-(trimethoxysilyl)propyl]isocyanurate, 3 - mercaptopropylmethyldimethoxysilane, 3 - mercaptopropyltrimethoxysilane, 3 - isocyanatopropyltriethoxysilane and other silane coupling agents.

[0229] When using the adhesion aid, the content of the adhesion aid in the liquid crystal aligning agent is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, relative to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent.

[0230] Examples of the dielectric or conductive substance include monoamines having a nitrogen - containing aromatic heterocycle such as 3 - aminomethylpyridine.

[0231] When using the dielectric or conductive substance, the content of the dielectric or conductive substance in the liquid crystal aligning agent is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, relative to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent.

[0232] As a compound for promoting the above imidization, a compound preferably having a basic moiety (e.g., primary amino group, aliphatic heterocycle (e.g., pyrrolidine skeleton), aromatic heterocycle (e.g., imidazole ring, indole ring), or guanidyl group, etc.) (wherein, the above crosslinkable compound; a compound for adjusting the dielectric constant and resistance of the liquid crystal alignment film is excluded), or a compound that generates the above basic moiety during firing. More preferably, it is a compound that generates the above basic moiety during firing. If specific preferred examples are listed, there can be listed amino acids in which part or all of the basic moieties possessed by the amino acids are protected. As a protecting group for the basic moiety possessed by the above amino acids, there can be listed carbamate-based protecting groups such as Boc group. As specific examples of the above amino acids, there can be listed: glycine, alanine, cysteine, methionine, asparagine, glutamine, valine, leucine, phenylalanine, tyrosine, tryptophan, proline, hydroxyproline, arginine, histidine, lysine, ornithine. If more specific preferred examples of the compound for promoting imidization are listed, there can be listed N-α-(9-fluorenylmethoxycarbonyl)-N-τ-(tert-butoxycarbonyl)-L-histidine or (2S)-2-[(2-methylpropan-2-yl)oxycarbonylamino]-3-[1-[(2-methylpropan-2-yl)oxycarbonyl]imidazol-4-yl]propanoic acid (N-α-(tert-butoxycarbonyl)-N-τ-(tert-butoxycarbonyl)-L-histidine), etc.

[0233] With respect to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent, the content of the compound for promoting the above 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 further preferably 5 to 20 parts by mass.

[0234] (Liquid crystal alignment film)

[0235] The liquid crystal alignment film of the present invention is formed using the above liquid crystal aligning agent of the present invention.

[0236] The manufacturing method of the liquid crystal alignment film of the present invention includes, for example, irradiating polarized radiation to a film obtained by coating the above liquid crystal aligning agent on a substrate and firing.

[0237] As a preferred embodiment of the manufacturing method of the liquid crystal alignment film of the present invention, for example, there can be listed a manufacturing method of a liquid crystal alignment film including a step of coating the above liquid crystal aligning agent on a substrate (step (1)), a step of firing the coated liquid crystal aligning agent (step (2)), and a step of performing an alignment treatment on the film obtained in step (2) as needed (step (3)).

[0238] <Step (1)>

[0239] As the substrate coated with the liquid crystal aligning agent used in the present invention, there is no particular limitation as long as it is a substrate with high transparency, and plastic substrates such as glass substrates, silicon nitride substrates, acrylic substrates, polycarbonate substrates, etc. can also be used. At this time, from the aspect of simplifying the process, it is preferable to use a substrate formed with an ITO (Indium Tin Oxide) electrode or the like for driving liquid crystal. In addition, in a reflective liquid crystal display element, if it is only a single-sided substrate, an opaque material such as a silicon wafer can also be used, and in this case, a light-reflecting material such as aluminum can be used for the electrode. Furthermore, in the case of manufacturing a liquid crystal display element using the IPS driving method or the FFS driving method, a substrate provided with an electrode composed of a transparent conductive film or a metal film patterned in a comb shape and a counter substrate without an electrode are used.

[0240] As a method of coating and forming a liquid crystal aligning agent on a substrate, examples include screen printing, offset printing, flexographic printing, inkjet method, or spraying method, etc. Among them, the coating and forming method by the inkjet method can be preferably used.

[0241] The IPS substrate used as a comb-tooth electrode substrate in the IPS mode has a substrate, a plurality of linear electrodes formed on the substrate and arranged in a comb shape, and a liquid crystal alignment film formed on the substrate so as to cover the linear electrodes.

[0242] It should be noted that the FFS substrate used as a comb-tooth electrode substrate in the FFS mode has a substrate, a planar electrode formed on the substrate, an insulating film formed on the planar electrode, a plurality of linear electrodes formed on the insulating film and arranged in a comb shape, and a liquid crystal alignment film formed on the insulating film so as to cover the linear electrodes.

[0243] Figure 1 It is a schematic cross-sectional view showing an example of a transverse electric field liquid crystal display element in the IPS mode having a liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention.

[0244] In Figure 1 In the exemplified transverse electric field liquid crystal display element 1, liquid crystal 3 is sandwiched between a comb-tooth electrode substrate 2 having a liquid crystal alignment film 2c and a counter substrate 4 having a liquid crystal alignment film 4a. The comb-tooth electrode substrate 2 has: a substrate 2a, a plurality of linear electrodes 2b formed on the substrate 2a and arranged in a comb shape, and a liquid crystal alignment film 2c formed on the substrate 2a so as to cover the linear electrodes 2b. The counter substrate 4 has a substrate 4b and a liquid crystal alignment film 4a formed on the substrate 4b. The liquid crystal alignment film 2c is the liquid crystal alignment film of the present invention. The liquid crystal alignment film 4a is also the liquid crystal alignment film of the present invention.

[0245] In Figure 1In the transverse electric field liquid crystal display element 1, when a voltage is applied to the linear electrode 2b, an electric field is generated between the linear electrodes 2b as shown by the electric field lines L.

[0246] Figure 2 It is a schematic cross-sectional view showing an example of a fringe field switching (FFS) mode transverse electric field liquid crystal display element having a liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention.

[0247] In Figure 2 In the exemplified transverse electric field liquid crystal display element 1, a liquid crystal 3 is sandwiched between a comb-shaped electrode substrate 2 having a liquid crystal alignment film 2h and a counter substrate 4 having a liquid crystal alignment film 4a. The comb-shaped electrode substrate 2 has a base material 2d, a surface electrode 2e formed on the base material 2d, an insulating film 2f formed on the surface electrode 2e, a plurality of linear electrodes 2g formed on the insulating film 2f and arranged in a comb shape, and a liquid crystal alignment film 2h formed on the insulating film 2f so as to cover the linear electrodes 2g. The counter substrate 4 has a base material 4b and a liquid crystal alignment film 4a formed on the base material 4b. The liquid crystal alignment film 2h is the liquid crystal alignment film of the present invention. The liquid crystal alignment film 4a is also the liquid crystal alignment film of the present invention.

[0248] In Figure 2 In the transverse electric field liquid crystal display element 1, when a voltage is applied to the surface electrode 2e and the linear electrodes 2g, an electric field is generated between the surface electrode 2e and the linear electrodes 2g as shown by the electric field lines L.

[0249] <Process (2)>

[0250] Process (2) is a process of firing the liquid crystal aligning agent coated on a substrate to form a film. After coating the liquid crystal aligning agent on the substrate, a heating unit such as a hot plate, a hot air circulation type oven or an IR (Infrared Ray) type oven can be used to evaporate the above solvent or perform thermal imidization of polyamic acid or polyamic acid ester in the polymer. The drying and firing processes after coating the liquid crystal aligning agent of the present invention can be carried out at any temperature and time, and can also be carried out multiple times. The temperature for evaporating the solvent of the liquid crystal aligning agent, as the temperature of the heating unit, can be carried out, for example, at 40 to 180 °C, but from the viewpoint of shortening the process, it can be carried out at 40 to 150 °C. The firing time is not particularly limited, for example, it is 1 to 10 minutes, preferably 1 to 5 minutes. In the case of further performing a process of thermal imidization of polyamic acid in the polymer on the process of evaporating the above solvent, after the process of evaporating the above solvent, as the temperature of the heating unit, a firing process can be additionally carried out, for example, in a temperature range of 150 to 300 °C, preferably 150 to 250 °C. The firing time in the thermal imidization process is not particularly limited, for example, it is 5 to 40 minutes, preferably 5 to 30 minutes.

[0251] If the fired film is too thin, the reliability of the liquid crystal display element may sometimes decrease. Therefore, it is preferably 5 to 300 nm, more preferably 10 to 200 nm.

[0252] <Process (3)>

[0253] Process (3) is a process of performing an alignment treatment on the film obtained in process (2). As a method for aligning a liquid crystal alignment film, a rubbing treatment method or a photo-alignment treatment method can be cited, and the photo-alignment treatment method is preferred. As the photo-alignment treatment method, the following methods can be cited: irradiating the surface of the above-mentioned film with radiation polarized in a certain direction, and performing a heat treatment as appropriate to impart liquid crystal alignment properties (also referred to as 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 preferred, and ultraviolet rays having a wavelength of 200 to 400 nm are more preferred.

[0254] The irradiation amount of the above-mentioned radiation is preferably 1 to 10000 mJ / cm 2 and more preferably 100 to 5000 mJ / cm 2 .

[0255] As a light source for irradiating light, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, a Deep UV lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, a mercury-xenon lamp, an excimer laser (for example, a KrF excimer laser), a fluorescent lamp, an LED lamp, a halogen lamp (for example, a sodium lamp), a microwave-excited electrodeless lamp, etc. can be used.

[0256] In addition, in the case of using polarized light as the irradiated light, the higher the extinction ratio of the polarized light, the higher the anisotropy that can be imparted. Therefore, for example, in the case of ultraviolet rays, the extinction ratio of polarized ultraviolet rays is more preferably 10:1 or more, and further preferably 20:1 or more.

[0257] In addition, in the case of irradiating radiation, in order to improve the liquid crystal alignment properties, it is also possible to irradiate the radiation while heating the substrate having the above-mentioned film at 50 to 250 °C. The liquid crystal alignment film produced as described above can make the liquid crystal molecules stably align in a fixed direction.

[0258] Furthermore, in the above method, for the liquid crystal alignment film irradiated with polarized radiation, it is also possible to perform a contact treatment on it with a solvent or perform a heat treatment on the liquid crystal alignment film irradiated with radiation.

[0259] As the solvent used in the above contact treatment, there is no particular limitation as long as it is a solvent capable of dissolving the decomposition products generated from the film-like substance by irradiation with radiation. Specific examples include: water, methanol, ethanol, 2-propanol, acetone, methyl ethyl ketone, 1-methoxy-2-propanol, 1-methoxy-2-propyl acetate, butyl cellosolve, ethyl lactate, methyl lactate, diacetone alcohol, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propyl acetate, butyl acetate, cyclohexyl acetate, etc. Among them, from the aspects of generality and solvent safety, water, 2-propanol, 1-methoxy-2-propanol or ethyl lactate are preferred. Water, 1-methoxy-2-propanol or ethyl lactate are more preferred. The solvent can be one kind or a combination of two or more kinds.

[0260] As the method of the above contact treatment, dip treatment and spray treatment (also called spraying treatment) can be cited. From the aspect of efficiently dissolving the decomposition products generated from the film-like substance by irradiation with radiation, the treatment time in these treatments is preferably 10 seconds to 1 hour. Among them, dip treatment for 1 minute to 30 minutes is preferred. In addition, the solvent during the above contact treatment can be at room temperature or heated, preferably 10 to 80 °C, more preferably 20 to 50 °C. In addition, from the aspect of the solubility of the decomposition products, ultrasonic treatment or the like can be carried out as needed.

[0261] After the above contact treatment, rinsing (also called flushing) and firing using low-boiling solvents such as water, methanol, ethanol, 2-propanol, acetone, methyl ethyl ketone, etc. are preferably carried out. At this time, either rinsing or firing can be carried out or both can be carried out. The firing temperature is preferably 150 to 300 °C, more preferably 180 to 250 °C, and particularly preferably 200 to 230 °C. In addition, the firing time is preferably 10 seconds to 30 minutes, preferably 1 to 10 minutes.

[0262] The heat treatment of the above-mentioned radiation-irradiated coating film is preferably carried out at 50 to 300 °C for 1 minute to 30 minutes, and more preferably carried out at 120 to 250 °C for 1 minute to 30 minutes.

[0263] (Liquid crystal display element)

[0264] The liquid crystal display element of the present invention has the liquid crystal alignment film of the present invention.

[0265] From the viewpoint of obtaining high liquid crystal alignment, the liquid crystal alignment film of the present invention is preferably useful as the liquid crystal alignment film of a liquid crystal display element of a horizontal electric field mode such as the IPS mode or the FFS mode, particularly as the liquid crystal alignment film of a liquid crystal display element of the FFS mode.

[0266] A liquid crystal display device can be manufactured by preparing a substrate with a liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention and then fabricating a liquid crystal cell by a known method, and disposing a liquid crystal in the liquid crystal cell. Specifically, the following two methods can be cited.

[0267] In the first method, first, two substrates are disposed opposite to each other with a gap (cell gap) therebetween such that the respective liquid crystal alignment films face each other. Next, the peripheral portions of the two substrates are bonded using a sealant, and a liquid crystal composition is injected and filled into the cell gap defined by the substrate surfaces and the sealant. After contacting the film surface, the injection hole is sealed.

[0268] In addition, the second method is a method called the ODF (One Drop Fill) method. On a predetermined site on one of the two substrates on which a liquid crystal alignment film is formed, for example, an ultraviolet curable sealant is coated, and a liquid crystal composition is further dropped at several predetermined locations on the liquid crystal alignment film surface. Then, it is bonded to the other substrate with the liquid crystal alignment films facing each other, and the liquid crystal composition is pushed to the entire surface of the substrate to contact the film surface. Next, ultraviolet light is irradiated onto the entire surface of the substrate to cure the sealant.

[0269] Regardless of which of the first method and the second method is used, it is desirable to further heat to a temperature at which the liquid crystal composition used becomes isotropic and then slowly cool to room temperature, thereby removing the flow alignment during liquid crystal filling.

[0270] It should be noted that in the case where a rubbing alignment treatment is performed on the coating film, the two substrates are disposed opposite to each other such that the rubbing directions of the respective coating films form a predetermined angle, for example, orthogonal or antiparallel. Similarly, in the case where a photo-alignment treatment is performed, they are disposed opposite to each other such that the alignment directions form a predetermined angle, for example, orthogonal or antiparallel.

[0271] As the sealant, for example, an epoxy resin containing a curing agent and alumina balls as spacers can be used. As the liquid crystal, nematic liquid crystals and smectic liquid crystals can be cited, and among them, nematic liquid crystals are preferred.

[0272] The liquid crystal composition is not particularly limited, and a composition containing at least one liquid crystal compound (liquid crystal molecule) can be cited. Either a liquid crystal composition with a positive dielectric anisotropy (positive liquid crystal composition, also called positive type liquid crystal) or a liquid crystal composition with a negative dielectric anisotropy (negative liquid crystal composition, also called negative type liquid crystal) can be used, and a negative liquid crystal material is preferred.

[0273] The above liquid crystal composition may contain liquid crystal compounds having a fluorine atom, a hydroxyl group, an amino group, a fluorine atom-containing group (e.g., trifluoromethyl), a cyano group, an alkyl group, an alkoxy group, an alkenyl group, an isothiocyanate group, a heterocycle, a cycloalkane, a cycloalkene, a steroid skeleton, a benzene ring, or a naphthalene ring, or may contain a compound having two or more rigid moieties (mesogenic skeletons) exhibiting liquid crystallinity in the molecule (e.g., a bis-mesogenic compound in which two rigid biphenyl structures or terphenyl structures are linked by an alkyl group, etc.). The liquid crystal composition may be a nematic liquid crystal composition, a smectic liquid crystal composition, or a cholesteric liquid crystal composition.

[0274] In addition, from the viewpoint of improving liquid crystal alignment, the above liquid crystal composition may further contain additives. Such additives include: photopolymerizable monomers such as compounds having the following polymerizable groups, optically active compounds (e.g., S-811 manufactured by Merck & Co., Inc.), antioxidants, ultraviolet absorbers, pigments, defoamers, polymerization initiators, or polymerization inhibitors, etc.

[0275] Examples of positive liquid crystals include ZLI-2293, ZLI-4792, MLC-2003, MLC-2041, MLC-3019, or MLC-7081 manufactured by Merck & Co., Inc.

[0276] Examples of negative liquid crystals include MLC-6608, MLC-6609, MLC-6610, MLC-6882, MLC-6886, MLC-7026, MLC-7026-000, MLC-7026-100, or MLC-7029 manufactured by Merck & Co., Inc.

[0277] In addition, in the PSA (Polymer Sustained Alignment) mode, examples of liquid crystals containing compounds having a polymerizable group include MLC-3023 manufactured by Merck & Co., Inc.

[0278] Next, the polarizers are set. Specifically, a pair of polarizers are pasted on the surfaces of the two substrates on the side opposite to the liquid crystal layer. Examples of polarizers include: a polarizer formed by sandwiching a polarizing film called an "H film" with a cellulose acetate protective film; or a polarizer composed of the H film itself, which is formed by stretching and orienting polyvinyl alcohol while absorbing iodine.

[0279] [Examples]

[0280] Hereinafter, examples are listed to further illustrate the present invention in detail, but the present invention is not limited thereto. The abbreviations of the compounds used and the measurement methods of each property are as follows.

[0281] (Solvent)

[0282] NMP: N-methyl-2-pyrrolidone

[0283] BCS: Butyl Cellosolve

[0284] (Tetracarboxylic dianhydride)

[0285] (ADA-1) to (ADA-3): Compounds represented by the following formulas (ADA-1) to (ADA-3) respectively

[0286]

[0287] (Diamine)

[0288] (DA-1) to (DA-8): Compounds represented by the following formulas (DA-1) to (DA-8) respectively

[0289]

[0290] (Terminal modifier)

[0291] SA: Succinic anhydride

[0292] (Additive)

[0293] AD-1: Compound represented by the following formula (AD-1)

[0294] AD-2: (2S)-2-[(2-methylpropan-2-yl)oxycarbonylamino]-3-[1-[(2-methylpropan-2-yl)oxycarbonyl]imidazol-4-yl]propanoic acid (compound represented by the following formula (AD-2))

[0295] AD-3: 3-Glycidoxypropylmethyldiethoxysilane (compound represented by the following formula (AD-3))

[0296]

[0297] [Measurement of viscosity]

[0298] In the synthesis example, 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 volume of 1.1 mL, a conical rotor TE-1 (1°34', R24), and a temperature of 25°C

[0299] (Synthesis of polymer)

[0300] <Synthesis example 1>

[0301] In a 500 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, DA-1 (1.35 g, 12.5 mmol), DA-2 (1.73 g, 7.50 mmol), and DA-3 (1.49 g, 5.0 mmol) were added, and then 41.1 g of NMP was added. While introducing nitrogen, it was stirred to dissolve. The four-necked flask containing this diamine solution was cooled in a water bath, and then, while stirring, ADA-3 (1.88 g, 7.5 mmol) was added, and then 16.9 g of NMP was added. It was stirred for 2 hours while heating to 50 °C. Then, after cooling in a water bath, ADA-2 (4.93 g, 16.8 mmol) was added, and then 25.4 g of NMP was added to make the solid component concentration reach 12% by mass, and it was stirred at 70 °C for 2 hours. Then, it was cooled to room temperature, and thus a polyamic acid solution (PAA-1) was obtained. The viscosity of this polyamic acid was 330 mPa·s.

[0302] <Synthesis Example 2>

[0303] In a 100 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, DA-1 (0.54 g, 5.0 mmol), DA-4 (1.99 g, 5.0 mmol), DA-5 (1.83 g, 7.5 mmol), and DA-6 (2.40 g, 3.75 mmol) were taken, and 77.8 g of NMP was added. While introducing nitrogen, it was stirred to dissolve. While stirring this diamine solution, ADA-1 (5.32 g, 24.0 mmol) was added, and then 10.8 g of NMP was added to make the solid component concentration reach 12% by mass, and it was stirred at 40 °C for 20 hours, and thus a polyamic acid solution A-1 was obtained.

[0304] Next, 30 g of the polyamic acid solution A-1 obtained in a 100 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube was taken out, SA (0.05 g, 0.5 mmol) was added, and it was stirred at room temperature for 24 hours to obtain a polyamic acid solution (PAA-2) containing a non-amino terminal structure. The viscosity of this polyamic acid solution was 198 mPa·s.

[0305] <Synthesis Example 3>

[0306] In a 200 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, DA-7 (6.38 g, 32.0 mmol) and DA-8 (1.22 g, 8.0 mmol) were taken, and 110.1 g of NMP was added. While introducing nitrogen, it was stirred to dissolve. While stirring this diamine solution, ADA-2 (11.18 g, 38.0 mmol) was added, and then 27.5 g of NMP was added to make the solid component concentration reach 12% by mass, and it was stirred at 25 °C for 24 hours to obtain a polyamic acid solution (PAA-3). The viscosity of this polyamic acid was 398 mPa·s.

[0307] <Synthesis Example 4>

[0308] In a 100 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, DA-1 (0.54 g, 5.0 mmol), DA-4 (1.99 g, 5.0 mmol), DA-5 (1.83 g, 7.5 mmol), and DA-6 (2.40 g, 3.75 mmol) were taken, and 77.8 g of NMP was added. While introducing nitrogen, the mixture was stirred to dissolve it. While stirring this diamine solution, ADA-1 (5.32 g, 24.0 mmol) was added, and then 10.8 g of NMP was further added to make the solid component concentration reach 12% by mass. The mixture was stirred at 40 °C for 20 hours, and thus a polyamic acid solution (PAA-4) was obtained. The viscosity of this polyamic acid solution was 199 mPa·s.

[0309] <Synthesis Example 5>

[0310] In a 300 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, DA-1 (1.08 g, 10.0 mmol) and DA-2 (3.45 g, 15.0 mmol) were added, and then 40.82 g of NMP was added. While introducing nitrogen, the mixture was stirred to dissolve it. The four-necked flask containing this diamine solution was cooled in a water bath, and while stirring, ADA-3 (1.88 g, 7.5 mmol) was added, and then 16.9 g of NMP was added. The temperature was raised to 50 °C and stirred for 2 hours. Then, after cooling in the water bath, ADA-2 (4.78 g, 16.2 mmol) was added, and then 24.4 g of NMP was added to make the solid component concentration reach 12% by mass. The mixture was stirred at 70 °C for 2 hours. Then, it was cooled to room temperature, and thus a polyamic acid solution (PAA-5) was obtained. The viscosity of this polyamic acid was 332 mPa·s.

[0311] <Synthesis Example 6>

[0312] In a 300 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, DA-2 (3.45 g, 15.0 mmol) and DA-3 (2.98 g, 10.0 mmol) were added, and then 44.08 g of NMP was added. While introducing nitrogen, the mixture was stirred to dissolve it. The four-necked flask containing this diamine solution was cooled in a water bath, and while stirring, ADA-3 (1.88 g, 7.5 mmol) was added, and then 17.23 g of NMP was added. The temperature was raised to 50 °C and stirred for 2 hours. Then, after cooling in the water bath, ADA-2 (4.81 g, 16.3 mmol) was added, and then 35.33 g of NMP was added to make the solid component concentration reach 12% by mass. The mixture was stirred at 70 °C for 2 hours. Then, it was cooled to room temperature, and thus a polyamic acid solution (PAA-6) was obtained. The viscosity of this polyamic acid was 340 mPa·s.

[0313] The specifications of the polyamic acid obtained in the above synthesis examples are shown in Table 1. In the table, the values in parentheses for the tetracarboxylic acid component represent the amounts (mole parts) of each tetracarboxylic dianhydride used relative to 100 mole parts of the total amount of the tetracarboxylic acid component used in the polymerization. The values in parentheses for the diamine component represent the amounts (mole parts) of each diamine used relative to 100 mole parts of the total amount of the diamine component used in the polymerization.

[0314] [Table 1]

[0315]

[0316] (Preparation of Liquid Crystal Alignment Agent)

[0317] <Example 1>

[0318] In a 50 mL Erlenmeyer flask containing a magnetic stir bar, 4.77 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1, 3.18 g of the polyamic acid solution (PAA-2) obtained in Synthesis Example 2, 0.32 g of a 3.0 mass% NMP solution of additive AD-3, 0.48 g of a 10 mass% NMP solution of AD-1, 3.78 g of NMP, and 5.40 g of BCS were added. Further, 0.076 g of additive AD-2 was added, and the mixture was stirred with a magnetic stirrer for 1 hour to obtain a 5.3 mass% liquid crystal alignment agent (AL-1).

[0319] (Preparation of Liquid Crystal Alignment Agent)

[0320] <Example 2>

[0321] In a 50 mL Erlenmeyer flask containing a magnetic stir bar, 3.98 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1, 3.98 g of the polyamic acid solution (PAA-2) obtained in Synthesis Example 2, 0.32 g of a 3.0 mass% NMP solution of additive AD-3, 0.48 g of a 10 mass% NMP solution of AD-1, 3.78 g of NMP, and 5.40 g of BCS were added. Further, 0.076 g of additive AD-2 was added, and the mixture was stirred with a magnetic stirrer for 1 hour to obtain a 5.3 mass% liquid crystal alignment agent (AL-2).

[0322] <Comparative Example 1>

[0323] In a 50 mL Erlenmeyer flask containing a magnetic stir bar, add 2.17 g of the polyamic acid solution (PAA-3) obtained in Synthesis Example 3, 2.17 g of the polyamic acid solution (PAA-4) obtained in Synthesis Example 4, 0.17 g of a 3.0 mass% NMP solution of additive AD-3, 0.26 g of a 10 mass% NMP solution of AD-1, 2.19 g of NMP, and 3.00 g of BCS. Then add 0.043 g of additive AD-2 and stir with a magnetic stirrer for 1 hour to obtain a 5.2 mass% liquid crystal aligning agent (AL-3).

[0324] <Comparative Example 2>

[0325] In a 50 mL Erlenmeyer flask containing a magnetic stir bar, add 4.77 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1, 3.18 g of the polyamic acid solution (PAA-4) obtained in Synthesis Example 4, 0.32 g of a 3.0 mass% NMP solution of additive AD-3, 0.48 g of a 10 mass% NMP solution of AD-1, 3.78 g of NMP, and 5.40 g of BCS. Then add 0.076 g of additive AD-2 and stir with a magnetic stirrer for 1 hour to obtain a 5.2 mass% liquid crystal aligning agent (AL-4).

[0326] <Comparative Example 3>

[0327] In a 50 mL Erlenmeyer flask containing a magnetic stir bar, add 4.42 g of the polyamic acid solution (PAA-2) obtained in Synthesis Example 2, 4.42 g of the polyamic acid solution (PAA-5) obtained in Synthesis Example 5, 0.35 g of a 3.0 mass% NMP solution of additive AD-3, 0.53 g of a 10 mass% NMP solution of AD-1, 4.28 g of NMP, and 6.0 g of BCS, and stir with a magnetic stirrer for 1 hour to obtain a 5.3 mass% liquid crystal aligning agent (AL-5).

[0328] <Comparative Example 4>

[0329] In a 50 mL Erlenmeyer flask containing a magnetic stir bar, add 3.18 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1, 4.77 g of the polyamic acid solution (PAA-6) obtained in Synthesis Example 6, 0.32 g of a 3.0 mass% NMP solution of additive AD-3, 0.48 g of a 10 mass% NMP solution of AD-1, 3.86 g of NMP, and 5.40 g of BCS, and stir with a magnetic stirrer for 1 hour to obtain a 5.3 mass% liquid crystal aligning agent (AL-6).

[0330] The specifications of the liquid crystal aligning agents obtained in the above-mentioned examples and comparative examples are shown in Table 2. In Table 2, the values in parentheses in the polyamic acid solution represent the amounts (parts by mass) of the respective polyamic acid solid components relative to a total of 100 parts by mass of the polyamic acid solid components. The values in the additives represent the amounts (parts by mass) of the respective additives relative to a total of 100 parts by mass of the polyamic acid solid components.

[0331] [Table 2]

[0332]

[0333] [Fabrication of a liquid crystal cell with FFS driving mode (photo-alignment treatment)]

[0334] (Examples 3, 4 and Comparative Examples 5 to 8)

[0335] A liquid crystal cell (hereinafter, FFS liquid crystal cell) having a configuration of a liquid crystal display element with FFS driving mode is fabricated.

[0336] First, a substrate with electrodes is prepared. A glass substrate with a size of 30 mm × 50 mm and a thickness of 0.7 mm is used. On the substrate, as the first layer, an ITO electrode having a pattern covering the entire surface and constituting the counter electrode is formed. On the counter electrode of the first layer, as the second layer, a SiN (silicon nitride) film formed by CVD method is formed. The SiN film of the second layer is a film with a thickness of 500 nm that functions as an interlayer insulating film. On the SiN film of the second layer, as the third layer, comb-shaped pixel electrodes formed by patterning an ITO film are arranged to form two pixels, a first pixel and a second pixel. The size of each pixel is 10 mm in length and about 5 mm in width. At this time, the counter electrode of the first layer and the pixel electrodes of the third layer are electrically insulated by the SiN film of the second layer.

[0337] The pixel electrodes of the third layer have a comb shape in which electrode elements with a width of 3 μm bent at an inner angle of 160° within the central portion are arranged in parallel at intervals of 6 μm, and one pixel has a first region and a second region with a line connecting the bent portions of the plurality of electrode elements as a boundary.

[0338] If the first region and the second region of each pixel are compared, the forming directions of the electrode elements of the pixel electrodes constituting them are different. That is, in the case where the direction connecting the bent portions of the plurality of electrode elements is taken as a reference, in the first region of the pixel, the electrode elements of the pixel electrode are formed at an angle of 80° in the clockwise direction, and in the second region of the pixel, the electrode elements of the pixel electrode are formed at an angle of 80° in the counterclockwise direction. That is, in the first region and the second region of each pixel, the directions of the in-plane switching (IPS: in-plane switching) of the liquid crystal molecules induced by the voltage application between the pixel electrode and the counter electrode are configured to be opposite to each other.

[0339] Next, the liquid crystal aligning agents AL-1 to AL-2 obtained in Examples 1 and 2 of the liquid crystal aligning agent and the liquid crystal aligning agents AL-3 to AL-6 obtained in Comparative Examples 1 to 4 were filtered with a 1.0 μm filter, and then spin-coated and applied to the above-mentioned electrode-bearing substrate and a glass substrate having a columnar spacer with a height of 4 μm and an ITO film formed on the back surface, respectively. After drying it on a hot plate at 80 °C for 5 minutes, it was fired in a hot air circulation oven at 230 °C for 30 minutes to form a coating film with a film thickness of 100 nm. Next, a photo-alignment treatment was performed. Specifically, ultraviolet rays with a wavelength of 254 nm and linearly polarized light with an extinction ratio of 10:1 or more were irradiated to the coating film surface through a polarizer. It should be noted that the irradiation dose of the irradiated ultraviolet rays was 400 mJ / cm 2 was carried out. Next, a heating step of heating the above-mentioned substrate with the coating film on a hot plate at 230 °C for 30 minutes was performed to obtain a substrate with a liquid crystal alignment film.

[0340] Two pieces of the above-mentioned substrates with liquid crystal alignment films were prepared, and a sealant (XN-1500T manufactured by Mitsui Chemicals, Inc.) was printed around them except for the liquid crystal injection port, and they were bonded with the liquid crystal alignment film surfaces facing each other and the alignment direction being 0°. Then, a heat treatment was performed at 120 °C for 90 minutes to cure the sealant, and an empty cell was fabricated. At room temperature, a positive liquid crystal MLC-3019 (manufactured by Merck & Co., Inc.) was vacuum-injected into the empty cell, and then the injection port was sealed to fabricate an FFS liquid crystal cell with reverse parallel alignment. The obtained FFS liquid crystal cell was heated at 120 °C for 1 hour and then left at 23 °C overnight for the following evaluations.

[0341] [Evaluation of in-plane uniformity]

[0342] The twist angle non-uniformity of the liquid crystal cell was evaluated using AxoStep manufactured by AXOMETRICS. The liquid crystal cell fabricated above was placed on the measurement stage, and the distribution of circular retardance within the pixel plane was measured without applying voltage, and 3σ, which is three times the standard deviation σ, was calculated. It can be said that the smaller the value of 3σ, the better the in-plane uniformity.

[0343] [Flicker characteristic evaluation]

[0344] Using two polarizers, the FFS liquid crystal cell fabricated above was set in an orthogonal Nicol state, and while irradiating with an LED backlight with a brightness of 10000 cd / m 2 , an AC voltage of 30 Hz and ±2.9 V was applied to the first pixel. The flicker at this time was measured using a display color analyzer (model: CA-410 manufactured by Konica Minolta), and a DC voltage was applied in such a way that the flicker value was minimized in the state where the AC voltage was applied. Then, the flicker after driving for 120 minutes was measured again in the state where the AC voltage and DC voltage were applied for 120 minutes. The unit of flicker is dB (decibel). It can be said that the smaller the value, the better the flicker characteristic.

[0345] As described above, the in-plane uniformity evaluation and flicker characteristic evaluation are shown in Table 3 below. It should be noted that the flicker characteristics of the liquid crystal aligning agents AL-3 to AL-6 were not evaluated.

[0346] [Table 3]

[0347]

[0348] <Total light transmittance evaluation>

[0349] <Example 5>

[0350] Using the liquid crystal aligning agent AL-1 obtained in Example 1, spin coating was performed on the ITO-coated glass substrate by rotating at 300 rpm for 5 seconds and then at 3300 ± 200 rpm for 30 seconds. Then, it was dried on a hot plate at 80°C for 5 minutes, and then fired in a hot air circulation oven at 230°C for 30 minutes to fabricate a coated substrate (AL-1-F) with a film formation thickness (set film thickness) of 100 nm.

[0351] <Example 6>

[0352] Using the liquid crystal aligning agent AL-2 obtained in Example 2, spin coating was carried out on a glass substrate with ITO at 300 rpm for 5 seconds and then at 3300 ± 200 rpm for 30 seconds. Then, it was dried on a hot plate at 80°C for 5 minutes, and then fired in a hot air circulation oven at 230°C for 30 minutes to fabricate a coated substrate (AL-2-F) with a film formation thickness (set film thickness) of 100 nm.

[0353] <Comparative Examples 9 - 12>

[0354] Using AL-3 - 6 obtained in Comparative Examples 2 - 5, coated substrates (AL-3-F to AL-6-F) were fabricated on a glass substrate with ITO in the same manner as in Example 5.

[0355] The total light transmittance of the coated substrates fabricated in Examples 5 and 6 and Comparative Examples 9 - 12 was measured using a haze meter (manufactured by Suga Test Co., Ltd., model: Haze Meter HZ-V3). The results are shown in Table 4. It can be said that the larger the value, the higher the transmittance of the film.

[0356] [Table 4]

[0357]

[0358] As can be seen from Tables 3 and 4, for the liquid crystal aligning agent using polyamic acid with diamines DA-1, DA-2, and DA-3 as diamine components and obtained from specific tetracarboxylic dianhydrides, a liquid crystal alignment film with good in-plane uniformity of alignment, excellent flicker characteristics, and high transmittance can be obtained.

[0359] Industrial Applicability

[0360] By using the liquid crystal aligning agent of the present invention, a liquid crystal alignment film with reduced deviation of the twist angle of the liquid crystal, suppression of flicker occurrence, and high transmittance can be obtained. Therefore, a liquid crystal display element with high display quality can be obtained. These elements are useful in liquid crystal displays for display purposes, dimming windows for controlling light transmission and blocking, light shutters, etc.

[0361] The liquid crystal display element of the present invention can be effectively applied to devices with various functions. For example, it can be used in liquid crystal TVs, clocks, portable game consoles, word processors, laptop computers, car navigation systems, camcorders, PDAs (Personal Digital Assistants), digital cameras, mobile phones, smartphones, various monitors, information displays, etc.

[0362] Explanation of Reference Numerals

[0363] 1: Horizontal electric field liquid crystal display element; 2: Comb electrode substrate; 2a: Substrate; 2b: Linear electrode; 2c: Liquid crystal alignment film; 2d: Substrate; 2e: Surface electrode; 2f: Insulating film; 2g: Linear electrode; 2h: Liquid crystal alignment film; 3: Liquid crystal; 4: Opposite substrate; 4a: Liquid crystal alignment film; 4b: Substrate; L: Electric field line.

Claims

1. A liquid crystal alignment agent, characterized in that: Containing the following polymer A and polymer B, Polymer A: polyamic acid A having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, As a structural unit derived from a tetracarboxylic acid derivative, the following formula (1T a ) shown in the structural unit a-1Ta, As a structural unit derived from diamine, it contains the following formula (1D a ) shown in the structural unit a-1Da, At least a portion of the ends of the polyamic acid A contain a non-amino group, and the non-amino group is a functional group represented by the following structural formula (E): Polymer B: polyamic acid B having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, As a structural unit derived from a tetracarboxylic acid derivative, the following formula (1T b ) shown in the structural unit b-1Tb, As a structural unit derived from diamine, it contains the following formula (1D b1 ) represented by the structural unit b-1Db1, the following formula (1D b2 ) shown in the structural unit b-1Db2, and "-N(Z)-Y U -N(Z)-" structural unit b-1Db3, Y U represents a divalent organic group having a urea bond, Z and the following formula (1D a ) is defined the same as Z, Where, X a represents a tetravalent organic group represented by the following formula (x-1), formula (1D a ), Ya represents a divalent organic group derived from diamine, and Z each independently represents a hydrogen atom or a monovalent organic group, In formula (x-1), R1 to R4 each independently represent 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, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 6 carbon atoms, an alkyloxycarbonyl group having 2 to 6 carbon atoms, or a phenyl group, at least one of R1 to R4 represents a group other than a hydrogen atom as defined above, and * represents a bond. In formula (E), Q is a monovalent organic group selected from the following groups e1 to e2, * represents a bonding bond, e1: a non-cyclic hydrocarbon group having 1 to 6 carbon atoms; e2: a monovalent organic group having 1 to 2 carboxyl groups and 2 to 30 carbon atoms, wherein the monovalent organic group does not contain an anhydride group, Where, X b represents a tetravalent organic group derived from an aromatic tetracarboxylic dianhydride, or a tetravalent organic group T having an alicyclic structure of five or more members 5a , Formula (1D b1 )~(1D b2 ), Z and the above formula (1D a ) is defined the same as Z, formula (1D b1 )~(1D b2 ) wherein any hydrogen atom on the benzene ring is optionally substituted by a monovalent group.

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

3. The liquid crystal aligning agent according to claim 1, wherein The e2 is a monovalent organic group having a residue derived from a dicarboxylic anhydride and having 1 to 2 carboxyl groups, wherein the monovalent organic group does not contain an acid anhydride group, and the e2 is selected from a compound e2-1 in which the dicarboxylic anhydride does not have an alkoxysilane structure or a compound e2-2 in which the dicarboxylic anhydride has an alkoxysilane structure.

4. The liquid crystal aligning agent according to claim 3, wherein The compound e2-1 is an aromatic cyclic dicarboxylic acid anhydride or an aliphatic cyclic dicarboxylic acid anhydride. The liquid crystal aligning agent according to claim 3 , wherein: The compound e2-2 is prepared from 4-(3-trimethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-triethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-trimethoxysilylpropyl)phthalic anhydride, 4-(3-triethoxysilylpropyl)phthalic anhydride, alkoxy-dimethylsilyl-alkyl succinic anhydride with 1 to 6 carbon atoms, di-alkoxy-methylsilyl-alkyl succinic anhydride with 1 to 6 carbon atoms, and 1-2-alkyl succinic anhydride. Alkyl-C2-8 alkyl succinic anhydride, tri-C1-6 alkoxy-silyl-C2-8 alkyl succinic anhydride, 4-(3-dimethylmethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-dimethylethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-dimethylmethoxysilylpropyl)phthalic anhydride, or 4-(3-dimethylethoxysilylpropyl)phthalic anhydride. The liquid crystal alignment agent according to claim 1 , wherein: The formula (x-1) is selected from the group consisting of the following formulas (x1-1) to (x1-5), * indicates a bonding key.

7. The liquid crystal aligning agent according to claim 1 or 2, wherein The structural unit a-1Da is derived from diamine 0"H-N(Z)-Ar1-L1-A-L 1’ -Ar 1’ -N(Z)-H" structural unit 1D-1, or a structural unit 1D-2 derived from a diamine other than the diamine 0, Ar1、Ar 1’ Each independently represents a benzene ring, a biphenyl structure or a naphthalene ring, Ar1, Ar 1’ Any hydrogen atom on the ring is optionally substituted by a monovalent group, A represents a divalent organic group having 1 to 10 carbon atoms and an alkylene structure, L1, L 1’ Each independently represents a single bond, -O-, -S-, -C(=O)-, -O-C(=O)-, -C(=O)-NR-, or -NR-C(=O)-, and R represents a hydrogen atom or a monovalent organic group.

8. The liquid crystal aligning agent according to claim 1, wherein The total proportion of the structural unit b-1Db1, the structural unit b-1Db2, and the structural unit b-1Db3 relative to 1 mol of all structural units derived from diamine in the polyamic acid B is 60 mol% or more.

9. The liquid crystal alignment agent according to claim 7, wherein The diamine other than diamine 0 in the structural unit 1D-2 is selected from p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, m-phenylenediamine, 2,4-dimethyl-m-phenylenediamine, 1,4-diamino-2,5-dimethoxybenzene, 2,5-diaminotoluene, 2,6-diaminotoluene, 4-aminobenzylamine, 2-(4-aminophenyl)ethylamine, a semiaromatic diamine having a secondary amino group and a primary amino group, 4-(2-aminoethyl)aniline, 2-(6-aminonaphthyl)ethylamine, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl, 3-trifluoromethyl-4 The present invention is selected from the group consisting of: 4'-diaminobiphenyl, 2-trifluoromethyl-4,4'-diaminobiphenyl, 3-fluoro-4,4'-diaminobiphenyl, 2-fluoro-4,4'-diaminobiphenyl, 2,2'-difluoro-4,4'-diaminobiphenyl, 3,3'-difluoro-4,4'-diaminobiphenyl, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,3'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 4,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,2'-diaminobiphenyl, 2,3'-diaminobiphenyl, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 2,5-diaminonaphthalene, 2,6-diaminonaphthalene, and 2,7-diaminonaphthalene.

10. A method for manufacturing a liquid crystal alignment film, comprising: The liquid crystal aligning agent according to any one of claims 1 to 9 is applied to a substrate and a film obtained by baking is irradiated with polarized radiation.

11. The method for manufacturing a liquid crystal alignment film according to claim 10, wherein: The firing temperature in the firing is 150 to 250°C. 12 . A liquid crystal alignment film, formed from the liquid crystal alignment agent according to claim 1 . 13 . A liquid crystal display element comprising the liquid crystal alignment film according to claim 12 . The liquid crystal display element according to claim 13 , which adopts an IPS drive method or an FFS drive method.

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