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

Abstract

Provided is a liquid crystal alignment film in which variation in the twist angle of liquid crystal is small and the generated electrical charge can be reduced in a short time.　Also provided is a liquid crystal alignment agent characterized by containing the polymer (A) and the polymer (B) indicated below.　Polymer (A): a polyimide (A) that is an imidized product of a polyimide precursor having a structural unit represented by formula (1Ta), a structural unit derived from "H-N(Z)-Ar1-L1-A-L1'-Ar1'-N(Z)-H", and a structural unit represented by formula (1Da1). (The definition of each symbol is as described in the specification.)　Polymer (B): a polyamic acid (B) having a structural unit represented by formula (1Tb) and a structural unit represented by formula (1Db). Chemical Formula (1) (The definition of each symbol is as described in the specification.) Chemical Formula (2) (The definition of each symbol is as described in the specification.) Chemical Formula (3) (The definition of each symbol is as described in the specification.)

Description

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

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

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

[0003] Currently, the most widely used industrial liquid crystal alignment films are produced by performing an alignment treatment on the surface of a film made of a polymer, typically polyamic acid and / or imidized polyimide, formed on an electrode substrate. In recent years, as liquid crystal display elements have become higher in performance, resolution, and size, photo-alignment methods have been investigated, in which liquid crystal alignment ability is imparted by irradiating polarized radiation. Proposed photo-alignment methods include those utilizing photoisomerization reactions, photo-crosslinking reactions, and photodecomposition reactions (see, for example, Non-Patent Document 1 and Patent Document 1).

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

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

[0006] In recent years, large-screen, high-resolution liquid crystal display elements have become mainstream, and small display devices such as smartphones, tablet PCs, and car navigation systems have become increasingly popular. This has led to an even greater demand for higher quality liquid crystal display elements. In particular, as liquid crystal display elements are enlarged, variations (non-uniformity) in the twist angle of the liquid crystal within the liquid crystal alignment film surface are likely to occur. Therefore, a liquid crystal aligning agent capable of producing a liquid crystal alignment film that can reduce the variation in the twist angle of the liquid crystal has been desired. Furthermore, in recent high-brightness liquid crystal display elements, the backlight brightness has increased, increasing the visibility of afterimages due to accumulated charge, and therefore a liquid crystal alignment film that can reduce the generated charge in a short period of time is required. In light of the above, an object of the present invention is to provide a liquid crystal aligning agent capable of producing a liquid crystal alignment film that reduces the variation in the twist angle of the liquid crystal and can reduce the generated charge in a short period of time, a liquid crystal alignment film obtained from the liquid crystal aligning agent, and a liquid crystal display element.

[0007] As a result of intensive research to achieve the above object, the present inventors have found that using a liquid crystal alignment agent containing a specific polyimide and a specific polyamic acid is extremely effective in achieving the above object, and have completed the present invention.

[0008] The present invention includes the following aspects.

[0009] A liquid crystal aligning agent comprising the following polymer (A) and polymer (B):

[0010] Polymer (A): Polyimide (A) is an imidized product of a polyimide precursor having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, wherein the structural unit derived from the tetracarboxylic acid derivative is a unit represented by the following formula (1T ａ The diamine-derived structural unit includes a structural unit (a-1Ta) represented by the formula (a-1Ta), and the diamine-derived structural unit includes a diamine (Nh) represented by the formula (H-N(Z)-Ar １ -L １ -A-L １’ -Ar １’ -N(Z)-H" derived structural unit (a-1Da Ｎｈ ), and the following formula (1D ａ１A polyimide containing a structural unit (a-1Da1) represented by the formula (Ar １ , Ar １’ each independently represents a benzene ring, a biphenyl structure, or a naphthalene ring; Ar １ and Ar １’ At least one of Ar represents a naphthalene ring. １ , Ar １’ Any hydrogen atom on the ring may be substituted with a monovalent group. A represents a divalent organic group having an alkylene structure and having 4 to 18 carbon atoms. L １ , L １’ each independently represent a single bond, —O—, —S—, —C(═O)—, —O—C(═O)—, —C(═O)—O—, —NR— (R represents a hydrogen atom or a monovalent organic group), —C(═O)—NR— (R represents a hydrogen atom or a monovalent organic group), or —NR—C(═O)— (R represents a hydrogen atom or a monovalent organic group).) Polymer (B): A polyamic acid (B) having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, wherein the structural unit derived from the tetracarboxylic acid derivative is a compound represented by the following formula (1T ｂ As a diamine-derived structural unit, a structural unit (b-1Tb) represented by the following formula (1D ｂ (b-1Db) wherein R is a hydrogen atom or a carbon atom;

[0011]

[0012] (Formula (1T ａ ) Medium X ａ represents a tetravalent organic group represented by the following formula (x-1): ａ１ ) Medium, D Ｎ represents a monovalent organic group having a thermally detachable group. R and Z each independently represent a hydrogen atom or a monovalent organic group.

[0013]

[0014] (In formula (x-1), R １ ~R ４each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms and containing a fluorine atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 6 carbon atoms, an alkyloxycarbonyl group having 2 to 6 carbon atoms, or a phenyl group; R １ ~R ４ At least one of represents a group other than a hydrogen atom as defined above. * represents a bond.)

[0015]

[0016] (Formula (1T ｂ ) Medium X ｂ represents a tetravalent organic group derived from an aromatic tetracarboxylic dianhydride. ｂ ) in Y ｂ represents a divalent organic group derived from a diamine. Z represents a group represented by the formula (1D ａ１ ) is synonymous with Z in

[0017] According to the present invention, it is possible to provide a liquid crystal alignment agent that can produce a liquid crystal alignment film that has small variation in the twist angle of the liquid crystal and can reduce generated charges in a short period of time, a liquid crystal alignment film obtained from the liquid crystal alignment agent, and a liquid crystal display element.

[0018] 1 is a schematic cross-sectional view showing an example of an IPS mode in-plane switching liquid crystal display element having a liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention, and FIG. 2 is a schematic cross-sectional view showing an example of an FFS mode in-plane switching liquid crystal display element having a liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention.

[0019] Hereinafter, a liquid crystal alignment agent containing a specific polymer component, a liquid crystal alignment film formed using the liquid crystal alignment agent, and a liquid crystal display element having the liquid crystal alignment film will be described in detail. However, the explanation of the constituent elements described below is an example of one embodiment of the present invention, and the present invention is not limited to these contents.

[0020] In the following description, examples of a "halogen atom" include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Furthermore, "tert-", which means tertiary, is also represented as "t-". "Boc" represents a tert-butoxycarbonyl group, and "Fmoc" represents a 9-fluorenylmethyloxycarbonyl group. "*" represents a bond. <Polymer (A)> (Structural Unit Derived from Tetracarboxylic Acid Derivative in Polymer (A)) The polyimide (A) in the polymer (A) of the present invention contains, as a structural unit derived from a tetracarboxylic acid derivative, a tetracarboxylic acid derivative represented by the above formula (1T ａ The imide compound is a polyimide precursor (A) having a structural unit (a-1Ta) represented by the formula (I). The polyimide (A) may be composed of one or more types, and the structural unit (a-1Ta) may be one or more types. From the viewpoint of improving handleability and liquid crystal alignment properties, the imidization rate of the polyimide (A) is preferably 70 to 95%, and more preferably 70 to 90%.

[0021] The above formula (1T ａ In the above formula, the monovalent organic group for R is a monovalent hydrocarbon group having 1 to 6 carbon atoms, and the methylene group of the hydrocarbon group may be -O-, -S-, -CO-, -COO-, -COS-, -NR ３ --CO-NR ３ -, -Si(R ３ ) ２ - (However, R ３ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbon atoms. ３ If there are two, R ３ may be the same or different from each other, —SO ２ - or the like; a monovalent group in which at least one hydrogen atom bonded to a carbon atom of the above-mentioned monovalent hydrocarbon group or the above-mentioned monovalent group A is substituted with a halogen atom, a hydroxy group, an alkoxy group, a nitro group, an amino group, a mercapto group, a nitroso group, an alkylsilyl group, an alkoxysilyl group, a silanol group, a sulfino group, a phosphino group, a carboxy group, a cyano group, a sulfo group, an acyl group or the like; and a monovalent group having a heterocycle.

[0022] The above formula (1T ａIn the above formula (I), the monovalent organic group for R is preferably an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, or a t-butoxycarbonyl group, more preferably an alkyl group having 1 to 3 carbon atoms, and even more preferably a methyl group.

[0023] The above formula (1T ａ In order to obtain the effects of the present invention, the two R's are preferably each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom or a methyl group.

[0024] The above formula (1T ａ ) X ａ represents a tetravalent organic group represented by the above formula (x-1).

[0025] R in the above formula (x-1) １ ~R ４ Specific examples of the alkyl group having 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, in the above R include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a t-butyl group, and an n-pentyl group. １ ~R ４ Specific examples of the alkenyl group having 2 to 6 carbon atoms, preferably 2 to 4 carbon atoms, in the above R include a vinyl group, a propenyl group, and a butenyl group, which may be linear or branched. １ ~R ４ Specific examples of the alkynyl group having 2 to 6 carbon atoms, preferably 2 to 4 carbon atoms, in the formula (I) include an ethynyl group, a 1-propynyl group, and a 2-propynyl group.

[0026] The above R １ ~R ４ In the formula (I), examples of the monovalent organic group containing a fluorine atom and having 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, include a fluoromethyl group, a trifluoromethyl group, a trifluoromethoxy group, a 2,2,2-trifluoroethyl group, a 2,2,2-trifluoroethoxy group, a pentafluoroethyl group, and a pentafluoropropyl group. ２ and R ３is preferably a hydrogen atom. The above formula (x-1) is preferably one selected from the group consisting of the following formulas (x1-1) to (x1-5).

[0027]

[0028] From the viewpoint of suitably obtaining the effects of the present invention, the structural unit (a-1Ta) contained in the polyimide precursor (A) of the present invention is preferably 60 mol % or more, more preferably 70 mol % or more, and most preferably 100 mol %, relative to 1 mol of all structural units derived from tetracarboxylic acid derivatives contained in the polyimide precursor (A).

[0029] The polyimide precursor (A) of the present invention contains a tetracarboxylic acid derivative-derived structural unit represented by the following formula (2T ａ The structural unit (2-1Ta) may be of one type or of two or more types.

[0030]

[0031] (X in the formula 2ａ represents a tetravalent organic group derived from a tetracarboxylic dianhydride other than the tetravalent organic group represented by the above formula (x-1). ａ ) in ２ａ Specific examples of the tetravalent organic group include a tetravalent organic group having an alicyclic structure with five or more members (T ５ａ ), or a tetravalent organic group obtained by removing two acid anhydride groups from the following tetracarboxylic acid dianhydrides (hereinafter, these may be collectively referred to as "other tetracarboxylic acid dianhydrides").

[0032] acyclic aliphatic tetracarboxylic acid dianhydrides such as 1,2,3,4-butanetetracarboxylic acid dianhydride or tetracarboxylic acid dianhydrides represented by the following formulae (AL-1) to (AL-7); alicyclic tetracarboxylic acid dianhydrides such as 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride (provided that the tetravalent organic group (T ５ａ) excluding tetracarboxylic dianhydrides having the following structure: pyromellitic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 3,3',4,4'-diphenylsulfonetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3',4,4'-diphenylethertetracarboxylic dianhydride, 3,3',4,4'-perfluoroisopropylidenedi(phthalic anhydride), 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic dianhydride Aromatic tetracarboxylic dianhydrides such as hydrates, 4,4'-bis(3,4-dicarboxyphenoxy)-2,2-diphenylpropanoic dianhydride, ethylene glycol bisanhydrotrimellitate, 4,4'-(hexafluoroisopropylidene)diphthalic anhydride, 4,4'-carbonyldiphthalic anhydride, 4,4'-oxydi(1,4-phenylene)bis(phthalic)dianhydride, or 4,4'-methylenedi(1,4-phenylene)bis(phthalic)dianhydride; and also tetracarboxylic dianhydrides described in JP 2010-97188 A.

[0033]

[0034] More preferred examples of the other tetracarboxylic acid dianhydrides include 1,2,3,4-butanetetracarboxylic acid dianhydride, 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, pyromellitic acid dianhydride, 3,3',4,4'-benzophenonetetracarboxylic acid dianhydride, 3,3',4,4'-diphenylsulfonetetracarboxylic acid dianhydride, 1,4,5,8-naphthalenetetracarboxylic acid dianhydride, 2,3,6,7-naphthalenetetracarboxylic acid dianhydride, 3,3',4,4'-diphenylethertetracarboxylic acid dianhydride, 3,3',4,4'-biphenyltetracarboxylic acid dianhydride, and 2,2',3,3'-biphenyltetracarboxylic acid dianhydride.

[0035] The tetravalent organic group (T ５ａ) is preferably a tetravalent organic group having a 5- to 8-membered alicyclic structure, and more preferably a tetravalent organic group having a 5- to 7-membered alicyclic structure. Note that, when the alicyclic structure to which the acid anhydride group is bonded is a polycyclic structure, the alicyclic structure having 5 or more members means that each of the rings contained in the polycyclic structure has 5 or more atoms constituting the ring. Furthermore, the alicyclic structure may be bonded to at least one of the two acid anhydride groups, and may have a chain hydrocarbon structure or an aromatic ring structure together with the alicyclic structure.

[0036] Tetravalent organic group (T ５ａ ) is preferably a compound represented by the following formula (X ５ａ -1) to (X ５ａ -18). ５ａ ) is, from the viewpoint of suitably obtaining the effects of the present invention, (X ５ａ -1) to (X ５ａ -4) is more preferable.

[0037]

[0038] The polyimide precursor (A) has the formula (2T ａ The proportion of the structural unit represented by the formula (I) is preferably 40 mol % or less, more preferably 30 mol % or less, based on 1 mol of all structural units derived from tetracarboxylic acid derivatives contained in the polyimide precursor (A). (Structural Units Derived from Diamine in Polymer (A)) The polyimide precursor (A) in the polymer (A) of the present invention contains, as the structural unit derived from diamine, diamine (Nh) "H-N(Z)-Ar １ -L １ -A-L １’ -Ar １’ -N(Z)-H" derived structural unit (a-1Da Ｎｈ ), and the above formula (1D ａ１ The structural unit (a-1Da1) is represented by the structural unit (a-1Da Ｎｈ ), (a-1Da1) may be one type or two or more types.

[0039] The above formula (1D ａ１ The monovalent organic group of Z in the formula (1T) is preferably any of the above-mentioned groups, including preferred embodiments. ａThe same groups as R in the structural unit (a-1Da Ｎｈ )) Structural unit (a-1Da Ｎｈ ) in which L of the diamine (Nh) １ , L １’ Examples of the monovalent organic group for R in -NR-, -C(=O)-NR-, or -NR-C(=O)- represent an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, an alkenyl group having 2 to 3 carbon atoms, an acyl group having 2 to 3 carbon atoms, an alkylsilyl group having 1 to 3 carbon atoms, an alkoxysilyl group having 1 to 3 carbon atoms, a Boc group, or a monovalent organic group in which at least a portion of the hydrogen atoms in these groups have been substituted with at least either a halogen atom or a hydroxy group.

[0040] Ar of the above diamine (Nh) １ and Ar １’ Examples of the monovalent group that is a substituent for any hydrogen atom on the ring include monovalent groups such as a halogen atom; an alkyl group having 1 to 3 carbon atoms; an alkyl group having 1 to 3 carbon atoms in which at least a portion of the hydrogen atoms is substituted with a halogen atom or a hydroxy group; an alkoxy group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms in which at least a portion of the hydrogen atoms is substituted with at least one of the above halogen atoms and a hydroxy group; an alkenyl group having 2 to 3 carbon atoms; an acyl group having 2 to 3 carbon atoms; an alkylsilyl group having 1 to 3 carbon atoms; an alkoxysilyl group having 1 to 3 carbon atoms; a hydroxy group, and a nitrile group.

[0041] Ar of the above diamine (Nh) １ and Ar １’Specific examples of the alkyl group include 1,4-phenylene, 1,3-phenylene, 2-methyl-1,4-phenylene, 2-ethyl-1,4-phenylene, 2-propyl-1,4-phenylene, 2-butyl-1,4-phenylene, 2-isopropyl-1,4-phenylene, 2-t-butyl-1,4-phenylene, 2-methoxy-1,4-phenylene, 2-ethoxy-1,4-phenylene, 2-propoxy-1,4-phenylene, 2-butoxy-1,4-phenylene, and 2-fluoro-1,4 a benzene ring which may have a substituent such as 4,4'-biphenylylene, 2-methyl-4,4'-biphenylylene, 2-ethyl-4,4'-biphenylylene, 2-propyl-4,4'-biphenylylene, 2-butyl-4,4'-biphenylylene, 2- t-butyl-4,4'-biphenylylene, 2-methoxy-4,4'-biphenylylene, 2-ethoxy-4,4'-biphenylylene, 2-fluoro-4,4'-biphenylylene, 3-methyl-4,4'-biphenylylene, 3-ethyl-4,4'-biphenylylene, 3-propyl-4,4'-biphenylylene, 3-butyl-4,4'-biphenylylene, 3-t-butyl-4,4'-biphenylylene, 3-methoxy-4,4'-biphenylylene, 3-ethoxy-4,4'-biphenylylene biphenyl structures which may have a substituent such as phenylylene, 3-fluoro-4,4'-biphenylylene, 2,2'-dimethyl-4,4'-biphenylylene, 3,3'-dimethyl-4,4'-biphenylylene, 3,3'-biphenylylene, 5-methyl-3,3'-biphenylylene, and 5,5'-dimethyl-3,3'-biphenylylene; and naphthalene rings which may have a substituent such as 1,5-naphthylene, 2,6-naphthylene, and 1-methyl-2,6-naphthylene.

[0042] A in the diamine (Nh) is a divalent organic group having an alkylene structure and having 4 to 18 carbon atoms. Any carbon-carbon bond constituting the alkylene structure may be replaced with a carbon-carbon double bond. A is preferably an alkylene group (q0) having 4 to 18 carbon atoms; a divalent organic group (q1) obtained by inserting, between the carbon-carbon bonds of the alkylene group, -O-, -C(=O)-, -NH-, -O-C(=O)-, -C(=O)-O-, -NR-C(=O)- (R represents a monovalent organic group), -C(=O)-NR- (R represents a monovalent organic group), or -NR- (R represents a monovalent organic 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.

[0043] Here, the monovalent organic group of R in the above-mentioned —NR—C(═O)—NR— is L of the above-mentioned diamine (Nh). １ and L １’ Examples of the structure include the structures exemplified for R in —C(═O)—NR—, which represents:

[0044] Preferred specific examples of (q0), (q1) and (q2) are as follows:

[0045] *-(CH ２ ) ｎ - *, * - (CH ２ ) ｎ１ -O-(CH ２ ) ｎ２ - *, * - (CH ２ ) ｎ１ -NR-(CH ２ ) ｎ２ -*, *-(CH ２ ) ｍ１ -OC(=O)-(CH ２ ) ｎ’ -C(=O)-O-(CH ２ ) ｍ２ -*, *-(CH ２ ) ｍ１ -C(=O)-O-(CH ２ ) ｎ’ -OC(=O)-(CH ２ ) ｍ２ -*, *-(CH ２) ｍ１ -C(=O)-NR-(CH ２ ) ｎ’ -NR-C(=O)-(CH ２ ) ｍ２ -*, *-(CH ２ ) ｍ１ -NR-C(=O)- (CH ２ ) ｎ’ -C(=O)-NR-(CH ２ ) ｍ２ - *, * - (CH ２ ) ｎ１ -NR-C(=O)-NR-(CH ２ ) ｎ２ *In the above chemical formula, R represents a hydrogen atom or a monovalent organic group. The monovalent organic group is L of the above diamine (Nh). １ and L １’ Examples of the structure include the structures exemplified for R in —C(═O)—NR—, which represents the following: Two Rs may be the same or different.

[0046] n is an integer of 4 to 18, more preferably an integer of 4 to 10, and even more preferably an integer of 4 to 6.

[0047] m1 and m2 each independently represent an integer of 0 to 4; n' represents an integer of 4 to 6; the sum of m1, m2, and n' is 4 to 16.

[0048] *-(CH ２ ) ｎ１ -O-(CH ２ ) ｎ２ In -*, n1 and n2 are each independently an integer of 1 to 6, and the sum of n1 and n2 is 4 or greater.

[0049] *-(CH ２ ) ｎ１ -NR-C(=O)-NR-(CH ２ ) ｎ２ -In *, n1 and n2 are each independently an integer of 1 to 6, and the sum of n1 and n2 is 4 to 17.

[0050] *-L １ -A-L １’From the viewpoint of suitably obtaining the effects of the present invention, the following embodiments are preferred for -*. In the following formulae, the definitions of m1, m2, n, n', n1, and n2 are the same as in the formulae above. Furthermore, in the following formulae, R represents a hydrogen atom or a monovalent organic group. When two Rs are present, they each independently have the above definition. As the monovalent organic group, L of the diamine (Nh) is preferred. １ and L １’ Examples of the structure include the structures exemplified for R in —C(═O)—NR—, which represents:

[0051] *-(CH ２ ) ｎ -*, -O-(CH ２ ) ｎ -O-*, *-O-(CH ２ ) ｎ１ -O-(CH ２ ) ｎ２ -O-*, *-O-(CH ２ ) ｎ１ -NR-(CH ２ ) ｎ２ -O-*, *-C(=O)-(CH ２ ) ｎ -C(=O)-*, *-C(=O)-NR-(CH ２ ) ｎ -O-*, *-OC(=O)-(CH ２ ) ｎ -O-*, *-OC(=O)-(CH ２ ) ｎ -OC(=O)-*, *-OC(=O)-(CH ２ ) ｎ -C(=O)-O-*, *-(CH ２ ) ｍ１ -OC(=O)-(CH ２ ) ｎ’ -C(=O)-O-(CH ２ ) ｍ２ -* *-S-(CH ２ ) ｎ -S-*, *-C(=O)-NR-(CH ２ ) ｎ -NR-C(=O)-*, *-C(=O)-O-(CH ２ ) ｎ-OC(=O)-*, *-(CH ２ ) ｍ１ -C(=O)-O-(CH ２ ) ｎ’ -OC(=O)-(CH ２ ) ｍ２ -* *-O-(CH ２ ) ｎ -*, *-S-(CH ２ ) ｎ -*, *-NR-C(=O)-(CH ２ ) ｎ -C(=O)-NR-* *-(CH ２ ) ｍ１ -C(=O)-NR-(CH ２ ) ｎ’ -NR-C(=O)-(CH ２ ) ｍ２ -*, *-(CH ２ ) ｍ１ -NR-C(=O)- (CH ２ ) ｎ’ -C(=O)-NR-(CH ２ ) ｍ２ - *, * - (CH ２ ) ｎ１ -NR-C(=O)-NR-(CH ２ ) ｎ２ -* Furthermore, from the viewpoint of preferably obtaining the effects of the present invention, *-(CH ２ ) ｎ -*, *-O-(CH ２ ) ｎ -O-*, *-O-(CH ２ ) ｎ -* is preferred. Ｎｈ From the viewpoint of suitably achieving the effects of the present invention, it is preferable that each of the groups (h-1) to (h-4) has a divalent organic group represented by any one of the following formulae (h-1) to (h-4). In the above formulae (h-1) to (h-4), the bonding positions of the benzene ring are preferably the 1st and 4th positions, and the bonding positions of the naphthalene ring are preferably the 2nd and 6th positions. Note that the hydrogen atoms on the benzene ring and naphthalene ring in the following formulae (h-1) to (h1-4) may be substituted with a methyl group, a methoxy group, or a fluorine atom.

[0052]

[0053] The structural unit (a-1Da) contained in the polyimide precursor (A) Ｎｈ The proportion of the structural unit (a-1Da1) is preferably 1 to 30 mol %, more preferably 5 to 25 mol %, based on 1 mol of all structural units derived from diamine contained in the polyimide precursor (A). (Structural unit (a-1Da1)) The structural unit (a-1Da1) is a unit represented by the above formula (1D ａ１ ) is a structural unit represented by the above formula (1D ａ１ ) in D Ｎ represents a monovalent organic group having a thermally detachable group. The thermally detachable group is preferably bonded to a heteroatom, and examples of such heteroatoms include a nitrogen atom and an oxygen atom. Specific examples of thermally detachable groups bonded to a nitrogen atom include a carbamate protecting group, an amide protecting group, an imide protecting group, and a sulfonamide protecting group. Of these, carbamate protecting groups are preferred in terms of their high thermal detachability, and specific examples thereof include a Boc group, a benzyloxycarbonyl group, a 1,1-dimethyl-2-haloethyloxycarbonyl group, a 1,1-dimethyl-2-cyanoethyloxycarbonyl group, a 9-fluorenylmethyloxycarbonyl group, an allyloxycarbonyl group, and a 2-(trimethylsilyl)ethoxycarbonyl group. Of these, a Boc group is particularly preferred in terms of its excellent thermal detachability. Specific examples of the thermally detachable group bonded to an oxygen atom include ether-based protecting groups such as methyl, ethyl, t-butyl, benzyl, p-methoxybenzyl, and trityl groups; acetal-based protecting groups such as methoxymethyl, ethoxyethyl, and 2-tetrahydropyranyl groups; acyl-based protecting groups such as acetyl, pivaloyl, benzoyl, and trichloroacetyl groups; allyl-based protecting groups such as allyl and methallyl groups; carbamate-based protecting groups such as Boc groups; and silyl ether-based protecting groups such as trimethylsilyl, triethylsilyl, and t-butyldimethylsilyl groups. From the viewpoint of ease of detachment by heat, the thermally detachable group is preferably a methyl, ethyl, t-butyl, benzyl, 2-tetrahydropyranyl, methoxymethyl, 1-ethoxyethyl, or acetyl group. Ｎ is preferably a monovalent organic group (D) represented by the following formula (D).

[0054]

[0055] In the monovalent organic group (D), Q represents a single bond or a divalent linking group, and R represents a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms (excluding thermally labile groups). In formula (D), D represents a thermally labile group. n is an integer of 1 or 2. From the viewpoint of suitably obtaining the effects of the present invention, R is preferably an alkyl group such as a methyl group, an ethyl group, a propyl group, or a butyl group, or a hydrogen atom, and more preferably a hydrogen atom. The divalent linking group in Q is preferably -C(=O)- or a divalent organic group having 1 to 10 carbon atoms. Specific examples of divalent organic groups having 1 to 10 carbon atoms include -CH ２ -, or an alkylene group having 2 to 10 carbon atoms, provided that any -CH ２ - represents -O-, -O-C(=O)-, -C(=O)-O-, -C(=O)-, -N(R')- (R' represents a hydrogen atom or a methyl group), -N(R')-C(=O)- (R' represents a hydrogen atom or a methyl group), -CR ７ =CR ８ - (R ７ , R ８ are each independently a hydrogen atom, a methyl group, a methoxy group, or a halogen atom. ) or -C≡C- may be substituted. More preferred examples of the divalent linking group in Q include the following structures. Note that n1 to n5 are each independently an integer of 1 to 5. Also, *1 is bonded to a benzene ring, and *2 is bonded to a nitrogen atom. *1-(CH ２ ) ｎ１ -*2, *1-O-(CH ２ ) ｎ２ -*2, *1-C(=O)-O-(CH ２ ) ｎ３ -*2, *1-OC(=O)-(CH ２ ) ｎ４ -*2, *1-C(=O)-NH-(CH ２ ) ｎ５-*2. The proportion of the structural unit (a-1Da1) contained in the polyimide precursor (A) is preferably 1 to 30 mol %, more preferably 5 to 25 mol %, relative to 1 mol of all structural units derived from diamine contained in the polyimide precursor (A). The polyimide precursor (A) in the polymer (A) of the present invention contains, as a structural unit derived from diamine, a structural unit represented by the following formula (1D ａ２ The proportion of the structural unit (a-2Da) is preferably 40 mol % or more, and more preferably 50 mol % or more, based on 1 mol of all diamine-derived structural units contained in the polyimide precursor (A). The proportion of the structural unit (a-2Da) is preferably 98 mol % or less, and more preferably 90 mol % or less, based on 1 mol of all diamine-derived structural units contained in the polyimide precursor (A).

[0056]

[0057] (Formula (1D ａ２ ) in Y ａ２ is a compound represented by the formula (1D ａ１ Z represents a divalent organic group derived from a diamine other than the diamine having hydrogen atoms bonded to both ends of the diamine (Nh) or the diamine of the above formula (1D ａ１ ) and preferred embodiments are also the same as diamine (Nh) and the above formula (1D ａ１ ) is the same as Z in the structural unit (a-2Da). Preferred structural units of the structural unit (a-2Da) include specific diamine (2) "H-N(Z)-Ar ２ -L ２ -A ２ -L ２’ -Ar ２’ The structural unit (2D-1) may be derived from a diamine selected from the group consisting of "H-N(Z)-Ar-N(Z)-H" and diamine (Ph) "H-N(Z)-Ar-N(Z)-H", or a structural unit (2'D-2) derived from a diamine other than the specific diamine (2) (hereinafter also referred to as "other diamine"). ２ , Ar ２’ each independently represents a benzene ring, a biphenyl structure, or an aromatic heterocycle. ２ , Ar ２’Any hydrogen atom on the ring may be substituted with a monovalent group, and the substituent may be Ar １ and Ar １’ The substituents exemplified by Ar ２ and Ar ２’ Specific examples of Ar include １ and Ar １’ In addition to the structures containing a benzene ring or a biphenyl structure exemplified above, the following structures (Ht-1) to (Ht-3) can also be mentioned.

[0058]

[0059] L ２ , L ２’ are each independently L １ , L １’ It is synonymous with: ２ represents a divalent organic group having an alkylene structure and having 1 to 18 carbon atoms.

[0060] Above A ２ is a divalent organic group having an alkylene structure and having 1 to 18 carbon atoms, more preferably a divalent organic group having 1 to 12 carbon atoms, and even more preferably a divalent organic group 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 with a carbon-carbon double bond or a heterocyclic ring. Examples of the heterocyclic ring include a pyrrole ring, an imidazole ring, a pyrazole ring, a triazole ring, a pyridine ring, a pyrimidine ring, a pyridazine ring, a pyrazine ring, an indole ring, a benzimidazole ring, a purine ring, a quinoline ring, an isoquinoline ring, a naphthyridine ring, a quinoxaline ring, a phthalazine ring, a triazine ring, a carbazole ring, an acridine ring, a piperidine ring, a piperazine ring, a pyrrolidine ring, and a hexamethyleneimine ring. Of these, a pyridine ring, a pyrimidine ring, a pyrazine ring, a benzimidazole ring, a piperidine ring, a piperazine ring, a quinoline ring, a carbazole ring, or an acridine ring is preferred.

[0061] A ２ may be, for example, the structures exemplified above as (q0), (q1), and (q2).

[0062] From the viewpoint of suitably achieving the effects of the present invention, the specific diamine (2) is a diamine in which two hydrogen atoms are bonded to a divalent organic group represented by any one of the following formulae (h1-1) to (h1-21): 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, or 4-[4-[(4-aminophenoxy)methyl]-4,5-dihydro-4-methyl-2-oxazolyl]-benzenamine, 4-[4-[(4-aminophenoxy)methyl]-4,5-dihydro-2-oxazolyl]-benzenamine, or the following (d Ｈｔ -1) to (d Ｈｔ Diamines represented by (d-9) are preferred. Ｈｔ -6), (d Ｈｔ -8) is preferably 1,4-bis(p-aminobenzyl)piperazine or 4,4'-[4,4'-propane-1,3-diylbis(piperidine-1,4-diyl)]dianiline.

[0063] In formulae (h1-1) to (h1-19), the bonding positions of the benzene ring are preferably the 1st and 4th positions.

[0064] In formula (h1-4), —CH ２ The total number of - is preferably 2 or more and 10 or less.

[0065] In formulae (h1-7) and (h1-8), —CH ２ The total number of - is 14 or less, and two m's may be the same or different.

[0066] In addition, the hydrogen atoms on the benzene rings of the following formulae (h1-1) to (h1-21) may be substituted with a methyl group, a methoxy group, or a fluorine atom.

[0067]

[0068]

[0069]

[0070]

[0071]

[0072] (Diamine (Ph)) Ar represents a benzene ring, a biphenyl structure, a naphthalene ring, or a divalent organic group represented by the following formula (Im): Any hydrogen atom on the benzene ring, biphenyl structure, or naphthalene ring of Ar may be substituted with a monovalent group, and examples of the monovalent group include a halogen atom; an alkyl group having 1 to 3 carbon atoms; an alkyl group having 1 to 3 carbon atoms in which at least a portion of the hydrogen atoms is substituted with a halogen atom or a hydroxy group; an alkoxy group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms in which at least a portion of the hydrogen atoms is substituted with at least one of the halogen atoms and a hydroxy group; an alkenyl group having 2 to 3 carbon atoms; an acyl group having 2 to 3 carbon atoms; an alkylsilyl group having 1 to 3 carbon atoms; an alkoxysilyl group having 1 to 3 carbon atoms; a hydroxy group; and a nitrile group.

[0073]

[0074] (In formula (Im), X represents a tetravalent organic group obtained by removing two anhydride groups from an acyclic or alicyclic tetracarboxylic acid dianhydride.) X in the above formula (Im) is a group represented by the above formula (x-1), the above formula (X ５ａ -1) to (X ５ａ The divalent organic group represented by formula (Im) above is preferably a tetravalent organic group represented by formula (Im-4), or a tetravalent organic group obtained by removing two anhydride groups from 1,2,3,4-butanetetracarboxylic dianhydride. The divalent organic group represented by formula (Im) above is preferably a structure represented by formulas (Im-1) to (Im-6) below.

[0075]

[0076] Specific preferred examples of the diamine (Ph) include p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, m-phenylenediamine, 2,4-dimethyl-m-phenylenediamine, 1,4-diamino-2,5-methoxybenzene, 2,5-diaminotoluene, 2,6-diaminotoluene, 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 ... Examples of the diaminobiphenyl include 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 diamines in which amino groups are bonded to both ends of a divalent organic group represented by the above formula (Im). (Other Diamines) Examples of the other diamines include the following: 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, and the like;1,4-phenylenebis(4-aminobenzoate), 1,4-phenylenebis(3-aminobenzoate), 1,3-phenylenebis(4-aminobenzoate), 1,3-phenylenebis(3-aminobenzoate), bis(4-aminophenyl)terephthalate, bis(3-aminophenyl)terephthalate, bis(4-aminophenyl)isophthalate, bis(3-aminophenyl)isophthalate; 4,4'-diaminoazobenzene, diaminotolan, Diamines represented by the formulae (D-1) to (D-5), 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]o diamines having a photoalignment group, such as aromatic diamines having a cinnamate structure, typified by [(2,4-trifluorobutoxymethyl)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; 1-(4-(2-(2,4-diaminophenoxy)ethoxy)phenyl) diamines having a radical polymerization initiator function, such as 2-(4-(2-hydroxy-2-methylpropanoyl)phenoxy)ethyl-3,5-diaminobenzoate; diamines having an amide bond, such as 4,4'-diaminobenzanilide, diamines represented by the following formula (D-6), and diamines represented by the following formulas (Am-3) to (Am-6); diamines having a urea bond, such as 1,3-bis(4-aminophenyl)urea;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'-di Aminodiphenylmethane, 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, 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-diaminobenzazole amide, 2,5-bis(4-aminophenyl)pyrrole, 4,4'-(1-methyl-1H-pyrrole-2,5-diyl)bis[benzenamine], 1,4-bis-(4-aminophenyl)-piperazine, 2-N-(4-aminophenyl)pyridine-2,5-diamine, 2-N-(5-aminopyridin-2-yl)pyridine-2,5-diamine, 2-(4-aminophenyl)-5-aminobenzimidazole, 2-(4-aminophenyl)-6 ... heterocycle-containing diamines such as N-aminobenzimidazole, 5-(1H-benzimidazol-2-yl)benzene-1,3-diamine, or diamines represented by the following formulae (z-1) to (z-22), or diamines having at least one nitrogen atom-containing structure (hereinafter also referred to as a specific nitrogen atom-containing structure; the specific nitrogen atom-containing structure is an atomic group other than the two amino groups involved in the polycondensation reaction) selected from the group consisting of a heterocycle containing a nitrogen atom and a secondary or tertiary amino group, typified by diamines having a diphenylamine structure such as 4,4'-diaminodiphenylamine, 4,4'-diaminodiphenyl-N-methylamine, N,N'-bis(4-aminophenyl)-benzidine, N,N'-bis(4-aminophenyl)-N,N'-dimethylbenzidine, or N,N'-bis(4-aminophenyl)-N,N'-dimethyl-1,4-benzenediamine; 2,4-diaminophenol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, 4,4'-diamino-3,3'-dihydroxybiphenyl;Diamines having a carboxy group such as 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 3,5-diaminobenzoic acid, 4,4'-diaminobiphenyl-3-carboxylic acid, 4,4'-diaminodiphenylmethane-3-carboxylic acid, 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, and 4,4'-diaminodiphenylether-3,3'-dicarboxylic acid; 1-(4-amino diamines having a siloxane bond such as 1,3-bis(3-aminopropyl)-tetramethyldisiloxane; acyclic aliphatic diamines such as metaxylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, and hexamethylenediamine; alicyclic diamines such as 1,3-bis(aminomethyl)cyclohexane, 1,4-diaminocyclohexane, and 4,4'-methylenebis(cyclohexylamine); and diamines in which two amino groups are bonded to a group represented by any one of formulas (Y-1) to (Y-167) described in WO2018 / 117239.

[0077]

[0078]

[0079]

[0080]

[0081]

[0082] (X in (z-13) １３ represents a methyl group or a phenyl group.

[0083]

[0084] (In formula (z-19), X １９ represents —C(═O)—, —O—, or —NH—. １９ , R １９’ each independently represents a hydrogen atom or a methyl group. ２２ represents or —NH—.)

[0085] <Polyamic Acid (B)> (Structural Unit Derived from Tetracarboxylic Acid Derivative Contained in Polyamic Acid (B)) The liquid crystal aligning agent of the present invention comprises, together with the polyimide (A), a polyamic acid (B) having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, and the structural unit derived from the tetracarboxylic acid derivative is a polyamic acid (B) having a structure represented by the above formula (1T ｂ The polyamic acid contains the above-mentioned polyamic acid containing a structural unit (b-1Tb) represented by the formula (b-1Tb).

[0086] The polyamic acid (B) may be composed of one kind or two or more kinds. In addition, each of the structural units constituting the polyamic acid (B) may be composed of one kind or two or more kinds.

[0087] The above formula (1T ｂ ) X ｂ Examples of the tetravalent organic group that gives the formula (I) include a tetravalent organic group obtained by removing two anhydride groups (-C(=O)-O-C(=O)-) from an aromatic tetracarboxylic dianhydride.

[0088] Here, the aromatic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups, including at least one carboxy group bonded to an aromatic ring.

[0089] In order to preferably obtain the effects of the present invention, the above X ｂ The tetravalent organic group derived from an aromatic tetracarboxylic dianhydride in X is preferably a tetracarboxylic dianhydride having a benzene ring. ｂ The tetravalent organic group derived from the aromatic tetracarboxylic dianhydride in the formula (2T ａ ) in ２ａ It is a tetravalent organic group obtained by removing two anhydride groups from the aromatic tetracarboxylic dianhydride exemplified above.

[0090] In order to suitably obtain the effects of the present invention, the polyamic acid (B) preferably contains the structural unit (b-1Tb) in an amount of more than 40 mol %, and more preferably 50 mol % or more, relative to 1 mol of all structural units derived from tetracarboxylic acid derivatives contained in the polyamic acid (B).

[0091] The polyamic acid (B) of the present invention contains, as a structural unit derived from a tetracarboxylic acid derivative, a compound represented by the following formula (2T ｂ ) may have a structural unit (b-2Tb) represented by the formula (b-2Tb).

[0092]

[0093] (X in the formula ２ｂ is X ｂ represents a tetravalent organic group other than the above formula (2T ｂ ) in ２ｂ Specific examples of the tetravalent organic group include a tetravalent organic group obtained by removing two anhydride groups from an acyclic aliphatic tetracarboxylic acid dianhydride, and a tetravalent organic group obtained by removing two anhydride groups from an alicyclic tetracarboxylic acid dianhydride.

[0094] Here, the acyclic aliphatic tetracarboxylic acid dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups bonded to a chain hydrocarbon structure. However, it does not have to be composed only of a chain hydrocarbon structure, and it may also have an alicyclic structure or an aromatic ring structure as part of it.

[0095] Alicyclic tetracarboxylic acid dianhydrides are acid dianhydrides obtained by intramolecular dehydration of four carboxy groups, including at least one carboxy group bonded to an alicyclic structure. However, none of these four carboxy groups are bonded to an aromatic ring. Furthermore, they do not necessarily have to be composed solely of an alicyclic structure, and may partially contain a chain hydrocarbon structure or an aromatic ring structure.

[0096] More preferred X ２ｂ is a tetravalent organic group represented by the above formula (x-1), a tetravalent organic group obtained by removing two anhydride groups from 1,2,3,4-cyclobutanetetracarboxylic dianhydride, or a tetravalent organic group having an alicyclic structure with five or more members (T ５ａ), or a tetravalent organic group obtained by removing two anhydride groups from the acyclic aliphatic tetracarboxylic dianhydrides exemplified above as other tetracarboxylic dianhydrides.

[0097] In order to obtain the effects of the present invention, the polyamic acid (B) preferably contains the structural unit (b-2Tb) in an amount of less than 60 mol %, more preferably 50 mol % or less, based on 1 mol of all structural units derived from tetracarboxylic acid derivatives contained in the polyamic acid (B). (Structural Units Derived from Diamines Contained in Polyamic Acid (B)) The polyamic acid (B) in the polymer (B) of the present invention contains, as the structural unit derived from diamines, a structural unit represented by the above formula (1D ｂ The structural unit (b-1Db) may be of one type or of two or more types. ｂ The monovalent organic group of Z in the formula (1D ａ ) is synonymous with Z.

[0098] The structural unit (b-1Db) may be a structural unit derived from a diamine exemplified in the polyimide precursor (A). ｂ is a diamine having a urea bond (e.g., A ２ specific diamine (2) having a urea bond, or the diamines having a urea bond exemplified in the above other diamines), diamines having an amide bond (for example, A ２ The diamine (Ph) is preferably a divalent organic group obtained by removing two amino groups from a diamine selected from the group consisting of the specific diamine (2) having a urea bond, or a diamine having an amide bond exemplified in the above-mentioned other diamines), diamine (Ph), the specific diamine (2) having a heterocycle, the specific diamine having a nitrogen atom-containing structure, the diamine having a carboxy group, the semi-aromatic diamine, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, p-phenylenediamine, and m-phenylenediamine (these are also collectively referred to as "specific divalent organic group (b)").

[0099] The polyamic acid (B) is preferably selected from the group consisting of the above-mentioned Y and the above-mentioned Y, from the viewpoint of reducing the afterimage caused by the residual DC. ｂ is the specific divalent organic group (b) of the formula (1D ｂ ) may be contained in an amount of 5 mol % or more, preferably 10 mol % or more, and more preferably 20 mol % or more, relative to 1 mol of all structural units derived from diamine contained in the polyamic acid (B).

[0100] The above formula (1D ｂ As the monovalent organic group of Z in the above formula (1D ａ ) and Z in the above formula (I) are examples of the structures shown above.

[0101] In the liquid crystal aligning agent of the present invention, from the viewpoint of achieving the effects of the present invention, particularly minimizing afterimages caused by residual DC, the content ratio of polymer (A) to polymer (B) may be 10 / 90 to 90 / 10 by mass ratio [polymer (A) / polymer (B)], 20 / 80 to 90 / 10, or 20 / 80 to 80 / 20. (Production of Polyimide Precursor or Polyimide) Polyamic acid, which is a polyimide precursor, or a derivative thereof is typically produced by reacting a diamine component with a tetracarboxylic acid component. Specifically, the method described in WO 2015 / 012368 can be mentioned.

[0102] In producing the polyimide precursor or polyimide of the present invention, a terminal-capping polymer may be produced using a tetracarboxylic acid component containing a tetracarboxylic acid dianhydride or a derivative thereof, a diamine component containing a diamine, and an appropriate terminal-capping agent. The terminal-capping polymer has the effect of improving the film hardness of the liquid crystal alignment film obtained by coating and improving the adhesion properties between the sealant and the liquid crystal alignment film.

[0103] Examples of the terminals of the polyimide precursor or polyimide in the present invention include an amino group, a carboxy group, an acid anhydride group, or a group derived from an end-capping agent described below. The amino group, carboxy group, and acid anhydride group can be obtained by a conventional condensation reaction or by blocking the terminals with the following end-capping agents.

[0104] Examples of the end-capping agent include acid anhydrides such as acetic anhydride, propionic anhydride, succinic anhydride, citraconic anhydride, maleic anhydride, nadic anhydride, phthalic anhydride, itaconic anhydride, 1,2-cyclohexanedicarboxylic anhydride, 3-hydroxyphthalic anhydride, trimellitic anhydride, 3-(3-trimethoxysilyl)propyl)-3,4-dihydrofuran-2,5-dione, 4,5,6,7-tetrafluoroisobenzofuran-1,3-dione, and 4-ethynylphthalic anhydride; dicarbonate diester compounds such as di-tert-butyl dicarbonate and diallyl dicarbonate; acryloyl chloride, methacryloyl chloride, and nicotinic acid chloride. Examples of the isocyanate include chlorocarbonyl compounds; monoamine compounds such as aniline, 2-aminophenol, 3-aminophenol, 4-aminosalicylic acid, 5-aminosalicylic acid, 6-aminosalicylic acid, 2-aminobenzoic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, and n-octylamine; and isocyanates having an unsaturated bond such as ethyl isocyanate, phenyl isocyanate, naphthyl isocyanate, 2-acryloyloxyethyl isocyanate, and 2-methacryloyloxyethyl isocyanate.

[0105] The proportion of the end-capping agent used is preferably 0.01 to 20 parts by mole, and more preferably 0.01 to 10 parts by mole, per 100 parts by mole of the total of the diamine components used.

[0106] The polystyrene-equivalent weight average molecular weight (Mw) of the polyimide precursor and polyimide measured by gel permeation chromatography (GPC) is preferably 1,000 to 500,000, more preferably 2,000 to 300,000. The molecular weight distribution (Mw / Mn), expressed as the ratio of Mw to the polystyrene-equivalent number average molecular weight (Mn) measured by GPC, is preferably 15 or less, more preferably 10 or less. By having the molecular weight within this range, good liquid crystal alignment properties can be ensured in liquid crystal display elements.

[0107] From the viewpoint of workability, the polyimide precursor and polyimide used in the present invention preferably have a solution viscosity of, for example, 10 to 1,000 mPa·s when made into a solution with a concentration of 10 to 15% by mass. The solution viscosity (mPa·s) of the polymer is a value measured at 25°C using an E-type rotational viscometer for a polymer solution with a concentration of 10 to 15% by mass prepared using a good solvent for the polymer (e.g., γ-butyrolactone, N-methyl-2-pyrrolidone, etc.).

[0108] The polystyrene-equivalent weight average molecular weight (Mw) of the polyimide precursor and polyimide, as measured by gel permeation chromatography (GPC), is preferably 1,000 to 500,000, and more preferably 2,000 to 300,000. The molecular weight distribution (Mw / Mn), expressed as the ratio of Mw to the polystyrene-equivalent number average molecular weight (Mn) measured by GPC, is preferably 15 or less, and more preferably 10 or less. By having the molecular weight within this range, good alignment and stability of the liquid crystal display element can be ensured.

[0109] The liquid crystal aligning agent of the present invention may contain a polymer other than the polymer (A) and the polymer (B). Specific examples of the other polymer include at least one polymer (Q) selected from the group consisting of polyimide precursors other than the polymer (A) and the polymer (B) and polyimides that are imidized products of the polyimide precursors, polysiloxane, polyester, polyamide, polyurea, polyorganosiloxane, cellulose derivative, polyacetal, polystyrene derivative, poly(styrene-maleic anhydride) copolymer, poly(isobutylene-maleic anhydride) copolymer, poly(vinyl ether-maleic anhydride) copolymer, poly(styrene-phenylmaleimide) copolymer, and a polymer selected from the group consisting of poly(meth)acrylate. Specific examples of poly(styrene-maleic anhydride) copolymers include SMA1000, SMA2000, SMA3000 (manufactured by Cray Valley Corporation), and GSM301 (manufactured by Gifu Ceramics Manufacturing Co., Ltd.), a specific example of poly(isobutylene-maleic anhydride) copolymers includes ISOBAN-600 (manufactured by Kuraray Co., Ltd.), and a specific example of poly(vinyl ether-maleic anhydride) copolymers includes Gantrez AN-139 (methyl vinyl ether maleic anhydride resin, manufactured by Ashland Corporation).

[0110] The other polymers may be used singly or in combination of two or more. The content ratio of the other polymers 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 component contained in the liquid crystal aligning agent.

[0111] In this specification, the polymer component is a general term for the polymer (A), the polymer (B), and other polymers contained in the liquid crystal aligning agent. When the polymers contained in the liquid crystal aligning agent are only the polymer (A) and the polymer (B), the polymer component refers to the polymer (A) and the polymer (B). <Liquid Crystal Aligning Agent> The liquid crystal aligning agent of the present invention is used to prepare a liquid crystal alignment film, and takes the form of a coating liquid from the viewpoint of forming a uniform thin film. The liquid crystal aligning agent of the present invention is also preferably a coating liquid containing the above-mentioned polymer component and a solvent.

[0112] The content (concentration) of the polymer component contained in the liquid crystal aligning agent of the present invention can be appropriately changed depending on the setting of the thickness of the coating film to be formed, but from the viewpoint of forming a uniform and defect-free coating film, it is preferably 1 mass % or more relative to the total amount of the liquid crystal aligning agent, and from the viewpoint of storage stability of the solution, it is preferably 10 mass % or less.

[0113] From the viewpoint of suitably obtaining 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 even more preferably 50 parts by mass or more, relative to 100 parts by mass of the 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, relative to 100 parts by mass of the polymer components contained in the liquid crystal aligning agent.

[0114] The solvent contained in the liquid crystal aligning agent is not particularly limited as long as it can uniformly dissolve the polymer component. Specific examples thereof include N,N-dimethylformamide, N,N-dimethylacetamide, N,N-diethylacetamide, N,N-dimethyllactamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethyl sulfoxide, γ-butyrolactone, γ-valerolactone, 1,3-dimethyl-2-imidazolidinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethyl Examples of suitable solvents include N-(n-propyl)-2-pyrrolidone, N-isopropyl-2-pyrrolidone, N-(n-butyl)-2-pyrrolidone, N-(tert-butyl)-2-pyrrolidone, N-(n-pentyl)-2-pyrrolidone, N-(3-methoxypropyl)-2-pyrrolidone, N-(2-ethoxyethyl)-2-pyrrolidone, N-(4-methoxybutyl)-2-pyrrolidone, and N-cyclohexyl-2-pyrrolidone (collectively referred to as "good solvents"). Among these, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N,N-diethylacetamide, 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, and γ-butyrolactone are preferred. The content of the good solvent is preferably 20 to 99% by mass, more preferably 20 to 90% by mass, and particularly preferably 30 to 80% by mass of the total solvent contained in the liquid crystal aligning agent.

[0115] In addition, the solvent contained in the liquid crystal aligning agent is preferably a mixed solvent containing, in addition to the above solvent, a solvent (also called a poor solvent) that improves the coatability when applying the liquid crystal aligning agent and the surface smoothness of the coating film. Specific examples of the poor solvent to be used in combination are listed below, but are not limited thereto. For example, diisopropyl ether, diisobutyl ether, diisobutyl carbinol (2,6-dimethyl-4-heptanol), ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, 4-hydroxy-4-methyl-2-pentanone, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, 3-ethoxybutyl acetate, 1-methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, ethylene glycol monoacetate, ethylene glycol diacetate, propylene carbonate, ethylene carbonate, ethylene glycol monobutyl ether, ethylene glycol monoisoamyl ether, ethylene glycol monohexyl ether, propylene glycol monobutyl ether, 1-(2-butoxyethoxy)-2-propanol Examples of the lactic acid bacteria include propylene glycol monomethyl ether acetate, propylene glycol diacetate, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 2-(2-ethoxyethoxy)ethyl acetate, diethylene glycol diacetate, n-butyl acetate, propylene glycol monoethyl ether acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, butyl 3-methoxypropionate, n-butyl lactate, isoamyl lactate, diethylene glycol monoethyl ether, and diisobutyl ketone (2,6-dimethyl-4-heptanone).The content of the poor solvent is preferably 1 to 80 mass %, more preferably 10 to 80 mass %, and particularly preferably 20 to 70 mass % of the total solvent contained in the liquid crystal aligning agent. The type and content of the poor solvent are appropriately selected depending on the coating device, coating conditions, coating environment, etc. of the liquid crystal aligning agent.

[0116] Of these, diisobutyl carbinol, propylene glycol monobutyl ether, propylene glycol diacetate, diethylene glycol diethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, or diisobutyl ketone is preferred.

[0117] Preferred solvent combinations of a good solvent and a poor solvent include N-methyl-2-pyrrolidone and ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone and ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone and propylene glycol monobutyl ether, N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone, 4-hydroxy-4-methyl-2-pentanone and diethylene glycol diethyl ether, and N-methyl-2-pyrrolidone and γ- butyrolactone, propylene glycol monobutyl ether, and diisobutyl ketone; N-methyl-2-pyrrolidone, γ-butyrolactone, propylene glycol monobutyl ether, and diisopropyl ether; N-methyl-2-pyrrolidone, γ-butyrolactone, propylene glycol monobutyl ether, and diisobutyl carbinol; N-methyl-2-pyrrolidone, γ-butyrolactone, and dipropylene glycol dimethyl ether; and N-methyl-2-pyrrolidone, propylene glycol monobutyl ether, and dipropylene glycol dimethyl ether.

[0118] The liquid crystal aligning agent of the present invention may additionally contain components other than the polymer component and the solvent (hereinafter also referred to as additive components). Examples of such additive components include a compound for increasing the strength of the liquid crystal alignment film (hereinafter also referred to as crosslinking compound), an adhesion aid for increasing the adhesion between the liquid crystal alignment film and the substrate or between the liquid crystal alignment film and a sealant, a dielectric or conductive substance for adjusting the dielectric constant or electrical resistance of the liquid crystal alignment film, or an imidization accelerator for promoting imidization.

[0119] Examples of the crosslinkable compound include at least one crosslinkable compound selected from the group consisting of a crosslinkable compound (c-1) having at least one substituent selected from an epoxy group, an oxetanyl group, an oxazoline structure, a cyclocarbonate group, a blocked isocyanate group, a hydroxy group, and an alkoxy group, and a crosslinkable compound (c-2) having a polymerizable unsaturated group.

[0120] Specific preferred examples of the crosslinkable compounds (c-1) and (c-2) include the following compounds: Examples of compounds having an epoxy group include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol, bisphenol A epoxy resins such as Epicoat 828 (manufactured by Mitsubishi Chemical Corporation), bisphenol F epoxy resins such as Epicoat 807 (manufactured by Mitsubishi Chemical Corporation), and hydrogenated bisphenols such as YX-8000 (manufactured by Mitsubishi Chemical Corporation). phenol A type epoxy resins, biphenyl skeleton-containing epoxy resins such as YX6954BH30 (manufactured by Mitsubishi Chemical Corporation), phenol novolac type epoxy resins such as EPPN-201 (manufactured by Nippon Kayaku Co., Ltd.), (o, m, p-) cresol novolac type epoxy resins such as EOCN-102S (manufactured by Nippon Kayaku Co., Ltd.), compounds in which a tertiary nitrogen atom is bonded to an aromatic carbon atom such as tetrakis(glycidyloxymethyl)methane, N,N,N',N'-tetraglycidyl-1,4-phenylenediamine, N,N,N',N'-tetraglycidyl-2,2'-dimethyl-4.4'-diaminobiphenyl, 2,2-bis[4-(N,N-diglycidyl-4-aminophenoxy)phenyl]propane, and N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane;N,N,N',N'-tetraglycidyl-1,2-diaminocyclohexane, N,N,N',N'-tetraglycidyl-1,3-diaminocyclohexane, N,N,N',N'-tetraglycidyl-1,4-diaminocyclohexane, bis(N,N-diglycidyl-4-aminocyclohexyl)methane, bis(N,N-diglycidyl-2-methyl-4-aminocyclohexyl)methane, bis(N,N-diglycidyl-3-methyl-4-aminocyclohexyl)methane, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, 1,4-bis(N,N-diglycidylaminomethyl) ) cyclohexane, 1,3-bis(N,N-diglycidylaminomethyl)benzene, 1,4-bis(N,N-diglycidylaminomethyl)benzene, 1,3,5-tris(N,N-diglycidylaminomethyl)cyclohexane, 1,3,5-tris(N,N-diglycidylaminomethyl)benzene and other compounds in which a tertiary nitrogen atom is bonded to an aliphatic carbon atom; isocyanurate compounds such as triglycidyl isocyanurate such as TEPIC (manufactured by Nissan Chemical Industries, Ltd.); compounds described in paragraph

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

[0170] to

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

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

[0025] to

[0030] and

[0032] of WO2011 / 155577; Examples of compounds having a blocked isocyanate group include Coronate AP Stable M, Coronate 2503, 2515, 2507, 2513, 2555, and Millionate MS-50 (all manufactured by Tosoh Corporation), and Takenate B-830, B-815N, B-820NSU, B-842N, B-846N, B-870N, B-874N, and B-882N (all manufactured by Mitsui Chemicals, Inc.). Specific examples of commercially available compounds such as the above, compounds represented by the following formulae (bL-1) to (bL-3), compounds having two or more protected isocyanate groups described in paragraphs

[0046] to

[0047] of JP 2014-224978 A, compounds having three or more protected isocyanate groups described in paragraphs

[0119] to

[0120] of WO 2015 / 141598 A, and the like;

[0121]

[0122] Examples of compounds having a hydroxy group and / or an alkoxy group include N,N,N',N'-tetrakis(2-hydroxyethyl)adipamide, compounds represented by the following formulae (pL-1) to (pL-4), 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethoxyphenyl)propane, 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl)-1,1,1,3,3,3-hexafluoropropane, compounds described in WO2015 / 072554 and paragraph

[0058] of JP2016-118753A, compounds described in JP2016-200798A, and compounds described in WO2010 / 074269A;

[0123]

[0124] Examples of crosslinkable compounds having a polymerizable unsaturated group include glycerin mono(meth)acrylate, glycerin di(meth)acrylate (1,2-, 1,3-mixture), glycerin tris(meth)acrylate, glycerol 1,3-diglycerolate di(meth)acrylate, pentaerythritol tri(meth)acrylate, diethylene glycol mono(meth)acrylate, triethylene glycol mono(meth)acrylate, tetraethylene glycol mono(meth)acrylate, pentaethylene glycol mono(meth)acrylate, and hexaethylene glycol mono(meth)acrylate.

[0125] The above compounds are examples of crosslinkable compounds, and are not limited thereto. For example, components other than those described above are disclosed on pages 53

[0105] to 55

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

[0126] When a crosslinkable compound is used, the content of the crosslinkable compound in the liquid crystal aligning agent is preferably 0.5 to 20 parts by mass, more preferably 1 to 15 parts by mass, relative to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent.

[0127] Examples of the adhesion aid include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyl trimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-3-triethoxysilylpropyltriethylenetetramine, N-3-trimethoxysilylpropyltriethylenetetramine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N- Benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxy Examples of silane coupling agents include silane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, tris[3-(trimethoxysilyl)propyl]isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-isocyanatopropyltriethoxysilane.

[0128] When an adhesion aid is used, the content of the adhesion aid in the liquid crystal aligning agent is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, relative to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent.

[0129] Examples of the dielectric or conductive material include monoamines having a nitrogen-containing aromatic heterocycle, such as 3-picolylamine.

[0130] When a dielectric or conductive substance is used, the content of the dielectric or conductive substance in the liquid crystal aligning agent is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, per 100 parts by mass of the polymer component contained in the liquid crystal aligning agent. Examples of the imidization accelerator for promoting the imidization include compounds having a basic moiety (e.g., a primary amino group, an aliphatic heterocycle (e.g., a pyrrolidine skeleton), an aromatic heterocycle (e.g., an imidazole ring, an indole ring), or a guanidino group) (excluding the crosslinkable compounds and compounds for adjusting the dielectric constant or electrical resistance of the liquid crystal alignment film), or compounds that generate the basic moiety upon baking. More preferred are compounds that generate the basic moiety upon baking, and preferred specific examples include amino acids in which some or all of the basic moieties of the amino acid are protected. Examples of protecting groups for the basic moieties of the amino acids include carbamate-based protecting groups such as a Boc group. Specific examples of the amino acid include glycine, alanine, cysteine, methionine, asparagine, glutamine, valine, leucine, phenylalanine, tyrosine, tryptophan, proline, hydroxyproline, arginine, histidine, lysine, and ornithine. More preferred examples of the compound for promoting imidization include N-α-(9-fluorenylmethoxycarbonyl)-N-τ-(tert-butoxycarbonyl)-L-histidine and N-α-(tert-butoxycarbonyl)-N-τ-(tert-butoxycarbonyl)-L-histidine. The content of the imidization promoter contained in the liquid crystal aligning agent of the present invention is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, and even more preferably 5 to 20 parts by mass, per 100 parts by mass of the polymer component contained in the liquid crystal aligning agent. (Liquid Crystal Alignment Film) The liquid crystal alignment film of the present invention is formed using the liquid crystal aligning agent of the present invention.

[0131] The method for producing a liquid crystal alignment film of the present invention comprises, for example, applying the above-mentioned liquid crystal aligning agent to a substrate, baking the applied liquid crystal aligning agent, and irradiating the resulting film with polarized radiation.

[0132] A preferred embodiment of the method for producing a liquid crystal alignment film of the present invention includes, for example, a method for producing a liquid crystal alignment film comprising a step of applying the liquid crystal aligning agent to a substrate (step (1)), a step of baking the applied liquid crystal aligning agent (step (2)), and, optionally, a step of aligning the film obtained in step (2) (step (3)). <Step (1)> The substrate to which the liquid crystal aligning agent used in the present invention is applied is not particularly limited as long as it is a highly transparent substrate, and glass substrates, silicon nitride substrates, and plastic substrates such as acrylic substrates and polycarbonate substrates can also be used. In this case, using a substrate on which an ITO (indium tin oxide) electrode for driving the liquid crystal is formed is preferable from the viewpoint of simplifying the process. Furthermore, in a reflective liquid crystal display device, an opaque material such as a silicon wafer can be used for only one substrate, and in this case, a light-reflecting material such as aluminum can also be used for the electrode. Furthermore, when manufacturing a liquid crystal display element of an IPS drive type or an FFS drive type, a substrate on which an electrode made of a transparent conductive film or a metal film patterned into a comb-tooth shape is provided and an opposing substrate on which no electrode is provided are used.

[0133] Examples of a method for applying the liquid crystal alignment agent to a substrate and forming a film include screen printing, offset printing, flexographic printing, an inkjet method, and a spray method. Among these, the application and film formation method by the inkjet method is preferably used.

[0134] An IPS substrate, which is a comb-tooth electrode substrate used in the IPS system (mode), has a base material, a plurality of linear electrodes formed on the base material and arranged in a comb-tooth pattern, and a liquid crystal alignment film formed on the base material so as to cover the linear electrodes.

[0135] The FFS substrate, which is a comb-tooth electrode substrate used in the FFS method (mode), has a base material, a surface electrode formed on the base material, an insulating film formed on the surface electrode, a plurality of linear electrodes formed on the insulating film and arranged in a comb-tooth shape, and a liquid crystal alignment film formed on the insulating film so as to cover the linear electrodes.

[0136] FIG. 1 is a schematic cross-sectional view showing an example of an IPS mode in-plane switching liquid crystal display device having a liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention.

[0137] In the IPS LCD element 1 illustrated in Fig. 1, liquid crystal 3 is sandwiched between a comb-shaped electrode substrate 2 having a liquid crystal alignment film 2c and a counter substrate 4 having a liquid crystal alignment film 4a. The comb-shaped electrode substrate 2 has a base material 2a, a plurality of linear electrodes 2b formed on the base material 2a and arranged in a comb-like pattern, and a liquid crystal alignment film 2c formed on the base material 2a so as to cover the linear electrodes 2b. 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 2c is a liquid crystal alignment film of the present invention. The liquid crystal alignment film 4c is also a liquid crystal alignment film of the present invention.

[0138] In the IPS LCD element 1 shown in FIG. 1, when a voltage is applied to the linear electrodes 2b, an electric field is generated between the linear electrodes 2b as indicated by electric force lines L.

[0139] FIG. 2 is a schematic cross-sectional view showing an example of an FFS mode in-plane switching liquid crystal display device having a liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention.

[0140] In the IPS LCD element 1 illustrated in Figure 2, liquid crystal 3 is sandwiched between a comb-shaped electrode substrate 2 having a liquid crystal alignment film 2h and a counter substrate 4 having a liquid crystal alignment film 4a. The comb-shaped electrode substrate 2 has a base 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-like pattern, and a liquid crystal alignment film 2h formed on the insulating film 2f so as to cover the linear electrodes 2g. The counter substrate 4 has a base material 4b and a liquid crystal alignment film 4a formed on the base material 4b. The liquid crystal alignment film 2h is a liquid crystal alignment film of the present invention. The liquid crystal alignment film 4a is also a liquid crystal alignment film of the present invention.

[0141] In the IPS LCD element 1 shown in FIG. 2, when a voltage is applied to the surface electrodes 2e and the linear electrodes 2g, an electric field is generated between the surface electrodes 2e and the linear electrodes 2g, as indicated by the electric field lines L. <Step (2)> Step (2) is a step of baking the liquid crystal alignment agent applied to the substrate to form a film. After the liquid crystal alignment agent is applied to the substrate, the solvent can be evaporated or the amic acid or amic acid ester in the polymer can be thermally imidized using a heating means such as a hot plate, a hot air circulation oven, or an IR (infrared) oven. The drying and baking steps after application of the liquid crystal alignment agent of the present invention can be performed at any temperature and for any time, and may be performed multiple times. The temperature for evaporating the solvent in the liquid crystal alignment agent can be, for example, 40 to 180°C as the temperature of the heating means, but may also be 40 to 150°C to shorten the process. The baking time is not particularly limited, but is, for example, 1 to 10 minutes, preferably 1 to 5 minutes. When a step of thermally imidizing the amic acid in the polymer is carried out in addition to the step of evaporating the solvent, the step of evaporating the solvent can be followed by a baking step using a heating means at a temperature in the range of, for example, 150 to 300° C., preferably 150 to 250° C. The baking time in the thermally imidizing step is not particularly limited, but is, for example, 5 to 40 minutes, preferably 5 to 30 minutes.

[0142] If the film-like material after baking is too thin, the reliability of the liquid crystal display element may decrease, so the thickness is preferably 5 to 300 nm, and more preferably 10 to 200 nm. <Step (3)> Step (3) is a step of performing an alignment treatment on the film obtained in step (2). Alignment treatment methods for liquid crystal alignment films include rubbing treatment and photo-alignment treatment, with photo-alignment treatment being preferred. Examples of photo-alignment treatment methods include irradiating the surface of the film-like material with polarized radiation in a certain direction, and optionally performing a heat treatment to impart liquid crystal alignment properties (also referred to as liquid crystal alignment ability). As the radiation, ultraviolet light or visible light having a wavelength of 100 to 800 nm can be used. Of these, ultraviolet light having a wavelength of 100 to 400 nm is preferred, and more preferably 200 to 400 nm.

[0143] The radiation dose is 1 to 10,000 mJ / cm２ is preferred, and 100 to 5,000 mJ / cm ２ is more preferred.

[0144] Examples of light sources that can be used for the irradiation light include low-pressure mercury lamps, high-pressure mercury lamps, deep UV lamps, deuterium lamps, metal halide lamps, argon resonance lamps, xenon lamps, mercury-xenon lamps, excimer lasers (e.g., KrF excimer lasers), fluorescent lamps, LED lamps, halogen lamps (e.g., sodium lamps), and microwave-excited electrodeless lamps.

[0145] Furthermore, when polarized light is used as the irradiation light, the higher the extinction ratio of the polarized light, the higher the anisotropy that can be imparted. For example, in the case of ultraviolet light, the extinction ratio of polarized ultraviolet light is more preferably 10:1 or more, and even more preferably 20:1 or more.

[0146] In addition, when irradiating with radiation, in order to improve the liquid crystal alignment, the substrate having the film-like material may be irradiated while being heated at 50 to 250° C. The liquid crystal alignment film thus produced can stably align liquid crystal molecules in a certain direction.

[0147] Furthermore, the liquid crystal alignment film irradiated with polarized radiation by the above method can be contacted with a solvent or the liquid crystal alignment film irradiated with radiation can be heat-treated.

[0148] The solvent used in the contact treatment is not particularly limited, as long as it dissolves the decomposition products generated from the film-like material by irradiation with radiation. Specific examples include water, methanol, ethanol, 2-propanol, acetone, methyl ethyl ketone, 1-methoxy-2-propanol, 1-methoxy-2-propanol acetate, butyl cellosolve, ethyl lactate, methyl lactate, diacetone alcohol, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propyl acetate, butyl acetate, and cyclohexyl acetate. Among these, water, 2-propanol, 1-methoxy-2-propanol, and ethyl lactate are preferred from the viewpoints of versatility and solvent safety. Water, 1-methoxy-2-propanol, and ethyl lactate are more preferred. The solvent may be one type or a combination of two or more types.

[0149] Examples of the contact treatment include immersion treatment and spray treatment (also referred to as spray treatment). The treatment time in these treatments is preferably 10 seconds to 1 hour from the viewpoint of efficiently dissolving the decomposition products generated from the film-like material by irradiation with radiation. In particular, immersion treatment for 1 minute to 30 minutes is more preferable. The solvent used in the contact treatment may be at room temperature or heated, preferably 10 to 80°C, and more preferably 20 to 50°C. In addition, ultrasonic treatment or the like may be performed as necessary from the viewpoint of the solubility of the decomposition products.

[0150] After the contact treatment, it is preferable to perform rinsing (also called "rinsing") with a low-boiling solvent such as water, methanol, ethanol, 2-propanol, acetone, or methyl ethyl ketone, and then calcination. In this case, either rinsing or calcination may be performed, or both may be performed. The calcination temperature is preferably 150 to 300°C, more preferably 180 to 250°C, and even more preferably 200 to 230°C. The calcination time is preferably 10 seconds to 30 minutes, and more preferably 1 minute to 10 minutes.

[0151] The heat treatment of the coating film irradiated with the radiation is preferably carried out for 1 to 30 minutes at 50 to 300° C., and more preferably for 1 to 30 minutes at 120 to 250° C. (Liquid Crystal Display Element) The liquid crystal display element of the present invention has the liquid crystal alignment film of the present invention.

[0152] The liquid crystal alignment film of the present invention is suitable as a liquid crystal alignment film for a liquid crystal display element of a horizontal electric field type such as an IPS type or an FFS type, from the viewpoint of obtaining high liquid crystal alignment properties, and is particularly useful as a liquid crystal alignment film for a liquid crystal display element of an FFS type.

[0153] A liquid crystal display element can be produced by obtaining a substrate with a liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention, preparing a liquid crystal cell by a known method, and arranging liquid crystals in the liquid crystal cell. Specifically, the following two methods can be mentioned.

[0154] In the first method, two substrates are placed opposite each other with a gap (cell gap) between them so that their liquid crystal alignment films face each other, and then the peripheries of the two substrates are bonded together using a sealant. A liquid crystal composition is injected into the substrate surfaces and the cell gap defined by the sealant so that it comes into contact with the film surface, and the injection hole is then sealed.

[0155] The second method is called the ODF (One Drop Fill) method. For example, a UV-curable sealant is applied to a predetermined location on one of two substrates on which a liquid crystal alignment film has been formed, and a liquid crystal composition is then dropped onto several predetermined locations on the liquid crystal alignment film surface. The other substrate is then attached so that the liquid crystal alignment film faces the other substrate, and the liquid crystal composition is spread over the entire surface of the substrate and brought into contact with the film surface. Next, the entire surface of the substrate is irradiated with UV light to cure the sealant.

[0156] In either the first method or the second method, it is further desirable to heat the liquid crystal composition used to a temperature at which it assumes an isotropic phase, and then slowly cool it to room temperature to remove flow alignment that occurs during liquid crystal filling.

[0157] When the coating films are subjected to a rubbing treatment, the two substrates are arranged to face each other so that the rubbing directions of the coating films are at a predetermined angle, for example, perpendicular or antiparallel. Similarly, when a photo-alignment treatment is performed, the substrates are arranged to face each other so that the alignment directions are at a predetermined angle, for example, perpendicular or antiparallel.

[0158] The sealing agent may be, for example, an epoxy resin containing a hardener and aluminum oxide spheres as spacers. The liquid crystal may be a nematic liquid crystal or a smectic liquid crystal, with a nematic liquid crystal being preferred.

[0159] The liquid crystal composition is not particularly limited, and is a composition containing at least one liquid crystal compound (liquid crystal molecule), and either a liquid crystal composition having a positive dielectric anisotropy (also called a positive liquid crystal composition or positive liquid crystal) or a liquid crystal composition having a negative dielectric anisotropy (also called a negative liquid crystal composition or negative liquid crystal) may be used, but negative liquid crystal materials are preferred.

[0160] The liquid crystal composition may contain a liquid crystal compound having a fluorine atom, a hydroxy group, an amino group, a fluorine atom-containing group (e.g., a trifluoromethyl group), a cyano group, an alkyl group, an alkoxy group, an alkenyl group, an isothiocyanate group, a heterocycle, a cycloalkane, a cycloalkene, a steroid skeleton, a benzene ring, or a naphthalene ring, or may contain a compound having two or more rigid moieties (mesogenic skeletons) that exhibit liquid crystal properties within the molecule (e.g., a bimesogenic compound in which two rigid biphenyl structures or terphenyl structures are connected by an alkyl group). The liquid crystal composition may be a liquid crystal composition exhibiting a nematic phase, a liquid crystal composition exhibiting a smectic phase, or a liquid crystal composition exhibiting a cholesteric phase.

[0161] In order to improve the alignment properties of the liquid crystal, the liquid crystal composition may further contain additives, such as photopolymerizable monomers having a polymerizable group as described below, optically active compounds (e.g., S-811 manufactured by Merck), antioxidants, ultraviolet absorbers, dyes, antifoaming agents, polymerization initiators, or polymerization inhibitors.

[0162] Examples of the positive liquid crystal include ZLI-2293, ZLI-4792, MLC-2003, MLC-2041, MLC-3019, and MLC-7081 manufactured by Merck.

[0163] Examples of negative liquid crystals include MLC-6608, MLC-6609, MLC-6610, MLC-6882, MLC-6886, MLC-7026, MLC-7026-000, MLC-7026-100, and MLC-7029 manufactured by Merck.

[0164] In the PSA mode, MLC-3023 manufactured by Merck is an example of a liquid crystal containing a compound having a polymerizable group.

[0165] Next, polarizing plates are installed. Specifically, a pair of polarizing plates are attached to the surfaces of the two substrates opposite the liquid crystal layer. Examples of polarizing plates include a polarizing film called an "H film" made by stretching and aligning polyvinyl alcohol and absorbing iodine, sandwiched between cellulose acetate protective films, and a polarizing plate made of the H film itself.

[0166] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. The abbreviations of the compounds used and the methods for measuring the properties are as follows: (Organic solvents) NMP: N-methyl-2-pyrrolidone BCS: ethylene glycol monobutyl ether GBL: γ-butyrolactone (Tetracarboxylic acid dianhydride) TC-1 to TC-3: Compounds represented by the following formulas (TC-1) to (TC-3), respectively

[0167]

[0168] (Diamine) DA-X1: Compound represented by the following formula (DA-X1) DA-X2: Compound represented by the following formula (DA-X2) DA-1 to DA-7: Compounds represented by the following formulas (DA-1) to (DA-7), respectively

[0169]

[0170]

[0171] (Additives) AD-1 to AD-4: Compounds represented by the following formulas (AD-1) to (AD-4), respectively

[0172]

[0173] <Viscosity Measurement> Measurement was carried out using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.) with a sample volume of 1.1 mL and a cone rotor TE-1 (1°34', R24) at a temperature of 25°C. <Molecular Weight Measurement> Measurement was carried out using the following room temperature GPC (gel permeation chromatography) apparatus under the following conditions, and Mn (number average molecular weight) and Mw (weight average molecular weight) were calculated as polyethylene glycol oxide equivalent values.

[0174] GPC apparatus: GPC-101 (manufactured by Resonac), column: GPC KD-803, GPC KD-805 (manufactured by Resonac) in series, column temperature: 50°C, eluent: N,N-dimethylformamide (additive: lithium bromide monohydrate (LiBr.H ２ o) at 30 mmol / L, anhydrous crystalline phosphoric acid (o-phosphoric acid) at 30 mmol / L, tetrahydrofuran (THF) at 10 mL / L), flow rate: 1.0 mL / min. Standard sample for creating a calibration curve: EasiVial PEG / PEO polyethylene glycol oxide PL2080-0201 (molecular weight: about 1,500, about 4,000, about 13,000, about 30,000, about 70,000, about 130,000, about 500,000, about 1,000,000, about 1,500,000) (manufactured by GL Sciences). <Measurement of imidization rate> 20 mg of polyimide powder was placed in an NMR sample tube (NMR sampling tube standard, φ5 (Kusano Scientific Co., Ltd.)), 1.0 mL of deuterated dimethyl sulfoxide ([D6]-DMSO, 0.05% tetramethylsilane (TMS) mixture) was added, and the mixture was sonicated to completely dissolve. 500 MHz proton NMR of this solution was measured using a Fourier transform superconducting nuclear magnetic resonance (FT-NMR) "AVANCE III" (BRUKER).

[0175] The (chemical) imidization rate was determined by the following formula, using a proton derived from a structure that remains unchanged before and after imidization as a reference proton, and the peak integrated value of this proton and the peak integrated value of a proton derived from the NH group of the amic acid that appears around 9.5 to 10.0 ppm: In the formula, x represents the peak integrated value of the proton derived from the NH group of the amic acid, y represents the peak integrated value of the reference proton, and α represents the ratio of the number of reference protons to one proton of the NH group of the amic acid in the case of polyamic acid (with an imidization rate of 0%).

[0176] Imidization rate (%) = (1 - α x / y) x 100 [Polymer synthesis] <Synthesis Example 1> DA-2 (3.91 g, 16.0 mmol), DA-1 (0.519 g, 4.80 mmol), DA-X1 (1.79 g, 4.80 mmol), DA-X2 (1.52 g, 6.40 mmol), and NMP (88.9 g) were added to a 100 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature (25 ° C) while supplying nitrogen. Thereafter, TC-1 (6.67 g, 29.8 mmol) and NMP (16.7 g) were added, and the mixture was stirred at 40 ° C for 15 hours to obtain a polyamic acid solution (viscosity: 200 mPa s) with a solids concentration of 12% by mass. The Mn of this polyamic acid was 9,847 and the Mw was 20,024.

[0177] The polyamic acid solution (35.0 g) obtained above was weighed into a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and NMP was added to a solids concentration of 11.67 mass %. Acetic anhydride (2.86 g) and pyridine (0.370 g) were then added. The mixture was stirred at room temperature (25°C) for 30 minutes, and then reacted at 55°C for 3 hours. This reaction solution was poured into methanol (249 g), and the resulting precipitate was filtered off. This precipitate was washed with methanol and dried under reduced pressure at 80°C to obtain a polyimide (A-1) powder. The imidization rate of this polyimide powder was 75%, with an Mn of 10,404 and an Mw of 19,738.

[0178] NMP was added to the obtained polyimide powder (3.57 g) so that the solids concentration was 15% by mass, and the mixture was stirred at 70°C for 20 hours to dissolve the polyimide, yielding a solution of polyimide (A-1) (viscosity: 200 mPa·s). The polyimide had an Mn of 9,627 and an Mw of 18,810. <Synthesis Example 2> DA-2 (12.3 g, 50.2 mmol), DA-X2 (2.10 g, 8.85 mmol), TC-1 (12.1 g, 54.1 mmol), and NMP (194 g) were added to a 200 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and the mixture was stirred at 40°C for 3 hours to yield a polyamic acid solution with a solids concentration of 12% by mass (viscosity: 200 mPa·s). The polyamic acid had an Mn of 12,900 and an Mw of 38,600.

[0179] The resulting polyamic acid solution (200 g) was weighed into a 300 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and NMP was added to a solids concentration of 9% by mass. Acetic anhydride (16.4 g) and pyridine (4.25 g) were then added. The mixture was stirred at room temperature (25°C) for 30 minutes, and then reacted at 55°C for 3 hours. This reaction solution was poured into methanol (1435 g), and the resulting precipitate was filtered off. This precipitate was washed with methanol and dried under reduced pressure at 80°C to obtain a polyimide (A-R1) powder. The imidization rate of this polyimide powder was 70%, with an Mn of 13,900 and an Mw of 40,100.

[0180] NMP was added to the obtained polyimide powder so that the solids concentration was 12% by mass, and the mixture was stirred at 70°C for 20 hours to dissolve the polyimide, yielding a solution of polyimide (A-R1) (viscosity: 140 mPa s). The polyimide had an Mn of 14,600 and an Mw of 40,300. <Synthesis Example 3> DA-2 (4.45 g, 18.2 mmol), DA-1 (0.454 g, 4.20 mmol), DA-X2 (1.33 g, 5.60 mmol), and NMP (71.6 g) were placed in a 100 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and the mixture was stirred at room temperature (25°C) while supplying nitrogen to dissolve the polyimide. Thereafter, TC-1 (5.84 g, 26.0 mmol) and NMP (16.9 g) were added and stirred at 40° C. for 15 hours to obtain a polyamic acid solution (viscosity: 200 mPa s) with a solids concentration of 12% by mass. The polyamic acid had an Mn of 9,900 and an Mw of 20,024.

[0181] The resulting polyamic acid solution (35.0 g) was weighed into a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and NMP was added to a solids concentration of 11.67 mass %. Acetic anhydride (2.86 g) and pyridine (0.370 g) were then added. The mixture was stirred at room temperature (25°C) for 30 minutes, and then reacted at 55°C for 3 hours. This reaction solution was poured into methanol (249 g), and the resulting precipitate was filtered off. This precipitate was washed with methanol and dried under reduced pressure at 80°C to obtain a polyimide (A-R2) powder. The imidization rate of this polyimide powder was 75%, with an Mn of 10,070 and an Mw of 19,637.

[0182] NMP was added to the obtained polyimide powder (3.57 g) so that the solids concentration was 15% by mass, and the mixture was stirred at 70°C for 20 hours to dissolve the polyimide, yielding a solution of polyimide (A-R2) (viscosity: 200 mPa·s). The polyimide had an Mn of 9,876 and an Mw of 18,600. <Synthesis Example 4> DA-4 (3.10 g, 10.4 mmol), DA-3 (8.28 g, 41.6 mmol), TC-3 (14.7 g, 49.9 mmol), and NMP (191 g) were added to a 200 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and the mixture was stirred at 70°C for 15 hours to yield a solution of polyamic acid (B-1) with a solids concentration of 12% by mass (viscosity: 461 mPa·s). The polyamic acid had an Mn of 10,467 and an Mw of 22,986. Synthesis Example 5 DA-4 (1.37 g, 4.60 mmol), DA-3 (2.75 g, 13.8 mmol), DA-5 (1.15 g, 4.60 mmol), TC-3 (6.33 g, 21.5 mmol), and NMP (85.0 g) were placed in a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and the mixture was stirred at 70° C. for 15 hours to obtain a solution of polyamic acid (B-2) (viscosity: 389 mPa s) with a solids concentration of 12% by mass. The Mn of this polyamic acid was 9,641 and the Mw was 21,301. Synthesis Example 6 DA-4 (1.37 g, 4.60 mmol), DA-3 (1.83 g, 9.20 mmol), and DA-5 (2.29 g, 9.20 mmol) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and the mixture was stirred at 40°C for 0.5 hours while supplying nitrogen. Thereafter, TC-3 (6.33 g, 21.5 mmol) and NMP (86.7 g) were added, and the mixture was stirred at 70°C for 15 hours to obtain a solution of polyamic acid (B-3) with a solids concentration of 12% by mass (viscosity: 442 mPa s). The Mn of this polyamic acid was 10,067, and the Mw was 22,319. Synthesis Example 7 DA-3 (11.1 g, 55.9 mmol), DA-7 (2.13 g, 14.0 mmol), and NMP (97.3 g) were placed in a 200 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and the mixture was stirred at room temperature (25° C.) while supplying nitrogen to dissolve the mixture.Thereafter, TC-3 (19.2 g, 65.2 mmol) and NMP (140 g) were added, and the mixture was stirred at 70°C for 12 hours to obtain a solution of polyamic acid (B-4) (viscosity: 120 mPa s) with a solids concentration of 12% by mass. The Mn of this polyamic acid was 9,700 and the Mw was 21,800. <Synthesis Example 8> DA-4 (16.1 g, 54.1 mmol), DA-6 (5.41 g, 36.0 mmol), and NMP (174 g) were added to a 200 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and the mixture was dissolved by stirring at room temperature (25°C) while supplying nitrogen. After cooling to 15°C, TC-2 (16.9 g, 86.3 mmol) and NMP (43.9 g) were added and stirred at room temperature (25°C) for 2 hours to obtain a solution of polyamic acid (B-R1) with a solids concentration of 15% by mass (viscosity: 740 mPa s). The polyamic acid had an Mn of 10,933 and an Mw of 28,600. <Synthesis Example 9> DA-1 (3.46 g, 32.0 mmol), DA-4 (14.3 g, 48.0 mmol), and NMP (160 g) were added to a 200 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature (25°C) while supplying nitrogen. After cooling to 15°C, TC-2 (5.48 g, 27.9 mmol) and NMP (10.6 g) were added and stirred at room temperature (25°C) for 1 hour. Thereafter, TC-2 (9.08 g, 46.3 mmol) and NMP (66.8 g) were added and stirred at room temperature (25°C) for 1 hour to obtain a solution of polyamic acid (B-R2) with a solids concentration of 12% by mass (viscosity: 124 mPa s). This polyamic acid had an Mn of 8,057 and an Mw of 19,377.

[0183] The types and amounts of the tetracarboxylic acid components and diamine components used in Synthesis Examples 1 to 9 are shown in Table 1. In Table 1, the numbers in parentheses for the tetracarboxylic acid components represent the proportion (parts by mole) of each compound used relative to 100 parts by mole of the total amount of the tetracarboxylic acid components used in the synthesis of each polymer. The numbers for the diamine components represent the proportion (parts by mole) of each compound used relative to 100 parts by mole of the total amount of the diamine components used in the synthesis of each polyamic acid. The "-" symbol for the imidization rate indicates that the compound is a polyamic acid.

[0184]

[0185] [Preparation of Liquid Crystal Alignment Agent] Example 1 The polyimide solution (A-1) and the polyamic acid solution (B-1) obtained in Synthesis Example 1 were diluted with NMP, GBL, and BCS, and then AD-1, AD-2, and AD-3 were added and stirred at room temperature (25°C) for 15 hours. As a result, a polymer solution (AL-1) was obtained in which the mass ratio of the solid contents of the polymers (A-1:B-1) was 30:70, the mass ratio of the polymer solid contents to the solvents (polymer solid contents:NMP:GBL:BCS) was 5.7:44.3:30:20, and the blending ratio of AD-1 was 5 parts by mass, the blending ratio of AD-2 was 1 part by mass, and the blending ratio of AD-3 was 7 parts by mass per 100 parts by mass of the polymer. <Examples 2 and 3, and Comparative Examples 1 to 4> The liquid crystal aligning agents AL-2 and AL-3, which are Examples 2 and 3 of the present invention, and liquid crystal aligning agents AL-C1 to AL-C4, which are Comparative Examples 1 to 4, were obtained by the same operation as in Example 1, except that the polyimide solution and polyamic acid solution used were changed as shown in Table 2.

[0186]

[0187] In Table 2, the numerical values ​​in parentheses for the polymer components represent the blending ratio (parts by mass) of each polymer relative to a total of 100 parts by mass of the polymers contained in each liquid crystal alignment agent. The numerical values ​​in parentheses for the additive components represent the blending ratio (parts by mass) of each additive component relative to a total of 100 parts by mass of the polymers contained in each liquid crystal alignment agent. [Preparation of FFS Drive Liquid Crystal Cell] A liquid crystal cell having the configuration of an FFS mode liquid crystal display element was prepared.

[0188] First, a substrate with electrodes was prepared. The substrate was a rectangular glass substrate measuring 30 mm x 50 mm and 0.7 mm thick. A solid-patterned ITO electrode constituting a common electrode was formed on the substrate as the first layer. A SiN (silicon nitride) film deposited by CVD (chemical vapor deposition) was formed on the first common electrode as the second layer. The second SiN film had a thickness of 300 nm, which served as an interlayer insulating film. A comb-shaped pixel electrode formed by patterning an ITO film as the third layer was placed on the second SiN film. Two pixels, a first pixel and a second pixel, were formed, each measuring 10 mm long and 5 mm wide. This electrode-equipped substrate had a structure in which the first common electrode and the third pixel electrode were insulated by the second SiN film.

[0189] The pixel electrode of the third layer had a comb-like shape with the central portion bent at an interior angle of 160° and multiple electrode lines, each 3 μm wide, arranged parallel to each other at intervals of 6 μm. One pixel was formed by multiple electrode lines and had a first region and a second region separated by a line connecting the bent portions.

[0190] Next, the liquid crystal alignment agents (AL-1) to (AL-3) and (AL-C1) to (AL-C4) obtained in Examples 1 to 3 and Comparative Examples 1 to 4 were each filtered through a filter with a pore size of 1.0 μm, and then applied by spin coating to the electrode-attached substrate (hereinafter referred to as the electrode substrate) and a glass substrate (hereinafter referred to as the counter substrate) having a 4 μm-high columnar spacer with an ITO film formed on the back surface. After drying for 2 minutes on a hot plate at 80 ° C, the film was baked for 20 minutes in a hot air circulation oven at 230 ° C to form a coating film with a thickness of 100 nm. 250 mJ / cm of polarized ultraviolet light was applied to the coating surface through a 254 nm bandpass filter and a polarizer. ２The substrate was then irradiated with an exposure dose of 1000 kJ / cm, and further baked in an IR oven at 230°C for 30 minutes to perform an alignment treatment, yielding a substrate with a liquid crystal alignment film. The liquid crystal alignment film formed on the electrode substrate was oriented so that the direction dividing the interior angles of the pixel bends was parallel to the liquid crystal alignment direction, and the liquid crystal alignment film formed on the counter substrate was oriented so that the alignment direction of the liquid crystal on the electrode substrate coincided with the alignment direction of the liquid crystal on the counter substrate when the liquid crystal cell was fabricated. The two substrates were combined into a pair, and a sealant (Mitsui Chemicals, Inc., XN-1500T) was printed on one substrate using a dispenser. Another substrate was then attached to the pair, facing each other with the alignment directions of the liquid crystal alignment films aligned at 0°. The bonded substrates were then pressure-bonded and heated in a circulating hot air oven at 150°C for 60 minutes to cure the sealant, producing an empty cell. Negative liquid crystal MLC-7026-100 (manufactured by Merck) was injected into this empty cell by a vacuum injection method, and the injection port was sealed to obtain an FFS-driven liquid crystal cell. The obtained liquid crystal cell was then heated at 120°C for 1 hour and left at 23°C overnight before being used for evaluation. [Evaluation of In-Plane Uniformity of Contrast] The twist angle variation of the liquid crystal cell was evaluated using an AxoStep manufactured by AXOMETRICS. The liquid crystal cell prepared above was placed on a measurement stage, and the distribution of circular retardance within the pixel plane was measured with no voltage applied, and 3σ, which is three times the standard deviation σ, was calculated. The smaller the 3σ value, the better the in-plane uniformity. As evaluation criteria, a 3σ value less than 1.70 was rated "A," a 3σ value greater than 1.70 but equal to or less than 2.00 was rated "B," and a 3σ value greater than 2.00 was rated "C." The results are shown in Table 3. [Measurement of Relaxation Rate of Accumulated Charge] The liquid crystal cell prepared above was placed between two polarizing plates arranged so that their polarization axes were perpendicular to each other. The pixel electrode and the common electrode were short-circuited to have the same potential. An LED backlight was irradiated from below the two polarizing plates. The angle of the liquid crystal cell was adjusted so that the luminance of the LED backlight transmitted through the two polarizing plates was minimized. Next, a 30 Hz AC voltage was applied to the liquid crystal cell, and the V-T curve (voltage-transmittance curve) was measured. The AC voltage at which the relative transmittance was 23% was calculated as the driving voltage.

[0191] For the evaluation of image retention, the liquid crystal cell was driven for 30 minutes by applying an AC voltage of 30 Hz, which gave a relative transmittance of 23%, while simultaneously applying a DC voltage of 1 V. Thereafter, the application of the DC voltage alone was stopped, and the cell was driven for another 10 minutes by the AC voltage alone, and the relative transmittance was measured.

[0192] The evaluation criteria were as follows: if the relative transmittance relaxed to 27% or less within 10 minutes after the application of the DC voltage was stopped, it was rated as "A", and if it took 10 minutes or more for the relative transmittance to decrease to 27% or less, it was rated as "C". The results are shown in Table 3.

[0193] The evaluation of the afterimage according to the above-mentioned method was carried out under a temperature condition where the temperature of the liquid crystal cell was 23°C.

[0194]

[0195] As shown in Table 3, the liquid crystal display devices using the liquid crystal aligning agents of Examples 1 to 3 were excellent in both the in-plane uniformity of contrast and the relaxation speed of accumulated charges.

[0196] The entire contents of the specification, claims, drawings and abstract of Japanese Patent Application No. 2024-109236 filed on July 5, 2024 are hereby incorporated by reference as the disclosure of the specification of the present invention.

[0197] 1: In-plane switching liquid crystal display element, 2: comb-tooth electrode substrate, 2a: substrate, 2b: linear electrode, 2c: liquid crystal alignment film, 2d: substrate, 2e: plane electrode, 2f: insulating film, 2g: linear electrode, 2h: liquid crystal alignment film, 3: liquid crystal, 4: opposing substrate, 4a: liquid crystal alignment film, 4b: substrate, L: electric field line

Claims

1. A liquid crystal aligning agent comprising the following polymer (A) and polymer (B): Polymer (A): Polyimide (A) is an imidized product of a polyimide precursor having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, wherein the structural unit derived from the tetracarboxylic acid derivative is represented by the following formula (1T ａ The diamine-derived structural unit includes a structural unit (a-1Ta) represented by the formula (a-1Ta), and the diamine-derived structural unit includes a diamine (Nh) "H-N(Z)-Ar １ -L １ -A-L １’ -Ar １’ -N(Z)-H" derived structural unit (a-1Da Ｎｈ ), and the following formula (1D ａ１ A polyimide containing a structural unit (a-1Da1) represented by the formula (Ar １ , Ar １’ each independently represents a benzene ring, a biphenyl structure, or a naphthalene ring; Ar １ and Ar １’ At least one of Ar represents a naphthalene ring. １ , Ar １’ Any hydrogen atom on the ring may be substituted with a monovalent group. A represents a divalent organic group having an alkylene structure and having 4 to 18 carbon atoms. L １ , L １’ each independently represent a single bond, —O—, —S—, —C(═O)—, —O—C(═O)—, —C(═O)—O—, —NR— (R represents a hydrogen atom or a monovalent organic group), —C(═O)—NR— (R represents a hydrogen atom or a monovalent organic group), or —NR—C(═O)— (R represents a hydrogen atom or a monovalent organic group).) Polymer (B): A polyamic acid (B) having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, wherein the structural unit derived from the tetracarboxylic acid derivative is a compound represented by the following formula (1T ｂ As a diamine-derived structural unit, a structural unit (b-1Tb) represented by the following formula (1D ｂ (b-1Db) wherein R is a hydrogen atom or a carbon atom; (Formula (1T ａ ) Medium X ａ represents a tetravalent organic group represented by the following formula (x-1): ａ１ ) Medium, D Ｎ represents a monovalent organic group having a thermally detachable group. R and Z each independently represent a hydrogen atom or a monovalent organic group. (In formula (x-1), R １ ~R ４ each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms and containing a fluorine atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 6 carbon atoms, an alkyloxycarbonyl group having 2 to 6 carbon atoms, or a phenyl group; R １ ~R ４ At least one of represents a group other than a hydrogen atom as defined above. * represents a bond.) (Formula (1T ｂ ) Medium X ｂ represents a tetravalent organic group derived from an aromatic tetracarboxylic dianhydride. ｂ ) in Y ｂ represents a divalent organic group derived from a diamine. Z represents a group represented by the formula (1D ａ１ ) is synonymous with Z in 2. The liquid crystal aligning 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): (* represents a bond.) 3. The polyimide precursor (A) contains, as a diamine-derived structural unit, a structural unit represented by the following formula (1D ａ２ 2. The liquid crystal aligning agent according to claim 1, having a structural unit (a-2Da) represented by the formula: (Formula (1D ａ２ ) in Y ａ２ is a diamine (Nh) or the above formula (1D ａ１ Z represents a divalent organic group derived from a diamine other than the diamine having hydrogen atoms bonded to both ends of the diamine (Nh) or the diamine represented by the formula (1D ａ１ ) is synonymous with Z in 4. A method for producing a liquid crystal alignment film, comprising applying the liquid crystal aligning agent according to any one of claims 1 to 3 to a substrate, baking the applied film, and irradiating the resulting film with polarized radiation.

5. The method for producing a liquid crystal alignment film according to claim 4, wherein the baking temperature is 150 to 250°C.

6. A liquid crystal alignment film formed from the liquid crystal aligning agent according to any one of claims 1 to 3.

7. A liquid crystal display device comprising the liquid crystal alignment film according to claim 6.

8. The liquid crystal display element according to claim 7, which is of an IPS drive system or an FFS drive system.

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