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

Abstract

Provided are: a liquid crystal aligning agent which contains two or more polyamic acids and in which deterioration in liquid crystal aligning properties when stored at room temperature is suppressed; a liquid crystal alignment film obtained from the liquid crystal aligning agent; and a liquid crystal display element. The liquid crystal aligning agent is characterized by containing the following polymer (A) and polymer (B). Polymer (A): a polyamic acid (A) having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, the polyamic acid containing, as the structural unit derived from the tetracarboxylic acid derivative, a structural unit (a-1Ta) represented by formula (1Ta), and containing, as the structural unit derived from the diamine, a structural unit (a-1Da) represented by formula (1Da), at least a part of the terminal of the polyamic acid (A) contains a non-amino group, the non-amino group is a functional group represented by structural formula (E), and the presence rate of the terminal amino group in the polyamic acid (A) is 60% or less based on the total terminal of the polyamic acid (A). Polymer (B): a polyamic acid (B) having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, the polyamic acid including a structural unit (b-1Tb) represented by formula (1Tb) as the structural unit derived from the tetracarboxylic acid derivative, and including a structural unit (b-1Db) represented by formula (1Db) as the structural unit derived from the diamine. (Definition of each symbol is as defined in the specification) (Definition of each symbol is as defined in the specification) (Definition of each symbol is as defined in the specification) (Definition of each symbol is as defined in the specification)

Description

TECHNICAL FIELD

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

[0002] Conventionally, liquid crystal display devices are widely used as display sections of personal computers, smartphones, portable telephones, television receivers, and the like. A liquid crystal display device has, for example, a liquid crystal layer interposed between a device 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 of the liquid crystal layer, a thin film transistor (TFT) that converts an electric signal supplied to the pixel electrodes, and the like. As a driving method of the liquid crystal molecules, a longitudinal electric field method such as a TN (Twisted Nematic) method, a VA (Vertical Alignment) method, and the like, and a lateral electric field method such as an IPS (In-Plane Switching) method, an FFS (Fringe Field Switching) method, and the like are known.

[0003] Currently, the most popular liquid crystal alignment film in industry is produced by performing alignment treatment on the surface of a film composed of a polymer represented by polyamic acid and / or polyimide produced by imidization of the same, which is formed on an electrode substrate. In recent years, with the high performance, high definition, and large size of liquid crystal display elements, a photo-alignment method of imparting liquid crystal alignment ability by irradiation of polarized radiation has been studied. For the photo-alignment method, a method using a photo-isomerization reaction, a method using a photo-crosslinking reaction, a method using a photo-decomposition reaction, and the like are proposed (for example, refer to Non-Patent Literature 1, Patent Literature 1).

[0004] PRIOR ART DOCUMENTS

[0005] PATENT LITERATURE

[0006] Patent Literature 1: Japanese Patent Application Laid-Open (JP-A) No. 9-297313

[0007] NON-PATENT LITERATURE

[0008] Non-Patent Literature 1: "Liquid Crystal Photo-Alignment Film", Kido Yutaka, Ichimura Shigeru, Functional Materials, November 1997, Vol. 17, No. 11, pp. 13-22 SUMMARY

[0009] PROBLEMS TO BE SOLVED BY THE INVENTION

[0010] In the past, as a liquid crystal alignment agent for a liquid crystal alignment film of a liquid crystal display element of the lateral electric field system, a liquid crystal alignment agent containing a polyimide has been actively studied. However, although the polyimide has excellent liquid crystal alignment properties, on the other hand, it has a disadvantage of insufficient solubility in an organic solvent. Therefore, in the case where the polyimide is dissolved in an organic solvent, a polar organic solvent having high solubility such as N-methylpyrrolidone is used. However, although the polar organic solvent has high solubility, on the other hand, it has a disadvantage of high hygroscopicity. Therefore, in the case where a liquid crystal alignment film is produced using a liquid crystal alignment agent containing the above polar organic solvent, from the viewpoint of improving the properties of the obtained liquid crystal alignment film, there arises a need to control the coating environment of the liquid crystal alignment agent. In particular, when coating is performed in an environment having high humidity, the solubility of the liquid crystal alignment agent decreases due to hygroscopicity before heat treatment, the polyimide precipitates, and sometimes a problem of whitening (hygroscopic whitening) of the liquid crystal alignment film occurs.

[0011] Further, the production of the polyimide requires a large amount of reagents, a large-scale production apparatus, and there are problems in terms of operability (safety, environmental load, equipment cost, etc.).

[0012] The present inventors have focused on a liquid crystal alignment agent using a polyamic acid in view of the above circumstances. However, it is known that, in the case where a liquid crystal alignment agent containing two or more kinds of polyamic acids having different characteristics is used, it is preferable from the viewpoint of the suppression of the above hygroscopic whitening and operability, on the other hand, the deterioration of the liquid crystal alignment properties is accelerated during storage.

[0013] In particular, it is known that, in the case of a liquid crystal alignment film for a liquid crystal display element represented by the IPS system and the FFS system, a high alignment restricting force for suppressing afterimage (hereinafter also referred to as AC afterimage) generated by long-term AC drive is required, but there arises a problem that a liquid crystal alignment film that responds to such a high level of requirements cannot necessarily be obtained.

[0014] According to the above, an object of the present application is to provide a liquid crystal alignment agent, a liquid crystal alignment film obtained from the liquid crystal alignment agent, and a liquid crystal display element, in which the deterioration of the liquid crystal alignment properties during storage at room temperature is suppressed, and two or more kinds of polyamic acids are contained.

[0015] Approach for solving the problem

[0016] The present inventors have conducted intensive studies in order to solve the above technical problems, and as a result, have found that the use of a liquid crystal alignment agent containing: a first polyamic acid having a specific non-amino terminal structure, and having a specific structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine; and a second polyamic acid having a specific structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, is extremely effective for achieving the above objects, and thus have completed the present application.

[0017] The present application includes the following solutions.

[0018] A liquid crystal alignment agent characterized by containing a polymer (A) and a polymer (B) described below.

[0019] Polymer (A): a polyamic acid (A) having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, the polyamic acid containing a structural unit (a-1Ta) represented by the following formula (1T a ) as the structural unit derived from a tetracarboxylic acid derivative, and containing a structural unit (a-1Da) represented by the following formula (1D a ) as the structural unit derived from a diamine, the terminal of at least a part of the polyamic acid (A) containing a non-amino group which is a functional group represented by the following structural formula (E), the presence ratio of the terminal amino group of the polyamic acid (A) being 60% or less based on the total terminals of the polyamic acid (A).

[0020] Polymer (B): a polyamic acid (B) having a structural unit derived from a tetracarboxylic acid derivative and a structural unit derived from a diamine, the polyamic acid containing a structural unit (b-1Tb) represented by the following formula (1T b ) as the structural unit derived from a tetracarboxylic acid derivative, and containing a structural unit (b-1Db) represented by the following formula (1D b ) as the structural unit derived from a diamine.

[0021]

[0022] (In the formula, X a represents a tetravalent organic group represented by the following formula (x-1). In the formula (1D a ), Y a represents a divalent organic group derived from a diamine. Z each independently represents a hydrogen atom or a monovalent organic group.)

[0023]

[0024] (In the formula (x-1), R1 to R4 each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 6 carbon atoms, an alkoxycarbonyl group having 2 to 6 carbon atoms, or a phenyl group, at least one of R1 to R4 representing a group other than the hydrogen atom as defined above. * represents a bonding bond.)

[0025]

[0026] (In the formula, Xb This refers to a tetravalent organic group derived from an aromatic tetracarboxylic acid dianhydride, a tetravalent organic group represented by the following formula (x-2), or a tetravalent organic group with an alicyclic structure having five or more members (T). 5a Equation (1D) b ), Y b This represents a divalent organic group derived from a diamine. Z is related to the above formula (1D). a The meaning of Z is the same as that of )

[0027]

[0028]

[0029] (In formula (E), Q is a monovalent organic group selected from any of the groups (e1) to (e3) listed below. * indicates a bond.)

[0030] (e1) Non-cyclic hydrocarbon groups with 1 to 6 carbon atoms.

[0031] (e2) A monovalent organic group having 1 to 2 carboxyl groups and 2 to 30 carbon atoms (wherein, the monovalent organic group does not contain anhydride groups).

[0032] (e3) A monovalent organic group having two or more Boc atoms, and excluding Boc atoms, having a carbon number of 1 to 30, wherein the monovalent organic group has a protected amino group selected from the group consisting of *1-NH(Boc), *1-N(Boc)2, and "*1-N(Boc)-*1" (*1 represents a bond bonded to a carbon atom). It should be noted that when there are two or more protected amino groups, the protected amino groups may optionally be the same or different.

[0033] Invention Effects

[0034] According to the present invention, a liquid crystal alignment agent, a liquid crystal alignment film obtained from the liquid crystal alignment agent, and a liquid crystal display element are provided, wherein the degradation of liquid crystal alignment when the liquid crystal alignment agent is stored at room temperature is suppressed, and the liquid crystal alignment agent contains two or more polyamic acids. Attached Figure Description

[0035] Figure 1 This is a schematic cross-sectional view showing an example of an IPS mode lateral electric field liquid crystal display element having a liquid crystal alignment film obtained by the liquid crystal alignment agent of the present invention.

[0036] Figure 2 This is a schematic cross-sectional view showing an example of a lateral electric field liquid crystal display element having an FFS mode liquid crystal alignment film obtained by the liquid crystal alignment agent of the present invention. Detailed Implementation

[0037] 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. The description of the necessary conditions for the construction described below is an example of one embodiment of the present invention and is not specific to these contents.

[0038] In the following explanation, the following can be listed as "halogen atoms": fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc. Furthermore, "tert-" representing tertiary is also represented as "t-". "Boc" represents tert-butoxycarbonyl, and "*" represents a bonded bond.

[0039] (Terminal amino group)

[0040] The liquid crystal alignment agent of the present invention comprises the polymer (A) and polymer (B) described above. At least a portion of the polyamic acid (A) in polymer (A) has a non-amino group at its terminal, which is a functional group represented by the above structural formula (E). That is, preferably, at least a portion of the terminal amino groups of the polyamic acid (A) are modified in a manner that includes the non-amino group.

[0041] The presence of terminal amino groups in polyamic acid (A) is less than 60% based on all the terminals of polyamic acid (A).

[0042] It should be noted that at least a portion of the terminal portion of the polyamic acid (B) in the polymer (B) of the present invention may also contain the non-amino group. That is, preferably, at least a portion of the terminal amino group of the polyamic acid (B) may also be modified to have the non-amino group.

[0043] From the viewpoint of obtaining the appropriate effects of the present invention, the non-amino group that may be included at the end of the polyamic acid (B) can be listed as the functional group shown in the structure (E) of the polyamic acid (A) in the polymer (A), and the same functional group can be listed as a preferred embodiment.

[0044] The “presence of terminal amino groups” as used herein refers, for example, in the case of polyamic acid (A), to the percentage of terminal amino groups based on all the ends of polyamic acid (A), expressed in % (%).

[0045] It should be noted that "based on all the ends of polyamic acid (A)" means setting the total number of amino and non-amino ends of polyamic acid (A) to 100%, including the total number of any end being 0%.

[0046] The presence rate of terminal amino groups can be used 1H-NMR is used to estimate the concentration based on the change in peak intensity of the terminal amino group. The presence of terminal amino groups in the polyamic acid (A) used in this invention is preferably 30% or less, more preferably 10% or less, and even more preferably 1% or less. Furthermore, the presence of terminal amino groups in the polyamic acid (A) used in this invention can also be 0%. That is, all ends of the polyamic acid (A) used in this invention may also contain the non-amino group.

[0047] The non-amino group is the functional group shown in the above structural formula (E). The functional group shown in the above structural formula (E) is preferably bonded to the nitrogen atom of the diamine residue.

[0048] Specific examples of preferred compounds (e1) above include: methyl, ethyl, propyl, butyl, pentyl, hexyl, vinyl, and methacryl.

[0049] As a preferred example of (e1) above, residues derived from substances such as acetic anhydride, acrylic anhydride, methacrylic anhydride, propionic anhydride, butyric anhydride, valeric anhydride, isovaleric anhydride, hexanoic anhydride, or heptanoic anhydride are listed.

[0050] As a preferred specific example of (e2) above, a monovalent organic group having residues derived from dicarboxylic anhydrides and having 1 to 2 carboxyl groups (wherein the monovalent organic group does not contain an anhydride group) can be listed.

[0051] As specific examples of the dicarboxylic anhydrides that provide the above (e2), compounds that do not have an alkoxysilane structure (e2-1) and compounds that have an alkoxysilane structure (e2-2) can be listed.

[0052] Specific examples of compounds (e2-1) include: phthalic anhydride, maleic anhydride, succinic anhydride, allyl succinic anhydride, itaconic anhydride, trimellitic anhydride, 1,2,4-cyclohexanetricarboxylic acid-1,2-anhydride, 4-ethynyl phthalic anhydride, or cyclohexene-1,2-dicarboxylic anhydride, etc., which are aromatic or aliphatic cyclic dicarboxylic anhydrides.

[0053] The aliphatic ring in the above-mentioned aliphatic cyclic dicarboxylic anhydride can be a saturated aliphatic ring or an unsaturated aliphatic ring.

[0054] Specific examples of compounds (e2-2) include: 3-trimethoxysilylpropyl succinic anhydride, 3-triethoxysilylpropyl succinic anhydride, 4-(3-trimethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-triethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-trimethoxysilylpropyl)phthalic anhydride, 4-(3-triethoxysilylpropyl)phthalic anhydride; 2-(methoxydimethylsilyl)ethyl succinic anhydride, 3-(dimethylmethoxysilyl)propyl succinic anhydride or 3-(dimethylethoxysilyl)propyl succinic anhydride, etc. (1-6 carbon atoms) alkoxydimethylsilyl (2-8 carbon atoms) alkyl succinic anhydride; 2-(dimethoxymethylsilyl) Alkyl)ethyl succinic anhydride and other di(carbon 1-6)alkoxymethylsilyl(carbon 2-8)alkyl succinic anhydride; 2-(trimethoxysilyl)ethyl succinic anhydride, 2-(triethoxysilyl)ethyl succinic anhydride, [3-(trimethoxysilyl)propyl] succinic anhydride or [3-(triethoxysilyl)propyl] succinic anhydride and other tri(carbon 1-6)alkoxysilyl(carbon 2-8)alkyl succinic anhydride; 4-(3-dimethylmethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-dimethylethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-dimethylmethoxysilylpropyl)phthalic anhydride or 4-(3-dimethylethoxysilylpropyl)phthalic anhydride.

[0055] In the above (e3), it is preferable that, from the viewpoint of properly obtaining the effects of the present invention, the number of protected amino sites is one or more, and from the viewpoint of the effect of liquid crystal orientation, the number of protected amino sites is four or less.

[0056] The above (e3) is obtained, for example, using the active ester compound (e) shown in R-O-C(=O)-E3 (R represents the active ester forming group. E3 represents the above (e3)).

[0057] Here, "active ester-forming group" refers to the following chemical group: together with the carbonyl group to which it is bonded, in a coupling reaction with an amino-containing compound that forms an amide group, or other coupling reactions, to form an ester that activates the aforementioned carbonyl group.

[0058] Examples of active ester-forming groups include those formed by removing the hydroxyl group from the following hydroxyl compounds: 1-hydroxybenzotriazole (HOBt), 1-hydroxy-7-azobenzotriazole (HOAt), N-hydroxysuccinimide (HOSu), ethyl 2-cyano-2-(hydroxyimino)acetate (oxyma), 3,4-dihydro-3-hydroxy-4-oxo-1,2,3-benzotriazine (HOOBt or HODhbt), N-hydroxy-5-norbornene-2,3-dicarboximide (HONB), 2,3,4,5,6-pentafluorophenol (HOPfp), or 6-chloro-1-hydroxy-1H-benzotriazole (Cl-HOBt), etc. (See, for example, the catalogue of WATANABE Chemical, Amino acids and chiral building blocks to new medicine. Hereinafter, they are also collectively referred to as hydroxyl compounds (Ae)). From the viewpoint of obtaining the appropriate effects of the present invention, it is preferable to have a group formed by removing the hydroxyl group from HOBt, HOAt, HOSu or HOOBt, and more preferably a group formed by removing the hydroxyl group from HOBt, HOAt or HOOBt.

[0059] Furthermore, from the viewpoint of properly obtaining the effects of the present invention, it is more preferable that E3 has two or more of the above-mentioned protective amino sites when the active ester forming group represents a group derived from HOSu.

[0060] The above-mentioned active ester compound (e3) is synthesized, for example, from a carboxylic acid (W-COOH) (W has the same meaning as (e3) above. Hereinafter, it is also referred to as carboxylic acid (W)) and the above-mentioned hydroxyl compound (Ae).

[0061] As for the organic groups in W that do not include the Boc group and have 1 to 30 carbon atoms, the organic groups with 1 to 12 carbon atoms are preferred, and the organic groups with 1 to 6 carbon atoms are more preferred.

[0062] The above-mentioned carboxylic acid (W) has two or more Boc groups and has a group in the molecule having a protected amino site selected from the group consisting of *1-NH(Boc), *1-N(Boc)2 and "*1-N(Boc)-*1" (*1 represents a bond bonded to a carbon atom).

[0063] The aforementioned carboxylic acid (W) is obtained, for example, by protecting the amino groups of a carboxyl-containing polyamine (pA), represented by a carboxyl-containing diamine, which has two or more amino groups. It should be noted that the amino group protection can be applied to a portion of the amino groups in the amine, or to all of the amino groups.

[0064] Specific examples of polyamines (pA) include: diaminobenzoic acids such as 3,5-diaminobenzoic acid; carboxybiphenyl compounds such as 4,4'-diaminobiphenyl-3-carboxylic acid; carboxydiphenylalkanes such as 4,4'-diaminodiphenylmethane-3-carboxylic acid or 4,4'-diaminodiphenylethane-3-carboxylic acid; aromatic polyamines represented by carboxydiphenyl ethers such as 4,4'-diaminodiphenylether-3-carboxylic acid or 4,4'-diaminodiphenylether-3-carboxylic acid; and aliphatic polyamines such as arginine, lysine, ornithine, or histidine.

[0065] Regarding the aforementioned carboxylic acids (W) and polyamines (pA), from the viewpoint of appropriately obtaining the effects of the present invention, it is preferable to have a heterocycle containing a nitrogen atom or a derivative thereof. Specific examples of such a nitrogen-containing heterocycle include: aziridine, aziridine butane, pyrrole, imidazole, imidazoline, pyrrolidine, piperidine, piperazine, morpholine, pyrazole, indole, benzimidazole, or carbazole. Furthermore, specific examples of derivatives of the nitrogen-containing heterocycle include compounds formed by substituting any hydrogen atom of the nitrogen-containing heterocycle with substituents.

[0066] Examples of substituents mentioned above include: alkyl groups with 1 to 4 carbon atoms that are linear or branched, alkoxy groups with 1 to 4 carbon atoms that are linear or branched, hydroxyl groups, halogen atoms, nitro groups, cyano groups, trifluoromethyl groups, -NR7R8 or -CONR7R8 groups, where R7 and R8 each independently represent a hydrogen atom and an alkyl group with 1 to 4 carbon atoms that are linear or branched.

[0067] As a preferred specific example of the above-mentioned active ester compound (e3), any of the compounds shown in the following formulas (e3-1) to (e3-4) are preferred.

[0068]

[0069] <Polyamic Acid (A)>

[0070] (The structural units of polyamic acid (A) derived from tetracarboxylic acid derivatives)

[0071] The polyamic acid (A) in the polymer (A) of the present invention has the above formula (1T) a The structural unit (a-1Ta) shown is a structural unit derived from a tetracarboxylic acid derivative. It should be noted that the polymer (A) can be composed of one or more types, and the structural unit (a-1Ta) can be composed of one or more types.

[0072] The above formula (1T) a X a This represents the tetravalent organic group shown in the above formula (x-1).

[0073] Specific examples of alkyl groups having 1 to 6 carbon atoms, preferably 1 to 4, in R1 to R4 of the above formula (x-1) include: methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, etc. Specific examples of alkenyl groups having 2 to 6 carbon atoms, preferably 2 to 4, in R1 to R4 include: vinyl, propenyl, butenyl, etc., which can be linear or branched. Specific examples of alkynyl groups having 2 to 6 carbon atoms, preferably 2 to 4, in R1 to R4 include: ethynyl, 1-propynyl, 2-propynyl, etc.

[0074] Examples of monovalent organic groups containing fluorine atoms in R1 to R4, with 1 to 6 carbon atoms (preferably 1 to 4), include: fluoromethyl, trifluoromethyl, trifluoromethoxy, 2,2,2-trifluoroethyl, 2,2,2-trifluoroethoxy, pentafluoroethyl, pentafluoropropyl, etc.

[0075] With regard to the above formula (x-1), the group is preferably selected from the group consisting of the following formulas (x1-1) to (x1-5).

[0076]

[0077] From the viewpoint of obtaining the appropriate effects of the present invention, the structural unit (a-1Ta) of the polyamic acid (A) of the present invention is preferably 60 mol% or more, more preferably 70 mol% or more, and most preferably 100 mol% per mole of all structural units derived from tetracarboxylic acid derivatives of the polyamic acid (A).

[0078] The polyamic acid (A) of the present invention may also have the following formula (2T) a The structural unit (a-2Ta) shown is a structural unit derived from a tetracarboxylic acid derivative. The structural unit (2-1Ta) can be one or more of the same type.

[0079]

[0080] (where X) 2a This refers to tetravalent organic groups derived from tetracarboxylic dianhydrides, other than the tetravalent organic group shown in formula (x-1) above.

[0081] As in the above equation (2T) a X in ) 2a Specific examples of tetravalent organic groups include: tetravalent organic groups with alicyclic structures of five or more members (T...). 5a It is a tetravalent organic group obtained by removing two anhydride groups from the following tetracarboxylic dianhydrides (hereinafter, they are also collectively referred to as "other tetracarboxylic dianhydrides").

[0082] 1,2,3,4-Butanetetracarboxylic dianhydride or acyclic aliphatic tetracarboxylic dianhydrides such as those shown in formulas (AL-1) to (AL-7); alicyclic tetracarboxylic dianhydrides such as 1,2,3,4-cyclobutanetetracarboxylic dianhydride (excluding those with a tetravalent organic group (T)). 5a (Tetracarboxylic acid dianhydride); pyromellitic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic acid dianhydride, 3,3',4,4'-diphenyl sulfone tetracarboxylic acid dianhydride, 1,4,5,8-naphthalene tetracarboxylic acid dianhydride, 2,3,6,7-naphthalene tetracarboxylic acid dianhydride, 3,3',4,4'-diphenyl ether tetracarboxylic acid dianhydride, 3,3',4,4'-perfluoroisopropylidene di(phthalic anhydride), 3,3',4,4'-biphenyl tetracarboxylic acid dianhydride, 2,2',3,3'-biphenyl tetracarboxylic acid dianhydride, 4, Aromatic tetracarboxylic acid dianhydrides such as 4'-bis(3,4-dicarboxyphenoxy)-2,2-diphenylpropane dianhydride, ethylene glycol bis(triphenylene) anhydride, 4,4'-(hexafluoroisopropylidene)diphthalic anhydride, 4,4'-carbonyldiphthalic anhydride, 4,4'-oxobis(1,4-phenylene)bis(phthalic acid) dianhydride or 4,4'-methylenebis(1,4-phenylene)bis(phthalic acid) dianhydride; and tetracarboxylic acid dianhydrides as described in Japanese Patent Application Publication No. 2010-97188.

[0083]

[0084] As more preferred examples of the other tetracarboxylic dianhydrides mentioned above, the following can be listed: 1,2,3,4-butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 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'-diphenyl ethertetracarboxylic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, and 2,2',3,3'-biphenyltetracarboxylic dianhydride.

[0085] As the aforementioned tetravalent organic group (T) 5a Preferably, the alicyclic organic group has a five- to eight-membered ring structure, and more preferably, a five- to seven-membered ring structure. It should be noted that an alicyclic structure with five or more members refers to a polycyclic structure in which each ring contains five or more atoms. Furthermore, the alicyclic structure only needs to be bonded to at least one of the two anhydride groups, and may also have an alicyclic structure, a chain hydrocarbon structure, or an aromatic ring structure.

[0086] As a tetravalent organic group (T 5a Specific examples of preferred options for ) can be listed as follows (X) 5a-1) ~ (X) 5a -18) represents any tetravalent organic group. From the viewpoint of properly obtaining the effects of the present invention, the tetravalent organic group (T 5a More preferably (X) 5a -1) ~ (X) 5a -4).

[0087]

[0088] Polyamic acid (A) has the formula (2T) a The proportion of the structural units shown in the diagram is preferably 40 mol% or less, more preferably 30 mol% or less, relative to all structural units derived from tetracarboxylic acid derivatives of polyamic acid (A) per mole.

[0089] Details of the diamine-derived structural units of polyamic acid (A) will be described later.

[0090] <Polyamic acid (B)>

[0091] (The structural units of polyamic acid (B) derived from tetracarboxylic acid derivatives)

[0092] The liquid crystal alignment agent of the present invention comprises the above-described polyamic acid (A) and polyamic acid (B), wherein the polyamic acid (B) has structural units derived from tetracarboxylic acid derivatives and structural units derived from diamines, wherein the structural units derived from tetracarboxylic acid derivatives include the above-described formula (1T). b The structural unit (b-1Tb) is shown in the figure.

[0093] Polyamic acid (B) can be composed of one or more of the above-mentioned structural units constituting polyamic acid (B).

[0094] As provided by the above formula (1T) b X b Examples of tetravalent organic groups include: tetravalent organic groups obtained by removing two anhydride groups (-C(=O)-O-C(=O)-) from aromatic tetracarboxylic dianhydrides; tetravalent organic groups obtained by removing two anhydride groups from 1,2,3,4-cyclobutanetetracarboxylic dianhydrides; and tetravalent organic groups obtained from having the above-mentioned tetravalent organic groups (T 5a A tetravalent organic group is formed by removing two anhydride groups from a tetracarboxylic acid dianhydride.

[0095] Here, the aromatic tetracarboxylic acid dianhydride is obtained by intramolecular dehydration of four carboxyl groups, including at least one carboxyl group bonded to the aromatic ring.

[0096] From the viewpoint of properly obtaining the effects of the present invention, the above-described X bThe tetravalent organic group derived from aromatic tetracarboxylic dianhydrides is preferably a tetracarboxylic dianhydride with a benzene ring. More preferably, X b The tetravalent organic group derived from the aromatic tetracarboxylic acid dianhydride in the formula (2T) is as shown above. a X in ) 2a The example shown is a tetravalent organic group obtained by removing two anhydride groups from an aromatic tetracarboxylic acid dianhydride.

[0097] From the viewpoint of obtaining the appropriate effects of the present invention, polyamic acid (B) preferably contains more than 40 mol% of structural units (b-1Tb) relative to 1 mole of all structural units derived from tetracarboxylic acid derivatives contained in polyamic acid (B), and more preferably contains more than 50 mol% of structural units (b-1Tb).

[0098] The polyamic acid (B) of the present invention may also have the following formula (2T) b The structural unit (b-2Tb) shown is a structural unit derived from a tetracarboxylic acid derivative.

[0099]

[0100] (where X) 2b X represents b (Other tetravalent organic groups.)

[0101] As in the above equation (2T) b X in ) 2b Specific examples of tetravalent organic groups include: tetravalent organic groups obtained by removing two anhydride groups from a non-cyclic aliphatic tetracarboxylic dianhydride; tetravalent organic groups other than those shown in formula (X-2) above; and the aforementioned tetravalent organic groups (T... 5a Other than tetravalent organic groups, and these tetravalent organic groups are formed by removing two anhydride groups from alicyclic tetracarboxylic dianhydrides.

[0102] Here, the acyclic aliphatic tetracarboxylic dianhydride is obtained by intramolecular dehydration of the four carboxyl groups bonded to the chain hydrocarbon structure. It is not necessary for the structure to consist solely of a chain hydrocarbon; a portion of it may also have an alicyclic or aromatic ring structure.

[0103] Alicyclic tetracarboxylic dianhydrides are acidic dianhydrides obtained by intramolecular dehydration of four carboxyl groups, including at least one carboxyl group bonded to the alicyclic structure. None of these four carboxyl groups are bonded to an aromatic ring. Furthermore, it is not necessary for the structure to consist solely of an alicyclic structure; it can also have a chain hydrocarbon structure or an aromatic ring structure in a portion thereof.

[0104] From the viewpoint of properly obtaining the effects of the present invention, the above-described X 2bThe tetravalent organic group is preferably a tetravalent organic group obtained by removing two anhydride groups from a tetracarboxylic dianhydride having at least one partial structure selected from the group consisting of substituted cyclobutane ring structures and cyclobutene ring structures, or a tetravalent organic group obtained by removing two anhydride groups from the non-cyclic aliphatic tetracarboxylic dianhydrides exemplified above.

[0105] More preferred X 2b Examples of tetravalent organic groups can be listed, such as those shown in formula (x-1) above, or tetravalent organic groups obtained by removing two anhydride groups from the non-cyclic aliphatic tetracarboxylic dianhydrides exemplified above.

[0106] From the viewpoint of obtaining the appropriate effects of the present invention, polyamic acid (B) preferably contains less than 60 mol% of structural units (b-2Tb) relative to 1 mole of all structural units derived from tetracarboxylic acid derivatives contained in polyamic acid (B), and more preferably contains less than 50 mol% of structural units (b-2Tb).

[0107] Details of the diamine-derived structural units of polyamic acid (B) will be described later.

[0108] (The diamine-derived structural units of polyamic acid (A) and polyamic acid (B))

[0109] The polyamic acid (A) in the polymer (A) of the present invention has the above formula (1D) a The structural unit (a-1Da) shown is a structural unit derived from diamine. The structural unit (a-1Da) can be one or more types.

[0110] As the above equation (1D) a The monovalent organic group Z in ) can be listed as: a monovalent hydrocarbon group having 1 to 6 carbon atoms; the methylene group of the hydrocarbon group is surrounded by -O-, -S-, -CO-, -COO-, -COS-, -NR-. 3 -、-CO-NR 3 -, -Si(R) 3 )2-(where R 3 It is a monovalent hydrocarbon group consisting of 1 to 6 hydrogen atoms or carbon atoms. In R 3 In the case of two, R 3 Monovalent groups A formed by substitution of the same or different groups (electively identical or different from each other), -SO2-, etc.; monovalent groups formed by substitution of at least one hydrogen atom bonded to the carbon atom of the above-mentioned monovalent hydrocarbon group or the above-mentioned monovalent group A with a halogen atom, hydroxyl group, alkoxy group, nitro group, amino group, mercapto group, nitroso group, alkylsilyl group, alkoxysilyl group, silanol group, sulfinyl group, phospho group, carboxyl group, cyano group, sulfonyl group, acyl group, etc.; monovalent groups having heterocyclic rings.

[0111] As the above equation (1D) a The Z in the form of a monovalent organic group is preferably an alkyl group with 1 to 6 carbon atoms, an alkenyl group with 2 to 6 carbon atoms, an alkynyl group with 2 to 6 carbon atoms, or a tert-butoxycarbonyl group, more preferably an alkyl group with 1 to 3 carbon atoms, and even more preferably a methyl group.

[0112] From the viewpoint of properly obtaining the effects of the present invention, the above formula (1D) a The two Zs in ) are each preferably hydrogen atoms or alkyl groups having 1 to 3 carbon atoms, more preferably hydrogen atoms or methyl groups.

[0113] The polyamic acid (B) in the polymer (B) of the present invention has the above formula (1D) b The structural unit (b-1Db) shown above is a structural unit derived from diamine. The structural unit (b-1Db) can be one or more types. b The monovalent organic group of Z in ) and the above formula (1D) a The meaning of Z is the same as that of ).

[0114] As structural units of the aforementioned structural units (a-1Da) and (b-1Db), the following structural units (1D-1) can be listed: structural units derived from the following diamines, wherein the diamine is selected from diamine (0) "H-N(Z)-Ar1-L1-A-L 1’ -Ar 1’ -N(Z)-H”, diamine (Ph)”H-N(Z)-Ar-N(Z)-H” and diamine (O)'”H-N(Z)-Ar2-L2-A2-L 2’ -Ar 2’ The structural unit (1D-2) of the diamine group represented by -N(Z)-H”; or derived from diamines other than the diamine (0), diamine (Ph) and diamine (0)' (hereinafter also referred to as other diamines), wherein the structural unit (1D-1) is more preferred.

[0115] Here, Ar1, Ar 1’ Each can independently represent a benzene ring, biphenyl structure, or naphthalene ring. Ar1, Ar 1’ Any hydrogen atom on the ring may be optionally replaced by a monovalent group. A represents a divalent organic group with 1 to 10 carbon atoms having an alkylene structure.

[0116] L1, L 1’ Each can independently represent a single bond, -O-, -S-, -C(=O)-, -O-C(=O)-, -NR- (R represents a hydrogen atom or a monovalent organic group), -C(=O)-NR- (R represents a hydrogen atom or a monovalent organic group), or -NR-C(=O)- (R represents a hydrogen atom or a monovalent organic group).

[0117] (Diamine(0))

[0118] L1 and L2, representing the aforementioned diamine (0), 1’ The monovalent organic group R in -NR-, -C(=O)-NR- or -NR-C(=O)- can be listed as: alkyl with 1 to 3 carbon atoms, alkoxy with 1 to 3 carbon atoms, alkenyl with 2 to 3 carbon atoms, acyl with 2 to 3 carbon atoms, alkylsilyl with 1 to 3 carbon atoms, alkoxysilyl with 1 to 3 carbon atoms, Boc group, or a monovalent organic group in which at least a portion of the hydrogen atoms of these groups are replaced by at least any one of a halogen atom and a hydroxyl group.

[0119] Ar1 and Ar2, which are the diamines (0) mentioned above 1’ For monovalent groups substituting any hydrogen atom on the ring, examples include: halogen atoms; alkyl groups having 1 to 3 carbon atoms; alkyl groups having 1 to 3 carbon atoms formed by replacing at least a portion of the hydrogen atoms with halogen atoms or hydroxyl groups; alkoxy groups having 1 to 3 carbon atoms formed by replacing at least a portion of the hydrogen atoms with at least any of the aforementioned halogen atoms and hydroxyl groups; alkenyl groups having 2 to 3 carbon atoms; acyl groups having 2 to 3 carbon atoms; alkylsilyl groups having 1 to 3 carbon atoms; alkoxysilyl groups having 1 to 3 carbon atoms; and monovalent groups such as hydroxyl and nitrile groups.

[0120] Ar1 and Ar, as the aforementioned diamine (0), 1’Specific examples 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-tert-butyl-1,4-phenylene, 2-methoxy-1,4-phenylene, 2-ethoxy-1,4-phenylene, 2-propoxy-1,4-phenylene, 2-butoxy-1,4-phenylene, 2-Fluoro-1,4-phenylene, 2,3-dimethyl-1,4-phenylene, 4-methyl-1,3-phenylene, 5-methyl-1,3-phenylene, 4-fluoro-1,3-phenylene, 2,3,5,6-tetramethyl-1,4-phenylene, etc., optionally having substituted benzene rings; 4,4'-biphenylene, 2-methyl-4,4'-biphenylene, 2-ethyl-4,4'-biphenylene, 2-propyl-4,4'-biphenylene, 2-butyl-4,4'-biphenylene, etc. Biphenylene, 2-tert-butyl-4,4'-biphenylene, 2-methoxy-4,4'-biphenylene, 2-ethoxy-4,4'-biphenylene, 2-fluoro-4,4'-biphenylene, 3-methyl-4,4'-biphenylene, 3-ethyl-4,4'-biphenylene, 3-propyl-4,4'-biphenylene, 3-butyl-4,4'-biphenylene, 3-tert-butyl-4,4'-biphenylene, 3-methoxy-4,4'-biphenylene, 3-ethoxy Biphenyl structures optionally having substituents, such as methyl-4,4'-biphenylene, 3-fluoro-4,4'-biphenylene, 2,2'-dimethyl-4,4'-biphenylene, 3,3'-dimethyl-4,4'-biphenylene, 3,3'-biphenylene, 5-methyl-3,3'-biphenylene, 5,5'-dimethyl-3,3'-biphenylene; and naphthalene rings optionally having substituents, such as 1,5-naphthylene, 2,6-naphthylene, and 1-methyl-2,6-naphthylene.

[0121] In the above-mentioned diamine (0), A is a divalent organic group having 1 to 10 carbon atoms in an alkylene structure. When the alkylene structure has three or more carbon-carbon bonds, any carbon-carbon bond constituting the alkylene structure may be optionally replaced by a carbon-carbon double bond. A is preferably an alkylene group having 1 to 10 carbon atoms (q0); a divalent organic group formed by inserting -O-, -C(=O)-, -NH-, -O-C(=O)-, -C(=O)-O-, -NR-C(=O)-, -C(=O)-NR- or -NR- (R represents a monovalent organic group) between the carbon-carbon bonds of the alkylene group (q1); or a divalent organic group 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 (q2).

[0122] Here, as the monovalent organic group of R in the above-mentioned -NR-C(=O)-NR-, examples can be listed regarding L1 and L, which represent the above-mentioned diamine (0). 1’ The structure exemplified by R in -C(=O)-NR-.

[0123] Specific examples of the preferred options (q0), (q1), and (q2) are described below.

[0124] *-(CH2) n -*、*-(CH2) n1 -O-(CH2) n2 -*、*-(CH2) n1 -NR-(CH2) n2 -*、*-(CH2) m1 -O-C(=O)-(CH2) n’ -C(=O)-O-(CH2) m2 -*、*-(CH2) m1 -C(=O)-O-(CH2) n’ -O-C(=O)-(CH2) m2 -*、*-(CH2) m1 -C(=O)-NR-(CH2) n’ -NR-C(=O)-(CH2) m2 -*、*-(CH2) m1 -NR-C(=O)-(CH2) n’ -C(=O)-NR-(CH2) m2 -*、*-(CH2) n1 -NR-C (=O) -NR- (CH2) n2 -*.

[0125] In the above chemical formula, R represents a hydrogen atom or a monovalent organic group. Examples of such monovalent organic groups include L1 and L2, which represent the diamine (0) described above. 1’ The structure illustrated by R in -C(=O)-NR-. The two Rs may be identical or different from each other.

[0126] n is an integer from 1 to 10, more preferably an integer from 2 to 10, and even more preferably an integer from 2 to 6.

[0127] m1 and m2 are each independent integers from 0 to 4, n' is an integer from 1 to 6, and the sum of m1, m2 and n' is from 1 to 8.

[0128] *-(CH2) n1 -O-(CH2) n2In the given information, n1 and n2 are each an integer from 1 to 6, and the sum of n1 and n2 is from 2 to 10.

[0129] *-(CH2) n1 -NR-C (=O) -NR- (CH2) n2 In the given information, n1 and n2 are each an integer from 1 to 6, and the sum of n1 and n2 is from 2 to 9.

[0130] From the viewpoint of properly obtaining the effects of the present invention, *-L1-A-L 1’ -*The following scheme is preferred. The definitions of m1, m2, n, n', n1, and n2 in the following formulas are the same as those in the formulas above. Furthermore, R in the following formulas represents a hydrogen atom or a monovalent organic group. In the case of two Rs, each has the above definition independently. As the above monovalent organic group, L1 and L2 representing the above diamine (0) formula (H1) can be listed. 1’ The structure exemplified by R in -C(=O)-NR-.

[0131] *-(CH2) n -*、-O-(CH2) n -O-*、*-NR-(CH2) n -NR-*、*-O-(CH2) n1 -O-(CH2) n2 -O-*、*-O-(CH2) n1 -NR-(CH2) n2 -O-*,*-C(=O)-(CH2) n -C(=O)-*,*-C(=O)-NR-(CH2) n -O-*, *-O-C (=O)-(CH2) n -O-*, *-O-C (=O)-(CH2) n -O-C (=O)-*, *-O-C (=O)-(CH2) n -C (=O) -O-*, *- (CH2) m1 -O-C(=O)-(CH2) n’ -C(=O)-O-(CH2) m2 -*、*-S-(CH2) n -S-*,*-C(=O)-NR-(CH2) n -NR-C(=O)-*,*-C(=O)-O-(CH2) n -O-C (=O)-*, *- (CH2) m1 -C(=O)-O-(CH2) n’ -O-C(=O)-(CH2)m2 -*、*-O-(CH2) n -*、*-S-(CH2) n -*,*-NR-C(=O)-(CH2) n -C (=O)-NR-*, *-(CH2) m1 -C(=O)-NR-(CH2) n’ -NR-C(=O)-(CH2) m2 -*、*-(CH2) m1 -NR-C(=O)-(CH2) n’ -C(=O)-NR-(CH2) m2 -*、*-(CH2) n1 -NR-C (=O) -NR- (CH2) n2 -*.

[0132] Furthermore, from the viewpoint of properly obtaining the effects of the present invention, *-(CH2) is preferred. n -*、*-O-(CH2) n -O-*、*-O-(CH2) n -*.

[0133] Polyamic acid (A) may also contain at least one Y a For divalent organic groups having three or more benzene rings, the above formula (1D) a The structural unit shown is a structural unit derived from diamine.

[0134] Here, the benzene ring in "divalent organic groups having three or more benzene rings" also includes the benzene ring that forms a condensation ring. Furthermore, when counting the number of benzene rings in the above-mentioned diamine (0), the naphthalene ring is counted as having two benzene rings, the anthracene ring is counted as having three benzene rings, and the biphenyl structure is counted as having two benzene rings.

[0135] From the viewpoint of achieving the desired effects of the present invention, polyamic acid (A) preferably has the formula (1D) a The structural unit shown in equation (1D) a ), Y a At least one of them is derived from Ar1 and Ar 1’ For diamines (0) with the same structure, the other Y groups are divalent organic groups. a At least one of them is derived from Ar1 and Ar 1’ These are divalent organic groups of diamines (0) with different structures.

[0136] As Ar1 and Ar 1’Preferred combinations of structures with the same characteristics include: combinations of biphenyl structures optionally having the aforementioned substituents and biphenyl structures optionally having the aforementioned substituents, and combinations of naphthalene rings optionally having the aforementioned substituents and naphthalene rings optionally having the aforementioned substituents. Furthermore, as Ar1 and Ar... 1’ Preferred combinations of different structures include: combinations of a benzene ring optionally having the above-mentioned substituents and a biphenyl structure optionally having the above-mentioned substituents; combinations of a benzene ring optionally having the above-mentioned substituents and a naphthalene ring optionally having the above-mentioned substituents; and combinations of a biphenyl structure optionally having the above-mentioned substituents and a naphthalene ring optionally having the above-mentioned substituents.

[0137] From the viewpoint of achieving the appropriate effects of the present invention, the above-described structural unit (1D-1) preferably has a divalent organic group represented by any of the following formulas (h1-1) to (h1-22) or from the formula (d) described later. Da The divalent organic group obtained by removing two amino groups from the diamine shown in (Am-1) and the divalent organic group obtained by removing two amino groups from the diamines shown in (Am-1) to (Am-2) described later.

[0138] In formulas (h1-1) to (h1-22), the bonding positions of the benzene ring are preferably at positions 1 and 4, and the bonding positions of the naphthalene ring are preferably at positions 2 and 6.

[0139] In equation (h1-4), the total number of -CH2- is less than 10.

[0140] In equations (h1-7), (h1-8), and (h1-14), the total number of -CH2- is 8 or less, and the two m can be either the same or different from each other.

[0141] It should be noted that the hydrogen atoms on the benzene ring in the following formulas (h1-1) to (h1-22) may optionally be replaced by methyl, methoxy, or fluorine atoms.

[0142]

[0143]

[0144] (Diamine (Ph))

[0145] Ar represents a benzene ring, a biphenyl structure, a naphthyl ring, or a divalent organic group as shown in the following formula (Im). Any hydrogen atom on the benzene ring, biphenyl structure, or naphthyl ring of Ar is optionally replaced by a monovalent group, which may include: a halogen atom; an alkyl group having 1 to 3 carbon atoms; an alkyl group having 1 to 3 carbon atoms formed by replacing at least a portion of the hydrogen atoms with a halogen atom or a hydroxyl group; an alkoxy group having 1 to 3 carbon atoms formed by replacing at least a portion of the hydrogen atoms with at least any one of the aforementioned halogen atom and hydroxyl group; an alkenyl group having 2 to 3 carbon atoms; an acyl group having 2 to 3 carbon atoms; an alkylsilyl group having 1 to 3 carbon atoms; an alkoxysilyl group having 1 to 3 carbon atoms; a hydroxyl group; a nitrile group, etc.

[0146]

[0147] (In formula (Im), X represents a tetravalent organic group obtained by removing two anhydride groups from an acyclic or alicyclic tetracarboxylic dianhydride.)

[0148] In the above formula (Im), X is preferably in the above formula (x-1) or the above formula (X). 5a -1) ~ (X) 5a -4) The tetravalent organic group shown is a tetravalent organic group obtained by removing two anhydride groups from 1,2,3,4-butanetetracarboxylic acid dianhydride.

[0149] The divalent organic group represented by the above formula (Im) preferably has the structure shown in the following formulas (Im-1) to (Im-6).

[0150]

[0151] Preferred specific examples of diamines (Ph) include: p-phenylenediamine, 2,3,5,6-tetramethylp-phenylenediamine, 2,5-dimethylp-phenylenediamine, m-phenylenediamine, 2,4-dimethylm-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-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, or diamines formed by bonding amino groups to both ends of a divalent organic group as shown in the above formula (Im).

[0152] (diamine(0)')

[0153] Diamine (0)' is "H-N(Z)-Ar2-L2-A2-L" 2’ -Ar 2’ The diamine represented by "-N(Z)-H".

[0154] Ar2 and Ar 2’ Each can independently represent a benzene ring, biphenyl structure, naphthalene ring, or aromatic heterocycle. Ar2 and Ar 2’ Any hydrogen atom on the ring is optionally replaced by a monovalent group. A2 represents a divalent organic group having an alkylene group. A2 is preferably a divalent organic group having 1 to 30 carbon atoms, more preferably a divalent organic group having 1 to 20 carbon atoms, and even more preferably a divalent organic group having 1 to 18 carbon atoms.

[0155] L2, L 2’ Each can independently represent a single bond, -O-, -S-, -C(=O)-, -O-C(=O)-, -NR- (R represents a hydrogen atom or a monovalent organic group), -C(=O)-NR- (R represents a hydrogen atom or a monovalent organic group), or -NR-C(=O)- (R represents a hydrogen atom or a monovalent organic group).

[0156] Among them, Ar2 and Ar 2’Any of the elements in A2 has a heterocyclic ring.

[0157] Examples of heterocycles mentioned above include: pyrrole rings, imidazole rings, pyrazole rings, triazole rings, pyridine rings, pyrimidine rings, pyridazine rings, pyrazine rings, indole rings, benzimidazole rings, purine rings, quinoline rings, isoquinoline rings, naphthidine rings, quinoxaline rings, phthalazine rings, triazine rings, carbazole rings, acridine rings, piperidine rings, piperazine rings, pyrrolidine rings, and hexamethyleneimine rings. Among these, pyridine rings, pyrimidine rings, pyrazine rings, benzimidazole rings, piperidine rings, piperazine rings, quinoline rings, carbazole rings, or acridine rings are preferred.

[0158] As a more preferred specific example of diamine (0)', the following (d Da -8) the diamine shown, 4-[4-[(4-aminophenoxy)methyl]-4,5-dihydro-4-methyl-2-oxazolyl]-aniline, 4-[4-[(4-aminophenoxy)methyl]-4,5-dihydro-2-oxazolyl]-aniline or the following (d Ht -1) ~ (d) Ht -8) represents the diamine. d Ht -6, d Ht -8 is preferably 1,4-bis(p-aminobenzyl)piperazine or 4,4'-[4,4'-propane-1,3-dimethylbis(piperidine-1,4-dimethyl)]diphenylamine.

[0159]

[0160] In one embodiment, in polyamic acid (A) and / or polyamic acid (B), 1 mole of all diamine-derived structural units of polyamic acid (A) and / or polyamic acid (B) preferably contains 5 to 100 mol% of the aforementioned structural units (1D-1), more preferably 5 to 95 mol% of the aforementioned structural units (1D-1), even more preferably 10 to 95 mol% of the aforementioned structural units (1D-1), and even more preferably 20 to 80 mol% of the aforementioned structural units (1D-1).

[0161] Examples of other diamines derived from the structural unit (1D-2) of the other diamines mentioned above include the following diamines.

[0162] 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, a semi-aromatic diamine refers to a diamine in which one amino group is bonded to an aromatic ring and the other amino group is not bonded to an aromatic ring), 4-(2-aminoethyl)aniline, 2-(6-aminonaphthyl)ethylamine and other specific diamines (hereinafter also referred to as specific diamines (1)).

[0163] 1,4-Phenylidene bis(4-aminobenzoate), 1,4-Phenylidene bis(3-aminobenzoate), 1,3-Phenylidene bis(4-aminobenzoate), 1,3-Phenylidene bis(3-aminobenzoate), bis(4-aminophenyl) terephthalate, bis(3-aminophenyl) terephthalate, bis(4-aminophenyl) isophthalate, bis(3-aminophenyl) isophthalate; 4,4'-Diaminoazobenzene, diaminodiphenylacetylene, and others. The diamines, 4,4-diaminochalcones, or [4-[(E)-3-[2-(2,4-diaminophenyl)ethoxy]-3-oxo-prop-1-enyl]phenyl]4-(4,4,4-trifluorobutoxy)benzoate esters represented by formulas (D-1) to (D-5), or [4-[(E)-3-[[5-amino-2-[4-amino-2-[[(E)-3-[4-[4-(4,4,4-trifluorobutoxy)benzoyl]oxyphenyl]prop-2- [-Octoyl]oxymethyl]phenyl]phenyl]methoxy]-3-oxo-prop-1-enyl]phenyl]4-(4,4,4-trifluorobutoxy)benzoate, representing aromatic diamines with cinnamic acid ester structures, and other diamines with photo-oriented groups; diamines with photopolymerizable groups at the ends, such as 2-(2,4-diaminophenoxy)ethyl methacrylate or 2,4-diamino-N,N-diallyl aniline; 1-(4-(2-(2,4-diaminophenoxy) Diamines with free radical polymerization initiator functions, such as ethoxyphenyl)-2-hydroxy-2-methylpropionyl ketone and 2-(4-(2-hydroxy-2-methylpropionyl)phenoxy)ethyl-3,5-diaminobenzoate; diamines with amide bonds, such as 4,4'-diaminobenzoylaniline, diamines represented by formula (D-6) below, and diamines represented by formulas (Am-3) to (Am-6) below; diamines with urea bonds, such as 1,3-bis(4-aminophenyl)urea; H2N-Y D -NH2(Y D Diamines are diamines with thermally detachable groups, such as divalent organic groups (where D represents a protecting group that is removed and replaced by a hydrogen atom upon heating).

[0164] 3,3'-Diaminodiphenyl ether, 3,4'-Diaminodiphenyl ether, 4,4'-Diaminodiphenyl ether, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(4-aminophenoxy)diphenyl ether, 1,4-bis[4-(4-aminophenoxy)phenoxy]benzene, 3,3'-Diaminodiphenylmethane, 3,4'-Diaminodiphenylmethane, 4,4'-Diaminodiphenylmethane, 4,4'-sulfonyldiphenylamine, 3,3'-sulfonyldiphenylamine, bis(4-aminophenyl)silane, bis(3-aminophenyl)silane, dimethyl-bis(4-aminophenyl)silane, dimethyl-bis(3-aminophenyl)silane Silane, 4,4'-thiodiphenylamine, 3,3'-thiodiphenylamine, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 2,2'-bis[4-(4-aminophenoxy)phenyl]propane, 2,2'-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2'-bis(4-aminophenyl)hexafluoropropane, 2,2'-bis(3-aminophenyl)hexafluoropropane, 2,2'-bis(3-amino-4-methylphenyl)hexafluoropropane, 2,2'-bis(4-aminophenyl)propane, 2,2'-bis(3-aminophenyl)propane, 2,2'-bis(3-amino-4-methylphenyl)propane, 4,4'-diaminobenzophenone, 1,4-bis(4-aminobenzyl)benzene;2,6-Diaminopyridine, 3,4-Diaminopyridine, 2,4-Diaminopyrimidine, 3,6-Diaminocarbazole, N-methyl-3,6-diaminocarbazole, 1,4-bis-(4-aminophenyl)-piperazine, 3,6-Diaminoacridine, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, N-(3-(1H-imidazol-1-yl)propyl-3,5-diaminobenzamide, 2,5-bis(4-diaminopyridine)-piperazine, 3,6-diaminoacridine, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, N-(3-(1H-imidazol-1-yl)propyl-3,5-diaminobenzamide, 2,5-bis(4-diaminopyridine)-piperazine, 3,4-diaminopyridine, 2,4-diaminopyridine, 3,6-diaminocarbazole, N-methyl- ... 1,4'-(1-aminophenyl)pyrrole, 4,4'-(1-methyl-1H-pyrrole-2,5-diyl)bis[aniline], 1,4-bis-(4-aminophenyl)piperazine, 2-N-(4-aminophenyl)pyridine-2,5-diamine, 2-N-(5-aminopyridin-2-yl)pyridine-2,5-diamine, 2-(4-aminophenyl)-5-aminobenzimidazole, 2-(4-aminophenyl)-6-aminobenzimidazole, 5-(1H-phenyl)pyrrole-2,5-diamine, 2-(4-aminophenyl)-5-aminobenzimidazole, 2-(4-aminophenyl)-6-aminobenzimidazole, 5-(1H-phenyl)pyrrole-2,5-diamine, 2-(4-aminophenyl)-5-aminobenzimidazole, 2-(4-aminophenyl)-6-aminobenzimidazole, 2 ... The diamines represented by diamines having a diphenylamine structure, such as imidazole-2-yl)phenyl-1,3-diamine or diamines of formulas (z-1) to (z-22) below, are heterocyclic diamines, or diamines with a diphenylamine structure such as 4,4'-diaminodiphenylamine, 4,4'-diaminodiphenyl-N-methylamine, N,N'-bis(4-aminophenyl)-benzidine, N,N'-bis(4-aminophenyl)-N,N'-dimethylbenzidine, or N,N'-bis(4-aminophenyl)-N,N'-dimethyl-1,4-phenylenediamine, have a structure containing at least one nitrogen atom selected from the group consisting of a heterocycle, secondary amino group, or tertiary amino group (excluding amino groups derived from -N(D)- (D represents a protecting group that is removed and substituted with a hydrogen atom by heating). Hereinafter, they are also referred to as specific nitrogen-containing structures. Specific nitrogen-containing structures are diamines containing groups other than the two amino groups involved in the condensation reaction.

[0165] 2,4-Diaminophenol, 3,5-Diaminophenol, 3,5-Diaminobenzyl alcohol, 2,4-Diaminobenzyl alcohol, 4,6-Diaminoresorcinol, 4,4'-Diamino-3,3'-Dihydroxybiphenyl; 2,4-Diaminobenzoic acid, 2,5-Diaminobenzoic acid, 3,5-Diaminobenzoic acid, 4,4'-Diaminobiphenyl-3-carboxylic acid, 4,4'-Diaminodiphenylmethane-3-carboxylic acid, 4,4'-Diaminodiphenylethane-3-carboxylic acid, 4,4'-Diaminobiphenyl-3,3'-dicarboxylic acid Acids, 4,4'-diaminobiphenyl-2,2'-dicarboxylic acid, 3,3'-diaminobiphenyl-4,4'-dicarboxylic acid, 3,3'-diaminobiphenyl-2,4'-dicarboxylic acid, 4,4'-diaminodiphenylmethane-3,3'-dicarboxylic acid, 4,4'-diaminodiphenylethane-3,3'-dicarboxylic acid, 4,4'-diaminodiphenyl ether-3,3'-dicarboxylic acid, and other diamines with carboxyl groups; 1-(4-aminophenyl)-1,3,3-trimethyl-1H-inden-5-amine, 1-(4-aminophenyl) Diamines with a steroidal skeleton, such as cholesteryloxy-3,5-diaminobenzene, cholesteryloxy-3,5-diaminobenzene, cholesteryloxy-2,4-diaminobenzene, cholesteryl ester of 3,5-diaminobenzoate, cholesteryl ester of 3,5-diaminobenzoate, cholesteryl ester of 3,5-diaminobenzoate, and lanostane of 3,6-bis(4-aminobenzoyloxy)cholestan; diamines represented by the following formulas (V-1) to (V-2); 1 Diamines containing siloxane bonds, such as 3-bis(3-aminopropyl)-tetramethyldisiloxane; acyclic aliphatic diamines such as m-phenylenediamine, 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 formed by bonding two amino groups to any of the formulas (Y-1) to (Y-167) described in WO2018 / 117239.

[0166]

[0167]

[0168]

[0169]

[0170]

[0171] X in (z-13) 13 (This indicates methyl or phenyl.)

[0172]

[0173] (In formula (z-19), X) 19 Represents -C (=O)-, -O-, or -NH-. R 19 R 19’ Each can be used independently to represent a hydrogen atom or a methyl group.

[0174] In equation (z-22), X 22 It represents -CH2-, -(CH2)3-, or -NH-.

[0175]

[0176] In equation (V-1), m and n are integers from 0 to 3 (where 1 ≤ m + n ≤ 4), j is an integer of 0 or 1, and X 1 It represents - (CH2) a - (a is an integer from 1 to 15), -CONH-, -NHCO-, -CO-N(CH3)-, -NH-, -O-, -CH2O-, -CH2-OCO-, -COO-, or -OCO-. R 1 This refers to a fluorine atom, an alkyl group containing fluorine atoms with 1 to 10 carbon atoms, an alkoxy group containing fluorine atoms with 1 to 10 carbon atoms, an alkyl group with 3 to 10 carbon atoms, an alkoxy group with 3 to 10 carbon atoms, or an alkoxyalkyl group with 3 to 10 carbon atoms. In formula (V-2), X 2 This represents -O-, -CH2O-, -CH2-OCO-, -COO-, or -OCO-. In equations (z-2), (V-1), and (V-2), there exist two m, n, and X. 1 R 1 In the case of each, they each independently possess the above definitions.

[0177] It should be noted that the D in the -N(D)- group of the other diamines mentioned above is preferably an organic group of the carbamate system, such as benzyloxycarbonyl, 9-fluorenyloxycarbonyl, allyloxycarbonyl, or Boc group. From the viewpoint of good efficiency in thermal release, release at relatively low temperatures, and release as a harmless gas during release, the Boc group is particularly preferred.

[0178] Preferred examples of diamines having thermally detachable groups, exemplified as other diamines mentioned above, include those selected from the following formula (d Da -1) ~ (d) Da diamines selected from the following formula (d-10), wherein, more preferably, they are selected from the following formula (d-10). Da -2) ~ (d) Da -7), (d) Da -9) ~ (d Da The diamine in (-10). (wherein, (d) Da-3) ~ (d) Da -5) The total number of carbon atoms in the linking groups connecting the benzene ring is 11 or more.

[0179]

[0180] (Formula (d) Da -2), (d) Da -6), (d) Da In -7), R represents a hydrogen atom or a Boc group.

[0181]

[0182] In one embodiment, where the polyamic acid (A) and / or polyamic acid (B) used in this invention have the above-described structural units (1D-2), from the viewpoint of properly obtaining the effects of this invention, it is more preferable to contain structural units derived from the above-described specific diamine (1).

[0183] The structural unit derived from the specific diamine (1) is preferably 5 to 95 mol% of 1 mole of all the diamine-derived structural units contained in polyamic acid (A) and / or polyamic acid (B), more preferably 5 to 90 mol%, and even more preferably 20 to 80 mol%.

[0184] Furthermore, from the viewpoint of improving the two-phase separability between the two polymers, polyamic acid (A) and / or polyamic acid (B) may also contain structural units derived from the diamine having thermally detachable groups as the aforementioned structural units (1D-2). The structural units derived from the diamine having thermally detachable groups are preferably 5 to 40 mol% per mole of all diamine-derived structural units contained in polyamic acid (A) and / or polyamic acid (B), more preferably 5 to 35 mol%, and even more preferably 5 to 30 mol%.

[0185] Furthermore, from the viewpoint of properly obtaining the effects of the present invention, as for polyamic acid (A) and / or polyamic acid (B), the above-mentioned structural unit (1D-2) is preferably derived from a diamine other than the diamine having a thermally detachable group, which does not have a side chain group having 3 or more carbon atoms.

[0186] Examples of diamines having three or more carbon atoms as side chain groups include: diamines having photo-oriented groups having three or more carbon atoms as side chain groups; diamines having photopolymerizable groups at the ends having three or more carbon atoms as side chain groups; diamines having free radical polymerization initiator functions having three or more carbon atoms as side chain groups; diamines having specific nitrogen-containing structures having three or more carbon atoms as side chain groups; diamines having a steroidal skeleton; and diamines with formulas (V-1) to (V-2) shown above having three or more carbon atoms as side chain groups.

[0187] Regarding polyamic acid (A) and / or polyamic acid (B), from the viewpoint of having fewer residual images originating from residual DC, the above-mentioned Y a and / or Y b Preferably, the divalent organic group is formed by removing two amino groups from the following diamines (also collectively referred to as "specific divalent organic group (b)"), wherein the diamine is selected from diamines having a urea bond (e.g., diamine (0) where A is a divalent organic group (q2) or diamines having a urea bond as exemplified among the other diamines mentioned above), diamines having an amide bond, diamine (Ph), diamine (0)', diamines having a specific nitrogen-containing structure, diamines having a carboxyl group, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, p-phenylenediamine, and m-phenylenediamine.

[0188] From the viewpoint of having fewer residual images originating from residual DC, polyamic acid (A) and / or polyamic acid (B) may contain more than 5 mol% of the aforementioned Y per mole of all diamine-derived structural units of polyamic acid (A) and / or polyamic acid (B). a and / or Y b For the specific divalent organic group (b) mentioned above, the formula (1D) b The structural unit (b-1Db) shown in the diagram preferably contains more than 10 mol% of the structural unit (b-1Db), and more preferably more than 20 mol% of the structural unit (b-1Db).

[0189] Furthermore, from the viewpoint of properly obtaining the effects of the present invention, as for polyamic acid (A) and / or polyamic acid (B), the above-mentioned structural unit (b-1Db) is preferably derived from a diamine other than the diamine having a thermally detachable group, which does not have a side chain group having 3 or more carbon atoms.

[0190] As the above equation (1D) b The monovalent organic group Z in ) can be listed for the above formula (1D) aThe structure illustrated by Z in ).

[0191] As one embodiment of the liquid crystal alignment agent of the present invention, the following embodiments (BL1) to (BL2) can be listed, but are not limited to these.

[0192] Scheme (BL1): In the above-mentioned polyamic acid (A), 1 mole of all structural units derived from diamines in polyamic acid (A) contains 5 to 95 mol% of the above-mentioned structural units (1D-1), and in the polyamic acid (B), 1 mole of all structural units derived from diamines in polyamic acid (B) contains 10 mol% or more of the above-mentioned specific divalent organic groups (b).

[0193] Scheme (BL2): As one scheme of the liquid crystal alignment agent of the present invention, in polyamic acid (A), 1 mole of all structural units derived from diamines in polyamic acid (A) contains 5 to 95 mol% of the above-mentioned structural units (1D-1), in polyamic acid (B), 1 mole of all structural units derived from diamines in polyamic acid (B) contains 10 to 95 mol% of the above-mentioned specific divalent organic groups (b), and 1 mole of all structural units derived from diamines in polyamic acid (B) contains 5 to 90 mol% of the above-mentioned structural units (1D-1) other than the above-mentioned specific divalent organic groups (b).

[0194] In the liquid crystal alignment agent of the present invention, from the viewpoint of the effect of the present invention, and from the viewpoint of having less residual image from residual DC, the content ratio of polyamic acid (A) and polyamic acid (B) in the mass ratio of [polyamic acid (A) / polyamic acid (B)] can be 10 / 90 to 90 / 10, or 20 / 80 to 90 / 10, or 20 / 80 to 80 / 20.

[0195] <Manufacturing of Polyamic Acid>

[0196] The polyamic acid contained in the liquid crystal alignment agent of the present invention can be manufactured, for example, by the following method.

[0197] By reacting a tetracarboxylic dianhydride component, a diamine component, and an amino-terminal modifier added as needed, a polymer (polyamic acid) with an amic acid structure is obtained. The polyamic acid has the above formula (1D...). a In the case of the structure shown, for example as a diamine component, a structure having -N(Z)-Y is used. a -N(Z)- structure (Y a The definition of Z is the same as above. Furthermore, as a tetracarboxylic acid derivative component, a diamine with X is used. a (X) a (The definition is the same as above) Tetracarboxylic acid dianhydride.

[0198] Regarding the ratio of tetracarboxylic dianhydride and diamine used in the manufacture of polyamic acid, the anhydride group of the tetracarboxylic dianhydride is preferably 0.5 to 2 equivalents relative to the amino group of the diamine, more preferably 0.8 to 1.2 equivalents. Similar to conventional polycondensation reactions, the closer the equivalent of the anhydride group of the tetracarboxylic dianhydride is to 1 equivalent, the larger the molecular weight of the resulting polyamic acid.

[0199] The reaction temperature in the manufacture of polyamic acid is preferably -20 to 150°C, more preferably 0 to 100°C. Furthermore, the reaction time is preferably 0.1 to 24 hours, more preferably 0.5 to 12 hours.

[0200] The production of polyamic acid can be carried out at any concentration, preferably 1 to 50% by mass, more preferably 5 to 30% by mass. Alternatively, the reaction can be carried out at a high concentration initially, followed by the addition of solvent.

[0201] At least a portion of the polyamic acid (A) described above has a terminal portion containing the aforementioned non-amino group. At least a portion of the polyamic acid (B) described above may also have a terminal portion containing the aforementioned non-amino group. The non-amino group may be formed, for example, using an amino-terminal modifier.

[0202] Preferred specific examples of amino-terminal modifiers include: the above-mentioned acyclic aliphatic dicarboxylic anhydrides, compounds (e2-1), (e2-2), or active ester compounds (e3).

[0203] The above-mentioned polyamic acid (A) and / or polyamic acid (B) can be obtained, for example, by the following preparation method (a), preparation method (b), or by using both of these methods.

[0204] Preparation method (a): A method for polymerizing (condensing) a tetracarboxylic acid dianhydride component, a diamine component, and an amino-terminal modifier.

[0205] Preparation method (b): After reacting the tetracarboxylic acid dianhydride component with the diamine component to obtain a polymer solution containing polyamic acid that becomes an unmodified amino terminus, an amino terminator is added to the polymer solution to cause the end of the polymer to react.

[0206] In the above preparation method (b), in order to obtain polyamic acid with an amino terminus, the ratio of the tetracarboxylic dianhydride and the diamine used in the production of polyamic acid is such that the ratio of the diamine used is greater than or equal to the ratio of the tetracarboxylic dianhydride used. The anhydride group of the tetracarboxylic dianhydride is preferably 0.5 to 1.0 equivalents relative to the amino group of the diamine, and more preferably 0.8 to 1.0 equivalents.

[0207] The proportion of the amino-terminal modifier used relative to 100 molar parts of the total diamine components used is preferably 40 molar parts or less, more preferably 30 molar parts or less.

[0208] Furthermore, the proportion of the amino-terminal modifier used is preferably 0.1 moles or more, more preferably 0.2 moles or more, relative to the total 100 moles of the diamine component used.

[0209] Regarding the temperature at which the amino-terminated modifier reacts with polyamic acid, it can be the same as the reaction temperature used in the manufacture of polyamic acid, or the reaction can be carried out while heating. The preferred heating temperature is 30–80°C, more preferably 30–60°C. Furthermore, the preferred reaction time is 0.1–24 hours, more preferably 1–24 hours.

[0210] Specific examples of organic solvents used in the manufacture of polyamic acid include: cyclohexanone, cyclopentanone, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, and 1,3-dimethyl-2-imidazolinone. Furthermore, when the solvent used to manufacture the polyamic acid has high solubility, solvents such as methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, diethylene glycol monomethyl ether, or diethylene glycol monoethyl ether can be used.

[0211] <Solution viscosity / molecular weight of polyamic acid>

[0212] Regarding the polyamic acid used in this invention, when preparing it into a solution with a concentration of 10-15% by mass, for example, from an operational point of view, a polyamic acid with a solution viscosity of 10-1000 mPa·s is preferred. It should be noted that the solution viscosity (mPa·s) of the polymer described above is a value measured using an E-type rotational viscometer at 25°C for a polymer solution with a concentration of 10-15% by mass prepared using a good solvent for the polymer (e.g., γ-butyrolactone, N-methyl-2-pyrrolidone, etc.).

[0213] The weight-average molecular weight (Mw) of the polyamic acid, as determined by gel permeation chromatography (GPC) and converted from polystyrene, is preferably 1,000 to 500,000, more preferably 2,000 to 300,000. Furthermore, the molecular weight distribution (Mw / Mn) shown by the ratio of Mw to the number-average molecular weight (Mn) of polystyrene determined by GPC is preferably 15 or less, more preferably 10 or less. Within this molecular weight range, good orientation and stability of the liquid crystal display element can be ensured.

[0214] The liquid crystal alignment agent of the present invention may also contain polymers other than polymer (A) and polymer (B). Specific examples of other polymers include polymers selected from the group consisting of: at least one polymer (Q) selected from the group consisting of polyimide precursors other than polymer (A) and polymer (B) and polyimides that are imide derivatives of the polyimide precursors; polysiloxanes; polyesters; polyamides; polyureas; polyorganosiloxanes; cellulose derivatives; polyacetals; polystyrene derivatives; poly(styrene-maleic anhydride) copolymers; poly(isobutylene-maleic anhydride) copolymers; poly(vinyl ether-maleic anhydride) copolymers; poly(styrene-phenylmaleimide) derivatives; and poly(meth)acrylates. Specific examples of poly(styrene-maleic anhydride) copolymers include SMA1000, SMA2000, SMA3000 (manufactured by Cray Valley), and GSM301 (manufactured by Gifu Shellac Manufacturing). Specific examples of poly(isobutylene-maleic anhydride) copolymers include ISOBAM-600 (manufactured by Kuraray). Specific examples of poly(vinyl ether-maleic anhydride) copolymers include Gantrez AN-139 (methyl vinyl ether maleic anhydride resin, manufactured by Ashland).

[0215] Other polymers may be used alone, or in combination of two or more. The proportion of other polymers relative to 100 parts by weight of the polymer component contained in the liquid crystal alignment agent is preferably 10 to 90 parts by weight, more preferably 20 to 80 parts by weight.

[0216] It should be noted that, in this specification, polymer composition refers to polymer (A), polymer (B), and other polymers contained in the liquid crystal alignment agent. When the liquid crystal alignment agent contains only polymer (A) and polymer (B), polymer composition refers to polymer (A) and polymer (B).

[0217] As another embodiment of the present invention, it includes the liquid crystal alignment agent described below.

[0218] A liquid crystal alignment agent, characterized in that it contains polymer (A) and polymer (B) as described below, and can obtain a liquid crystal alignment film with a rotation angle change of less than 0.2° as shown in Formula 1 below.

[0219] Polymer (A): A polyamic acid (A) having structural units derived from tetracarboxylic acid derivatives and structural units derived from diamines, wherein the structural units derived from tetracarboxylic acid derivatives comprise the following formula (1T) aThe structural unit (a-1Ta) shown in the figure, as a structural unit derived from diamine, contains the following formula (1D). a The structural unit (a-1Da) shown in the above-mentioned polyamic acid (A) has at least a portion of its terminal containing a non-amino group, which is a functional group shown in the following structural formula (E).

[0220] Polymer (B): Polyamic acid (B) having structural units derived from tetracarboxylic acid derivatives and structural units derived from diamines, wherein the structural units derived from tetracarboxylic acid derivatives comprise the following formula (1T) b The structural unit (b-1Tb) shown, as a structural unit derived from diamine, contains the following formula (1D). b The structural unit (b-1Db) is shown in the figure.

[0221]

[0222] (where X) a This represents the tetravalent organic group shown in the following formula (x-1). Formula (1D) a ), Y a The radical Z represents a divalent organic group derived from a diamine. Each Z independently represents a hydrogen atom or a monovalent organic group.

[0223]

[0224] (In formula (x-1), R1 to R4 each independently represent a hydrogen atom, a halogen atom, an alkyl group with 1 to 6 carbon atoms, an alkenyl group with 2 to 6 carbon atoms, an alkynyl group with 2 to 6 carbon atoms, a monovalent organic group containing a fluorine atom with 1 to 6 carbon atoms, an alkoxy group with 1 to 6 carbon atoms, an alkoxyalkyl group with 2 to 6 carbon atoms, an alkoxycarbonyl group with 2 to 6 carbon atoms, or a phenyl group. At least one of R1 to R4 represents a group other than a hydrogen atom as defined above. * indicates a bond.)

[0225]

[0226] (where X) b This refers to a tetravalent organic group derived from an aromatic tetracarboxylic acid dianhydride, a tetravalent organic group represented by the following formula (x-2), or a tetravalent organic group with an alicyclic structure having five or more members (T). 5a Equation (1D) b ), Y b This represents a divalent organic group derived from a diamine. Z is related to the above formula (1D). a The meaning of Z is the same as that of )

[0227]

[0228]

[0229] (In formula (E), Q is a monovalent organic group selected from any of the groups (e1) to (e3) listed below. * indicates a bond.)

[0230] (e1) Non-cyclic hydrocarbon groups with 1 to 6 carbon atoms.

[0231] (e2) A monovalent organic group having 1 to 2 carboxyl groups and 2 to 30 carbon atoms (wherein, the monovalent organic group does not contain anhydride groups).

[0232] (e3) A monovalent organic group having two or more Boc atoms, and excluding Boc atoms, having a carbon number of 1 to 30, wherein the monovalent organic group has a protected amino group selected from the group consisting of *1-NH(Boc), *1-N(Boc)2, and "*1-N(Boc)-*1" (*1 represents a bond bonded to a carbon atom). It should be noted that when there are two or more protected amino groups, the protected amino groups may optionally be the same or different.

[0233] [Equation 1]

[0234] Δ=|Δb-Δa|

[0235] Δ: The change in rotation angle after 48 hours of storage at room temperature.

[0236] Δa: Rotation angle of the liquid crystal cell.

[0237] Δb: The rotation angle of the liquid crystal cell using the same liquid crystal alignment agent that has been left at room temperature for 48 hours.

[0238] (In Equation 1 above, the rotation angle is as follows: Two substrates with liquid crystal alignment films are used as a group. A sealant is applied to one substrate, and the other substrate is bonded together with the liquid crystal alignment film surfaces facing each other and the alignment direction being 0°. The sealant is then cured, liquid crystal is injected, and the injection port is sealed to obtain a liquid crystal cell. The obtained liquid crystal cell is lit with a backlight of 15000 nits, and an AC voltage of ±7V is applied at a frequency of 60Hz for 120 hours. The pixel electrode and the counter electrode of the liquid crystal cell are then short-circuited. The cell is left at room temperature for one day. The deviation between the alignment direction of the liquid crystal in the first region of the pixel and the alignment direction of the liquid crystal in the second region of the pixel is calculated for the liquid crystal cell under the condition of no voltage application.)

[0239] The change in rotation angle shown in Equation 1 above is preferably less than 0.12°, and more preferably less than 0.12°.

[0240] The rotation angle of the liquid crystal cell using the liquid crystal alignment agent of another embodiment of the present invention is less than 0.2°, which suppresses the deterioration of liquid crystal alignment caused by room temperature storage.

[0241] It should be noted that, including the preferred embodiment, the meanings of the symbols in the liquid crystal alignment agent of another embodiment of the present invention are the same as the meanings of the symbols in the liquid crystal alignment agent described above.

[0242] <Liquid Crystal Alignment Agent>

[0243] The liquid crystal alignment agent of the present invention is used to manufacture liquid crystal alignment films, and from the viewpoint of forming a uniform thin film, it is adopted in the form of a coating liquid. In the liquid crystal alignment agent of the present invention, a coating liquid containing the aforementioned polymer component and solvent is preferred.

[0244] The content (concentration) of the polymer component contained in the liquid crystal alignment agent of the present invention can also be appropriately changed according to the desired thickness of the coating film. From the perspective of forming a uniform and defect-free coating film, it is preferably 1% by mass or more relative to the total amount of the liquid crystal alignment agent, and from the perspective of the storage stability of the solution, it is preferably 10% by mass or less.

[0245] From the viewpoint of achieving the desired effect of this disclosure, the total proportion of polymer (A) and polymer (B) in the liquid crystal alignment agent is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, and even more preferably 50 parts by mass or more, relative to 100 parts by mass of the total polymers contained in the liquid crystal alignment agent. When the liquid crystal alignment agent contains other polymers, the proportion 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 alignment agent.

[0246] The solvent used in liquid crystal alignment agents is not particularly limited as long as it uniformly dissolves the polymer components. Specific examples include: N,N-dimethylformamide, N,N-dimethylacetamide, N,N-dimethyllactic acid, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethyl sulfoxide, γ-butyrolactone, γ-valerolactone, 1,3-dimethyl-2-imidazolinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, 3-methoxy-N,N-dimethylpropionamide, and 3-butoxy-N,N-dimethylpropionamide. N-n-propyl-2-pyrrolidone, N-isopropyl-2-pyrrolidone, N-n-butyl-2-pyrrolidone, N-tert-butyl-2-pyrrolidone, N-n-pentyl-2-pyrrolidone, N-(3-methoxypropyl)-2-pyrrolidone, N-(2-ethoxyethyl)-2-pyrrolidone, N-(4-methoxybutyl)-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone (also collectively referred to as "good solvents"), etc. Among these, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 3-methoxy-N,N-dimethylpropionamide, 3-butoxy-N,N-dimethylpropionamide, or γ-butyrolactone are preferred. The content of the good solvent is preferably 20-99% by mass of the total solvent contained in the liquid crystal alignment agent, more preferably 20-90% by mass, and particularly preferably 30-80% by mass.

[0247] Furthermore, the solvent contained in the liquid crystal alignment agent is preferably a mixed solvent that, in addition to the solvents mentioned above, also uses a solvent that improves the coatability and surface smoothness of the coating film when applying the liquid crystal alignment agent (also known as a poor solvent). Specific examples of the poor solvents used are described below, but are not limited thereto.

[0248] Examples include: diisopropyl ether, diisobutyl ether, diisobutylmethanol (2,6-dimethyl-4-heptanol), ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, 4-hydroxy-4-methyl-2-pentanone, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, 3-ethoxyacetic acid butyl ester, 1-methylacetic acid pentyl ester, 2-ethylacetic acid butyl ester, 2-ethylacetic acid hexyl ester, ethylene glycol monoacetate, ethylene glycol diacetate, propylene carbonate, ethylene carbonate, ethylene glycol monobutyl ether, ethylene glycol monoisopentyl ether, ethylene glycol monohexyl ether, propylene glycol monobutyl ether, 1-(2-butoxyethoxy)-2-propanol, 2- (2-Butoxyethoxy)-1-propanol, propylene glycol monomethyl ether acetate, propylene glycol diacetate, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 2-(2-ethoxyethoxy)ethyl acetate, diethylene glycol diacetate, n-butyl acetate, propylene glycol monoethyl ether acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, butyl 3-methoxypropionate, n-butyl lactate, isoamyl lactate, diethylene glycol monoethyl ether, diisobutyl ketone (2,6-dimethyl-4-heptanone), etc. The content of the undesirable solvent is preferably 1 to 80% by mass of the total solvent contained in the liquid crystal alignment agent, more preferably 10 to 80% by mass, and particularly preferably 20 to 70% by mass. The type and content of undesirable solvents should be appropriately selected based on the coating equipment, coating conditions, and coating environment of the liquid crystal alignment agent.

[0249] Among them, diisobutylmethanol, propylene glycol monobutyl ether, propylene glycol diacetate, diethylene glycol diethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, or diisobutyl ketone are preferred.

[0250] Preferred combinations of good and bad solvents include: N-methyl-2-pyrrolidone and ethylene glycol monobutyl ether; N-methyl-2-pyrrolidone, γ-butyrolactone, and ethylene glycol monobutyl ether; N-methyl-2-pyrrolidone, γ-butyrolactone, and propylene glycol monobutyl ether; N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether; N-methyl-2-pyrrolidone, γ-butyrolactone, 4-hydroxy-4-methyl-2-pentanone, and diethylene glycol diethyl Ethers; N-methyl-2-pyrrolidone, 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 diisobutylmethanol; N-methyl-2-pyrrolidone, γ-butyrolactone and dipropylene glycol dimethyl ether; N-methyl-2-pyrrolidone, propylene glycol monobutyl ether and dipropylene glycol dimethyl ether, etc.

[0251] The liquid crystal alignment agent of the present invention may also contain additional components (hereinafter also referred to as additive components) other than polymer components and solvents. Examples of such additive components include: compounds for improving the strength of the liquid crystal alignment film (hereinafter also referred to as crosslinking compounds); adhesion promoters for improving the adhesion between the liquid crystal alignment film and the substrate, and the adhesion between the liquid crystal alignment film and the sealant; dielectrics, conductive substances for adjusting the dielectric constant and resistance of the liquid crystal alignment film, or imidization promoters for promoting imidization, etc.

[0252] Examples of such crosslinking compounds include at least one crosslinking compound selected from the group consisting of crosslinking compounds having substituents (c-1) and crosslinking compounds having polymerizable unsaturated groups (c-2), wherein the substituents are selected from at least one of epoxy groups, oxacyclobutane groups, oxazoline structures, cyclic carbonate groups, terminal isocyanate groups, hydroxyl groups, and alkoxy groups.

[0253] The following compounds are examples of preferred crosslinking compounds (c-1) and (c-2) mentioned above.As compounds with epoxy groups, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, dibromonepentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol, bisphenol A type epoxy resins such as EPIKOTE 828 (manufactured by MITSUBISHI CHEMICAL), bisphenol F type epoxy resins such as EPIKOTE 807 (manufactured by MITSUBISHI CHEMICAL), hydrogenated bisphenol A type epoxy resins such as YX-8000 (manufactured by MITSUBISHI CHEMICAL), and YX6954BH30 (manufactured by MITSUBISHI CHEMICAL) are examples. Epoxy resins containing a biphenyl backbone, such as those manufactured by CHEMICAL Corporation; phenolic varnish-type epoxy resins such as EPPN-201 (manufactured by Nippon Kayaku Co., Ltd.); (o-, m-, p-)cresol varnish-type epoxy resins such as EOCN-102S (manufactured by Nippon Kayaku Co., Ltd.); tetra(glycidyloxymethyl)methane; N,N,N',N'-tetraglycidyl-1,4-phenylenediamine; N,N,N',N'-tetraglycidyl-2,2'-dimethyl-4,4'-diaminobiphenyl. Compounds in which tertiary nitrogen atoms are bonded to aromatic carbon atoms, such as 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, Compounds in which tertiary nitrogen atoms are bonded to aliphatic carbon atoms, such as tri(N,N-diglycidylaminomethyl)benzene, 1,3,5-tris(N,N-diglycidylaminomethyl)cyclohexane, and 1,3,5-tris(N,N-diglycidylaminomethyl)benzene; isocyanurate compounds such as TEPIC (manufactured by Nissan Chemical Co., Ltd.); compounds described in paragraph 0037 of Japanese Patent Application Publication No. 10-338880; and compounds described in WO2017 / 170483.

[0254] Compounds having oxetyl groups include 1,4-bis{[(3-ethyl-3-oxetyl)methoxy]methyl}benzene (ARON OXETANE OXT-121 (XDO)), bis[2-(3-oxetyl)butyl] ether (ARON OXETANE OXT-221 (DOX)), 1,4-bis[(3-ethyloxetane-3-yl)methoxy]benzene (HQOX), 1,3-bis[(3-ethyloxetane-3-yl)methoxy]benzene (RSOX), 1,2-bis[(3-ethyloxetane-3-yl)methoxy]benzene (CTOX), and compounds having two or more oxetyl groups as described in paragraphs 0170 to 0175 of WO2011 / 132751.

[0255] Compounds having an oxazoline structure include 2,2'-bis(2-oxazoline), 2,2'-bis(4-methyl-2-oxazoline), etc.; polymers and oligomers with an oxazoline group, such as EPOCROS (trade name, Nippon Shokubai Co., Ltd.); and compounds described in paragraph 0115 of Japanese Patent Application Publication No. 2007-286597.

[0256] Compounds having a cyclic carbonate group include N,N,N',N'-tetratetra[(2-oxo-1,3-dioxolane-4-yl)methyl]-4,4'-diaminodiphenylmethane, N,N'-di[(2-oxo-1,3-dioxolane-4-yl)methyl]-1,3-phenylenediamine, and compounds described in paragraphs 0025 to 0030 and 0032 of WO2011 / 155577.

[0257] Examples of compounds having capped isocyanate groups include commercially available products such as CORONATE AP stable M, CORONATE 2503, 2515, 2507, 2513, 2555, MILLIONATE MS-50 (all manufactured by TOSOH); TAKENATE B-830, B-815N, B-820NSU, B-842N, B-846N, B-870N, B-874N, B-882N (all manufactured by Mitsui Chemicals); compounds shown in formulas (bL-1) to (bL-3); compounds having two or more protected isocyanate groups as described in paragraphs 0046 to 0047 of Japanese Patent Application Publication No. 2014-224978; and compounds having three or more protected isocyanate groups as described in paragraphs 0119 to 0120 of Japanese Patent Application Publication No. WO2015 / 141598.

[0258]

[0259] Compounds having hydroxyl and / or alkoxy groups include N,N,N',N'-tetra(2-hydroxyethyl)hexamethylenediamine, compounds shown in formulas (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 paragraph 0058 of Japanese Patent Application Publication No. WO2015 / 072554, Japanese Patent Application Publication No. 2016-118753, Japanese Patent Application Publication No. 2016-200798, and compounds described in Japanese Patent Application Publication No. WO2010 / 074269.

[0260]

[0261] As crosslinking compounds with polymerizable unsaturated groups, these include mono(meth)acrylates, di(meth)acrylates (a mixture of 1,2- and 1,3-type compounds), tri(meth)acrylates, glycerol 1,3-diglyceryl alcohol 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.

[0262] The above-described compound is an example of a cross-linking compound, but is not limited thereto. Examples include, for instance, components other than those described above, disclosed in paragraphs 0105 on page 53 to 0116 on page 55 of WO2015 / 060357. Furthermore, two or more cross-linking compounds may be combined.

[0263] When using a crosslinking compound, the content of the crosslinking compound in the liquid crystal alignment agent is preferably 0.5 to 20 parts by mass relative to 100 parts by mass of the polymer component contained in the liquid crystal alignment agent, more preferably 1 to 15 parts by mass.

[0264] Examples of such sealing agents include: 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-ureopropyltrimethoxysilane, 3-ureopropyltriethoxysilane, and N-ethoxycarbonyl-3-aminopropyltrimethoxysilane. Methoxysilane, 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-diazanonylacetate, 9-triethoxysilyl-3,6-diazanonylacetate, N-benzyl-3-aminopropyltriethoxysilane N-Benzyl-3-aminopropyltriethoxysilane, N-Phenyl-3-aminopropyltrimethoxysilane, N-Phenyl-3-aminopropyltriethoxysilane, Vinyltrimethoxysilane, Vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-epoxypropoxypropylmethyldimethoxysilane, 3-epoxypropoxypropyltrimethoxysilane, 3-epoxypropoxypropylmethyldiethoxysilane, 3-epoxypropoxypropyltriethoxysilane, p-Benzene Vinyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, tris[3-(trimethoxysilyl)propyl]isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-isocyanopropyltriethoxysilane, and other silane coupling agents.

[0265] When using an adhesive additive, the content of the adhesive additive in the liquid crystal alignment agent is preferably 0.1 to 30 parts by mass relative to 100 parts by mass of the polymer component contained in the liquid crystal alignment agent, more preferably 0.1 to 20 parts by mass.

[0266] Examples of substances that can be used as dielectrics or conductors include monoamines such as 3-aminomethylpyridine, which have nitrogen-containing aromatic heterocycles.

[0267] When using a dielectric or conductive substance, the content of the dielectric or conductive substance in the liquid crystal alignment agent is preferably 0.1 to 30 parts by mass relative to 100 parts by mass of the polymer component contained in the liquid crystal alignment agent, more preferably 0.1 to 20 parts by mass.

[0268] (Liquid crystal alignment film)

[0269] The liquid crystal alignment film of the present invention is formed using the liquid crystal alignment agent of the present invention described above.

[0270] The manufacturing method of the liquid crystal alignment film of the present invention includes, for example, coating the above-mentioned liquid crystal alignment agent onto a substrate, firing it to obtain a film, and irradiating the film with polarized radiation.

[0271] As a preferred embodiment of the manufacturing method of the liquid crystal alignment film of the present invention, a manufacturing method of the liquid crystal alignment film including the following steps can be listed, for example: a step of coating the above-mentioned liquid crystal alignment agent onto a substrate (step (1)); a step of firing the coated liquid crystal alignment agent (step (2)); and a step of aligning the film obtained in step (2) as appropriate (step (3)).

[0272] <Process (1)>

[0273] As for the substrate used in this invention for coating the liquid crystal alignment agent, there are no particular limitations as long as it is a highly transparent substrate; glass substrates, silicon nitride substrates, acrylic substrates, polycarbonate substrates, and other plastic substrates can also be used. In this case, using a substrate with ITO (Indium Tin Oxide) electrodes for driving the liquid crystal is preferable from the perspective of process simplification. Furthermore, in reflective liquid crystal display elements, if it is a single-sided substrate, an opaque object such as a silicon wafer can be used, and the electrodes can be made of light-reflecting materials such as aluminum. Moreover, when manufacturing liquid crystal display elements using IPS or FFS driving methods, a substrate with electrodes formed of a transparent conductive film or metal film patterned in a comb-like shape and an opposing substrate without electrodes are used.

[0274] Methods for coating a liquid crystal alignment agent onto a substrate to form a film include screen printing, offset printing, flexographic printing, inkjet printing, and spraying. Among these, inkjet printing is preferred.

[0275] The IPS substrate, which is a comb electrode substrate used in the IPS mode, has: a substrate; a plurality of linear electrodes formed on the substrate and configured in a comb shape; and a liquid crystal alignment film formed on the substrate to cover the linear electrodes.

[0276] It should be noted that the FFS substrate used as the comb electrode substrate in the FFS mode has: a substrate; a surface electrode formed on the substrate; an insulating film formed on the surface electrode; a plurality of linear electrodes formed on the insulating film and arranged in a comb shape; and a liquid crystal alignment film formed on the insulating film to cover the linear electrodes.

[0277] Figure 1 This is a schematic cross-sectional view showing an example of an IPS mode lateral electric field liquid crystal display element having a liquid crystal alignment film obtained by the liquid crystal alignment agent of the present invention.

[0278] exist Figure 1 In the lateral electric field liquid crystal display element 1 illustrated in the example, liquid crystal 3 is held between a comb-shaped electrode substrate 2 having a liquid crystal alignment film 2c and an opposing substrate 4 having a liquid crystal alignment film 4a. The comb-shaped electrode substrate 2 includes: a substrate 2a; a plurality of linear electrodes 2b formed on the substrate 2a and arranged in a comb-like configuration; and a liquid crystal alignment film 2c formed on the substrate 2a to cover the linear electrodes 2b. The opposing substrate 4 includes: a substrate 4b; and a liquid crystal alignment film 4a formed on the substrate 4b. The liquid crystal alignment film 2c is the liquid crystal alignment film of the present invention. The liquid crystal alignment film 4c is also the liquid crystal alignment film of the present invention.

[0279] exist Figure 1 In the transverse electric field liquid crystal display element 1, when a voltage is applied to the linear electrode 2b, an electric field is generated between the linear electrodes 2b as shown by the electric field line L.

[0280] Figure 2 This is a schematic cross-sectional view showing an example of a lateral electric field liquid crystal display element having an FFS mode liquid crystal alignment film obtained by the liquid crystal alignment agent of the present invention.

[0281] exist Figure 2 In the lateral electric field liquid crystal display element 1 illustrated in the example, liquid crystal 3 is sandwiched between a comb-shaped electrode substrate 2 having a liquid crystal alignment film 2h and an opposing substrate 4 having a liquid crystal alignment film 4a. The comb-shaped electrode substrate 2 has: a substrate 2d; a surface electrode 2e formed on the substrate 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 configuration; and a liquid crystal alignment film 2h formed on the insulating film 2f to cover the linear electrodes 2g. The opposing substrate 4 has: a substrate 4b; and a liquid crystal alignment film 4a formed on the substrate 4b. The liquid crystal alignment film 2h is the liquid crystal alignment film of the present invention. The liquid crystal alignment film 4a is also the liquid crystal alignment film of the present invention.

[0282] exist Figure 2 In the transverse electric field liquid crystal display element 1, when a voltage is applied to the surface electrode 2e and the linear electrode 2g, an electric field is generated between the surface electrode 2e and the linear electrode 2g as shown by the electric field line L.

[0283] <Process (2)>

[0284] Step (2) is a step of firing the liquid crystal alignment agent coated on the substrate to form a film. After the liquid crystal alignment agent is coated on the substrate, the solvent can be evaporated using a heating unit such as a heating plate, a thermal cycling oven, or an IR (infrared) oven; or thermal imidization of the amyl acid or amyl ester in the polymer can be performed. The drying and firing steps after coating the liquid crystal alignment agent of the present invention can be performed at any temperature and time, and can be performed multiple times. As for the temperature at which the solvent of the liquid crystal alignment agent is evaporated, the temperature of the heating unit can be, for example, between 40 and 180°C, but from the viewpoint of shortening the process, it can be performed between 40 and 150°C. The firing time is not particularly limited, for example, between 1 and 10 minutes, preferably between 1 and 5 minutes. In the case where, in addition to the step of evaporating the solvent, a step of thermal imidization of the amyl acid in the polymer is also performed, the following step can be performed after the step of evaporating the solvent: the temperature of the heating unit is, for example, between 150 and 300°C, preferably within the temperature range of 150 and 250°C. The firing time in the thermal imidization process is not particularly limited, but is, for example, 5 to 40 minutes, preferably 5 to 30 minutes.

[0285] If the film after firing is too thin, the reliability of the liquid crystal display element may be reduced. Therefore, 5 to 300 nm is preferred, and 10 to 200 nm is more preferred.

[0286] <Process (3)>

[0287] Step (3) is a step of aligning the film obtained in step (2). Examples of alignment methods for liquid crystal alignment films include rubbing or photo-alignment, with photo-alignment being preferred. As a photo-alignment method, the following method can be used: irradiating the surface of the film with radiation polarized in a specific direction, followed by heating treatment as appropriate, to impart liquid crystal alignment properties (also known as liquid crystal alignment capability). As the radiation, ultraviolet light or visible light with a wavelength of 100–800 nm can be used. Preferably, ultraviolet light with a wavelength of 100–400 nm is used, and more preferably, ultraviolet light with a wavelength of 200–400 nm is used.

[0288] The preferred radiation dose is 1–10,000 mJ / cm². 2 More preferably, it is 100–5000 mJ / cm². 2 .

[0289] As a light source for illumination, for example, 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 (such as KrF excimer lasers), fluorescent lamps, LED lamps, halogen lamps (such as sodium lamps), microwave-discharged electrodeless lamps, etc.

[0290] Furthermore, when using polarized light as illumination, a higher extinction ratio of polarized light imparts greater anisotropy. For example, in the case of ultraviolet light, the extinction ratio of polarized ultraviolet light is more preferably 10:1 or higher, and even more preferably 20:1 or higher.

[0291] Furthermore, to improve liquid crystal alignment when irradiated with radiation, the substrate having the film can be heated at 50–250°C while being irradiated. The liquid crystal alignment film produced in this way allows the liquid crystal molecules to be stably aligned in a specific direction.

[0292] Furthermore, the liquid crystal alignment film irradiated with polarized radiation by the above method can also be contacted with a solvent, or the liquid crystal alignment film irradiated with radiation can be heated.

[0293] The solvent used in the above-described contact treatment is not particularly limited as long as it is capable of dissolving the decomposition products generated from the film-like material by radiation. Specific examples include: water, methanol, ethanol, 2-propanol, acetone, methyl ethyl ketone, 1-methoxy-2-propanol, 1-methoxy-2-propanol acetate, butyl cellosolve, ethyl lactate, methyl lactate, diacetone alcohol, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propyl acetate, butyl acetate, cyclohexyl acetate, etc. Among these, water, 2-propanol, 1-methoxy-2-propanol, or ethyl lactate are preferred from the perspective of versatility and solvent safety. Water, 1-methoxy-2-propanol, or ethyl lactate are more preferred. One solvent may be used, or a combination of two or more may be used.

[0294] Examples of the contact treatments described above include immersion treatment and spray treatment (also known as coating treatment). From the perspective of efficiently dissolving the decomposition products generated from the film by radiation irradiation, the treatment time in these treatments is preferably 10 seconds to 1 hour. Immersion treatment for 1 minute to 30 minutes is more preferred. Furthermore, the solvent used in the above contact treatments can be at room temperature or heated, preferably 10 to 80°C, more preferably 20 to 50°C. In addition, from the perspective of the solubility of the decomposition products, ultrasonic treatment or the like can be performed as needed.

[0295] Following the above contact treatment, rinsing (also called washing) and firing are preferably performed using low-boiling-point solvents such as water, methanol, ethanol, 2-propanol, acetone, and methyl ethyl ketone. At this time, either rinsing or firing, or both, can be performed. The firing temperature is preferably 150–300°C, more preferably 180–250°C, and even more preferably 200–230°C. Furthermore, the firing time is preferably 10 seconds to 30 minutes, more preferably 1 minute to 10 minutes.

[0296] The heat treatment of the above-mentioned radiation-irradiated coating is preferably performed at 50 to 300°C for 1 to 30 minutes, and more preferably at 120 to 250°C for 1 to 30 minutes.

[0297] (Liquid crystal display element)

[0298] The liquid crystal display element of the present invention has the liquid crystal alignment film of the present invention.

[0299] From the viewpoint of obtaining high liquid crystal alignment, the liquid crystal alignment film of the present invention is preferred as a liquid crystal alignment film for liquid crystal display elements of lateral electric field type such as IPS type and FFS type, and in particular, it is useful as a liquid crystal alignment film for liquid crystal display elements of FFS type.

[0300] Liquid crystal display elements can be manufactured by: after obtaining a substrate with a liquid crystal alignment film obtained by the liquid crystal alignment agent of the present invention, fabricating a liquid crystal cell by a known method, and dispensing liquid crystal into the liquid crystal cell. Specifically, the following two methods can be listed.

[0301] In the first method, two substrates are first arranged opposite each other with their respective liquid crystal alignment films facing each other, separated by a gap (cell gap). Next, the peripheries of the two substrates are bonded together using a sealant, and a liquid crystal composition is injected into the cell gap defined by the substrate surfaces and the sealant. After contact with the film surface, the injection hole is sealed.

[0302] The second method is known as 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. A liquid crystal composition is then dropped onto several predetermined locations on the surface of the alignment film. The other substrate is then bonded together with the alignment films facing each other, and the liquid crystal composition is spread across the entire surface of the substrate, contacting the film surface. Next, the entire surface of the substrate is irradiated with UV light to cure the sealant.

[0303] Regardless of whether the first or second method is used, it is ideal to further heat the liquid crystal composition to a temperature at which it becomes an isotropic phase, and then slowly cool it to room temperature, thereby removing the flow orientation during liquid crystal filling.

[0304] It should be noted that when the coating has undergone a friction treatment, the two substrates are arranged opposite each other at a predetermined angle, such as orthogonal or antiparallel, with the friction directions of each coating being opposite each other. Similarly, when a photo-alignment treatment has been performed, the substrates are arranged opposite each other with their alignment directions at a predetermined angle, such as orthogonal or antiparallel.

[0305] As a sealant, epoxy resin containing a curing agent and alumina spheres as spacers can be used, for example. Nematic liquid crystals and smectic liquid crystals can be cited as examples, with nematic liquid crystals being preferred.

[0306] There are no particular limitations on the liquid crystal composition. Any of the following can be used: a composition containing at least one liquid crystal compound (liquid crystal molecule) with positive dielectric anisotropy (also called positive liquid crystal composition, positive liquid crystal) or a liquid crystal composition with negative dielectric anisotropy (also called negative liquid crystal composition, negative liquid crystal), preferably a negative liquid crystal material.

[0307] The aforementioned liquid crystal composition may contain liquid crystal compounds having fluorine atoms, hydroxyl groups, amino groups, fluorine-containing groups (e.g., trifluoromethyl), cyano groups, alkyl groups, alkoxy groups, alkenyl groups, isothiocyanate groups, heterocyclic groups, cycloalkanes, cycloolefins, steroidal skeletons, benzene rings, or naphthalene rings. It may also contain compounds having two or more rigid sites (mesocrystalline skeletons) within the molecule that exhibit liquid crystal properties (e.g., bimesocrystalline compounds formed by two rigid biphenyl structures or terphenyl structures linked by alkyl groups). The liquid crystal composition may be a nematic liquid crystal composition, a smectic liquid crystal composition, or a cholesteric liquid crystal composition.

[0308] Furthermore, from the viewpoint of improving liquid crystal orientation, the above-mentioned liquid crystal composition may be further supplemented with additives. Such additives include: photopolymerizable monomers such as compounds having polymerizable groups, optically active compounds (e.g., S-811 manufactured by MERCK), antioxidants, ultraviolet absorbers, pigments, defoamers, polymerization initiators, or polymerization inhibitors.

[0309] Examples of positive liquid crystal displays include: ZLI-2293, ZLI-4792, MLC-2003, MLC-2041, MLC-3019, and MLC-7081 manufactured by MERCK.

[0310] 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.

[0311] In addition, in PSA mode, MLC-3023 manufactured by MERCK is an example of a liquid crystal containing a compound with polymerizable groups.

[0312] Next, the polarizing plates are set. Specifically, a pair of polarizing plates are attached to the surfaces of the two substrates opposite to the liquid crystal layer. Examples of polarizing plates include: a polarizing plate made by sandwiching a polarizing film called an "H film" between a cellulose acetate protective film; or a polarizing plate made of the H film itself, wherein the H film is formed by absorbing iodine while extending and oriented polyvinyl alcohol.

[0313] Example

[0314] The following examples illustrate the invention in further detail, but the invention is not limited to these examples. The abbreviations of the compounds used and the methods for determining their properties are described below.

[0315] (Organic solvent)

[0316] NMP: N-methyl-2-pyrrolidone.

[0317] NEP: N-ethyl-2-pyrrolidone.

[0318] GBL: γ-Butyrolactone.

[0319] MDPA: 3-methoxy-N,N-dimethylpropionamide.

[0320] BCS: Butyl cellosolve (ethylene glycol monobutyl ether).

[0321] DAA: Diacetone alcohol.

[0322] (Tetracarboxylic acid dianhydride)

[0323]

[0324] (Diamine)

[0325]

[0326] (Amino-terminal modifier)

[0327] Ac2O: Acetic anhydride.

[0328] MA: Maleic anhydride.

[0329] PA: Propionic anhydride.

[0330] SA: Succinic anhydride.

[0331] TESPSA: 3-Triethoxysilylpropylsuccinic anhydride.

[0332] Compound (e): A compound with the following structural formula.

[0333]

[0334] (additive)

[0335] AD-1: Acetic acid.

[0336] AD-2:3-Epoxypropoxypropyltriethoxysilane.

[0337] AD-3 to AD-6: Compounds with the following structural formulas.

[0338]

[0339] <Viscosity Measurement>

[0340] The measurement was performed using a TVE-22H type E viscometer (manufactured by Toki Sangyo Co., Ltd.), with a sample volume of 1.1 mL, using a conical rotor TE-1 (1°34', R24), at a temperature of 25°C.

[0341] <Evaluation of the Presence of Terminal Amino Groups>

[0342] Add 2.0 g of polyamic acid solution to 10 g of isopropanol, and filter out the resulting precipitate. Wash the precipitate with isopropanol, dry under reduced pressure at 60°C to obtain polyamic acid powder, and then... 1 Structural analysis was performed using 1H-NMR. The presence rate of the terminal amino groups was calculated based on the peak intensity of the terminal amino groups in the unmodified polyamic acid powder, according to the ratio of the peak intensity to that of the terminal amino groups in each polyamic acid powder (analytical conditions described below).

[0343] Device: BRUKER ADVANCE III-500MHz.

[0344] Determination solvent: deuterated dimethyl sulfoxide (DMSO-d6) or deuterated chloroform (CDCl3).

[0345] Reference material: Tetramethylsilane (TMS) (δ 0.0 ppm in 1H).

[0346] Synthesis of amino-terminal modifiers

[0347] Compound (e) is a novel compound not disclosed in the literature, and the synthesis method is described in detail below.

[0348] Compound (e) via 1 H-NMR analysis was used for identification (analytical conditions are described below).

[0349] Device: BRUKER ADVANCE III-500MHz.

[0350] Determination solvent: deuterated dimethyl sulfoxide (DMSO-d6) or deuterated chloroform (CDCl3).

[0351] Reference material: Tetramethylsilane (TMS) (δ 0.0 ppm in 1H).

[0352] The abbreviations used in this invention have the following meanings.

[0353] BOP reagent: Benzotriazole-N-hydroxytris(dimethylamino)phosphonium hexafluorophosphate.

[0354] <Synthesis of compound (e)>

[0355]

[0356] N,N'-di-tert-butoxycarbonylhistidine (17.7 g, 49.8 mmol), triethylamine (Et3N, 6.28 g, 62.1 mmol), and dichloromethane (CH2Cl2, 247 g) were added to a flask, and the resulting solution was cooled to 2 °C. BOP reagent (22.1 g, 50.0 mmol) was then added to the flask, and the mixture was stirred at 10 °C for 1 hour to allow the reaction to proceed. After the reaction, the precipitated crystals were filtered off, and the solid was washed twice with 2-propanol (70.0 g) and twice with acetonitrile (70.0 g). The resulting wet product was dried under vacuum at 40 °C to obtain compound (e) (yield: 8.31 g, 17.6 mmol, appearance: white solid, yield: 35%). Based on the following... 1 The H-NMR results confirmed that the solid was compound (e).

[0357] In CDCl3 1 H-NMR (500MHz): δ (ppm) = 8.09 (d, 1H, J = 1.0Hz), 8.03 (d, 1H, J = 8.4Hz), 7.61 (d, 1H, J = 8.3Hz), 7.52 (t, 1H, J = 7.2Hz), 7.41 (t, 1H, J=8.0Hz), 7.38 (s, 1H), 6.18 (d, 1H, J=7.0Hz), 4.99 (q, 1H, J=6.7Hz), 3.39-3.25 (m, 2H), 1.63 (s, 9H), 1.48 (s, 9H).

[0358] [Polymer Synthesis]

[0359] <Synthesis example 1>

[0360] 0.54 g (5.0 mmol) of DA-1, 1.83 g (7.5 mmol) of DA-2, 2.40 g (7.5 mmol) of DA-3, and 1.99 g (5.0 mmol) of DA-4 were measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 77.8 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the diamine solution. While stirring the solution under water cooling, 5.32 g (24.0 mmol) of CA-1 was added, followed by 10.8 g of NMP. The mixture was stirred at 40 °C for 20 hours under a nitrogen atmosphere to obtain polymer solution A-1.

[0361] <Synthesis example 2>

[0362] 5.26 g (26.4 mmol) of DA-5 and 1.00 g (6.6 mmol) of DA-6 were measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 45.9 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the diamine solution. While stirring the solution under water cooling, 9.03 g (30.7 mmol) of CA-2 was added, followed by 66.2 g of NMP. The mixture was stirred at 70 °C for 10 hours under a nitrogen atmosphere to obtain polymer solution B-1.

[0363] <Synthesis Example 3>

[0364] Add 0.05 g (0.5 mmol) of Ac2O to the above polymer solution A-1 (30 g) and stir at room temperature for 24 hours to obtain polymer solution C-1 containing non-amino-terminated structures.

[0365] <Synthesis example 4>

[0366] Add 0.06 g (0.6 mmol) of Ac2O to the above polymer solution B-1 (30 g) and stir at room temperature for 24 hours to obtain polymer solution D-1 containing non-amino-terminated structures.

[0367] <Synthesis Examples 5 to 16>

[0368] Using the polymer solutions shown in Table 1 below and the amino-terminal modifiers, the same operations as in Synthetic Examples 3 and 4 above were performed to obtain polymer solutions C-2 to 11 and D-2 to 3.

[0369] <Synthesis Example 17>

[0370] Add 0.18 g (3.0 mmol) of AD-1 to 30 g of the above polymer solution A-1, and stir at room temperature for 24 hours to obtain polymer solution E-1 without non-amino-terminal structures.

[0371]

[0372] [Polymer Synthesis]

[0373] <Synthesis Example 18>

[0374] 5.41 g (50.0 mmol) of DA-1 was measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 39.7 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the DA-1. While stirring the diamine solution under water cooling, 10.54 g (47.0 mmol) of CA-1 was added, followed by 77.3 g of NMP. The mixture was stirred at 40 °C for 20 hours under a nitrogen atmosphere to obtain polymer solution A-2.

[0375] <Synthesis Example 19>

[0376] 12.21 g (50.0 mmol) of DA-2 was measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 89.6 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the DA-2. While stirring the diamine solution under water cooling, 10.54 g (47.0 mmol) of CA-1 was added, followed by 77.3 g of NMP. The mixture was stirred at 40 °C for 20 hours under a nitrogen atmosphere to obtain polymer solution A-3.

[0377] <Synthesis Example 20>

[0378] 19.93 g (50.0 mmol) of DA-4 was measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 146.1 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the DA-4. While stirring the diamine solution under water cooling, 10.54 g (47.0 mmol) of CA-1 was added, followed by 77.3 g of NMP. The mixture was stirred at 40 °C for 20 hours under a nitrogen atmosphere to obtain polymer solution A-4.

[0379] <Synthesis Example 21>

[0380] 10.61 g (50.0 mmol) of DA-7 was measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 77.8 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the DA-7. While stirring the diamine solution under water cooling, 10.54 g (47.0 mmol) of CA-1 was added, followed by 77.3 g of NMP. The mixture was stirred at 40 °C for 20 hours under a nitrogen atmosphere to obtain polymer solution A-5.

[0381] <Synthesis Example 22>

[0382] 10.61 g (50.0 mmol) of DA-8 was measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 77.8 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the DA-8. While stirring the diamine solution under water cooling, 10.54 g (47.0 mmol) of CA-1 was added, followed by 77.3 g of NMP. The mixture was stirred at 40 °C for 20 hours under a nitrogen atmosphere to obtain polymer solution A-6.

[0383] <Synthesis Example 23>

[0384] 20.22 g (50.0 mmol) of DA-9 was measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 148.3 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the DA-9. While stirring the diamine solution under water cooling, 10.54 g (47.0 mmol) of CA-1 was added, followed by 77.3 g of NMP. The mixture was stirred at 40 °C for 20 hours under a nitrogen atmosphere to obtain polymer solution A-7.

[0385] <Synthesis Example 24>

[0386] 1.06 g (5.0 mmol) of DA-7, 1.83 g (7.5 mmol) of DA-2, 2.40 g (7.5 mmol) of DA-3, and 1.99 g (5.0 mmol) of DA-4 were measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 53.5 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the diamine solution. While stirring the solution under water cooling, 5.32 g (24.0 mmol) of CA-1 was added, followed by 39.0 g of NMP. The mixture was stirred at 40 °C for 20 hours under a nitrogen atmosphere to obtain polymer solution A-8.

[0387] <Synthesis Example 25>

[0388] 0.54 g (5.0 mmol) of DA-1, 1.59 g (7.5 mmol) of DA-8, 2.40 g (7.5 mmol) of DA-3, and 1.99 g (5.0 mmol) of DA-4 were measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 47.9 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the diamine solution. While stirring the solution under water cooling, 5.32 g (24.0 mmol) of CA-1 was added, followed by 39.0 g of NMP. The mixture was stirred at 40 °C for 20 hours under a nitrogen atmosphere to obtain polymer solution A-9.

[0389] <Synthesis Example 26>

[0390] 0.54 g (5.0 mmol) of DA-1, 1.83 g (7.5 mmol) of DA-2, 2.40 g (7.5 mmol) of DA-3, and 2.02 g (5.0 mmol) of DA-9 were measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 49.9 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the diamine solution. While stirring the solution under water cooling, 5.32 g (24.0 mmol) of CA-1 was added, followed by 39.0 g of NMP. The mixture was stirred at 40 °C for 20 hours under a nitrogen atmosphere to obtain polymer solution A-10.

[0391] <Synthesis Example 27>

[0392] 1.08 g (10.0 mmol) of DA-1, 1.83 g (7.5 mmol) of DA-2, and 2.40 g (7.5 mmol) of DA-3 were measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 39.0 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the diamine solution. While stirring the solution under water cooling, 5.32 g (24.0 mmol) of CA-1 was added, followed by another 39.0 g of NMP. The mixture was stirred at 40 °C for 20 hours under a nitrogen atmosphere to obtain polymer solution A-11.

[0393] <Synthesis Example 28>

[0394] 0.54 g (5.0 mmol) of DA-1, 1.83 g (7.5 mmol) of DA-2, 2.40 g (7.5 mmol) of DA-3, and 1.19 g (5.0 mmol) of DA-10 were measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 43.7 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the diamine solution. While stirring the solution under water cooling, 5.32 g (24.0 mmol) of CA-1 was added, followed by 39.0 g of NMP. The mixture was stirred at 40 °C for 20 hours under a nitrogen atmosphere to obtain polymer solution A-12.

[0395] <Synthesis Example 29>

[0396] 0.54 g (5.0 mmol) of DA-1, 1.83 g (7.5 mmol) of DA-2, 2.40 g (7.5 mmol) of DA-3, and 1.71 g (5.0 mmol) of DA-11 were measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 47.5 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the diamine solution. While stirring the solution under water cooling, 5.32 g (24.0 mmol) of CA-1 was added, followed by 39.0 g of NMP. The mixture was stirred at 40 °C for 20 hours under a nitrogen atmosphere to obtain polymer solution A-13.

[0397] <Synthesis Example 30>

[0398] 0.54 g (5.0 mmol) of DA-1, 1.83 g (7.5 mmol) of DA-2, 2.40 g (7.5 mmol) of DA-3, and 1.98 g (5.0 mmol) of DA-12 were measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 49.6 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the diamine solution. While stirring the solution under water cooling, 5.32 g (24.0 mmol) of CA-1 was added, followed by 39.0 g of NMP. The mixture was stirred at 40 °C for 20 hours under a nitrogen atmosphere to obtain polymer solution A-14.

[0399] <Synthesis Example 31>

[0400] 0.54 g (5.0 mmol) of DA-1, 1.83 g (7.5 mmol) of DA-2, 2.40 g (7.5 mmol) of DA-3, and 2.78 g (5.0 mmol) of DA-13 were measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 55.4 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the diamine solution. While stirring the solution under water cooling, 5.32 g (24.0 mmol) of CA-1 was added, followed by 39.0 g of NMP. The mixture was stirred at 40 °C for 20 hours under a nitrogen atmosphere to obtain polymer solution A-15.

[0401] <Synthesis Example 32>

[0402] 0.54 g (5.0 mmol) of DA-1, 1.83 g (7.5 mmol) of DA-2, 2.40 g (7.5 mmol) of DA-3, and 1.94 g (5.0 mmol) of DA-14 were measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 49.2 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the diamine solution. While stirring the solution under water cooling, 5.32 g (24.0 mmol) of CA-1 was added, followed by 39.0 g of NMP. The mixture was stirred at 40 °C for 20 hours under a nitrogen atmosphere to obtain polymer solution A-16.

[0403] <Synthesis Example 33>

[0404] 4.48 g (15.0 mmol) of DA-15 and 2.44 g (10.0 mmol) of DA-2 were measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 50.7 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the diamine solution. While stirring the solution under water cooling, 6.99 g (24.0 mmol) of CA-2 was added, followed by 51.2 g of NMP. The mixture was stirred at 70 °C for 10 hours under a nitrogen atmosphere to obtain polymer solution B-2.

[0405] <Synthesis Example 34>

[0406] 3.99 g (20.0 mmol) of DA-5 and 1.22 g (5.0 mmol) of DA-2 were measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 49.3 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the diamine solution. While stirring the solution under water cooling, 4.41 g (22.5 mmol) of CA-3 was added, followed by 21.2 g of NMP. The mixture was stirred at 40 °C for 10 hours under a nitrogen atmosphere to obtain polymer solution B-3.

[0407] <Synthesis Example 35>

[0408] 2.16 g (20.0 mmol) of DA-1 and 0.54 g (5.0 mmol) of DA-16 were measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 40.9 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the diamine solution. While stirring the solution under water cooling, 1.56 g (6.3 mmol) of CA-4 was added, followed by 5.0 g of NMP. The mixture was stirred at 50 °C for 3 hours under a nitrogen atmosphere. Then, while stirring the solution under water cooling, 3.53 g (18.0 mmol) of CA-3 was added, followed by 11.2 g of NMP. The mixture was stirred at 25 °C for 12 hours under a nitrogen atmosphere to obtain polymer solution B-4.

[0409] <Synthesis Example 36>

[0410] 2.99 g (15.0 mmol) of DA-5, 2.11 g (5.0 mmol) of DA-17, and 1.49 g (5.0 mmol) of DA-15 were measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 48.3 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the diamine solution. While stirring the solution under water cooling, 6.99 g (24.0 mmol) of CA-2 was added, followed by 51.2 g of NMP. The mixture was stirred at 70 °C for 10 hours under a nitrogen atmosphere to obtain polymer solution B-5.

[0411] <Synthesis Example 37>

[0412] 1.87 g (7.5 mmol) of DA-18, 2.49 g (12.5 mmol) of DA-5, and 0.99 g (5.0 mmol) of DA-19 were measured into a 100 mL flask equipped with a stirrer and a nitrogen inlet tube. 39.2 g of NMP was added, and the mixture was stirred while adding nitrogen to dissolve the diamine solution. While stirring the solution under water cooling, 1.72 g (8.8 mmol) of CA-3 was added, followed by 42.0 g of NMP. The mixture was stirred at 25 °C for 1 hour under a nitrogen atmosphere. Then, while stirring the solution under water cooling, 4.41 g (15.0 mmol) of CA-2 was added, followed by 2.9 g of NMP. The mixture was stirred at 25 °C for 5 hours under a nitrogen atmosphere to obtain polymer solution B-6.

[0413] <Synthesis Examples 38 to 53>

[0414] Using the polymer solutions shown in Table 2 below and the amino-terminal modifiers, the same operations as in Synthetic Examples 3 and 4 above were performed to obtain polymer solutions C-12 to C-27.

[0415]

[0416] Hereinafter, the tetracarboxylic acid dianhydride and diamine components used in the synthesis of the above polymer solutions (A-1) to (A-16) and (B-1) to (B-6) are described in Table 3 below.

[0417]

[0418]

[0419] [Preparation of liquid crystal alignment agent]

[0420] <Example 1>

[0421] Using the polymer solution B-1 and polymer solution C-1 described above, polymer solution C-1 (2.3 g) and polymer solution B-1 (2.3 g) were mixed in a mass ratio of 50:50. While stirring, NMP (9.6 g), BCS (5.0 g), an NMP solution containing 1% by weight of AD-2 (0.5 g), and an NMP solution containing 10% by weight of AD-3 (0.3 g) were added to the mixture, and the mixture was further stirred at room temperature for 2 hours to obtain the liquid crystal alignment agent (AL-1) of the present invention. Furthermore, a liquid crystal alignment agent (AL-1-48h) that was left at room temperature for 48 hours was also obtained to evaluate its effect on inhibiting the degradation of liquid crystal alignment.

[0422] <Examples 2-14 and Comparative Examples 1-3>

[0423] Using the compositions shown in Table 4 below, the same operations as in Example 1 were performed to obtain the liquid crystal alignment agents (AL-2) to (AL-14), (AL-2-48h) to (AL-14-48h) of Examples 2 to 14 of the present invention, and the liquid crystal alignment agents (AL-R1) to (AL-R3), (AL-R1-48h) to (AL-R3-48h) of Comparative Examples 1 to 3.

[0424]

[0425] <Examples 15-41 and Comparative Examples 4-30>

[0426] Using the compositions shown in Table 5 below, the same operations as in Example 1 were performed to obtain the liquid crystal alignment agents (AL-15) to (AL-41), (AL-15-48h) to (AL-41-48h) of Examples 15 to 41 of the present invention, and the liquid crystal alignment agents (AL-R4) to (AL-R30), (AL-R4-48h) to (AL-R30-48h) of Comparative Examples 4 to 30.

[0427]

[0428]

[0429]

[0430]

[0431] [Making of LCD Cells]

[0432] Using the liquid crystal alignment agent obtained above, an FFS-driven liquid crystal cell as shown below was fabricated.

[0433] (The structure of an FFS-driven liquid crystal cell)

[0434] The liquid crystal cell used in FFS mode consists of a first glass substrate and a second glass substrate. The first glass substrate has an FOP (Finger on Plate) electrode layer formed on its surface, which is composed of a common electrode in a planar shape, an insulating layer, and pixel electrodes in a comb shape. The second glass substrate has columnar spacers with a height of 4 μm on its surface and an ITO film for antistatic purposes formed on its back side. The pixel electrodes have a comb shape formed by multiple 3 μm wide electrode elements with a central portion bent at an inner angle of 160° and spaced 6 μm apart in parallel. A pixel has a first region and a second region bounded by the bent lines connecting the multiple electrode elements. It should be noted that the liquid crystal alignment film formed on the first glass substrate is aligned such that the direction in which the inner angle of the pixel bend is equally divided is orthogonal to the alignment direction of the liquid crystal. The liquid crystal alignment film formed on the second glass substrate is aligned such that the alignment direction of the liquid crystal on the first substrate is consistent with the alignment direction of the liquid crystal on the second substrate when the liquid crystal cell is manufactured.

[0435] (Fabrication of FFS-driven liquid crystal cells (photoalignment processing))

[0436] Next, the liquid crystal alignment agents obtained in Examples 1-14 and Comparative Examples 1-3 were filtered using a filter with a pore size of 1.0 μm, and then spin-coated onto the surfaces of the electrode substrate and the glass substrate with an ITO film on the back side and columnar spacers with a height of 4 μm. After drying on a heating plate at 80°C for 2 minutes, the coating was fired in a hot air circulating oven at 230°C for 30 minutes to form a coating film with a thickness of 100 nm.

[0437] Irradiate the coated surface with 0.3 J / cm 2 Ultraviolet light with a wavelength of 254 nm was linearly polarized by a polarizer with an extinction ratio of 26:1. The substrate was then fired in a hot air circulating oven at 230°C for 30 minutes to obtain a substrate with a liquid crystal alignment film.

[0438] (Friction orientation treatment)

[0439] Next, using the liquid crystal alignment agent obtained in Example 41 and Comparative Example 30 above, a coating film with a thickness of 100 nm was formed in the same order as described above. Then, the photoalignment process was changed to the rubbing alignment process described below, and alignment treatment was performed.

[0440] Specifically, the substrate with the coating was rubbed with rayon cloth (roller diameter: 140 mm, roller speed: 1000 rpm, moving speed: 20 mm / sec, pressing length: 0.4 mm). Then, it was cleaned by ultrasonic irradiation in pure water for 1 minute, and after the water droplets were removed by blowing air, it was dried at 80°C for 10 minutes to obtain a substrate with a liquid crystal alignment film.

[0441] Using the two substrates obtained above as a group, a sealant was applied to one substrate, and the other substrate was bonded together with the liquid crystal alignment film surfaces facing each other and the alignment direction at 0°. The sealant was then cured to create an empty cell. Liquid crystal MLC-3019 (manufactured by MERCK) was injected into this empty cell using a reduced-pressure injection method, and the injection port was sealed to create an FFS-driven liquid crystal cell. The obtained FFS-driven liquid crystal cell was heated at 120°C for 1 hour and then placed at 23°C overnight before being used for the following evaluation.

[0442] [Characteristics Evaluation of LCD Cells]

[0443] The characteristics of the liquid crystal cell manufactured above are evaluated as follows.

[0444] (Afterimage characteristics caused by long-term communication)

[0445] The FFS-driven liquid crystal cell fabricated above was subjected to an AC voltage of ±7V at a frequency of 60Hz for 120 hours under a backlight illumination of 15000 nits. Then, the pixel electrode and the counter electrode of the liquid crystal cell were short-circuited, and this state was maintained at room temperature for one day. For the liquid crystal cell subjected to the above treatment, the deviation in orientation direction between the liquid crystal in the first region and the liquid crystal in the second region of the pixel under the un-voltage-applied state was calculated in terms of angles.

[0446] Specifically, the liquid crystal cell is positioned between two polarizing plates orthogonally arranged with their polarization axes aligned. The backlight is turned on, and the cell's orientation angle is adjusted to minimize the transmitted light intensity in the first region of the pixel. Then, the rotation angle required to minimize the transmitted light intensity in the second region of the pixel is determined. It can be said that the smaller this rotation angle, the better the image retention characteristics caused by long-term AC drive.

[0447] [Evaluation Results]

[0448] To confirm the effectiveness of suppressing the degradation of liquid crystal alignment as the objective of this invention, the following evaluation was conducted. Specifically, the rotation angle Δa of the liquid crystal cell using the liquid crystal alignment agents (AL-1) to (AL-14), (AL-R1) to (AL-R3) obtained in Examples 1 to 14 and Comparative Examples 1 to 3 was first calculated, as was the rotation angle Δb of the liquid crystal cell using the liquid crystal alignment agents (AL-1-48h) to (AL-14-48h), (AL-R1-48h) to (AL-R3-48h) that were placed at room temperature for 48 hours.

[0449] Next, the change in rotation angle Δ(|Δb-Δa|) caused by the room temperature storage of each liquid crystal alignment agent is set as an index representing the degree of deterioration of liquid crystal alignment. A value less than 0.2° is defined as "0", and a value greater than 0.2° is defined as "×".

[0450] The evaluation results are shown in Table 6. In the table, the values ​​in parentheses for the tetracarboxylic acid components represent the amount (mole parts) of each tetracarboxylic dianhydride used relative to the total amount of tetracarboxylic acid components used for polymerization (100 moles).

[0451]

[0452] It has been confirmed that the liquid crystal cell using the liquid crystal alignment agent of the present invention exhibits good liquid crystal alignment, meaning that it can suppress the deterioration of liquid crystal alignment caused by room temperature storage. A detailed comparison is described below.

[0453] Comparing Examples 1-2 with Comparative Example 1, it is evident that the lower the presence rate of the terminal amino groups, the better the liquid crystal alignment. Furthermore, comparing Examples 2 and 10 with Comparative Examples 1 and 2, it is evident that the contribution of the presence rate of the terminal amino groups to liquid crystal alignment varies greatly depending on the type of polyamic acid. Moreover, according to Comparative Example 3, it was confirmed that when acetic acid is added as an additive (i.e., the terminal amino groups are not modified to have the non-amino form of formula (E), the deterioration of liquid crystal alignment cannot be suppressed.

[0454] Furthermore, it was confirmed that the change in rotation angle of the liquid crystal cell using the liquid crystal alignment agent of the present invention is less than 0.2°, which can suppress the deterioration of liquid crystal alignment caused by room temperature storage.

[0455] Furthermore, for the liquid crystal alignment agents (AL-15) to (AL-41), (AL-15-48h) to (AL-41-48h), (AL-R4) to (AL-R30), and (AL-R4-48h) to (AL-R30-48h) obtained in Examples 15 to 41 and Comparative Examples 4 to 30, the rotation angles Δa and Δb were calculated in the same order. Next, the change in rotation angle Δ(|Δb-Δa|) caused by room temperature storage of each liquid crystal alignment agent was set as an index representing the degree of deterioration of liquid crystal alignment. A value less than 0.2° was defined as "0", and a value greater than 0.2° was defined as "×". The evaluation results are shown in Table 7.

[0456]

[0457]

[0458]

[0459]

[0460] Based on the comparison between Examples 15-41 and Comparative Examples 4-30, it was confirmed that even if the type of diamine, solvent, additive, and orientation method are changed, the deterioration of liquid crystal orientation can still be suppressed, and the scope of application of the present invention is very wide.

[0461] It should be noted that the entire contents of the specification, claims, drawings and abstract of Japanese Patent Application No. 2023-067329, filed on April 17, 2023, are incorporated herein as a disclosure of the specification of this invention.

Claims

1. A liquid crystal alignment agent, characterized in that, It contains polymer A and polymer B as described below. Polymer A: Polyamic acid A having structural units derived from tetracarboxylic acid derivatives and structural units derived from diamines, wherein the polyamic acid, As a structural unit derived from a tetracarboxylic acid derivative, it comprises the following formula (1T) a The structural unit a-1Ta shown in the figure is... As a structural unit derived from diamine, it includes the following formula (1D a The structural unit a-1Da shown in the figure, At least a portion of the polyamic acid A has a terminal portion containing a non-amino group, which is a functional group represented by the following structural formula (E). The presence rate of terminal amino groups in polyamic acid A is less than 60% based on all terminals of polyamic acid A. Polymer B: Polyamic acid B having structural units derived from tetracarboxylic acid derivatives and structural units derived from diamines, wherein the polyamic acid, As a structural unit derived from a tetracarboxylic acid derivative, it comprises the following formula (1T) b The structural unit b-1Tb shown is shown in the diagram. As a structural unit derived from diamine, it includes the following formula (1D b The structural unit b-1Db shown is shown in the diagram. In the formula X a This represents the tetravalent organic group shown in the following formula (x-1); formula (1D) a ), Y a The represents a divalent organic group derived from a diamine; Z ... In formula (x-1), R1 to R4 each independently represent a hydrogen atom, a halogen atom, an alkyl group with 1 to 6 carbon atoms, an alkenyl group with 2 to 6 carbon atoms, an alkynyl group with 2 to 6 carbon atoms, a monovalent organic group containing a fluorine atom with 1 to 6 carbon atoms, an alkoxy group with 1 to 6 carbon atoms, an alkoxyalkyl group with 2 to 6 carbon atoms, an alkoxycarbonyl group with 2 to 6 carbon atoms, or a phenyl group. At least one of R1 to R4 represents a group other than a hydrogen atom as defined above; * indicates a bond. In the formula X b T represents a tetravalent organic group derived from an aromatic tetracarboxylic acid dianhydride, a tetravalent organic group represented by the following formula (x-2), or a tetravalent organic group having an alicyclic structure with five or more members. 5a ; formula (1D) b ), Y b Z represents a divalent organic group derived from a diamine; Z and the formula (1D) a The Z in ) has the same meaning. In formula (E), Q is a monovalent organic group selected from any of the following groups e1 to e3; * indicates a bond. e1: A non-cyclic hydrocarbon group with 1 to 6 carbon atoms. e2: A monovalent organic group having 1 to 2 carboxyl groups and 2 to 30 carbon atoms, wherein the monovalent organic group does not contain anhydride groups. e3: A monovalent organic group having two or more Boc atoms, and excluding Boc atoms, having 1 to 30 carbon atoms, wherein the monovalent organic group has a protected amino group selected from the group consisting of *1-NH(Boc), *1-N(Boc)2 and "*1-N(Boc)-*1", wherein *1 represents a bond bonded to a carbon atom; it should be noted that when there are two or more protected amino groups, the protected amino groups may optionally be the same or different.

2. The liquid crystal alignment agent according to claim 1, wherein, The e1 is a residue derived from acyclic aliphatic dicarboxylic anhydrides.

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

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

5. The liquid crystal alignment agent according to claim 3, wherein, The compound e2-2 is selected from the following compounds: 4-(3-trimethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-triethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-trimethoxysilylpropyl)phthalic anhydride, 4-(3-triethoxysilylpropyl)phthalic anhydride, alkoxydimethylsilyl alkyl succinic anhydride having 1 to 6 carbon atoms and alkyl succinic anhydride having 2 to 8 carbon atoms; alkyl succinic anhydride having 1 to 6 carbon atoms. alkyl succinic anhydride with 2 to 8 carbon atoms; alkyl succinic anhydride with 1 to 6 carbon atoms and 2 to 8 carbon atoms; 4-(3-dimethylmethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-dimethylethoxysilylpropyl)cyclohexane-1,2-dicarboxylic anhydride, 4-(3-dimethylmethoxysilylpropyl)phthalic anhydride or 4-(3-dimethylethoxysilylpropyl)phthalic anhydride.

6. The liquid crystal alignment agent according to claim 1, wherein, The e3 is obtained using the active ester compound e as shown in R-O-C(=O)-E3, where E3 represents the e3 and R represents the active ester forming group.

7. The liquid crystal alignment agent according to claim 6, wherein, The E3 group is formed by removing the carboxyl group from the carboxylic acid W represented by "W-COOH". In "W-COOH", W and E3 have the same meaning. The carboxylic acid W is obtained by protecting the amino groups of a carboxyl-containing polyamine pA having two or more amino groups.

8. The liquid crystal alignment agent according to claim 1, wherein, The expression (x-1) is selected from the group consisting of the following expressions (x1-1) to (x1-5). In the formula, * represents a bond.

9. The liquid crystal alignment agent according to claim 1, wherein, The structural unit a-1Da and / or the structural unit b-1Db are structural units 1D-1 derived from the following diamine: the diamine is selected from diamine OH-N(Z)-Ar1-L1-A-L. 1’ -Ar 1’ -N(Z)-H”, diamine Ph"H-N(Z)-Ar-N(Z)-H” and diamine O'"H-N(Z)-Ar2-L2-A2-L 2’ -Ar 2’ In the group consisting of diamines represented by "-N(Z)-H", In the formula, Ar1 and Ar 1’ Each independently represents a benzene ring, biphenyl structure, or naphthalene ring; Ar1, Ar 1’ Any hydrogen atom on the ring may be optionally replaced by a monovalent group; A represents a divalent organic group with 1 to 10 carbon atoms having an alkylene structure. L1, L 1’ Each of these can independently represent a single bond, -O-, -S-, -C(=O)-, -O-C(=O)-, -NR-, -C(=O)-NR-, or -NR-C(=O)-, where -NR- represents a hydrogen atom or a monovalent organic group, -C(=O)-NR- represents a hydrogen atom or a monovalent organic group, and -NR-C(=O)- represents a hydrogen atom or a monovalent organic group. Ar represents a benzene ring, a biphenyl structure, a naphthalene ring, or a divalent organic group as shown in the following formula (Im); any hydrogen atom on the benzene ring, biphenyl structure, or naphthalene ring of Ar may optionally be replaced by a monovalent group. Z and the aforementioned formula (1D) a The Z in ) has the same meaning. Ar2 and Ar 2’ Each independently represents a benzene ring, biphenyl structure, naphthalene ring, or aromatic heterocycle; Ar2 and Ar 2’ Any hydrogen atom on the ring may be optionally replaced by a monovalent group; A2 represents a divalent organic group having an alkylene group. L2, L 2’ Each of these can independently represent a single bond, -O-, -S-, -C(=O)-, -O-C(=O)-, -NR-, -C(=O)-NR-, or -NR-C(=O)-, where -NR- represents a hydrogen atom or a monovalent organic group, -C(=O)-NR- represents a hydrogen atom or a monovalent organic group, and -NR-C(=O)- represents a hydrogen atom or a monovalent organic group. Among them, Ar2 and Ar 2’ And any one of A2 has a heterocyclic ring. In formula (Im), X represents a tetravalent organic group obtained by removing two anhydride groups from an acyclic or alicyclic tetracarboxylic dianhydride.

10. A liquid crystal alignment agent, characterized in that, By containing polymers A and B, a liquid crystal alignment film with a rotation angle change of less than 0.2°, as shown in Formula 1, can be obtained. Polymer A: Polyamic acid A having structural units derived from tetracarboxylic acid derivatives and structural units derived from diamines, wherein the polyamic acid, As a structural unit derived from a tetracarboxylic acid derivative, it comprises the following formula (1T) a The structural unit a-1Ta shown in the figure is... As a structural unit derived from diamine, it includes the following formula (1D a The structural unit a-1Da shown in the figure, At least a portion of the polyamic acid A has a terminal portion containing a non-amino group, which is a functional group represented by the following structural formula (E). Polymer B: Polyamic acid B having structural units derived from tetracarboxylic acid derivatives and structural units derived from diamines, wherein the polyamic acid, As a structural unit derived from a tetracarboxylic acid derivative, it comprises the following formula (1T) b The structural unit b-1Tb shown is shown in the diagram. As a structural unit derived from diamine, it includes the following formula (1D b The structural unit b-1Db shown is shown in the diagram. In the formula X a This represents the tetravalent organic group shown in the following formula (x-1); formula (1D) a ), Y a The represents a divalent organic group derived from a diamine; Z ... In formula (x-1), R1 to R4 each independently represent a hydrogen atom, a halogen atom, an alkyl group with 1 to 6 carbon atoms, an alkenyl group with 2 to 6 carbon atoms, an alkynyl group with 2 to 6 carbon atoms, a monovalent organic group containing a fluorine atom with 1 to 6 carbon atoms, an alkoxy group with 1 to 6 carbon atoms, an alkoxyalkyl group with 2 to 6 carbon atoms, an alkoxycarbonyl group with 2 to 6 carbon atoms, or a phenyl group. At least one of R1 to R4 represents a group other than a hydrogen atom as defined above; * indicates a bond. In the formula X b T represents a tetravalent organic group derived from an aromatic tetracarboxylic acid dianhydride, a tetravalent organic group represented by the following formula (x-2), or a tetravalent organic group having an alicyclic structure with five or more members. 5a ; formula (1D) b ), Y b Z represents a divalent organic group derived from a diamine; Z and the formula (1D) a The Z in ) has the same meaning. In formula (E), Q is a monovalent organic group selected from any of the following groups e1 to e3; * indicates a bond. e1: A non-cyclic hydrocarbon group with 1 to 6 carbon atoms. e2: A monovalent organic group having 1 to 2 carboxyl groups and 2 to 30 carbon atoms, wherein the monovalent organic group does not contain anhydride groups. e3: A monovalent organic group having two or more Boc atoms, excluding Boc atoms, and having 1 to 30 carbon atoms, wherein the monovalent organic group has a protected amino group selected from the group consisting of *1-NH(Boc), *1-N(Boc)2, and "*1-N(Boc)-*1", wherein *1 represents a bond bonded to a carbon atom; it should be noted that when there are two or more protected amino groups, the protected amino groups may optionally be the same or different. Formula 1: Δ=|Δb-Δa| Δ: The change in rotation angle after 48 hours of storage at room temperature. Δa: Rotation angle of the liquid crystal cell Δb: The rotation angle of the liquid crystal cell using the same liquid crystal alignment agent placed at room temperature for 48 hours. In Equation 1, the rotation angle is as follows: Two substrates with liquid crystal alignment films are used as a group. A sealant is applied to one substrate, and the other substrate is bonded together with the liquid crystal alignment film surfaces facing each other and the alignment direction being 0°. The sealant is then cured, liquid crystal is injected, and the injection port is sealed to obtain a liquid crystal cell. The obtained liquid crystal cell is lit with a backlight of 15000 nits and an AC voltage of ±7V at a frequency of 60Hz is applied for 120 hours. The pixel electrode and the counter electrode of the liquid crystal cell are then short-circuited. The cell is left at room temperature for one day. The deviation between the alignment direction of the liquid crystal in the first region of the pixel and the alignment direction of the liquid crystal in the second region of the pixel is calculated for the liquid crystal cell under the condition of no voltage application.

11. A method for manufacturing a liquid crystal alignment film, comprising: The liquid crystal alignment agent as described in any one of claims 1 to 10 is coated onto a substrate, fired, and the resulting film is irradiated with polarized radiation.

12. The method for manufacturing a liquid crystal alignment film according to claim 11, wherein, The firing temperature during the firing process is 150–250°C.

13. A liquid crystal alignment film formed from a liquid crystal alignment agent as described in any one of claims 1 to 10.

14. A liquid crystal display element comprising the liquid crystal alignment film as described in claim 13.

15. The liquid crystal display element according to claim 14, wherein, The liquid crystal display element is driven by either IPS or FFS.

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