JP5045241B2 - Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element - Google Patents

Description

  The present invention provides a heterocyclic compound having one or more heterocyclic structures selected from the group consisting of oxetane, thiirane, aziridine, and oxazoline, and at least one polymer selected from a polyamic acid and a derivative of this polyamic acid, The present invention relates to a liquid crystal aligning agent dissolved in a solvent, a liquid crystal aligning film formed from the liquid crystal aligning agent, and a liquid crystal display element including the same.

  Liquid crystal display elements are used in various liquid crystal display devices such as monitors for notebook computers and desktop computers, video camera viewfinders, and projection displays. Recently, they have also been used as televisions. . Furthermore, it is also used as an optoelectronic-related element such as an optical printer head, an optical Fourier transform element, or a light valve.

  The liquid crystal display element usually has 1) a pair of substrates arranged opposite to each other, 2) electrodes formed on one or both of the opposed surfaces of each of the pair of substrates, and 3) each of the pair of substrates. And 4) a liquid crystal layer formed between the pair of substrates.

  As a conventional liquid crystal display element, a display element using a nematic liquid crystal is a mainstream, and 1) a TN (twisted nematic) type liquid crystal display element twisted by 90 degrees, and 2) a STN (super twisted nematic) twisted usually by 180 degrees or more. 3) A so-called TFT (Thin Film Transistor) type liquid crystal display element using a thin film transistor has been put into practical use. These liquid crystal display elements have a drawback that a viewing angle at which an image can be properly viewed is narrow, and when viewed from an oblique direction, luminance and contrast decrease and luminance inversion occurs in a halftone.

  In recent years, the problem of viewing angle is as follows: 1) TN-TFT type liquid crystal display element using optical compensation film, 2) VA (vertical alignment) type liquid crystal display element using vertical alignment and optical compensation film, 3) vertical MVA (Multi Domain Vertical Alignment) type liquid crystal display element using alignment and protrusion structure technology together, or 4) IPS (In-Plane Switching) type liquid crystal display element of lateral electric field type, 5) ECB (Electrically Controlled Birefringence type) Liquid crystal display element, 6) Optically compensated bend (Optically self-compensated birefringence: OCB) type liquid crystal It has been improved by techniques such as display elements, and the improved techniques have been put into practical use or are being studied.

  The development of the technology of the liquid crystal display element is achieved not only by simply improving these driving methods and element structures, but also by improving the components used in the liquid crystal display element. Among the components used in the liquid crystal display element, the liquid crystal alignment film is one of the important elements related to the display quality of the liquid crystal display element. Roles are becoming important year after year.

The liquid crystal alignment film is prepared from a liquid crystal aligning agent. The liquid crystal aligning agent mainly used at present is a solution in which polyamic acid or soluble polyimide is dissolved in an organic solvent. After applying such a solution to a substrate, a polyimide-based alignment film is formed by film formation by means such as heating. Various liquid crystal aligning agents other than polyamic acid are also being studied, but they are almost practical in terms of heat resistance, chemical resistance (liquid crystal resistance), coating properties, liquid crystal alignment properties, electrical properties, optical properties, display properties, etc. It has not been converted.

  An important characteristic required for the liquid crystal alignment film in order to improve the display quality of the liquid crystal display element is a voltage holding ratio. When the voltage holding ratio is low, the voltage applied to the liquid crystal during the frame period is lowered, and as a result, the luminance is lowered, and normal gradation display may be hindered. Moreover, even if the initial voltage holding ratio is high, there is a problem when the voltage holding ratio (long-term reliability) after the high temperature acceleration test is lowered.

In recent years, several methods have been proposed as an attempt to solve the above problems.
1) A polyamic acid composition containing a combination of two or more polyamic acids having different physical properties for forming a liquid crystal alignment film is known (see, for example, Patent Documents 1 and 2).
2) A varnish composition containing a polymer component containing polyamic acid and polyamide and a solvent is known (see, for example, Patent Document 3).
3) A varnish composition containing two or more polyamic acids and polyamides having different physical properties and a solvent is known (for example, see Patent Document 4).
4) A varnish composition containing a polymer material containing a polyamic acid or the like synthesized using a diamine compound having a specific structure is known (see, for example, Patent Document 5).
5) A technique of adding a low-molecular epoxy resin to polyimide and polyamic acid varnish is known (see, for example, Patent Document 6).

  However, in these prior arts, there is still room for study on the problems of voltage holding ratio and long-term reliability.

  Further, a liquid crystal aligning agent containing a polyamic acid and a curing accelerator having an oxazoline structure is known (see, for example, Patent Document 7). However, this curing accelerator is said to evaporate, sublimate and decompose in imidization when producing a liquid crystal alignment film, and in the liquid crystal alignment film produced using such a liquid crystal alignment film, the curing accelerator is a liquid crystal. The effect on the electrical properties of the alignment film has not been studied.

JP 11-193345 A JP-A-11-193347 International Publication No. 00/61684 Pamphlet WO 01/000733 pamphlet JP 2002-162630 A JP 2005-189270 A JP-A-9-302225

  In view of the above situation, development of a liquid crystal aligning agent for a liquid crystal display element with improved voltage holding ratio and long-term reliability, a liquid crystal alignment film formed using the same, and a liquid crystal display element including the same Is desired.

The present inventors have intensively studied to solve the above problems.
As a result, one or two or more polyamic acids obtained by reacting oxetane, thiirane, aziridine, and a compound having one or more heterocyclic structures with oxazoline, tetracarboxylic dianhydride and diamine, or the same The present invention has been completed by finding that a good voltage holding ratio and long-term reliability can be imparted to a liquid crystal display device comprising a liquid crystal alignment film prepared using a liquid crystal aligning agent containing a derivative. .

  Furthermore, it has been found that by appropriately selecting the polyamic acid, a liquid crystal alignment film produced using the liquid crystal aligning agent can be appropriately applied to liquid crystal display elements of various display drive systems.

  The present invention has the following configuration.

[1] containing a heterocyclic compound having one or more heterocyclic structures selected from the group consisting of oxetane, thiirane, aziridine, and oxazoline, and one or more polymers selected from polyamic acid and derivatives thereof It is a liquid crystal aligning agent, Comprising: The said heterocyclic compound is 0.1-50 weight% with respect to the said polymer, The liquid crystal aligning agent characterized by the above-mentioned.

[2] The liquid crystal aligning agent according to [1], wherein the heterocyclic compound is a compound having two or more of the heterocyclic structures.

[3] The liquid crystal aligning agent according to [1] or [2], wherein the heterocyclic compound is a polymer having the heterocyclic structure in a side chain.

[4] The liquid crystal aligning agent according to [3], wherein the polymer is a copolymer.

[5] The polyamic acid is a reaction product obtained by reacting tetracarboxylic dianhydride as an acid component and diamine as an amine component, any one of [1] to [4] A liquid crystal aligning agent according to item.

[6] The acid component includes an A component and a B component, and an aromatic tetracarboxylic dianhydride is used as the A component of the acid. The aromatic tetracarboxylic dianhydride has the following structural formula (1), (2) The liquid crystal aligning agent according to [5], which is a compound selected from the group consisting of (5) to (7) and (14).

 [7] The liquid crystal aligning agent according to [6], wherein the aromatic tetracarboxylic dianhydride is a compound of the structural formula (1).

[8] The liquid crystal according to [6] or [7], wherein one or both of an aliphatic tetracarboxylic dianhydride and an alicyclic tetracarboxylic dianhydride is used as the B component of the acid. Alignment agent.

[9] The aliphatic tetracarboxylic dianhydride and the alicyclic tetracarboxylic dianhydride are represented by the following structural formulas (19), (23), (25), (35) to (37), (39). The liquid crystal aligning agent according to [8], which is a compound selected from the group consisting of (44) and (49).

[10] The liquid crystal according to [9], wherein the alicyclic tetracarboxylic dianhydride is a compound selected from the group consisting of the structural formulas (19), (23) and (49). Alignment agent.

[11] The amine component includes an A component and a B component, and a diamine represented by a general formula selected from the group consisting of the following general formulas (I) to (VII) is used as the A component of the amine. The liquid crystal aligning agent as described in any one of [5] to [10].

In the general formula (I), A ¹ is, - (CH _{2) m} - represents a. Here, m represents an integer of 1 to 12. In general formulas (III), (V), and (VII), A ¹ is independently a single bond, —O—, —S—, —SS—, —SO ₂ —, —CO—, — CONH -, - NHCO -, - C (CH 3) 2 -, - C (CF 3) 2 -, - (CH 2) m -, - O- (CH 2) m -O-, or -S- ( CH ₂₎ represents an _m -S-. Here, m represents an integer of 1 to 12. In general formula (VI), A ² is independently a single bond, —O—, —S—, —CO—, —C (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ —, or carbon number. 1-6 alkylene is represented. Hydrogen which is further coupled to the general formula (II) ~ (VII) cyclohexane ring or a benzene ring in the, -F _{independently, -CH 3, -OH, -COOH,} -SO 3 H, -PO 3 H ₂ , may be replaced with benzyl or 4-hydroxybenzyl.

[12] The diamine of component A is represented by the following structural formulas (IV-1), (IV-2), (IV-15), (IV-16), (V-1) to (V-12), (V -33) The liquid crystal aligning agent according to [11], which is a compound selected from the group consisting of (VII-1) and (VII-2).

[13] The diamine represented by the general formula selected from the group consisting of the following general formulas (VIII) and (IX) to (XII) is used as the B component of the amine [11] or [12 ] The liquid crystal aligning agent of a description.

In the general formula (VIII), R ¹ is a single bond, —O—, —CO—, —COO—, —OCO—, —CONH—, —CH ₂ O—, —CF ₂ O— or (CH ₂ ) _e. -And e is an integer of 1 to 6; R ² is a group having a steroid skeleton, a group represented by the general formula (XIII), alkyl having 1 to 30 carbons, or phenyl; When the carbon number is 2-6, any —CH ₂ — may be independently replaced with —O— (but not consecutively), —CH═CH— or —C≡C—, and The phenyl hydrogen may be independently replaced by fluorine, methyl, methoxy, fluoromethoxy, difluoromethoxy or trifluoromethoxy.

In the general formula (IX), R ³ is independently hydrogen or methyl; R ⁴ is hydrogen or alkyl having 1 to 30 carbon atoms; R ⁵ is independently a single bond, —CO— or —CH _2. -.

In the general formula (X), R ³ is independently hydrogen or methyl; R ⁴ is hydrogen or alkyl having 1 to 30 carbon atoms; R ⁵ is independently a single bond, —CO— or —CH _2. And R ⁶ and R ⁷ are independently hydrogen, alkyl having 1 to 30 carbons, or phenyl.

In the general formula (XI), R ⁸ is hydrogen or alkyl having 1 to 30 carbon atoms, and any —CH ₂ — in the alkyl is —O— (but not consecutively), —CH═CH— or -C≡C- may be substituted; R ⁹ is independently -O- or alkylene having 1 to 6 carbon atoms; ring A is 1,4-phenylene or 1,4-cyclohexylene; a is 0 or 1; b is 0, 1 or 2; and c is independently 0 or 1.

In General Formula (XII), R ¹⁰ is alkyl having 3 to 30 carbons or fluorinated alkyl having 3 to 30 carbons; R ¹¹ is hydrogen, alkyl having 1 to 30 carbons, or 1 to 30 carbons. R ¹² is independently —O— or alkylene having 1 to 6 carbons; and d is independently 0 or 1.

In the general formula (XIII), R ¹³ , R ¹⁴ and R ¹⁵ are each independently a single bond, —O—, —COO—, —OCO—, —CONH—, alkylene having 1 to 4 carbons, 3 oxyalkylene, or alkyleneoxy having 1 to 3 carbon atoms (provided that oxygen is not continuously bonded); R ¹⁶ and R ¹⁷ are independently hydrogen, fluorine or methyl; R ¹⁸ is hydrogen, fluorine Chlorine, cyano, alkyl having 1 to 30 carbons, alkoxy having 1 to 30 carbons, alkoxyalkyl having 2 to 30 carbons, fluoromethyl, difluoromethyl, trifluoromethyl, fluoromethoxy, difluoromethoxy or trifluoromethoxy And in these alkyl, alkoxy and alkoxyalkyl, arbitrary —CH ₂ — is represented by difluoromethylene or general formula (XIV). Ring B and ring C are independently 1,4-phenylene or 1,4-cyclohexylene; f, g and h are independently integers from 0 to 4; i, j and k are each independently an integer of 0 to 3, and their sum is 1 or more; l and m are independently 1 or 2.

In the general formula (XIV), R ¹⁹ , R ²⁰ , R ²¹ and R ²² are independently alkyl having 1 to 10 carbons or phenyl, and n is an integer of 1 to 100.

[14] The diamine of component B is represented by the following general formulas (VIII-2), (VIII-4), (VIII-5), (VIII-6), (XI-1), (XI-2) and (XI). [XI] The liquid crystal aligning agent according to [13], which is a diamine represented by a general formula selected from the group consisting of XI-6).

In the general formula, R ²³ independently represents an alkyl having 3 to 30 carbon atoms or an alkoxy having 3 to 30 carbon atoms, R ²⁹ represents hydrogen or an alkyl group having 1 to 30 carbon atoms, and R ³⁰ represents Represents hydrogen or an alkyl group having 1 to 20 carbon atoms.

[15] The liquid crystal aligning agent according to any one of [1] to [14], which contains two or more kinds of the polymers.

[16] The liquid crystal aligning agent according to any one of [1] to [15], further comprising an oxirane compound.

[17] A liquid crystal aligning agent comprising a heterocyclic compound having a heterocyclic structure of one or both of thiirane and oxazoline, and a polyamic acid or a derivative thereof,
Containing 1 to 40% by weight of the heterocyclic compound with respect to the polyamic acid or a derivative thereof;
The polyamic acid or derivative thereof is a reaction product obtained by reacting tetracarboxylic dianhydride as an acid component and diamine as an amine component,
The tetracarboxylic dianhydride is one or more compounds selected from the group consisting of the following structural formulas (1), (2), (5) to (7) and (14) as the A component of the acid. And a compound selected from the group consisting of the following structural formulas (19), (23), (25), (35) to (37), (39), (44) and (49) as the B component of the acid One or more of one or both of
The diamine has the following structural formulas (IV-1), (IV-2), (IV-15), (IV-16), (V-1) to (V-12), (V) as the A component of the amine. -33), one or more compounds selected from the group consisting of (VII-1) and (VII-2), and the following general formulas (VIII-2) and (VIII-4) as the B component of the amine One or two or more compounds represented by the general formula selected from the group consisting of: (VIII-5), (VIII-6), (XI-1), (XI-2) and (XI-6) A liquid crystal aligning agent characterized by being one or both of the above.

In the general formula, R ²³ independently represents an alkyl having 3 to 30 carbon atoms or an alkoxy having 3 to 30 carbon atoms, R ²⁹ represents hydrogen or an alkyl group having 1 to 30 carbon atoms, and R ³⁰ represents Represents hydrogen or an alkyl group having 1 to 20 carbon atoms.

[18] The tetracarboxylic dianhydride includes the compound of the structural formula (1) as the A component of the acid and the structural formulas (19), (23), and (49) as the B component of the acid. Any one or both of the compounds selected from the group consisting of: wherein the diamine is the A component of the amine as the structural formulas (IV-16), (V-1), (V-7) and (VII) -2) one or two or more compounds selected from the group consisting of: and the B component of the amine, or both of the heterocyclic compounds are N, N, N ′, N ′, -Composed of tetrakistyranylmethyl-4,4'-diaminodiphenylethane, poly (styrene-co-2-isopropenyloxazoline), and 1,3-bis (4,5-dihydro-2-oxazolyl) benzene From the group The liquid crystal aligning agent according to [17], wherein the at one or more barrel compounds.

[19] The B component of the amine is selected from the group consisting of the general formulas (VIII-2), (VIII-5), (XI-1), (XI-2), and (XI-6). The liquid crystal aligning agent according to [18], which is one or more of compounds represented by the general formula.

[20] The liquid crystal aligning agent according to any one of [17] to [19], further comprising an oxirane compound.

[21] The method according to [20], wherein the oxirane compound is one or both of a phenol-dicyclopentadiene resin type epoxy resin and 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane. Liquid crystal aligning agent.

[22] A liquid crystal alignment film formed by firing the liquid crystal aligning agent according to any one of [1] to [21] in a film state.

[23] A pair of opposed substrates, electrodes formed on one or both of the opposed surfaces of the pair of substrates, and formed on the opposed surfaces of the pair of substrates. A liquid crystal display element having a liquid crystal alignment film and a liquid crystal layer formed between the pair of substrates, wherein the liquid crystal alignment film is the liquid crystal alignment film according to [22]. .

  According to the present invention, it is possible to provide liquid crystal display elements of various driving methods that have a high voltage holding ratio and good long-term reliability.

  The liquid crystal aligning agent of the present invention includes a heterocyclic compound having one or two or more heterocyclic structures selected from the group consisting of oxetane, thiirane, aziridine, and oxazoline, and one or more polyamic acids and derivatives thereof. It is a composition.

<1. Heterocyclic Compound in the Present Invention>
The heterocyclic compound used in the present invention has one or more heterocyclic structures selected from the group consisting of oxetane, thiirane, aziridine, and oxazoline. The said heterocyclic compound may have only 1 type of heterocyclic structure in one compound, and may have 2 or more types. Moreover, the said heterocyclic compound should just have one said heterocyclic structure in one compound, However, It is preferable to have two or more. Further, the heterocyclic compound may be a polymer having a heterocyclic structure in the side chain or a copolymer. The polymer having a heterocyclic structure in the side chain may be a homopolymer of a monomer having a heterocyclic structure in the side chain, a monomer having a heterocyclic structure in the side chain, and a monomer having no heterocyclic structure. The copolymer may be used. The copolymer having a heterocyclic structure in the side chain may be a copolymer of two or more monomers having a heterocyclic structure in the side chain, or two or more monomers having a heterocyclic structure in the side chain. And a copolymer of a monomer having no heterocyclic structure.

  The specific heterocyclic structure has a hetero atom. Although the reason why the liquid crystal aligning agent containing the specific heterocyclic compound is excellent in voltage holding ratio and long-term stability is not clear, a hetero atom and a polyamic acid in a specific heterocyclic structure in the specific heterocyclic compound It seems to be related to the reaction with the carbonyl group inside. Therefore, the specific heterocyclic structure is preferably a structure that exists in a specific heterocyclic compound so that a hetero atom in the specific heterocyclic structure and a carbonyl group of the polyamic acid can react.

  Heterocyclic compounds mainly having oxetane as a heterocyclic structure (hereinafter also referred to as “oxetane compounds”), heterocyclic compounds mainly having thiirane as a heterocyclic structure (hereinafter also referred to as “thiirane compounds”), mainly aziridine A heterocyclic compound having a heterocyclic structure (hereinafter also referred to as “aziridine compound”) and a heterocyclic compound having oxazoline mainly as a heterocyclic structure (hereinafter also referred to as “oxazoline compound”) dissolve polyamic acid and its derivatives. It is preferably soluble in the solvent used.

  As the oxetane compound, EPICLON (trade name, manufactured by Dainippon Ink & Chemicals, Inc.), bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene, bis [(3-ethyl-3-oxetanylmethoxy) methyl -Phenyl] methane, bis [(3-ethyl-3-oxetanylmethoxy) methyl-phenyl] ether, bis [(3-ethyl-3-oxetanylmethoxy) methyl-phenyl] propane, bis [(3-ethyl-3- Oxetanylmethoxy) methyl-phenyl] sulfone, bis [(3-ethyl-3-oxetanylmethoxy) methyl-phenyl] ketone, bis [(3-ethyl-3-oxetanylmethoxy) methyl-phenyl] hexafluoropropane, tri [( 3-ethyl-3-oxetanylmethoxy) methyl] benzene, and Tetra [(3-ethyl-3-oxetanylmethoxy) methyl] benzene. In addition to these, oligomers and polymers having oxetanyl can also be mentioned.

  Examples of thiirane compounds include phenyl glycidyl ether, butyl glycidyl ether, 3,3,3-trifluoromethyl propylene oxide, styrene oxide, hexafluoropropylene oxide, cyclohexene oxide, N-glycidyl phthalimide, (nonafluoro-N-butyl) epoxide, Perfluoroethyl glycidyl ether, epichlorohydrin, epibromohydrin, N, N-diglycidyl aniline, and 3- [2- (perfluorohexyl) ethoxy] -1,2-epoxypropane, ethylene glycol diglycidyl ether , Polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether Ter, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, and 3- (N, N-diglycidyl) aminopropyltrimethoxy Silane, 1,3,5,6-tetraglycidyl-2,4-hexanediol, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidyl Aminomethyl) cyclohexane, N, N, N ′, N ′,-tetraglycidyl-4,4′-diaminodiphenylmethane, and oxygen of the glycidyl group in 3- (N-allyl-N-glycidyl) aminopropyltrimethoxysilane. For example, J. et al. Org. Chem. , 28, 229 (1963), which is substituted with sulfur and the glycidyl group is converted to an ethylene sulfide group.

Examples of the aziridine compound include 2,4,6-tris (1′-aziridinyl) -1,3,5-triazine, ω-aziridinylpropionic acid-2,2-dihydroxymethyl-butanol triester, 6-tris (2-methyl-1-aziridinyl) -1,3,5-triazine, 2,4,6-tris (2-ethyl-1-aziridinyl) -1,3,5-triazine, 4,4 ′ -Bis (ethyleneiminocarbonylamino) diphenylmethane, bis (2-ethyl-1-aziridinyl) benzene-1,3-dicarboxylic acid amide, tris (2-ethyl-1-aziridinyl) benzene-1,3,5-tricarboxylic acid Amide, bis (2-ethyl-1-aziridinyl) sebacic acid amide, 1,6-bis (ethyleneiminocarbonylamino) hexane, 2,4-die Tylene ureidotoluene, 1,1'-carbonyl-bis-ethyleneimine, polymethylene-bis-ethyleneurea (C2-C4), and N, N'-bis (4,6-diethyleneimino-1,3,5-triazine -2-yl) -hexamethylenediamine. In addition to these, oligomers and polymers having aziridinyl can also be mentioned.

  As the oxazoline compound, 2,2′-bis (2-oxazoline), 1,2,4-tris- (2-oxazolinyl-2) -benzene, 4-furan-2-ylmethylene-2-phenyl-4H-oxazole -5-one, 1,4-bis (4,5-dihydro-2-oxazolyl) benzene, 1,3-bis (4,5-dihydro-2-oxazolyl) benzene, 2,3-bis (4-iso Propenyl-2-oxazolin-2-yl) butane, 2,2′-bis-4-benzyl-2-oxazoline, 2,6-bis (isopropyl-2-oxazolin-2-yl) pyridine, 2,2′- Isopropylidenebis (4-tert-butyl-2-oxazoline), 2,2′-isopropylidenebis (4-phenyl-2-oxazoline), 2,2′-methylenebis (4 tert- butyl-2-oxazoline), and 2,2'-methylenebis (4-phenyl-2-oxazoline) and the like. In addition to these, polymers and oligomers having oxazolyl such as Epocross (trade name, manufactured by Nippon Shokubai Co., Ltd.) can also be mentioned.

<2. Polymer in the Present Invention>
The polymer in the present invention is one or more polymers selected from polyamic acid and derivatives thereof. The polyamic acid is a reaction product obtained by reacting tetracarboxylic dianhydride as an acid component and diamine as an amine component. In the present invention, such a polyamic acid can be used.

  Further, the polyamic acid in the present invention may contain a derivative thereof. The derivative of the polyamic acid is a form dissolved in a solvent when the liquid crystal aligning agent described later is used, and when the liquid crystal aligning agent is used as a liquid crystal aligning film described later, a liquid crystal aligning film mainly composed of polyimide is used. It is a component that can be formed. Examples of such polyamic acid derivatives include soluble polyimides, polyamic acid esters, polyamic acid amides, and the like. More specifically, 1) polyimide in which all amino acids and carboxyls of polyamic acid are subjected to a dehydration ring-closing reaction, 2) Partially dehydrated ring-closing partial polyimide, 3) Polyamic acid ester in which carboxyl of polyamic acid is converted to ester, 4) Part of acid dianhydride contained in tetracarboxylic dianhydride compound is organic dicarboxylic A polyamic acid-polyamide copolymer obtained by reacting with an acid, and 5) a polyamideimide obtained by subjecting a part or all of the polyamic acid-polyamide copolymer to a dehydration ring-closing reaction.

  The polyamic acid and its derivative can be obtained by reaction of tetracarboxylic dianhydride and diamine. One or more tetracarboxylic dianhydrides are used as the tetracarboxylic dianhydride in the present invention, but a part of the tetracarboxylic dianhydride may be replaced with a dicarboxylic acid. Here, the ratio of the dicarboxylic acid to the tetracarboxylic dianhydride is preferably 10 mol% or less.

  One or two or more diamines are used as the diamine in the present invention, but a part of the diamine may be replaced with a monoamine. Here, the ratio of monoamine to diamine is preferably 10 mol% or less.

  The tetracarboxylic dianhydride is arbitrarily selected. For example, 1) an aromatic tetracarboxylic dianhydride used as an A component of an acid, and 2) an aliphatic tetracarboxylic dianhydride and fat used as a B component of an acid. Any one or two or more of cyclic tetracarboxylic dianhydrides are preferably mentioned.

In order to use the polyamic acid in the present invention as a component of the liquid crystal aligning agent,
It is preferable to take a form soluble in a solvent. In order to make the polyamic acid in the present invention in such a soluble form, it is preferable to appropriately select a tetracarboxylic dianhydride used as an acid component.

  Here, as the 1) aromatic tetracarboxylic dianhydride used as the A component of the acid, for example, acid dianhydrides represented by the following structural formulas (1) to (18) are exemplified. Of the following aromatic tetracarboxylic dianhydrides, acid dianhydrides represented by structural formulas (1), (2), (5), (6), (7), and (14) are more preferable. Most preferred is pyromellitic dianhydride represented by the structural formula (1).

  Examples of the 2) aliphatic tetracarboxylic dianhydride or alicyclic tetracarboxylic dianhydride used as the B component of the acid include, for example, acid dianhydrides represented by the following structural formulas (19) to (67). Things are specifically exemplified.

Among the tetracarboxylic dianhydrides, acid dianhydrides represented by structural formulas (19) to (39), (44), and (49) are preferable, and structural formula (19) is more preferable. ), (23), (25), (35), (36), (37), (39), (44) and (49), and more preferred are structural dianhydrides. And acid dianhydrides represented by (19), (23) and (49), and particularly preferably 1, 2 represented by the structural formula (19).
3,4-cyclobutanetetracarboxylic dianhydride.

  Moreover, in order to make the polyamic acid in this invention into a polyimide soluble in a solvent, it is represented by structural formula (24), (35)-(44), (49), (50), (53), (60). It is preferable to use acid dianhydride.

  As the tetracarboxylic dianhydride in the present invention, the tetracarboxylic dianhydrides represented by the structural formulas (1) to (67) can be used singly or in combination of two or more. . Aromatic tetracarboxylic dianhydride and aliphatic tetracarboxylic dianhydride or alicyclic tetracarboxylic dianhydride (particularly preferably pyromellitic dianhydride, 1,2,3,4-cyclobutanetetra A liquid crystal alignment film formed using a liquid crystal aligning agent containing a polyamic acid synthesized from a tetracarboxylic dianhydride in the present invention using a carboxylic acid dianhydride) is a liquid crystal display element including the same. Particularly good voltage holding ratio can be given.

  Furthermore, other tetracarboxylic dianhydrides other than the tetracarboxylic dianhydrides represented by the structural formulas (1) to (67) can be used for the tetracarboxylic dianhydrides in the present invention. Other tetracarboxylic dianhydrides are optional, but examples include tetracarboxylic dianhydrides having a side chain structure. The liquid crystal aligning film formed using the liquid crystal aligning agent containing the polyamic acid synthesize | combined from the tetracarboxylic dianhydride in this invention using the tetracarboxylic dianhydride which has a side chain structure contains it The pretilt angle in the liquid crystal display element can be increased.

  The tetracarboxylic dianhydride having a side chain structure is not particularly limited, but those having a steroid skeleton represented by the following structural formulas (68) and (69) can be preferably used in the present invention.

  The other tetracarboxylic dianhydrides that can be used in the tetracarboxylic dianhydride according to the present invention are not limited to the tetracarboxylic dianhydrides described above, and the scope of achieving the object of the present invention. It goes without saying that various other forms of tetracarboxylic dianhydride are present. Such further other tetracarboxylic dianhydrides may be used singly or in combination of two or more.

  Moreover, a part of tetracarboxylic dianhydride used for the tetracarboxylic dianhydride in the present invention may be replaced with a carboxylic anhydride. By replacing a part of tetracarboxylic dianhydride with carboxylic anhydride, the termination of polymerization reaction can be caused, and further progress of the reaction can be suppressed, so the resulting polymer (polyamic acid) The molecular weight of can be easily controlled. The ratio of the carboxylic acid anhydride to the tetracarboxylic dianhydride may be in a range that does not impair the effects of the present invention, but as a guideline, it is preferably 10 mol% or less of the total amine amount.

  As above-mentioned, the polyamic acid contained in the liquid crystal aligning agent of this invention is obtained by making tetracarboxylic dianhydride and diamine react.

  Although the said diamine is selected arbitrarily, Preferably the diamine represented by general formula (I)-(VII) is mentioned.

In the general formula (I), A ¹ is, - (CH _{2) m} - represents a. Here, m represents an integer of 1 to 12. In general formulas (III), (V), and (VII), A ¹ is independently a single bond, —O—, —S—, —SS—, —SO ₂ —, —CO—, — CONH -, - NHCO -, - C (CH 3) 2 -, - C (CF 3) 2 -, - (CH 2) m -, - O- (CH 2) m -O-, or -S- ( CH ₂₎ represents an _m -S-. Here, m represents an integer of 1 to 12. In general formula (VI), A ² is independently a single bond, —O—, —S—, —CO—, —C (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ —, or carbon number. 1-6 alkylene is represented. Hydrogen which is further coupled to the general formula (II) ~ (VII) cyclohexane ring or a benzene ring in the, -F _{independently, -CH 3, -OH, -COOH,} -SO 3 H, -PO 3 H ₂ , may be replaced with benzyl or 4-hydroxybenzyl.

  Examples of the diamine represented by the general formula (I) include diamines represented by structural formulas (I-1) to (I-4).

  Examples of the diamine represented by the general formula (II) include diamines represented by the structural formulas (II-1) and (II-2).

  Examples of the diamine represented by the general formula (III) include diamines represented by structural formulas (III-1) to (III-3).

  Examples of the diamine represented by the general formula (IV) include diamines represented by structural formulas (IV-1) to (IV-16).

  Examples of the diamine represented by the general formula (V) include diamines represented by structural formulas (V-1) to (V-33).

  Examples of the diamine represented by the general formula (VI) include diamines represented by structural formulas (VI-1) to (VI-6).

  Examples of the diamine represented by the general formula (VII) include diamines represented by structural formulas (VII-1) to (VII-16).

  Of these, the structural formulas (IV-1) to (IV-5), (IV-15), (IV-16), (V-1) to (V-12), (V-26) are more preferable. ), (V-27), (V-31), (V-33), (VI-1), (VI-2), (VI-6), (VII-1) to (VII-5) Most preferred are structural formulas (IV-1), (IV-2), (IV-15), (IV-16), (V-1) to (V-12), ( V-33), (VII-1), and the diamine represented by (VII-2) are mentioned.

The diamine in this invention may use the diamine represented by the said general formula (I)-(VII) individually by 1 type, and may use 2 or more types. The molar ratio of the diamine represented by the general formulas (I) to (VII) of the diamine in the present invention is determined by the structure of the selected diamine represented by the general formulas (I) to (VII) and the desired voltage. What is necessary is just to adjust according to a holding | maintenance rate, it is preferable that it is 1-100%, and it is more preferable that it is 5-80%.

  As described above, one or two or more diamines are used as the diamine in the present invention. In particular, applications where a large pretilt angle is required, such as VA liquid crystal display elements, OCB liquid crystal display elements, STN liquid crystal display elements, and the like. Then, it is preferable to use a diamine having a side chain structure.

  In this specification, a diamine having a side chain structure is a substituent (side chain) branched from the main chain and capable of expressing a desired pretilt angle when the substituent connecting two amino groups is the main chain. ). That is, a diamine having a side chain structure reacts with tetracarboxylic dianhydride to provide a polyamic acid or polyimide (branched polyamic acid or branched polyimide) having a side chain group with respect to the polymer main chain. Can do. A liquid crystal alignment film formed from a liquid crystal alignment agent containing a polyamic acid or a polyimide having a side chain group with respect to such a polymer main chain can increase the pretilt angle in the liquid crystal display element. This is described in, for example, Patent Document 1 (Japanese Patent Laid-Open No. 11-193345).

Therefore, the side chain in the diamine having a side chain structure may be appropriately selected according to the required pretilt angle. For example, the side chain is preferably a group having 3 or more carbon atoms. In particular,
1) phenyl which may have a substituent, cyclohexylphenylene which may have a substituent, bis (cyclohexyl) phenylene which may have a substituent, alkyl having 3 or more carbon atoms, alkenyl or Alkynyl,
2) phenyloxy which may have a substituent, cyclohexyloxy which may have a substituent, bis (cyclohexyl) oxy which may have a substituent, which may have a substituent Phenylcyclohexyloxy, optionally substituted cyclohexylphenyloxy, or alkyloxy, alkenyloxy or alkynyloxy having 3 or more carbon atoms,
3) Phenylcarbonyl, or alkylcarbonyl, alkenylcarbonyl or alkynylcarbonyl having 3 or more carbon atoms,
4) Phenylcarbonyloxy, or alkylcarbonyloxy, alkenylcarbonyloxy or alkynylcarbonyloxy having 3 or more carbon atoms,
5) phenyloxycarbonyl which may have a substituent, cyclohexyloxycarbonyl which may have a substituent, bis (cyclohexyl) oxycarbonyl which may have a substituent, which has a substituent Bis (cyclohexyl) phenyloxycarbonyl which may be substituted, cyclohexylbis (phenyl) oxycarbonyl which may have a substituent, or alkyloxycarbonyl having 3 or more carbon atoms, alkenyloxycarbonyl or alkynyloxycarbonyl,
6) phenylaminocarbonyl, or alkylaminocarbonyl having 3 or more carbon atoms, alkenylaminocarbonyl or alkynylaminocarbonyl,
7) Cyclic alkylene having 3 or more carbon atoms,
8) Cycloalkylalkylene which may have a substituent, phenylalkylene which may have a substituent, bis (cyclohexyl) alkylene which may have a substituent, which may have a substituent Cyclohexyl phenylalkylene, optionally substituted bis (cyclohexyl) phenylalkylene, optionally substituted phenylalkyloxy, alkylphenyloxycarbonyl, or alkylbiphenylyloxycarbonyl,
9) phenyl or cyclohexyl substituted by alkyl, fluorine-substituted alkyl, or alkoxy, and
10) Alkyl or fluorine in which two or more benzene rings or cyclohexane rings are bonded through a single bond, or bonded through —O—, —COO—, —OCO—, —CONH—, or alkylene having 1 to 3 carbon atoms. Examples include, but are not limited to, a substituted alkyl group, a ring assembly group substituted by alkoxy, or a group having a steroid skeleton.

  Here, examples of the “substituent” include alkyl, alkoxy, alkoxyalkyl and the like.

  Moreover, bis (cyclohexyl) or bis (phenyl) may be interrupted by alkylene.

  In the present specification, the terms “alkyl”, “alkenyl”, and “alkynyl” may be linear or branched.

  Specific examples of the diamine having a side chain structure used in the present invention include diamines represented by general formulas (VIII) and (IX) to (XII).

Here, in the general formula (VIII), R ¹ is a single bond, —O—, —CO—, —COO—, —OCO—, —CONH—, —CH ₂ O—, —CF ₂ O— or (CH ₂ ) _e- , wherein e is an integer of 1 to 6, R ² is a group having a steroid skeleton, a group represented by general formula (XIII), alkyl having 1 to 30 carbons, or phenyl, When the alkyl has 2 to 6 carbon atoms, any —CH ₂ — may be independently replaced by —O— (but not consecutively), —CH═CH— or —C≡C—. Well, and the hydrogen of this phenyl may be independently replaced by fluorine, methyl, methoxy, fluoromethoxy, difluoromethoxy or trifluoromethoxy.

In General Formula (IX), R ³ is independently hydrogen or methyl, R ⁴ is hydrogen or alkyl having 1 to 30 carbons, and R ⁵ is independently a single bond, —CO— or —CH _2. -. In the general formula (X), R ³ is independently hydrogen or methyl, R ⁴ is hydrogen or alkyl having 1 to 30 carbon atoms, and R ⁵ is independently a single bond, —CO— or —CH. ₂ and R ⁶ and R ⁷ are independently hydrogen, alkyl having 1 to 30 carbons, or phenyl.

In the general formula (XI), R ⁸ is hydrogen or alkyl having 1 to 30 carbon atoms, and any —CH ₂ — of the alkyl is independently —O— (but not consecutively), —CH═ CH ⁹ may be replaced by CH— or —C≡C—, R ⁹ is independently —O— or alkylene having 1 to 6 carbon atoms, and ring A is 1,4-phenylene or 1,4-cyclohexylene. Where a is 0 or 1, b is 0, 1 or 2, and c is independently 0 or 1.

In General Formula (XII), R ¹⁰ is alkyl having 3 to 30 carbons or fluorinated alkyl having 3 to 30 carbons, and R ¹¹ is hydrogen, alkyl having 1 to 30 carbons, or 1 to 30 carbons. R ¹² is independently —O— or alkylene having 1 to 6 carbons, and d is independently 0 or 1.

In the general formula (XIII), R ¹³ , R ¹⁴ and R ¹⁵ are each independently a single bond, —O—, —COO—, —OCO—, —CONH—, alkylene having 1 to 4 carbons, 3 oxyalkylene, or alkyleneoxy having 1 to 3 carbon atoms (provided that oxygen is not continuously bonded); R ¹⁶ and R ¹⁷ are independently hydrogen, fluorine or methyl; R ¹⁸ is hydrogen, fluorine Chlorine, cyano, alkyl having 1 to 30 carbons, alkoxy having 1 to 30 carbons, alkoxyalkyl having 2 to 30 carbons, fluoromethyl, difluoromethyl, trifluoromethyl, fluoromethoxy, difluoromethoxy or trifluoromethoxy And any —CH ₂ — in these alkyls, alkoxys and alkoxyalkyls is difluoromethylene or a group represented by the general formula (XIV) Ring B and ring C are independently 1,4-phenylene or 1,4-cyclohexylene; f, g and h are independently integers from 0 to 4; i, j And k are each independently an integer of 0 to 3, and their sum is 1 or more; l and m are independently 1 or 2.

Here, in the general formula (XIV), R ¹⁹ , R ²⁰ , R ²¹ and R ²² are independently alkyl having 1 to 10 carbons or phenyl, and n is an integer of 1 to 100.

  Examples of the diamine represented by the general formula (VIII) include diamines represented by the following general formulas or structural formulas (VIII-1) to (VIII-43).

In General Formulas (VIII-1) to (VIII-11), R ²³ is preferably alkyl having 3 to 30 carbons or alkoxy having 3 to 30 carbons, and alkyl having 5 to 25 carbons or having 5 to 25 carbons. More preferred is alkoxy. R ²⁴ is preferably alkyl having 1 to 30 carbons or alkoxy having 1 to 30 carbons, more preferably alkyl having 3 to 25 carbons or alkoxy having 3 to 25 carbons.

In the general formulas (VIII-12) to (VIII-15), R ²⁵ is preferably alkyl having 4 to 30 carbons, and more preferably alkyl having 6 to 25 carbons. In general formulas (VIII-16) and (VIII-17), R ²⁶ is preferably an alkyl having 6 to 30 carbon atoms, more preferably an alkyl having 8 to 25 carbon atoms.

In the general formulas (VIII-18) to (VIII-37), R ²⁷ is preferably alkyl having 1 to 30 carbons and alkoxy having 1 to 30 carbons, and alkyl having 3 to 25 carbons or 3 to 25 carbons. More preferred is alkoxy. R ²⁸ is -H, -F, alkyl having 1 to 30 carbon atoms, alkoxy having 1 to 30 carbon atoms, -CN, are -OCH ₂ F, -OCHF ₂ or -OCF ₃ preferably alkyl of 3 to 25 carbon atoms Alternatively, alkoxy having 3 to 25 carbon atoms is more preferable.

  Among these, Preferably, the diamine represented by general formula (VIII-1)-(VIII-11) is mentioned. More preferably, the diamine represented by general formula (VIII-2), (VIII-4), (VIII-5), (VIII-6) is mentioned.

In the general formula (IX), one of the two “NH ₂ —Ph—R ⁵ —O—” is preferably bonded to the 3-position of the steroid nucleus and the other is bonded to the 6-position. The two amino groups are each bonded to a phenyl ring carbon, and preferably bonded to meta or para with respect to the bonding position of R ⁵ .

Examples of the diamine represented by the general formula (IX) include structural formulas (IX-1) to (IX-4).
The diamine represented by this is mentioned.

In the general formula (X), the two “NH ₂ — (R ⁷ —) Ph—R ⁵ —O—” are each bonded to the carbon of the phenyl ring, preferably the carbon to which the steroid nucleus is bonded. To the meta or para carbon. The two amino groups are each bonded to a phenyl ring carbon, but are preferably bonded to meta or para to R ⁵ .

  Examples of the diamine represented by the general formula (X) include diamines represented by structural formulas (X-1) to (X-8).

In the general formula (XI), the two amino groups are each bonded to carbon of the phenyl ring, but are preferably bonded to meta or para to R ⁹ .

  Examples of the diamine represented by the general formula (XI) include diamines represented by the general formulas (XI-1) to (XI-8).

In general formulas (XI-1) to (XI-3), R ²⁹ is preferably —H and an alkyl group having 1 to 30 carbon atoms. In general formulas (XI-4) to (XI-8), R ³⁰ is -H and an alkyl group having 1 to 20 carbon atoms are preferred.

In the general formula (XII), the two amino groups are each bonded to carbon of the phenyl ring, but are preferably bonded to meta or para with respect to R ¹² .

  Examples of the diamine represented by the general formula (XII) include diamines represented by the general formulas (XII-1) to (XII-3).

In general formulas (XII-1) to (XII-3), R ³¹ is preferably an alkyl group having 6 to 20 carbon atoms, and R ³² is preferably —H and an alkyl group having 1 to 10 carbon atoms.

  As the diamine in the present invention, the diamines represented by the general formulas (VIII) to (XII) may be used singly or in combination of two or more. The molar ratio of the diamine having a side chain structure in the diamine according to the present invention may be adjusted according to the structure of the diamine having the selected side chain structure and the desired pretilt angle, and is preferably 1 to 100%. 10 to 100% is more preferable.

  Furthermore, the diamine in the present invention includes diamines other than the diamines represented by the general formulas (I) to (VII) and the side chain structures represented by the general formulas (VIII) to (XII). Can be used. Such other diamines are optional, for example, naphthalene diamine having a naphthalene structure, fluorene diamine having a fluorene structure, siloxane diamine having a siloxane bond, or other than general formulas (VIII) to (XII) A diamine having a side chain structure of

  The siloxane-based diamine is not particularly limited, but those represented by the following general formula (XV) can be preferably used in the present invention.

In general formula (XV), R ³³ and R ³⁴ independently represent alkyl or phenyl having 1 to 3 carbon atoms, and A ³ independently represents methylene, phenylene or alkyl-substituted phenylene. l represents an integer of 1 to 6, and m represents an integer of 1 to 10.

  Further, other diamines are not particularly limited, but those represented by, for example, the following general formulas (1 ') to (8') can be preferably used in the present invention.

In general formulas (1 ′) to (8 ′), R ³⁵ and R ³⁶ independently represent an alkyl group having 3 to 30 carbon atoms.

  The other diamines other than the general formulas (I) to (XII) used for the diamine in the present invention are not limited to the diamine, and various other diamines can be used as long as the object of the present invention is achieved. Needless to say, a diamine of the form Moreover, the said other diamine can be used individually by 1 type or in combination of 2 or more types.

  The diamine in the present invention can give a suitable pretilt angle to the liquid crystal alignment film formed using the liquid crystal aligning agent of the present invention by appropriately selecting the type of diamine and the combination thereof.

  In the case of a VA type liquid crystal display element, a large pretilt angle of about 80 to 90 °, and in the case of an OCB type liquid crystal display element, a pretilt angle of about 7 to 20 ° has a TN type liquid crystal display element or STN type liquid crystal display element. In this case, a pretilt angle of about 3 to 10 ° is often required, and in the case of an IPS liquid crystal display element, a small pretilt angle of about 0 to 3 ° is often required. Therefore, the liquid crystal aligning agent of the present invention in which the pretilt angle can be appropriately adjusted using a diamine having a side chain structure can be applied to any kind of liquid crystal display element.

As described above, a part of the diamine used for the diamine in the present invention may be replaced with a monoamine. By substituting a part of the diamine with a monoamine, the termination of the polymerization reaction can be caused, and further progress of the reaction can be suppressed, so the molecular weight of the resulting polymer (polyamic acid) can be easily controlled. Can do. The ratio of the monoamine to the diamine may be in a range that does not impair the effects of the present invention, but as a guideline, it is preferably 10 mol% or less of the total amine amount.

The liquid crystal aligning agent of the present invention preferably further contains an oxirane compound from the viewpoint of suppressing deterioration of storage characteristics in the liquid crystal display element of the present invention. The oxirane compound is a compound having one or more oxiranyls. The oxirane compound may be a polymer. In the case of a polymer, the oxirane compound may be a homopolymer or a copolymer.

Examples of the oxirane compound include ether-type oxirane compounds, alicyclic oxirane compounds, ester-type oxirane compounds, amine-type oxirane compounds, heterocyclic oxirane compounds, silane-type oxirane compounds, and oxiranyl group-containing acrylic compounds. As the oxirane compound, one or more of these oxirane compounds can be used.

  Examples of commercially available ether type oxirane compounds include Epicoat 1001, 1002, 1003, 1004, 1007, 1009, and 1010 (manufactured by Yuka Shell Epoxy Co., Ltd.), and Epikote 807 (Okay Shell Epoxy Co., Ltd.). )), Epicron HP-7200HH, EXA-7260HH (Dainippon Ink Co., Ltd.); Alicyclic oxirane compounds commercially available as, for example, CY-175, 177, 179 (CIBA-GEIGY) ERL-4234, 4299, 4221, 4206 (UCC); commercially available ester-type oxirane compounds include, for example, Shodyne 508 (manufactured by Showa Denko KK), Araldite CY-182 192, 184 (manufactured by CIBA-GEIGY), Epicoat 871, 8 2 (Oilized Shell Epoxy Co., Ltd.), ED-5661, 5562 (Celanese Coating Co., Ltd.); Examples of amine type oxirane compounds include tetraglycidyldiaminodiphenylmethane, triglycidyl-para-aminophenol, tri Glycidyl-meta-aminophenol, diglycidyl aniline, diglycidyl toluidine, tetraglycidyl metaxylylene diamine, diglycidyl tribromaniline, tetraglycidyl bisaminomethylcyclohexane; -GEIGY), Epikote RXE-15 (Oilized Shell Epoxy Co., Ltd.), EPITEC (Nissan Chemical Co., Ltd.); Examples of silane type oxirane compounds include (3-glycidoxy) Cypropyl) trimethoxysilane, (3-glycidoxypropyl) methyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 5,6-epoxyhexyltriethoxysilane, (3-glycidoxypropyl ) Dimethylethoxysilane, (3-glycidoxypropyl) methyldiethoxysilane, and the like.

Other examples of the oxirane compound include phenyl glycidyl ether, butyl glycidyl ether, 3,3,3-trifluoromethyl propylene oxide, styrene oxide, hexafluoropropylene oxide, cyclohexene oxide, N-glycidyl phthalimide, (nonafluoro-N -Butyl) epoxide, perfluoroethylglycidyl ether, epichlorohydrin, epibromohydrin, N, N-diglycidylaniline, and 3- [2- (perfluorohexyl) ethoxy] -1,2-epoxypropane, Ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene group Coal diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, and 3- (N, N-diglycidyl) amino Propyltrimethoxysilane, 1,3,5,6-tetraglycidyl-2,4-hexanediol, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N -Diglycidylaminomethyl) cyclohexane, N, N, N ′, N ′,-tetraglycidyl-4,4′-diaminodiphenylmethane, 3- (N-allyl-N-glycidyl) aminopropyltrimethoxysilane, and the like. It is done.

The polyamic acid and its derivative in the present invention can have any weight average molecular weight. The weight average molecular weight of the polyamic acid and its derivative is not particularly limited, but when used as a component of a liquid crystal aligning agent, it is preferably 5 × 10 ³ or more, and more preferably 1 × 10 ⁴ or more. The polyamic acid having a weight average molecular weight of 5 × 10 ³ or more and its derivative do not evaporate in the step of baking the liquid crystal alignment film, and have preferable physical properties as a component of the liquid crystal alignment agent.

  Here, the weight average molecular weight of the polyamic acid and its derivative is measured by a gel permeation chromatography (GPC) method. For example, the obtained polyamic acid and its derivative are diluted with dimethylformamide (DMF) so that the polyamic acid concentration is about 1% by weight, and DMF is used as a developing solvent using Chromatopack C-R7A (manufactured by Shimadzu Corporation). As measured by gel permeation chromatographic analysis (GPC) and converted to polystyrene. Furthermore, in order to perform GPC measurement of polyamic acid, polyacrylic acid, etc. with high accuracy, a developing solvent in which inorganic acid such as phosphoric acid, hydrochloric acid, nitric acid, sulfuric acid, etc. and inorganic salt such as lithium bromide, lithium chloride, etc. are dissolved in DMF solvent. May be prepared.

  The polyamic acid and its derivative in the present invention can be produced using a known method. For example, in a reaction vessel equipped with a raw material inlet, a nitrogen inlet, a thermometer, a stirrer, and a condenser, one or more of the diamines represented by the general formulas (I) to (XII) and optionally other diamines One or two or more diamines selected from the above, and a desired amount of monoamine as necessary.

  Next, a solvent (for example, N-methyl-2-pyrrolidone or dimethylformamide, which is an amide polar solvent) and one or more of tetracarboxylic dianhydrides, and a carboxylic anhydride as necessary are added. . At this time, it is preferable that the total charge amount of tetracarboxylic dianhydride is approximately equal to the total number of moles of diamine (molar ratio of about 0.9 to 1.1).

  A polyamic acid solution can be obtained by reacting at a temperature of 0 to 70 ° C. for 1 to 48 hours under stirring. Moreover, the polyamic acid with a small molecular weight can also be obtained by heating and raising reaction temperature (for example, 50-80 degreeC).

  The polyamic acid in the present invention can be identified by precipitating with a large amount of a poor solvent, completely separating the solid and the solvent by filtration or the like, and analyzing by IR or NMR. Furthermore, after decomposing solid polyamic acid with an aqueous solution of strong alkali such as KOH or NaOH, the monomer used can be identified by extracting with an organic solvent and analyzing by GC, HPLC or GC-MS. it can.

  The obtained polyamic acid solution can be used after being diluted with a solvent in order to adjust to a desired viscosity.

Further, when the polyamic acid in the present invention is a soluble polyimide that is a polyamic acid derivative, the polyamic acid solution is prepared by using a dehydrating agent such as acetic anhydride, propionic anhydride, anhydrous trifluoroacetic acid, and the like, and dehydrating ring closure. It can be obtained by imidization reaction at a temperature of 20 to 150 ° C. with a tertiary amine such as triethylamine, pyridine, collidine and the like as a catalyst.

  Alternatively, polyamic acid is precipitated from a polyamic acid solution using a large amount of poor solvent (alcohol solvent or glycol solvent such as methanol, ethanol, isopropanol), and the precipitated polyamic acid is dissolved in a solvent such as toluene or xylene. It can also be obtained by carrying out an imidization reaction at a temperature of 20 to 150 ° C. together with the same dehydrating agent and dehydrating ring closure catalyst as described above.

  In the imidization reaction, the ratio of the dehydrating agent to the dehydrating ring-closing catalyst is preferably 0.1 to 10 (molar ratio). The total amount used of both is preferably 1.5 to 10 times the total molar amount of acid dianhydride contained in the tetracarboxylic dianhydride used. By adjusting the dehydrating agent, catalyst amount, reaction temperature and reaction time of this chemical imidization, the degree of imidization can be controlled to obtain a partial polyimide.

  The obtained partial polyimide can be separated from the solvent and re-dissolved in the solvent described later together with the heterocyclic compound described above as a liquid crystal aligning agent, or the heterocyclic compound without being separated from the solvent. Can also be used as a liquid crystal aligning agent.

  As described above, a part of the acid dianhydride used for the tetracarboxylic dianhydride in the present invention may be replaced with an organic dicarboxylic acid. If the polyamic acid in this invention is manufactured using organic dicarboxylic acid and tetracarboxylic dianhydride, a polyamic acid-polyamide copolymer can be obtained. Here, the ratio of the organic dicarboxylic acid to the tetracarboxylic dianhydride may be within a range that does not impair the effects of the present invention, but as a guideline, the ratio is preferably 10 mol% or less.

  Furthermore, polyamideimide can be produced by chemically imidizing the polyamic acid-polyamide copolymer.

<3. Liquid crystal aligning agent of the present invention>
The liquid crystal aligning agent of this invention contains the said heterocyclic compound, the polyamic acid in this invention mentioned above, and its derivative (s). The liquid crystal aligning agent of the present invention may further contain a solvent from the viewpoints of adjusting physical properties such as viscosity, ease of handling, simplification of the process, and the like, and various additives contained in ordinary liquid crystal aligning agents. May further be included.

  The content of the heterocyclic compound in the liquid crystal aligning agent is preferably 0.1 to 50% by weight, and preferably 1 to 40% by weight, based on the weight of the polyamic acid and its derivative in the liquid crystal aligning agent. More preferably, it is more preferably 1 to 20% by weight from the viewpoint of long-term stability of electrical characteristics when used in a liquid crystal display element.

  The content of the heterocyclic structure in the liquid crystal aligning agent in the heterocyclic compound varies depending on the type of the heterocyclic structure. The content of the oxetane compound in the liquid crystal aligning agent is preferably 0.1 to 40% by weight with respect to the polyamic acid and its derivative when the oxetane structure in the oxetane compound is converted to oxetane. Moreover, it is preferable that content of the thiirane compound in a liquid crystal aligning agent is 0.1 to 40 weight% with respect to polyamic acid and its derivative (s) when the thiirane structure in a thiirane compound is converted into thiirane. Moreover, it is preferable that content of the aziridine compound in a liquid crystal aligning agent is 0.1 to 40 weight% with respect to polyamic acid and its derivative (s) when the aziridine structure in an aziridine compound is converted into aziridine. Moreover, it is preferable that content of the oxazoline compound in a liquid crystal aligning agent is 0.1 to 40 weight% with respect to polyamic acid and its derivative (s) when the oxazoline structure in an oxazoline compound is converted into oxazoline.

  In addition, when a heterocyclic compound contains 2 or more types of heterocyclic structures, content of the heterocyclic structure in a liquid crystal aligning agent is calculated | required according to the ratio of each heterocyclic structure in a heterocyclic compound.

  The viewpoint that the content of the oxirane compound in the liquid crystal aligning agent of the present invention is 1 to 20% by weight with respect to polyamic acid and derivatives thereof in terms of oxiranyl is to suppress deterioration of storage characteristics in the liquid crystal display element of the present invention To preferred.

The polyamic acid and derivatives thereof described above can be used for the polyamic acid and derivatives thereof in the present invention. For example, in the case of a polyamic acid, a polyamic acid obtained by reacting the A component or B component of the acid with the A component or B component of the amine, the A component and B component of the acid, and the A component or B of the amine. Polyamic acid obtained by reacting components, polyamic acid obtained by reacting A component or B component of the acid with A component and B component of the amine, and A and B components of the acid and the amine And polyamic acid obtained by reacting the A component and the B component.

  The content rate of the polyamic acid and its derivative in the liquid crystal aligning agent of this invention can be suitably selected with the coating method to the board | substrate of a liquid crystal aligning agent. For example, the polyamic acid in the liquid crystal aligning agent used in a printing machine (including an offset printing machine and an inkjet printing machine, hereinafter may be abbreviated as “printing machine”) used in a manufacturing process of a normal liquid crystal display element, and The content of the derivative is preferably 0.5 to 30% by weight in total, and more preferably 1 to 15% by weight. However, the content is appropriately determined in relation to the viscosity (described later) of the liquid crystal aligning agent. Adjusted.

The solvent used in the present invention includes a wide variety of solvents usually used in the production process and applications of polymer components such as polyamic acid, soluble polyimide, and polyamideimide, and can be appropriately selected depending on the purpose of use. The solvent is a mixed solvent containing 1) an aprotic polar organic solvent that is easily soluble in polyamic acid and soluble polyimide, and 2) a solvent for improving the coatability by changing the surface tension. Is preferred.
Examples of these solvents are as follows.

  1) Aprotic polar organic solvent which is a good solvent for polyamic acid and soluble polyimide (hereinafter, aprotic polar organic solvent): for example, N-methyl-2-pyrrolidone, dimethylimidazolidinone, N-methylcaprolactam, N-methylpropionamide, N, N-dimethylacetamide, dimethyl sulfoxide, N, N-dimethylformamide, N, N-diethylformamide, diethylacetamide, γ-butyrolactone, and γ-valerolactone. Of these, N-methyl-2-pyrrolidone, dimethylimidazolidinone, γ-butyrolactone, γ-valerolactone, and the like are more preferred.

2) Solvents for improving coating properties by changing surface tension (hereinafter referred to as other solvents): for example, ethylene glycol such as alkyl lactate, 3-methyl-3-methoxybutanol, tetralin, isophorone, ethylene glycol monobutyl ether Monoalkyl ether, diethylene glycol monoalkyl ether such as diethylene glycol monoethyl ether, ethylene glycol monoalkyl or phenyl acetate, propylene glycol monoalkyl ether such as triethylene glycol monoalkyl ether, propylene glycol monobutyl ether, dialkyl malonate such as diethyl malonate Dipropylene glycol monoalkyl ether such as dipropylene glycol monomethyl ether, ester compounds such as these acetates That. Of these, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, and the like are more preferred.

  The types and ratios of the aprotic polar solvent and the other solvent can be appropriately set in consideration of the printability, coatability, solubility, storage stability, and the like of the liquid crystal aligning agent. Aprotic polar solvents are relatively superior in solubility and storage stability to other solvents, and other solvents tend to be excellent in printability and coatability.

  As described above, the liquid crystal aligning agent of the present invention may contain various additives. As various additives, high molecular compounds other than polyamic acid and its derivatives, or low molecular compounds can be selected and used according to each purpose.

  For example, a polymer compound soluble in an organic solvent may be used as an additive, and by adding them, the electrical characteristics and orientation of the liquid crystal alignment film to be formed can be controlled. Examples of the polymer compound include polyamide, polyurethane, polyurea, polyester, polyepoxide, polyester polyol, silicone-modified polyurethane, and silicone-modified polyester.

  Examples of additives for low molecular weight compounds include 1) a surfactant in accordance with the purpose when improvement in coating properties is desired, 2) an antistatic agent when improvement in antistatic properties is required, and 3). A silane coupling agent and a titanium-based coupling agent can be used when it is desired to improve adhesion to the substrate and rubbing resistance, and 4) an imidization catalyst can be used when imidization proceeds at a low temperature.

  Examples of the silane coupling agent include vinyltrimethoxysilane, vinyltriethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, and N- (2-aminoethyl) -3-aminopropyl. Methyltrimethoxysilane, paraaminophenyltrimethoxysilane, paraaminophenyltriethoxysilane, metaaminophenyltrimethoxysilane, metaaminophenyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycyl Sidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyl Pyrtrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propylamine, N, N Examples include '-bis [3- (trimethoxysilyl) propyl] ethylenediamine.

  Examples of the imidization catalyst include aliphatic amines such as trimethylamine, triethylamine, tripropylamine, and tributylamine; aromatics such as N, N-dimethylaniline, N, N-diethylaniline, methyl-substituted aniline, and hydroxy-substituted aniline. Aromatic amines: cyclic amines such as pyridine, methyl substituted pyridine, hydroxy substituted pyridine, quinoline, methyl substituted quinoline, hydroxy substituted quinoline, isoquinoline, methyl substituted isoquinoline, hydroxy substituted isoquinoline, imidazole, methyl substituted imidazole, hydroxy substituted imidazole, etc. It is preferable to add the catalyst. In particular, N, N-dimethylaniline, o-hydroxyaniline, m-hydroxyaniline, p-hydroxyaniline, o-hydroxypyridine, m-hydroxypyridine, p-hydroxypyridine, isoquinoline and the like can be mentioned.

  The addition amount of the silane coupling agent is usually 0 to 10% by weight of the total weight of the polymer, and preferably 0.1 to 3% by weight.

  The addition amount of the imidization catalyst is usually 0.01 to 5 equivalents, preferably 0.05 to 3 equivalents, relative to the carbonyl group of the polyamic acid and its derivative.

  Although the addition amount of another additive changes according to the use, it is 0-30 weight% of the total weight of polyamic acid and its derivative (s) normally, and it is preferable that it is 0.1-10 weight%.

  The viscosity of the liquid crystal aligning agent of the present invention varies depending on the coating method, the concentration of the polyamic acid and its derivative, the type of polyamic acid and its derivative used, and the type and ratio of the solvent. For example, in the case of application by a printing press, it is preferably 5 to 100 mPa · s (more preferably 10 to 80 mPa · s). If it is less than 5 mPa · s, it is difficult to obtain a sufficient film thickness, and if it exceeds 100 mPa · s, printing unevenness may increase. In the case of application by spin coating, 5 to 200 mPa · s (more preferably 10 to 100 mPa · s) is suitable.

  The viscosity of the liquid crystal aligning agent is measured by a rotational viscosity measuring method, and is measured using a rotational viscometer (TVE-20L type manufactured by Toki Sangyo Co., Ltd.) (measurement temperature: 25 ° C.).

  Another preferable form of the liquid crystal aligning agent of the present invention is a composition containing two or more kinds of polyamic acids and derivatives thereof. For example, a liquid crystal aligning agent containing two types of polyamic acids, a polyamic acid obtained by reacting tetracarboxylic dianhydride and a diamine having no side chain structure or a derivative thereof as polyamic acid I, tetracarboxylic acid When polyamic acid obtained by reacting dianhydride and diamine using a diamine having a side chain structure or a derivative thereof is polyamic acid II, the composition of polyamic acid I and polyamic acid II is the polyamic acid described above. Prepared by mixing I and polyamic acid II. The liquid crystal alignment film formed using the liquid crystal aligning agent containing the polyamic acid I can give a favorable voltage holding ratio to the liquid crystal display element containing it. The liquid crystal alignment film formed using the liquid crystal aligning agent containing polyamic acid II can provide a suitable pretilt angle to the liquid crystal display element containing the same.

The weight ratio of the polyamic acid I and the polyamic acid II to be mixed is preferably I / II = 99/1 to 50/50, and more preferably I / II = 95/5 to 80/20. The weight ratio may be appropriately adjusted according to, for example, the required pretilt angle, and the pretilt angle can be increased by increasing the ratio of polyamic acid II. As described above, in the present invention, by including (blending) two or more kinds of the above-described polymers, it is possible to impart preferable characteristics as the liquid crystal alignment agent of the present invention.

<4. Liquid crystal alignment film of the present invention>
The liquid crystal alignment film of the present invention is a liquid crystal alignment film formed by baking the polyamic acid in the liquid crystal aligning agent of the present invention described above in the state of the liquid crystal aligning agent of the present invention.

  The liquid crystal alignment film is, for example, a liquid crystal display element substrate or a measurement substrate such as calcium fluoride or silicon applied to the liquid crystal alignment agent of the present invention. Preferably it can form by heating at 180-280 degreeC. Here, the film thickness of the liquid crystal alignment film is preferably 10 to 300 nm, and more preferably 30 to 100 nm. The liquid crystal alignment film is preferably rubbed.

  The film thickness of the liquid crystal alignment film can be adjusted by the viscosity of the liquid crystal aligning agent and the application method of the liquid crystal aligning agent. The film thickness of the liquid crystal alignment film can be measured by a known film thickness measuring device such as a step meter or an ellipsometer. Furthermore, the components in the liquid crystal alignment film can be analyzed using a normal analysis means such as IR or MS after performing a treatment such as hydrolysis as necessary.

<5. Liquid crystal display element of the present invention>
The liquid crystal display element of the present invention includes 1) a pair of substrates arranged opposite to each other, 2) the liquid crystal alignment film of the present invention formed on the opposed surfaces of each of the pair of substrates, and 3) between the pair of substrates. A liquid crystal layer sandwiched between the two.

  The pair of substrates with electrodes arranged opposite to each other is preferably a transparent substrate (for example, a glass substrate).

  An electrode is provided on the surface of at least one or both of the pair of substrates according to the form of the liquid crystal display element. The electrode is not particularly limited as long as it is an electrode formed on one surface of the substrate. Examples of such electrodes include ITO and metal vapor deposition films. The electrode may be formed on the entire surface of the substrate, or may be formed in a predetermined pattern, for example. The liquid crystal alignment film of the present invention is formed on the surface of the substrate on which the electrode is not provided, and the liquid crystal alignment film of the present invention is formed on the electrode on the substrate on which the electrode is provided. The formation of the liquid crystal alignment film of the present invention is as described above.

  The liquid crystal layer sandwiched between the pair of substrates includes a liquid crystal composition. Here, the liquid crystal composition is not particularly limited, and either a liquid crystal composition having a positive dielectric anisotropy or a liquid crystal composition having a negative dielectric anisotropy may be used depending on the driving mode. it can.

  Examples of preferable liquid crystal compositions having a positive dielectric anisotropy include Japanese Patent No. 3086228, Japanese Patent No. 2635435, Japanese Patent Laid-Open No. 5-501735, Japanese Patent Laid-Open No. 8-157826, Japanese Patent Laid-Open No. 8- No. 231960, JP-A-9-241644 (EP882722A1), JP-A-9-302346 (EP806466A1), JP-A-8-199168 (EP722998A1), JP-A-9-235552, JP-A-9-255556. JP, 9-241643 (EP882711A1), JP 10-204016 (EP844229A1), JP 10-204436, JP 10-231482, JP 2000-087040, JP It is disclosed in 2001-48822 gazette etc. .

  The liquid crystal composition used in the VA liquid crystal display element can be various liquid crystal compositions having negative dielectric anisotropy. Examples of preferred liquid crystal compositions include JP-A-57-141432, JP-A-2-4725, JP-A-4-224858, JP-A-8-40953, JP-A-8-104869, Japanese Laid-Open Patent Publication No. 10-168076, Japanese Laid-Open Patent Publication No. 10-168453, Japanese Laid-Open Patent Publication No. 10-236989, Japanese Laid-Open Patent Publication No. 10-236990, Japanese Laid-Open Patent Publication No. 10-236992, Japanese Laid-Open Patent Publication No. 10-236993, Japanese Laid-open Patent Publication No. -236994, JP-A-10-237000, JP-A-10-237004, JP-A-10-237024, JP-A-10-237035, JP-A-10-237075, JP-A-10-237076 JP, 10-237448, (EP967261A1), JP 10-28787. JP-A-10-287875, JP-A-10-291945, JP-A-11-029581, JP-A-11-080049, JP-A-2000-256307, JP-A-2001-019965, JP 2001-072626 A, JP 2001-192657 A, and the like.

  One or more optically active compounds may be added to the liquid crystal composition having a positive or negative dielectric anisotropy.

Of course, the liquid crystal display element of the present invention may have other members.
For example, in a color display TFT type liquid crystal element using a thin film transistor, a thin film transistor, an insulating film, a protective film, a signal electrode, a pixel electrode, and the like are formed on a first transparent substrate, and the second transparent substrate is formed. A black matrix, a color filter, a planarization film, a pixel electrode, and the like that block light outside the pixel region may be included.

  Further, in a VA liquid crystal display element, in particular, an MVA liquid crystal display element, a minute protrusion called a domain is formed on a first transparent substrate. A spacer may be formed for adjusting the cell gap between the substrates.

  The liquid crystal display element of the present invention can be produced by any method. For example, 1) a step of applying a liquid crystal alignment agent on the two transparent substrates, 2) a step of drying the applied liquid crystal alignment agent, 3 ) A step of performing a heat treatment necessary for dehydration and ring-closing reaction of the dried liquid crystal alignment agent, 4) a step of aligning the obtained alignment film, and 5) after bonding the two substrates together, The liquid crystal is manufactured by a method including a step of encapsulating liquid crystal in the substrate, or a step of dropping the liquid crystal on one substrate and then attaching the liquid crystal to the other substrate.

  As a coating method in the step of applying the liquid crystal aligning agent, a spinner method, a printing method, a dipping method, a dropping method, an ink jet method and the like are generally known. These methods are also applicable in the present invention.

  Further, as a method of the drying step and the step of performing the heat treatment necessary for the dehydration reaction, a method of heat treatment in an oven or an infrared furnace, a method of heat treatment on a hot plate, and the like are generally known. These methods are also applicable in the present invention. The drying step is preferably performed at a relatively low temperature (50 to 140 ° C.) within a range where the solvent can be evaporated. In general, the heat treatment step is preferably performed at a temperature of about 150 to 300 ° C.

  The alignment treatment for the liquid crystal alignment film is usually a rubbing treatment for IPS liquid crystal display elements, OCB liquid crystal display elements, TN liquid crystal display elements, and STN liquid crystal display elements. In many cases, the VA liquid crystal display element is not subjected to the rubbing treatment.

  Next, an adhesive is applied onto one substrate, and the liquid crystal is injected in a vacuum. In the case of the dropping injection method, the liquid crystal is dropped on the substrate before bonding, and then bonded on the other substrate. The liquid crystal display element of the present invention is produced by curing the adhesive used for bonding with heat or ultraviolet rays.

  A polarizing plate (polarizing film), a wave plate, a light scattering film, a driving circuit, and the like may be mounted on the liquid crystal display element of the present invention.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples. In addition, the name of the tetracarboxylic dianhydride used in an Example, diamine, and a solvent may be shown with the following abbreviations.

[Tetracarboxylic dianhydride]
Pyromellitic dianhydride {(1)}: PMDA
1,2,3,4-cyclobutanetetracarboxylic dianhydride {(19)}: CBDA
Butanetetracarboxylic dianhydride {(23)}: BDA
2,3,5-tricarboxycyclopentyl acetic acid dianhydride {(49)}: TCMP

[Diamine]
4,4′-diaminodiphenylmethane {formula (V-1)}: DDM
4,4′-Diaminodiphenylethane {Formula (V-7)}: DET
4,4 ′-[1,3-propanebis (4,1-phenylenemethylene)] bis [benzeneamine] {formula (VII-2)}: BABZP3
2- (Phenylmethyl) -1,4-diaminobenzene {Formula (IV-16)}: PhPDA
5-[[4- (4′-pentyl [1,1′-bicyclohexyl] -4-yl) phenyl] methyl] -1,3-diaminobenzene {formula (VIII-5) / R ²³ = C ₅ H ₁₁ }: 5ChCh
1,1-bis (4 - ((4-aminophenoxy) phenyl)) - 4-n-pentyl cyclohexane {formula ^{(XI-1) / R 29} = C 5 H 11}: 5HBA
1,1-bis (4-((4-aminophenyl) methyl) phenyl) -4-n-heptylcyclohexane {formula (XI-2) / R ²⁹ = C ₇ H ₁₅ }: 7HBZ
1,1-bis [(4 - ((4-aminophenoxy) phenyl)) - 4-n-heptyl-cyclohexylethyl] cyclohexane {formula ^{(XI-6) / R 30} = C 7 H 15}: 7H2HBA

[Thirane compound]
N, N, N ′, N′-tetrakistyranylmethyl-4,4′-diaminodiphenylmethane: TMAP
[Oxazoline compound]
Poly (styrene-co-2-isopropenyl-oxazoline) (manufactured by Nippon Shokubai Co., Ltd .: Epocross RPS-1005): PSO
1,3-bis (4,5-dihydro-2-oxazolyl) benzene: BHO
[Oxirane compounds]
Phenol-dicyclopentadiene (DCPD) resin type epoxy resin (Dainippon Ink Co., Ltd .: Epicron HP-7200HH): EPO
2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane: EES

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

<1. Synthesis of polyamic acid>
[Synthesis of polyamic acid]
Synthesis example 1
1. A 100 mL four-necked flask equipped with a thermometer, stirrer, raw material charging inlet and nitrogen gas inlet was charged with 1.676 g of 5ChCh, 1.792 g of PhPDA, and 58 g of dehydrated NMP, and stirred and dissolved in a dry nitrogen stream. . Next, 2.532 g of CBDA was added and reacted for 30 hours in a room temperature environment. When the reaction temperature rose during the reaction, the reaction temperature was kept at about 70 ° C. or lower for the reaction. 36 g of BC was added to the obtained solution to synthesize a polyamic acid solution (PA1) having a concentration of 6% by weight. The resulting PA1 had a weight average molecular weight of 37,000.

Here, the weight average molecular weight of the polyamic acid is obtained by diluting the obtained polyamic acid with a diluted solution (phosphoric acid / DMF = 0.6 / 100: weight ratio) so that the polyamic acid concentration is about 1% by weight, Using Chromatopack C-R7A (manufactured by Shimadzu Corporation), the diluted solution was measured by the GPC method using a developing agent, and determined by polystyrene conversion. In addition, the column uses GF-7HQ (made by Showa Denko KK), the column temperature is 50 ° C., and the flow rate is 0.6 mL / min.
It measured on condition of this.

Synthesis examples 2 and 3
A polyamic acid solution (PA2, PA3) was synthesized according to Synthesis Example 1 except that the composition of tetracarboxylic dianhydride, diamine and solvent was changed as shown in Table 1. The results are summarized in Table 1 including Synthesis Example 1.

Synthesis example 4
In a 100 mL four-necked flask equipped with a thermometer, a stirrer, a raw material charging charge port, and a nitrogen gas inlet port, 2.919 g of DDM, 54 g of dehydrated NMP, and 15 g of dehydrated GBL were added and stirred and dissolved under a dry nitrogen stream. Next, 1.155 g of CBDA and 1.927 g of PMDA were added, and the reaction was performed for 30 hours in a room temperature environment. When the reaction temperature rose during the reaction, the reaction temperature was kept at about 70 ° C. or lower for the reaction. 25 g of BC was added to the obtained solution to synthesize a polyamic acid solution (PA4) having a concentration of 6% by weight. The resulting PA4 had a weight average molecular weight of 45,000.

Synthesis Examples 5-10
A polyamic acid solution (PA5 to PA10) was synthesized according to Synthesis Example 4 except that the composition of tetracarboxylic dianhydride, diamine and solvent was changed as shown in Table 1. The results are summarized in Table 1, including Synthesis Example 4.

<2. Production of liquid crystal display element>
[Example 1]
The polyamic acid solution (PA1) having a concentration of 6% by weight synthesized in Synthesis Example 1 and the polyamic acid solution (PA2) having a concentration of 6% by weight synthesized in Synthesis Example 2 were mixed at a weight ratio of 1/9. To the obtained mixture, 5% by weight of TMAP, which is a thiirane compound, was added per polymer weight. Thereafter, a mixed solvent of NMP / BC = 1/1 (weight ratio) was added, and the polyamic acid was diluted to 4% by weight with respect to the whole to obtain a liquid crystal aligning agent. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

[Example 2]
The polyamic acid solution (PA1) having a concentration of 6% by weight synthesized in Synthesis Example 1 and the polyamic acid solution (PA3) having a concentration of 6% by weight synthesized in Synthesis Example 3 were mixed at a weight ratio of 1/9. PSO which is an oxazoline compound was added to the obtained mixture by 10% by weight per polymer weight. Thereafter, a mixed solvent of NMP / BC = 1/1 (weight ratio) was added, and the polyamic acid was diluted to 4% by weight with respect to the whole to obtain a liquid crystal aligning agent. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

[Comparative Example 1]
The polyamic acid solution (PA1) having a concentration of 6% by weight synthesized in Synthesis Example 1 and the polyamic acid solution (PA2) having a concentration of 6% by weight synthesized in Synthesis Example 2 were mixed at a weight ratio of 1/9. A mixed solvent of NMP / BC = 1/1 (weight ratio) was added to the obtained mixture, and the polyamic acid was diluted to 4% by weight with respect to the whole to obtain a liquid crystal aligning agent. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

[Comparative Example 2]
The polyamic acid solution (PA1) having a concentration of 6% by weight synthesized in Synthesis Example 1 and the polyamic acid solution (PA3) having a concentration of 6% by weight synthesized in Synthesis Example 3 were mixed at a weight ratio of 1/9. A mixed solvent of NMP / BC = 1/1 (weight ratio) was added to the resulting mixture, and (polyamic acid) was diluted to 4% by weight with respect to the whole to obtain a liquid crystal aligning agent. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

Manufacturing method of liquid crystal display element [Examples 1 and 2 and Comparative Examples 1 and 2]
The liquid crystal aligning agent was applied to two glass substrates with an ITO electrode with a spinner to form a film with a thickness of 70 nm. After the coating, it was heated and dried at 80 ° C. for about 5 minutes, then heat-treated at 220 ° C. for 40 minutes, and then the resulting polyimide film was rubbed to form a liquid crystal alignment film. The rubbing treatment is performed on the obtained polyimide film using a rubbing treatment device RM02-9 manufactured by Iinuma Gauge Corporation, using a rubbing cloth (hair length 1.9 mm: YA-18R rayon manufactured by Yoshikawa Chemical Co., Ltd.). It was carried out under the conditions of a push-in amount of 0.40 mm, a stage moving speed of 60 mm / sec, and a roller rotation speed of 1,000 rpm.

  The liquid crystal alignment film formed on the glass substrate was ultrasonically cleaned in ultrapure water for 5 minutes and then dried in an oven at 120 ° C. for 30 minutes.

  One glass substrate was sprayed with a 4 μm gap material, and the surface on which the liquid crystal alignment film was formed was set on the inside, and a pair of glass substrates on which the liquid crystal alignment film was formed were arranged opposite to each other so that the rubbing directions were antiparallel. Thereafter, the periphery of the liquid crystal alignment film was sealed with an epoxy curing agent to produce an anti-parallel cell with a gap of 4 μm. The liquid crystal composition I shown below was injected into the gap in the cell, and the injection port for the liquid crystal composition was sealed with a photocuring agent. Next, a heat treatment was performed at 110 ° C. for 30 minutes to manufacture a liquid crystal display element.

[Example 3]
The 6 wt% polyamic acid solution (PA4) synthesized in Synthesis Example 4 and the 6 wt% polyamic acid solution (PA5) synthesized in Synthesis Example 5 were mixed at a weight ratio of 2/8. To the resulting mixture, 10% by weight of BHO, which is an oxazoline compound, was added per polymer weight. Thereafter, a mixed solvent of NMP / BC = 1/1 (weight ratio) was added, and the polyamic acid was diluted to 4% by weight with respect to the whole to obtain a liquid crystal aligning agent. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

[Example 4]
The polyamic acid solution (PA4) having a concentration of 6% by weight synthesized in Synthesis Example 4 and the polyamic acid solution (PA6) having a concentration of 6% by weight synthesized in Synthesis Example 6 were mixed at a weight ratio of 2/8. To the resulting mixture, 10% by weight of BHO, which is an oxazoline compound, was added per polymer weight. Thereafter, a mixed solvent of NMP / BC = 1/1 (weight ratio) was added, and the polyamic acid was diluted to 4% by weight with respect to the whole to obtain a liquid crystal aligning agent. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

[Example 5]
The 6 wt% polyamic acid solution (PA4) synthesized in Synthesis Example 4 and the 6 wt% polyamic acid solution (PA7) synthesized in Synthesis Example 7 were mixed at a weight ratio of 2/8. To the resulting mixture, 10% by weight of BHO, which is an oxazoline compound, was added per polymer weight. Thereafter, a mixed solvent of NMP / BC = 1/1 (weight ratio) was added, and the polyamic acid was diluted to 4% by weight with respect to the whole to obtain a liquid crystal aligning agent. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

[Example 6]
The 6 wt% polyamic acid solution (PA4) synthesized in Synthesis Example 4 and the 6 wt% polyamic acid solution (PA7) synthesized in Synthesis Example 7 were mixed at a weight ratio of 1/9. BHO, which is an oxazoline compound, was added to the obtained mixture by 20% by weight per polymer weight. Thereafter, a mixed solvent of NMP / BC = 1/1 (weight ratio) was added, and the polyamic acid was diluted to 4% by weight with respect to the whole to obtain a liquid crystal aligning agent. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

[Example 7]
The 6 wt% polyamic acid solution (PA4) synthesized in Synthesis Example 4 and the 6 wt% polyamic acid solution (PA7) synthesized in Synthesis Example 7 were mixed at a weight ratio of 2/8. PSO which is an oxazoline compound was added to the obtained mixture by 10% by weight per polymer weight. Thereafter, a mixed solvent of NMP / BC = 1/1 (weight ratio) was added, and the polyamic acid was diluted to 4% by weight with respect to the whole to obtain a liquid crystal aligning agent. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

[Example 8]
To the polyamic acid solution (PA8) having a concentration of 6% by weight synthesized in Synthesis Example 8, 10% by weight of BHO as an oxazoline compound was added per polymer weight. Thereafter, a mixed solvent of NMP / BC = 1/1 (weight ratio) was added, and the polyamic acid was diluted to 4% by weight with respect to the whole to obtain a liquid crystal aligning agent. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

[Example 9]
To the polyamic acid solution (PA9) having a concentration of 6% by weight synthesized in Synthesis Example 9, 20% by weight of BHO as an oxazoline compound was added per polymer weight. Thereafter, a mixed solvent of NMP / BC = 1/1 (weight ratio) was added, and the polyamic acid was diluted to 4% by weight with respect to the whole to obtain a liquid crystal aligning agent. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

[Example 10]
To the polyamic acid solution (PA10) having a concentration of 6% by weight synthesized in Synthesis Example 10, 10% by weight of BHO as an oxazoline compound was added per polymer weight. Thereafter, a mixed solvent of NMP / BC = 1/1 (weight ratio) was added, and the polyamic acid was diluted to 4% by weight with respect to the whole to obtain a liquid crystal aligning agent. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

[Example 11]
To the polyamic acid solution (PA9) having a concentration of 6% by weight synthesized in Synthesis Example 9, 10% by weight of PSO as an oxazoline compound was added per polymer weight. Thereafter, a mixed solvent of NMP / BC = 1/1 (weight ratio) was added, and the polyamic acid was diluted to 4% by weight with respect to the whole to obtain a liquid crystal aligning agent. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

[Example 12]
The 6 wt% polyamic acid solution (PA4) synthesized in Synthesis Example 4 and the 6 wt% polyamic acid solution (PA5) synthesized in Synthesis Example 5 were mixed at a weight ratio of 2/8. BHO, which is an oxazoline compound, was added to the obtained mixture by 10% by weight per polymer weight, and EPO, which was an oxirane compound, was added by 10% by weight per polymer weight. Thereafter, a mixed solvent of NMP / BC = 1/1 (weight ratio) was added, and the polyamic acid was diluted to 4% by weight with respect to the whole to obtain a liquid crystal aligning agent. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

[Example 13]
The 6 wt% polyamic acid solution (PA4) synthesized in Synthesis Example 4 and the 6 wt% polyamic acid solution (PA5) synthesized in Synthesis Example 5 were mixed at a weight ratio of 2/8. To the resulting mixture, 10% by weight of BHO as an oxazoline compound was added per polymer weight, and 10% by weight of EES as an oxirane compound was added per polymer weight. Thereafter, a mixed solvent of NMP / BC = 1/1 (weight ratio) was added, and the polyamic acid was diluted to 4% by weight with respect to the whole to obtain a liquid crystal aligning agent. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

[Comparative Example 3]
The 6 wt% polyamic acid solution (PA4) synthesized in Synthesis Example 4 and the 6 wt% polyamic acid solution (PA5) synthesized in Synthesis Example 5 were mixed at a weight ratio of 2/8. A mixed solvent of NMP / BC = 1/1 (weight ratio) was added to the obtained mixture, and the polyamic acid was diluted to 4% by weight with respect to the whole to obtain a liquid crystal aligning agent. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

[Comparative Example 4]
The 6 wt% polyamic acid solution (PA4) synthesized in Synthesis Example 4 and the 6 wt% polyamic acid solution (PA7) synthesized in Synthesis Example 7 were mixed at a weight ratio of 2/8. A mixed solvent of NMP / BC = 1/1 (weight ratio) was added to the obtained mixture, and the polyamic acid was diluted to 4% by weight with respect to the whole to obtain a liquid crystal aligning agent. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

[Comparative Example 5]
The polyamic acid solution (PA9) having a concentration of 6% by weight synthesized in Synthesis Example 9 was added with a mixed solvent of NMP / BC = 1/1 (weight ratio), and the polyamic acid was diluted to 4% by weight with respect to the whole to obtain liquid crystal. An aligning agent was used. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

[Comparative Example 6]
A 6 wt% polyamic acid solution (PA10) synthesized in Synthesis Example 10 was added with a mixed solvent of NMP / BC = 1/1 (weight ratio), and the polyamic acid was diluted to 4 wt% based on the whole to obtain a liquid crystal. An aligning agent was used. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

Manufacturing method of liquid crystal display element [Examples 3 to 13 and Comparative Examples 3 to 6]
The liquid crystal aligning agent was applied to two glass substrates with an ITO electrode with a spinner to form a film with a thickness of 70 nm. After coating, the film was heated and dried at 80 ° C. for about 5 minutes, then heat-treated at 220 ° C. for 20 minutes, and then the resulting polyimide film was rubbed to form a liquid crystal alignment film. The rubbing treatment is performed on the obtained polyimide film using a rubbing treatment device RM02-9 manufactured by Iinuma Gauge Corporation, using a rubbing cloth (hair length 1.9 mm: YA-18R rayon manufactured by Yoshikawa Chemical Co., Ltd.). It was carried out under the conditions of a push-in amount of 0.40 mm, a stage moving speed of 60 mm / sec, and a roller rotation speed of 1,000 rpm.

  The liquid crystal alignment film formed on the glass substrate was ultrasonically cleaned in ultrapure water for 5 minutes and then dried in an oven at 120 ° C. for 30 minutes.

  A pair of glass substrates on which a liquid crystal alignment film was formed were placed opposite to each other so that the rubbing direction was antiparallel, with a surface on which the liquid crystal alignment film was formed on the inside, with a 7 μm gap material dispersed on one glass substrate. Thereafter, the periphery of the liquid crystal alignment film was sealed with an epoxy curing agent to produce an anti-parallel cell with a gap of 7 μm. A liquid crystal composition II shown below was injected into the gap in the cell, and an injection port for the liquid crystal composition was sealed with a photocuring agent. Next, a heat treatment was performed at 110 ° C. for 30 minutes to manufacture a liquid crystal display element.

<3. Evaluation of electrical characteristics>
[Test Examples 1 to 19]
About the liquid crystal display element produced in Examples 1-13 and Comparative Examples 1-6, the measurement of the voltage holding rate and the long-term reliability were performed as follows.

1) Measurement of voltage holding ratio The voltage holding ratio was measured using a liquid crystal property evaluation apparatus 6254 type manufactured by Toyo Technica. The measurement conditions were a gate width of 60 μs, a frequency of 0.3 Hz, a wave height of ± 5 V, and a measurement temperature of 60 ° C. It can be said that the larger this value, the better the electrical characteristics. The results are shown in Tables 2 and 3.

2-1) Measurement of long-term reliability [Test Examples 1 to 4]
About the produced liquid crystal display element, the voltage retention rate was calculated | required with time and the retention | holding characteristic was evaluated. As a test method for holding characteristics, a liquid crystal display element was left in an atmosphere at a temperature of 100 ° C. for 100 hours, taken out during the course of time, and measured for voltage holding ratio. It can be said that the smaller the decrease in the voltage holding ratio (for example, the longer the standing time is 100 hours under the above conditions and the lowering ratio of the voltage holding ratio is less than 1%), the better the long-term reliability. The results are shown in Table 2. The decrease rate is obtained from the following equation.
Decrease rate (%) = (initial voltage holding rate−final voltage holding rate) / (initial voltage holding rate) × 100

2-2) Measurement of long-term reliability [Test Examples 5 to 19]
About the produced liquid crystal display element, the voltage retention rate was calculated | required with time and the retention | holding characteristic was evaluated. As a test method for holding characteristics, the liquid crystal display element was left in an atmosphere at a temperature of 60 ° C. for 500 hours, and the voltage holding ratio was measured by taking it out over time. It can be said that the smaller the decrease in the voltage holding ratio is, the better the long-term reliability is (for example, when the standing time is 500 hours or more and the decreasing ratio of the voltage holding ratio is less than 2% under the above conditions). The results are shown in Table 3.

  As shown in Tables 2 and 3, in the case of a liquid crystal display element using a liquid crystal alignment film in which the above described compounds were mixed, deterioration of storage characteristics was remarkably suppressed. This is considered to be a result of the thiirane compound and the oxazoline compound each having some action such as a reaction on the polyamic acid. Further, considering the reactivity in the heterocyclic structure and the like, the same effect as the thiirane compound and the oxazoline compound is expected for the oxetane compound and the aziridine compound.

  Furthermore, in the liquid crystal aligning agent, when the oxirane compound was used in combination with the above described compound, the deterioration of the storage characteristics of the obtained liquid crystal display element was more remarkably suppressed than when the above described compound was used alone. .

As described above, the liquid crystal aligning agent containing the polyamic acid and the above-described compound in the present invention has a high voltage holding ratio and remarkably suppresses deterioration of storage characteristics when used as a liquid crystal alignment film of a liquid crystal display element. can do.

Claims (22)

Oxetane, thiirane, and one or more heterocyclic compounds having one or more hetero ring structure selected from the group consisting 及 beauty oxazolines, and one or more polymers selected from the polyamic acid and derivatives thereof A liquid crystal aligning agent comprising 0.1 to 50% by weight of the heterocyclic compound based on the polymer ;
The polyamic acid and derivatives thereof are reaction products obtained by reacting tetracarboxylic dianhydride as an acid component and diamine as an amine component,
The liquid crystal aligning agent characterized by the tetracarboxylic dianhydride as said acid component being 1 or more types of the tetracarboxylic dianhydride represented by following Structural formula (1)-(67) .

  The liquid crystal aligning agent according to claim 1, wherein the heterocyclic compound is a compound having two or more of the heterocyclic structures.   The liquid crystal aligning agent according to claim 1, wherein the heterocyclic compound is a polymer having the heterocyclic structure in a side chain.   The liquid crystal aligning agent according to claim 3, wherein the polymer is a copolymer. The tetracarboxylic dianhydride as the acid component includes an A component and a B component, and an aromatic tetracarboxylic dianhydride is used as the A component. The aromatic tetracarboxylic dianhydride has the following structural formula ( It is a compound chosen from the group comprised from 1), (2), (5)-(7), and (14), The liquid crystal aligning agent as described in any one of Claims 1-4 characterized by the above-mentioned. .

6. The liquid crystal aligning agent according to claim 5, wherein the aromatic tetracarboxylic dianhydride is a compound of the structural formula (1). The liquid crystal aligning agent according to claim 5 or 6, characterized by using one or both of the aliphatic tetracarboxylic dianhydrides and alicyclic tetracarboxylic acid dianhydride as a pre-Symbol B component. The aliphatic tetracarboxylic dianhydride and the alicyclic tetracarboxylic dianhydride are represented by the following structural formulas (19), (23), (25), (35) to (37), (39), (44 And a liquid crystal aligning agent according to claim 7 , wherein the liquid crystal aligning agent is a compound selected from the group consisting of (49) and (49).

The liquid crystal aligning agent according to claim 8, wherein the alicyclic tetracarboxylic dianhydride is a compound selected from the group consisting of the structural formulas (19), (23), and (49). The amine component includes an A component and a B component, and a diamine represented by a general formula selected from the group consisting of the following general formulas (I) to (VII) is used as the A component of the amine. the liquid crystal alignment agent according to any one of claims 1-9.

(In the general formula (I), A ¹ represents — (CH ₂ ) _m —. Here, m represents an integer of 1 to 12. In the general formulas (III), (V), and (VII), A ¹ is independently a single bond, —O—, —S—, —S—S—, —SO ₂ —, —CO—, —CONH—, —NHCO—, —C (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ —, — (CH ₂ ) _m —, —O— (CH ₂ ) _m —O—, or —S— (CH ₂ ) _m —S—, where m is 1 to And represents an integer of 12. In formula (VI), A ² independently represents a single bond, —O—, —S—, —CO—, —C (CH ₃ ) ₂ —, —C (CF _{3). 2} ) represents an alkylene having 1 to 6 carbon atoms, and hydrogen bonded to a cyclohexane ring or a benzene ring in the general formulas (II) to (VII) is independently -F, -CH ₃ ,- OH, -COOH, -SO ₃ H -PO ₃ H _2, may be replaced with benzyl or 4-hydroxybenzyl.) The diamine of component A is represented by the following structural formulas (IV-1), (IV-2), (IV-15), (IV-16), (V-1) to (V-12), (V-33). The liquid crystal aligning agent according to claim 10 , which is a compound selected from the group consisting of: (VII-1) and (VII-2).

Following general formula as component B of the amine (VIII) and (IX) ~ according to claim 10 or 11, characterized by using a diamine represented by the general formula selected from the group consisting of (XII) LCD Alignment agent.

(In the general formula (VIII), R ¹ is a single bond, —O—, —CO—, —COO—, —OCO—, —CONH—, —CH ₂ O—, —CF ₂ O— or (CH ₂ ). _e- , wherein e is an integer of 1 to 6; R ² is a group having a steroid skeleton, a group represented by the general formula (XIII), alkyl having 1 to 30 carbons, or phenyl; Any of —CH ₂ — may be independently replaced by —O— (but not consecutively), —CH═CH— or —C≡C—, And the hydrogen of this phenyl may be independently replaced by fluorine, methyl, methoxy, fluoromethoxy, difluoromethoxy or trifluoromethoxy:
In the general formula (IX), R ³ is independently hydrogen or methyl; R ⁴ is hydrogen or alkyl having 1 to 30 carbon atoms; R ⁵ is independently a single bond, —CO— or —CH _2. -Is:
In the general formula (X), R ³ is independently hydrogen or methyl; R ⁴ is hydrogen or alkyl having 1 to 30 carbon atoms; R ⁵ is independently a single bond, —CO— or —CH _2. And R ⁶ and R ⁷ are independently hydrogen, alkyl having 1 to 30 carbons, or phenyl:
In the general formula (XI), R ⁸ is hydrogen or alkyl having 1 to 30 carbon atoms, and any —CH ₂ — of the alkyl is independently —O— (but not consecutively), —CH═ May be replaced by CH— or —C≡C—; R ⁹ is independently —O— or alkylene having 1 to 6 carbons; ring A is 1,4-phenylene or 1,4-cyclohexylene A is 0 or 1; b is 0, 1 or 2; and c is independently 0 or 1:
In General Formula (XII), R ¹⁰ is alkyl having 3 to 30 carbons or fluorinated alkyl having 3 to 30 carbons; R ¹¹ is hydrogen, alkyl having 1 to 30 carbons, or 1 to 30 carbons. R ¹² is independently —O— or alkylene having 1 to 6 carbons; and d is independently 0 or 1. )

(In the general formula (XIII), R ¹³ , R ¹⁴ and R ¹⁵ are independently a single bond, —O—, —COO—, —OCO—, —CONH—, alkylene having 1 to 4 carbon atoms, 1 carbon atom, ˜3 oxyalkylene, or C 1-3 alkyleneoxy (but oxygen is not continuously bonded); R ¹⁶ and R ¹⁷ are independently hydrogen, fluorine or methyl; R ¹⁸ is hydrogen, Fluorine, chlorine, cyano, alkyl having 1 to 30 carbon atoms, alkoxy having 1 to 30 carbon atoms, alkoxyalkyl having 2 to 30 carbon atoms, fluoromethyl, difluoromethyl, trifluoromethyl, fluoromethoxy, difluoromethoxy or trifluoromethoxy In these alkyl, alkoxy and alkoxyalkyl, any —CH ₂ — is represented by difluoromethylene or general formula (XIV). Ring B and ring C are independently 1,4-phenylene or 1,4-cyclohexylene; f, g and h are independently an integer from 0 to 4; i, j and k are each independently an integer of 0 to 3, and their sum is 1 or more; l and m are independently 1 or 2.)

(In the general formula (XIV), R ¹⁹ , R ²⁰ , R ²¹ and R ²² are independently alkyl having 1 to 10 carbons or phenyl, and n is an integer of 1 to 100.) The diamine of component B is represented by the following general formulas (VIII-2), (VIII-4), (VIII-5), (VIII-6), (XI-1), (XI-2) and (XI-6). 13. A liquid crystal aligning agent according to claim 12, which is a diamine represented by a general formula selected from the group consisting of:

(In the general formula, R ²³ independently represents an alkyl group having 3 to 30 carbon atoms or an alkoxy group having 3 to 30 carbon atoms, R ²⁹ represents hydrogen or an alkyl group having 1 to 30 carbon atoms, R ³⁰ Represents hydrogen or an alkyl group having 1 to 20 carbon atoms.) The liquid crystal aligning agent according to any one of claims 1 to 13 , comprising two or more kinds of the polymers. The liquid crystal aligning agent according to any one of claims 1 to 14 , further comprising an oxirane compound. A liquid crystal aligning agent comprising a heterocyclic compound having one or more heterocyclic structures of thiirane and oxazoline, and a polyamic acid or a derivative thereof,
Containing 1 to 40% by weight of the heterocyclic compound with respect to the polyamic acid or a derivative thereof;
The polyamic acid or derivative thereof is a reaction product obtained by reacting tetracarboxylic dianhydride as an acid component and diamine as an amine component,
The tetracarboxylic dianhydride is one or more compounds selected from the group consisting of the following structural formulas (1), (2), (5) to (7) and (14) as the A component of the acid. And a compound selected from the group consisting of the following structural formulas (19), (23), (25), (35) to (37), (39), (44) and (49) as the B component of the acid One or more of one or both of
The diamine has the following structural formulas (IV-1), (IV-2), (IV-15), (IV-16), (V-1) to (V-12), (V) as the A component of the amine. -33), one or more compounds selected from the group consisting of (VII-1) and (VII-2), and the following general formulas (VIII-2) and (VIII-4) as the B component of the amine One or two or more compounds represented by the general formula selected from the group consisting of: (VIII-5), (VIII-6), (XI-1), (XI-2) and (XI-6) A liquid crystal aligning agent characterized by being one or both of the above.

(In the general formula, R ²³ independently represents an alkyl group having 3 to 30 carbon atoms or an alkoxy group having 3 to 30 carbon atoms, R ²⁹ represents hydrogen or an alkyl group having 1 to 30 carbon atoms, R ³⁰ Represents hydrogen or an alkyl group having 1 to 20 carbon atoms.) The tetracarboxylic dianhydride comprises the compound of the structural formula (1) as the A component of the acid and the structural formulas (19), (23) and (49) as the B component of the acid. Any one or both of the compounds selected from
The diamine is one or more compounds selected from the group consisting of the structural formulas (IV-16), (V-1), (V-7) and (VII-2) as the A component of the amine. , And B component of the amine, or both,
The heterocyclic compound includes N, N, N ′, N ′,-tetrakistyranylmethyl-4,4′-diaminodiphenylethane, poly (styrene-co-2-isopropenyloxazoline), and 1,3-bis. The liquid crystal aligning agent according to claim 16 , wherein the liquid crystal aligning agent is one or more compounds selected from the group consisting of (4,5-dihydro-2-oxazolyl) benzene. The B component of the amine is a general formula selected from the group consisting of the general formulas (VIII-2), (VIII-5), (XI-1), (XI-2) and (XI-6). The liquid crystal aligning agent according to claim 17 , which is one or more of the represented compounds. The liquid crystal aligning agent according to any one of claims 16 to 18 , further comprising an oxirane compound. The liquid crystal aligning agent according to claim 19 , wherein the oxirane compound is one or both of a phenol-dicyclopentadiene resin type epoxy resin and 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane. . 21. A liquid crystal alignment film formed by firing the liquid crystal aligning agent according to any one of claims 1 to 20 in a film state. A pair of substrates arranged opposite to each other, electrodes formed on one or both of the opposed surfaces of each of the pair of substrates, and liquid crystal alignment formed on the opposed surfaces of each of the pair of substrates In a liquid crystal display element having a film and a liquid crystal layer formed between the pair of substrates,
The liquid crystal display element according to claim 21 , wherein the liquid crystal alignment film is the liquid crystal alignment film according to claim 21 .