JP5077583B2 - Liquid crystal aligning agent and liquid crystal display element - Google Patents

Description

  The present invention relates to a liquid crystal aligning agent and a liquid crystal display element.

Currently, as a liquid crystal display element, a liquid crystal alignment film made of polyamic acid, polyimide, or the like is formed on the surface of a substrate on which a transparent conductive film is provided to form a liquid crystal display element substrate. A nematic liquid crystal layer having a positive dielectric anisotropy is formed in a cell having a sandwich structure so that the major axis of the liquid crystal molecules is continuously twisted by 90 ° from one substrate to the other. A TN type liquid crystal display element having a so-called TN type (Twisted Nematic) liquid crystal cell is known. Further, TN type than the liquid crystal display device capable of realizing a high contrast ratio STN (Super Twisted Nematic) type liquid crystal display device and the viewing angle dependence less IPS (In-Plane Switching) type liquid crystal display device, VA (Vertical A li (gnment) type liquid crystal display element, and an optical compensation bend (OCB) type liquid crystal display element that is less dependent on viewing angle and excellent in high-speed response of an image screen has been developed (see Patent Documents 1 to 3 and Non-Patent Document 1). .
As materials for the liquid crystal alignment film in these liquid crystal display elements, organic films such as polyimide, polyamide and polyester have been conventionally known. In particular, polyimide has heat resistance, affinity with liquid crystal, mechanical strength, electrical characteristics. And is used in many liquid crystal display elements (see Patent Document 4).

In general, in order to manufacture a liquid crystal display element, a step of injecting and filling liquid crystal into a gap (cell gap) between two substrates on which a liquid crystal alignment film is formed is necessary. For filling and filling the liquid crystal, a vacuum filling method in which liquid crystal is filled between substrates of a liquid crystal display element by utilizing a pressure difference between atmospheric pressure and vacuum is generally performed, but a substrate of only 3 to 6 μm is used. Since a considerable amount of time is required for the liquid crystal to flow through the gaps between them, a long time is required for the manufacturing process, and it has been desired to shorten the manufacturing process particularly for large panels.
A liquid crystal dropping method (ODF method) has been developed as a new liquid crystal filling method that solves the problems in the vacuum injection method described above. This is because a required amount of liquid crystal is dropped on a substrate on which a liquid crystal alignment film is formed, and bonded to the other substrate in a vacuum, and then a sealant for sealing the liquid crystal is UV-cured, so that the entire surface of the panel is covered. This is a technique for filling liquid crystal (see Patent Document 5). This technique is expected as a technique that can significantly reduce the time required for the liquid crystal filling process. However, when a substrate having a conventionally known liquid crystal alignment film is applied to the ODF process, the wetting and spreading speed of the liquid crystal molecules on the liquid crystal alignment film is not sufficiently high, and the time for filling the liquid crystal is still insufficient. There is a problem that it is.

Further, in recent years, due to a tendency to reduce the thickness and display area of liquid crystal display elements, a technique for narrowing a region where pixels are not formed on the outer edge of a substrate (generally called “frame region” among those skilled in the art). Application of so-called narrowing frame technology is being studied. When the narrow frame technology is applied, it is necessary to reduce the application area of the sealing agent that bonds the two glass substrates, and thus the adhesive strength between the substrates tends to decrease. Furthermore, recently, for the purpose of further narrowing the frame, a technique for applying and adhering a sealing agent onto a liquid crystal alignment film formed on a glass substrate has been studied. In this case, the adhesion strength of the liquid crystal alignment film to the substrate and the sealant becomes a big problem. In particular, it is generally known that the adhesive strength at the interface between the organic film and the sealing agent tends to be weaker than the adhesive strength at the interface between the glass substrate and the sealing agent. In order to achieve this, it is essential to improve the adhesive strength (adhesion) at the liquid crystal alignment film-sealant interface.
However, as a study on the adhesion of the liquid crystal alignment film, there are many studies on the adhesion to the glass substrate or the transparent conductive film, but there are few examples of examining the adhesion to the sealing agent, and the adhesion to the sealing agent and the liquid crystal alignment film. As a result, there are no known reports on studying compatibility with various performances originally required.

JP-A-4-153622 JP 60-107020 A Japanese Patent Laid-Open No. 11-258605 Japanese Patent Laid-Open No. 62-165628 JP 2001-174829 A JP-A-6-222366 JP-A-6-281937 JP-A-5-107544

SID '94 Digest p. 927 (1994)

An object of the present invention is to provide a liquid crystal aligning agent having a property that liquid crystals are rapidly wetted and spread when a liquid crystal dropping method (ODF) is applied in the production of a liquid crystal display element.
Another object of the present invention is to provide a liquid crystal aligning agent that provides various properties required as a liquid crystal aligning film and that provides a liquid crystal aligning film that is particularly excellent in adhesion to a sealant.
Still another object of the present invention is to provide a liquid crystal display device which is excellent in electrical characteristics and exhibits a high degree of display quality.
Still other objects and advantages of the present invention will become apparent from the following description.

According to the present invention, the above objects and advantages of the present invention are as follows.
(A) at least one polymer selected from the group consisting of polyamic acid and imidized polymer thereof, and (b) a liquid crystal containing a compound having two epoxy groups and one or more fluorine atoms in the molecule Achieved by an alignment agent, and secondly,
This is achieved by a liquid crystal display device comprising a liquid crystal alignment film formed from the liquid crystal alignment agent.

When the liquid crystal alignment film is formed from the liquid crystal aligning agent of the present invention, it is possible to sufficiently shorten the time for the liquid crystal filling step by the ODF method. Moreover, the liquid crystal aligning film formed from the liquid crystal aligning agent of the present invention has various performances required as a liquid crystal aligning film at a high level and is particularly excellent in adhesion to a sealant. Can be suitably used for various liquid crystal display elements such as TN type, STN type, VA type, IPS type, OCB type, ferroelectricity, and antiferroelectricity.
The liquid crystal display element of the present invention is excellent in electrical characteristics and exhibits high display quality. Such a liquid crystal display element of the present invention can be used effectively in various devices, for example, it can be suitably used in display devices such as desk calculators, wrist watches, table clocks, counting display boards, word processors, personal computers, and liquid crystal televisions. it can.

The liquid crystal aligning agent of the present invention is
(A) at least one polymer selected from the group consisting of polyamic acid and imidized polymer thereof, and (b) a compound having two epoxy groups and one or more fluorine atoms in the molecule (hereinafter referred to as “ It is called an “epoxy compound having a fluorine atom”.)
Containing.
Hereinafter, each component which the liquid crystal aligning agent of this invention contains is demonstrated.
(A) Polymer The (a) polymer contained in the liquid crystal aligning agent of the present invention is at least one selected from the group consisting of a polyamic acid and an imidized polymer thereof.
<Polyamic acid>
The polyamic acid can be synthesized by reacting tetracarboxylic dianhydride with diamine.

[Tetracarboxylic dianhydride]
Examples of the tetracarboxylic dianhydride used for synthesizing the polyamic acid used in the present invention include butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1 , 2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dichloro-1 , 2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4- Cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3 ′, 4,4′-dicyclohexyltetracarboxylic dianhydride, 2,3,5 Tricarboxycyclopentylacetic acid dianhydride, 3,5,6-tricarboxynorbornane-2-acetic acid dianhydride, 2,3,4,5-tetrahydrofurantetracarboxylic dianhydride, 1,3,3a, 4,5 , 9b-Hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b- Hexahydro-5-methyl-5 (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b- Hexahydro-5-ethyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b -Hexahydro-7-methyl-5- (Tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-7-ethyl-5 -(Tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl- 5- (Tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-ethyl -5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5 8-Dimethyl-5- (tetrahydro-2,5-dioxo-3-furani ) -Naphtho [1,2-c] -furan-1,3-dione, 5- (2,5-dioxotetrahydrofuranyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, bicyclo [2.2.2] -Oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 3-oxabicyclo [3.2.1] octane-2,4-dione-6 Spiro-3 ′-(tetrahydrofuran-2 ′, 5′-dione), 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride, 3,5,6-tricarboxy-2-carboxynorbornane-2: 3,5: 6-dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] undecane-3, 5,8,10-tetraone, the following formula (TI) and (T-II)

(In the formulas (T-I) and (T-II), R ¹ and R ³ each represent a divalent organic group having an aromatic ring, and R ² and R ⁴ each represent a hydrogen atom or an alkyl group. And a plurality of R ² and R ⁴ may be the same or different.)
An aliphatic or alicyclic tetracarboxylic dianhydride such as a compound represented by each of the following:
Pyromellitic dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenylsulfone tetracarboxylic dianhydride, 1,4,5, 8-naphthalene tetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenyl ether tetracarboxylic dianhydride, 3,3 ′, 4,4′-dimethyldiphenylsilanetetracarboxylic dianhydride, 3,3 ′, 4,4′-tetraphenylsilanetetracarboxylic dianhydride, 1,2,3,4-furantetracarboxylic dianhydride 4,4′-bis (3,4-dicarboxyphenoxy) diphenyl sulfide dianhydride, 4,4′-bis (3,4-dicarboxyphenoxy) diphenylsulfone dianhydride, 4,4′-bis ( 3,4-dicar Boxyphenoxy) diphenylpropane dianhydride, 3,3 ′, 4,4′-perfluoroisopropylidene diphthalic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2 , 2 ′, 3,3′-biphenyltetracarboxylic dianhydride, bis (phthalic acid) phenylphosphine oxide dianhydride, p-phenylene-bis (triphenylphthalic acid) dianhydride, m-phenylene-bis ( Triphenylphthalic acid) dianhydride, bis (triphenylphthalic acid) -4,4′-diphenyl ether dianhydride, bis (triphenylphthalic acid) -4,4′-diphenylmethane dianhydride, ethylene glycol-bis ( Anhydrotrimellitate), propylene glycol-bis (anhydrotrimellitate), 1,4-butanediol-bis (anhydrotrimellitate) Retate), 1,6-hexanediol-bis (anhydrotrimellitate), 1,8-octanediol-bis (anhydrotrimellitate), 2,2-bis (4-hydroxyphenyl) propane-bis ( Anhydrotrimellitate), the following formulas (T-1) to (T-4)

An aromatic tetracarboxylic dianhydride such as a compound represented by each of the above can be exemplified. These may be used alone or in combination of two or more.
Among the above, tetracarboxylic dianhydride used for synthesizing the polyamic acid used in the present invention is butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentyl acetate Anhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, , 3,3a, 4,5,9b-Hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, , 3, 3 , 4,5,9b-Hexahydro-5,8-dimethyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, bicyclo [2 2.2.2] -Oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 3-oxabicyclo [3.2.1] octane-2,4-dione-6-spiro- 3 ′-(tetrahydrofuran-2 ′, 5′-dione), 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride, 3, 5,6-tricarboxy-2-carboxynorbornane-2: 3,5: 6-dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] undecane-3,5 8,10-tetraone, pyromellitic dianhydride, 3,3 ′ 4,4′-benzophenone tetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenylsulfone tetracarboxylic dianhydride, 2,2 ′, 3,3′-biphenyltetracarboxylic dianhydride, 1,4,5,8-Naphthalenetetracarboxylic dianhydride, among the compounds represented by the above formula (TI), the following formulas (T-5) to (T-7)

And the following formula (T-8) among the compounds represented by formula (T-II):

In at least one selected from the group consisting of compounds represented by (hereinafter, "specific tetracarboxylic dianhydride 1" hereinafter.) By are use a tetracarboxylic acid dianhydride containing, liquid crystals formed alignment film Ru can express good liquid crystal orientation. Examples of the specific tetracarboxylic dianhydride include 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 1,3,3a, 4,5. , 9b-Hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro -8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 3-oxabicyclo [3.2.1] octane- 2,4-dione-6-spiro-3 ′-(tetrahydrofuran-2 ′, 5′-dione), 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1 , 2-Dicarboxylic anhydride , 3,5,6-tricarboxy-2-carboxymethyl norbornane -2: 3,5: 6-dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^{2, 6]} undecane -3 , 5,8,10-tetraone, pyromellitic dianhydride and at least one selected from the group consisting of the compounds represented by the above formula (T-5) is more preferable, and 2,3,5-trione is more preferable. Carboxycyclopentyl acetic acid dianhydride is preferred.
The tetracarboxylic dianhydride used for synthesizing the polyamic acid used in the present invention is 10 mol% or more of the specific tetracarboxylic dianhydride 1 as described above with respect to the total tetracarboxylic dianhydride. der those containing is, 20 mol% or more, including those in which it is favorable preferred, and particularly preferably those containing more than 50 mol%.

[Diamine]
Examples of the diamine used for synthesizing the polyamic acid used in the present invention include aromatic diamine, aliphatic diamine, alicyclic diamine, and diaminoorganosiloxane.
Examples of the aromatic diamine include the following formulas (DI) to (D-IV).

(R ⁵ in the formula (DI) is an alkyl group having 6 to 30 carbon atoms, or a monovalent having a ring structure containing a nitrogen atom selected from the group consisting of pyridine, pyrimidine, triazine, piperidine and piperazine. X ¹ is a single bond, —O— ^* , —COO— ^* , —OCO— ^* , —NHCO— ^* , —CONH— ^* or —CO— ^* (provided with “*”). A bond is bonded to R ⁵ ), R ⁶ is an alkyl group having 1 to 4 carbon atoms, a1 is an integer of 0 to 3,
R ^{7 in} formula (D-II) is a divalent organic group having a ring structure containing a nitrogen atom selected from pyridine, pyrimidine, triazine, piperidine and piperazine, and X ² is —O— ^* , -COO- ^*, -OCO- ^*, -NHCO- ^*, -CONH- ^* or -CO- ^* (However, bond marked with "*" is bonded to ^{R 7.)} a and, X presence of a plurality of ² may be the same or different, R ⁸ is an alkyl group having 1 to 4 carbon atoms, a2 is an integer of 0 to 4 respectively.
R ⁹ in the formula (D-III) is a monovalent organic group having a steroid skeleton, and X ³ is a single bond, —O— ^* , —COO— ^* , —OCO— ^* , —NHCO— ^* , — CONH- ^* or -CO- ^* (wherein "*" a bond marked is bonded to ^{R 9.) is, R 10} is an alkyl group having 1 to 4 carbon atoms, a3 is 0-3 An integer,
R ¹¹ in the formula (D-IV) is a divalent organic group having a steroid skeleton, and X ⁴ is —O— ^* , —COO— ^* , —OCO— ^* , —NHCO— ^* , — CONH- ^* or -CO- ^* (However, bond marked with "*" is. to bind to ^{R 11) is, R 12} are each an alkyl group having 1 to 4 carbon atoms, a4 is Each is an integer from 0 to 4. )
The compound represented by each of these, the aromatic diamine which has a fluorine atom, and another aromatic diamine can be mentioned.
R ⁶ , R ⁸ , R ¹⁰ and R ^{12 in the} above formulas (DI) to (D-IV) are each preferably a methyl group, and a1, a2, a3 and a4 are each 0 Or it is preferable that it is 1, and it is more preferable that it is 0.
Examples of the compound represented by the above formula (DI) include dodecanoxy-2,4-diaminobenzene, pentadecanoxy-2,4-diaminobenzene, hexadecanoxy-2,4-diaminobenzene, octadecanoxy-2,4-diamino. Benzene, dodecanoxy-2,5-diaminobenzene, pentadecanoxy-2,5-diaminobenzene, hexadecanoxy-2,5-diaminobenzene, octadecanoxy-2,5-diaminobenzene, the following formula (D-1)

A compound represented by:
Examples of the compound represented by the formula (D-II) include the following formula (D-2)

And the like can be mentioned respectively.
Examples of the monovalent organic group having a steroid skeleton of R ^{9 in} the above formula (D-III) include a 3-cholestanyl group, a 3-cholestenyl group, a 3-lanostanyl group, and a lanostenyl group. Specific examples of the compound represented by the formula (D-III) include, for example, the following formulas (D-3) to (D-8):

And the like, and the like.
Examples of the divalent organic group having a steroid skeleton of R ^{11 in} the above formula (D-IV) include cholestane-3,6-diyl group, cholesterol-3,6-diyl group, cholestane-3,3-bis ( 1,4-phenylene) group and the like. Specific examples of the compound represented by the above formula (D-IV) include, for example, the following formulas (D-9) to (D-11):

And the like, and the like.
Examples of the aromatic diamine having a fluorine atom include the following formula (D-V):

(In the formula (D-V), R ¹³ is a monovalent organic group having a group selected from the group consisting of a trifluoromethylphenyl group, a trifluoromethoxyphenyl group and a fluorophenyl group, and X ⁵ is —O—. ^* , —COO— ^* , —OCO— ^* , —NHCO— ^* , —CONH— ^*, or —CO— ^* (where a bond marked with “*” binds to R ¹³ ), and R ^14. Is an alkyl group having 1 to 4 carbon atoms, and a5 is an integer of 0 to 3.)
2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 2,2′-ditrifluoromethyl- 4,4′-diaminobiphenyl, 3,3′-ditrifluoromethyl-4,4′-diaminobiphenyl, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2′- Bis [4- (4-amino-2-trifluoromethylphenoxy) phenyl] hexafluoropropane, 4,4′-diamino-2,2′-bis (trifluoromethyl) biphenyl, 4,4′-bis [( 4-amino-2-trifluoromethyl) phenoxy] -octafluorobiphenyl and the like.
R ¹⁴ in the above formula (D-V) is preferably a methyl group, and a5 is preferably 0 or 1, more preferably 0.
Specific examples of the compound represented by the above formula (D-V) include, for example, the following formulas (D-12) to (D-14):

And the like, and the like. Of these, preferred aromatic diamines having a fluorine atom include compounds represented by the above formula (D-V), 2,2′-ditrifluoromethyl-4,4′-diaminobiphenyl, 2,2 -Bis [4- (4-aminophenoxy) phenyl] hexafluoropropane and 2,2-bis (4-aminophenyl) hexafluoropropane can be mentioned, and particularly preferable aromatic diamines having fluorine atoms are Compounds represented by each of (D-12) to (D-14) and 2,2′-ditrifluoromethyl-4,4′-diaminobiphenyl, 2,2-bis [4- (4-aminophenoxy) Phenyl] hexafluoropropane and 2,2-bis (4-aminophenyl) hexafluoropropane can be exemplified.
Examples of the other aromatic diamines include p-phenylenediamine, m-phenylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylethane, 4,4′-diaminodiphenyl sulfide, and 4,4 ′. -Diaminodiphenyl sulfone, 3,3'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diaminobenzanilide, 4,4'-diaminodiphenyl ether, 1,5-diaminonaphthalene, 2,2'-dimethyl -4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 5-amino-1- (4'-aminophenyl) -1,3,3-trimethylindane, 6-amino -1- (4′-aminophenyl) -1,3,3-trimethylindane, 3,4′-diaminodiphenyl ether, 3,3′-di Aminobenzophenone, 3,4'-diaminobenzophenone, 4,4'-diaminobenzophenone, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) ) Phenyl] sulfone, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 4,4-bis ( 4-aminophenoxy) biphenyl, 9,9-bis (4-aminophenyl) -10-hydroanthracene, 2,7-diaminofluorene,

9,9-dimethyl-2,7-diaminofluorene, 9,9-bis (4-aminophenyl) fluorene, 4,4′-methylene-bis (2-chloroaniline), 2,2 ′, 5,5 ′ -Tetrachloro-4,4'-diaminobiphenyl, 2,2'-dichloro-4,4'-diamino-5,5'-dimethoxybiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 1 , 4,4 ′-(p-phenyleneisopropylidene) bisaniline, 4,4 ′-(m-phenyleneisopropylidene) bisaniline, 2,3-diaminopyridine, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 5,6-diamino-2,3-dicyanopyrazine, 5,6-diamino-2,4-dihydroxypyrimidine, 2,4-diamino- -Dimethylamino-1,3,5-triazine, 1,4-bis (3-aminopropyl) piperazine, 2,4-diamino-6-isopropoxy-1,3,5-triazine, 2,4-diamino- 6-methoxy-1,3,5-triazine, 2,4-diamino-6-phenyl-1,3,5-triazine, 2,4-diamino-6-methyl-s-triazine, 2,4-diamino- 1,3,5-triazine, 4,6-diamino-2-vinyl-s-triazine, 2,4-diamino-5-phenylthiazole, 2,6-diaminopurine, 5,6-diamino-1,3- Dimethyluracil, 3,5-diamino-1,2,4-triazole, 6,9-diamino-2-ethoxyacridine lactate, 3,8-diamino-6-phenylphenanthridine, 1,4-diamidine Piperazine, 3,6-diaminoacridine, bis (4-aminophenyl) phenylamine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, N-ethyl-3,6-diaminocarbazole, N- Phenyl-3,6-diaminocarbazole, N, N′-bis (4-aminophenyl) -benzidine, N, N′-bis (4-aminophenyl) -N, N′-dimethylbenzidine, the following formula (D— 15) and (D-16)

(Y in Formula (D-15) is an integer of 2-12, and z in Formula (D-16) is an integer of 1-5.)
And the like, and the like.
Examples of the aliphatic diamine include 1,1-metaxylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, 1, 3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, hexahydro-4,7-methanoindanylene methylene diamine, tricyclo [6.2.1.0 ^2,7 ] -undecylene dimethylene Diamines;
Examples of the alicyclic diamine include 1,4-diaminocyclohexane, isophorone diamine, tetrahydrodicyclopentadienylenediamine, 4,4′-methylenebis (cyclohexylamine), and the like:
Examples of the diaminoorganosiloxane include the following formula (D-VI):

(In the formula (D-VI), R ¹⁵ is a hydrocarbon group having 1 to 12 carbon atoms, and a plurality of R ¹⁵ may be the same or different, and p is 1 to 3 respectively. And q is an integer of 1 to 20.)
The compound etc. which are represented by these can be mentioned. Specific examples of the compound represented by the formula (D-VI) include 1,3-bis (3-aminopropyl) -tetramethyldisiloxane.
Among the above, the diamine used for synthesizing the polyamic acid used in the present invention is a compound represented by each of the above formulas (DI) to (D-IV);
An aromatic diamine having the fluorine atom;
Among the other aromatic diamines, p-phenylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl sulfide, 1,5-diaminonaphthalene, 2,2′-dimethyl-4,4′- Diaminobiphenyl, 2,7-diaminofluorene, 4,4′-diaminodiphenyl ether, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 9,9-bis (4-aminophenyl) fluorene, 4 , 4 ′-(p-phenylenediisopropylidene) bisaniline, 4,4 ′-(m-phenylenediisopropylidene) bisaniline, 1,4-bis (4-aminophenoxy) benzene, 4,4′-bis (4 -Aminophenoxy) biphenyl, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrim 3,6-diaminoacridine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, N-ethyl-3,6-diaminocarbazole and N-phenyl-3,6-diaminocarbazole, N , N′-di (4-aminophenyl) -benzidine and the compounds represented by the above formulas (D-15) and (D-16) respectively;
1,4-diaminocyclohexane and 1,3-bis (aminomethyl) cyclohexane among the above aliphatic diamines;
Selected from the group consisting of 4,4′-methylenebis (cyclohexylamine) of the alicyclic diamines; and 1,3-bis (3-aminopropyl) -tetramethyldisiloxane of the diaminoorganosiloxanes. It preferably contains at least one (hereinafter referred to as “specific diamine 1”).

The diamine used for synthesizing the polyamic acid used in the present invention preferably contains 5 mol% or more of the specific diamine 1 as described above, and more preferably contains 10 mol% or more of the total diamine. Preferably, the content is 20 mol% or more, more preferably 50 mol% or more.
Furthermore, when the liquid crystal aligning agent of this invention is used in order to form the liquid crystal aligning film for vertical alignment, the diamine used in order to synthesize | combine a polyamic acid is a said formula (D-III). And at least one selected from the group consisting of the compound represented by the formula (D-IV) (hereinafter referred to as “specific diamine 2-1”). The liquid crystal alignment film for vertical alignment to be formed further includes at least one selected from aromatic diamines having fluorine atoms (hereinafter referred to as “specific diamine 2-2”) together with the diamine 2-1. It is more preferable from the viewpoint of adhesion to the sealing agent.
When the liquid crystal aligning agent of the present invention is used for forming a liquid crystal alignment film for vertical alignment, the diamine used for synthesizing the polyamic acid is the specific diamine 2-1 as described above for all diamines. On the other hand, it is preferable to contain 8-40 mol%, and it is more preferable to contain 10-30 mol%. In this case, the diamine further preferably contains the specific diamine 2-2 in an amount of 0.2 to 40 mol%, more preferably 3 to 10 mol%, based on the total diamine.

[Synthesis of polyamic acid]
The polyamic acid used in the present invention can be synthesized by reacting the tetracarboxylic dianhydride as described above with a diamine.
The ratio of the tetracarboxylic dianhydride and the diamine compound used for the polyamic acid synthesis reaction is such that the acid anhydride group of the tetracarboxylic dianhydride is 0.1 relative to 1 equivalent of the amino group contained in the diamine compound. A ratio of 5 to 2 equivalents is preferable, and a ratio of 0.7 to 1.2 equivalents is more preferable.
The polyamic acid synthesis reaction is preferably performed in an organic solvent at a temperature of −20 to 150 ° C., more preferably 0 to 100 ° C., preferably 0.5 to 120 hours, more preferably 2 to 10 hours. Is called. Here, the organic solvent is not particularly limited as long as it can dissolve the synthesized polyamic acid. For example, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethyl sulfoxide And aprotic polar solvents such as γ-butyrolactone, tetramethylurea and hexamethylphosphortriamide; and phenol solvents such as m-cresol, xylenol, phenol and halogenated phenol. The amount of organic solvent used (α) is such that the total amount (β) of tetracarboxylic dianhydride and diamine compound is 0.1 to 30% by weight with respect to the total amount (α + β) of the reaction solution. It is preferable. The “amount of organic solvent used” in the above refers to the total amount of the organic solvent and the poor solvent when the organic solvent and the poor solvent described later are used in combination.

For the organic solvent, alcohol, ketone, ester, ether, halogenated hydrocarbon, hydrocarbon, etc., which are generally believed to be poor solvents for polyamic acid, may be used in combination as long as the resulting polyamic acid does not precipitate. it can. Specific examples of the poor solvent include, for example, methyl alcohol, ethyl alcohol, isopropyl alcohol, cyclohexanol, ethylene glycol, propylene glycol, 1,4-butanediol, triethylene glycol, ethylene glycol monomethyl ether, ethyl lactate, butyl lactate, Acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl acetate, ethyl acetate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, diethyl oxalate, diethyl malonate, diethyl ether, ethylene glycol methyl ether, ethylene Glycol ethyl ether, ethylene glycol-n-propyl ether, ethylene glycol-i-propyl ether, ethylene glycol-n- Chill ether, ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, tetrahydrofuran, dichloromethane, 1,2-dichloroethane, 1 , 4-dichlorobutane, trichloroethane, chlorobenzene, o-dichlorobenzene, hexane, heptane, octane, benzene, toluene, xylene, isoamylpropionate, isoamylisobutyrate, diisopentyl ether and the like.
When the organic solvent and the poor solvent as described above are used in combination, the use ratio of the poor solvent is preferably 50% by weight or less, more preferably 20% by weight or less, based on the total of the organic solvent and the poor solvent. Further, it is preferably 10% by weight or less.

  As described above, a reaction solution obtained by dissolving polyamic acid is obtained. This reaction solution may be used as it is for the preparation of the liquid crystal aligning agent, may be used for the preparation of the liquid crystal aligning agent after isolating the polyamic acid contained in the reaction solution, or the isolated polyamic acid was purified. You may use for preparation of a liquid crystal aligning agent. Polyamic acid can be isolated by pouring the reaction solution into a large amount of poor solvent to obtain a precipitate, and drying the precipitate under reduced pressure, or by distilling the reaction solution under reduced pressure using an evaporator. it can. Further, the polyamic acid can be purified by a method of dissolving the polyamic acid again in an organic solvent and then precipitating with a poor solvent, or a method of performing the step of distilling under reduced pressure with an evaporator once or several times.

<Imidized polymer>
The imidized polymer used in the present invention can be synthesized by dehydrating and ring-closing a polyamic acid obtained by reacting a tetracarboxylic dianhydride and a diamine.
[Tetracarboxylic dianhydride]
Examples of the tetracarboxylic dianhydride used for synthesizing the imidized polymer used in the present invention include the same compounds as the tetracarboxylic dianhydride used for the synthesis of the polyamic acid described above. Of these, alicyclic tetracarboxylic dianhydrides are preferred.
The tetracarboxylic dianhydride used for synthesizing the imidized polymer used in the present invention is 2,3,5-tricarboxycyclopentylacetic acid dianhydride among alicyclic tetracarboxylic dianhydrides. 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 1,3 , 3a, 4,5,9b-Hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 3-oxa Bicyclo [3.2.1] octane-2,4-dione-6-spiro-3 ′-(tetrahydrofuran-2 ′, 5′-dione), 5- (2,5-dioxotetrahydro-3-furanyl) -3-Methyl-3-cyclohexe -1,2-dicarboxylic anhydride, 3,5,6-tricarboxy-2-carboxynorbornane-2: 3,5: 6-dianhydride and 4,9-dioxatricyclo [5.3.1 .0 ^2,6] at least one selected from the group consisting of undecane -3,5,8,10- tetraone (hereinafter referred to. as "specific tetracarboxylic dianhydride 2") is preferably one containing. As the specific tetracarboxylic dianhydride 2, 2,3,5-tricarboxycyclopentylacetic acid dianhydride is particularly preferable.
The tetracarboxylic dianhydride used for synthesizing the imidized polymer used in the present invention is 10 mol of the specific tetracarboxylic dianhydride 2 as described above with respect to the total tetracarboxylic dianhydride. %, More preferably 20 mol% or more, and particularly preferably 50 mol% or more.
Examples of the diamine used for synthesizing the imidized polymer used in the present invention include the same compounds as the diamine used for the synthesis of the polyamic acid described above. Preferred diamines should also be understood in the same way as the diamines used in the synthesis of polyamic acids.

[Synthesis of imidized polymer]
The imidized polymer used in the present invention can be synthesized preferably by dehydrating and ring-closing the polyamic acid obtained by reacting the tetracarboxylic dianhydride and diamine as described above. The synthesis of the polyamic acid that is the precursor of the imidized polymer can be performed in the same manner as described above for the synthesis of the polyamic acid used in the present invention.
The dehydration ring closure reaction of the polyamic acid can be carried out by (i) heating the polyamic acid or (ii) dissolving the polyamic acid in an organic solvent, adding a dehydrating agent and a dehydrating ring closure catalyst to this solution, and heating as necessary. It can be performed by the method to do.
The reaction temperature in the method of heating the polyamic acid (i) is preferably 50 to 200 ° C, more preferably 60 to 170 ° C. When the reaction temperature is less than 50 ° C., the dehydration ring-closing reaction does not proceed sufficiently, and when the reaction temperature exceeds 200 ° C., the molecular weight of the imidized polymer obtained may decrease. The reaction time is preferably 1 to 120 hours, more preferably 2 to 30 hours.
In the method (ii) of adding a dehydrating agent and a dehydrating ring-closing catalyst to the polyamic acid solution, for example, an acid anhydride such as acetic anhydride, propionic anhydride, or trifluoroacetic anhydride can be used. . The amount of the dehydrating agent used is preferably 0.01 to 20 mol relative to 1 mol of the polyamic acid repeating unit. Moreover, as a dehydration ring closure catalyst, tertiary amines, such as a pyridine, a collidine, a lutidine, a triethylamine, can be used, for example. However, it is not limited to these. The amount of the dehydration ring-closing catalyst used is preferably 0.01 to 10 mol with respect to 1 mol of the dehydrating agent used. In addition, as an organic solvent used for dehydration ring closure reaction, the organic solvent illustrated as what is used for the synthesis | combination of a polyamic acid can be mentioned. And the reaction temperature of dehydration ring closure reaction becomes like this. Preferably it is 0-180 degreeC, More preferably, it is 10-150 degreeC. The reaction time is preferably 0.5 to 30 hours, more preferably 2 to 10 hours.

  The imidized polymer obtained in the above method (i) may be used as it is for the preparation of the liquid crystal aligning agent, or may be used for the preparation of the liquid crystal aligning agent after purifying the obtained polyimide. On the other hand, in the method (ii), a reaction solution containing an imidized polymer is obtained. This reaction solution may be directly used for the preparation of the liquid crystal aligning agent, or may be used for the preparation of the liquid crystal aligning agent after removing the dehydrating agent and the dehydrating ring-closing catalyst from the reaction solution. After separating, it may be used for preparing a liquid crystal aligning agent, or the isolated imidized polymer may be purified and then used for preparing a liquid crystal aligning agent. In order to remove the dehydrating agent and the dehydrating ring-closing catalyst from the reaction solution, for example, a method such as solvent replacement can be applied. Isolation and purification of the imidized polymer can be performed by performing the same operations as described above as the method for isolating and purifying the polyamic acid.

The imidized polymer used in the present invention may be a completely imidized product in which all of the amic acid structure of the polyamic acid as a precursor thereof is dehydrated and cyclized, or only a part of the amic acid structure is dehydrated. The ring may be closed and the amic acid structure and the imide ring may coexist and have a low imidization rate. The imidization rate of the imidized polymer used in the present invention is preferably 40% or more, more preferably 80 to 90%. Here, the “imidation rate” is a value representing the ratio of the number of imide rings to the total number of amic acid structures and imide rings in the imidized polymer as a percentage. At this time, a part of the imide ring may be an isoimide ring. The imidation rate of the imidized polymer is determined from ¹ H-NMR obtained by dissolving the imidized polymer in an appropriate deuterated solvent (for example, deuterated dimethyl sulfoxide) and measuring tetramethylsilane as a reference material at room temperature. Formula (i) below

Imidation ratio (%) = (1-A ¹ / A ² × α) × 100 ------ (i)

(In Formula (i), A ¹ is a peak area derived from protons of NH groups appearing in the vicinity of 10 ppm, A ² is a peak area derived from other protons, and α is a precursor of an imidized polymer (polyamic acid). The number ratio of other protons to one proton of NH group in)
Can be obtained.

[End-modified polymer]
The polyamic acid and the imidized polymer thereof may be of a terminal modified type with a controlled molecular weight. Such a terminal-modified type can be synthesized by adding an appropriate molecular weight regulator such as acid monoanhydride, monoamine compound, monoisocyanate compound to the reaction system when synthesizing the polyamic acid. Here, as the acid monoanhydride, for example, maleic anhydride, phthalic anhydride, itaconic anhydride, n-decyl succinic anhydride, n-dodecyl succinic anhydride, n-tetradecyl succinic anhydride , N-hexadecyl succinic anhydride and the like. Examples of the monoamine compound include aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, and n-undecyl. Amine, n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecylamine, n-octadecylamine, n-eicosylamine, etc. be able to. Examples of the monoisocyanate compound include phenyl isocyanate and naphthyl isocyanate.
The use ratio of these molecular weight regulators is preferably 20% by weight or less, more preferably 10% by weight or less, based on the total of tetracarboxylic dianhydride and diamine used when synthesizing the polyamic acid. is there.
[Solution viscosity]
The polyamic acid and the imidized polymer thereof preferably have a solution viscosity of 20 to 800 mPa · s, and have a solution viscosity of 30 to 500 mPa · s, respectively, when a 10% by weight solution is obtained. More preferably.
The solution viscosity (mPa · s) of the above polymer is E for a polymer solution having a concentration of 10% by weight prepared using a good solvent for the polymer (for example, N-methyl-2-pyrrolidone, γ-butyrolactone, etc.). It is a value measured at 25 ° C. using a mold rotational viscometer.

(B) Epoxy Compound Having Fluorine Atom The (b) epoxy compound having a fluorine atom contained in the liquid crystal aligning agent of the present invention is a compound having two epoxy groups and one or more fluorine atoms in the molecule. This fluorine atom is preferably present as a perfluoroalkyl group in the epoxy compound having a fluorine atom, and more preferably as a trifluoromethyl group. (B) The number of perfluoroalkyl groups in the epoxy compound having a fluorine atom is preferably 1 to 4, and more preferably 1 to 2. (B) The epoxy compound having a fluorine atom is preferably the following formula (B)

(In the formula (B), R is a divalent organic group.)
It is a compound represented by these. R in the formula (B) is preferably a divalent organic group having one or more alicyclic rings or aromatic rings. The alicyclic ring is preferably an alicyclic ring having 3 to 20 carbon atoms, and examples thereof include a cyclopentane ring and a cyclohexane ring. The aromatic ring is preferably an aromatic ring having 6 to 20 carbon atoms, and examples thereof include a benzene ring and a naphthalene ring anthracene ring. The total carbon number of divalent R is preferably 1-20, more preferably 2-12.
(B) Specific examples of the epoxy compound having a fluorine atom include, for example, 1- (diglycidylaminomethyl) -4-trifluoromethylbenzene, 1- (diglycidylaminomethyl) -3-trifluoromethylbenzene, 4- (Diglycidylaminomethyl) -4′-trifluoromethylbiphenyl, 4- (diglycidylaminomethyl) -4 ′-(trifluoromethyl) -diphenyl ether, N, N-diglycidyl-4-trifluoromethylaniline, N, N-diglycidyl-3-trifluoromethylaniline, 4- (diglycidylamino) -4′-trifluoromethylbiphenyl, 4- (diglycidylamino) -4 ′-(trifluoromethyl) -diphenyl ether, 4- (di Glycidylamino) -4 ′-(trifluoromethyl) -diphenylmethane 1- (diglycidylamino) -5-trifluoromethylnaphthalene, 2- (diglycidylamino) -6-trifluoromethylnaphthalene, 1- (diglycidylaminomethyl) -4-trifluoromethylcyclohexane, 1- (di Glycidylamino) -4-trifluoromethylcyclohexane, 1- (diglycidylamino) -3-trifluoromethylcyclohexane, 1- (diglycidylamino) -2-trifluoromethylcyclopentane,
1- (diglycidylaminomethyl) -4-trifluoromethoxybenzene, 1- (diglycidylaminomethyl) -3-trifluoromethoxybenzene, 4- (diglycidylaminomethyl) -4′-trifluoromethoxybiphenyl, 4 -(Diglycidylaminomethyl) -4 '-(trifluoromethoxy) -diphenyl ether, N, N-diglycidyl-4-trifluoromethoxyaniline, N, N-diglycidyl-3-trifluoromethoxyaniline, 4- (diglycidyl Amino) -4′-trifluoromethoxybiphenyl, 4- (diglycidylamino) -4 ′-(trifluoromethoxy) -diphenyl ether, 4- (diglycidylamino) -4 ′-(trifluoromethoxy) -diphenylmethane, 1 -(Diglycidylamino) -5-trifluoro Methoxynaphthalene, 2- (diglycidylamino) -6-trifluoromethoxynaphthalene, 1- (diglycidylaminomethyl) -4-trifluoromethoxycyclohexane, 1- (diglycidylamino) -4-trifluoromethoxycyclohexane, 1 -(Diglycidylamino) -3-trifluoromethoxycyclohexane, 1- (diglycidylaminomethyl) -4-trifluoromethoxycyclohexane, 1- (diglycidylamino) -2-trifluoromethoxycyclopentane and the like. it can.

Of these, 1- (diglycidylaminomethyl) -4-trifluoromethylbenzene, N, N-diglycidyl-4-trifluoromethylaniline, 1- (diglycidylaminomethyl) -4-trifluoromethylcyclohexane, 1 -(Diglycidylamino) -4-trifluoromethylcyclohexane, 1- (diglycidylaminomethyl) -4-trifluoromethoxybenzene, N, N-diglycidyl-4-trifluoromethoxyaniline, 1- (diglycidylaminomethyl) ) -4-trifluoromethoxycyclohexane and 1- (diglycidylamino) -4-trifluoromethoxycyclohexane, preferably 1- (diglycidylaminomethyl) -4-trifluoromethylbenzene, N, N-diglycidyl- 4-trifluoromethyl Aniline and 1 it is particularly preferred to use at least one selected from the group consisting of (diglycidyl aminomethyl) -4-trifluoromethyl-cyclohexane.
The use ratio of the epoxy compound having (b) a fluorine atom in the liquid crystal aligning agent of the present invention is preferably 0.01 to 40 parts by weight, more preferably 0.8 to 100 parts by weight of the polymer (a). It is 5-30 weight part, and it is preferable that it is 1-20 weight part further. By using this range, ODF is used as a liquid crystal filling method in the manufacturing process of the liquid crystal display element without causing adverse effects such as insufficient affinity with the liquid crystal, insufficient mechanical strength, and deterioration of electrical characteristics. When the method is adopted, the liquid crystal wettability can be improved, which is preferable. In addition, when (b) a part of the epoxy compound having a fluorine atom is replaced with another epoxy compound described below, the above-mentioned content ratio is different from the content ratio of the epoxy compound having a fluorine atom (b) It should be understood as the sum of the content of epoxy compounds.

In the liquid crystal aligning agent of this invention, in the range which does not impair the effect and advantage of this invention, you may replace and use a part of said (b) epoxy compound which has a fluorine atom with another epoxy compound. Examples of such other epoxy compounds include, for example, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1 , 6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 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 Examples include '-diaminodiphenylmethane, N, N-diglycidyl-benzylamine, N, N-diglycidyl-aminomethylcyclohexane, and the like.
In the liquid crystal aligning agent of the present invention, when (b) a part of the epoxy compound having a fluorine atom is replaced with another epoxy compound, the usage ratio of the other epoxy compound is (b) an epoxy compound having a fluorine atom. And preferably 90% by weight or less, more preferably 85% by weight or less, further preferably 80% by weight or less, and particularly preferably 50% by weight or less, based on the total of other epoxy compounds. . In the liquid crystal aligning agent of this invention, it is most preferable not to use another epoxy compound.

<Other ingredients>
Although the liquid crystal aligning agent of this invention contains the said (a) polymer and (b) the epoxy compound which has a fluorine atom as an essential component, it can contain other components arbitrarily. Examples of such other additives include functional silane compounds.
The functional silane compound can be added to improve the adhesion of the liquid crystal alignment film to be formed to the substrate surface. Examples of such functional silane compounds include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl)- 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyl Trimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1, , 7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N -Benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis (Oxyethylene) -3-aminopropyltrimethoxysilane, N-bis (oxyethylene) -3-aminopropyltriethoxysilane and the like can be mentioned. The use ratio of these functional silane compounds is preferably 2 parts by weight or less, more preferably 0.2 parts by weight or less with respect to 100 parts by weight of the polymer (a).

<Liquid crystal aligning agent>
The liquid crystal aligning agent of the present invention has a solution state in which the above (a) polymer and (b) an epoxy compound having a fluorine atom and other components optionally added are preferably dissolved in an organic solvent. Prepared.
As an organic solvent which can be used for the liquid crystal aligning agent of this invention, the solvent illustrated as what is used for the synthesis reaction of a specific polyamic acid can be mentioned. Moreover, the poor solvent illustrated as what can be used together in the case of the synthesis reaction of specific polyamic acid can also be selected suitably, and can be used together.
Particularly preferred organic solvents that can be used in the liquid crystal aligning agent of the present invention include, for example, N-methyl-2-pyrrolidone, γ-butyrolactone, γ-butyrolactam, N, N-dimethylformamide, N, N-dimethylacetamide, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol n-propyl ether, ethylene glycol-i-propyl ether, ethylene glycol-n-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethyl Examples include lenglycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, isoamyl propionate, isoamyl isobutyrate, and diisopentyl ether. These can be used alone or in admixture of two or more.

The solid content concentration in the liquid crystal aligning agent of the present invention (the ratio of the total weight of components other than the solvent of the liquid crystal aligning agent to the total weight of the liquid crystal aligning agent) can be appropriately set in consideration of viscosity, volatility, and the like. However, it is preferably in the range of 1 to 10% by weight. That is, the liquid crystal aligning agent of the present invention is applied to the substrate surface, and then the solvent is removed to form a coating film that becomes a liquid crystal aligning film, but the solid content concentration is less than 1% by weight. The film thickness of this coating film is too small to obtain a good liquid crystal alignment film, and when the solid content concentration exceeds 10% by weight, the film thickness of the coating film is too large to be equally good liquid crystal. It may be difficult to obtain an alignment film, or the viscosity of the liquid crystal aligning agent may increase, resulting in poor coating characteristics.
The particularly preferable solid content concentration range varies depending on the method used when the liquid crystal aligning agent is applied to the substrate. For example, when the spinner method is used, the range of 1.5 to 4.5% by weight is particularly preferable. In the case of the printing method, it is particularly preferable that the solid content concentration is in the range of 3 to 9% by weight, and thereby the solution viscosity is in the range of 12 to 50 mPa · s. In the case of the ink jet method, it is particularly preferable that the solid content concentration is in the range of 1 to 5% by weight, and thereby the solution viscosity is in the range of 3 to 15 mPa · s.
The temperature at which the liquid crystal aligning agent of the present invention is prepared is preferably 0 ° C to 200 ° C, more preferably 20 ° C to 60 ° C.

<Liquid crystal display element>
The liquid crystal display element of the present invention comprises a liquid crystal alignment film formed from the liquid crystal aligning agent of the present invention as described above.
The liquid crystal display element of the present invention can be produced, for example, by the following method.
First, the liquid crystal aligning agent of the present invention is applied to the transparent conductive film side of the substrate provided with the patterned transparent conductive film by an appropriate application method such as a roll coater method, a spinner method, a printing method, or an ink jet method. For example, the coating film is formed by heating at a temperature of 40 to 250 ° C. for 0.1 to 120 minutes. The thickness of the coating film is preferably 0.001 to 1 μm, more preferably 0.005 to 0.5 μm, as the thickness after removal of the solvent.
Examples of the substrate include glass such as float glass and soda glass, and a transparent substrate made of plastic such as polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polycarbonate, and poly (alicyclic olefin).
As the transparent conductive film, a NESA film made of SnO _{2 or} an ITO film made of In ₂ O ₃ —SnO ₂ can be used. In order to form these patterned transparent conductive films, a method of forming a pattern by a photo-etching method after forming a transparent conductive film without a pattern, and a mask having a desired pattern when forming the transparent conductive film A method of directly forming a patterned transparent conductive film using the method is used.
When applying the liquid crystal aligning agent, in order to further improve the adhesion between the substrate and the transparent conductive film and the coating film, a functional silane compound, titanate or the like is previously applied on the substrate and the transparent conductive film. Also good.

When the liquid crystal alignment film formed from the liquid crystal aligning agent of the present invention is used for a horizontal alignment type liquid crystal display element, a cloth made of fibers such as nylon, rayon, and cotton is then applied to the formed coating film surface. A rubbing process is performed by rubbing in a certain direction with a wound roll. By this rubbing treatment, the coating film is provided with an alignment ability of liquid crystal molecules to form a liquid crystal alignment film. Further, for example, Patent Document 6 (JP-A-6-222366) and Patent Document 7 (JP-A-6-281937) show liquid crystal alignment films formed with the liquid crystal aligning agent of the present invention. A process for changing the pretilt angle by irradiating a part of the liquid crystal alignment film with ultraviolet light, or a resist on a part of the surface of the liquid crystal alignment film as disclosed in Patent Document 8 (Japanese Patent Laid-Open No. 5-107544) It can be obtained by forming a film and performing a rubbing process in a direction different from the previous rubbing process, and then removing the resist film, so that the liquid crystal alignment film has a different liquid crystal alignment ability for each region. It is possible to improve the visual field characteristics of the horizontal liquid crystal display element.
On the other hand, when the liquid crystal alignment film is applied to a vertical alignment type liquid crystal display element, this rubbing treatment may not be performed.
A liquid crystal cell is manufactured by preparing two substrates on which a liquid crystal alignment film is formed as described above, and disposing a liquid crystal between the two substrates. In order to manufacture a liquid crystal cell, the following two methods are mentioned, for example.
The first method is a conventionally known method. First, two substrates are arranged to face each other through a gap (cell gap) so that the respective liquid crystal alignment films are opposed to each other, and the peripheral portions of the two substrates are bonded using a sealant, and the substrate surface and the sealant are bonded. A liquid crystal cell can be manufactured by injecting and filling liquid crystal into the cell gap partitioned by the step, and then sealing the injection hole.
The second method is a method called an ODF (One Drop Fill) method. For example, an ultraviolet light curable sealing material is applied to a predetermined location on one of the two substrates on which the liquid crystal alignment film is formed, and liquid crystal is dropped on the liquid crystal alignment film surface. The other substrate is bonded so as to face each other, and then the entire surface of the substrate is irradiated with ultraviolet light to cure the sealant, whereby a liquid crystal cell can be manufactured. The liquid crystal aligning agent of the present invention provides a liquid crystal aligning film having excellent liquid crystal wetting and spreading properties when used in the ODF method, and has the advantage of greatly reducing the process time in the liquid crystal filling step.
In any case, it is desirable to remove the flow alignment at the time of injection by heating the liquid crystal cell to a temperature at which the liquid crystal used has an isotropic phase and then slowly cooling it to room temperature.
And the liquid crystal display element of this invention can be obtained by bonding a polarizing plate on the outer surface of a liquid crystal cell.

As the sealing agent, for example, an aluminum oxide sphere as a spacer and an epoxy resin containing a curing agent can be used.
As the liquid crystal, for example, a nematic liquid crystal, a smectic liquid crystal, or the like can be used. When manufacturing a liquid crystal display element having a TN liquid crystal cell or an STN liquid crystal cell, a nematic liquid crystal having positive dielectric anisotropy (positive liquid crystal) is preferable, for example, a biphenyl liquid crystal or a phenylcyclohexane system. Liquid crystal, ester liquid crystal, terphenyl liquid crystal, biphenylcyclohexane liquid crystal, pyrimidine liquid crystal, dioxane liquid crystal, bicyclooctane liquid crystal, cubane liquid crystal and the like are used. Cholesteric liquid crystals such as cholesteryl chloride, cholesteryl nonate, and cholesteryl carbonate; chiral agents such as those sold under the trade names “C-15” and “CB-15” (manufactured by Merck); p- A ferroelectric liquid crystal such as decyloxybenzylidene-p-amino-2-methylbutylcinnamate may be further added and used.
On the other hand, in the case of a vertical alignment type liquid crystal cell, a nematic type liquid crystal having negative dielectric anisotropy (negative type liquid crystal) is preferable. For example, dicyanobenzene liquid crystal, pyridazine liquid crystal, Schiff base liquid crystal, azoxy liquid crystal Type liquid crystal, biphenyl type liquid crystal, phenylcyclohexane type liquid crystal and the like are used.
The polarizing plate used outside the liquid crystal cell is composed of a polarizing film called “H film” in which polyvinyl alcohol is stretched and oriented while absorbing iodine and sandwiched between cellulose acetate protective films, or the H film itself. A polarizing plate etc. can be mentioned.
The liquid crystal display element of the present invention thus produced does not have a display defect due to liquid crystal alignment unevenness and exhibits excellent display quality.

In the following synthesis examples, the solution viscosity of the polymer solution is a value measured at 25 ° C. using an E-type viscometer.
Imidization ratio of imidization polymer was thoroughly dried under reduced pressure imidized polymer at room temperature, dissolved in deuterated dimethyl sulfoxide, from the equation ^{1 H-NMR} was measured using tetramethylsilane as a standard substance ( determined by i).
<Synthesis of polyamic acid>
Synthesis example 1
110 g (0.50 mol) of pyromellitic dianhydride as tetracarboxylic dianhydride and 98 g (0.50 mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride and 4,4- as diamine 200 g (1.0 mol) of diaminodiphenyl ether was dissolved in a mixed solvent consisting of 230 g of N-methyl-2-pyrrolidone and 2,060 g of γ-butyrolactone, reacted at 40 ° C. for 3 hours, and then 1,350 g of γ-butyrolactone. As a result, about 3,900 g of a solution containing 10% by weight of polyamic acid (A-1) was obtained. The solution viscosity of this polyamic acid solution was 200 mPa · s.

Synthesis example 2
1,2,3,4-Cyclobutanetetracarboxylic dianhydride 98 g (0.50 mol) and pyromellitic dianhydride 110 g (0.50 mol) as tetracarboxylic dianhydride and 4,4 ′ as diamine -200 g (1.0 mol) of diaminodiphenylmethane was dissolved in a mixed solvent consisting of 230 g of N-methyl-2-pyrrolidone and 2,060 g of γ-butyrolactone, reacted at 40 ° C. for 3 hours, then γ-butyrolactone 1, By adding 350 g, about 4,000 g of a solution containing 10% by weight of polyamic acid (A-2) was obtained. The solution viscosity of this polyamic acid solution was 125 mPa · s.
Synthesis example 3
200 g (1.0 mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as tetracarboxylic dianhydride and 200 g (1.0 mol) of 4,4′-diaminodiphenyl ether as diamine were added to N-methyl. After dissolving in a mixed solvent consisting of 230 g of 2-pyrrolidone and 2,020 g of γ-butyrolactone and reacting at 40 ° C. for 4 hours, 1,300 g of γ-butyrolactone was added to obtain polyamic acid (A-3) About 3,900 g of a solution containing 10% by weight was obtained. The solution viscosity of this polyamic acid solution was 210 mPa · s.

Synthesis example 4
200 g (1.0 mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as tetracarboxylic dianhydride and 210 g of 2,2′-dimethyl-4,4′-diaminobiphenyl as diamine (1. 0 mol) is dissolved in a mixed solvent composed of 370 g of N-methyl-2-pyrrolidone and 3,300 g of γ-butyrolactone, and reacted at 40 ° C. for 3 hours to contain 10% by weight of polyamic acid A-4 4,000 g was obtained. The solution viscosity of this polyamic acid solution was 160 mPa · s.
Synthesis example 5
2,3,5-Tricarboxycyclopentyl acetic acid dianhydride 220 g (1.0 mol) as tetracarboxylic dianhydride and 200 g (1.0 mol) of 4,4′-diaminodiphenyl ether as diamine were added to N-methyl-2 -It dissolved in a mixed solvent consisting of 240 g of pyrrolidone and 2,200 g of γ-butyrolactone and reacted at 40 ° C for 4 hours to obtain about 4,700 g of a solution containing polyamic acid (A-5). A small amount of this solution was collected, and γ-butyrolactone was added thereto, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 38 mPa · s.

Synthesis Example 6
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro -2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione 160 g (0.50 mol) and p-phenylenediamine 95 g (0.88 mol) as diamine, 2,2-ditrifluoromethyl-4,4-diaminobiphenyl 32 g (0.10 mol), 3,6-bis (4-aminobenzoyloxy) cholestane (compound represented by the above formula (D-1). The same.) 6.4 g (0.010 mol) and octadecanoxy-2,5-diaminobenzene 4.0 g (0.015 mol) were added to N-methyl-2-pyrrolidone 9 Was dissolved in 0 g, it was subjected to 9 hours at 60 ° C.. A small amount of the obtained polyamic acid solution was collected, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 58 mPa · s.
To the obtained polyamic acid solution, 2,740 g of N-methyl-2-pyrrolidone, 400 g of pyridine, and 410 g of acetic anhydride were added, and a dehydration ring-closing reaction was performed at 110 ° C. for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with new γ-butyrolactone (the pyridine and acetic anhydride used for the imidization reaction were removed from the system in this operation. The same applies hereinafter). About 2,500 g of a solution containing 15% by weight of the imidized polymer (B-1) having a rate of about 95% was obtained. A small amount of this solution was collected, and γ-butyrolactone was added thereto, and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight was 69 mPa · s.

Synthesis example 7
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro -2,5-dioxo-3-furanyl) naphtho [1,2-c] furan-1,3-dione 160 g (0.50 mol), p-phenylenediamine 96 g (0.89 mol) as diamine, bisamino 25 g (0.10 mol) of propyltetramethyldisiloxane and 13 g (0.020 mol) of 3,6-bis (4-aminobenzoyloxy) cholestane and 8.1 g (0.030 mol) of N-octadecylamine as monoamine The product was dissolved in 960 g of N-methyl-2-pyrrolidone and reacted at 60 ° C. for 6 hours. A small amount of the obtained polyamic acid solution was collected, and N-methyl-2-pyrrolidone was added to measure the solution viscosity as a solution having a polyamic acid concentration of 10% by weight of 60 mPa · s.
Next, 2,700 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 400 g of pyridine and 410 g of acetic anhydride were further added, and dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration cyclization reaction, the solvent in the system was replaced with new γ-butyrolactone to obtain about 2,400 g of a solution containing 15% by weight of an imidized polymer (B-2) having an imidization ratio of about 95%. Obtained. A small amount of this solution was collected, and γ-butyrolactone was added thereto, and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight was 70 mPa · s.

Synthesis Example 8
220 g (1.0 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 110 g (0.99 mol) of p-phenylenediamine and 3,6-bis (4- Aminobenzoyloxy) cholestane 6.4 g (0.010 mol) is dissolved in 3,040 g of N-methyl-2-pyrrolidone and reacted at 60 ° C. for 6 hours to give a polyamic acid solution having a solution viscosity of about 260 mPa · s. Got.
Next, 2,700 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 400 g of pyridine and 310 g of acetic anhydride were further added, and a dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration cyclization reaction, the solvent in the system was replaced with new γ-butyrolactone to obtain about 2,900 g of a solution containing 10% by weight of imidized polymer (B-3) having an imidization ratio of about 89%. Obtained. The solution viscosity of this solution was 300 mPa · s.

Synthesis Example 9
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 1,3,3a, 4,5,9b-hexahydro-8-methyl-5 (tetrahydro- 2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione 160 g (0.50 mol) and p-phenylenediamine 89 g (0.82 mol) as diamine, 2 , 2′-ditrifluoromethyl-4,4′-diaminobiphenyl 32 g (0.10 mol), 1- (3,5-diaminobenzoyloxy) -4- (4-trifluoromethylbenzoyloxy) -cyclohexane (above Compound represented by the formula (D-14).) 25 g (0.059 mol) and octadecanoxy-2,5-diaminobenzene 4.0 g (0. 11 mol) was dissolved in N- methyl-2-pyrrolidone 2,180G, it was 6 hours at 60 ° C.. A small amount of the obtained polyamic acid solution was collected, and N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 110 mPa · s.
1,500 g of the resulting polyamic acid solution was taken, 3,000 g of N-methyl-2-pyrrolidone was added thereto, 221 g of pyridine and 228 g of acetic anhydride were added, and dehydration ring closure reaction was performed at 110 ° C. for 4 hours. It was. After the dehydration and cyclization reaction, the solvent in the system was replaced with new γ-butyrolactone to obtain about 2,500 g of a solution containing 10% by weight of imidized polymer (B-4) having an imidization rate of about 92%. Obtained. The solution viscosity of this solution was 130 mPa · s.

Synthesis Example 10
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 43 g (0.40 mol) of p-phenylenediamine and 3 (3,5-diaminobenzoyl) as diamine Oxy) cholestane 52 g (0.10 mol) was dissolved in 830 g of N-methyl-2-pyrrolidone and reacted at 60 ° C. for 6 hours. A small amount of the obtained polyamic acid solution was collected, and N-methyl-2-pyrrolidone was added to measure the solution viscosity as a solution having a polyamic acid concentration of 10% by weight of 60 mPa · s.
Next, 1,900 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 40 g of pyridine and 51 g of acetic anhydride were further added, and a dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with new N-methyl-2-pyrrolidone to obtain a solution containing about 15% by weight of imidized polymer (B-5) having an imidization ratio of about 50%. 1,200 g was obtained. A small amount of this solution was taken and N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight was 47 mPa · s.

Synthesis Example 11
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 49 g (0.45 mol) and 3 (3,5-diaminobenzoyl) of p-phenylenediamine as diamine 26 g (0.05 mol) of oxy) cholestane was dissolved in 750 g of N-methyl-2-pyrrolidone and reacted at 60 ° C. for 6 hours. A small amount of the obtained polyamic acid solution was collected, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 58 mPa · s.
Next, 1,800 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 40 g of pyridine and 51 g of acetic anhydride were further added, and a dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration ring-closure reaction, the solvent in the system was replaced with new N-methyl-2-pyrrolidone, whereby a solution containing about 15% by weight of an imidized polymer (B-6) having an imidization ratio of about 50%. 1,100 g was obtained. A small amount of this solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight was 85 mPa · s.

Synthesis Example 12
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride, 38 g (0.35 mol) of p-phenylenediamine as diamine, 20 g of 4,4′-diaminodiphenylmethane (0.1 mol) and 26 g (0.05 mol) of 3 (3,5-diaminobenzoyloxy) cholestane were dissolved in 750 g of N-methyl-2-pyrrolidone and reacted at 60 ° C. for 6 hours. A small amount of the obtained polyamic acid solution was collected, and N-methyl-2-pyrrolidone was added to measure the solution viscosity as a solution having a polyamic acid concentration of 10% by weight of 60 mPa · s.
Next, 1,800 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 40 g of pyridine and 51 g of acetic anhydride were further added, and a dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with new γ-butyrolactone to obtain about 1,150 g of a solution containing 15% by weight of an imidized polymer (B-7) having an imidization ratio of about 50%. Obtained. A small amount of this solution was collected, and γ-butyrolactone was added thereto, and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight was 87 mPa · s.
Synthesis Example 13
77 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 30 g (0.40 mol) of p-phenylenediamine as diamine and the above formula (D-3) 34 g (0.1 mol) of the compound represented was dissolved in 560 g of N-methyl-2-pyrrolidone and reacted at 60 ° C. for 4 hours. A small amount of the obtained polyamic acid solution was collected, and N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 137 mPa · s.
Next, 1,300 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 27 g of pyridine and 35 g of acetic anhydride were further added, and dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with new N-methyl-2-pyrrolidone, whereby a solution containing 13% by weight of imidized polymer (B-8) having an imidization ratio of about 50% was obtained. 710 g was obtained. A small amount of this solution was taken and N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight was 98 mPa · s.

Synthesis Example 14
74 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 27 g (0.375 mol) of p-phenylenediamine as diamine, in the above formula (D-3) 33 g (0.1 mol) of the compound represented and 7 g (0.025 mol) of the compound represented by the above formula (D-12) were dissolved in 560 g of N-methyl-2-pyrrolidone and reacted at 60 ° C. for 4 hours. Went. A small amount of the obtained polyamic acid solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 124 mPa · s.
Next, 1,300 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 26 g of pyridine and 34 g of acetic anhydride were further added, and a dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with new N-methyl-2-pyrrolidone, whereby a solution containing 17% by weight of an imidized polymer (B-9) having an imidization ratio of about 50% was obtained. 660 g was obtained. A small amount of this solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight was 90 mPa · s.
Synthesis Example 15
75 g (0.50 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride and 27 g (0.375 mol) of p-phenylenediamine as diamine, in the above formula (D-3) 25 g (0.075 mol) of the compound represented, 5.0 g of 2,2′-trifluoromethyl-4,4′-diaminobiphenyl (0.025 mol) and 4- (4′-trifluoromethylbenzoyloxy) ) 7.0 g of cyclohexyl-3,5-diaminobenzoate (0.025 mol) was dissolved in 560 g of N-methyl-2-pyrrolidone and reacted at 60 ° C. for 4 hours. A small amount of the obtained polyamic acid solution was collected, and N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 110 mPa · s.
Next, 1,300 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 27 g of pyridine and 34 g of acetic anhydride were further added, and a dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with new N-methyl-2-pyrrolidone, whereby a solution containing about 16% by weight of the imidized polymer (B-10) having an imidization ratio of about 50%. 700 g was obtained. A small amount of this solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight was 87 mPa · s.

Synthesis Example 16
69 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 21 g (0.325 mol) of p-phenylenediamine as a diamine, in the above formula (D-3) 23 g (0.075 mol) of the compound represented and 26 g (0.10 mol) of the compound represented by the above formula (D-12) were dissolved in 560 g of N-methyl-2-pyrrolidone and reacted at 60 ° C. for 4 hours. Went. A small amount of the obtained polyamic acid solution was collected, and N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 119 mPa · s.
Next, 1,300 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 24 g of pyridine and 32 g of acetic anhydride were further added, and a dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with new N-methyl-2-pyrrolidone, whereby a solution containing about 16% by weight of the imidized polymer (B-11) having an imidization ratio of about 50%. 650 g was obtained. A small amount of this solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight was 84 mPa · s.

Example 1
<Preparation of liquid crystal aligning agent>
The amount corresponding to 80 parts by weight in terms of the polyamic acid (A-1) in the solution containing the polyamic acid (A-1) obtained in Synthesis Example 1 and the imidized polymer obtained in Synthesis Example 6 ( In combination with the amount corresponding to 20 parts by weight of the imidized polymer (B-1) of the solution containing B-1), 1- (diglycidylaminomethyl) is used as an epoxy compound having a fluorine atom. 10 parts by weight of -4-trifluoromethylbenzene is added, and a mixed solvent composed of N-methyl-2-pyrrolidone (NMP) and butyl cellosolve (BC) (mixing ratio is NMP: BC = 50: 50 (weight ratio)). .) Was added to obtain a solution having a solid concentration of 3% by weight. About this solution, the liquid crystal aligning agent was prepared by filtering using a filter with a hole diameter of 1 micrometer. This liquid crystal aligning agent was evaluated as follows.
<Evaluation of liquid crystal wettability>
The liquid crystal aligning agent prepared above is applied by spin coating on the transparent electrode surface of a glass substrate with a transparent electrode made of an ITO film, pre-baked on an 80 ° C. hot plate for 1 minute, and further on a 200 ° C. hot plate. Was post-baked for 10 minutes to form a coating film having an average film thickness of 600 mm.
On this coating film, 5 μL of liquid crystal (MLC-6221, manufactured by Merck & Co., Ltd.) was dropped, and the contact angle between the coating film and the liquid crystal was measured. The contact angle was 12.4 °.
The present inventors have found that the time required for the liquid crystal filling step when the liquid crystal dropping method (ODF method) is adopted depends on the affinity between the liquid crystal alignment film and the liquid crystal. Further, when the contact angle is 13 ° or less, the wettability of the liquid crystal is good. In such a case, the knowledge that the time required for the liquid crystal filling process can be sufficiently shortened has been obtained empirically.

<Manufacture of TN type liquid crystal cell>
Using the liquid crystal aligning agent prepared above, a coating film having an average film thickness of 600 mm was formed on the transparent electrode surface of the glass substrate with a transparent electrode made of an ITO film in the same manner as in the above <Evaluation of liquid crystal wetting and spreading>. . This coating film is rubbed with a rubbing machine having a roll wrapped with rayon cloth at a roll rotation speed of 500 rpm, a stage moving speed of 3 cm / sec, and a hair foot indentation length of 0.4 mm to give liquid crystal alignment ability. And it was set as the liquid crystal aligning film. These operations were repeated to obtain a pair (two) of substrates having a liquid crystal alignment film on the transparent electrode surface.
Next, an epoxy resin adhesive containing aluminum oxide spheres having a diameter of 5.5 μm is applied to the outer edges of the surfaces of the pair of substrates having the liquid crystal alignment film, and then each liquid crystal alignment film surface has a rubbing direction of 90%. The adhesive was hardened by overlapping and pressing so as to be at a relative angle. Next, a nematic liquid crystal (MLC-6221, manufactured by Merck & Co., Inc.) was filled between the pair of substrates from the liquid crystal inlet, and then the liquid crystal inlet was sealed with an acrylic photo-curing adhesive to produce a liquid crystal cell. .
<Evaluation of liquid crystal alignment>
The liquid crystal cell was observed for the presence or absence of an abnormal domain when a voltage of 5 V was turned on / off (applied / released) at room temperature with a polarizing microscope. The liquid crystal alignment of the liquid crystal cell was “good”.
<Evaluation of voltage holding ratio>
For the liquid crystal cell produced above, a voltage of 5 V was applied at 60 ° C. with an application time of 60 microseconds and a span of 167 milliseconds, and then the voltage holding ratio after 167 milliseconds after application release was measured. The voltage holding ratio of the liquid crystal cell was 99.0%. For measurement of the voltage holding ratio, model “VHR-1” manufactured by Toyo Corporation was used.
<Measurement of residual voltage>
A direct current of 17.0 V was applied to the liquid crystal cell produced above at 100 ° C. for 20 hours. Immediately after the application of the DC voltage was released, the mixture was allowed to cool at room temperature for 15 minutes, and then the voltage remaining in the liquid crystal cell was determined by the flicker erasing method. At this time, when the residual voltage was 800 mV or less, the residual voltage was evaluated as “good”. As a result, the residual voltage of the liquid crystal cell was “good”.

Examples 2-12
As the solution containing the polyamic acid and the solution containing the imidized polymer as the solution containing the polymer shown in Table 1, respectively, the type and amount of the epoxy compound having a fluorine atom are shown in Table 1, respectively. A liquid crystal aligning agent was prepared and evaluated in the same manner as in Example 1 except that. The results are shown in Table 1.
In Table 1, the abbreviations of the types of epoxy compounds having a fluorine atom have the following meanings.
E-1: 1- (Diglycidylaminomethyl) -4-trifluoromethylbenzene E-2: 1- (Diglycidylaminomethyl) -4-trifluoromethylcyclohexane Comparative Examples 1-6
A solution containing a polymer shown in Table 2 is used as a solution containing a polyamic acid and a solution containing an imidized polymer, respectively, and is an epoxy compound having no fluorine atom instead of an epoxy compound having a fluorine atom. A liquid crystal aligning agent was prepared and evaluated in the same manner as in Example 1 except that N, N, N ′, N′-tetraglycidyl-4,4′-diaminodiphenylmethane was used in the amount shown in Table 2. The results are shown in Table 2.

Example 13
<Preparation of liquid crystal aligning agent>
In an amount equivalent to 100 parts by weight in terms of the imidized polymer (B-5) of the solution containing the imidized polymer (B-5) obtained in Synthesis Example 10, the fluorine atom is contained here. 5 parts by weight of 1- (diglycidylaminomethyl) -4-trifluoromethylbenzene is added as an epoxy compound, and a mixed solvent composed of N-methyl-2-pyrrolidone (NMP) and butyl cellosolve (BC) (mixing ratio is NMP: BC = 50: 50 (weight ratio)) was added to obtain a solution having a solid content concentration of 2.5% by weight. About this solution, the liquid crystal aligning agent was prepared by filtering using a filter with a hole diameter of 1 micrometer. This liquid crystal aligning agent was evaluated as follows.
<Evaluation of liquid crystal wettability>
The contact angle between the coating film and the liquid crystal was the same as in <Evaluation of liquid crystal wetting and spreading> in Example 1 except that the liquid crystal aligning agent prepared above was used and the liquid crystal used was MLC-6608 manufactured by Merck. Was measured. The results are shown in Table 3.

<Evaluation of adhesion of liquid crystal alignment film>
By applying the liquid crystal aligning agent prepared above onto one side of a rectangular glass substrate by spin coating, pre-baking on an 80 ° C. hot plate for 1 minute, and further post-baking on a 200 ° C. hot plate for 10 minutes. A coating film having an average film thickness of 600 mm was formed. The same operation was repeated to obtain a pair (two) of rectangular glass substrates having a coating film on one side.
Take one of the substrates having the coating film formed above, and sealant (ultraviolet curable sealant containing 2.0% by weight of a spherical spacer with a diameter of 3.5 μm) at the approximate center of the coating surface 0 .1 mg was added dropwise. On top of this, another substrate is stacked so that the coating surface faces each other, and both substrates are twisted in opposite directions in a plane horizontal to the coating surface while both substrates are crimped manually. A cross shape with the dropping point of the sealing agent as a connecting portion is formed. By this operation, the sealing agent was pushed out into a circular shape having a diameter of 4.8 to 5.2 mm. Next, after irradiating it with 100 mW ultraviolet rays containing a 365 nm emission line for 30 seconds, the sample was heated in an oven at 120 ° C. for 1 hour to cure the sealant, thereby preparing a sample for evaluating adhesion.
About this sample, the adhesiveness of the coating film was investigated as follows using the tensile compression tester (model number "SDWS-0201-100SL") by Imada Manufacturing Co., Ltd.
The above sample is placed on the U-shaped gantry of the measuring device, one of the substrates is held horizontally on the gantry at both ends outside the cruciform contact (center), and the other substrate is It installed so that it might become below a holding substrate, without contacting a mount. Next, a U-shaped pressing jig was placed on the placed sample so that only both end portions outside the cross-shaped contact portion (center portion) of the lower substrate could be pushed downward. In this state, pressure was applied to the pressing jig from above, and a force was applied in a direction to separate the two glass substrates adhered through the coating film and the sealant. At this time, the force (F _sam ) required to break the adhesive interface of the substrate was examined.
On the other hand, using a glass substrate on which no coating film was formed, a sample for evaluating adhesion was prepared in the same manner as described above, and the adhesion was evaluated, and the force required to destroy the adhesion interface of the substrate (F _ref ) was examined.
The value obtained by dividing F _sam by F _ref is shown in Table 3 as an index of adhesion.
Note that F _sam and F _ref are values obtained as average values of five measurement points.

<Manufacture and evaluation of VA type liquid crystal cell>
In <Manufacture of TN liquid crystal cell> in Example 1, except that the rubbing treatment was not performed and the liquid crystal used was MLC-6608 manufactured by Merck & Co., Ltd. Thus, a VA type liquid crystal cell was manufactured.
The liquid crystal cell was evaluated for liquid crystal orientation, voltage holding ratio, and residual voltage in the same manner as in Example 1. These evaluation results are shown in Table 3.

Examples 14-46
Example 1 except that the solution containing the polymer shown in Table 3 was used as the solution containing the imidized polymer, and the type and amount of the epoxy compound having a fluorine atom were as shown in Table 1, respectively. Similarly, liquid crystal aligning agents were prepared and evaluated. The results are shown in Table 3.
The abbreviations for the types of epoxy compounds having fluorine atoms in Table 3 have the same meanings as in Table 1.
Comparative Examples 7 to 27
A solution containing the polymer shown in Table 4 is used as the solution containing the imidized polymer, and N, N, N ′, N which is an epoxy compound having no fluorine atom instead of the epoxy compound having a fluorine atom A liquid crystal aligning agent was prepared and evaluated in the same manner as in Example 13 except that '-tetraglycidyl-4,4'-diaminodiphenylmethane was used in the amount shown in Table 4. The results are shown in Table 4.

Claims (8)

(A) at least one polymer selected from the group consisting of a polyamic acid obtained by reacting a tetracarboxylic dianhydride and a diamine and an imidized polymer thereof , provided that the tetracarboxylic dianhydride is butane Tetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3 , 4-Cyclopentanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo -3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro 2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5,8-dimethyl-5- ( Tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, bicyclo [2.2.2] -oct-7-ene-2,3,5 6-tetracarboxylic dianhydride, 3-oxabicyclo [3.2.1] octane-2,4-dione-6-spiro-3 ′-(tetrahydrofuran-2 ′, 5′-dione), 5- ( 2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, 3,5,6-tricarboxy-2-carboxynorbornane-2: 3,5: 6-dianhydride, 4,9-dioxatricyclo [5.3 1.0 ^2,6] undecane -3,5,8,10- tetraone, pyromellitic dianhydride, 3,3 ', 4,4'-benzophenone tetracarboxylic dianhydride, 3,3', 4 , 4′-biphenylsulfonetetracarboxylic dianhydride, 2,2 ′, 3,3′-biphenyltetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, T-5) to (T-8)

And at least one selected from the group consisting of the compounds represented by each of the formula (1 ) comprises 10 mol% or more based on the total tetracarboxylic dianhydride , and (b) two epoxy groups and one in the molecule The liquid crystal aligning agent characterized by including the compound which has the above fluorine atoms. The diamine is
The following formulas (D-III) and (D-IV)

(R ^{9 in} formula (D-III) is a monovalent organic group having a steroid skeleton, and X ³ is a single bond, —O— ^* , —COO— ^* , —OCO— ^* , —NHCO— ^* , -CONH- ^* or -CO- ^* (wherein "*" a bond marked is bonded to ^{R 9.)} a ^{and, R 10} is an alkyl group having 1 to 4 carbon atoms, a3 0-3 Is an integer,
R ¹¹ in the formula (D-IV) is a divalent organic group having a steroid skeleton, and X ⁴ is —O— ^* , —COO— ^* , —OCO— ^* , —NHCO— ^* , — CONH- ^* or -CO- ^* (However, bond marked with "*" is. to bind to ^{R 11) is, R 12} are each an alkyl group having 1 to 4 carbon atoms, a4 is Each is an integer from 0 to 4. )
Of those containing at least one selected from the group consisting of compounds represented by each used to form a vertical alignment liquid crystal alignment film, liquid crystal aligning agent of claim 1.   The liquid crystal aligning agent according to claim 2, wherein the diamine further contains an aromatic diamine having a fluorine atom. The tetracarboxylic acid dianhydride, 2,3,5-carboxy is intended to include cyclopentyl acetic dianhydride, liquid crystal alignment agent according to any one of claims 1-3. The component (b) is represented by the following formula (B)

(In the formula (B), R is a divalent organic group.)
The liquid crystal aligning agent as described in any one of Claims 1-4 which is a compound represented by these.   The liquid crystal aligning agent of Claim 5 in which group R in the said Formula (B) has a 1 or more alicyclic ring or an aromatic ring.   The liquid crystal aligning agent as described in any one of Claims 1-6 which contains 0.01-40 weight part of components (b) with respect to 100 weight part of components (a). A liquid crystal display element comprising a liquid crystal alignment film formed from the liquid crystal aligning agent according to claim 1.