KR20060127782A - Liquid crystal aligning agent and liquid crystal display device - Google Patents

Abstract

Provided is a liquid crystal aligning agent, which shows excellent vertical aligning property and voltage maintaining characteristics and high adhesion to an encapsulating agent, and is useful for the fabrication of a liquid crystal display device having good rigidity and high image quality. The liquid crystal aligning agent comprises any one of a polyamic acid obtained by reacting a first diamine represented by the following formula 1, a second diamine other than the first diamine, represented by the formula of H2N-R2-NH2 (wherein R2 is a divalent organic group), and tetracarboxylic dianhydride, and an imidized polymer obtained by dehydrocyclization of the polyamic acid. In the formula 1, R1 represents a group represented by any one of the following formulae 1-1 to 1-4.

Description

Liquid crystal aligning agent and liquid crystal display element {LIQUID CRYSTAL ALIGNING AGENT AND LIQUID CRYSTAL DISPLAY DEVICE}

[Patent Document 1] Japanese Unexamined Patent Publication No. 6-136122

[Patent Document 2] Japanese Patent No. 2893671

[Patent Document 3] Japanese Unexamined Patent Application Publication No. 2004-331937

[Patent Document 4] Japanese Patent Application Laid-Open No. 2004-262921

The present invention relates to a vertical alignment liquid crystal aligning agent and a liquid crystal display device. More specifically, the present invention relates to a novel liquid crystal aligning agent excellent in printability, vertical alignment property, voltage holding property, sealant adhesiveness, and a liquid crystal display device that is robust and has a beautiful image.

Conventionally, the nematic liquid crystal layer which has positive dielectric anisotropy is formed between two board | substrates with which the liquid crystal aligning film containing a polyamic acid or a polyimide is formed on the surface through a transparent conductive film, and has a sandwich structure, The said liquid crystal molecule BACKGROUND ART A liquid crystal display device having a TN (Twisted Nematic) type or STN (Super Twisted Nematic) type liquid crystal cell in which the major axis of is continuously twisted by 90 degrees or more between substrates is known. The so-called TFT liquid crystal panel which operated this TN type liquid crystal display element by TFT drive is widely used instead of the conventional CRT. The liquid crystal orientation in these liquid crystal display elements is normally implement | achieved by the liquid crystal aligning film in which the orientation ability of liquid crystal molecules was provided by the rubbing process etc. In addition, a liquid crystal display having a vertical alignment liquid crystal cell in which liquid crystal molecules having negative dielectric anisotropy are vertically oriented to the substrate (providing a 90 degree pretilt angle) as a liquid crystal display element separate from the above. The device is known. Also in such a liquid crystal display element, the orientation control of a liquid crystal is normally performed by the liquid crystal aligning film formed by the liquid crystal aligning agent containing polymers, such as a polyamic acid and polyimide.

The pretilt angle is a monomer having a bulky density substituent in the side chain, such as 1-octadecyloxy-2,4-diaminobenzene, as disclosed in Japanese Patent Laid-Open No. 6-136122 (hereinafter, Expression) by introducing a pretilt angle expressing monomer into the polymer. In addition, Japanese Patent No. 2893671 and Japanese Patent Laid-Open No. 2004-331937 disclose cholesteryl, 3,5-diaminobenzoate, litocholic acid stearyl (3,5-diaminobenzoate), and cholestera. Neyl-3,5-diaminobenzoate and the like are disclosed, and Japanese Patent Laid-Open No. 2004-262921 discloses a plurality of pretilt-angle expression monomers including cholesteryloxy-2,4-diaminobenzene. Is disclosed. The liquid crystal aligning agent which provides a stable pretilt angle by the polymer using these can be manufactured.

Basic characteristics required for the liquid crystal alignment film used in the liquid crystal display device having a vertically aligned liquid crystal cell include printability, vertical alignment, voltage retention characteristics, and the like. In order for the sealing agent to adhere to reach a liquid crystal aligning film application area | region, the improvement of adhesiveness with a sealing agent is calculated | required by the liquid crystal aligning film.

This invention is made | formed based on the above circumstances, Therefore, the 1st objective of this invention is providing the liquid crystal aligning agent which is excellent in the vertical alignment property and voltage retention characteristic, and has high adhesiveness by a sealing agent. .

It is a second object of the present invention to provide a strong and high quality liquid crystal display device.

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, firstly, a second diamine other than the first diamine represented by the following formula (1) and the first diamine represented by the following formula (2), and tetracarr represented by the following formula (3): It is achieved by the vertically-aligned liquid crystal aligning agent characterized by containing at least any one of the polyamic acid produced | generated by making acid dianhydride react, and the imidation polymer produced | generated by dehydrating and closing this polyamic acid.

In formula, R <^1> is group represented by each of following General formula (1-1)-(1-4).

In the formula, R ² is a divalent organic group.

In the formula, R ³ is a tetravalent organic group containing an aliphatic ring structure,

Moreover, according to this invention, the said objective and advantage of this invention are achieved by the vertically-aligned liquid crystal display element provided with the liquid crystal aligning film formed by the liquid crystal aligning agent mentioned above secondly.

Best Mode for Carrying Out the Invention

[Polyamic acid and imidized polymer]

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail. The polyamic acid used in the present invention is obtained by adding a diamine represented by the formulas (1) and (2) and tetracarboxylic dianhydride represented by the formula (3). In addition, the imidation polymer used by this invention is obtained by dehydrating and ring-closing the said polyamic acid.

[Diamine]

The liquid crystal aligning agent of this invention has the performance excellent in the vertical alignment property, voltage holding property, and sealing agent adhesiveness by using the diamine represented by each of said General formula (1) and General formula (2).

5 to 80 mol% is preferable and, as for the ratio of the 1st diamine compound represented by the said Formula (1) to the sum total of the diamine compound represented by each of said Formula (1) and (2), 5-50 mol% is especially preferable.

As a 2nd diamine compound represented by the said Formula (2), it is p-phenylenediamine, m-phenylenediamine, 4,4'- diamino diphenylmethane, 4,4'- diamino diphenylethane, 4, for example. , 4'-diaminodiphenylsulfide, 4,4'-diaminodiphenylsulfone, 2,2'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diaminobenzanilide, 4 , 4'-diaminodiphenylether, 1,5-diaminonaphthalene, 3,3'-dimethyl-4,4'-diaminobiphenyl, 5-amino-1- (4'-aminophenyl) -1 , 3,3-trimethylindan, 6-amino-1- (4'-aminophenyl) -1,3,3-trimethylindan, 3,4'-diaminodiphenylether, 3,3'-dia Minobenzophenone, 3,4'-diaminobenzophenone, 4,4'-diaminobenzophenone, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2- Bis (4-aminophenyl) hexafluoropropane, 2,2-bis [4- (4-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-a Nophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 9,9-bis (4-aminophenyl) -10-hydroanthracene, 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, 2,2'-bis [4- (4-amino-2-trifluoromethylphenoxy) Phenyl] hexafluoropropane, 4,4'-diamino-2,2'-bis (trifluoromethyl) biphenyl, 4,4'-diamino-2,2'-dimethylbiphenyl, 4,4 Aromatic diamines such as' -bis [(4-amino-2-trifluoromethyl) phenoxy] -octafluorobiphenyl;

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-6-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-dia Mino-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-phenylphenanthtridine, 1,4-diaminopiperazine, Molecules such as 3,6-diaminoacridine, bis (4-aminophenyl) phenylamine and compounds represented by the following formulas (4) and (5) A diamine having the nitrogen atoms other than two primary amino groups and the primary amino group;

(Wherein R ⁵ represents a monovalent organic group having a ring structure containing a nitrogen atom selected from pyridine, pyrimidine, triazine, piperidine and piperazine, and X represents a divalent organic group)

Wherein R ⁶ represents a divalent organic group having a ring structure containing a nitrogen atom selected from pyridine, pyrimidine, triazine, piperidine and piperazine

Mono-substituted phenylenediamines represented by the following Chemical Formula 6, except for the first diamine represented by Chemical Formula 1;

(Wherein R ⁷ represents a divalent organic group selected from -O-, -COO-, -OCO-, -NHCO-, -CONH- and -CO-, R ⁸ represents a steroid skeleton, a trifluoromethyl group, A monovalent organic group having at least one group selected from a trifluoromethoxy group and a fluoro group or an alkyl group having 6 to 30 carbon atoms)

1,1-methacrylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, 4,4-diaminoheptamethylenediamine , 1,4-diaminocyclohexane, isophoronediamine, tetrahydrodicyclopentadienylenediamine, hexahydro-4,7-methanoindenylenedimethylenediamine, tricyclo [6.2.1.0 ^2,7 ] -undecylene Aliphatic and alicyclic diamines such as dimethyldiamine and 4,4'-methylenebis (cyclohexylamine);

Diamino organosiloxane represented by following formula (7) is mentioned. These are used individually or in combination of 2 or more types.

(In formula, R <^9> represents a C1-C12 hydrocarbon group, two or more R <^9> may be same or different, p is an integer of 1-3 and q is an integer of 1-20.)

Among them, p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfide, 1,5-diaminonaphthalene, 2,7-diaminofluorene, 4, 4'-diaminodiphenylether, 9,9-bis (4-aminophenyl) fluorene, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 4,4 '-(p-phenylenediisopropylidene) bisaniline, 4,4'-(m-phenylenediisopropylidene) bisaniline, 1,4-bis (4-aminophenoxy) benzene, 4,4'-bis (4-aminophenoxy) biphenyl, 4,4'-diamino-2,2'-bis (trifluoromethyl) biphenyl, 4, 4'-diamino-2,2'-dimethylbiphenyl, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminoacridine, said Among the compounds represented by the formula (4), the compound represented by the following formula (8), the compound represented by the following formula 9 of the compound represented by the formula (5), and Among the compounds represented by Formula 6, the compounds represented by the following Formulas 10 and 11, 1,4-cyclohexanediamine, 4,4'-methylenebis (cyclohexylamine), and the compounds represented by Formula 7 Preference is given to compounds represented by the formula (12).

Moreover, as a especially preferable thing, p-phenylenediamine, 4,4'- diamino diphenylmethane, 2,2'- dimethyl- 4,4'- diamino biphenyl, 1,3'-bis (4-amino Phenoxy) -2,2-dimethylpropane.

Tetracarboxylic dianhydride

In said Formula (3), R <^3> is a tetravalent organic group containing an aliphatic ring structure. Here, both acid anhydride groups bonded to R ³ are aliphatic. Specific examples of the tetracarboxylic dianhydride represented by the formula (3) include 1,2,3,4-cyclobutanetetracarboxylic dianhydride and 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic Acid 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 dianhydride, 3,5, 6-tricarboxynorbornane-2-acetic acid dianhydride, 2,3,4,5-tetrahydrofurantetracarboxylic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5 (tetra Hydro-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-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 5- (2,5-dioxotetrahydrofural) -3-methyl-3-cyclohexene- 1,2-dicarboxylic dianhydride, bicyclo [2,2,2] -oct-7-ene-2,3,5, And tetracarboxylic dianhydrides such as 6-tetracarboxylic dianhydride and tetracarboxylic dianhydride represented by the following formulas (13), (14), (15) and (16). These are used individually by 1 type or in combination of 2 or more types.

Of these, 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 dianhydride, 5- (2,5-dioxotetrahydrofural) -3-methyl-3-cyclohexene-1,2 Dicarboxylic 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 Water and tetracarboxylic dianhydride represented by the above formula (13) are preferred, among which 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1 , 3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic 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-hexa Particular preference is given to hydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione.

Moreover, as a tetracarboxylic dianhydride used for obtaining the said polyamic acid and the imidation polymer produced by dehydrating and ring-closing this polyamic acid, tetracarboxylic acid other than the tetracarboxylic dianhydride represented by the said General formula (3) A dianhydride can be used together in the range which does not impair the effect by this invention. At this time, 30 mol% or more is preferable, as for the ratio of the tetracarboxylic dianhydride represented by the said Formula (3) to the whole tetracarboxylic dianhydride used for reaction, 50 mol% or more is more preferable, 80 mol% The above is especially preferable.

As another tetracarboxylic dianhydride used together, 3,3 ', 4,4'- benzophenone tetracarboxylic dianhydride, 3,3', 4,4'- diphenylsulfontetracarboxylic acid, for example. Dianhydrides, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3 ', 4,4'-biphenylethertetracarb Acid dianhydrides, 3,3 ', 4,4'-diphenylmethane tetracarboxylic dianhydrides, 3,3', 4,4'-dimethyldiphenylsilanetetracarboxylic dianhydrides, 3,3 ' , 4,4'-tetraphenylsilanetetracarboxylic dianhydride, 1,2,3,4-furtetracarboxylic dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenyl Sulfide dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylsulfone dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylpropane dianhydride, 3 , 3 ', 4,4'-perfluoroisopropylidenediphthalic dianhydride, 3,3', 4,4'-biphenyltetracarboxylic dianhydride , Bis (phthalic acid) phenylphosphineoxide 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 (anhydro trimellitate), propylene glycol-bis (anhydro trimellitate), 1,4-butanediol-bis (anhydro trimellitate), 1,6-hexanediol-bis (anhydro trimellitate), 1,8-octanediol-bis (anhydrotrimelitate), 2,2 -Bis (4-hydroxyphenyl) propane-bis (anhydrotrimelitate), 2,3,4,5-pyridinetetracarboxylic dianhydride, 2,6-bis (3,4-dicarboxyphenyl) Pyridine dianhydride is mentioned. These are used individually by 1 type or in combination of 2 or more types.

Synthesis of Polyamic Acid

The use ratio of the tetracarboxylic dianhydride and diamine compound used for the synthesis reaction of the polyamic acid of this invention becomes 0.2-2 equivalent of the acid anhydride group of tetracarboxylic dianhydride with respect to 1 equivalent of the amino group contained in a diamine compound. A ratio is preferable, More preferably, it is a ratio which becomes 0.3 to 1.2 equivalent.

The synthesis reaction of the polyamic acid is preferably carried out in an organic solvent under a temperature condition of -20 to 150 ° C, more preferably 0 to 100 ° C. The organic solvent is not particularly limited as long as it can dissolve the polyamic acid synthesized. For example, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethyl Aprotic polar solvents such as sulfoxide, γ-butyrolactone, tetramethylurea and hexamethylphosphortriamide; Phenol solvents, such as m-cresol, xylenol, a phenol, and a halogenated phenol, can be illustrated. The amount of the organic solvent (a) is preferably an amount such that the total amount (b) of the tetracarboxylic dianhydride and the diamine compound becomes 0.1 to 30% by weight based on the total amount (a + b) of the reaction solution.

In the organic solvent, alcohol, ketones, esters, ethers, halogenated hydrocarbons and hydrocarbons, which are poor solvents of polyamic acid, may be used in combination without causing precipitation of the resulting polyamic acid. Specific examples of such poor solvents include methyl alcohol, ethyl alcohol, isopropyl alcohol, cyclohexanol, ethylene glycol, propylene glycol, 1,4-butanediol, triethylene glycol, diacetone alcohol, ethylene glycol monomethyl ether, Ethyl lactate, butyl lactate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl acetate, ethyl acetate, butyl acetate, methyl methoxy propionate, ethyl ethoxy propionate, propylene carbonate, oxalic acid Diethyl, diethyl malonate, diethyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n-propyl ether, ethylene glycol-i-propyl ether, ethylene glycol monobutyl ether (butyl cellosolve), Ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol Recall 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 and the like. These poor solvents can be used individually or in combination of 2 or more types.

The reaction solution which melt | dissolves a polyamic acid as mentioned above is obtained. In addition, a polyamic acid can be obtained by pouring the reaction solution into a large amount of poor solvent to obtain a precipitate, and then drying the precipitate under reduced pressure. Moreover, a polyamic acid can be refine | purified by performing the process which dissolves this polyamic acid again in an organic solvent and then precipitates with a poor solvent once or several times.

<Imidated Polymer>

The imidation polymer of this invention can be manufactured by dehydrating and ring-closing the said polyamic acid. The dehydration ring closure of the polyamic acid may be carried out by heating (I) the polyamic acid, or (II) dissolving the polyamic acid in an organic solvent, adding a dehydrating agent and a dehydration ring closure catalyst to the solution, and heating it as necessary. Is done by.

Preferably the reaction temperature in the method of heating the polyamic acid of said (I) is 50-200 degreeC, More preferably, it is 60-170 degreeC. When reaction temperature is less than 50 degreeC, dehydration ring-closure reaction does not fully advance, but when reaction temperature exceeds 200 degreeC, the molecular weight of the imidation polymer obtained may fall.

On the other hand, in the method of adding a dehydrating agent and a dehydration ring-closure catalyst to the solution of the polyamic acid of said (II), acid anhydrides, such as acetic anhydride, propionic anhydride, and trifluoroacetic anhydride, can be used as a dehydrating agent, for example. It is preferable that the usage-amount of a dehydrating agent shall be 0.01-20 mol with respect to 1 mol of repeating units of a polyamic acid. As the dehydration ring closure catalyst, tertiary amines such as pyridine, collidine, lutidine and triethylamine can be used, for example. However, it is not limited to this. It is preferable that the usage-amount of a dehydration ring-closure catalyst shall be 0.01-10 mol with respect to 1 mol of dehydrating agents used. Moreover, as an organic solvent used for dehydration ring-closure reaction, the same thing as the organic solvent illustrated by what is used for the synthesis | combination of a polyamic acid is mentioned. The reaction temperature of the dehydration ring-closure reaction is preferably 0 to 180 ° C, more preferably 10 to 150 ° C. Moreover, the imidation polymer can be refine | purified by performing the same operation as the purification method of a polyamic acid with respect to the reaction solution obtained in this way.

The preferable imidation ratio in the imidation polymer in the case of constituting the liquid crystal aligning agent of this invention is 1 to 100%, More preferably, it is 10 to 98%. Here, "imidation ratio" shows the ratio of the number of repeating units which form an imide ring with respect to the total number of repeating units in a polymer in%. At this time, a part of the imide ring may be an isoimide ring. The imidation ratio can be controlled by adjusting the reaction conditions of the dehydration ring closure reaction.

<Polymer of Terminal Modified Type>

The polyamic acid and the imidation polymer which comprise the liquid crystal aligning agent of this invention may be a terminal modified form in which molecular weight was adjusted. By using this terminal modified polymer, the effect of this invention can be improved, and the coating characteristic of a liquid crystal aligning agent can be improved. Such terminal-modified ones can be synthesized by adding an acid anhydride, a monoamine compound, a monoisocyanate compound and the like to the reaction system when synthesizing the polyamic acid. Here, as an acid anhydride, maleic anhydride, a phthalic anhydride, itaconic anhydride, n-decyl succinic anhydride, n-dodecyl succinic anhydride, n- tetradecyl succinic anhydride, n-hexadecyl succinic anhydride etc. are mentioned, for example. Can be. As the monoamine compound, for example, aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine , n-undecylamine, n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecylamine, n-octadecylamine, n -Eicosylamine, etc. are mentioned. Moreover, as a monoisocyanate compound, phenyl isocyanate, naphthyl isocyanate, etc. are mentioned, for example.

In addition, the liquid crystal aligning agent of this invention can be obtained also by the method of copolymerizing the polyimide block and polyamic-acid block disclosed by Unexamined-Japanese-Patent No. 2002-204250, for example. In this case, the preferable imidation ratio in the polyimide block is 10 to 100%, more preferably 30 to 98%.

Logarithmic viscosity of the polymer

The value of the logarithmic viscosity ((eta) 1n) of the polyamic acid and imidation polymer which comprise the liquid crystal aligning agent of this invention becomes like this. Preferably it is 0.05-10 dl / g, More preferably, it is 0.1-5 dl / g.

The value of the logarithmic viscosity (η1n) in the present invention uses N-methyl-2-pyrrolidone as a solvent, and measures the viscosity at 30 ° C with respect to a solution having a concentration of 0.5 g / 100 milliliter, Obtained by

<Imidation Rate of Polymer>

The polyimide was dried under reduced pressure at room temperature, dissolved in deuterated dimethyl sulfoxide, and tetramethylsilane was measured at room temperature using ¹ H-NMR as a reference material, and obtained by the following formula.

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

In formula, A <^1> is the peak area (10 ppm) derived from the proton of a NH group, A <^2> is the peak area derived from another proton, and (alpha) is one proton of the NH group in the precursor (polyamic acid) of a polymer. The ratio of the number of other protons to.

<Liquid crystal aligning agent>

The polyamic acid and imidation polymer which comprise the liquid crystal aligning agent of this invention, Preferably, it melts and contains in an organic solvent, and is comprised.

The temperature at the time of manufacturing the liquid crystal aligning agent of this invention becomes like this. Preferably it is 0 degreeC-200 degreeC, More preferably, it is 20 degreeC-60 degreeC.

As an organic solvent which comprises the liquid crystal aligning agent of this invention, the solvent illustrated as what is used for the synthesis reaction of polyamic acid is mentioned. Among them, a solvent having a boiling point of 160 ° C. or higher is preferable from the viewpoint of printability, and for example, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, dimethyl sulfoxide, γ-butyrolactone, tetramethylurea, Hexamethylphosphortriamide, m-cresol, xylenol, phenol, cyclohexanol, ethylene glycol, propylene glycol, 1,4-butanediol, triethylene glycol, diacetone alcohol, butyl lactate, butyl acetate, ethyl ethoxy Propionate, propylene carbonate, diethyl oxalate, diethyl malonate, ethylene glycol monobutyl ether, 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, 1,4-dichlorobutane, o-dichlorobenzene, and the like. The N- methyl-γ- lactone -butyrolactone, diacetone alcohol, ethylene glycol monobutyl ether, propylene carbonate, diethylene glycol diethyl ether is particularly preferred from.

Although solid content concentration in the liquid crystal aligning agent of this invention is selected in consideration of viscosity, volatility, etc., Preferably it is the range of 1 to 10 weight%. That is, although the liquid crystal aligning agent of this invention is apply | coated to the surface of a board | substrate, and the coating film used as a liquid crystal aligning film is formed, when solid content concentration is less than 1 weight%, the film thickness of this coating film becomes small and a favorable liquid crystal aligning film cannot be obtained, and solid content concentration is carried out. When exceeds 10 weight%, the film thickness of a coating film becomes excessive and a favorable liquid crystal aligning film cannot be obtained, the viscosity of a liquid crystal aligning agent will increase, and coating property will fall.

The liquid crystal aligning agent of this invention may contain a functional silane containing compound or an epoxy group containing compound from a viewpoint of improving the adhesiveness to the surface of a board | substrate. As such a functional silane containing compound, 3-aminopropyl trimethoxysilane, 3-aminopropyl triethoxysilane, 2-aminopropyl trimethoxysilane, 2-aminopropyl triethoxysilane, N- ( 2-aminoethyl) -3-aminopropyl trimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyl dimethoxysilane, 3-ureidopropyl trimethoxysilane, 3-ureidopropyl trie Methoxysilane, N-ethoxycarbonyl-3-aminopropyl trimethoxysilane, N-ethoxycarbonyl-3-aminopropyl triethoxysilane, N-triethoxysilylpropyl triethylenetriamine, N-tri Methoxysilylpropyl triethylenetriamine, 10-trimethoxysilyl-1,4,7-triadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl- 3,6-diazanyl acetate, 9-triethoxysilyl-3,6-diazanyl acetate, N-benzyl-3-aminopropyl trimethoxy Silane, N-benzyl-3-aminopropyl triethoxysilane, N-phenyl-3-aminopropyl trimethoxysilane, N-phenyl-3-aminopropyl triethoxysilane, N-bis (oxyethylene) -3 -Aminopropyl trimethoxysilane, N-bis (oxyethylene) -3-aminopropyl triethoxysilane, etc. are mentioned.

As the epoxy group-containing compound, for example, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol digly Cydyl 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-digly Cydylaminomethyl) cyclohexane, N, N, N ', N'- tetraglycidyl-4,4'- diaminodiphenylmethane, etc. are mentioned as a preferable thing. The compounding ratio of these functional silane containing compounds and epoxy group containing compounds becomes like this. Preferably it is 60 weight part or less, More preferably, it is 50 weight part or less with respect to 100 weight part of polymers.

<Liquid crystal display element>

The liquid crystal display element of this invention can be manufactured by the following method, for example.

(1) The liquid crystal aligning agent of this invention is apply | coated to one side of the board | substrate with which the patterned transparent conductive film is provided by methods, such as a roll coating method, a spinner method, the printing method, the inkjet method, and then a coating surface is then applied. The coating film is formed by heating. Here, as a board | substrate, For example, glass, such as a float glass and a soda glass; Transparent substrates containing plastics such as polyethylene terephthalate, polybutylene terephthalate, polyether sulfone, polycarbonate and the like can be used. Examples of the transparent conductive film provided on one side of the substrate include an NESA film containing tin oxide (SnO ₂ ) (registered trademark of PPG, USA), an ITO film containing indium tin oxide (In ₂ O ₃ -SnO ₂ ), and the like. Can be used. The photo-etching method and the method of using a mask beforehand are used for patterning these transparent conductive films. Metals, such as Al and Ag, or the alloy containing these metals etc. can be used for a reflecting electrode. As long as it has sufficient reflectance, it is not limited to this. In the case of coating the liquid crystal aligning agent, a functional silane-containing compound, a functional titanium-containing compound, or the like may be applied to the surface of the substrate in advance in order to further improve the adhesion between the substrate surface and the transparent conductive film or the reflective electrode and the coating film. have. The heating temperature after liquid crystal aligning agent application becomes like this. Preferably it is 80-300 degreeC, More preferably, it is 120-250 degreeC. Although the liquid crystal aligning agent of this invention containing a polyamic acid forms the coating film used as an oriented film by removing an organic solvent after application | coating, it can also be made into the more imidized coating film by advancing dehydration ring closure by further heating. The film thickness of the coating film formed becomes like this. Preferably it is 0.001-1 micrometer, More preferably, it is 0.005-0.5 micrometer.

(2) As described in Japanese Unexamined Patent Publication No. 2002-327058, the formed coating film surface is formed on the substrate by using a photosensitive resin, and a vertical liquid crystal alignment film is formed thereon.

(3) Two board | substrates with a perpendicular | vertical liquid crystal aligning film were manufactured as mentioned above, two board | substrates were opposingly arranged through a gap (cell spacing), the two board | substrate peripheral parts were bonded together using a sealing agent, and the board | substrate surface and sealing The liquid crystal is injected and filled into the cell gap partitioned by agent, and the injection hole is sealed to form a liquid crystal cell. Moreover, a liquid crystal display element can be obtained by arrange | positioning a polarizing plate in the outer surface of a liquid crystal cell, ie, the transparent substrate side which comprises a liquid crystal cell.

Here, as a sealing agent, the epoxy resin etc. which contain the hardening agent and aluminum oxide sphere as a spacer can be used, for example.

Examples of the liquid crystal include nematic liquid crystals and smectic liquid crystals. Especially, a nematic liquid crystal is preferable, for example, a Schiff base type liquid crystal, a subfamily clock liquid crystal, a biphenyl type liquid crystal, a phenylcyclohexane type liquid crystal, an ester type liquid crystal, a tert-phenyl type liquid crystal, a biphenyl cyclohexane type liquid crystal, a flute A midine liquid crystal, a dioxane liquid crystal, a bicyclooctane type liquid crystal, a cuban type liquid crystal, etc. can be used. Moreover, it sells to these liquid crystals as cholesteric liquid crystals, such as cholestyl chloride, cholesteryl nonaate, cholesteryl carbonate, and brand name "C-15" "CB-15" (made by Merck), for example. It is also possible to add and use a chiral agent. Ferroelectric liquid crystals such as p-decyloxybenzylidene-p-amino-2-methylbutylcinnamate can also be used.

Moreover, as a polarizing plate bonded to the outer surface of a liquid crystal cell, the polarizing plate which consists of a polarizing plate called H film which absorbed iodine, and extended | stretched polyvinyl alcohol between the cellulose-acetic acid protective film, or the polarizing plate which consists of H film itself is mentioned.

<Example>

Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not restrict | limited to these Examples. Sealant adhesiveness, vertical orientation, and voltage retention in the Examples and Comparative Examples were evaluated by the following method.

[Vertical orientation]

The abnormal domain when the voltage was turned on and off under cross nicol was observed in the liquid crystal display element, and the absence of the abnormal domain was "good" and the "bad" was present.

[Voltage holding characteristic]

After applying a voltage of 5 V to the liquid crystal display element at an application time of 60 microseconds and a span of 167 milliseconds, the voltage retention after 167 milliseconds from the release of the application was measured. The measurement apparatus used VHR-1 by Toyo Technica.

[Seal Adhesive Adhesive]

After apply | coating the liquid crystal aligning agent of this invention to the glass substrate with a transparent electrode in which the ITO film | membrane is formed in the film thickness of 200 nm using a spin coater, and forming a liquid crystal aligning film by baking, it is the same type using an epoxy resin sealing agent. Two substrates with a liquid crystal aligning film were bonded together, and the adhesive evaluation of the sealing agent was performed using the tensile tester.

Printability Test

The liquid crystal aligning agent of this invention was used for the glass substrate with a transparent electrode in which the ITO film | membrane of 200 nm in thickness and 20 micrometers in width is formed in stripe shape at intervals of 100 micrometers using a liquid crystal aligning film printer (made by Nippon Shashin Insatsu Co., Ltd.). After apply | coating to a transparent electrode surface and forming a liquid crystal aligning film by baking, the case where there is no application | coating nonuniformity when the peripheral part and center part of this liquid crystal aligning film are observed by the microscope of 20 times magnification, and there is no application | coating nonuniformity " Defective ".

Synthesis Example 1

224 g (1.0 mol) of 2,3,5-tricarboxycyclopentylacetic dianhydride as tetracarboxylic dianhydride, 99 g (0.8 mol) of p-phenylenediamine as a diamine compound, and R ¹ in Formula ¹ 87 g (0.2 mol) of the diamine compound represented by (1-1) was dissolved in 4,500 g of N-methyl-2-pyrrolidone and reacted at 60 ° C for 4 hours. The reaction solution was then poured into excess methyl alcohol to precipitate the reaction product. Thereafter, the resultant was washed with methyl alcohol and dried at 40 ° C. for 24 hours under reduced pressure to obtain 370 g of polyamic acid having a logarithmic viscosity of 0.55 dl / g. 30 g of the obtained polyamic acid was dissolved in 570 g of N-methyl-2-pyrrolidone, and 5.8 g of pyridine and 7.5 g of acetic anhydride (1 equivalent of the repeating unit of polyamic acid in both pyridine and acetic anhydride) were added at 110 캜. It was dehydrated and closed for 4 hours, precipitated, washed and decompressed in the same manner as above to obtain 18 g of an imidized polymer (this is referred to as "P-1") having a logarithmic viscosity of 0.51 dl / g and an imidation ratio of 51%.

<Synthesis Examples 2-3 and Comparative Synthesis Examples 1-3>

Except having changed the tetracarboxylic dianhydride and the diamine compound into what was shown in following Table 1, the polymer of the logarithmic viscosity and imidation ratio shown in Table 1 similarly to the synthesis example 1 (these were "P-2"-"P -7 "). In addition, "P-4" and "P-7" are not imidated with polyamic acid.

Acid anhydride and diamine compound in Table 1 are as follows.

Acid Anhydride A: 2,3,5-tricarboxycyclopentylacetic dianhydride

Acid Anhydride B: pyromellitic dianhydride

Diamine A: Diamine compound in which R <1> in the said General formula ( ¹ ) is represented by General formula (1-1)

Diamine B: the diamine compound in which R ¹ in Formula ¹ is represented by Formula (1-2)

Diamine C: p-phenylenediamine

Diamine D: 4,4'-diaminodiphenylmethane

Diamine E: cholestanyl-3,5-diaminobenzoate

Diamine F: 2,2-bis [4- (4-aminophenoxy) phenyl] propane

<Example 1>

Vertical orientation, voltage retention and sealant adhesiveness in the examples were evaluated by the following method.

(Vertical orientation)

The imidated polymer (P-1) obtained by the synthesis example 1 was dissolved in N-methyl- 2-pyrrolidone / ethylene glycol monobutyl ether mixed solvent (weight ratio 50/50), and N, N, N ', N' Tetraglycidyl-4,4'-diaminodiphenylmethane was added 20% by weight with respect to P-1, and the mixture was sufficiently stirred to give a solution having a solid content of 3.5% by weight. After filtration by using, a spinner was applied onto a transparent conductive film including an ITO film provided on one side of the glass substrate, pre-dried at 80 ° C. for 1 minute on a hot plate, and then 1 hour at 200 ° C. in a clean oven. By drying, a transparent electrode substrate having a liquid crystal alignment film having a dry film thickness of 50 nm was prepared. Subsequently, an epoxy resin adhesive containing aluminum oxide spheres having a diameter of 5.5 μm was applied to each outer edge portion of the pair of transparent electrode / transparent electrode substrates having the liquid crystal alignment film of the liquid crystal alignment film coating substrate, and then overlapped so that the liquid crystal alignment film surfaces faced each other. And the adhesive was cured. Subsequently, after filling a negative liquid crystal (MLC-2038 by Merck Co., Ltd.) between board | substrates from a liquid crystal injection hole, the liquid crystal injection hole was sealed with the acryl-type photocuring adhesive agent, and the liquid crystal display element was manufactured. The abnormal domain at the time of turning on / off the voltage under the cross nicol to the manufactured liquid crystal display element was observed, and the absence of the abnormal domain was said to be "good" and the "bad". The results are shown in Table 2 below.

(Voltage retention)

After applying the voltage of 5V to the manufactured liquid crystal display element by 60 microseconds application time and the span of 167 milliseconds, the voltage retention after 167 milliseconds after application | release cancellation was measured. The measurement apparatus used VHR-1 by Toyo Technica. The results are shown in Table 2.

(Seal Adhesive)

A transparent electrode substrate having a liquid crystal aligning film of P-1 was produced in the same manner as the method for producing a liquid crystal display element described above. Subsequently, after applying a pair of transparent electrode / transparent electrode board | substrate to each center part which has a liquid crystal aligning film of the said liquid crystal aligning film coating board | substrate, the epoxy resin adhesive containing the aluminum oxide sphere of 5.5 micrometers in diameter, so that a liquid crystal aligning film surface may face. Overlaid and pressed to cure the adhesive. The adhesive evaluation of the sealing agent was performed using the tensile tester. When it applied the pressure of 2 Kgf, it was "good" and the thing which peeled was "defect". The results are shown in Table 2.

(Printability test)

The imidated polymer (P-1) obtained by the synthesis example 1 was dissolved in N-methyl- 2-pyrrolidone / ethylene glycol monobutyl ether mixed solvent (weight ratio 50/50), and N, N, N ', N' Tetraglycidyl-4,4'-diaminodiphenylmethane was added 20% by weight with respect to P-1, and the mixture was sufficiently stirred to give a solution having a solid content of 3.5% by weight. It filtered using the liquid crystal aligning agent of this invention. The liquid crystal aligning agent was applied onto a transparent conductive film containing an ITO film provided on one side of a glass substrate using a liquid crystal alignment film printer (manufactured by Nippon Shashin Insatsu Co., Ltd.), and preliminarily dried at 80 ° C. on a hot plate for 1 minute. Then, the liquid crystal aligning film of 50 nm of dry film thickness was formed by drying at 200 degreeC for 1 hour in a clean oven. Application | coating nonuniformity was not observed in this liquid crystal aligning film, Therefore, the printability of the liquid crystal aligning agent manufactured in Example 1 was determined to be "good."

<Examples 2 to 3 and Comparative Examples 1 to 3>

About the polymer "P-2"-"P-7", the liquid crystal aligning agent was produced like Example 1 except having used the solvent composition and additive amount shown in Table 2, and it carried out similarly to Example 1, and has a vertical alignment property. , Voltage retention, sealant adhesiveness, and printability were evaluated. The results are shown in Table 2.

The notation in Table 2 is as follows.

Additives: N, N, N ', N'-tetraglycidyl-4,4'-diaminodiphenylmethane

BL: γ-butyrolactone

NMP: N-methyl-2-pyrrolidone

BC: ethylene glycol monobutyl ether

According to the liquid crystal aligning agent of this invention, the liquid crystal aligning film excellent in the vertical alignment property, voltage retention, and sealing agent adhesiveness can be obtained.

Claims (3)

A polyamic acid and this polyamic acid produced by reacting a first diamine represented by the following formula (1) with a second diamine other than the first diamine represented by the following formula (2), and tetracarboxylic dianhydride represented by the following formula (3) At least any one of the imidation polymer produced | generated by dehydration ring closure is contained, The vertically-aligned liquid crystal aligning agent characterized by the above-mentioned. <Formula 1>

(In formula, R <^1> is group represented by each of following General formula (1-1)-(1-4).

) <Formula 2>

(In formula, R <^2> is a divalent organic group.) <Formula 3>

(Wherein R ³ is a tetravalent organic group containing an aliphatic ring structure.) The tetracarboxylic dianhydride represented by the formula (3) is 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4- Cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo -3-furanyl) -naphtho [1,2-c] furan-1,3-dione or 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2 , 5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione. The liquid crystal aligning film formed from the liquid crystal aligning agent of Claim 1 is provided, The vertical alignment liquid crystal display element characterized by the above-mentioned.