JP3050478B2 - Liquid crystal alignment film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal alignment film having a portion where the alignment of liquid crystal molecules is partially different.

[0002]

2. Description of the Related Art In general, a liquid crystal alignment film is used for a liquid crystal display device, and aligns liquid crystal molecules in a certain direction.
That is, it is provided because it needs to be oriented.
2. Description of the Related Art Liquid crystal display devices have been conventionally used for displays such as watches, calculators, computers, and word processors. As a basic structure of a liquid crystal display element, it is common that two substrates having an alignment film provided on a transparent electrode are arranged with the alignment film inside, and a liquid crystal is sealed between them.

As such a liquid crystal display element, a display in a twisted nematic (TN) mode in which a nematic liquid crystal has a twisted structure or a super twisted nematic (STN) mode is known. As the driving of the liquid crystal display element, there is known a matrix display in which electrodes are formed in a display pattern such as a stripe shape or a grid shape on a substrate, and a device using a thin film transistor (TFT). Something comparable to a normal CRT has been realized. However, such a liquid crystal display element has a disadvantage that the viewing angle is narrow.

Several methods have been proposed to improve the viewing angle. For example, page 94 of the latest 94 LCD Technology discloses a two-rubbing method in which an alignment film is rubbed, patterned with a resist, and then rubbed in the opposite direction, or a method of forming the alignment film into a two-layer structure. However, these methods involve a patterning step using a resist, so that there are problems such as an increase in production cost and a problem that the conventional alignment film material has poor solvent resistance.

[0005]

The present invention solves the above-mentioned problems of the prior art and relates to a liquid crystal alignment film having a portion in which the surface of the alignment film is irradiated with light to change the pretilt angle of liquid crystal molecules. .

[0006]

Means for Solving the Problems The liquid crystal alignment film of the present invention is represented by the following chemical formula (I).

[0007]

Embedded image [Wherein, in the general formula (I), A is a tetravalent residue of tetracarboxylic dianhydride except for a cyclobutane ring , R is a divalent organic group, and A and / or R have a siloxane structure. Including. The surface of the polyimide containing the structural unit represented by the formula (1) is irradiated with light in the range of 0.3 to 10 J / cm ² to have portions having different orientations of liquid crystal molecules.

The above-mentioned polyimide is represented by the following general formula (IV):

Embedded image [However, in the general formula (IV), B and R 'represent a tetravalent residue of a tetracarboxylic dianhydride other than A and R shown in the general formula (I), or a divalent organic group] It may include the structural unit represented.

The polyimide preferably contains 0.1 to 100 mol%, more preferably 1 to 100 mol%, of the structural unit represented by the above general formula (I). In the above, the general formula (IV) is adjusted so that the total is 100 mol%.
May be appropriately contained.
Polyimide containing too few structural units represented by the general formula (I) has a small change in pretilt angle when irradiated with light and cannot be divided well. Tends to decrease.

The liquid crystal alignment film is made of ITO (Indium Tin Oxi).
The substrate is formed on an electrode substrate such as a glass plate provided with a transparent electrode such as de), and a pair of the substrates is opposed to each other, and a liquid crystal is sandwiched between the electrode substrates to form a liquid crystal sandwiching substrate. In this case, the liquid crystal alignment film formed on one of the electrode substrates of the liquid crystal holding substrate may have no change in the pretilt angle.

Further, a liquid crystal display element having a liquid crystal holding substrate can be obtained by a known method using the above liquid crystal holding substrate.

The liquid crystal alignment film can be manufactured using a liquid crystal alignment film material containing a polyamic acid which is a precursor of polyimide. This polyamic acid is represented by
[General formula (II)]

[0013]

Embedded image [However, in the general formula (II), A and R are the same as those in the general formula (I)].

The polyamic acid has a structure represented by the following general formula (V) in addition to the structural unit represented by the general formula (II):

Embedded image [However, in the general formula (V), B and R 'represent the general formula (IV)
The same applies to the above.].

The polyamic acid preferably contains 0.1 to 100 mol%, more preferably 1 to 100 mol%, of the structural unit represented by the general formula (II). In the above, the general formula (V) is adjusted so that the total is 100 mol%.
May be appropriately contained.

The liquid crystal alignment film can be manufactured using a liquid crystal alignment film material containing a polyimide resin described below. The polyimide resin is a general term for the above-mentioned polyimide and its precursor. Examples of the polyimide precursor include the above-mentioned polyamic acid and a partially imidized polyamic acid.

The above polyimide resin is represented by the following general formula (III) or 9 (general formula (IV)):

[0018]

Embedded image [However, in the general formulas (III) and (VI), A and R are the same as those in the general formula (I). ]

Embedded image H ₂ N—R—NH _{2 ...} (VI)
By reacting a tetracarboxylic dianhydride and a diamine compound represented by the formula:

In the production of the above-mentioned polyimide resin, the content of the tetracarboxylic dianhydride or diamine having a siloxane structure is preferably 0.1 to 100 mol%, particularly preferably 1 to 100 mol%. In the above,
Tetracarboxylic dianhydride diamine containing no siloxane structure can be appropriately contained so that the total amount is 100 mol%.

Examples of the tetracarboxylic dianhydride having a siloxane structure include 1,3-bis (3,4-dioxycarbonyl) -1,1,3,3-
Tetramethyldisiloxane dianhydride, 1,3-bis (3,4-dicarboxyphenyl) -1,1,3,3-tetraphenyldisiloxane dianhydride, 1,3-bis (3,4-diphenyl) (Carboxyphenyl) -1,3-dimethyl-1,3-diphenyldisiloxane dianhydride, 1,5-bis (3,4-dioxycarbonyl) -1,1,3,3,5,5-hexamethyl Trisiloxane dianhydride, 1,7-bis (3,4-dioxyoxyphenyl) -1,1,3,3,5,5,7,7-octamethyltetrasiloxane dianhydride, 1,3-bis (3,4-doxyphenyl) -1,
1,3,3-tetraisopropyldisiloxane dianhydride, 1,3
-Bis (3,4-dicarboxyphenyl) -1,1,3,3-tetramethoxydisiloxane dianhydride and the like, and as a diamine having a siloxane structure, 1,3-bis (3-aminopropyl ) -1,1,1-tetraphenyldisiloxane, 1,
There are 3-bis (3-aminopropyl) -1,1,1-tetramethyldisiloxane, 1,3-bis (4-aminobutyl) -1,1,1-tetramethyldisiloxane and the like. More than one type may be used in combination.

[0021] Examples of the general formula (III) acid dianhydride other than the tetracarboxylic acid dianhydride represented by, butane-1,2,3,4-tetracarboxylic dianhydride, shea Kuropentan 1,2 2,3,4-tetracarboxylic dianhydride, cyclohexane-1,2,4,5-tetracarboxylic dianhydride, 3,4,3 ', 4'-bicyclohexyltetracarboxylic dianhydride, bis [ Bicyclo (2,2,1) hepta-2,3-dicarboxylic anhydride] sulfone, 1,3-di (3,4-dicarboxycyclohexyl) cyclohexanol dianhydride, bicyclo (2,2,1) hepta -2,3,5,6-tetracarboxylic dianhydride, bicyclo (2,2,2) oct-7-ene-2,3
5,6-tetracarboxylic dianhydride, decahydronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 4,8-dimethyl-1,2,3,5,6,7-hexahydro Naphthalene-1,2,5,6-tetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride.

Ethylene glycol bis (trimellitic anhydride), 1,3-propanediol bis (trimellitic anhydride), 1,4-butanediol bis (trimellitic anhydride), 1,5-pentanediol Bis (trimellitic anhydride), 1,6-hexanediol bis (trimellitic anhydride), 1,8-octanediol bis (trimellitic anhydride), 1,10-decanediol bis (trimellitic acid) Anhydride), 1,16-hexadecanediol bis (trimellitic anhydride) pyromellitic anhydride, 3,3 ′, 4,4′-diphenyltetracarboxylic dianhydride, 1,2,5,6 -Naphthalenetetracarboxylic dianhydride, 2,3,6,7,-
Naphthalenetetracarboxylic dianhydride, 2,2 ', 3
3'-diphenyltetracarboxylic dianhydride, 2,2-
Bis (3,4, -dicarboxyphenyl) propane dianhydride, bis (3,4-dicarboxyphenyl) sulfone dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, bis (3 , 4-Dicarboxyphenyl) ether dianhydride, naphthalene-1,2,4,5-tetracarboxylic dianhydride, naphthalene-1,4,5,8-tetracarboxylic dianhydride, 2,6- Dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 2,7
Dichloronaphthalene-1,4,5,8, tetracarboxylic dianhydride, 2,3,6,7-tetrachloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, phenanthrene-1 , 8,9,10-Tetracarboxylic dianhydride, 2,2-bis (2,3-dicarboxyphenyl)
Propane dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,1-bis (3,4-
Dicarboxyphenyl) ethane dianhydride, bis (2,3
-Dicarboxyphenyl) methane dianhydride, bis (3,
4-dicarboxyphenyl) methane dianhydride, bis (3,4-dicarboxyphenyl) sulfone dianhydride,

Benzene-1,2,3,4-tetracarboxylic dianhydride, 3,4,3 ', 4'-benzophenonetetracarboxylic dianhydride, 2,3,2', 3-benzophenonetetracarboxylic Acid dianhydride, 2,3,3 ', 4'
-Benzonephenone tetracarboxylic dianhydride, pyrazine-2,3,5,6-tetracarboxylic dianhydride, thiophene-2,3,4,5-tetracarboxylic dianhydride,
Ethylene tetracarboxylic dianhydride, 2,3,3 ',
4′-biphenyltetracarboxylic dianhydride, 3,4
3 ′, 4′-biphenyltetracarboxylic dianhydride,
2,3,2 ', 3'-biphenyltetracarboxylic dianhydride, bis (3,4-dicarboxyphenyl) dimethylsilane dianhydride, bis (3,4-dicarboxyphenyl) methylphenylsilane dianhydride , Bis (3,4-dicarboxyphenyl) diphenylsilane dianhydride, bis (2,3-dicarboxyphenyl) dimethylsilane dianhydride, 1,4-bis (3,4-dicarboxyphenyldimethylsilyl) benzene Dianhydride, p-phenylbis (trimellitic acid monoester acid anhydride), 4,4'-bis (3,4-dicarboxyphenoxy) diphenylsulfide dianhydride, 2,2-bis (2 3-dicarboxyphenyl) hexafluoropropane dianhydride, 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride, 2,2-bi [4- (3,4-dicarboxyphenoxy) phenyl] hexafluoropropane dianhydride, 1,4-bis (2-hydroxyhexafluoropropyl) benzenebistrimellitic dianhydride,
1,3-bis (2-hydroxyhexafluoropropyl) benzenebistrimellitic dianhydride,

(Trifluoromethyl) pyromellitic dianhydride, bis (trifluoromethyl) pyromellitic dianhydride, 5,5'-bis (trifluoromethyl) -3,
3 ', 4,4'-biphenyltetracarboxylic dianhydride, 2,2', 5,5'-tetrakis (trifluoromethyl) -3,3 ', 4,4'-biphenyltetracarboxylic dianhydride , 5,5'-bis (trifluoromethyl)-
3,3 ', 4,4'-diphenylethertetracarboxylic dianhydride, 5,5'-bis (trifluoromethyl)
-3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride, bis {(trifluoromethyl) dicarboxyphenoxy} benzene dianhydride, bis {(trifluoromethyl) dicarboxyphenoxy} biphenyl dianhydride , Bis {(trifluoromethyl) dicarboxyphenoxy} (trifluoromethyl) benzene dianhydride, bis {(trifluoromethyl) dicarboxyphenoxy} bis (trifluoromethyl) biphenyl dianhydride, bis {(trifluoromethyl) ) Dicarboxyphenoxy diphenylether dianhydride, bis (dicarboxyphenoxy) (trifluoromethyl) benzene dianhydride, bis
(Dicarboxyphenoxy) bis (trifluoromethyl) benzene dianhydride, bis (dicarboxyphenoxy) tetrakis (trifluoromethyl) benzene dianhydride, bis (dicarboxyphenoxy) bis (trifluoromethyl) biphenyl dianhydride, Bis (dicarboxyphenoxy) tetrakis (trifluoromethyl) biphenyl dianhydride; These may be used in combination of two or more.

Examples of the diamine compound other than the diamine (VI) include 4- (4-aminophenyl) -3-aminobenzoic acid, 2,2-bis (4-aminophenyl) propane, 2,6-diaminopyridine, Bis (4-aminophenyl) diethylsilane, bis- (4-aminophenyl)
Diphenylsilane, bis- (4-aminophenyl) ethylphosphine oxide, bis- (4-aminophenyl) -N-butylamine, bis- (4-aminophenyl) -N-methylamine, N- (3-aminophenyl)
-4-aminobenzamide, 3,3'-diaminodiphenylmethane, 3,3'-diaminodiphenylether,
3,3'-diaminodiphenylsulfone, 3,3'-diaminodiphenylpropane, 3,3'-diaminodiphenylsulfide, 2,3,5,6-tetramethyl-p-
Phenylenediamine p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine m-phenylenediamine, m-xylenediamine, 2,
4-diaminotoluene, 2,6-diaminotoluene,
4,4′-diaminodiphenylpropane, 4,4′-diaminodiphenylmethane, 3,3′-diaminobenzophenone, 4,4′-diaminodiphenyl sulfide,
4,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 1,5-diaminonaphthalene, 2,6-
Diaminenaphthalene 2,2-bis (4- (aminophenoxyphenyl)) propane

2,4-bis (β-amino-t-butyl)
Toluene, bis (p-β-amino-t-butyl-phenyl) ether, bis (p-β-methyl-γ-amino-pentyl) benzene, bis-p- (1,1-dimethyl-5)
-Aminopentyl) benzene, 2,2-bis (4-aminophenyl) hexafluoropropane, 2,2-bis {4- (2-aminophenoxy) phenyl} hexafluoropropane, 2,2-bis {4- ( 3-aminophenoxy) phenyl {hexafluoropropane, 2,2-bis} 4-
(4-aminophenoxy) phenyl} hexafluoropropane, 2,2-bis (3-carbamoyl-4-aminophenyl) hexafluoropropane, 2,2-bis {4- (3
-Carbamoyl-4-aminophenoxy) phenyl} hexafluoropropane, 2,2-bis (3-sulfamoyl-4-aminophenyl) hexafluoropropane, 2,
2-bis {4- (3-sulfamoyl-4-aminophenoxy) phenyl} hexafluoropropane, 2,2-
Bis (3-carboxy-4-aminophenyl) hexafluoropropane, 2,2-bis {4- (3-carboxy-
4-aminophenoxy) phenyl @ hexafluoropropane,

1,3-bis [2- {4- (4-aminophenoxy) phenyl} hexafluoroisopropyl] benzene p-bis (3-carboxy-4-aminophenoxy) tetrafluorobenzene, 4,4'-bis (3-carboxy-4-aminophenoxy) octafluorobiphenyl, 4,4′-diaminooctafluorobiphenyl,
1,2-bis (3-carboxy-4-aminophenyl)
Tetrafluoroethane, 1,3-bis (3-carboxy-
4-aminophenyl) hexafluoropropane, 1,5
-Bis (3carboxy-4-aminophenyl) decafluoropentane, diaminobenzotrifluoride, bis (trifluoromethyl) phenylenediamine, diaminotetra (trifluoromethyl) benzene, diamino (pentafluoroethyl) benzene, 2,2 ′ -Bis (trifluoromethyl) benzidine, 2,2'-bis (trifluoromethyl) -4,4'-diaminodiphenyl ether, bis (aminophenoxy) di (trifluoromethyl) benzene, bis (aminophenoxy) tetrakis (tri Fluoromethyl) benzene, bis [(trifluoromethyl) aminophenoxy] benzene, bis [(trifluoromethyl) aminophenoxy] biphenyl, bis {[(trifluoromethyl) aminophenoxy] phenyl} hexafluoropropa Hexamethylene diamine,
Heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, tetramethylenediamine, propylenediamine, 3-methylheptamethylenediamine, 4,4-dimethylheptamethylenediamine,

2,12-diaminododecane, 1,2-bis (3-aminopropoxy) ethane, 2,2-dimethylpropylenediamine, 3-methoxy-hexamethylenediamine, 2,5-dimethylhexamethylenediamine,
2,5-dimethylheptamethyldiamine, 5-methylnonamethylenediamine, 2,17-diaminoicosadecane, 1,4-diaminocyclohexane, 1,10-diamino-1,10-dimethyldecane, 1,18-diamino Octadecane, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 3,3'-diethyl-4,4'-
Diaminodiphenylmethane, 3,3'-dimethoxy-
4,4'-diaminodiphenylmethane, 3,3'diethoxy-4,4'-diaminodiphenylmethane, 3,3 '
-Difluoro-4,4'-diaminodiphenylmethane,
3,3'-dichloro-4,4'diaminodiphenylmethane, 3,3'-dibromo-4,4'-diaminodiphenylmethane, 3,3'-di (trifluoromethyl) -4,
4'-diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminodiphenyl ether, 3,3'-
Diisopropyl-4,4'-diaminodiphenylether, 3,3'-dimethoxy-4,4'-diaminodiphenylether, 3,3'-diethoxy-4,4'-diaminodiphenylether, 3,3'-difluoro-4,
4'-diaminodiphenyl ether, 3,3'-dichloro-4,4'-diaminodiphenyl ether, 3,3 '
-Dibromo-4,4'-diaminodiphenyl ether,
3,3′-di (trifluoromethyl) -4,4′-diaminodiphenyl ether,

3,3'-dimethyl-4,4'-diaminodiphenylsulfone, 3,3'-dimethoxy-4,4 '
-Diaminodiphenylsulfone, 3,3'-diethoxy-4,4'-diaminodiphenylsulfone, 3,3'-
Difluoro-4,4'-diaminodiphenyl sulfone,
3,3'-dichloro-4,4'-diaminodiphenylsulfone, 3,3'-dibromo-4,4'-diaminodiphenylsulfone, 3,3'-di (trifluoromethyl)
-4,4'-diaminodiphenylsulfone, 3,3'-
Dimethyl-4,4'-diaminodiphenylpropane,
3,3'-dimethoxy-4,4'-diaminodiphenylpropane, 3,3'-diethoxy-4,4'-diaminodiphenylpropane, 3,3'-difluoro-4,4 '
-Diaminodiphenylpropane, 3,3'-dichloro-
4,4′-diaminodiphenylpropane, 3,3′-dibromo-4,4′-diaminodiphenylpropane,
3'-di (trifluoromethyl) -4,4'-diaminodiphenylpropane, 3,3'-dimethyl-4,4'diaminodiphenyl sulfide, 3,3'-dimethoxy-
4,4 ′ diaminodiphenyl sulfide, 3,3′-diethoxy-4,4′-diaminodiphenyl sulfide,
3,3'-difluoro-4,4'-diaminodiphenyl sulfide, 3,3'-dichloro-4,4'-diaminodiphenyl sulfide, 3,3'-dibutomo-4,4 '
-Diaminodiphenyl sulfide, 3,3'-di (trifluoromethyl) -4,4'-diaminodiphenyl sulfide,

3,3'-dimethyl-4,4'-diaminodiphenylhexafluoropropane, 3,3'-dimethoxy-4,4'-diaminodiphenylhexafluoropropane, 3,3'-diethoxy-4,4 ' -Diaminodiphenylhexafluoropropane, 3,3'-difluoro-
4,4′-diaminodiphenylhexafluoropropane, 3,3′-dichloro-4,4′-diaminodiphenylhexafluoropropane, 3,3′-dibromo-4,
4'-diaminodiphenylhexafluoropropane,
3,3′-di (trifluoromethyl) -4,4′-diaminodiphenylhexafluoropropane, 3,3′-dimethyl-4,4′-diaminobenzophenone, 3,3 ′
-Dimethoxy-4,4'-diaminobenzophenone,
3,3'-diethoxy-4,4'-diaminobenzophenone, 3,3'-difluoro-4,4'-diaminobenzophenone, 3,3'-dichloro-4,4'-diaminobenzophenone, 3,3'- Dibromo-4,4'-diaminobenzophenone, 3,3'-di (trifluoromethyl) -4,4'-diaminobenzophenone, 3,3'-
Dimethylbenzidine, 3,3 ′, 5,5′-tetramethyl-4,4′-diaminodiphenylmethane, 3,3 ′,
5,5′-tetraisopropyl-4,4′-diaminodiphenylmethane, 3,3 ′, 5,5′-tetramethoxy-4,4′-diaminodiphenylmethane, 3,3 ′,
5,5'-tetraethoxy-4,4'-diaminodiphenylmethane, 3,3 ', 5,5'-tetrafluoro-
4,4'-diaminodiphenylmethane, 3,3 ', 5
5'-tetrachloro-4,4'-diaminodiphenylmethane, 3,3 ', 5,5'-tetrabromo-4,4'-
Diaminodiphenylmethane, 3,3 ′, 5,5′-tetra (trifluoromethyl) -4,4′-diaminodiphenylmethane,

3,3 ', 5,5'-tetramethyl-4,
4'-diaminodiphenyl ether, 3,3 ', 5
5'-tetraethyl-4,4'-diaminodiphenyl ether, 3,3 ', 5,5'-tetramethoxy-4,4'
-Diaminodiphenyl ether, 3,3 ', 5,5'-tetraethoxy-4,4'-diaminodiphenyl ether,
3,3 ′, 5,5′-tetrafluoro-4,4′-diaminodiphenyl ether, 3,3 ′, 5,5′-tetrachloro-4,4′-diaminodiphenyl ether, 3,
3 ′, 5,5′-tetrabromo-4,4′-diaminodiphenyl ether, 3,3 ′, 5,5′-tetra (trifluoromethyl) -4,4′-diaminodiphenyl ether, 3,3 ′, 5 5'-tetramethyl-4,4'-
Diaminodiphenyl sulfone, 3,3 ′, 5,5′-tetramethoxy-4,4′-diaminodiphenyl sulfone,
3,3 ', 5,5'-tetraethoxy-4,4'-diaminodiphenylsulfone, 3,3', 5,5'-tetrafluoro-4,4'-diaminodiphenylsulfone, 3,
3 ′, 5,5′-tetrachloro-4,4′-diaminodiphenylsulfone, 3,3 ′, 5,5′-tetrabromo-4,4′-diaminodiphenylsulfone, 3,3 ′,
5,5'-tetra (trifluoromethyl) -4,4'-
Diaminodiphenyl sulfone, 3,3 ′, 5,5′-tetramethyl-4,4′-diaminodiphenylpropane,
3,3 ′, 5,5′-tetramethoxy-4,4′-diaminodiphenylpropane, 3,3 ′, 5,5′-tetraethoxy-4,4′-diaminodiphenylpropane, 3,
3 ′, 5,5′-tetrafluoro-4,4′-diaminodiphenylpropane, 3,3 ′, 5,5′-tetrachloro-4,4′-diaminodiphenylpropane, 3,3 ′,
5,5′-tetrabromo-4,4′-diaminodiphenylpropane, 3,3 ′, 5,5′-tetra (trifluoromethyl) -4,4′-diaminodiphenylpropane,

3,3 ', 5,5'-tetramethyl-4
4'-diaminodiphenyl sulfide, 3,3 ', 5
5'-tetramethoxy-4,4'-diaminodiphenyl sulfide, 3,3 ', 5,5'-tetraethoxy-
4,4′-diaminodiphenyl sulfide, 3,3 ′,
5,5′-tetrafluoro-4,4′-diaminodiphenyl sulfide, 3,3 ′, 5,5′-tetrachloro-
4,4′-diaminodiphenyl sulfide, 3,3 ′,
5,5′-tetrabromo-4,4′-diaminodiphenyl sulfide, 3,3 ′, 5,5′-tetra (trifluoromethyl) -4,4′-diaminodiphenyl sulfide, 3,3 ′, 5,5 '-Tetramethyl-4,4'-diaminodiphenylhexafluoropropane, 3,3',
5,5′-tetramethoxy-4,4′-diaminodiphenylhexafluoropropane, 3,3 ′, 5,5′-tetraethoxy-4,4′-diaminodiphenylhexafluoropropane, 3,3 ′, 5 5′-tetrafluoro-4,4′-diaminodiphenylhexafluoropropane, 3,3 ′, 5,5′-tetrachloro-4,4′-diaminodiphenylhexafluoropropane, 3,3 ′,
5,5′-tetrabromo-4,4′-diaminodiphenylhexafluoropropane, 3,3 ′, 5,5′-tetra (trifluoromethyl) -4,4′-diaminodiphenylhexafluoropropane,

3,3 ', 5,5'-tetramethyl-4,
4'-diaminobenzophenone, 3,3 ', 5,5'-
Tetramethoxy-4,4′-diaminobenzophenone,
3,3 ′, 5,5′-tetraethoxy-4,4′-diaminobenzophenone, 3,3 ′, 5,5′-tetrafluoro-4,4′-diaminobenzophenone, 3,3 ′,
5,5'-tetrachloro-4,4'-diaminobenzophenone, 3,3 ', 5,5'-tetrabromo-4,4'
-Diaminobenzophenone, 3,3 ', 5,5'-tetra (trifluoromethyl) -4,4'-diaminobenzophenone, 3,3', 5,5'-tetraisopropyl-
4,4'-diaminodiphenylmethane, 3,3'-diisopropyl-5,5'-dimethyl-4,4'-diaminodiphenylmethane, 3,3'-diisopropyl-5
5'-diethyl-4,4'-diaminodiphenylmethane, 3,3'-diisopropyl-5,5'-dimethyl-
4,4'-diaminodiphenyl ether, 3,3'-diisopropyl-5,5'-diethyl-4,4'-diaminodiphenyl ether, 3,3'-diisopropyl-
5,5′-dimethyl-4,4′-diaminodiphenylpropane, 3,3′-diisopropyl-5,5′-diethyl-4,4′-diaminodiphenylpropane, 3,3 ′
-Diisopropyl-5,5'-dimethyl-4,4'-diaminodiphenylsulfone, 3,3'-diisopropyl-5,5'-diethyl-4,4'-diaminodiphenylsulfone, 3,3'-bis (tri Fluoromethyl) benzidine, 2,2′-bis (trifluoromethyl) -4,
4'-diaminodiphenyl ether, 3,3'-bis (trifluoromethyl) -4,4'-diaminodiphenyl ether, 3,3 ', 5,5'-tetrakis (trifluoromethyl) -4,4'-diaminodiphenyl ether , 3,3'-bis (trifluoromethyl) -4,4 '
-Diaminobenzophenone and the like, and two or more of these may be used in combination.

In producing the polyimide resin,
The tetracarboxylic dianhydride and the diamine are reacted at an appropriate temperature. In this reaction, the degree of imidization can be appropriately adjusted by selecting appropriate conditions. For example, to produce a completely or almost completely imidized polyimide by reacting at 100 ° C. or higher, particularly 120 ° C. or higher, if necessary, in the presence of a catalyst such as tributylamine, triethylamine, and triphenyl phosphite. (The catalyst is preferably used in an amount of 0 to 15% by weight based on the total amount of the reaction components, and more preferably 0.1 to 15% by weight.
When the reaction is carried out at 80 ° C. or less, particularly at 50 ° C. or less, it is a precursor of the polyimide and is completely or almost not imidized.
Polyamic acid can be produced. Further, a polyimide precursor in which imidization has partially progressed can be produced.

The polyamic acid or the polyimide precursor partially imidized is further heated at 100 ° C.
Above, particularly a method of imidization by heating to 120 ° C. or higher, acetic anhydride, propionic anhydride, acid anhydrides such as benzoic anhydride, ring-closing agents such as carbodiimides such as dicyclohexylcarbodiimide, and pyridine and isoquinoline as needed. Chemical ring closure (imidization) in the presence of a ring closure catalyst such as trimethylamine, aminopyridine, imidazole, etc.
(Preferably, the ring-closing agent and the ring-closing catalyst are used in a range of 1 to 8 mol per 1 mol of the acid anhydride) to produce a polyimide in which imidation is almost or completely completed. it can. These reactions are preferably performed in the presence of an organic solvent.

Organic polar solvents usable in the above reaction include N, N-dimethylformamide, N, N-
Dimethylacetamide, N-methyl-2-pyrrolidone,
Dimethyl sulfoxide, hexamethylphosphoramide,
There are phenol, m-cresol, chlorobenzene and the like, and two or more kinds thereof may be used as a mixture as long as they are compatible with each other. In addition, along with these organic polar solvents, toluene,
General-purpose solvents such as xylene, cellosolve acetate, and methyl cellosolve can be used in combination as long as the solubility of the polyimide resin or its precursor is not reduced. There is no particular limitation on the order in which the reactants are added.

In the polyimide resin thus obtained, a polyimide precursor, particularly a polyamic acid,
It is dissolved in N, N-dimethylacetamide at a concentration of 0.1 g / dl and has a reduced viscosity of 0.1 d when measured at 30 ° C.
It is preferably at least 1 / g.

The material for the liquid crystal alignment film contains the above-mentioned polyimide resin, and is preferably a material obtained by dissolving this polyimide resin in an organic solvent (varnish). As the organic solvent, those exemplified above as those which can be used in the production of the polyimide resin can be used. The selection of the organic solvent to be used is determined in consideration of the solubility of the polyimide-based resin. Among the polyimide-based resins, a polyimide precursor such as polyamic acid has good solubility in the organic solvent.

In addition to the polyimide resin or the polyamic acid resin, additives may be used for the liquid crystal alignment film material. Examples of the additives used herein include benzophenones such as benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, Michler's ketone, chloroacetophenone, diethoxyacetophenone, 4-phenoxydichloroacetophenone and 4-benzophenone. t-butyldichloroacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1- ( Acetophenones such as 4-methylthiophenyl) -morpholinopropan-1-one, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoy Isopropyl ether,
Benzoins such as benzylmethyl ketal, thioxanthone such as thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone and isopropylthioxanthone; Dimethyl 2,2'-azobisisobutyrate, 1,1'-azobis- (cyclohexane-1
Azo compounds such as 2,2 -'- azobis (2,4-dimethylvaleronitrile), azobisisobutyronitrile, 2,2'-azobis- (4-methoxy-2,4-dimethylvaleronitrile), 2,2- Bis-((4-stearylamino) phenoxyphenyl)
There are compounds having a long aliphatic chain such as propane and 2,2-bis-((4-laurylamino) phenoxyphenyl) propane, and these may be used in combination of two or more. The amount of the additive to be used is set at 0.1 to the weight of the polyimide resin or the polyamic acid resin in the liquid crystal alignment film material.
01 to 60% by weight. If the amount is less than 0.01% by weight, the effect of changing the pretilt is small.

The material for a liquid crystal alignment film is applied on a suitable substrate such as a glass substrate on which a transparent electrode such as ITO (Indium Tin Oxide) is formed in advance, and dried to form a polyimide layer. As a coating method, a spin core
, A dipping method, a printing method, a spraying method, and the like. The drying temperature is 100 to 250 ° C, preferably 150 to
Although it is selected in the range of 230 ° C., when a polyimide precursor such as polyamic acid is used as the polyimide resin, the temperature is set to a temperature equal to or higher than the temperature at which ring closure occurs.
C. or higher is preferable, and particularly 180.degree. C. or higher is preferable. The heating time is preferably from 1 minute to 6 hours, particularly preferably from 1 minute to 3 hours. In order to improve the adhesion between the substrate and the polyimide layer, a coupling agent such as a silane coupling agent or a titanium coupling agent may be used between them.

In the present invention, a predetermined portion of the surface of the resin layer containing polyimide and polyamic acid is irradiated with light to be used as a liquid crystal alignment film. A liquid crystal display device can be obtained by a known method using the liquid crystal holding substrate having the liquid crystal alignment film.

EXAMPLES The present invention will be described below with reference to examples, but the scope of the present invention is not limited by these examples. Synthesis Example 1 In a four-necked flask equipped with a thermometer, a stirrer, a nitrogen inlet tube, and a drying tube, 8 g of N-methylpyrrolidone and 1.03 g (9.5 mmol) of p-phenylenediamine, 1,3-bis (amino) Propyl) -tetramethyldisiloxane
12 g (0.5 mol) was added and stirred until a homogeneous solution was obtained. After the diamine is dissolved, 3,4,3 ', 4'-
1.84 g (6 mmol) of tetracarboxylic dianhydride,
2.08 g (4 mmol) of 1,10-decanediol bis (trimellitic anhydride) was added little by little. After the addition was completed, stirring was performed for 5 hours to obtain a polyamic acid solution.

Synthesis Example 2 In a four-necked flask equipped with a thermometer, a stirrer, a nitrogen inlet tube, and a drying tube, 8 g of N-methylpyrrolidone and 1.2 g (9 mmol) of p-phenylenediamine 1,3-bis ( 0.25 g of aminopropyl) -tetramethyldisiloxane
(1 mmol), and stirred until a homogeneous solution was obtained. After dissolution of the diamine, 0.99 g (5 mmol) of butanetetracarboxylic dianhydride and 2.61 g (5,10-decanediol bis (trimellitic anhydride) of
Mmol) was added in small portions. After addition is complete, stir 5
After a period of time, a solution of polyamic acid was obtained.

Synthesis Example 3 N-methylpyrrolidone (8 g) and p-phenylenediamine (0.86 g (8 mmol), 1,3-bis) were placed in a four-necked flask equipped with a thermometer, a stirrer, a nitrogen inlet tube, and a drying tube. (Aminopropyl) -tetramethyldisiloxane 0.5
g (2 mmol) was added and stirred until a homogeneous solution was obtained. After the diamine is dissolved, 1.84 g of 3,4,3 ', 4'-bicyclohexyltetracarboxylic dianhydride is obtained.
(6 mmol) and 2.61 g (5 mmol) of 1,10-decanediol bis (trimellitic anhydride) were added little by little. After the addition was completed, stirring was performed for 5 hours to obtain a polyamic acid solution.

Synthesis Example 4 N-methylpyrrolidone (8 g) and p-phenylenediamine (1.08 g, 10 mmol) were placed in a four-necked flask equipped with a thermometer, a stirrer, a nitrogen inlet tube, and a drying tube to obtain a homogeneous solution. Stir until it is. After the diamine has dissolved,
2.94 g (10 mmol) of 3,4,3 ', 4'-biphenyltetracarboxylic dianhydride were added in small portions.
After the addition was completed, stirring was performed for 5 hours to obtain a polyamic acid solution.

Examples 1 to 3 and Comparative Example 1 The polyamic acid solutions obtained in Synthesis Examples 1 to 4 were diluted with N-methylpyrrolidone so that the solid content was 5% by weight. The solution was spin-coated on two glass substrates with ITO transparent electrodes. After that, pre-dry at 100 ° C for 1 minute,
Full curing and rubbing were performed at 200 ° C. for 30 minutes. Light irradiation was performed after the steps shown in Table 1. Next, the two substrates were combined with their polyimide layers facing each other so that the rubbing direction was antiparallel, and the surroundings were sealed with a room temperature-curable epoxy adhesive. Liquid crystal ZLI-4792 (trade name, manufactured by Merck) was sealed in these test liquid crystal cells at room temperature. After heating the obtained liquid crystal cell at 130 ° C. for 1 hour,
The pretilt angle was measured. Table 1 shows the results.

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[Table 1] 光 Type of light irradiation lamp used Pretilt angle (Degree) Polyimide Timing (irradiation amount J / cm ² ) Unirradiated part Irradiated part ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ━━━━ Example 1 Synthesis example 1 After pre-curing Mercury xenon 12.8 1.8 Lamp (10) ─────────────────────────── ───────── Example 2 Synthesis example 2 After pre-curing Mercury xenon 5.3 0.3 Lamp (5) ──────────────────── Example 3 Synthesis Example 3 After pre-curing Mercury xenon 4.3 0.5 lamp (2)例 Example Synthesis Example 1 Low-pressure mercury after full curing 12.3 0.8 Lamp (1) ────────────────────────────────── ── Example 5 Synthesis Example 2 After rubbing Excimer 5.3 0.2 Laser (0.3) ────────────────────────── ────────── Comparative example 1 Synthesis example 4 After rubbing Mercury xenon 3.3 3.2 Lamp (5) ━━━━━━━━━━━━━━━━━━━━ ━━━━━━━━━━━━━━━━

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According to the liquid crystal alignment film of the present invention, by irradiating the surface with light, portions having different pretilt angles of liquid crystal molecules can be formed.

Continuing on the front page (72) Inventor Yasuhisa Odagawa 48, Wadai, Tsukuba, Ibaraki Hitachi Chemical Co., Ltd.Tsukuba Development Laboratory (72) Inventor Yasuo Miyadera 48, Wadai, Tsukuba, Ibaraki Hitachi Tsukuba Development Co., Ltd. Inside the research laboratory (72) Inventor Yuichi Kanaya 4-3-1-1, Higashicho, Hitachi City, Ibaraki Prefecture Inside the Ibaraki Research Laboratory, Hitachi Chemical Co., Ltd. (56) References JP-A-63-158526 (JP, A) JP-A-2-291527 (JP, A) JP-A-7-36047 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G02F 1/1337 525 C09K 19/56

Claims (3)

(57) [Claims] 1. A liquid crystal alignment film for aligning liquid crystal molecules used in a liquid crystal display device. The liquid crystal alignment film irradiates a predetermined portion of the surface with light in a range of 0.3 to 10 J / cm ^2. A liquid crystal alignment film, characterized in that the liquid crystal molecules thus formed have portions with different pretilt angles, and the alignment film contains a polymer of a repeating unit represented by the general formula (I). Embedded image (However, in the general formula (I), A is a residue of tetracarboxylic dianhydride except a cyclobutane ring , R is a divalent organic group,
A and / or R contains a siloxane structure. ) 2. A liquid crystal alignment film for aligning liquid crystal molecules used in a liquid crystal display device, wherein the liquid crystal alignment film irradiates a predetermined portion of the surface with light in a range of 0.3 to 10 J / cm ^2. A liquid crystal alignment film characterized in that the liquid crystal molecules thus formed have portions having different pretilt angles, and the alignment film contains a polymer of a repeating unit represented by the general formula (II). Embedded image (Where A in the general formula (II) is a residue of tetracarboxylic dianhydride excluding a cyclobutane ring , R is a divalent organic group,
A and / or R contains a siloxane structure. ) 3. The general formula according to claim 1 or claim 2.
(I) or the repeating unit represented by the general formula (II)
A material for a liquid crystal alignment film containing a limmer .