KR101492270B1 - Liquid crystal aligning agent, liquid crystal alignment film and liquid crystal display device - Google Patents

Abstract

The present invention relates to a liquid crystal aligning agent containing a polyamic acid having a divalent organic group represented by the following formula (II) as a group derived from a diamine or an imidized polymer thereof.

≪

(Wherein Y represents a single bond or a divalent organic group having 1 to 30 carbon atoms)

The present invention provides a liquid crystal aligning agent for providing a liquid crystal alignment film for a liquid crystal display element having excellent afterimage and baking properties.

A polyamic acid repeating unit, an imide repeating unit, an imidized polymer, a liquid crystal aligning agent, a liquid crystal alignment film, a liquid crystal display element

Description

TECHNICAL FIELD [0001] The present invention relates to a liquid crystal alignment material, a liquid crystal alignment film, and a liquid crystal display device,

The present invention relates to a liquid crystal aligning agent, a liquid crystal alignment film and a liquid crystal display element. More specifically, the present invention relates to a liquid crystal aligning agent having good afterimage characteristics, a liquid crystal alignment film obtained from the liquid crystal aligning agent, and a liquid crystal display element having the film.

At present, as a liquid crystal display element, a liquid crystal alignment film containing polyamic acid, polyimide, or the like is formed on the surface of a substrate on which a transparent conductive film is to be provided to form a substrate for a liquid crystal display element. Two liquid crystal alignment films are disposed opposite to each other, Called TN (Twisted Nematic) type liquid crystal cell in which a nematic liquid crystal layer having a nematic liquid crystal layer is formed as a cell having a sandwich structure and the long axis of the liquid crystal molecule is continuously twisted by 90 degrees from one substrate toward the other TN type liquid crystal display devices are known. Further, STN (Super Twisted Nematic) type liquid crystal display elements and vertical orientation type liquid crystal display elements, which have higher contrast and less time dependency than TN type liquid crystal display elements, have been developed. This STN type liquid crystal display element uses a liquid crystal in which a chiral agent as an optically active material is blended with a nematic liquid crystal and a birefringence effect caused by a state in which the long axis of the liquid crystal molecule is continuously twisted over 180 degrees between the substrates . As a liquid crystal display element separate from the above, a multi-domain vertical alignment (MVA) system in which liquid crystal molecules having negative dielectric anisotropy are oriented perpendicularly to a substrate, a vertical alignment liquid crystal display element called a PVA (Patterned Vertical Alignment) Has been proposed. These MVA systems and PVA system liquid crystal display elements are excellent not only in viewing angle and contrast, but also in that they do not need to be subjected to rubbing treatment in the formation of a liquid crystal alignment film.

In any of these various methods, a desirable liquid crystal alignment film is required to have a short afterglow erase time of the liquid crystal display element.

An object of the present invention is to provide a liquid crystal aligning agent which provides a liquid crystal alignment film for a liquid crystal display element having excellent afterimage and baking properties.

Other objects and advantages of the present invention will become apparent from the following description.

The above objects and advantages of the present invention are achieved according to the present invention by firstly providing a process for producing a polymer comprising repeating units of at least one of an amic acid repeating unit represented by the following formula (I-1) and an imide repeating unit represented by the following formula Polymer, wherein Q ^{1 in} the formula I- ¹ or Q ² in the formula I-2 in the one or more repetition units is a divalent organic group represented by the following formula (II) .

<Formula I-1>

(Wherein P ¹ represents a tetravalent organic group constituting a tetracarboxylic acid, and Q ¹ represents a divalent organic group constituting a diamine)

&Lt; Formula (I-2) >

(Wherein P ² represents a tetravalent organic group constituting the tetracarboxylic acid, and Q ² represents a divalent organic group constituting the diamine)

&Lt;

(Wherein Y represents a single bond or a divalent organic group having 1 to 30 carbon atoms)

Further, according to the present invention, the above objects and advantages of the present invention are attained by the liquid crystal alignment film obtained from the liquid crystal aligning agent and the liquid crystal display element containing the same.

The liquid crystal alignment film formed by the liquid crystal aligning agent of the present invention provides a display device which does not cause afterimage that greatly degrades the display quality of the liquid crystal display element as compared with the display element using the conventional alignment film.

The liquid crystal display of the present invention can be effectively used in various devices and is preferably used as a display device such as a desk calculator, a wrist watch, a desk clock, a mobile phone, a coefficient display board, a word processor, a personal computer, .

Hereinafter, the present invention will be described in detail.

The liquid crystal aligning agent in the present invention includes a polymer having at least one of the repeating unit represented by the above formula (I-1) and the repeating unit represented by the above formula (I-2).

The polymer may be a mixture of a polyamic acid having a repeating unit represented by the formula (I-1) and a polyimide having a repeating unit represented by the formula (I-2) May be a polymer having all of the repeating units represented by the general formula (I-2).

The polyamic acid is obtained by ring-opening the tetracarboxylic dianhydride and the diamine compound, and the polyimide is usually obtained by dehydration ring closure of the polyamic acid.

&Lt; Polyamic acid and polyimide &

[Tetracarboxylic acid dianhydride]

The tetravalent organic group represented by P ¹ in the repeating unit (amic acid unit) represented by the above formula (I-1) and the tetravalent organic group represented by the repeating unit (imide unit) P ² represented by the above formula The organic group is a group derived from a tetracarboxylic dianhydride. Examples of the tetracarboxylic dianhydride include butane tetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2-dimethyl-1,2,3,4- Cyclobutane tetracarboxylic acid dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic acid dianhydride, 1,3-dichloro-1,2,3,4-cyclobutanetetracar Tetramethyl-1,2,3,4-cyclobutane tetracarboxylic acid dianhydride, 1,2,3,4-cyclopentanetetracarboxylic acid dianhydride, 1,2,3,4- 1,2,4,5-cyclohexanetetracarboxylic acid dianhydride, 3,3 ', 4,4'-dicyclohexyltetracarboxylic acid dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride , 3,5,6-tricarboxy norbornane-2-acetic acid dianhydride, 2,3,4,5-tetrahydrofuran tetracarboxylic acid dianhydride, 1,3,3a, 4,5,9b-hexa (Tetrahydro-2,5-dioxo-3-furanyl) -naphtho [l, 2-c] 3,3a, 4,5,9b-hexahydro-5-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [ 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) [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-7-ethyl-5- (tetrahydro- Furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro- -Dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro- 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] Tetrahydrofuran) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid dianhydride, bicyclo [2,2,2] -7-ene-2,3,5,6-tetracarboxylic acid dianhydride, 3-oxabicyclo [3.2.1] octane-2,4-dione-6-spiro-3 '- (tetrahydrofuran- I 2 ', 5'-dione), 3,5,6-tree-carboxy-2-carboxymethyl norbornane 2: 3,5: 6-dianhydride, 4,9- dioxa-tricyclo [5.3.1.0 ^{2 , 6} ] undecane-3,5,8,10-tetraone, bicyclo [3.3.0] octane-2,4,6,8-tetracarboxylic acid dianhydride, And aliphatic and / or alicyclic tetracarboxylic acid dianhydrides such as a compound represented by each of

(Wherein R ₁ and R ₃ independently represent a divalent organic group having an aromatic ring, R ₂ and R ₄ independently represent a hydrogen atom or an alkyl group, and plural R ₂ and R ₄ present are the same Or may be different)

Pyromellitic dianhydride, 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride, 2,3,3', 4'-benzophenonetetracarboxylic acid dianhydride, 2,2 ', 3 , 3'-benzophenonetetracarboxylic acid dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 2,2', 3,3'-biphenyltetracarboxylic acid dianhydride , 3,3 ', 4,4'-biphenylsulfonetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic acid dianhydride, 2,3,6,7-naphthalenetetracarboxylic acid Dianhydride, 3,3 ', 4,4'-biphenyl ether tetracarboxylic dianhydride, 3,3', 4,4'-dimethyldiphenylsilane tetracarboxylic acid dianhydride, 3,3 ', 4 , 4'-tetraphenylsilane tetracarboxylic acid dianhydride, 1,2,3,4-furan tetracarboxylic dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylsulfide Anhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylsulfone anhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylpropane dianhydride, 3,3 ' ,4 , 4'-perfluoroisopropylidene diphthalic acid dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, bis (phthalic acid) phenylphosphine oxide dianhydride, p-phenylene-bis (Triphenylphthalic acid) dianhydride, bis (triphenylphthalic acid) dianhydride, m-phenylene-bis (triphenylphthalic acid) dianhydride, bis (Diphenylmethane dianhydride), diphenylmethane dianhydride, ethylene glycol-bis (anhydrotrimellitate), propylene glycol-bis (anhydrotrimellitate), 1,4- Hexanediol-bis (anhydrotrimellitate), 1,8-octanediol-bis (anhydrotrimellitate), 2,2-bis (4-hydroxyphenyl) propane- , And aromatic tetracarboxylic acid dianhydrides represented by the following formulas (3) to (5), respectively.

These tetracarboxylic acid dianhydrides may be used singly or in combination of two or more.

In the tetracarboxylic acid dianhydride exemplified above, 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid dianhydride Water, 1,2,3,4-cyclopentanetetracarboxylic acid dianhydride, 1,2,4,5-cyclohexanetetracarboxylic acid dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 5- (2,5-dioxotetrahydrofuran) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid dianhydride, 1,3,3a, 4,5,9b-hexahydro- - (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan- 1,3 -dione, 1,3,3a, 4,5,9b- hexahydro- (Tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5, (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 acid dianhydride, 3-oxabicyclo [3.2.1] octane- -3 '- (tetrahydrofuran-2', 5'-dione), 3,5,6-tricarboxy-2-carboxymethylnorbornane- Tetra-carboxylic acid dianhydride, the compound represented by each of the following formulas (6) to (8) in the compound represented by the above formula (1) ), A compound represented by the following formula (9), pyromellitic dianhydride, 3,3 ', 4,4'-benzophenonetetracarboxylic acid dianhydride, 2,3,3', 4 ' Benzophenone tetracarboxylic acid dianhydride, 2,2 ', 3,3'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-biphenyltetracarboxylic dianhydride, 3, 3 ', 4,4'-biphenylsulfonetetracarboxylic dianhydride and 1,4,5,8-naphthalenetetracarboxylic dianhydride are preferable from the viewpoint of being able to exhibit good liquid crystal alignability. Particularly preferred are pyromellitic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetra 2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl (Tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 3-oxabicyclo [3.2.1] , 4-dione-6-spiro-3 '- (tetrahydrofuran-2', 5'-dione), 3,5,6-tricarboxy-2-carboxymethylnorbornane- Dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] undecane-3,5,8,10-tetraone, bicyclo [3.3.0] octane-2,4,6,8 -Tetracarboxylic acid dianhydride, and 1,2,3,4-cyclopentanetetracarboxylic acid dianhydride.

[Diamine compound]

The divalent organic group represented by Q ¹ in the repeating unit (amic acid bonding unit) represented by the above formula (I-1) and the divalent organic group represented by the formula (I-2) Organic groups are all derived from diamine compounds.

At least one of Q ¹ in the formula (I-1) or Q ² in the formula (I-2) which is a repeating unit constituting the polymer contains a divalent organic group represented by the following formula (II).

&Lt;

(Wherein Y represents a single bond or a divalent organic group having 1 to 30 carbon atoms)

As a divalent organic group having 1 to 30 carbon atoms, a group represented by the following formula (II-1) is preferred.

&Lt; Formula (II-1) >

Examples of Z include an alkyl group, a halogen atom, and a nitro group. As concrete compounds, for example, compounds represented by the following formulas (II-2) and (II-3) are preferable.

&Lt; Formula (II-2) >

&Lt; Formula (II-3) >

Further, other diamine compounds different from the diamine compound may be used together with the diamine compound to such an extent that the effect of the present invention is not impaired. The other diamine compound used in the synthesis of the polymer contained in the liquid crystal aligning agent of the present invention preferably contains a pretilt angular expression component represented by the following formula (10) or (11).

(10)

(10)

(Wherein R ₅ and R ₆ are each independently a hydrogen atom or a methyl group, R ₇ is a linear or branched alkyl group having 1 to 20 carbon atoms, and R ₈ and R ₉ are each independently a divalent group Device)

(11)

(11)

(Wherein, a is 0 or 1 and R ₁₀ is an ether bond (-O-), a carbonyl group (-CO-), a carbonyloxy group (-COO-), an oxycarbonyl group (-OCO-) -NHCO-, -CONH-), a thioether bond (-S-) and a methylene group, R ₁₁ is a divalent organic group different from R ₁₀ , R ₁₂ is a steroid skeleton A group having a fluorine atom, or a group having a straight chain alkyl group having 1 to 22 carbon atoms)

These diamines having these pretilt angular expression components may be used singly or in combination of two or more.

As specific preferred examples of the diamine represented by the formula (10), for example, compounds represented by the following formulas (12) and (13) are exemplified.

(12)

(12)

(13)

(13)

As specific preferred examples of the diamine represented by the formula (11), for example, compounds represented by the following formulas (14) to (18) are exemplified.

When the liquid crystal aligning agent of the present invention is used in TN mode, STN mode or the like, it is preferable to use a diamine having a pretilt angular expression component represented by each of the above formulas (12) to (18) It is possible to stably express the pretilt angle of liquid crystal of 30 DEG. In this case, the proportion of the diamines having these pretilt angular expression components is preferably 0.5 to 30 mol%, more preferably 0.7 to 20 mol%, particularly preferably 1 to 15 mol%, based on the total diamine, to be.

When the liquid crystal aligning agent of the present invention is used in the VA system, it is preferable to use a compound represented by the formula (14) or (15) among the diamines having the pretilt angular expression component, Is particularly preferable. The proportion of these diamines is preferably 8 to 60 mol%, more preferably 9 to 50 mol%, particularly preferably 10 to 25 mol%, based on the total diamine.

When the liquid crystal aligning agent of the present invention is used in the IPS system or the FFS system, the diamine having the pretilt angular expression component may be used. However, the diamine having the pretilt angular expression component other than the diamine compound having the pretilt angular expression component Polymers can be synthesized using only diamine compounds.

Examples of the diamine compound other than the diamine compound containing the pretilt angular expression component used in the synthesis of the polymer for use in the liquid crystal aligning agent of the present invention include the following diamines.

p-phenylenediamine, m-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylethane, 4,4'-diaminodiphenylsulfide, 4,4 ' Diaminodiphenylsulfone, 2,2'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diaminobenzanilide, 4,4'-diaminodiphenyl ether, 1,5-dia Amino-1- (4'-aminophenyl) -1,3,3-trimethylindane, 6-amino-1- ( 4'-aminophenyl) -1,3,3-trimethylindane, 3,4'-diaminodiphenyl ether, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, Bis (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 2,2-bis Bis (4-aminophenoxy) phenyl] sulfone, 1,4-bis (4-aminophenoxy) -Bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 9,9- Phenyl) -10-hydroanthracene, 2,7-diaminofluorene, 9,9-bis (4-aminophenyl) fluorene, 4,4'- , 5,5'-tetrachloro-4,4'-diaminobiphenyl, 2,2'-dichloro-4,4'-diamino-5,5'-dimethoxybiphenyl, 3,3'- 4,4'-diaminobiphenyl, 1,4,4 '- (p-phenyleneisopropylidene) bisaniline, 4,4' - (m-phenyleneisopropylidene) (4-amino-2-trifluoromethylphenoxy) phenyl] hexafluoropropane, 4,4'-diamino-2,2'-bis (trifluoromethyl) biphenyl , 4,4'-diamino-2,2'-dimethylbiphenyl, 4,4'-bis [(4-amino-2-trifluoromethyl) phenoxy] -octafluorobiphenyl, Aromatic diamines such as bis (4-aminophenoxy) -2,2-dimethylpropane and 4,4'-bis (4-aminophenoxy) biphenyl;

Diaminopyridine, 5, 6-diamino-2,3-dicyanopyrimidine, 5, 6-diamino-2,3-dicyanopyrimidine, Dihydroxypyrimidine, 2,4-diamino-6-dimethylamino-1,3,5-triazine, 1,4-bis (3-aminopropyl) piperazine, Diamino-6-isopropoxy-1,3,5-triazine, 2,4-diamino-6-methoxy-1,3,5-triazine, 2,4- 2,4-diamino-6-methyl-s-triazine, 2,4-diamino-1,3,5-triazine, 4,6- 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-ethoxy acridactate, 3,8-diamino-6-phenylphenanthridine, (4-aminophenyl) phenylamine, and compounds represented by the following chemical formulas (19) and (20) Here diamine having a nitrogen atom other than two primary amino groups and the primary amino groups in the;

(19)

(19)

(Wherein R ₁₃ represents a monovalent organic group having a ring structure including a nitrogen atom selected from pyridine, pyrimidine, triazine, piperidine and piperazine, and X represents a divalent organic group)

(20)

(20)

(Wherein R ₁₄ represents a divalent organic group having a ring structure including a nitrogen atom selected from pyridine, pyrimidine, triazine, piperidine and piperazine)

There may be mentioned 1,3-bis (aminomethyl) cyclohexane, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, Methylenediamine, 1,4-diaminocyclohexane, isophoronediamine, tetrahydrodicyclopentadienylenediamine, hexahydro-4,7-methanedanilinedimethylenediamine, tricyclo [6.2.1.0 ^2,7 ] (Aminomethyl) cyclohexane, 1, 4-cyclohexanediamine, 4,4'-methylenebis (cyclohexylamine), 1,1-methoxysilylenediamine, Aliphatic and alicyclic diamines such as 4-bis (aminomethyl) cyclohexane; A diaminoorganosiloxane represented by the following formula (21);

(21)

(21)

(Wherein R ₁₅ represents a hydrocarbon group of 1 to 12 carbon atoms, plural R _{15 s} present may be the same or different, p is an integer of 1 to 3, and q is an integer of 1 to 20) These other diamine compounds other than the diamine compound containing the expression component may be used alone or in combination of two or more.

Of these, p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfide, 1,5-diaminonaphthalene, 2,7-diaminofluorene, 4 , 4'-diaminodiphenyl ether, 9,9-bis (4-aminophenyl) fluorene, 2,2-bis [4- Bis (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 1,4- 4,4'-diamino-2,2'-bis (trifluoromethyl) biphenyl, 4,4'-diamino-2,2'-dimethylbiphenyl, Diaminopyridine, 2,4-diaminopyrimidine, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-ditrifluoro 4,4'-diaminobiphenyl, 2,7-diaminofluorene, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, Bipyridyl) bisaniline, 4,4 '- (m-phenylenediisopropylidene) Dianaminocarbazole, N-methyl-3,6-diaminocarbazole, N-ethyl-N, N-diisopropylcarbodiimide, Diaminocarbazole, N, N'-di (4-aminophenyl) -benzidine, 3,6-diaminoacridine, (22), a compound represented by the following formula (23) in the compound represented by the formula (20), a compound represented by the following formula (23), a compound represented by the formula Oxy-2,4-diaminobenzene, pentadecanoxy-2,4-diaminobenzene, hexadecaneoxy-2,4-diaminobenzene, octadecanoxy- 2,5-diaminobenzene, pentadecaneoxy-2,5-diaminobenzene, hexadecaneoxy-2,5-diaminobenzene, octadecaneoxy-2,5-diaminobenzene, 1,4-cyclohexane Diamine, 4,4'-methylenebis (cyclohexylamine), the formula (21) , The formula (24) 3, 3 'of the compound represented by - (tetramethyldisiloxane-1,3-diyl) bis (propylamine) are preferred.

Particularly preferable examples include p-phenylenediamine, 4,4'-diaminodiphenylmethane, 2,2'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diaminodiphenyl ether (2,2-bis [4- (4-aminophenoxy) phenyl] -2,3-dimethylphenyl] Propane, 1,3-bis (aminomethyl) cyclohexane, 2,2-bis (4-aminophenyl) hexafluoropropane, 4,4'-diamino- Biphenyl.

[Synthetic reaction of polyamic acid]

The ratio of the tetracarboxylic dianhydride and the diamine compound to be used for the synthesis reaction of the polyamic acid is such that the ratio of the acid anhydride group of the tetracarboxylic dianhydride to the equivalent of the amino group contained in the diamine compound is 0.2 to 2 equivalents , And more preferably 0.3 to 1.2 equivalents.

The synthesis reaction of the polyamic acid is carried out in an organic solvent at a temperature of preferably -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 to be synthesized. Examples of the organic solvent include N-methyl-2-pyrrolidone, N, N-dimethylacetamide, Phenol type solvents such as m-cresol, xylenol, phenol, halogenated phenol and the like can be exemplified as non-protonic polar solvents such as dimethyl sulfoxide,? -Butyrolactone, tetramethyl urea, and hexamethylphosphotriamide. The amount (a) of the organic solvent used is preferably such that the total amount (b) of the tetracarboxylic dianhydride and the diamine compound is 0.1 to 30% by weight based on the total amount (a + b) of the reaction solution.

[Bad solvent]

Alcohols, ketones, esters, ethers, halogenated hydrocarbons, hydrocarbons, etc., which are poor solvents of polyamic acid, may be added to the organic solvent within a range that does not cause the production of the produced polyamic acid. Specific examples of such a poor solvent include alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol, cyclohexanol, ethylene glycol, propylene glycol, 1,4-butanediol, triethylene glycol, ethylene glycol monomethyl ether, Butyl acetate, 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-butyl ether, ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, Dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol moiety 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.

In this way, a reaction solution obtained by dissolving polyamic acid is obtained. The reaction solution is poured into a large amount of a poor solvent to obtain a precipitate, and the precipitate is dried under reduced pressure to obtain a polyamic acid. Alternatively, the reaction solution is distilled off under reduced pressure using an evaporator to obtain a polyamic acid. In addition, the polyamic acid can be purified by once or several times the step of dissolving the polyamic acid in an organic solvent and then precipitating it with a poor solvent. Alternatively, the polyamic acid can be purified by performing the step of distillation under reduced pressure using an evaporator once or several times.

[Synthesis of imidized polymer]

The imidized polymer constituting the liquid crystal aligning agent of the present invention can be synthesized by dehydrating and ring closure of the polyamic acid. The imidized polymer used in the present invention may be a partially dehydrated ring-closed polymer having an imidization rate of less than 100%. The &quot; imidization rate &quot; as used herein is a value indicating the proportion of the repeating unit having an imide ring or isoimide ring in the total repeating units of the polymer as a percentage. The dehydration ring closure of the polyamic acid can be carried out by a method of heating the polyamic acid (i), or (ii) by dissolving the polyamic acid in an organic solvent, adding a dehydrating agent and a dehydrating ring- Is done.

The reaction temperature in the method of heating the polyamic acid of (i) is preferably 50 to 200 占 폚, more preferably 60 to 170 占 폚. If the reaction temperature is less than 50 ° C, the dehydration ring-closure reaction is difficult to proceed sufficiently, and if the reaction temperature exceeds 200 ° C, the molecular weight of the resulting imidized polymer may be lowered.

On the other hand, in the method of adding the dehydrating agent and the dehydrating ring-closing catalyst in the solution of the polyamic acid of the above (ii), an acid anhydride such as acetic anhydride, propionic anhydride or trifluoroacetic anhydride can be used as the dehydrating agent. The amount of the dehydrating agent to be used is preferably 0.01 to 20 mol based on 1 mol of the repeating unit of the polyamic acid. As the dehydration cyclization catalyst, for example, tertiary amines such as pyridine, collidine, lutidine and triethylamine can be used. However, it is not limited to this. The amount of the dehydration ring-closing catalyst to be used is preferably 0.01 to 10 mol based on 1 mol of the dehydrating agent used. Examples of the organic solvent used in the dehydration ring closure reaction include the organic solvents exemplified for use in the synthesis of polyamic acid. The reaction temperature of the dehydration ring closure reaction is preferably 0 to 180 ° C, more preferably 10 to 150 ° C. In addition, the imidized polymer can be purified by performing the same operation as the method of purifying polyamic acid in the reaction solution thus obtained.

[Terminal formula]

The polyamic acid and imidized polymer of the present invention may be of a terminally modified type having a controlled molecular weight. By using the polymer of the terminal modification type, the effect of the present invention is not impaired and the coating properties and the like of the liquid crystal aligning agent can be improved. Such a terminal modification type can be synthesized by adding an acid anhydride, a monoamine compound, a monoisocyanate compound or the like to a reaction system when synthesizing a polyamic acid. Examples of the acid anhydride include maleic anhydride, phthalic anhydride, itaconic anhydride, n-decylsuccinic anhydride, n-dodecylsuccinic anhydride, n-tetradecylsuccinic anhydride, and n-hexadecylsuccinic anhydride. . Examples of the monoamine compound include aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-heptadecylamine, n-octadecylamine, n-octadecylamine, n-octadecylamine, n-hexadecylamine, - eicosylamine, and the like. Examples of the monoisocyanate compound include phenyl isocyanate and naphthyl isocyanate.

<Solution viscosity>

The polymer used in the alignment agent of the present invention preferably has a viscosity of 20 to 800 mPa · s, more preferably 30 to 500 mPa · s, when the solution is a 10 wt% solution.

The solution viscosity (mPa 占 퐏) of the polymer was measured at 25 占 폚 using an E-type rotational viscometer for a solution diluted to a solid concentration of 10% by weight using a predetermined solvent.

<Liquid Crystal Aligner>

The liquid crystal aligning agent of the present invention is preferably a polyamic acid synthesized by polycondensation reaction of a tetracarboxylic acid dianhydride and a diamine compound and / or an imidized polymer obtained by imidizing the polyamic acid, and preferably an epoxy group-containing compound Is dissolved and contained in an organic solvent.

Examples of the polymer used in the invention include (A) at least one polyamic acid alone, (B) at least one imidized polymer, and (C) a mixture of a polyamic acid and an imidized polymer. Among them, it is preferable to use a mixture of (B) at least one imidized polymer and (C) a mixture of a polyamic acid and an imidized polymer for the reason that the characteristics such as voltage holding ratio and residual DC become good.

When a mixture of (C) a polyamic acid and an imidized polymer is used, the imidization ratio in the imidized polymer is preferably in the range of 45 to 100%, and more preferably higher than 50% . At this time, 1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2,4,5- Cyclohexanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo 3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro- , 5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 3-oxabicyclo [3.2.1] octane- -3'- (tetrahydrofuran-2 ', 5'-dione) and pyromellitic dianhydride, and at least one tetracarboxylic acid dianhydride selected from the group consisting of p-phenylenediamine, 4,4' - diaminodiphenylmethane, 2,2'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diaminodiphenyl ether, 2,7-diaminofluorene, 3,3 '- (Tetramethyldisiloxane-1,3-diyl) bis (propylamine), 2,2-bis [4- (Aminophenoxy) phenyl] propane, 1,3-bis (aminomethyl) cyclohexane, 2,2-bis (4-aminophenyl) hexafluoropropane and 4,4'-diamino-2,2'-bis (Trifluoromethyl) biphenyl and a polyamic acid obtained by reacting at least one diamine selected from the group consisting of bisphenol A (bis (trifluoromethyl) biphenyl) and imidized polymer thereof, A liquid crystal alignment film in which the characteristics are improved can be obtained. In this case, the weight ratio of the polyamic acid and the imide polymer is preferably in the range of 10: 90 to 90: 10, more preferably in the range of the polyamic acid: imidized polymer = 30: 70 To 85:15, and particularly preferably in the range of polyamic acid: imidized polymer = 50:50 to 80:20.

The temperature at which the liquid crystal aligning agent of the present invention is produced is preferably from 0 캜 to 200 캜, more preferably from 20 캜 to 60 캜.

Examples of the organic solvent constituting the liquid crystal aligning agent of the present invention include the same solvents as those exemplified for use in the synthesis reaction of polyamic acid. However, in the synthesis reaction, a solvent may be selected only taking into account the solubility of raw materials or reactants, etc. However, as the liquid crystal aligning agent, it is necessary to further consider the storage stability and the printing properties and coating properties in subsequent steps, May be different from the organic solvent used in the synthesis reaction. Among them, a solvent having a boiling point of 160 deg. Examples of such a solvent include N-methyl-2-pyrrolidone, N, N-dimethylacetamide, dimethylsulfoxide,? -Butyrolactone, tetramethyl urea, hexamethylphosphoric triamide, But are not limited to, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, diacetone alcohol, butyl lactate, butyl acetate, ethylethoxypropionate, propylenecarbonate, (Ethylene glycol monobutyl ether (butyl cellosolve), 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, and N-methyl-2-pyrrolidone,? -Butyrolactone, diacetone alcohol, Ethylene glycol monobutyl ether (butyl cellosolve), propylene carbonate, and diethylene glycol diethyl ether are preferable. Particularly preferable solvent composition is a composition obtained by combining these solvents in which the polymer is not precipitated in the aligning agent and the surface tension of the aligning agent is in the range of 25 to 40 mN / m.

The solid concentration of the liquid crystal aligning agent of the present invention is selected in consideration of viscosity, volatility, and the like. Preferably 1 to 10% by weight. That is, the liquid crystal aligning agent of the present invention forms a coating film that is applied to the substrate surface to become a liquid crystal alignment film. When the solid concentration is less than 1% by weight, the film thickness of the coating film becomes too small to obtain a good liquid crystal alignment film. When the solid concentration exceeds 10% by weight, the film thickness of the coating film becomes excessively large, and it becomes difficult to obtain a good liquid crystal alignment film, and the viscosity of the liquid crystal aligning agent is increased, and the coating properties are likely to deteriorate.

Particularly preferable ranges of the solid concentration vary depending on the method used when the liquid crystal aligning agent is applied to the substrate. For example, in the case of the spinner method, the range of 1.5 to 4.5 wt% is particularly preferable. In the case of the printing method, it is particularly preferable that the solid concentration is set in the range of 3 to 9 wt%, and accordingly, the solution viscosity is set in the range of 12 to 50 mPa · s. In the case of the ink-jet method, it is particularly preferable that the solid concentration is in the range of 1 to 5 wt%, and the solution viscosity is in the range of 3 to 15 mPa · s accordingly.

The temperature for producing the liquid crystal aligning agent of the present invention is preferably from 0 캜 to 200 캜, more preferably from 20 캜 to 60 캜.

The liquid crystal aligning agent for forming the liquid crystal alignment film of the present invention preferably contains a compound having at least one epoxy group in the molecule (hereinafter also referred to as &quot; epoxy group-containing compound &quot;) from the viewpoint of improving the adhesion to the substrate surface . Examples of the epoxy group-containing compound include 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, Tetraglycidyl-2,4-hexanediol, N, N, N ', N'-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl ) Cyclohexane, N, N, N ', N'-tetraglycidyl-4,4'-diaminodiphenylmethane, and the like. The compounding ratio of these epoxy group-containing compounds is preferably 50 parts by weight or less, more preferably 0.1 to 45 parts by weight, based on 100 parts by weight of the polymer.

The liquid crystal aligning agent of the present invention may also contain a functional silane-containing compound. Examples of such a functional silane-containing compound include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- 2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3- Ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-tri Methoxysilylpropyl triethylenetriamine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl- 3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N- Aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis (oxyethylene) Methoxy silane, N-bis (oxyethylene) -3-aminopropyltriethoxysilane, and the like.

The compounding ratio of these functional silane-containing compounds is preferably 40 parts by weight or less based on 100 parts by weight of the polymer.

<Liquid crystal display element>

The liquid crystal display element obtained by using the liquid crystal aligning agent of the present invention can be produced, for example, by the following method.

(1) The liquid crystal aligning agent of the present invention is applied to one surface of a substrate on which a patterned transparent conductive film is provided by, for example, a roll coater method, a spinner method, a printing method, an inkjet method, etc., Thereby forming a coating film. Examples of the substrate include glass such as float glass and soda glass; A transparent substrate made of plastic such as polyethylene terephthalate, polybutylene terephthalate, polyether sulfone, or polycarbonate can be used. Examples of the transparent conductive film provided on one surface of the substrate include a NESA film (tentatively known as PPG Corporation, USA) containing tin oxide (SnO ₂ ), an ITO film containing indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ) Can be used. For patterning these transparent conductive films, a photoetching method or a method using a mask in advance is used. In the application of the liquid crystal aligning agent, a functional silane-containing compound, a functional titanium-containing compound and the like may be previously applied to the surface of the substrate in order to further improve adhesion between the substrate surface and the transparent conductive film. The heating temperature after application of the liquid crystal aligning agent is, for example, 80 to 300 占 폚, preferably 120 to 250 占 폚. The liquid crystal aligning agent of the present invention containing a polyamic acid can form a coating film to be an orientation film by removing the organic solvent after coating, and further, by heating, the dehydration ring closure can be advanced to form a further imidized coating film. The film thickness of the formed coating film is preferably 0.001 to 1 mu m, more preferably 0.005 to 0.5 mu m.

(2) In some cases, rubbing treatment is performed in which the formed film surface is rubbed in a predetermined direction with a roll covered with a cloth containing fibers such as nylon, rayon, and cotton. Accordingly, the alignment ability of the liquid crystal molecules is imparted to the coating film to form a liquid crystal alignment film.

The liquid crystal alignment layer formed by the liquid crystal aligning agent of the present invention can be obtained by adding ultraviolet rays to the liquid crystal alignment layer formed by the liquid crystal aligning agent of the present invention as described in, for example, Japanese Patent Application Laid-Open Nos. 6-222366 and 6-281937 A process of changing the pre-tilt angle by partial irradiation or a process of forming a resist film partially on the surface of the liquid crystal alignment film subjected to the rubbing treatment as described in Japanese Patent Application Laid-open No. 5-107544, It is possible to improve the clock characteristic of the liquid crystal display element by performing the rubbing treatment in a direction different from that of the liquid crystal display element and then removing the resist film and changing the liquid crystal alignment capability of the liquid crystal alignment film.

(3) Two substrates on which liquid crystal alignment films were formed as described above were prepared, and two substrates were arranged to face each other with a gap (cell gap) interposed therebetween so that the rubbing direction in each liquid crystal alignment film was orthogonal or anti-parallel , The periphery of the two substrates is bonded using a sealant, the liquid crystal is injected and filled in the cell space defined by the surface of the substrate and the sealant, and the injection hole is sealed to constitute the liquid crystal cell. A liquid crystal display element is obtained by disposing a polarizing plate on the outer surface of the liquid crystal cell, that is, on the transparent substrate side constituting the liquid crystal cell.

As the sealing agent, for example, an epoxy resin containing an aluminum oxide sphere as a curing agent and a spacer may be used.

Examples of liquid crystals include nematic liquid crystals and smectic liquid crystals. Among them, a nematic liquid crystal is preferable, and examples thereof include a liquid crystal such as a Shifa salt liquid crystal, an agar liquid crystal, a biphenyl liquid crystal, a phenylcyclohexane liquid crystal, an ester liquid crystal, a terphenyl liquid crystal, a biphenylcyclohexane liquid crystal, Based liquid crystal, a dioxane-based liquid crystal, a bicyclooctane-based liquid crystal, a quartz-based liquid crystal, and the like. Further, cholesteric liquid crystals such as cholesteryl chloride, cholesteryl nonanoate and cholesteryl carbonate, and liquid crystal products such as trade names "C-15" and "CB-15" (manufactured by Merck) And the like can be added to the composition. Further, ferroelectric liquid crystals such as p-disiloxybenzylidene-p-amino-2-methylbutyl cinnamate can also be used.

As a polarizing plate to be bonded to the outer surface of the liquid crystal cell, a polarizing plate having a polarizing film called an H film absorbing iodine and a polarizing plate sandwiched by a cellulose acetate protective film or a polarizing plate including the H film itself .

Hereinafter, the present invention will be described more specifically by way of examples, but the present invention is not limited to these examples. The imidization rate, voltage holding ratio and baking test of the imidized polymer in Examples and Comparative Examples were evaluated by the following methods.

[Method of measuring imidization rate of imidized polymer]

The imidized polymer was dried under reduced pressure at room temperature, dissolved in deuterated dimethyl sulfoxide, and subjected to ¹ H-NMR measurement at room temperature using tetramethylsilane as a reference material, and was determined by the following formula (i).

&Lt; EMI ID =

Imidization rate (%) = (1-A ¹ / A ² × α) × 100

A ¹ : Peak area (10 ppm) derived from proton of NH group

A ² : Peak area derived from other protons

?: the ratio of the number of other proton to one proton of the NH group in the polymer precursor (polyamic acid)

[Voltage maintenance rate]

A voltage of 5 V was applied to the liquid crystal display element with an application time of 60 microseconds and a span of 167 milliseconds, and the voltage maintenance ratio after 167 milliseconds from the application of the voltage was measured. VHR-1 manufactured by Toyo Technica Co., Ltd. was used as a measuring device. The case where the voltage holding ratio was 85% or more was evaluated as good, and the other cases were judged as poor.

[Vertical Orientation Evaluation]

When the liquid crystal display device manufactured by the above method was observed visually from the vertical direction with respect to the liquid crystal display element at the time of applying no voltage under crossed-Nicol and at an AC voltage of 12 V (peak-peak) &Quot; Good &quot; was set when the black display was performed.

[Bake test]

Evaluation of the firing test was made under different conditions in the TN alignment film subjected to the rubbing treatment and the VA alignment film not subjected to the rubbing treatment. Fig. 1 shows the arrangement of electrodes prepared for the bake test. In the case of a TN type liquid crystal display device, a DC voltage of 6 V was applied to the electrode A, and a DC voltage of 0.5 V was applied to the electrode B at room temperature for 24 hours. In the VA type liquid crystal display device, a DC voltage of 5 V was applied to the electrode A, and a DC voltage of 1 V was applied to the electrode B at room temperature for 2 hours. After the stress was released, a DC voltage of 0.1 to 5.0 V was applied to the electrodes A and B at intervals of 0.1 V, and the burning characteristics were determined by the difference in brightness between the electrodes A and B at the respective voltages. It was judged that the burning property was bad when the difference in luminance was large.

Synthesis Example 1

As a tetracarboxylic acid dianhydride, 112.09 g (0.5 mol) of 2,3,5-tricarboxycyclopentylacetic dianhydride and 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- 157.15 g (0.5 mol) of p-phenylenediamine as a diamine compound, 93.54 g (0.865 mol) of p-phenylenediamine as a diamine compound 24.85 g (0.1 mole) of 3,3 '- (tetramethyldisiloxane-1,3-diyl) bis (propylamine) and 12.86 g (0.02 mole) of the diamine represented by the above formula (12) 8.09 g (0.03 mol) of n-octadecylamine was dissolved in 950 g of N-methyl-2-pyrrolidone and reacted at 60 DEG C for 6 hours. A small amount of the obtained polyamic acid solution was collected, NMP was added, and the viscosity of the solution was measured with a solution having a solid concentration of 10% by weight, and found to be 60 mPa · s. To the obtained polyamic acid was added 2,700 g of N-methyl-2-pyrrolidone to dissolve it. 400 g of pyridine and 410 g of acetic anhydride were added, followed by dehydration ring closure at 110 占 폚 for 4 hours. After the imidization reaction, the solvent in the system was replaced with a solvent with a new? -Butyrolactone (in this operation, pyridine and anhydrous acetic acid used in the imidization reaction were removed out of the system), a solid concentration of 10 wt%, a solid concentration of 10 wt% (γ-butyrolactone solution) having a solution viscosity of 55 mPa · s and an imidization ratio of about 93% (hereinafter, referred to as "polymer A-1").

Synthesis Example 2

19.2 g (0.1 mole) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as a tetracarboxylic dianhydride, 3.2 g (0.034 mole) of p-phenylenediamine as a diamine compound, 4,4'-diamino 8.5 g (0.05 mol) of diphenylmethane, 6.7 g (0.015 mol) of the diamine represented by the formula (14) and 0.16 g (0.002 mol) of N-octadecylamine as a monoamine were dissolved in N-methyl- And reacted at 60 DEG C for 4 hours. A small amount of the obtained polyamic acid solution was collected, NMP was added, and the viscosity of the solution was measured with a solution having a solid concentration of 10% by weight, and found to be 85 mPa · s. To the resulting polyamic acid was added 351 g of N-methyl-2-pyrrolidone to dissolve it. 18.6 g of pyridine and 17.6 g of acetic anhydride were added, followed by dehydration cyclization at 110 DEG C for 4 hours. After the imidization reaction, the solvent in the system was replaced with a solvent with a new? -Butyrolactone (in this operation, pyridine and anhydrous acetic acid used in the imidization reaction were removed out of the system), a solid concentration of 10 wt%, a solid concentration of 10 wt% (γ-butyrolactone solution) having a viscosity of 80 mPa · s and an imidization rate of about 86% (hereinafter, referred to as "polymer A-2").

Synthesis Example 3

20.9 g (0.1 mole) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as a tetracarboxylic acid dianhydride, 7.86 g (0.08 mole) of p-phenylenediamine as a diamine compound, (0.02 mol) of diamine was dissolved in 150 g of N-methyl-2-pyrrolidone, and the mixture was reacted at 60 DEG C for 4 hours. A small amount of the obtained polyamic acid solution was collected, NMP was added, and the viscosity of the solution was measured with a solution having a solid concentration of 10% by weight and found to be 120 mPa · s. 320 g of N-methyl-2-pyrrolidone was dissolved in the obtained polyamic acid, and 6.7 g of pyridine and 8.6 g of acetic anhydride were added, followed by dehydration cyclization at 110 DEG C for 4 hours. After the imidization reaction, the solvent in the system was replaced with a new? -Butyrolactone solvent (pyridine and anhydrous acetic acid used in the imidization reaction were removed from the system in this step), and a solid concentration of 10% by weight and a solid concentration of 10% 360 g of an imidized polymer having a solution viscosity of 110 mPa 의 and an imidization rate of about 54% of γ-butyrolactone solution (this is referred to as "polymer A-3") was obtained.

Synthesis Example 4

19.06 g (0.1 mole) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as a tetracarboxylic acid dianhydride, 6.66 g (0.07 mole) of p-phenylenediamine as a diamine compound, 2.22 g (0.01 mol) of the diamine and 9.20 g (0.02 mol) of the diamine represented by the above formula (14) were dissolved in 150 g of N-methyl-2-pyrrolidone and reacted at 60 DEG C for 4 hours. A small amount of the obtained polyamic acid solution was collected, NMP was added, and the viscosity was measured with a solution having a solid concentration of 10% by weight, and it was found to be 70 mPa · s. The obtained polyamic acid was dissolved by addition of 350 g of N-methyl-2-pyrrolidone, and 6.7 g of pyridine and 8.6 g of acetic anhydride were added, followed by dehydration ring closure at 110 DEG C for 4 hours. After the imidization reaction, the solvent in the system was replaced with a solvent with a new? -Butyrolactone (in this operation, pyridine and anhydrous acetic acid used in the imidization reaction were removed out of the system), a solid concentration of 10 wt%, a solid concentration of 10 wt% (γ-butyrolactone solution) having a solution viscosity of 66 mPa · s and an imidization rate of about 54% (this is referred to as "polymer A-4").

Synthesis Example 5

124.36 g (1.0 mole) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride and 140.38 g (1.0 mole) of the diamine represented by the above formula (II-2) as a diamine compound were dissolved in N- Pyrrolidone and reacted at 40 占 폚 for 3 hours. Then 1,150 g of? -Butyrolactone was added to obtain a polyamic acid having a solid content concentration of 10% by weight and a solution viscosity of 60 mPa 占 퐏 (B-1) &quot;) solution (2600 g).

Synthesis Example 6

64.07 g (0.5 mole) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as a tetracarboxylic dianhydride, 56.05 g (0.5 mole) of 1,2,3,4-cyclobutane tetracarboxylic dianhydride, 144.63 g (1.0 mol) of the diamine represented by the above formula (II-2) as a diamine compound was dissolved in 1,500 g of N-methyl-2-pyrrolidone and reacted at 40 DEG C for 3 hours. Then,? -Butyrolactone 1,150 g to obtain about 2,600 g of a polyamic acid solution having a solid concentration of 10% by weight and a solution viscosity of 85 mPa · s (referred to as "polyamic acid (B-2)").

Synthesis Example 7

115.34 g (1.0 mole) of 1,2,3,4-cyclobutane tetracarboxylic dianhydride as a tetracarboxylic dianhydride and 149.41 g (1.0 mole) of a diamine represented by the above formula (II-2) as a diamine compound were dissolved in N -Methyl-2-pyrrolidone and reacted at 40 占 폚 for 3 hours. 1,150 g of? -Butyrolactone was then added thereto to obtain a polyamic acid solution having a solid concentration of 10% by weight and a solution viscosity of 65 mPa 占 퐏 (Hereinafter referred to as &quot; polyamic acid (B-3) &quot;).

Synthesis Example 8

196.11 g (1.0 mole) of 1,2,3,4-cyclobutane tetracarboxylic acid dianhydride as a tetracarboxylic dianhydride and 212.30 g of 2,2'-dimethyl-4,4'-diaminobiphenyl as a diamine compound (1.0 mole) was dissolved in 370 g of N-methyl-2-pyrrolidone and 3,300 g of? -Butyrolactone, and the mixture was reacted at 40 占 폚 for 3 hours to obtain a solution having a solid concentration of 10% by weight and a solution viscosity of 160 mPa.s To obtain about 4,000 g of a solution of polyamic acid (referred to as &quot; polyamic acid (B-4) &quot;).

Synthesis Example 9

As the tetracarboxylic acid dianhydride, 98.05 g (0.50 mol) of 1,2,3,4-cyclobutane tetracarboxylic dianhydride, 109.06 g (0.50 mol) of pyromellitic dianhydride, and 4,4'- 200 mg (1.0 mole) of diaminodiphenyl ether was dissolved in 230 g of N-methyl-2-pyrrolidone and 2,100 g of? -Butyrolactone, and the mixture was reacted at 40 占 폚 for 3 hours. About 2,700 g of a polyamic acid (referred to as &quot; polyamic acid (B-5) &quot;) having a solid concentration of 10% by weight and a solution viscosity of 125 mPa · s was obtained.

Example 1

The imidized polymer (A-1) obtained in Synthesis Example 1 and the polyamic acid (B-1) obtained in Synthesis Example 5 were mixed in the ratio of imidated polymer (A-1): polyamic acid (B- N-methyl-2-pyrrolidone / butyl cellosolve mixed solvent (weight ratio 71/17/12) so as to obtain an epoxy group-containing compound, and N, N, N ', N -Tetraglycidyl-4,4'-diaminodiphenylmethane was dissolved in 2 parts by weight based on 100 parts of the polymer to prepare a solution having a solid content concentration of 3.5% by weight. After sufficiently stirring, the solution was filtered through a filter To obtain a liquid crystal aligning agent of the present invention. The liquid crystal aligning agent was applied (rotation number: 2,500 rpm, application time: 1 minute) onto a transparent conductive film made of an ITO film provided on one side of a glass substrate having a thickness of 1 mm by using a spinner, And dried for a time to form a film having a dry film thickness of 0.08 mu m. The rubbing treatment was carried out by a rubbing machine having a roll having a rayon cloth covered with this coating, at a rotation speed of the roll of 400 rpm, a moving speed of the stage of 3 cm / sec, and a press-fit length of 0.4 mm. The liquid crystal alignment film coated substrate was ultrasonically cleaned in ultrapure water for 1 minute and then dried in a clean oven at 100 DEG C for 10 minutes. Next, an epoxy resin adhesive containing aluminum oxide spheres having a diameter of 5.5 占 퐉 was applied to each of outer edges of the pair of transparent electrode / transparent electrode substrates having the liquid crystal alignment film of the liquid crystal alignment film coated substrate, And the adhesive was cured. Subsequently, a nematic liquid crystal (MLC-6221, manufactured by Merck & Co., Inc.) was filled between the substrates from the liquid crystal injection port, the liquid crystal injection hole was sealed with an acrylic photocurable adhesive, and a polarizing plate was bonded to both sides of the substrate, A display device was manufactured. The voltage holding ratio of the obtained liquid crystal display element was evaluated. The liquid crystal aligning agent obtained in the present invention exhibited a relatively high voltage holding ratio. In addition, after-image evaluation by luminance was performed using two sets of liquid crystal display elements manufactured by the same liquid crystal aligning agent, and a baking test was conducted, and good results were obtained.

Examples 2 to 3 and Comparative Example 1

(A-1) obtained in Synthesis Example 1, the polyamic acid (B-2) obtained in Synthesis Example 6 in Example 2, the polyamic acid (B-3) obtained in Synthesis Example 7 in Example 3, In Example 1, the polyamic acid (B-4) obtained in Synthesis Example 8 and the N, N, N ', N'-tetramethyl-4,4'-diaminodiphenylmethane as the epoxy group- Butyrolactone as a main component to obtain a solution having a solid content concentration of 3.5%, and this solution was filtered with a filter having an opening diameter of 1 탆 to prepare a liquid crystal aligning agent of the present invention. Using each of the liquid crystal aligning agents thus prepared, a film was formed on the surface of the substrate in the same manner as in Example 1, and a liquid crystal display device was produced using the substrate on which the liquid crystal alignment film was formed. Then, the voltage holding ratio was evaluated. A baking test was also conducted. The results are shown in Table 1 below.

Example 4

The imidized polymer (A-2) obtained in Synthesis Example 2 and the polyamic acid (B-1) obtained in Synthesis Example 5 were mixed in the ratio of imidated polymer (A-2): polyamic acid (B- N, N ', N', N'-tetramethyldisiloxane as an epoxy group-containing compound were dissolved in a mixed solution of gamma -butyrolactone / N-methyl-2-pyrrolidone / butyl cellosolve (weight ratio 40/35/25) -Tetraglycidyl-4,4'-diaminodiphenylmethane was dissolved in an amount of 20 parts by weight based on 100 parts by weight of the polymer to obtain a solution having a solid content concentration of 3.5% by weight. This solution was filtered using a filter having a pore size of 1 탆 to prepare a film-forming composition of the present invention.

Next, the composition for film formation was applied on a transparent conductive film made of ITO film provided on one side of a glass substrate having a thickness of 1 mm by a spinner and dried at 200 DEG C for 60 minutes to obtain a film having a dry film thickness of 0.08 mu m .

Next, an epoxy resin adhesive containing an aluminum oxide sphere having a diameter of 3.5 占 퐉 was applied to each of outer edges of the pair of transparent electrode / transparent electrode substrates having the liquid crystal alignment film of the liquid crystal alignment film coated substrate, And the adhesive was cured. Subsequently, a negative type liquid crystal (MLC-6608, manufactured by Merck & Co., Inc.) was charged between the substrates from the liquid crystal injection port, the liquid crystal injection hole was sealed with an acrylic photocurable adhesive, a polarizing plate was bonded to both sides of the substrate, Device. The obtained liquid crystal display element was evaluated for vertical orientation, which was good. Further, the after-image evaluation by luminance was performed using two sets of liquid crystal display elements manufactured by the same liquid crystal aligning agent, and the difference in luminance was small and the "afterimage was good".

Examples 5 to 6 and Comparative Example 2

The imidized polymer (A-2) obtained in Synthesis Example 2, the polyamic acid (B-2) obtained in Synthesis Example 6 in Example 5, the polyamic acid (B-3) obtained in Synthesis Example 7 in Example 6, In Example 2, the polyamic acid (B-5) obtained in Synthesis Example 9 and the N, N, N ', N'-tetramethyldipiperazine-4,4'-diaminodiphenylmethane as the epoxy group- Was dissolved in a mixed solvent mainly composed of butyrolactone to obtain a solution having a solid content concentration of 3.5%, and this solution was filtered with a filter having an opening diameter of 1 탆 to prepare a liquid crystal aligning agent of the present invention. Using each of the liquid crystal aligning agents thus prepared, a film was formed on the surface of the substrate in the same manner as in Example 3, and a liquid crystal display device was produced using the substrate on which the liquid crystal alignment film was formed. Then, the voltage holding ratio was evaluated. A baking test was also conducted.

Example 7 and Comparative Example 3

The imidized polymer (A-4) obtained in Synthesis Example 4 was used in Example 5, the imidized polymer (A-3) obtained in Synthesis Example 3 in Comparative Example 3 and the imidized polymer -Tetraglycidyl-4,4'-diaminodiphenylmethane was dissolved in a solution of N-methyl-2-pyrrolidone / butyl cellosolve (weight ratio 50/50) to obtain a solution having a solid concentration of 3.5% , And this solution was filtered with a filter having an opening diameter of 1 탆 to prepare a liquid crystal aligning agent of the present invention. Using each of the liquid crystal aligning agents thus prepared, a film was formed on the surface of the substrate in the same manner as in Example 3, and a liquid crystal display device was produced using the substrate on which the liquid crystal alignment film was formed. Then, the voltage holding ratio was evaluated and a baking test was also performed. The results are shown in Table 2 below.

1 is an electrode layout diagram prepared for a baking test.

Claims (6)

A polymer comprising at least one repeating unit of an amic acid repeating unit represented by the following formula (I-1) and an imide repeating unit represented by the following formula (I-2), wherein in the one or more repeating units, Q ¹ or Q ² in the formula I-2 is in the first orientation to the liquid crystal, characterized in that the divalent organic group represented by the formula II. <Formula I-1>

(Wherein P ¹ represents a tetravalent organic group constituting a tetracarboxylic acid, and Q ¹ represents a divalent organic group constituting a diamine) &Lt; Formula (I-2) >

(Wherein P ² represents a tetravalent organic group constituting the tetracarboxylic acid, and Q ² represents a divalent organic group constituting the diamine) &Lt;

(Wherein Y represents a single bond or a divalent organic group having 1 to 30 carbon atoms) The method according to claim 1, wherein P ^{1 in the} formula I- ¹ or P ² in the formula I- ² is 1,2,3,4-cyclobutane tetracarboxylic acid dianhydride, 1,3-dimethyl- , 3,4-cyclobutanetetracarboxylic acid dianhydride, 1,2,4,5-cyclohexanetetracarboxylic acid dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 1,3,3a , 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [ 3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3- furanyl) , 3-oxabicyclo [3.2.1] octane-2,4-dione-6-spiro-3 '- (tetrahydrofuran-2', 5'- dione), 3,5,6-tricarboxy- -Carboxy norbornane-2: 3,5: 6-dianhydride, bicyclo [3.3.0] octane-2,4,6,8-tetracarboxylic acid dianhydride and 1,2,3,4- And at least one tetracarboxylic acid dianhydride selected from the group consisting of pentane tetracarboxylic dianhydride Wherein the liquid crystal aligning agent is a tetravalent organic group derived from water. The positive resist composition according to claim 1, wherein the polymer comprises an amic acid repeating unit represented by the formula (I-1) and an imide repeating unit represented by the formula (I-2) Of the liquid crystal alignment agent is 10 mol% or more. The liquid crystal aligning agent according to claim 1, further comprising a compound having at least one epoxy group in the molecule in an amount of not more than 45 parts by weight based on 100 parts by weight of the polymer. A liquid crystal alignment film formed from the liquid crystal aligning agent according to any one of claims 1 to 4. A liquid crystal display element comprising the liquid crystal alignment film according to claim 5.

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