KR101510483B1 - Liquid crystal aligning agent and liquid crystal display device - Google Patents

Abstract

An object of the present invention is to provide a liquid crystal alignment film excellent in liquid crystal alignability and electrical characteristics and capable of providing a liquid crystal alignment film excellent in coating property without foaming at the time of application to a substrate, Lt; / RTI >

Wherein the liquid crystal aligning agent comprises (A) 100 parts by weight of at least one polymer selected from the group consisting of a polyamic acid obtained by reacting a tetracarboxylic dianhydride with a diamine and an imidized polymer thereof, and

(B) 0.01 to 100 parts by weight of a specific epoxy compound represented by the following formula.

A liquid crystal aligning agent, a liquid crystal display element, a tetracarboxylic dianhydride, a polyamic acid, an imidized polymer

Description

TECHNICAL FIELD [0001] The present invention relates to a liquid crystal aligning agent and a liquid crystal display element,

The present invention relates to a liquid crystal aligning agent and a liquid crystal display element. More particularly, the present invention relates to a liquid crystal aligning agent having excellent printability and a liquid crystal display element obtained therefrom.

As a liquid crystal display element, a liquid crystal alignment layer is formed on the surface of a substrate on which a transparent conductive film is provided to form a substrate for a liquid crystal display element. Two liquid crystal alignment layers are disposed opposite to each other, and a nematic liquid crystal layer having positive dielectric anisotropy TN type liquid crystal display device having so-called TN type (Twisted Nematic) liquid crystal cell in which the long axis of the liquid crystal molecules is made to be a cell of a sandwich structure and is twisted by 90 degrees continuously from one substrate toward the other substrate is widely known. In addition, an STN (Super Twisted Nematic) type liquid crystal display device which can realize a high contrast ratio compared to a TN type liquid crystal display device, an IPS (In-Plane Switching) type liquid crystal display device with little visual dependency, An optical compensation bend (OCB) type liquid crystal display device having a small display dependency and excellent high-speed responsiveness of an image screen has been developed (see Patent Documents 1 to 5 below).

As a material of the liquid crystal alignment film in these liquid crystal display elements, a resin material such as polyamic acid, polyimide, polyamide, and polyester is known. Particularly, a liquid crystal alignment film containing polyamic acid or polyimide has heat resistance, mechanical strength, (For example, see Patent Documents 6 to 8 below).

Attempts have been made to add a silane coupling agent to such a liquid crystal aligning agent in order to improve the uniformity of the film thickness of the formed coating film, in particular, the film thickness at the center of the substrate and the uniformity of the film thickness at the end portions 9). However, in the liquid crystal aligning agent to which the silane coupling agent is added, the uniformity of the film thickness of the formed coating film is improved, but the foaming is liable to occur during application of the liquid crystal aligning agent, and this foam becomes a pinhole of the liquid crystal alignment film, And the like are damaged.

 A liquid crystal aligning agent capable of providing a liquid crystal alignment film excellent in heat resistance and having no foaming at the time of application and having excellent printability and sufficient film thickness uniformity of the formed film has not been known.

[Patent Document 1] Japanese Unexamined Patent Publication No. 2002-62537

[Patent Document 2] Japanese Unexamined Patent Application Publication No. 7-261181

[Patent Document 3] Japanese Unexamined Patent Publication No. 2003-107486

[Patent Document 4] JP-A-11-258605

[Patent Document 5] Japanese Patent Application Laid-Open No. 2007-9031

[Patent Document 6] JP-A-9-197411

[Patent Document 7] Japanese Unexamined Patent Publication No. 2003-149648

[Patent Document 8] Japanese Unexamined Patent Publication No. 2003-107486

[Patent Document 9] Japanese Unexamined Patent Publication (Kokai) No. 62-243917

[Patent Document 10] JP-A-6-222366

[Patent Document 11] Japanese Unexamined Patent Application Publication No. 6-281937

[Patent Document 12] JP-A-5-107544

An object of the present invention is to provide a liquid crystal alignment film which is excellent in liquid crystal alignability and electrical characteristics and which can provide a liquid crystal alignment film which does not generate bubbles at the time of application to a substrate and has good application properties, And to provide an alignment agent.

It is another object of the present invention to provide a liquid crystal display element provided with a liquid crystal alignment film having no pinhole and excellent in liquid crystal alignability.

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

According to the present invention, the above objects and advantages of the present invention are achieved by firstly,

(A) 100 parts by weight of at least one polymer selected from the group consisting of a polyamic acid obtained by reacting a tetracarboxylic dianhydride with a diamine and an imidized polymer thereof, and

(B) 0.01 to 100 parts by weight of at least one compound selected from the group consisting of a compound represented by the following formula (1) and a compound represented by the following formula (hereinafter referred to as "epoxy compound (B)")

And a liquid crystal aligning agent.

[화학식 R^I-2]

(In the formula 1, a is 2, R ^I is represented by the following giim, or a phenylene group, the formula R ^I R ^I -1 or -2)
Formula ^I R -1]

[Chemical formula R ^I -2]

(A group of formula (II), R ^II are each a hydrocarbon group having 1 to 12 carbon atoms, which may be the same each present a plurality of R ^II that are or different, p is an integer from 1 to 3, q is an integer of 1 to 20)

According to the present invention, it is possible to provide a liquid crystal alignment film having excellent liquid crystal alignment properties and electrical characteristics, and also to provide a liquid crystal alignment film which does not generate bubbles at the time of application to the substrate and has good applicability and does not cause pinholes or unevenness in printing , A liquid crystal aligning agent having a uniform film thickness uniformity is provided.

The liquid crystal display element of the present invention including the liquid crystal alignment layer formed of such a liquid crystal aligning agent can be suitably used for TN type and STN type liquid crystal display elements and can be used in various types such as SH type, Bend (OCB) type, ferroelectric and antiferroelectric liquid crystal display devices, and the like. The liquid crystal display element of the present invention can be effectively used in various apparatuses and is preferably used for display devices such as a desk calculator, a wristwatch, a desk clock, a coefficient display board, a word processor, a personal computer, a liquid crystal television and the like.

In the liquid crystal display element of the present invention,

(A) 100 parts by weight of at least one polymer selected from the group consisting of a polyamic acid obtained by reacting a tetracarboxylic dianhydride with a diamine and an imidized polymer thereof (hereinafter referred to as "(A) polymer"),

(B) 0.01 to 100 parts by weight of at least one compound selected from the group consisting of the compound represented by the formula (1) and the compound represented by the formula (2) (hereinafter referred to as the "epoxy compound (B)

Lt; / RTI >

Hereinafter, the present invention will be described in detail.

<(A) Polymer>

The polymer (A) contained in the liquid crystal aligning agent of the present invention is at least one selected from the group consisting of a polyamic acid obtained by reacting a tetracarboxylic dianhydride with a diamine and an imidized polymer thereof.

[Polyamic acid]

The polyamic acid can be synthesized by reacting a tetracarboxylic dianhydride with a diamine.

- tetracarboxylic dianhydride -

Examples of the tetracarboxylic acid dianhydride used for synthesizing the polyamic acid include butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic acid 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-cyclobutane tetracarboxylic acid dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutane tetracarboxylic acid dianhydride, 1,2,3,4- Cyclopentanetetracarboxylic acid dianhydride, 1,2,4,5-cyclohexanetetracarboxylic acid dianhydride, 3,3 ', 4,4'-dicyclohexyltetracarboxylic acid dianhydride, 2,3,4- 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-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2- c] Dione, 1,3,3a, 4,5,9b-hexahydro-5-methyl-5 (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [ -1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5-ethyl-5- (tetrahydro-2,5-dioxo-3-furanyl) 2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-7-methyl-5- (tetrahydro- -Naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-7-ethyl-5- (tetrahydro- 3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro- 1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-ethyl- (Tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2- c] -furan- 1,3 -dione, 1,3,3a, 4,5,9b- hexa (Tetrahydro-2,5-dioxo-3-furanyl) -naphtho [l, 2-c] 5-di Cyclohexene-1,2-dicarboxylic acid anhydride, bicyclo [2,2,2] -oct-7-ene-2,3,5,6-tetrahydro- Tetra-carboxylic acid dianhydride, 3-oxabicyclo [3.2.1] octane-2,4-dione-6-spiro-3 '- (tetrahydrofuran-2', 5'- , 5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride, 3,5,6-tricarboxy-2-carboxynorbornane- : 3,5: 6-dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] undecane-3,5,8,10-tetraone, each of TI and T-II Aliphatic and alicyclic tetracarboxylic acid dianhydrides such as compounds to be displayed;

[Chemical formula I-I]

[Chemical Formula T-II]

(In the formulas TI and T-II, R ¹ and R ³ each represent a divalent organic group having an aromatic ring, R ² and R ⁴ each represent a hydrogen atom or an alkyl group, and R ² and R ⁴ , Which may be the same or different)

Pyromellitic dianhydride, 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-biphenylsulfonetetracarboxylic acid dianhydride, 1,4,5 , 8-naphthalene tetracarboxylic acid dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3 ', 4,4'-biphenyl ether tetracarboxylic dianhydride, 3,3 ', 4,4'-dimethyldiphenylsilane tetracarboxylic dianhydride, 3,3', 4,4'-tetraphenylsilane tetracarboxylic dianhydride, 1,2,3,4-furan tetracarboxyl Acid dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylsulfide dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylsulfone dianhydride, 4 , 4'-bis (3,4-dicarboxyphenoxy) diphenylpropane dianhydride, 3,3 ', 4,4'-perfluoroisopropylidene diphthalic acid dianhydride, 3,3' '-Biphenyltetracarboxylic dianhydride, 2,2', 3,3'-biphenyltetracarboxylic dianhydride, bis (phthalic acid) phenylphosphine oxide dianhydride (triphenylphthalic acid) dianhydride, bis (triphenylphthalic acid) -4,4'-diphenyl ether dianhydride, bis (triphenylphthalic acid) dianhydride, m-phenylene- Triphenylphthalic acid) -4,4'-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 -Bis (anhydrotrimellitate), compounds represented by each of the following formulas (T-1) to (T-4), and the like. These may be used singly or in combination of two or more.

[Chemical formula (T-1)

[Chemical Formula T-2]

[Chemical Formula T-3]

[Chemical Formula T-4]

The tetracarboxylic acid dianhydride used for synthesizing the polyamic acid contained in the liquid crystal aligning agent of the present invention is preferably selected from butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic acid dianhydride, 1,2,3,4-cyclopentanetetracarboxylic acid dianhydride, 2,3,5-tricarboxycyclopentyl Acetic acid dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [ , 3-dione, 1, 3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5,8-dimethyl-5- (tetrahydro-2,5-dioxo-3-furanyl) 1,2-c] furan-1,3-dione, bicyclo [2,2,2] -oct-7-ene-2,3,5,6-tetracarboxylic acid dianhydride, 3- Spiro-3 '- (tetrahydrofuran-2', 5'-dione), 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride, 3,5,6-tricarboxy-2-carboxy norbornane -2: 3,5: 6-dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] undecane-3,5,8,10-tetraone, pyromellitic acid dianhydride, 3 , 3 ', 4,4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-biphenylsulfonetetracarboxylic acid dianhydride, 2,2 ', 3,3'-biphenyl Tetra-carboxylic acid dianhydride, 1,4,5,8-naphthalenetetracarboxylic acid dianhydride, a compound represented by the following formula (T-5) to (T-7) (Hereinafter referred to as "specific tetracarboxylic dianhydride (1)") selected from the group consisting of compounds represented by the following general formula (T-8) among the compounds represented by the general formula From the viewpoint of exhibiting this good liquid crystal alignment property, Preferable.

[Chemical Formula T-5]

[Chemical Formula T-6]

[Chemical Formula T-7]

[Chemical Formula T-8]

Specific examples of the tetracarboxylic dianhydride (1) include 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 1,3,3a, (Tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a , 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [ 3-oxabicyclo [3.2.1] octane-2,4-dione-6-spiro-3 '- (tetrahydrofuran-2', 5'- dione), 5- (2,5-dioxotetrahydro 3-cyclohexene-1,2-dicarboxylic acid anhydride, 3,5,6-tricarboxy-2-carboxy norbornane-2: 3,5: 6- Dianhydride, dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] undecane-3,5,8,10-tetraone, pyromellitic dianhydride and the compound represented by the above formula (T-5) Is preferable.

The tetracarboxylic acid dianhydride used for synthesizing the polyamic acid contained in the liquid crystal aligning agent of the present invention is obtained by reacting the specific tetracarboxylic dianhydride (1) as described above with the tetracarboxylic dianhydride Is preferably at least 5 mol%, more preferably at least 10 mol%, and even more preferably at least 30 mol%, based on the whole amount. By using the tetracarboxylic acid dianhydride containing the specific tetracarboxylic dianhydride (1) in the range as described above, it is possible to synthesize a polyamic acid having a higher solubility in an organic solvent to be described later, The liquid crystal aligning agent containing the liquid crystal aligning agent is preferable because it can set the kind and composition of the organic solvent to be used in a wide range and has an advantage of a great degree of freedom in product design.

 - diamine -

Examples of the diamine used for synthesizing the polyamic acid contained in the liquid crystal aligning agent of the present invention include p-phenylenediamine, m-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4 ' -Diaminodiphenylethane, 4,4'-diaminodiphenylsulfide, 4,4'-diaminodiphenylsulfone, 3,3'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diaminodiphenylsulfone, '-Diaminobenzanilide, 4,4'-diaminodiphenyl ether, 1,5-diaminonaphthalene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl- 4,4'-diaminobiphenyl, 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl, 3,3'-ditrifluoromethyl-4,4'-diaminobis Phenyl, 1,3,3-trimethyl indane, 3,3-trimethyl indane, 6-amino-1- (4'-aminophenyl) Diaminobenzophenone, 4,4'-diaminobenzophenone, 2,2-bis [4- (4-tert-butylphenyl) Aminophenoxy) phenyl] propane, 2,2-bis [4- (4- Bis (4-aminophenoxy) phenyl] sulfone, 1,4-bis (4-aminophenoxy) phenyl] hexafluoropropane, 2,2- Benzene, 1,3-bis (4-aminophenoxy) benzene, 9,9-bis (4-aminophenoxy) benzene, Diaminofluorene, 9,9-dimethyl-2,7-diaminofluorene, 9,9-bis (4-aminophenyl) fluorene, 4,4'-methylene -Bis (2-chloroaniline), 2,2 ', 5,5'-tetrachloro-4,4'-diaminobiphenyl, 2,2'-dichloro-4,4'- Dimethoxybiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 1,4,4 '- (p-phenyleneisopropylidene) bisaniline, 4,4' - m-phenylene isopropylidene) bisaniline, 2,2'-bis [4- (4-amino-2-trifluoromethylphenoxy) phenyl] hexafluoropropane, 4,4'- , 2'-bis (trifluoromethyl) biphenyl, 4,4'-bis [(4-amino-2-trifluoromethyl) During; - octafluoro lobby aromatic diamine, such as phenyl;

But are not limited to, 1,1-hexanediol diamine, 1,1-meta-xylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, , 1,4-diaminocyclohexane, isophoronediamine, tetrahydrodicyclopentadienylenediamine, hexahydro-4,7-methanoindenyldimethylenediamine, tricyclo [6.2.1.0 ^2,7 ] undecylene Aliphatic or alicyclic diamines such as dimethyldiamine, 4,4'-methylenebis (cyclohexylamine), 1,3-bis (aminomethyl) cyclohexane and 1,4-bis (aminomethyl) cyclohexane;

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, Aminophenyl) phenylamine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, N-ethyl- Aminocarbazole, N-phenyl-3,6-diaminocarbazole, N, N'-di (4-aminophenyl) -benzidine, and a compound represented by the following formula DI, A diamine having two primary amino groups in the molecule and a nitrogen atom other than the primary amino group;

[Formula D-I]

(In the formula DI, R ⁵ represents a monovalent organic group having a ring structure including a nitrogen atom selected from pyridine, pyrimidine, triazine, piperidine and piperazine, and X ¹ represents a divalent organic group)

[Formula D-II]

(Wherein R ⁶ represents a divalent organic group having a cyclic structure including a nitrogen atom selected from pyridine, pyrimidine, triazine, piperidine and piperazine, each of X ² represents a divalent organic group, A plurality of X &lt; ² &gt; s present may be the same or different)

Mono-substituted phenylenediamines such as a compound represented by the following formula (D-III);

[Formula D-III]

(In the formula (D-III), R ⁷ represents a divalent organic group selected from -O-, -COO-, -OCO-, -NHCO-, -CONH- and -CO-, R ⁸ represents a steroid skeleton, A monovalent organic group having a skeleton or a group selected from a methylphenyl group, a trifluoromethoxyphenyl group and a fluorophenyl group, or an alkyl group having 6 to 30 carbon atoms)

A diaminoorganosiloxane represented by the following formula (D-IV);

[Formula D-IV]

(In the formula (D-IV), R ⁹ represents a hydrocarbon group of 1 to 12 carbon atoms, plural R ^{9 s} present may be the same or different, r is an integer of 1 to 3, and s is an integer of 1 to 20 Integer)

And compounds represented by the following formulas (D-1) to (D-5). These diamines may be used alone or in combination of two or more.

[Formula D-1]

[Formula D-2]

[Formula D-3]

[Formula D-4]

[Formula D-5]

(Y in the formula (D-4) is an integer of 2 to 12, and z in the formula (D-5) is an integer of 1 to 5)

The diamine used for synthesizing the polyamic acid contained in the liquid crystal aligning agent of the present invention is preferably one selected from the group consisting of p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl Sulfide, 1,5-diaminonaphthalene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl, 2 , 4,4'-diaminodiphenyl ether, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 9,9- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 4,4 '- Isopropylidene) bisaniline, 4,4 '- (m-phenylene diisopropylidene) bisaniline, 1,4-bis (4-aminophenoxy) benzene, 4,4'- Biphenyl, 1,4-cyclohexanediamine, 4,4'-methylenebis (cyclohexylamine), 1,3-bis (aminomethyl) cyclohexane, -5, a compound represented by the following general formula (1), a compound represented by the general formula (2): 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminoacridine, N-methyl-3,6-diaminocarbazole, N-ethyl-3,6-diaminocarbazole, N-phenyl- ) -Benzidine, a compound represented by the following formula D-6 in the compound represented by the formula DI above, a compound represented by the following formula D-7 in the compound represented by the formula D-II, Among the compounds, dodecaneoxy-2,4-diaminobenzene, pentadecaneoxy-2,4-diaminobenzene, hexadecaneoxy-2,4-diaminobenzene, octadecanoxy- 2,5-diaminobenzene, octadecaneoxy-2,5-diaminobenzene, hexadecaneoxy-2,5-diaminobenzene, octadecanoxy-2,5-diaminobenzene, The compounds represented by D-8 to D-16 and the compounds represented by the formulas (Hereinafter referred to as "specific diamine (1)") selected from the group consisting of 1,3-bis (3-aminopropyl) -tetramethyldisiloxane among the compounds represented by the general formula (D-IV) .

[Formula D-6]

[Formula D-7]

[Formula D-8]

[Chemical formula D-9]

[Formula D-10]

[Formula D-11]

[Formula D-12]

[Formula D-13]

[Chemical Formula D-14]

[Formula D-15]

[Formula D-16]

The diamine used for synthesizing the polyamic acid contained in the liquid crystal aligning agent of the present invention is preferably at least 0.5 mol% based on the total amount of the tetracarboxylic acid dianhydride to be used, More preferably 1 mol% or more, and still more preferably 3 mol% or more. By using a diamine containing the specific diamine (1) in the range as described above, it is possible to synthesize a polyamic acid having a higher solubility in an organic solvent, which will be described later. Therefore, the liquid crystal aligning agent containing the diamine It is possible to set the kind and the composition of the organic solvent to a wide range, which is advantageous in that the degree of freedom of product design is increased, which is preferable.

- Synthesis of polyamic acid -

The ratio of the tetracarboxylic dianhydride and the diamine compound used in the synthesis reaction of the polyamic acid is preferably 0.5 to 2 equivalents of the acid anhydride group of the tetracarboxylic dianhydride relative to 1 equivalent of the amino group contained in the diamine compound , And more preferably 0.7 to 1.2 equivalents.

The synthesis reaction of the polyamic acid is carried out in an organic solvent under a temperature condition of preferably -20 to 150 ° C, more preferably 0 to 100 ° C, preferably 1 to 24 hours, more preferably 1 to 16 hours Time. 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, Non-protonic polar solvents such as dimethyl sulfoxide,? -Butyrolactone, tetramethyl urea, and hexamethylphosphoric triamide; m-cresol, xylenol, phenol, halogenated phenol and the like. 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.

Alcohol, ketone, ester, ether, halogenated hydrocarbon, hydrocarbon, etc., which are poor solvents of polyamic acid, may be added to the organic solvent in such a range that the produced polyamic acid is not precipitated. 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, But are not limited to, butyl lactate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl acetate, ethyl acetate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, diethyl oxalate, 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, Ethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene Recycled monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, tetrahydrofuran, dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, o -Dichlorobenzene, hexane, heptane, octane, benzene, toluene, xylene, isoamyl propionate, isoamyl isobutyrate, and diisopentyl ether.

When the organic solvent and the poor solvent as described above are used in combination, the amount of the poor solvent to be used is preferably 50% by weight or less, more preferably 20% by weight or less, particularly 5% by weight or less based on the total amount of the solvent desirable.

In this way, a reaction solution obtained by dissolving polyamic acid is obtained. The reaction solution may be used as it is for preparing a liquid crystal aligning agent. Alternatively, the polyamic acid contained in the reaction solution may be isolated and used for the preparation of a liquid crystal aligning agent, or after the isolated polyamic acid is purified, . The isolation of the polyamic acid can be carried out by pouring the reaction solution into a large amount of a poor solvent to obtain a precipitate, drying the precipitate under reduced pressure, or a method of distilling off the reaction solution under reduced pressure using an evaporator. Alternatively, the polyamic acid can be purified by a method of dissolving the polyamic acid in an organic solvent, followed by precipitation with a poor solvent, or a step of distillation under reduced pressure using an evaporator once or several times.

[Imidized polymer]

The imidized polymer used in the present invention can be synthesized by dehydrating and ring closure of a polyamic acid obtained by reacting a tetracarboxylic acid dianhydride and a diamine.

- tetracarboxylic dianhydride -

Examples of the tetracarboxylic acid dianhydride used for synthesizing the imidized polymer include the same compounds as the tetracarboxylic dianhydride used in the synthesis of the above-mentioned polyamic acid.

The tetracarboxylic acid dianhydride used for synthesizing the imidized polymer preferably contains an alicyclic tetracarboxylic acid dianhydride (hereinafter referred to as "specific tetracarboxylic dianhydride (2)"). Specific examples of the specific tetracarboxylic dianhydride (2) include 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro- 3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- ( Furanyl) -naphtho [1,2-c] furan-1,3-dione, 3-oxabicyclo [3.2.1] octane- (Tetrahydrofuran-2 ', 5'-dione), 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene- Dicarboxylic acid anhydride, 3,5,6-tricarboxy- ^2- carboxynorbornane-2: 3,5: 6-dianhydride and 4,9-dioxatricyclo [5.3.1.0 ^{2, 6} ] undecane-3,5,8,10-tetraone.

The tetracarboxylic acid dianhydride used for synthesizing the imidized polymer which may be contained in the liquid crystal aligning agent of the present invention is preferably a tetracarboxylic dianhydride (2) using the specific tetracarboxylic dianhydride (2) Preferably 5 mol% or more, more preferably 10 mol% or more, and still more preferably 30 mol% or more based on the total amount of water. By using the tetracarboxylic acid dianhydride containing the specific tetracarboxylic dianhydride (2) in the range as described above, it becomes possible to synthesize an imidized polymer having better solubility in an organic solvent described later, Therefore, the liquid crystal aligning agent containing the liquid crystal aligning agent can be set in a wide range in the kind and composition of the organic solvent to be used, which is advantageous in that the degree of freedom of product design is increased, which is preferable.

- diamine -

Examples of the diamine used for synthesizing the imidized polymer include the same diamine as the diamine used in the synthesis of the polyamic acid described above.

The diamine used for synthesizing the imidized polymer preferably contains a diamine represented by the above formula (D-III) (hereinafter referred to as "specific diamine (2)"). Specific examples of the diamine (2) include dodecaneoxy-2,4-diaminobenzene, pentadecaneoxy-2,4-diaminobenzene, hexadecaneoxy- 4-diaminobenzene, dodecaneoxy-2,5-diaminobenzene, pentadecaneoxy-2,5-diaminobenzene, hexadecaneoxy-2,5-diaminobenzene, octadecanoxy- At least one member selected from the group consisting of diaminobenzene and the compounds represented by the above formulas D-8 to D-16.

As the diamine used for synthesizing the imidized polymer, the specific diamine (2) may be used alone, or a specific diamine (2) may be used in combination with other diamines. Examples of such other diamines include diamines used in the synthesis of polyamic acid, other than the compounds represented by the above formula (D-III), and among them, p-phenylenediamine, 4,4'- Phenylmethane, 4,4'-diaminodiphenylsulfide, 1,5-diaminonaphthalene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-ditrifluoromethyl 4,4'-diaminobiphenyl, 2,7-diaminofluorene, 4,4'-diaminodiphenyl ether, 2,2-bis [4- (4-aminophenoxy) phenyl] Bis (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoro Propane, 4,4 '- (p-phenylenediisopropylidene) bisaniline, 4,4' - (m-phenylenediisopropylidene) bisaniline, 1,4-cyclohexanediamine, Bis (cyclohexylamine), 1,4-bis (4-aminophenoxy) benzene, 4,4'-bis Phenyl, compounds represented by the above formulas D-1 to D-5, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminoacridine, N, N'-dimethyl-benzidine, a compound represented by the formula (D-2) in the compound represented by the formula (DI) (3-aminopropyl) -tetramethyl (3-aminopropyl) tetramethylammonium chloride in the compound represented by Formula D-7 and the compound represented by Formula D-IV in the compound represented by Formula D- And disiloxane.

The diamine used for synthesizing the imidized polymer contained in the liquid crystal aligning agent of the present invention is preferably such that the specific diamine (2) as described above is used in an amount of preferably 0.5 mol% or more, Is at least 1 mol%, more preferably at least 3 mol%. By using a diamine containing the specific diamine (2) in the range as described above, it is possible to synthesize an imidized polymer having a higher solubility in an organic solvent, which will be described later. Therefore, the liquid crystal aligning agent containing the diamine It is possible to set the kind and the composition of the organic solvent to a wide range, which is advantageous in that the degree of freedom of product design is increased, which is preferable.

- Synthesis of imidized polymer -

The imidized polymer contained in the liquid crystal aligning agent of the present invention may be a completely imidized polymer in which all of the amic acid units contained in the polyamic acid as the precursor are dehydrated and cyclized or the amidic acid unit and the dehydrated and cyclized imide ring coexist It may be a partial imide cargo. The imidization rate of the imidized polymer is preferably 40% or more, and more preferably 80% or more. Here, the "imidization rate" is a percentage of the number of imide rings relative to the sum of the number of amide structures and the number of imide rings in the polymer. At this time, a part of the imide ring may be an isoimide ring. The imidization ratio is determined by dissolving polyimide in a suitable deuterated solvent (for example, deuterated dimethyl sulfoxide) and measuring tetramethylsilane as a reference material at room temperature by ¹ H-NMR, Can be obtained.

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

(A ¹ is the peak area derived from the proton of the NH group near 10 ppm of the chemical shift, A ² is the peak area derived from the other protons, and? Is the peak area derived from the polyimide precursor (polyamic acid) The ratio of the number of other proton to one proton of the NH group)

The imidized polymer contained in the liquid crystal aligning agent of the present invention is obtained by dehydrating and ring closure of the polyamic acid. The dehydration ring closure of 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 does not proceed sufficiently, and if the reaction temperature exceeds 200 ° C, the molecular weight of the resulting imidized polymer may be lowered. The reaction time is preferably 1 to 12 hours, more preferably 1 to 6 hours.

On the other hand, in the method of adding the dehydrating agent and the dehydrating ring-closing catalyst to the solution of the polyamic acid of the above (ii), an acid anhydride such as acetic anhydride, propionic acid 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 thereto. 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 to be used. Examples of the organic solvent used in the dehydration ring-closure reaction include organic solvents exemplified for use in the synthesis of polyamic acid. The reaction temperature for the dehydration ring closure reaction is preferably 0 to 180 ° C, more preferably 10 to 150 ° C, and the reaction time is preferably 1 to 12 hours, more preferably 1 to 6 hours.

In the above method (ii), a reaction solution is obtained as described above. In the production of the liquid crystal aligning agent of the present invention, this reaction solution may be used as it is for the production of a liquid crystal aligning agent, the dehydrating agent and the dehydration ring-closing catalyst may be removed from the reaction solution and then used for preparing a liquid crystal aligning agent, It may be used in the production of a liquid crystal aligning agent after isolation, or may be used in the production of a liquid crystal aligning agent after purification of the isolated polyimide. In order to remove the dehydrating agent and the dehydration ring-closing catalyst from the reaction solution, for example, a method such as solvent substitution can be applied. Isolation and purification of the polyimide can be carried out by carrying out the same operations as the isolation and purification of the polyamic acid.

[Polymer of terminal modified type]

The polyamic acid and the imidized polymer may be of a terminally modified type having a controlled molecular weight. Such a terminal modification type can be synthesized by adding a molecular weight regulator to the reaction system when synthesizing polyamic acid. Examples of the molecular weight regulator include acid monoanhydride, monoamine compound, monoisocyanate compound and the like.

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.

The molecular weight modifier is preferably used in an amount of 10 parts by weight or less, more preferably 5 parts by weight or less, based on 100 parts by weight of the total amount of the tetracarboxylic acid dianhydride and diamine used for synthesizing the polyamic acid.

[Solution viscosity]

The polyamic acid or polyimide thus obtained preferably has a solution viscosity of 20 to 800 mPa 으로 when it is a 10 wt% solution, more preferably a solution viscosity of 30 to 500 mPa 바람직 Do.

The solution viscosity (mPa 占 퐏) of the polymer is determined by using a polymer (e.g.,? -Butyrolactone, N-methyl-2-pyrrolidone or the like) Solution was measured at 25 캜 using an E-type rotational viscometer.

&Lt; Epoxy Compound (B) >

The epoxy compound (B) contained in the liquid crystal aligning agent of the present invention is at least one compound selected from the group consisting of the compound represented by the formula (1) and the compound represented by the formula (2).

In formula (1), a is 2.

The group R ^I in the above formula (1) is a phenylene group or a group represented by the formula R ^I -1 or R ^I -2. Examples of the compound represented by the formula (1) include compounds represented by the following formulas (1-2) to (1-3).

[Formula 1-2]

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[Formula 1-3]

As R ^II in the above formula (2), for example, a methyl group, an ethyl group, a propyl group or a phenyl group is preferable. p is preferably 3, and q is preferably an integer of 1 to 10, more preferably an integer of 1 to 3, and still more preferably 1. Specific examples of the compound represented by the formula (2) include compounds represented by the following formula (2-1).

[Formula 2-1]

In the liquid crystal aligning agent of the present invention, the use ratio of at least one compound selected from the group consisting of the compound represented by the formula (1) and the compound represented by the formula (2) is 100 wt% of the polyamic acid and the imidized polymer 0.01 to 100 parts by weight based on 100 parts by weight of the resin. This value is preferably 0.01 to 40 parts by weight, more preferably 0.01 to 30 parts by weight, particularly preferably 0.1 to 20 parts by weight. By using the epoxy compound (B) in such a ratio, the liquid crystal aligning agent of the present invention is preferable because it can exhibit the advantage that the coating property is good and the film thickness uniformity of the formed coating film is excellent.

In the liquid crystal aligning agent of the present invention, a part of the epoxy compound (B) may be substituted by a compound having at least one epoxy group in the molecule other than the epoxy compound (B) (hereinafter referred to as "other epoxy compound"). Examples of such other epoxy compounds include, for example, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl Ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3, 5,6-tetraglycidyl-2,4-hexanediol, N, N, -diglycidyl-benzylamine and N, N-diglycidyl-aminomethylcyclohexane.

When a part of the epoxy compound (B) is used in place of the other epoxy compound in the liquid crystal aligning agent of the present invention, the proportion of the other epoxy compound to be used is preferably 40 (%) based on the total amount of the epoxy compound (B) By weight or less, more preferably 30% by weight or less, and preferably 20% by weight or less.

By using the epoxy compound (B) and, if necessary, other epoxy compounds at such a ratio, the effect of improving the coating property of the liquid crystal aligning agent of the present invention can be expected. In addition, when the liquid crystal aligning agent of the present invention is applied to a substrate, There is no problem.

<Other ingredients>

The liquid crystal aligning agent of the present invention contains the above-mentioned (A) polymer and the epoxy compound (B).

The liquid crystal aligning agent of the present invention may further contain other components in addition to the polymer (A) and the epoxy compound (B) as long as the effect of the present invention is not impaired. Examples of such other components include a functional silane compound and the like.

Examples of the functional silane compound include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2 -Aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltri 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- Aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis (oxyethylene) -3-aminopropyltrimethoxysilane, N-bis (oxyethylene) -3-aminopropyltriethoxysilane and the like.

The blending ratio of the functional silane compound is preferably 2 parts by weight or less, more preferably 0.2 parts by weight, per 100 parts by weight of the (A) polymer.

<Liquid Crystal Aligner>

The liquid crystal aligning agent of the present invention is constituted by dissolving and containing the above-mentioned polymer (A), the epoxy compound (B) and optionally other optional components as required, in an organic solvent.

Examples of the organic solvent usable in the liquid crystal aligning agent of the present invention include N-methyl-2-pyrrolidone,? -Butyrolactone,? -Butyrolactam, N, N-dimethylformamide, N, N -Dimethyl acetamide, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethyleneglycol methyl ether , Ethylene glycol ethyl ether, ethylene glycol n-propyl ether, ethylene glycol-i-propyl ether, ethylene glycol-n-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, Dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, Diisobutyl ketone, isoamyl propionate, isoamyl isobutyrate, and diisopentyl ether. These may be used alone or in combination of two or more.

The solid concentration in the liquid crystal aligning agent of the present invention (the ratio of the total weight of the components other than the liquid crystal aligning agent to the total weight of the liquid crystal aligning agent) is appropriately selected in consideration of viscosity, volatility, etc., By weight. That is, the liquid crystal aligning agent of the present invention is applied to the surface of the substrate as described later, and preferably, when heated, forms a coating film which becomes a liquid crystal alignment film. However, when the solid concentration is less than 1% by weight, On the other hand, when the solid concentration exceeds 10% by weight, the film thickness of the coating film becomes excessively large and a good liquid crystal alignment film can not be obtained, the viscosity of the liquid crystal aligning agent is increased and the coating property is lowered do.

Particularly preferable ranges of the solid concentration are different 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 solid content concentration is particularly preferably in the range of 1.5 to 4.5 wt%. In the case of the printing method, it is particularly preferable that the solid concentration is in the range of 3 to 9 wt%, and the solution viscosity is accordingly 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 0 to 200 占 폚, more preferably 20 to 60 占 폚.

<Liquid crystal display element>

The liquid crystal display element of the present invention comprises the liquid crystal alignment layer formed of the liquid crystal aligning agent of the present invention as described above.

The liquid crystal display element of the present invention can be produced, for example, by the following steps (1) to (3).

(1) The liquid crystal aligning agent of the present invention is applied to one side of a substrate on which a patterned transparent conductive film is provided by an appropriate application method such as offset printing, spin coating, or inkjet printing, Thereby forming a coating film. Examples of the substrate include glass such as float glass and soda glass; A transparent substrate containing plastic such as polyethylene terephthalate, polybutylene terephthalate, polyether sulfone, polycarbonate, and alicyclic polyolefin can be used. Examples of the transparent conductive film provided on one side of the substrate include a NESA film (a registered trademark of PPG Corporation of the US) and indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ) containing tin oxide (SnO ₂ ) An ITO film or the like can be used. For patterning these transparent conductive films, a photo etching method or a method of using a mask in advance when forming a transparent conductive film is used. When applying the liquid crystal aligning agent, a functional silane compound, a functional titanium compound or 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 and the coating film. After the application of the liquid crystal aligning agent, preliminary heating (prebaking) is preferably performed first for the purpose of preventing the applied alignment agent from being dropped. The prebaking temperature is preferably 30 to 200 ° C, more preferably 40 to 150 ° C, and particularly preferably 40 to 100 ° C. The prebaking time is preferably 0.1 to 10 minutes, more preferably 0.5 to 5 minutes. Further, it is preferable that after the solvent is completely removed, a further heating (post-baking) step is performed. The post-baking temperature is preferably 80 to 300 占 폚, more preferably 120 to 250 占 폚. The post baking time is preferably 1 to 90 minutes, and more preferably 5 to 60 minutes. The liquid crystal aligning agent of the present invention forms a coating film which becomes an alignment film by removing the organic solvent after coating as described above. When the amic acid structure remains in the polymer (A) contained in the liquid crystal aligning agent of the present invention , A dehydration ring-closure reaction may be further promoted by further heating after forming a coating film to make a more imaged 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) The coating film formed as described above can be used as it is as a vertically aligned liquid crystal alignment film. Alternatively, a coating film made of a suitable fiber such as nylon, rayon, And then used as a liquid crystal alignment film. The coating film after the rubbing treatment can be also applied to the coating film described in Patent Document 10 (Japanese Patent Application Laid-Open No. 6-222366) or Patent Document 11 (Japanese Patent Application Laid-Open No. 6-281937) A process of changing the pretilt angle of a part of the liquid crystal alignment film by irradiating a part of the same liquid crystal alignment film with ultraviolet rays and a process of changing the pretilt angle of a part of the liquid crystal alignment film surface as described in Patent Document 12 (Japanese Patent Application Laid-open No. 5-107544) A rubbing process is performed in a direction different from the rubbing process performed previously and then the resist film is removed so that the liquid crystal alignment film has different liquid crystal aligning ability for each region so that the visual characteristics of the obtained liquid crystal display device can be obtained It is possible to improve.

(3) In the case where two substrates on which the liquid crystal alignment film is formed as described above are rubbed, the two substrates are spaced apart by a gap (cell interval) so that the rubbing direction in each liquid crystal alignment film is orthogonal or inverted And the liquid crystal is injected and filled in the cell space defined by the surface of the substrate and the sealing agent and the injection hole is sealed to constitute the liquid crystal cell. Further, the liquid crystal display element of the present invention can be manufactured by bonding a polarizing plate to the outer surface of the liquid crystal cell, that is, the outside of each substrate 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 can be used. Examples of the liquid crystal include a nematic liquid crystal and a smectic liquid crystal. Among them, a nematic liquid crystal is preferable. For example, a liquid crystal such as a salt liquid crystal, an agar liquid crystal, a biphenyl liquid crystal, a phenylcyclohexane liquid crystal, , Terphenyl-based liquid crystals, biphenylcyclohexane-based liquid crystals, pyrimidine-based liquid crystals, dioxane-based liquid crystals, bicyclooctane-based liquid crystals, quaternary-based liquid crystals and the like. Examples of the liquid crystal include cholesteric liquid crystals such as cholestyl chloride, cholesteryl nonoate and cholesteryl carbonate; Chiral agents such as those sold under the trade names "C-15" and "CB-15" (manufactured by Merck); p-disiloxybenzylidene-p-amino-2-methylbutyl cinnamate, or the like may be added to the composition.

As the polarizing plate to be bonded to the outer surface of the liquid crystal cell, a polarizing plate in which a polarizing film called "H film " in which iodine is absorbed while polyvinyl alcohol is oriented in a stretched polyvinyl alcohol is sandwiched between cellulose acetate protective films or a polarizing plate made of H film itself can be given.

<Examples>

Hereinafter, the present invention will be described more specifically by way of examples, but the present invention is not limited to these examples.

The imidation rate of the imidized polymer in the above Examples and Comparative Examples was measured by a method in which the imidated polymer was thoroughly dried at room temperature under reduced pressure and then dissolved in deuterated dimethyl sulfoxide and tetramethylsilane was used as a reference material and ¹ H Was calculated from the -NMR spectrum according to the above formula (1).

The solution viscosity of the polymer solution was measured at 25 캜 using an E-type rotational viscometer.

Synthesis Example 1

109 g (0.50 mol) of pyromellitic dianhydride as tetracarboxylic dianhydride and 98 g (0.50 mol) of 1,2,3,4-cyclobutane tetracarboxylic dianhydride as a diamine compound, 4,4-diamine 200 g (1.0 mole) of minodiphenyl ether was dissolved in a mixed solvent containing 244 g of N-methyl-2-pyrrolidone and 2,200 g of? -Butyrolactone and reacted at 40 占 폚 for 3 hours, -Butyrolactone was added to obtain about 4,070 g of a solution containing 10 wt% of polyamic acid (A-1). The solution viscosity of this solution was 200 mPa..

Synthesis Example 2

98 g (0.50 mol) of 1,2,3,4-cyclobutane tetracarboxylic dianhydride and 109 g (0.50 mol) of pyromellitic dianhydride as a tetracarboxylic dianhydride and 4,4'- 198 g (1.0 mole) of diaminodiphenylmethane was dissolved in a mixed solvent containing 243 g of N-methyl-2-pyrrolidone and 2,190 g of? -Butyrolactone and reacted at 40 占 폚 for 3 hours, 1,210 g of? -butyrolactone was added to obtain about 4,050 g of a solution containing 10 wt% of polyamic acid (A-2). The solution viscosity of this solution was 125 mPa s.

Synthesis Example 3

196 g (1.0 mole) of 1,2,3,4-cyclobutane tetracarboxylic dianhydride as tetracarboxylic dianhydride and 200 g (1.0 mole) of 4,4'-diaminodiphenyl ether as a diamine compound 238 g of N-methyl-2-pyrrolidone and 2,130 g of? -Butyrolactone, reacted at 40 占 폚 for 4 hours, and then 1,190 g of? -Butyrolactone was added to obtain a polyamic acid About 3,960 g of a solution containing 10% by weight of (A-3) was obtained. The solution viscosity of this solution was 210 mPa s.

Synthesis Example 4

196 g (1.0 mole) of 1,2,3,4-cyclobutane tetracarboxylic dianhydride as a tetracarboxylic dianhydride and 2,2'-dimethyl-4,4'-diaminobiphenyl 212 (A-4) was obtained by dissolving the polyamic acid (A-4) in a mixed solvent containing 367 g of N-methyl-2-pyrrolidone and 3,300 g of? -butyrolactone and reacting at 40 占 폚 for 3 hours. To obtain about 4,080 g of a solution containing 10% by weight. The solution viscosity of this solution was 160 mPa..

Synthesis Example 5

224 g (1.0 mole) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride and 200 g (1.0 mole) of 4,4'-diaminodiphenyl ether as a diamine compound were dissolved in N-methyl -2-pyrrolidone and 2,290 g of? -Butyrolactone, and reacted at 40 占 폚 for 4 hours to obtain about 2,970 g of a solution containing 15% by weight of polyamic acid (A-5) &Lt; / RTI &gt; A small amount of this solution was collected, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight by adding? -Butyrolactone was 38 mPa 占 퐏.

Synthesis Example 6

20 g (0.10 mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride and 196 g (0.90 mol) of pyromellitic dianhydride as a tetracarboxylic dianhydride and 4,4'- 160 g (0.8 mol) of diaminodiphenyl ether and 22 g (0.2 mol) of p-phenylenediamine were dissolved in 3,250 g of N-methyl-2-pyrrolidone and reacted at 40 DEG C for 4 hours to obtain polyamic acid About 3,580 g of a solution containing 11% by weight of (A-6). A small amount of this solution was collected, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight by adding N-methyl-2-pyrrolidone was 200 mPa..

Synthesis Example 7

40 g (0.20 mol) of 1,2,3,4-cyclobutane tetracarboxylic dianhydride and 174 g (0.80 mol) of pyromellitic dianhydride as a tetracarboxylic dianhydride, 2,2'- 170 g (0.8 mole) of dimethyl-4,4'-diaminobiphenyl and 22 g (0.2 mole) of p-phenylenediamine were dissolved in 3,310 g of N-methyl-2-pyrrolidone, To obtain about 3,720 g of a solution containing 11% by weight of polyamic acid (A-7). A small amount of this solution was collected, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight by adding N-methyl-2-pyrrolidone was 160 mPa.s.

Synthesis Example 8

112 g (0.50 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as a tetracarboxylic acid dianhydride and 1,3-dihydroxy-8-methyl-5- 157 g (0.50 mole) of p-phenylenediamine as a diamine compound and 95 g (0.50 mole) of p-phenylenediamine as a diamine compound 32 g (0.10 mol) of 2,2-ditrifluoromethyl-4,4-diaminobiphenyl, 3,6-bis (4-aminobenzoyloxy) cholestane 6.4 g (0.010 mol) of the compound represented by the formula (1) and 4.0 g (0.015 mol) of octadecanoxy-2,5-diaminobenzene were dissolved in 960 g of N-methyl- For 9 hours to obtain a solution containing polyamic acid. A small amount of the obtained polyamic acid solution was fractionated and the solution viscosity was measured as a solution having a polyamic acid concentration of 10% by weight by adding N-methyl-2-pyrrolidone was 58 mPa.s.

2,740 g of N-methyl-2-pyrrolidone, 396 g of pyridine and 409 g of acetic anhydride were added to the obtained polyamic acid solution, and the dehydration ring-closure reaction was carried out at 110 DEG C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a new? -Butyrolactone solvent (by removing pyridine and acetic anhydride used in this dehydration ring-closure reaction from the system), an imidized polymer having an imidization rate of about 95% B-1) in an amount of 15% by weight. A small amount of this solution was collected, and the solution viscosity measured as a solution having an imidation polymer concentration of 10% by weight by adding? -Butyrolactone was 69 mPa 占 퐏.

Synthesis Example 9

112 g (0.50 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as a tetracarboxylic acid dianhydride and 1,3-dihydroxy-8-methyl-5- 157 g (0.50 mole) of p-phenylenediamine, 96 g (0.89 mole) of p-phenylenediamine as a diamine compound (0.10 mole) of bisaminopropyltetramethyldisiloxane and 13 g (0.020 mole) of 3,6-bis (4-aminobenzoyloxy) cholestane, 8.1 g of N-octadecylamine as a monoamine ) Was dissolved in 1,165 g of N-methyl-2-pyrrolidone and reacted at 60 DEG C for 6 hours to obtain a solution containing polyamic acid. A small amount of the obtained polyamic acid solution was fractionated and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight by adding N-methyl-2-pyrrolidone was 60 mPa.s.

Next, 1,165 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, and 396 g of pyridine and 409 g of acetic anhydride were added, followed by dehydration ring closure reaction at 110 DEG C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a new? -Butyrolactone solvent (by removing pyridine and acetic anhydride used in this dehydration ring-closure reaction from the system), an imidized polymer having an imidization rate of about 95% B-2) was obtained in an amount of about 2,710 g. A small amount of this solution was collected, and the solution viscosity measured as a solution having an imidation polymer concentration of 10% by weight by adding? -Butyrolactone was 70 mPa 占 퐏.

Synthesis Example 10

224 g (1.0 mole) of 2,3,5-tricarboxycyclopentylacetic dianhydride as tetracarboxylic dianhydride, 107 g (0.99 mole) of p-phenylenediamine as a diamine compound, and 3,6-bis Aminobenzoyloxy) cholestane were dissolved in 2,024 g of N-methyl-2-pyrrolidone and reacted at 60 占 폚 for 6 hours to obtain a polyamic acid solution having a solution viscosity of about 260 mPa 占 퐏.

Next, 1,012 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, and 396 g of pyridine and 306 g of acetic anhydride were added, followed by dehydration ring closure reaction at 110 占 폚 for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a new? -Butyrolactone solvent (pyridine and acetic anhydride used in this dehydration ring-closure reaction were removed from the system by this operation) to obtain an imidized polymer having an imidization rate of about 89% B-3) in an amount of 10% by weight. The solution viscosity of this solution was 300 mPa..

Synthesis Example 11

112 g (0.50 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as a tetracarboxylic dianhydride and 13 g (0.50 mol) of 1,3,3a, 4,5,9b-hexahydro-8- 157 g (0.50 mole) of p-phenylenediamine as a diamine compound, 89 g (0.82 mole) of p-phenylenediamine as a diamine compound, 32 g (0.10 mol) of 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl, 1- (3,5-diaminobenzoyloxy) -4- 25 g (0.059 mol) of octadecanoxy-2,5-diaminobenzene (0.011 mol) were added to a solution of N- Methyl-2-pyrrolidone, and reacted at 60 DEG C for 6 hours to obtain a solution containing polyamic acid. The solution viscosity of this polyamic acid solution measured as a solution having a polyamic acid concentration of 10 wt% by adding a small amount of the solution and adding N-methyl-2-pyrrolidone was 110 mPa..

1,500 g of the resulting polyamic acid solution was added, and 3,000 g of N-methyl-2-pyrrolidone was added thereto. 221 g of pyridine and 228 g of acetic anhydride were added and the dehydration ring-closure reaction was carried out at 110 DEG C for 4 hours . After the dehydration ring closure reaction, the solvent in the system was replaced with a new? -Butyrolactone solvent (pyridine and acetic anhydride used in this dehydration ring-closure reaction were removed from the system by this operation) to obtain an imidized polymer having an imidization rate of about 92% B-4) was obtained. The solution viscosity of this solution was 130 mPa s.

Synthesis Example 12

224 g (1.0 mole) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic acid dianhydride and 86 g (0.8 mole) of p-phenylenediamine as a diamine compound, 104 g (0.20 mol) of the compound was dissolved in 1,860 g of N-methyl-2-pyrrolidone and reacted at 60 DEG C for 4 hours to obtain a polyamic acid solution having a solution viscosity of about 400 mPa.s.

Then, 1,860 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, and 78 g of pyridine and 101 g of acetic anhydride were added, followed by dehydration ring-closure reaction at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with fresh N-methyl-2-pyrrolidone (pyridine and acetic anhydride used in the dehydration ring closure reaction were removed from the system by this operation) to obtain an imidization rate of about 50% About 4,120 g of a solution containing 10% by weight of the imidized polymer (B-5) was obtained. The solution viscosity of this solution was 50 mPa s.

Synthesis Example 13

224 g (1.0 mole) of 2,3,5-tricarboxycyclopentylacetic dianhydride as a tetracarboxylic acid dianhydride and 97 g (0.9 mole) of p-phenylenediamine as a diamine compound, 53 g (0.10 mol) of the compound was dissolved in 1,690 g of N-methyl-2-pyrrolidone and reacted at 60 DEG C for 4 hours to obtain a polyamic acid solution having a solution viscosity of about 450 mPa.s.

Subsequently, 1,690 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, and 78 g of pyridine and 101 g of acetic anhydride were added and the dehydration ring-closure reaction was carried out at 110 DEG C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with fresh N-methyl-2-pyrrolidone (pyridine and acetic anhydride used in the dehydration ring closure reaction were removed from the system by this operation) to obtain an imidization rate of about 50% About 3,720 g of a solution containing 10% by weight of the imidized polymer (B-6) was obtained. The solution viscosity of this solution was 70 mPa s.

Synthesis Example 14

224 g (1.00 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 86 g (0.80 mol) of p-phenylenediamine as a diamine compound, 4,4'-diaminodi 20 g (0.10 mol) of phenylmethane and 32 g (0.10 mol) of 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl were dissolved in 2,170 g of N-methyl-2-pyrrolidone , And reacted at 60 占 폚 for 6 hours to obtain a polyamic acid solution having a solution viscosity of about 50 mPa 占 퐏.

Next, 1,090 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 158 g of pyridine and 204 g of acetic anhydride were added, and the dehydration ring-closure reaction was carried out at 110 DEG C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with fresh N-methyl-2-pyrrolidone (pyridine and acetic anhydride used in the dehydration ring closure reaction were removed from the system by this operation) to obtain an imidization rate of about 75% About 3,590 g of a solution containing 10% by weight of the imidized polymer (B-7) was obtained. The solution viscosity of this solution was 60 mPa..

Synthesis Example 15

220 g (1.00 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride, 76 g (0.70 mol) of p-phenylenediamine as a diamine compound, 4,4'- 40 g (0.2 mol) of phenylmethane and 52 g (0.10 mol) of 3 (3,5-diaminobenzoyloxy) cholestane were dissolved in 1560 g of NMP and reacted at 60 DEG C for 6 hours. A small amount of the obtained polyamic acid solution was collected, and NMP was added thereto to measure the viscosity of the solution with a solid concentration of 10%. The viscosity was 60 mPa 占 퐏. Then, 3600 g of NMP was added to the obtained polyamic acid solution, and 80 g of pyridine and 100 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 (by this operation, pyridine and acetic anhydride used in the imidization reaction were removed out of the system), a solid content concentration of 15 wt%, a solid content concentration of 10% About 5550 g of a solution of the imidized polymer ("imidized polymer (B-8)") having a solution viscosity of 87 mPa 揃 s and an imidization rate of about 80% at the time of the reaction (γ-butyrolactone solution)

Example 1

A solution containing the imidized polymer (B-1) obtained in Synthesis Example 8 was converted into an imidized polymer in an amount corresponding to 100 parts by weight, and an epoxy compound (B) 5 parts by weight of the compound was further added to the solvent composition BL: NMP: BC = N-methyl-2-pyrrolidone (NMP) and butyl cellosolve (BC) 71: 17: 12 (weight ratio) and a solid content concentration of 4% by weight, and this solution was filtered using a filter having an opening diameter of 1 占 퐉 to prepare a liquid crystal aligning agent.

The liquid crystal aligning agent was evaluated by the following method. The evaluation results are shown in Table 1 below.

(1) Evaluation of printability

The liquid crystal aligning agent prepared above was applied to a glass substrate with a transparent electrode containing an ITO film by a printing method using the liquid crystal alignment film printing machine (manufactured by Nippon Shashin Inks Co., Ltd.) under the following conditions.

Orienting agent Dispense amount: 3.0 mL / min

Coating speed: 30 m / min

Nip pressure: 0.20 mm

Subsequently, the coated substrate was prebaked at 80 DEG C for 1 minute, and then baked at 200 DEG C for 60 minutes to form a coating film on the substrate. This coating film was visually observed to evaluate printability "good" when neither cratering nor coating unevenness was observed, and " poor printability "when at least one of cratering and coating unevenness was observed.

(2) Evaluation of Film Thickness Uniformity of Coating Film

With respect to the coating film formed above, the film thickness at the center of the substrate and the film thickness at the position near the center of 15 mm from the outer side of the substrate were measured using an erosion-type film thickness meter (manufactured by KLA Tencor Corporation). Film thickness uniformity was evaluated as "good" when the film thickness difference was 20 angstrom or less, and film thickness uniformity was " defective " when the film thickness difference was more than 20 angstrom.

(3) Production of liquid crystal cell

The liquid crystal aligning agent prepared above was applied to a transparent electrode surface of a glass substrate with a transparent electrode including an ITO film using a liquid crystal alignment film printing machine (manufactured by Nippon Sha Shingen Co., Ltd.) After the solvent was removed by heating (prebaking), the coated film was heated on a hot plate at 200 ° C for 10 minutes (post baking) to form a coating film having an average film thickness of 600 Å.

The coating film was subjected to a rubbing treatment with a rubbing machine having a roll wound with a rayon cloth at a roll rotation speed of 500 rpm, a stage moving speed of 3 cm / sec and a piercing length of 0.4 mm to give a liquid crystal aligning ability. Thereafter, ultrasonic cleaning was performed for 1 minute in ultrapure water, and then the substrate was dried in a 100 占 폚 clean oven for 10 minutes to obtain a substrate having a liquid crystal alignment film. This operation was repeated to obtain a pair of substrates (two substrates) each having a liquid crystal alignment film.

Subsequently, epoxy resin adhesive containing aluminum oxide spheres having a diameter of 5.5 占 퐉 was applied to each of the outer edges of the pair of substrates having the liquid crystal alignment film, and then the liquid crystal alignment film surface was superimposed and pressed so as to face the adhesive. Subsequently, a nematic liquid crystal (MLC-6221, manufactured by Merck & Co., Inc.) was filled between the pair of substrates from the liquid crystal injection port, and then the liquid crystal injection hole was sealed with an acrylic light curing adhesive to manufacture a liquid crystal cell.

(4) Evaluation of liquid crystal orientation

When the applied voltage to the liquid crystal cell prepared above was gradually changed from AC 0 to 8 V, both of the vertical direction and the oblique direction of the liquid crystal cell were observed with the naked eye, The case where the liquid crystal orientation was uniformly displayed was evaluated as "good ", and the case where display unevenness was observed in one or both of the viewing directions was evaluated as " poor"

(5) Evaluation of heat resistance stability

A rectangular wave of 30 Hz and 3.0 V, in which an alternating current of 6.0 V (peak-peak) was superposed, was applied to the liquid crystal cell prepared above at an environmental temperature of 70 DEG C for 500 hours. When the cell after 500 hours passed was observed with naked eyes, the case where the display defect was not observed was evaluated as "good heat stability", and the case where the display defect was observed was evaluated as "poor".

Examples 2 to 22 and Comparative Examples 1 to 5

In the same manner as in Example 1 except that the solution containing the polymer used in the production of the liquid crystal aligning agent and the type, amount and solvent composition of the epoxy compound (B) were changed as shown in Table 1, A liquid crystal cell was prepared and evaluated. In Examples 7 to 12 and Comparative Example 2, a nematic liquid crystal "MLC-6608" manufactured by Merck & Co., Inc. was used as a liquid crystal and no rubbing treatment was performed in the formation of a liquid crystal alignment film. Further, in Comparative Examples 1 to 4, the epoxy compound (B) was not used.

The evaluation results are shown in Table 1.

The names of the polymers in Table 1 correspond to the polyamic acid or imidized polymer synthesized in Synthesis Examples 1 to 14, respectively. These polymers are all used for preparing a liquid crystal aligning agent as a polymer solution, and the values in parentheses attached to the polymers in Table 1 are the amounts (parts by weight) of the polymers contained in the polymer solutions used in the respective Examples and Comparative Examples. In Examples 12 to 22 and Comparative Examples 3 and 4, two polymers were used.

Among the names of epoxy compounds (B), (1-2) to (1-3) and (2-1) correspond to the compounds represented by formulas 1-2 to 1-3 and 2-1, respectively . The numerical values in parentheses attached to the names of the epoxy compounds (B) are the amounts (parts by weight) of the epoxy compounds (B) used in the respective Examples.

The abbreviations of the column of the solvent composition mean respectively, and the composition of the solvent is the weight ratio.

BL:? -Butyrolactone

NMP: N-methyl-2-pyrrolidone

BC: butyl cellosolve

Claims (2)

(A) 100 parts by weight of at least one polymer selected from the group consisting of a polyamic acid obtained by reacting a tetracarboxylic dianhydride with a diamine and an imidized polymer thereof, and (B) 0.01 to 100 parts by weight of at least one compound selected from the group consisting of a compound represented by the following formula (1) and a compound represented by the following formula (2) Wherein the liquid crystal aligning agent is a liquid crystal aligning agent. &Lt; Formula 1 >

(In the formula 1, a is 2, R ^I is represented by the following giim, or a phenylene group, the formula R ^I R ^I -1 or -2) Formula ^I R -1]

[Chemical formula R ^I -2]

(2)

(A group of formula (II), R ^II are each a hydrocarbon group having 1 to 12 carbon atoms, which may be the same each present a plurality of R ^II that are or different, p is an integer from 1 to 3, q is an integer of 1 to 20) A liquid crystal display element comprising a liquid crystal alignment film formed of the liquid crystal alignment agent according to claim 1.