KR101536008B1 - Liquid crystal aligning agent and liquid crystal display device - Google Patents

Abstract

An object of the present invention is to provide a liquid crystal aligning agent capable of providing a liquid crystal alignment film excellent in heat resistance and free of bubbles at the time of application and having excellent printability and sufficient film thickness uniformity of the formed film will be.

Wherein the liquid crystal aligning agent comprises at least one polymer selected from the group consisting of a polyamic acid obtained by reacting a tetracarboxylic acid with a diamine including a compound represented by the following Formula 1 and a polyimide obtained by dehydration cyclization of the polyamic acid do.

(Wherein R < 1 & gt ^; and R < ^II & gt ^; are each independently an alkyl group having 1 to 30 carbon atoms)

A liquid crystal aligning agent, a tetracarboxylic acid, a polyamic acid, a polyimide

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 which provides a liquid crystal alignment film excellent in printability and heat resistance and a liquid crystal display element capable of high-quality display, suppressed display deterioration due to thermal stress, and can be driven for a long time.

At present, as a liquid crystal display element, a liquid crystal alignment film 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, and two liquid crystal alignment films are disposed opposite to each other, and a nematic liquid crystal layer TN type liquid crystal display devices having so-called TN type (Twisted Nematic) liquid crystal cells in which the longitudinal axes of the liquid crystal molecules are twisted by 90 degrees continuously from one substrate toward the other substrate are widely known . In addition, STN (Super Twisted Nematic) type liquid crystal display device or IPS (In-Plane Switching) type liquid crystal display device which can realize a higher contrast ratio than the TN type liquid crystal display device, (Fringe Field Switching) type liquid crystal display device and a VA (Vertical Alignment) type liquid crystal display device which improves the brightness by increasing the aperture ratio of the display element portion and the OCB Compensated Bend) type liquid crystal display devices have been developed.

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, And has been used in many liquid crystal display elements (see, for example, Patent Documents 1 to 3 below).

In such a liquid crystal aligning agent, an attempt has been made to add a silane coupling agent for the purpose of improving the uniformity of the film thickness of the formed coating film, in particular, the film thickness at the central portion of the substrate and the uniformity of the film thickness at the end portion (See Patent Document 4 below). However, the liquid crystal aligning agent to which the silane coupling agent is added improves the film thickness uniformity of the coating film to be formed. However, bubbles are liable to be generated during application of the liquid crystal aligning agent, and this foam becomes a pinhole of the liquid crystal alignment film, There is a problem in that it is 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] JP-A-9-197411

[Patent Document 2] Japanese Unexamined Patent Publication No. 2003-149648

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

[Patent Document 4] JP-A-61-171762

[Patent Document 5] JP-A-6-222366

[Patent Document 6] JP-A-6-281937

[Patent Document 7] JP-A-5-107544

It is an object of the present invention to provide a liquid crystal alignment film having excellent heat resistance, and to provide a liquid crystal alignment film excellent in printability without foaming at the time of coating, And to provide a liquid crystal aligning agent having sufficient properties.

It is another object of the present invention to provide a liquid crystal display element which can display a high-quality image and does not deteriorate display performance even when driven for a long period of time.

It is still another object of the present invention to provide a polymer capable of obtaining a liquid crystal aligning agent having the aforementioned advantages and a compound as a raw material thereof.

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

According to the present invention, said object of the present invention is firstly,

A liquid crystal alignment film containing at least one polymer selected from the group consisting of a polyamic acid obtained by reacting a tetracarboxylic dianhydride and a diamine containing a compound represented by the following formula 1 and a polyimide obtained by dehydration cyclization of the polyamic acid ≪ / RTI >

≪ Formula 1 >

(Wherein R < 1 & gt ^; and R < ^II & gt ^; are each independently an alkyl group having 1 to 30 carbon atoms)

The above object of the present invention is secondly,

And a liquid crystal alignment film formed of the above-mentioned liquid crystal aligning agent.

The above object of the present invention is, thirdly,

A polyamic acid obtained by reacting a tetracarboxylic acid dianhydride with a diamine containing a compound represented by the formula (1) or a polyimide obtained by dehydrocondylating the polyamic acid.

The above object of the present invention is, fourthly,

Is achieved by the compound represented by the above-mentioned formula (1).

The liquid crystal aligning agent of the present invention can form a liquid crystal alignment film which does not deteriorate liquid crystal aligning ability even when thermal stress is applied for a long time. The liquid crystal alignment film formed of the liquid crystal aligning agent of the present invention can be suitably applied to various liquid crystal display devices such as TN type, STN type, IPS type, FFS type, VA type, OCB type, ferroelectricity and antiferroelectricity.

The liquid crystal display element of the present invention having such a liquid crystal alignment film is capable of high-quality display, and display performance is not deteriorated even when driven for a long period of time. Therefore, the liquid crystal display device of the present invention can be effectively applied to various devices, and can be applied to various devices such as a clock, a portable game machine, a word processor, a notebook computer, a car navigation system, a camcorder, a portable information terminal, Monitors, and liquid crystal televisions.

Hereinafter, the present invention will be described in detail.

The liquid crystal aligning agent of the present invention comprises a polyamic acid obtained by reacting a tetracarboxylic acid dianhydride with a diamine containing a compound represented by the formula 1 and a polyimide obtained by dehydration cyclization of the polyamic acid Contain at least two polymers.

[Tetracarboxylic acid dianhydride]

Examples of the tetracarboxylic acid dianhydride used for synthesizing the polyamic acid contained in the liquid crystal aligning agent of the present invention include butane tetracarboxylic acid 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'-dicyclohexyltetarboxylic acid Acid dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 3,5,6-tricarboxy norbornane-2-acetic acid dianhydride, 2,3,4,5-tetrahydrofuran tetracarboxyl Acid dianhydride, 1,3,3a, 4,5,9b-hex (Tetrahydro-2,5-dioxo-3-furanyl) -naphtho [l, 2-c] Methyl-5 (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2- c] -furan-1,3-dione, 1,3,3a , 4,5,9b-hexahydro-5-ethyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [ , 1,3,3a, 4,5,9b-hexahydro-7-methyl-5- (tetrahydro-2,5-dioxo-3- furanyl) -naphtho [ -1,3-dione,

1,3,3a, 4,5,9b-hexahydro-7-ethyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [ 1,3-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-8-ethyl-5- (tetrahydro-2,5-dioxo-3-furanyl) 1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5,8-dimethyl-5- (tetrahydro- (2,5-dioxotetrahydrofuranyl) -3-methyl-3-furanyl) -naphtho [1,2-c] 1,2-dicarboxylic acid anhydride, bicyclo [2.2.2] -oct-7-ene-2,3,5,6-tetracarboxylic acid dianhydride, 3-oxabicyclo [3.2.1] (Tetrahydrofuran-2 ', 5'-dione), 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl- 3-cyclohexene-1,2-dicarboxylic acid anhydride, 3,5,6-tricarboxy-2-carboxynorbornane-2: [5.3.1.0 ^2,6] undecane -3,5,8,10- tetrahydro-one, to an aliphatic or alicyclic tetracarboxylic acid dianhydride of the compound and the like represented by the general formula of TI and T-II;

[Chemical formula I-I]

[Chemical Formula T-II]

(Wherein R ¹ and R ³ are each a divalent organic group having an aromatic ring, R ² and R ⁴ are each a hydrogen atom or an alkyl group, and the plural R ² and R ^{4 present} 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- (Anhydrotrimellitate), propylene glycol-bis (anhydrotrimellitate), 1,4-butanediol-bis (anhydroglycidyl) Bis (4-hydroxyphenyl) propane-1,6-hexanediol-bis (anhydrotrimellitate) Aromatic tetracarboxylic dianhydrides such as bis (anhydrotrimellitate) and compounds represented by the following formulas (T-1) to (T-4). 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 acid 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- Tricarboxycyclopentylacetic acid dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [ ] Furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) 1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5,8-dimethyl-5- (tetrahydro- Furanyl) -naphtho [l, 2-c] furan-l, 3-dione, bicyclo [2.2.2] -oct-7-ene-2,3,5,6-tetracarboxylic acid dianhydride, 3-oxabicyclo [3.2.1] octane-2,4-dione-6-spiro-3 '- (tetrahydro Furan-2 ', 5'-dione), 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride, 5,6-tricarboxy-2-carboxynorbornane-2: 3,5: 6-dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] undecane- 3,3 ', 4,4'-benzophenone tetracarboxylic acid dianhydride, 3,3', 4,4'-biphenylsulfonetetracarboxylic dianhydride, 3,3 ', 4,4'-biphenylsulfonetetracarboxylic dianhydride, 2,2 ', 3,3'-biphenyltetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic acid dianhydride, and compounds represented by the above formula (TI) -7 and at least one compound selected from the group consisting of compounds represented by the following formulas (T-8) among the compounds represented by the above formula (T-II) (hereinafter referred to as "specific tetracarboxylic acid dianhydride"Lt; / RTI > is a tetracarboxylic acid dianhydride, preferably < RTI ID = 0.0 > The more preferable in that it can express viewpoints.

[Chemical Formula T-5]

[Chemical Formula T-6]

[Chemical Formula T-7]

[Chemical Formula T-8]

Specific examples of the tetracarboxylic acid dianhydride include 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 1,3,3a, 4,5 , 9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [ 5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [ (Tetrahydrofuran-2 ', 5'-dione), 5- (2,5-dioxotetrahydro-3- 3-cyclohexene-1,2-dicarboxylic acid anhydride, 3,5,6-tricarboxy-2-carboxynorbornane-2: 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) Or more.

As the tetracarboxylic acid dianhydride used for synthesizing the polyamic acid contained in the liquid crystal aligning agent of the present invention, it is preferable that the above specific tetracarboxylic acid dianhydride is contained in an amount of not less than 50 mol% based on the total tetracarboxylic acid dianhydride , And particularly preferably 80 mol% or more.

[Diamine]

The diamine used for synthesizing the polyamic acid contained in the liquid crystal aligning agent of the present invention includes the compound represented by the above formula (1). As the carbon number of alkyl group of 1 to 30 R ^I in the above-mentioned formula (I), having 1 to 10 carbon atoms is a linear or branched alkyl group or an alkyl group branched with a carbon number of 11 to 30 on the ground preferably of the alkyl group of a straight chain of 1 to 10 carbon atoms Or a branched alkyl group having from 11 to 30 carbon atoms. Specific examples of the straight chain alkyl group having 1 to 10 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl and decyl groups. Examples of the branched alkyl group having from 11 to 30 carbon atoms include a 1-methyldodecyl group, a 1-methyltetradecyl group and a 1-methylhexadecyl group.

Specific examples of the compound represented by the formula (1) include N, N-dihexyl-1,2,4-phenyllithriamine, N, N-dioctyl- N, N-bis (1-methyltetradecyl) -1,2,4-phenylenetriamine, etc., .

As the diamine for synthesizing the polyamic acid contained in the liquid crystal aligning agent of the present invention, only the compound represented by the formula (1) may be used alone, or the compound represented by the formula (1) may be used in combination with other diamines.

Examples of other diamines usable in the present invention include p-phenylenediamine, m-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylethane, '-Diaminodiphenylsulfide, 4,4'-diaminodiphenylsulfone, 3,3'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diaminobenzanilide, Diaminodiphenyl ether, 1,5-diaminonaphthalene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, Di-trifluoromethyl-4,4'-diaminobiphenyl, 3,3'-ditrifluoromethyl-4,4'-diaminobiphenyl, 5-amino-1- (4 (4'-aminophenyl) -1,3,3-trimethylindane, 3,4'-diaminodiphenyl ether, 3'- , 3'-diaminobenzophenone, 3,4'-diaminobenzophenone, 4,4'-diaminobenzophenone, 2,2-bis [4- (4-aminophenoxy) 2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2- Bis (4-aminophenoxy) phenyl] sulfone, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 9,9- (4-aminophenyl) fluorene, 4,4'-methylene-bis (2-chloroaniline), 2,2 ' Tetrachloro-4,4'-diaminobiphenyl, 2,2'-dichloro-4,4'-diamino-5,5'-dimethoxybiphenyl, 3,3'-dimethoxy- , 4'-diaminobiphenyl, 1,4,4 '- (p-phenyleneisopropylidene) bisaniline, 4,4' - (m-phenyleneisopropylidene) bisaniline, 2,2'- Bis (trifluoromethyl) biphenyl, 4,4'-diamino-2,2'-bis (trifluoromethyl) biphenyl, Aromatic diazonium salts such as 4'-bis [(4-amino-2-trifluoromethyl) phenoxy] -octafluorobiphenyl and the like Min;

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, a compound represented by formula DI below, a compound represented by formula D- 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 is a monovalent organic group having a ring structure including a nitrogen atom selected from the group consisting of pyridine, pyrimidine, triazine, piperidine and piperazine, X ¹ is a divalent organic group , R ⁶ is an alkyl group having 1 to 4 carbon atoms, and a 1 is an integer of 0 to 3)

[Formula D-II]

(In the formula (D-II), R ⁷ is a divalent organic group, and X ² is a group having a ring structure containing a nitrogen atom selected from the group consisting of pyridine, pyrimidine, triazine, piperidine and piperazine, A plurality of X ^{2 s} present may be the same or different, R ⁸ is each an alkyl group having 1 to 4 carbon atoms, and a 2 is an integer of 0 to 3,

A mono-substituted phenylenediamine such as a compound represented by the following formula (D-III);

[Formula D-III]

(Wherein R ⁹ is a divalent organic group selected from the group consisting of -O-, -COO-, -OCO-, -NHCO-, -CONH- and -CO-, R ¹⁰ is a steroid skeleton , A trifluoromethylphenyl group, a trifluoromethoxyphenyl group, and a fluorophenyl group, or an alkyl group having 6 to 30 carbon atoms, R ¹¹ is an alkyl group having 1 to 4 carbon atoms, and a3 is an integer of 0 to 3)

A diaminoorganosiloxane such as a compound represented by the following formula (D-IV);

[Formula D-IV]

(In the formula (D-IV), R ¹² represents a hydrocarbon group of 1 to 12 carbon atoms, plural R ¹² s may be the same or different from each other, s is an integer of 1 to 3, t is an integer of 1 to 20 Lt; / RTI >

And compounds represented by the following formulas (D-1) to (D-5), respectively. 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 benzene ring of the aromatic diamine may be substituted with one or more alkyl groups having 1 to 4 carbon atoms (preferably a methyl group). It is preferable that R ⁶ , R ⁸ and R ¹¹ in the above formulas DI, D-II and D-III are each a methyl group, and a1, a2 and a3 are each preferably 0 or 1, .

Examples of other diamines that can be used in the present invention include p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfide, 1,5-diaminonaphthalene , 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl, 2,7-diaminofluorene, Bis (4-aminophenoxy) phenyl] propane, 9,9-bis (4-aminophenyl) fluorene, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 4,4 '- (p- phenylenediisopropylidene) bis (4-aminophenoxy) benzene, 4,4'-bis (4-aminophenoxy) biphenyl, 1,4-cyclohexane Diamine, 4,4'-methylenebis (cyclohexylamine), 1,3-bis (aminomethyl) cyclohexane, the compound represented by each of the above formulas D-1 to D- Water, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminoacrylidine, 3,6-diaminocarbazole, , 6-diaminocarbazole, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, N, N'- Among the compounds represented by the formula DI, the compound represented by the following formula D-6, the compound represented by the formula D-7 in the compound represented by the formula D-II, the dodecanoxy -2,4-diaminobenzene, pentadecanoxy-2,4-diaminobenzene, hexadecaneoxy-2,4-diaminobenzene, octadecanoxy-2,4-diaminobenzene, dodecanoxy- Diaminobenzene, pentadecaneoxy-2,5-diaminobenzene, hexadecaneoxy-2,5-diaminobenzene, octadecanoxy-2,5-diaminobenzene, D-8 to D -16 < / RTI > Of the displayed compound 1,3-bis (3-aminopropyl) at least one member selected from the group consisting of tetramethyldisiloxane (hereinafter referred to as "other specific diamine") it is preferred.

[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 preferably contains the compound represented by the formula (1) in an amount of 0.1 mol% or more, preferably 0.1 to 30 mol% , More preferably 0.1 to 20 mol%. The diamine used in the present invention preferably contains other specific diamines as described above in addition to the compound represented by the formula (1). In this case, the proportion of other specific diamines is preferably 30 mol% or more, more preferably 50 mol% or more, and particularly preferably 80 mol% or more based on the total diamine.

[Synthesis of polyamic acid]

The polyamic acid contained in the liquid crystal aligning agent of the present invention is obtained by reacting a tetracarboxylic acid dianhydride with a diamine containing the compound represented by the formula (1).

The ratio of the tetracarboxylic dianhydride and the diamine used in the synthesis reaction of the polyamic acid is preferably such that the amount of the acid anhydride group of the tetracarboxylic dianhydride is from 0.2 to 2 equivalents based on 1 equivalent of the amino group of the diamine, Is from 0.3 to 1.2 equivalents.

The synthesis reaction of the polyamic acid is preferably carried out in an organic solvent, preferably at a temperature of -20 ° C to 150 ° C, more preferably 0 to 100 ° C, for 0.1 to 24 hours, more preferably 0.1 to 12 hours Time. The organic solvent is not particularly limited as long as it can dissolve the polyamic acid to be produced. Examples of the organic solvent include N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, Aprotic polar solvents such as sulfoxide,? -Butyrolactone, tetramethyl urea, and hexamethylphosphoric triamide; phenol solvents such as m-cresol, xylenol, phenol, and halogenated phenol. The amount (a) of the organic solvent used is preferably such that the total amount (b) of the tetracarboxylic acid dianhydride and the diamine compound is 0.1 to 30% by weight based on the total amount (a + b) of the reaction solution. When the organic solvent is used in combination with a poor solvent to be described later, the amount (a) of the organic solvent should be understood to mean the total amount of the organic solvent and the poor 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, di Ethyl 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, 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 an organic solvent and a poor solvent are used in combination, the amount of the poor solvent to be used can be appropriately set within a range in which the polyamic acid to be produced does not precipitate, but is preferably 50% by weight or less, more preferably 40% , And more preferably 30 wt% or less.

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 poor solvent to obtain a precipitate and drying the precipitate under reduced pressure, or by 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.

<Polyimide>

The polyimide which may be contained in the liquid crystal aligning agent of the present invention can be obtained by imidizing the above-mentioned polyamic acid by dehydration ring closure.

Examples of the tetracarboxylic acid dianhydride used in the synthesis of the polyimide include the same compounds as the tetracarboxylic dianhydride used in the synthesis of the polyamic acid described above. The kind of the preferable tetracarboxylic dianhydride and its preferable use ratio are the same as in the case of the polyamic acid.

Examples of the diamine used for synthesizing the polyimide contained in the liquid crystal aligning agent of the present invention include the same diamine as the diamine compound used for the synthesis of the above-mentioned polyamic acid. That is, the diamine used for the synthesis of the polyimide contained in the liquid crystal aligning agent of the present invention includes the compound represented by the above formula (1), and only the compound represented by the above formula (1) And the other diamine may be used in combination. Preferred types of other diamines and the preferable ratio of use of each diamine are the same as those of the polyamic acid.

The polyimide contained in the liquid crystal aligning agent of the present invention may be a completely imidized product in which all of the amic acid structure possessed by the raw material polyamic acid is subjected to dehydration ring closure and dehydration ring closure of only a part of the amic acid structure, It may be a partially imide cargo having an imidazole ring structure.

The imide ratio of the polyimide contained in the liquid crystal aligning agent of the present invention is preferably 30% or more, more preferably 80% or more, and particularly preferably 85% or more.

The imidization ratio is expressed as a percentage of the ratio of the number of imide ring structures to the total number of amide structure and imide ring structure of polyimide. At this time, a part of the imide ring may be an isoimide ring. The imidization rate can be calculated from the results of ¹ H-NMR measurement of tetramethylsilane as a reference material at room temperature by dissolving the polyimide in a suitable deuterated solvent (for example, deuterated dimethyl sulfoxide) 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 precursor of polyimide (polyamic acid) The ratio of the number of other protons to one of the proton of the NH group in the &lt; RTI ID = 0.0 &gt;

The dehydration ring-closure of the polyamic acid is preferably carried out by heating the polyamic acid (i), or (ii) dissolving the polyamic acid in an organic solvent, adding a dehydrating agent and a dehydrating ring-closing catalyst to the solution, . &Lt; / RTI &gt;

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 캜, the dehydration ring-closure reaction does not proceed sufficiently, and if the reaction temperature exceeds 200 캜, the molecular weight of the obtained polyimide may be lowered. The reaction time is preferably 1.0 to 24 hours, more preferably 1.0 to 12 hours.

On the other hand, in the method of adding the dehydrating agent and dehydrating ring-closing catalyst to the solution of the polyamic acid of the above (ii), for example, an acid anhydride such as acetic anhydride, propionic anhydride or trifluoroacetic anhydride can be used. The amount of the dehydrating agent to be used is preferably from 0.01 to 20 mol based on 1 mol of the amic acid structure of the polyamic acid although it differs depending on the desired imidization ratio. 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. The imidization rate can be increased as the amount of the dehydrating agent and the dehydrating ring closure agent used is larger. 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 of the dehydration ring closure reaction is preferably 0 to 180 ° C, more preferably 10 to 150 ° C. The reaction time is preferably 1.0 to 24 hours, more preferably 1.0 to 12 hours.

The polyimide obtained in the above method (i) can be used as it is for the production of a liquid crystal aligning agent, or after the obtained polyimide is purified, it can be used for the production of a liquid crystal aligning agent. On the other hand, in the method (ii), a reaction solution containing polyimide is obtained. This reaction solution can be used as it is for the preparation of a liquid crystal aligning agent, after removing the dehydrating agent and the dehydration ring-closing catalyst from the reaction solution, it can be used for the preparation of a liquid crystal aligning agent or after the polyimide is isolated, 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 polyimide can be carried out by performing the same operation as described above as a method for isolating and purifying polyamic acid.

- Polymers of terminal modified type -

The polyamic acid or polyimide contained in the liquid crystal aligning agent of the present invention may be a terminal modified type having a controlled molecular weight. By using the polymer of the terminal modified type, the coating property and the like of the liquid crystal aligning agent can be further improved without impairing the effect of the present invention. Such a terminal modified polymer can be produced by adding a molecular weight regulator to a polymerization reaction system when synthesizing a polyamic acid. Examples of the molecular weight regulator include acid monoanhydrides, monoamine compounds, and monoisocyanate compounds.

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. have. Examples of the monoamine compound include aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, hexadecylamine, n-heptadecylamine, n-octadecylamine, n-octadecylamine, n-octadecylamine, Eicosylamine and the like. Examples of the monoisocyanate compound include phenyl isocyanate and naphthyl isocyanate.

The use ratio of the molecular weight modifier is preferably 30 parts by weight or less, more preferably 20 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.s) of the polymer is preferably 10% by weight of a polymer solution prepared by using a good solvent for the polymer (for example,? -Butyrolactone, N-methyl-2-pyrrolidone or the like) Measured at 25 캜 using an E-type rotational viscometer.

<Other additives>

The liquid crystal alignment film of the present invention contains at least one selected from the group consisting of polyamic acid as described above and polyimide obtained by imidizing it as an essential component, but may contain other components as necessary. Such other components include, for example, other polymers, compounds having at least one epoxy group in the molecule (hereinafter referred to as "epoxy compound"), and functional silane compounds.

These other polymers can be used for improving solution properties and electrical properties. Such another polymer is a polymer other than polyimide obtained by reacting a tetracarboxylic dianhydride with a diamine containing a compound represented by the above formula (1) and dehydration cyclization of the polyamic acid, for example, tetracarboxylic acid (Hereinafter referred to as "other polyamic acid") obtained by reacting a bisamic acid dianhydride with a diamine not containing the compound represented by the formula (1), polyimide obtained by dehydration ring closure of the polyamic acid Poly (styrene-phenylmaleimide) derivatives, poly (meth) acrylate, and the like can be given as examples of the polyimide resin, polyimide resin, polyimide resin, polyimide resin, polyimide resin, polyimide resin, . Of these, other polyamic acids or other polyimides are preferable, and other polyamic acids are more preferable.

The proportion of the other polymer used may be selected from the sum of the polymers (polyamic acid obtained by reacting the tetracarboxylic dianhydride with a diamine containing the compound represented by the formula (1), polyimide obtained by dehydration ring closure of the polyamic acid, More preferably 0.1 to 40% by weight, and more preferably 0.1 to 30% by weight, based on the total amount of the polymer and the polymer.

Examples of the epoxy 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, N, N-diglycidyl- -Aminomethylcyclohexane and the like can be preferably used. The compounding ratio of these epoxy group-containing compounds is preferably 40 parts by weight or less, more preferably 0.1 to 30 parts by weight, based on 100 parts by weight of the total amount of the polymers.

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-ureidopropyltriethoxy Silane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyl triethylenetriamine, N- 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 compounding ratio of these functional silane-containing compounds is preferably 40 parts by weight or less based on 100 parts by weight of the total of the polymers.

The liquid crystal aligning agent of the present invention is constituted by dissolving and containing at least one polymer selected from the group consisting of polyamic acid and polyimide as described above and optionally other additives optionally mixed 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 components other than the solvent of the liquid crystal aligning agent to the total weight of the liquid crystal aligning agent) is appropriately selected in consideration of viscosity, volatility, etc., To 10% 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% by weight and the solution viscosity is in the range of 12 to 50 mPa · s. In the case of the ink-jet method, it is particularly preferable that the solid 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 캜, more preferably 20 to 60 캜.

<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). The step (1) differs depending on the desired operation mode, the preferred application method of the substrate, the liquid crystal aligning agent, and the heating temperature after application of the liquid crystal aligning agent. Steps (2) and (3) are common to each operation mode.

(1) First, the liquid crystal aligning agent of the present invention is applied onto a substrate, and then a coated film is formed on the substrate by heating the coated surface.

(1-1) In the case of manufacturing a TN type, STN type or VA type liquid crystal display device, two substrates on which a patterned transparent conductive film is provided are paired, and on the respective transparent conductive film- The alignment agent is preferably applied by the offset printing method, the spin coating method or the inkjet printing method, respectively, and then the coated surfaces are heated to form a coating film. Examples of the substrate include glass such as float glass and soda glass; A transparent substrate including plastic such as polyethylene terephthalate, polybutylene terephthalate, polyether sulfone, polycarbonate, and poly (alicyclic olefin) can be used. As the transparent conductive film to be provided on one side of the substrate, an ITO film including indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ), a NESA film containing tin oxide (SnO ₂ ) In order to obtain a patterned transparent conductive film, for example, a method of forming a pattern by photoetching after forming a transparent conductive film without a pattern, a method of using a mask having a desired pattern in forming a transparent conductive film And the like. When applying the liquid crystal aligning agent, a functional silane compound, a functional titanium compound and the like are previously coated on the surface of the substrate surface on which the coating film is to be formed, in order to further improve adhesion between the substrate surface and the transparent conductive film and the coating film A pretreatment may be performed.

The heating temperature after application of the liquid crystal aligning agent is preferably 30 to 300 캜, more preferably 40 to 250 캜, and the heating time is preferably 1 to 60 minutes, more preferably 10 to 30 minutes. 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.

(1-2) On the other hand, in the case of manufacturing an IPS type liquid crystal display element, the conductive film formation surface of the substrate on which the transparent conductive film patterned in the comb-like pattern is provided and the conductive film formation surface of the opposite substrate on which the conductive film is not provided The liquid crystal aligning agent of the present invention is preferably applied by a roll coater method, a spinner method, or an inkjet printing method, respectively, and then each coated surface is heated to form a coated film.

The material of the substrate and the transparent conductive film used in this case, the method of patterning the transparent conductive film, and the pretreatment of the substrate are the same as those in (1-1) above.

The heating temperature after application of the liquid crystal aligning agent is preferably 80 to 300 ° C, more preferably 120 to 250 ° C, and the heating time is preferably 1 to 60 minutes, more preferably 10 to 30 minutes.

The preferable film thickness of the formed coating film is the same as that of the above (1-1).

In any of the cases of (1-1) and (1-2), 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, but the liquid crystal aligning agent of the present invention may be a polyamic acid or imide ring When the imidized polymer containing the structure and the amic acid structure is contained, the dehydrated ring-closure reaction may be further advanced by heating after forming the coating film, so that a more imaged coating film can be obtained.

(2) When the liquid crystal display element manufactured by the method of the present invention is a VA type liquid crystal display element, the coating film formed as described above can be used as it is as a liquid crystal alignment film, It can also be used afterwards.

On the other hand, when a liquid crystal display device other than the VA type is manufactured, a coating film formed as described above is subjected to rubbing treatment to form a liquid crystal alignment film.

The rubbing treatment can be carried out by a method of rubbing the coating film surface formed as described above in a predetermined direction with a roll of cloth, for example, 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 film formed as described above is also disclosed in, for example, Patent Document 5 (Japanese Patent Application Laid-Open No. 6-222366) and Patent Document 6 (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 liquid crystal alignment film as described in the present invention with ultraviolet rays and a process of changing the pretilt angle of a part of the liquid crystal alignment film as described in Patent Document 7 (Japanese Patent Application Laid-open No. 5-107544 A process of forming a resist film on a part of the surface of the same liquid crystal alignment film and then rubbing treatment in a direction different from the rubbing treatment performed previously is performed to remove the resist film so that the liquid crystal alignment film has a liquid crystal aligning ability different for each region, It is possible to improve the clock characteristic of the clock.

(3) A liquid crystal cell is prepared by preparing two substrates on which a liquid crystal alignment film is formed as described above, and arranging the liquid crystal between two substrates arranged opposite to each other. Here, when the coating film is subjected to the rubbing treatment, the two substrates are opposed to each other such that the rubbing directions in the coating films are mutually orthogonal or opposite to each other at a predetermined angle.

In order to produce a liquid crystal cell, for example, the following two methods can be mentioned.

The first method is a conventionally known method. First, two substrates are opposed to each other with a gap (cell gap) so that the respective liquid crystal alignment films face each other, and two peripheral portions of the substrates are bonded together using a sealant. The cell spacing The liquid crystal cell can be manufactured by sealing the injection hole after filling and filling the liquid crystal in the liquid crystal cell.

The second method is a method called ODF (One Drop Fill) method. An ultraviolet light curable sealing material is applied to a predetermined place on one of the two substrates on which the liquid crystal alignment film is formed and the liquid crystal is dropped on the liquid crystal alignment film surface and then the other substrate is bonded so that the liquid crystal alignment film is opposed And then the ultraviolet light is irradiated to the entire surface of the substrate to cure the sealing agent, whereby the liquid crystal cell can be manufactured.

In any method, it is preferable to heat the liquid crystal cell manufactured as described above to a temperature at which the liquid crystal used is isotropic, and gradually cool to room temperature to remove the flow alignment at the time of liquid crystal injection.

Further, by bonding a polarizing plate to the outer surface of the liquid crystal cell, the liquid crystal display element of the present invention can be obtained.

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

As the liquid crystal, for example, a nematic liquid crystal, a smectic liquid crystal or the like can be used, and among them, a nematic liquid crystal is preferable. In the VA type liquid crystal cell, a nematic liquid crystal having a negative dielectric anisotropy is preferable, and examples thereof include a dicyanobenzene liquid crystal, a pyridazine liquid crystal, a Schiff salt mechanical liquid crystal, an agar liquid crystal, a biphenyl liquid crystal, Hexane-based liquid crystal or the like is used. In the case of a TN type liquid crystal cell or an STN type liquid crystal cell, a nematic liquid crystal having positive dielectric anisotropy is preferable. For example, biphenyl type liquid crystal, phenyl cyclohexane type liquid crystal, ester type liquid crystal, terphenyl type liquid crystal, Phenylcyclohexane-based liquid crystal, pyrimidine-based liquid crystal, dioxane-based liquid crystal, bicyclooctane-based liquid crystal, quartz-based liquid crystal and the like. Examples of the liquid crystal include cholesteric liquid crystals such as cholestyl chloride, cholesteryl nonanoate, and cholesteryl carbonate; Chiral agents such as those sold under the trade names C-15 and CB-15 (Merck); and a ferroelectric liquid crystal such as p-disiloxybenzylidene-p-amino-2-methylbutyl cinnamate may be further added.

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. Hereinafter, the solution viscosities of the polymers are all values measured at 25 DEG C using an E-type viscometer.

<Synthesis Example of Compound Represented by Formula 1>

Synthesis Example 1

N, N-dioctyl-1,2,4-phenylenetriamine was synthesized according to Reaction Scheme 1 below.

11.0 g (0.06 mol) of 2,4-dinitrofluorobenzene, 10.0 g (0.066 mol) of cesium fluoride and 14.5 g (0.6 mol) of di-n-octylamine were mixed in a 300 mL three- To this was added 60 mL of dimethylsulfoxide to obtain a stirred solution. This solution was heated and stirred under nitrogen at 110 DEG C for 6 hours to carry out the reaction. After completion of the reaction, 200 mL of chloroform was added to the reaction mixture, and the mixture was extracted and washed with 100 mL of ion-exchanged water four times. The organic layer was dehydrated with magnesium sulfate and then removed by filtration. The filtrate was concentrated and the solvent was removed to obtain 23.7 g of dinitro intermediate.

Subsequently, 12.2 g (0.03 mol) of the dinitro intermediate synthesized above and 10.9 g of palladium carbon (Pd / C) were added to a 300 mL three-necked flask under a nitrogen atmosphere, and further 180 mL of ethanol was added thereto. Lt; / RTI &gt; Thereafter, 18.4 mL of hydrazine monohydrate was added dropwise, and the mixture was reacted by stirring at 80 캜 for 3 hours under nitrogen. After completion of the reaction, the catalyst was removed by filtration, and the filtrate was concentrated to remove the solvent. The obtained viscous liquid was purified by a column chromatography (chloroform / acetone = 10/1 (volume ratio)), concentrated and the solvent was removed to obtain 7.1 g of N, N-dioctyl-1,2,4-phenylenetriamine .

A ¹ H-NMR chart of this compound is shown in Fig.

<Synthesis Example of Other Polyamic Acid>

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, 4,4'-di 198 g (1.0 mole) of minodiphenylmethane was dissolved in a mixed solvent containing 230 g of N-methyl-2-pyrrolidone and 2,060 g of? -Butyrolactone, and the mixture was reacted at 40 占 폚 for 3 hours, 1,350 g of butyrolactone was added to obtain about 4,000 g of a solution containing 10 wt% of polyamic acid (A-1). 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 a tetracarboxylic dianhydride and 212 g of 2,2'-dimethyl-4,4'-diaminobiphenyl as a diamine (A-2) was obtained by dissolving polyamic acid (1.0 mol) in a mixed solvent containing 370 g of N-methyl-2-pyrrolidone and 3,300 g of? -Butyrolactone and conducting a reaction at 40 占 폚 for 3 hours. &Lt; / RTI &gt; was obtained. The solution viscosity of this solution was 160 mPa..

<Synthesis of polyimide>

Synthesis Example 4

11.2 g (0.050 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as a tetracarboxylic dianhydride and 13.2 g (0.050 mol) of 1,3,3a, 4,5,9b-hexahydro- 15.7 g (0.050 mol) of p-phenylene diamine as diamine, 9.0 g (0.084 mol) of p-phenylenediamine as diamine, , 2.5 g (0.010 mol) of 1,3-bis (3-aminopropyl) -tetramethyldisiloxane and 1.7 g of N, N-dioctyl-1,2,4-phenyllinthiamine obtained in Synthesis Example 1 0.0050 mol) and 0.28 g (0.0030 mol) of aniline as a monoamine were dissolved in 96 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, 270 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, and 40 g of pyridine and 41 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 a solvent with a new? -Butyrolactone (pyridine and acetic anhydride used in the dehydration ring closure reaction were removed from the system by this operation) to obtain a polyimide having an imidization rate of about 95% -1) in an amount of 15% by weight. A small amount of the obtained polyimide solution was fractionated, and the solution viscosity measured as a solution having a polyimide concentration of 6.0 wt% by adding? -Butyrolactone was 16 mPa 占 퐏.

&Lt; Production and evaluation of liquid crystal aligning agent >

Example 1

(I) Production of liquid crystal aligning agent

A solution containing the polyamic acid (A-1) obtained in Synthesis Example 2 and the solution containing the polyimide (B-1) obtained in Synthesis Example 4 was mixed with the polyamic acid (A-1) ) Was added in an amount of 80:20 (weight ratio), and γ-butyrolactone (BL), N-methyl-2-pyrrolidone (NMP) and butyl cellosolve (BC) 10 parts by weight of N, N, N ', N'-tetraglycidyl-4,4'-diaminodiphenyl methane as an epoxy compound was added to 100 parts by weight of the total of 100 parts by weight of the polymer and sufficiently stirred to obtain a solvent composition BL : NMP: BC = 71: 17: 12 (weight ratio), and a solid content concentration of 6.0 wt%. This solution was filtered using a filter having a pore size of 1 占 퐉 to prepare a liquid crystal aligning agent.

(II) Evaluation of liquid crystal aligning agent

(1) Evaluation of printability

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 by using a liquid crystal alignment film printing machine (manufactured by Nippon Sha Sein Insights Co., Ltd.) After the solvent was removed by preliminary baking (prebaking), the film was heated (post baked) on a hot plate at 200 DEG C for 10 minutes to form a coating film having an average film thickness of 600 ANGSTROM. The coating film was observed with a microscope having a magnification of 20 times to examine whether the printing was uneven or pinholes. As a result, unevenness in printing and pinholes were not observed, and printing properties were good.

(2) Evaluation of Film Thickness Uniformity of Coating Film

With respect to the coating film formed above, the film thickness at the central portion of the substrate and the film thickness at a position near the center of 15 mm from the outer end 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 Sein Insights Co., Ltd.) and heated on a hot plate at 80 캜 for 1 minute (Prebaked) to remove the solvent, and then heated (post baked) on a hot plate at 200 DEG C for 10 minutes to form a coating film having an average thickness of 600 ANGSTROM.

The coating film was subjected to a rubbing treatment with a rubbing machine having a roll on which a rayon spring was wound 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 heat resistance stability

A rectangular wave of 30 Hz and 3.0 V, in which an alternating current of 6.0 V (peak-to-peak) was superimposed, 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 heat stability was evaluated as "good" when no display defect was observed, and when the display defect was observed, the heat stability was judged as " Respectively.

Example 2

A liquid crystal aligning agent was obtained in the same manner as in Example 1, except that the solution containing the polyamic acid (A-2) obtained in Synthesis Example 3 was used instead of the solution containing the polyamic acid (A-1) And as a result, unevenness in printing and pinholes were not observed in the coating film, printability was good, film thickness uniformity of the coating film, and heat stability of the resulting liquid crystal cell were both good.

1 is a ¹ H-NMR chart of N, N-dioctyl-1,2,4-phenylenetriamine obtained in Synthesis Example 1. FIG.

Claims (6)

A first polymer selected from the group consisting of a polyamic acid obtained by reacting a tetracarboxylic acid with a diamine including a compound represented by the following formula (1) and a polyimide obtained by dehydrocondylating the polyamic acid, and A polyamic acid obtained by reacting a tetracarboxylic acid with a diamine not containing a compound represented by the following formula 1 or a polyimide obtained by dehydration ring closure of the polyamic acid, Wherein the liquid crystal aligning agent is a liquid crystal aligning agent. &Lt; Formula 1 >

(Wherein R &lt; 1 & gt ^; and R &lt; ^II & gt ^; are each independently an alkyl group having 1 to 30 carbon atoms) The liquid crystal aligning agent according to claim 1, wherein the first polymer is polyimide and the imidization rate thereof is 30% or more. The liquid crystal aligning agent according to claim 1, wherein the second polymer is a polyamic acid. The liquid crystal aligning agent according to claim 1, further comprising a compound having at least one epoxy group in the molecule. A liquid crystal display element comprising a liquid crystal alignment film formed of the liquid crystal alignment agent according to any one of claims 1 to 4. delete

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