TW201736440A - Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element - Google Patents

Abstract

Provided is a liquid crystal alignment agent for obtaining a liquid crystal alignment film capable of reducing liquid crystal non-uniformities generated in an ODF scheme and the like. A liquid crystal alignment agent characterized in containing at least one type of polymer selected from the group consisting of: a polyamic acid obtained by reacting a tetracarboxylic acid dianhydride component and a diamine component containing a diamine having a crown ether structure and an aromatic ring, and a diamine having a side chain for expressing a liquid crystal pretilt angle; and a polyimide obtained by imidizing the polyamic acid.

Description

Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element

The present invention relates to a liquid crystal alignment agent, a liquid crystal alignment film, and a liquid crystal display element using the same, which are used in the production of a liquid crystal alignment film.

In the liquid crystal display device, for example, there is a long axis of nematic liquid crystal having positive dielectric anisotropy between two electrode substrates in which a liquid crystal alignment film is formed on an electrode, and one of the substrates is continuous to the other substrate. On a 90° torsion twisted nematic (TN: Twisted Nematic) type liquid crystal display element or a single-sided substrate, an electric field is generated in the lateral direction with respect to the substrate surface by forming an electrode in a meandering shape, and a transverse electric field of the liquid crystal is driven. Effect (IPS: In-Plane Switching) type liquid crystal display element. In addition, a vertical (VA: Vertical Allignment) liquid crystal display device having a negative dielectric anisotropy nematic liquid crystal and a vertical alignment with respect to the substrate surface has been developed. In the liquid crystal alignment film used for the liquid crystal display device, a polyimine-based liquid crystal alignment film is mainly used, and a polyimide-based alignment film of various structures has been developed (for example, see Patent Document 1).

When liquid crystal display elements are fabricated, liquid crystals need to be formed The step of filling the liquid crystal between the two substrates (the liquid crystal gap: cell gap) of the alignment film. Conventionally, in the case of liquid crystal filling, a vacuum injection method in which liquid crystal is filled between two substrates is used by a pressure difference between atmospheric pressure and vacuum. However, in this case, since the liquid crystal injection port is provided only on one side of the substrate, the liquid crystal is filled between the substrates having a gap of 3 to 5 μm in the liquid crystal layer, and it takes a long time. Therefore, the manufacturing steps of the liquid crystal display element are simplified. Especially in the manufacture of liquid crystal TVs or large monitors, it becomes a big problem.

Therefore, in order to solve the problem of the vacuum injection method described above, a liquid crystal dropping method (ODF method) has been developed. In this method, the liquid crystal is dropped onto the substrate on which the liquid crystal alignment film is formed, and after bonding to the other substrate in a vacuum, the sealing material is UV-cured to fill the liquid crystal.

In addition, as the high definition of the liquid crystal display element is deepened, it is necessary to suppress display unevenness. The liquid crystal dropping method is solved by reducing the amount of liquid crystal dripping, increasing the degree of vacuum during lamination, and the like, and optimizing the manufacturing steps of adsorbing water or impurities. However, as the liquid crystal display device manufacturing line has become larger, the manufacturing steps up to now have been optimized, and it has become impossible to suppress display unevenness, and it is necessary to reduce the misalignment of the liquid crystal alignment film more than ever.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 11-249148

[Summary of the Invention]

In the ODF method, since the liquid crystal is directly dropped onto the alignment film, when the liquid crystal is dropped, physical stress is applied to the alignment film or liquid crystal must be filled in the entire area of the panel, and the dropping point of the liquid crystal must be increased. Therefore, in the lower portion of the liquid crystal droplet or the portion in contact with the liquid droplet adjacent to the droplet of the liquid crystal, so-called alignment unevenness such as dropping marks or lattice unevenness may occur, and in the case of the liquid crystal display element, there may be a misalignment. The problem of uneven display caused by both. This alignment unevenness is considered to be due to adsorption of water or impurities attached to the surface of the liquid crystal alignment film formed on the substrate, in the ODF step, the liquid crystal which is dropped is swept, and the portion below the liquid crystal droplet or the droplet of the liquid crystal contacts each other. Due to the difference in adsorbed water or impurities.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a liquid crystal alignment agent which can form a liquid crystal alignment film which can reduce uneven liquid crystal alignment which occurs in an ODF method, and to provide a reduction in ODF-based manner. A liquid crystal display element in which display unevenness is caused by uneven liquid crystal alignment.

As a result of intensive studies by the inventors, the present invention for achieving the above problems has been completed.

That is, the present invention is intended to have the following technical requirements.

A liquid crystal alignment agent comprising a polymer which is a polymer a polyamic acid selected from the group consisting of a diamine component containing a diamine having a crown ether structure and an aromatic ring and a diamine having a side chain exhibiting a pretilt angle of a liquid crystal, and a tetracarboxylic dianhydride component, and the poly At least one of a group of polyamidimides of hydrazine imide.

2. A liquid crystal alignment film obtained from the liquid crystal alignment agent described above.

A liquid crystal display device comprising the liquid crystal alignment film described above.

According to the liquid crystal alignment agent of the present invention, it is possible to obtain a liquid crystal alignment film which can reduce liquid crystal alignment unevenness which occurs in a liquid crystal display element in which a liquid crystal cell is filled in a liquid crystal cell by liquid crystal dropping (ODF). Further, a liquid crystal display element which can reduce display unevenness caused by uneven alignment of liquid crystals generated by the ODF method or the like can be obtained.

According to the liquid crystal alignment agent of the present invention, it is possible to reduce the unevenness of the liquid crystal alignment which occurs in the ODF method, etc., although it is not clear, the crown ether used in the raw material of the liquid crystal alignment agent of the present invention has a macrocyclic ether structure. Therefore, when the structure having a carboxyl group or a basic heterocyclic ring structure is used (refer to International Publication No. WO2011-010619, WO2012-014898), the hydrophobicity is high and it is hard to be affected by the adsorption of water or impurities. It becomes less prone to uneven liquid crystal alignment.

[Formation of the Invention] <Diamine containing a crown ether structure and an aromatic ring>

The diamine having a crown ether structure and an aromatic ring (hereinafter also referred to as a specific diamine 1) is not limited as long as it has a crown ether structure and an aromatic ring structure. However, when the ring having a large volume structure or a large molecular weight is excessively excessive, the liquid crystal alignment property may be disturbed. Therefore, it is preferably a molecular weight of 250 to 1,500, particularly preferably 250 to 1,000.

Here, the aromatic ring may be either a homocyclic ring or a heterocyclic ring, and in the case of a homocyclic ring, the residue after removing one hydrogen atom of the homocyclic aromatic compound, and in the case of a heterocyclic ring, for example, In the case of a heterocyclic aromatic compound containing a nitrogen atom, it is a residue which has one hydrogen atom of a heterocyclic aromatic compound containing a nitrogen atom.

Specific examples of the above-mentioned homocyclic aromatic compound include cyclopentadiene, benzene, anthracene, naphthalene, anthracene, phenanthrene, anthracene, fused tetraphenyl, benzopyrene, hydrazine, pentacene, and phenalkenylene. (Phenalene), hydrazine, hydrazine, biphenylene, and the like.

Further, specific examples of the heterocyclic aromatic compound containing a nitrogen atom of the above heterocyclic ring include pyrrole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, tetrazine, imidazole, pyrazole, oxazole, and isoxazole. (isoxazole), oxadiazole, thiazole, isothiazole, thiadiazole triazole, tetrazole, guanidine, oxazole, benzimidazole, benzoxazole, benzisoxazole, benzothiazole, benzopyrene Thiazole, quinoline, isoquinoline, Chinorin, pyridazine, quinazoline, quinoxaline, naphthalene, pteridine, anthracene, coumarin, isocoumarin, carbazole, acridine, phenanthroline, thiophene Pyridine, furopyridine (furopyridine), pyridazine, quinolizine, porphyrin and the like. Further, the N-H moiety in pyrrole, pyrazole, imidazole or the like may be alkylated directly or by methylation or the like.

The hydrogen atom on the carbon atom or the nitrogen atom of the ring in the heterocyclic aromatic compound or the heterocyclic aromatic compound containing a nitrogen atom may be substituted. The type or number of the substituent is not particularly limited, but an electron-donating substituent having a relatively small molecular weight such as a methyl group, an ethyl group, an alkoxy group, a methoxy group, an ethoxy group, an amine group or a dimethylamino group is preferable. It is preferred that the electron-donating substituent having a relatively small molecular weight such as a carboxyl group, a nitro group or a cyano group is activated by electrons. The position of the substituent in the homocyclic aromatic compound or the heterocyclic aromatic compound is not particularly limited, but in the case of the nitrogen-containing heterocyclic aromatic compound, the position of the substituent is preferably not adjacent to the nitrogen atom.

In addition, from the viewpoints of liquid crystal alignment properties, friction resistance, ease of synthesis, and the like in the case of a liquid crystal alignment film, it is preferred to be an unsubstituted or homocyclic ring aromatic substituted with a relatively small substituent such as a methyl group or an ethyl group. a compound or a heterocyclic aromatic compound containing a nitrogen atom.

In the present invention, a preferred example of the specific diamine 1 is a diamine represented by the following formula (1).

In the formula (1), X ¹ and X ² each independently represent a single bond or -(OCH ₂ CH ₂ ) _n -. Here, n represents an integer of 1 to 6, preferably an integer of 1 to 4. R ¹ represents any of the following two structures. Also, two R ^{1 's} may be the same or different).

In the above formula wherein R ¹ , R ² and R ⁴ each independently represent a single bond or an alkylene group having 1 to 5 carbon atoms, R ³ represents a single bond, an alkylene group having 1 to 5 carbon atoms or a carbonyl group, and X represents an aromatic group. ring.

The aromatic ring is preferably benzene, pyridine, pyridazine, pyrimidine, pyrazine, triazine pyrrole, oxazole, oxadiazole, thiazole, thiadiazole, imidazole, pyrazole, or triazole. Among them, benzene is preferred.

Preferred examples of the specific diamine 1 include the following DA-1 to DA-10. Among them, DA-2, DA-3, DA-6 or DA-7 is preferred.

The specific diamine 1 is preferably used in an amount of 10 to 80 mol%, more preferably 10 to 70 mol%, particularly preferably 20 to 50 mol%, based on the diamine component (1 mol) used for the synthesis of polylysine.

<Diamine having a side chain exhibiting a pretilt angle of liquid crystal>

a diamine having a side chain exhibiting a pretilt angle of a liquid crystal (hereinafter also referred to as a special The diamine 2) may, for example, be a diamine having a long-chain alkyl group, a perfluoroalkyl group, an aromatic cyclic group, an aliphatic cyclic group or a combination thereof, or a steroid skeleton group. It is represented by the following general formula.

X ₁ is selected from the group consisting of -O-, -CH ₂ O-, -COO-, -(CH ₂ ) _a - (a is an integer from 1 to 10), -NH-, -N(CH ₃ )-, -CONH -, -NHCO-, -OCO-, -CON(CH ₃ )-, -N(CH ₃ )CO-, or a divalent organic group of a single bond. X ₂ is a divalent organic group selected from the group consisting of a single bond or -(CH ₂ ) _b - (b is an integer of 1 to 10). X ₃ is selected from the group consisting of a single bond, -(CH ₂ ) _c - (c is an integer from 1 to 10), -O-, -NH-, -N(CH ₃ )-, -CONH-, -NHCO-, - a divalent organic group of CH ₂ O-, -COO-, -OCO-, -CON(CH ₃ )-, or -N(CH ₃ )CO-. X ₄ is a divalent cyclic group selected from a benzene ring, a cyclohexane ring or a heterocyclic ring, or a divalent organic group having a carbon number of 12 to 25 having a steroid skeleton, and any hydrogen atom on the above cyclic group may be It is selected from the group consisting of an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxy group having 1 to 3 carbon atoms, and a fluorine atom.

X ₅ represents a divalent cyclic group selected from a cyclohexane ring, a benzene ring, or a heterocyclic ring, and any hydrogen atom on the cyclic group may be selected from an alkyl group having 1 to 3 carbon atoms and a carbon number of 1 The alkoxy group of ~3, the fluorine-containing alkyl group having 1 to 3 carbon atoms, or the fluorine-containing alkoxy group having 1 to 3 carbon atoms and a fluorine atom are substituted. n is an integer from 0 to 4.

X ₆ is an alkyl group having 1 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, a fluorine-containing alkoxy group having 1 to 18 carbon atoms, or a hydrogen atom. An integer from 1 to 4.

In X ₁ , a single bond, -(CH ₂ ) _a - (a is an integer of 1 to 10), -O-, -CONH-, -CH ₂ O-, or -COO-, is easy to synthesize a side chain structure, so Preferably. More preferably a single _{bond, - (CH 2) a -} (a is an integer of 1 to 10), - O -, - CONH -, - CH 2 O-, or -COO-. More preferably, it is a single bond, -(CH ₂ ) _a - (a is an integer of 1 to 10), -O-, -CH ₂ O- or -COO-.

In X ₂ , a single bond or -(CH ₂ ) _b - (b is an integer of 1 to 10) is preferred.

In X ₃ , a single bond, -(CH ₂ ) _c - (c is an integer of 1 to 10), -O-, -CH ₂ O-, -COO-, or -OCO- is preferred because it is easily synthesized. More preferably a single _{bond, - (CH 2) c -} (c is an integer of 1 to 10), - O -, - CH 2 O -, - COO-, or -OCO-.

In X ₄ , a benzene ring, a cyclohexane ring, that is, a phenyl group, a cyclohexyl group, or an organic group having a steroid skeleton having 12 to 25 carbon atoms is preferred.

In X ₅ , a benzene ring or a cyclohexane ring is preferred.

X ₆ is preferably an alkyl group having 1 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, or a fluorine-containing alkoxy group having 1 to 10 carbon atoms. More preferably, it is an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. More preferably, it is an alkyl group having 1 to 9 carbon atoms or an alkoxy group having 1 to 9 carbon atoms.

n is preferably an integer from 0 to 2. m is preferably an integer of 1 to 2.

Preferred combinations of X ₁ , X ₂ , X ₃ , X ₄ , X ₅ , X ₆ , and n in the formula [1] include 11 pages to 32 of International Publication WO2011/132752 (2011.10.27 publication). The same combination of (1-1) to (1-629) described in Tables 1 to 42 of the page.

Specific examples of the diamine compound having a side chain exhibiting a pretilt angle of the liquid crystal are listed below, but the present invention is not limited thereto.

In the above formula [1a-1] and formula [1a-2], R ₁ represents -O-, -OCH ₂ -, -CH ₂ O-, -COOCH ₂ -, -CH ₂ OCO-, R ₂ -based carbon number 1 or more and 22 or less alkyl groups, alkoxy groups, fluorine-containing alkyl groups, or fluorine-containing alkoxy groups).

In the above formula [1a-3] to formula [1a-5], R ₃ represents -COO-, -OCO-, -CONH-, -NHCO-, -COOCH ₂ -, -CH ₂ OCO-, -CH ₂ O -, -OCH ₂ -, or -CH ₂ -, R ₄ is an alkyl group having 1 or more and 22 or less carbon atoms, an alkoxy group, a fluorine-containing alkyl group or a fluorine-containing alkoxy group).

In the above formula [1a-6], and in the formula [1a-7], R ₅ represents -COO-, -OCO-, -CONH-, -NHCO-, -COOCH ₂ -, -CH ₂ OCO-, -CH ₂ O -, -OCH ₂ -, -CH ₂ -, -O-, or -NH-, R ₆ is a fluoro group, a cyano group, a trifluoromethyl group, a nitro group, an azo group, a methyl group, an ethyl group, Ethyloxy, or hydroxy).

In the above formula [1a-8] and formula [1a-9], R ₇ is an alkyl group having 3 or more and 12 or less carbon atoms, and a cis-trans isomer of 1,4-cyclohexylene group, each being a cis isomer.

In the above formula [1a-10] and formula [1a-11], R ₈ is an alkyl group having 3 or more and 12 or less carbon atoms, and a cis-trans isomer of 1,4-cyclohexylene group, each being a cis isomer.

In the above formula [1a-12], A ₄ is an alkyl group having 3 to 20 carbon atoms which may be substituted by a fluorine atom, A ₃ is a 1,4-cyclohexyl group, or a 1,4-phenylene group, and A ₂ is An oxygen atom, or -COO-* (but with a "*" linkage and A ₃ linkage), A ₁ is an oxygen atom, or -COO-* (but with a "*" linkage and (CH ₂ )a ₂ ) Bonding). Further, a ₁ is an integer of 0 or 1, a ₂ is an integer of 2 to 10, and a ₃ is an integer of 0 or 1.

The diamine having a side chain exhibiting a pretilt angle of the liquid crystal used in the liquid crystal alignment agent of the present invention is preferably 10 to 80 mol%, more preferably 20 to 80 mol%, more preferably 20 to 80 mol%, based on the diamine component (1 mol). It is 20~70mol%.

<Other diamines>

In the case of obtaining the liquid crystal alignment agent of the present invention, a specific diamine can be used. Other diamines other than 1, 2. Examples of the other diamine include an alicyclic diamine, an aromatic diamine, a heterocyclic diamine, an aliphatic diamine, and an aromatic-aliphatic diamine. Specific examples of the diamine are shown below.

Examples of the alicyclic diamine include 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, 4,4'-diaminodicyclohexylmethane, and 4,4'- Diamino-3,3'-dimethyldicyclohexylamine, isophorone diamine, and the like.

Examples of the aromatic diamines include o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 2,4-diaminotoluene, 2,5-diaminotoluene, and 3,5-di. Aminotoluene, 3,5-diamino-N,N-diallylaniline, 2,4-diamino-N,N-diallylaniline, 1,4-diamino-2- Methoxybenzene, 2,5-diamino-p-xylene, 1,3-diamino-4-chlorobenzene, 3,5-diaminobenzoic acid, 1,4-diamino-2 , 5-dichlorobenzene, 4,4'-diamino-1,2-diphenylethane, 4,4'-diamino-2,2'-dimethylbibenzyl (Bibenzyl), 4 , 4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diamino-3,3 '-Dimethyldiphenylmethane, 2,2'-diaminoguanidine, 4,4'-diaminoguanidine, 4,4'-diaminodiphenyl ether, 3,4'-diamine Diphenyl ether, 4,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl fluorene, 3,3'-diaminodiphenyl fluorene, 4,4'-diamine Benzophenone, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxyl) Benzo, 3,5-bis(4-aminophenoxy)benzoic acid, 4,4'-bis(4-aminophenoxy)bibenzyl, 2, 2-bis[(4-aminophenoxy)methyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis[4- (4-Aminophenoxy)phenyl]propane, bis[4-(3-aminophenoxy)phenyl]anthracene, bis[4-(4-aminophenoxy)phenyl]anthracene, 1,3-bis(4-aminobenzyl) Urea, 1,3-bis(4-aminophenethyl)urea, 1,1-bis(4-aminophenyl)cyclohexane, α,α'-bis(4-aminophenyl) )-1,4-diisopropylbenzene, 9,9-bis(4-aminophenyl)anthracene, 2,2-bis(3-aminophenyl)hexafluoropropane, 2,2-dual ( 4-aminophenyl)hexafluoropropane, 4,4'-diaminodiphenylamine, 2,4-diaminodiphenylamine, 1,8-diaminonaphthalene, 1,5-di Amino naphthalene, 1,5-diamino hydrazine, 1,3-diamino hydrazine, 1,6-diamino hydrazine, 1,8-diamino hydrazine, 2,7-diamino hydrazine, 1,3-bis(4-aminophenyl)tetramethyldioxane, benzidine, 2,2'-dimethylbenzidine, 1,2-bis(4-aminophenyl)ethane , 1,3-bis(4-aminophenyl)propane, 1,4-bis(4-aminophenyl)butane, 1,5-bis(4-aminophenyl)pentane, 1, 6-bis(4-aminophenyl)hexane, 1,7-bis(4-aminophenyl)heptane, 1,8-bis(4-aminophenyl)octane, 1,9- Bis(4-aminophenyl)decane, 1,10-bis(4-aminophenyl)decane, 1,3-bis(4-aminophenoxy)propane, 1,4-double ( 4-aminophenoxy)butane, 1,5-bis(4-aminophenoxy)pentane, 1,6-bis(4-aminophenoxy)hexane, 1,7-double (4-aminophenoxy)heptane, 1,8-bis(4-aminobenzene Oxy)octane, 1,9-bis(4-aminophenoxy)decane, 1,10-bis(4-aminophenoxy)decane, bis(4-aminophenyl)propane - 1,3-dioate, bis(4-aminophenyl)butane-1,4-dicarboxylate, bis(4-aminophenyl)pentane-1,5- Dicarboxylate, bis(4-aminophenyl)hexane-1,6-dicarboxylate, bis(4-aminophenyl)heptane-1,7-dicarboxylate, di(4) -aminophenyl)octane-1,8-dicarboxylate, bis(4-aminophenyl)decane-1,9-dicarboxylate, bis(4-aminophenyl)decane -1,10-dicarboxylate, 1,3-bis[4-(4-aminophenoxy)phenoxy]propane, 1,4-bis[4-(4-aminophenoxy) Phenoxy]butane, 1,5-double [4-(4-Aminophenoxy)phenoxy]pentane, 1,6-bis[4-(4-aminophenoxy)phenoxy]hexane, 1,7-bis[4 -(4-Aminophenoxy)phenoxy]heptane, 1,8-bis[4-(4-aminophenoxy)phenoxy]octane, 1,9-bis[4-( 4-aminophenoxy)phenoxy]nonane, 1,10-bis[4-(4-aminophenoxy)phenoxy]decane, and the like.

Examples of the heterocyclic diamine include 2,6-diaminopyridine, 2,4-diaminopyridine, 2,4-diamino-1,3,5-triazine, 2,7-di Aminodibenzofuran, 3,6-diaminocarbazole, 2,4-diamino-6-isopropyl-1,3,5-triazine, 2,5-bis(4-amino Phenyl)-1,3,4-oxadiazole and the like.

Examples of the aliphatic diamines include 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1, 6-Diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminodecane, 1,10-diaminodecane, 1, 3-diamino-2,2-dimethylpropane, 1,6-diamino-2,5-dimethylhexane, 1,7-diamino-2,5-dimethylheptane 1,7-Diamino-4,4-dimethylheptane, 1,7-diamino-3-methylheptane, 1,9-diamino-5-methylheptane, 1 , 12-diaminododecane, 1,18-diaminooctadecane, 1,2-bis(3-aminopropoxy)ethane, and the like.

Examples of the aromatic-aliphatic diamine include a diamine represented by the formula [3].

H ₂ N-Ar'-R ⁵ -NH-R ⁶ [3]

In the formula [3], Ar' is a phenyl or anthracene group, and R ⁵ is a C 1 to 5, preferably 1 to 3 alkyl group, and the R ⁶ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. The group is preferably a hydrogen atom or a methyl group.

Specific examples of the diamine represented by the formula [3] include 3-aminobenzylamine, 4-aminobenzylamine, 3-amino-N-methylbenzylamine, 4-amino-N-methylbenzylamine, 3-aminophenethylamine, 4-aminophenethylethyl Amine, 3-amino-N-methylphenethylamine, 4-amino-N-methylphenethylamine, 3-(3-aminopropyl)aniline, 4-(3-aminopropyl Aniline, 3-(3-methylaminopropyl)aniline, 4-(3-methylaminopropyl)aniline, 3-(4-aminobutyl)aniline, 4-(4-amine Benzyl)aniline, 3-(4-methylaminobutyl)aniline, 4-(4-methylaminobutyl)aniline, 3-(5-aminopentyl)aniline, 4-(5 -aminopentyl)aniline, 3-(5-methylaminopentyl)aniline, 4-(5-methylaminopentyl)aniline, 2-(6-aminonaphthyl)methylamine, 3-(6-aminonaphthyl)methylamine, 2-(6-aminonaphthyl)ethylamine, 3-(6-aminonaphthyl)ethylamine, and the like.

<tetracarboxylic dianhydride component>

In the present invention, the tetracarboxylic dianhydride component to be reacted with the diamine component is not particularly limited, and one type may be used or two or more types of tetracarboxylic dianhydride may be used in combination.

The tetracarboxylic dianhydride which reacts with the diamine component is preferably a tetracarboxylic dianhydride having an alicyclic structure or an aliphatic structure from the viewpoint of further increasing the voltage holding ratio of the liquid crystal cell.

Examples of the tetracarboxylic dianhydride having an alicyclic structure or an aliphatic structure include 1,2,3,4-cyclobutanetetracarboxylic dianhydride and 1,2-dimethyl-1,2,3,4. - cyclobutane tetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2 , 3,4-cyclobutane tetracarboxylic dianhydride, 1,2,3,4-cyclopentane tetracarboxylic dianhydride, 2,3,4,5-tetrahydrofuran tetracarboxylic acid Anhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,4-dicarboxy-1-cyclohexylsuccinic dianhydride, 3,4-dicarboxy-1,2,3,4- Tetrahydro-1-naphthalene succinic dianhydride, [4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic anhydride], 1 , 2,3,4-butane tetracarboxylic dianhydride, bicyclo[3,3,0]octane-2,4,6,8-tetracarboxylic dianhydride, 3,3',4,4'- Dicyclohexyltetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, cis-3,7-dibutylcyclooctane-1,5-diene-1,2,5, 6-tetracarboxylic dianhydride, tricyclo[4.2.1.02,5]decane-3,4,7,8-tetracarboxylic acid-3,4:7,8-dianhydride, hexacyclo[6.6.0.12, 7.03, 6.19, 14.010, 13] hexadecane-4,5,11,12-tetracarboxylic acid-4,5:11,12-dianhydride and the like. Among them, in particular, 1,2,3,4-cyclobutanetetracarboxylic dianhydride is preferred because an alignment film having excellent liquid crystal alignment property can be obtained.

Further, when aromatic tetracarboxylic dianhydride is used in combination, the liquid crystal alignment property is improved, and the accumulated charge of the liquid crystal cell can be quickly eliminated. Examples of the aromatic tetracarboxylic dianhydride include pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, and 2,2',3,3'-biphenyltetra Carboxylic dianhydride, 2,3,3',4-biphenyltetracarboxylic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 2,3,3', 4-benzophenone tetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl)ether dianhydride, bis(3,4-dicarboxyphenyl)ruthenic anhydride, 1,2,5,6- Naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 4,4'-(hexafluoroisopropylidene) diphthalic anhydride, and the like. Among them, pyromellitic dianhydride is particularly preferred.

The tetracarboxylic acid having an alicyclic structure or an aliphatic structure is preferably a balance between the solubility of the obtained polyamic acid or polyimine, the alignment of the liquid crystal, the voltage holding ratio, and the accumulated charge. The combination of dianhydride and aromatic tetracarboxylic dianhydride, and the ratio of the former/the latter to the molar ratio Preferably, it is 90/10~50/50, more preferably 80/20~60/40.

<Manufacture of polyamic acid and polyimine]

As the polyamic acid used in the present invention, a known polymerization method can be used. In general, a method of reacting a tetracarboxylic dianhydride component with a diamine component in an organic solvent. The reaction of the tetracarboxylic dianhydride with the diamine is relatively easy to carry out in an organic solvent, and no by-products are formed, which is preferable in this respect.

The organic solvent to be used at this time is not particularly limited as long as it is a polylysine which can be produced by dissolution. The following specific examples are mentioned.

N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 1,3-dimethyl-2- Imidazolinone, N-methylcaprolactam, dimethyl hydrazine, tetramethyl urea, pyridine, dimethyl hydrazine, hexamethylarylene, γ-butyrolactone, isopropanol, methoxy Methyl pentanol, dipentene, ethyl amyl ketone, methyl decyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, methyl cellulose, ethyl cellulose , methyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether , ethylene glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethyl Diol dimethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol Monoacetate monopropyl ether, 3-methyl-3-methoxybutyl Acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl Butyl ether, diisobutylene, pentyl acetate, butyl butyrate, dibutyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, dioxane, n-hexane, n -Pentane, n-octane, diethyl ether, cyclohexanone, ethylene carbonate, propylene carbonate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl acetate , methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid , 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, diglyme, 4-hydroxy-4-methyl-2-pentanone, etc. . These may be used alone or in combination. Further, even a solvent which does not dissolve polylysine may be used in the above solvent insofar as the produced polyamine does not precipitate. Further, since the water in the organic solvent hinders the polymerization reaction and causes hydrolysis of the produced polylysine, it is preferred that the organic solvent be dried as much as possible.

A method of reacting a tetracarboxylic dianhydride with a diamine in an organic solvent, and stirring a solution in which a diamine is dispersed or dissolved in an organic solvent, and dispersing or dissolving the tetracarboxylic dianhydride directly or in an organic solvent The method of adding, and conversely, the method of adding a diamine to the solution which disperse|dissolved or melt|dissolved tetracarboxylic-acid dianhydride in an organic solvent, the method of mutually adding a tetracarboxylic dianhydride and a diamine, etc. Any method. Further, when the tetracarboxylic dianhydride or the diamine is formed of a plurality of compounds, the reaction may be carried out in a state of being mixed in advance, or may be individually reacted in order, or the individual low molecular weight bodies may be further mixed. The reaction is carried out as a high molecular weight body.

The temperature at which the polyamic acid is synthesized may be any temperature from -20 ° C to 150 ° C, but preferably in the range of from -5 ° C to 100 ° C. In addition, the reaction can be It is carried out at any concentration, but since the concentration is too low, it becomes difficult to obtain a polymer having a high molecular weight. When the concentration is too high, the viscosity of the reaction liquid becomes too high, making uniform stirring difficult, and therefore it is preferably 1~ 50% by mass, more preferably 5 to 30% by mass. The initial stage of the reaction can be carried out at a high concentration, and then an organic solvent is added.

In the synthesis reaction of polyamic acid, the ratio of the molar number of the diamine component to the molar number of the tetracarboxylic dianhydride is preferably 0.8 to 1.2. As with the general polycondensation reaction, the closer the molar ratio is to 1.0, the larger the molecular weight of the produced polylysine becomes.

The polyimine used in the present invention is a polyimine obtained by subjecting the polyamic acid to dehydration ring closure, and can be used as a polymer for obtaining a liquid crystal alignment film.

In the polyimine used in the present invention, the dehydration ring closure ratio (the imidization ratio) of the valine group is not necessarily 100%, and may be arbitrarily adjusted in accordance with the use or purpose.

The method for carrying out hydrazine imidization of poly-proline is exemplified by thermal imidization of a solution of poly-proline, and imidization of a catalyst by adding a catalyst to a solution of poly-proline .

The temperature at which the polyaminic acid is thermally imidated in the solution is from 100 ° C to 400 ° C, preferably from 120 ° C to 250 ° C, and the water produced by the ruthenium imidization reaction is excluded from the system. .

The catalyst of the poly-proline is imidized, and a basic catalyst and an acid anhydride may be added to the solution of the poly-proline, and the mixture is stirred at -20 ° C to 250 ° C, preferably 0 to 180 ° C. The amount of alkaline catalyst is 0.5~30 moles of proline group. The ratio is preferably 2 to 20 moles, and the amount of the acid anhydride is 1 to 50 moles, preferably 3 to 30 moles, of the prolyl group.

Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine. Among them, pyridine is preferred because it has an appropriate basicity for carrying out the reaction. Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, and benzenetetracarboxylic anhydride. When an acid anhydride is used, purification after completion of the reaction becomes easier, which is preferable. The imidization ratio of the ruthenium imidized by the catalyst can be controlled by adjusting the amount of the catalyst, the reaction temperature, and the reaction time.

The ruthenium imidization ratio of the polyimine used in the liquid crystal alignment agent of the present invention is not particularly limited, and the sulfhydrylation ratio is preferably 40 to 90% from a liquid crystal alignment film which can obtain a higher voltage holding ratio. More preferably 50~90%, especially good 60~90%.

When the polymer component is recovered from the reaction solution of polyglycine or polyimine, the reaction solution may be introduced into a weak solvent to form a precipitate. Examples of the weak solvent used for precipitation include methanol, acetone, hexane, butyl cellulose, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, water, and the like. The polymer which is precipitated in a weak solvent is recovered by filtration, and dried at normal temperature or under heat at normal pressure or reduced pressure. In addition, the precipitate-recovered polymer is redissolved in an organic solvent, and the re-precipitation recovery operation is repeated 2 to 10 times to reduce impurities in the polymer. In the weak solvent at this time, when three or more kinds of weak solvents such as alcohols, ketones, and hydrocarbons are used, the purification efficiency can be further improved, which is preferable.

The molecular weight of the polyamic acid and the polyimine used in the present invention, when considering the strength of the coating film, the workability at the time of formation of the coating film, and the uniformity of the coating film, The weight average molecular weight measured by a GPC (Gel Permeation Chromatography) method is preferably 5,000 to 1,000,000, more preferably 10,000 to 150,000.

<Liquid alignment agent>

The liquid crystal alignment agent of the present invention is a coating liquid for a liquid crystal alignment film, and its main component is a resin component for forming a resin film and an organic solvent for dissolving the resin component. In the present invention, the resin component is a resin component containing polyamic acid and/or polyimine. In this case, the content of the resin component is 1 to 20% by mass, preferably 2 to 10% by mass.

In the present invention, the resin component may be a diamine component that reacts with tetracarboxylic dianhydride, and a polymer (hereinafter also referred to as a specific polymer) of all the specific diamines 1 and 2 may be used, or may be contained. Other polymers of the specific diamines 1, 2 are used. The content of the specific polymer in the resin component is preferably from 0.5 to 15% by mass, preferably from 1 to 10% by mass.

The organic solvent in which the resin component is dissolved is not particularly limited. Specific examples thereof include N,N'-dimethylformamide, N,N'-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, 2-pyrrolidone, N-ethylpyrrolidone, N-vinylpyrrolidone, dimethyl hydrazine, tetramethylurea, pyridine, dimethyl hydrazine, hexamethylarylene, γ-butyrolactone, 1,3-dimethyl- 2-imidazolidinone, dipentene, ethyl amyl ketone, methyl decyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, cyclohexanone, ethylene carbonate, Propylene carbonate, diglyme, 4-hydroxy-4-methyl-2-pentanone, and the like. These solvents can be used in combination of two or more types.

When the polyimine is dissolved in an organic solvent, heating can be performed in order to promote dissolution of the polyimide. When the temperature of the heating is too high, the molecular weight of the polyimine is lowered, so the temperature is preferably 30 to 100 °C. The concentration of the solution of the specific polyimine is not particularly limited, and it is easy to uniformly mix with the specific amine, so the concentration of the specific polyimine in the solution is preferably from 1 to 20% by mass, more preferably from 3 to 15% by mass. Particularly preferred is 3 to 10% by mass.

The liquid crystal alignment agent of the present invention may contain components other than the above. For example, a solvent or a compound which improves the film thickness uniformity or surface smoothness when the liquid crystal alignment agent is applied, and a compound which improves the adhesion between the liquid crystal alignment film and the substrate may be contained.

Specific examples of the solvent (weak solvent) for increasing the uniformity of the film thickness or the surface smoothness include the following.

For example, isopropyl alcohol, methoxymethylpentanol, methyl cellosolve, ethyl cellosolve, butyl cellulolytic, methyl cellosolve acetate, ethyl cellosolve acetate, and butyl Kikabi alcohol, ethyl carbitol, ethyl carbitol acetate, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol Monoacetate, propylene glycol monomethyl ether, propylene glycol-tert-butyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, Dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl 3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, pentyl acetate, Butyl butyrate, dibutyl ether, diisobutyl ketone, methyl Cyclohexene, propyl ether, dihexyl ether, n-hexane, n-pentane, n-octane, diethyl ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate , propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3- Ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, 1-methoxy-2-propanol, 1-ethoxyl 2-propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanol, propylene glycol monoacetate, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2- Acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2-(2-ethoxypropoxy)propanol, methyl lactate, ethyl lactate, n-propyl lactate, lactic acid A solvent having a low surface tension such as n-butyl ester or isoamyl lactate.

Among these, butyl cellosolve, propylene glycol monomethyl ether, propylene glycol monobutyl ether, and ethyl lactate are more preferable.

These weak solvents can be used in combination of one type or plural types. When the solvent is used as described above, it is preferably from 5 to 80% by mass, more preferably from 20 to 60% by mass, based on the total amount of the solvent contained in the liquid crystal alignment agent.

Examples of the compound which improves the uniformity of the film thickness or the surface smoothness include a fluorine-based surfactant, a rhodium-based surfactant, and a nonionic surfactant.

More specifically, for example, EFTOP EF301, EF303, EF352 (trade name of TOHKEM PRODUCTS), Megafac F171, F173, R-30 (product name of Dainippon Ink Co., Ltd.), Fluorad FC430, FC431 (manufactured by Sumitomo 3M Co., Ltd.), Asahiguard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (product name of Asahi Glass Co., Ltd.). The use ratio of the surfactant is preferably 0.01 to 2 parts by mass, more preferably 0.01 to 1 part by mass, per 100 parts by mass of the resin component contained in the liquid crystal alignment agent.

Specific examples of the compound which improves the adhesion between the liquid crystal alignment film and the substrate include those having a functional decane or a compound containing an epoxy group.

For example, 3-aminopropyltrimethoxydecane, 3-aminopropyltriethoxydecane, 2-aminopropyltrimethoxydecane, 2-aminopropyltriethoxydecane, N -(2-Aminoethyl)-3-aminopropyltrimethoxydecane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxydecane, 3-ureido Propyltrimethoxydecane, 3-ureidopropyltriethoxydecane, N-ethoxycarbonyl-3-aminopropyltrimethoxydecane, N-ethoxycarbonyl-3-aminopropyl Triethoxy decane, N-triethoxymethane alkyl propyl triethylene triamine, N-trimethoxymethyl decyl propyl triethylene triamine, 10-trimethoxymethyl decyl-1, 4, 7-Triazadecane, 10-triethoxycarbamido-1,4,7-triazadecane, 9-trimethoxycarbamilide-3,6-diazepine acetic acid Ester, 9-triethoxycarbamido-3,6-diazaindolyl acetate, N-benzyl-3-aminopropyltrimethoxydecane, N-benzyl-3-amino Propyltriethoxydecane, N-phenyl-3-aminopropyltrimethoxydecane, N-phenyl-3-aminopropyltriethoxydecane, N-bis(oxyethylene)-3 -Aminopropyltrimethoxydecane, N-double ( Ethylene)-3-aminopropyltriethoxydecane, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, poly Propylene glycol diepoxypropyl ether, neopentyl Alcohol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, 2,2-dibromo neopentyl glycol diglycidyl ether, 1,3,5 ,6-tetraepoxypropyl-2,4-hexanediol, N,N,N',N'-tetraepoxypropyl-m-xylenediamine, 1,3-bis(N,N- Diglycidylaminomethyl)cyclohexane, N,N,N',N'-tetraepoxypropyl-4, 4'-diaminodiphenylmethane, and the like.

When the compound to be adhered to the substrate is used, it is preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, per 100 parts by mass of the resin component contained in the liquid crystal alignment agent. When the amount is less than 0.1 part by mass, the effect of improving the adhesion cannot be expected, and when it is more than 30 parts by mass, the alignment of the liquid crystal may be deteriorated.

In the liquid crystal alignment agent of the present invention, in addition to the above, a dielectric or a conductive material for changing the electrical properties such as dielectric constant or conductivity of the liquid crystal alignment film, and a hardness of the film when the liquid crystal alignment film is used may be added. A cross-linking compound for the purpose of compactness.

The concentration of the solid component in the liquid crystal alignment agent of the present invention is preferably changed depending on the film thickness of the liquid crystal alignment film to be used. However, it is preferred to form a film having no defects and to obtain a suitable film thickness as the liquid crystal alignment film. 1 to 20% by mass, more preferably 2 to 10% by mass.

<Liquid alignment film. Liquid crystal display element>

The liquid crystal alignment agent of the present invention is applied to a substrate, and after firing, it is subjected to alignment treatment by rubbing treatment or light irradiation, or when it is used for vertical alignment or the like, it can be used as a liquid crystal alignment film without alignment treatment. In this case, the substrate to be used is not particularly limited as long as it is a substrate having high transparency, and glass can be used. A glass substrate, a plastic substrate such as an acrylic substrate or a polycarbonate substrate, or the like. Moreover, from the viewpoint of simplification of the process, it is preferred to use a substrate on which an ITO electrode or the like for driving a liquid crystal is formed. Further, in the case of a reflective liquid crystal display device, when it is only a single-sided substrate, an opaque material such as a germanium wafer may be used, and in this case, a material that reflects light such as aluminum may be used as the electrode.

The coating method of the liquid crystal alignment agent is not particularly limited, and industrially, screen printing, lithography, letterpress printing, inkjet, or the like is generally used. Other coating methods include, for example, dipping, roll coating, slit coating, spin coating, and the like, and such methods may be used depending on the purpose.

After the liquid crystal alignment agent is applied onto the substrate and fired, the solvent can be evaporated at 50 to 200 ° C, preferably 80 to 150 ° C by a heating means such as a hot plate to form a coating film. When the thickness of the coating film after firing is too thick, it is disadvantageous in terms of power consumption of the liquid crystal display element. If the thickness of the coating film is too thin, the reliability of the liquid crystal display element may be lowered. Therefore, it is preferably 5 to 300 nm, more preferably 10 or less. ~100nm. When the liquid crystal is aligned horizontally or obliquely, the coating film after firing is treated by rubbing or polarized ultraviolet irradiation or the like.

In the liquid crystal display device of the present invention, after the substrate having the liquid crystal alignment film is obtained by using the liquid crystal alignment agent of the present invention by the above method, a liquid crystal cell is produced by a known method, and then it is used as a component.

In the case of an example of liquid crystal cell formation, for example, a pair of substrates on which a liquid crystal alignment film is formed is prepared, and a spacer is dispersed on a liquid crystal alignment film of one of the substrates, so that the liquid crystal alignment film surface is inside, and the other is bonded to the other. The substrate is then injected into the liquid crystal under reduced pressure and sealed, or a method in which the liquid crystal is dropped on the liquid crystal alignment film surface on which the spacer is dispersed, and the substrate is bonded and closed. The thickness of the spacer at this time is preferably from 1 to 30 μm, more preferably from 2 to 10 μm.

The liquid crystal display element produced by using the liquid crystal alignment agent of the present invention is a liquid crystal display element which can reduce display unevenness caused by uneven alignment of liquid crystals generated by the ODF method.

[Examples]

The invention will be described in more detail below with reference to examples but the invention is not limited by these examples. The abbreviations and measurement methods of the compounds used below are as follows.

(acid dianhydride)

BODA: Bicyclo[3,3,0]octane-2,4,6,8-tetracarboxylic dianhydride.

CBDA: 1,2,3,4-cyclobutane tetracarboxylic dianhydride.

(diamine)

<additive>

3AMP: 3-pyridine methylamine (Picolylamine).

<solvent>

NMP: N-methyl-2-pyrrolidone.

BCS: butyl cellosolve.

<Polymerimide molecular weight measurement>

The molecular weight measurement conditions of the polyimine are as follows.

Device: SENSHU Scientific Co., Ltd. Normal temperature gel permeation chromatography (GPC) device (SSC-7200),

Column: Shodex pipe column (KD-803, KD-805)

Column temperature: 50 ° C

Dissolution: N,N'-dimethylformamide (additive is lithium bromide-hydrate (LiBr.H ₂ O) 30 mmol/L, phosphoric acid. anhydrous crystal (o-phosphoric acid) 30 mmol/L, tetrahydrofuran (THF) 10 ml /L)

Flow rate: 1.0ml/min

Standard sample for the production of calibration lines: TSK standard polyethylene oxide (molecular weight of about 9,000, 150,000, 100,000, 30,000) made by Tosoh Corporation and polyethylene glycol (polymerized by the company of polymer company) (molecular weight of about 12,000, 4,000, 1,000).

<Measurement of sulfhydrylation rate>

20 mg of polyimine powder was placed in an NMR sample tube (NMR sample tube standard Φ5 manufactured by Kusano Scientific Co., Ltd.), and 1.0 ml of dimethyl hydrazine (DMSO-d ₆ , 0.05% TMS mixture) was added thereto, and applied. Ultrasonic waves make it completely soluble. This solution was measured for proton NMR at 500 MHz using an NMR measuring instrument (JNW-ECA500) manufactured by JEOL Ltd. The sulfhydrylation rate is determined by the protons from the unaltered structure before and after the imidization as the reference proton. The peak value of this proton is used and the protons from the NH group of proline are present near 9.5 to 10.0 ppm. The peak value is calculated according to the following formula. Further, in the following formula, x is a proton peak product value derived from the NH group of proline, y is a peak integrated value of the reference proton, and α is a polyglycine (the imidization ratio is 0%). The ratio of the number of reference protons to one proton of the NH group of valine.

醯 imidization rate (%) = (1-α.x/y) × 100

<Production of liquid crystal cell for liquid crystal alignment unevenness evaluation>

The liquid crystal alignment agent was spin-coated on an ITO surface of an ITO electrode substrate having an ITO electrode pattern having a pixel size of 100 μm × 300 μm and a line/space of 5 μm, and dried on a hot plate at 80 ° C for 90 seconds, and then used. The hot air circulating oven at 200 ° C was fired for 20 minutes to form a liquid crystal alignment film having a film thickness of 100 nm.

Further, a liquid crystal alignment agent was spin-coated on an ITO surface of an ITO electrode substrate (not formed with an electrode pattern) having a photosensitive spacer (Photo-Spacer) of 3.3 μm, and dried using a hot plate at 80 ° C for 90 seconds. It is baked in a hot air circulating oven at 200 ° C for 20 minutes to form a film thickness. 100 nm liquid crystal alignment film.

On the liquid crystal alignment film of one of the two substrates, a sealant (solvent type photocuring type) was applied using a dispenser device (manufactured by Musashi-Engineering Co., Ltd., FAD630), and a negative liquid crystal MLC- was used for PSA. 3023 (trade name manufactured by Merk Co., Ltd.) dropped 6 points on the liquid crystal alignment film. Next, the substrate is bonded to another substrate in a vacuum, and the sealing material is UV-cured to fill the liquid crystal.

Then, in a state where a DC voltage of 15 V was applied, a filter of 325 nm or less was cut and irradiated with UV of 15 J/cm ^{2 to} prepare a liquid crystal cell for liquid crystal alignment unevenness evaluation.

<Evaluation of uneven liquid crystal alignment>

The liquid crystal cell produced under the above conditions was placed between two polarizing plates in which the polarization axes were arranged orthogonally, and the backlight was lit. Then, for the liquid crystal cell, an AC voltage of 4 Vpp was applied. The liquid crystal cells from the start of the addition to 3 minutes were observed, and the liquid crystal alignment unevenness was visually evaluated. At this time, if the droplets of the liquid crystal were not found (uneven alignment), it was judged as "good", and when the trace was observed, it was judged as "poor".

<Production of liquid crystal cell for voltage retention rate evaluation>

The liquid crystal alignment agent was spin-coated on an ITO surface of an ITO electrode substrate having an ITO electrode pattern having a pixel size of 100 μm × 300 μm and a line/space of 5 μm, and dried on a hot plate at 80 ° C for 90 seconds, and then used. 200 ° C hot air circulating oven for 20 minutes to form a film thickness 100 nm liquid crystal alignment film.

Further, the liquid crystal alignment agent was spin-coated on the ITO surface on which the electrode pattern was not formed, and dried using a hot plate at 80 ° C for 90 seconds, and then fired in a hot air circulating oven at 200 ° C for 20 minutes to form a liquid crystal having a film thickness of 100 nm. Orientation film.

Regarding the above two substrates, a liquid crystal alignment film of one of the substrates was sprinkled with a bead spacer of 4 μm, and then a sealant (solvent type thermosetting epoxy resin) was printed thereon. Next, the surface of the other substrate on the side where the liquid crystal alignment film is formed is set to the inside, and after bonding to the previous substrate, the sealing agent is cured to form an empty cell.

MLC-3023 was injected into the empty cell by a vacuum injection method to prepare a liquid crystal cell. The voltage holding ratio (VHR) of this liquid crystal cell was measured.

Then, in the state in which a DC voltage of 15 V is applied to the liquid crystal cell, and then a DC voltage of 15 V is applied, a UV filter of 15 J/cm ² is irradiated by a filter having a barrier of 325 nm or less, and voltage holding ratio evaluation is performed. Use liquid crystal cells.

<Evaluation of voltage retention rate>

In the above-mentioned liquid crystal cell for voltage holding rate evaluation, after applying a voltage of 1 V for 60 μs in a hot air circulating oven of 60 ° C, the voltage after 1667 msec was measured, and the voltage was maintained as a voltage holding ratio. The measurement of the voltage holding ratio was performed using VHR-1 manufactured by Dongyang Technic Co., Ltd.

(Example 1)

BODA (3.15g, 12.6mmol), DA-1 (4.00g, 10.5mmol), DA-2 (0.45g, 4.2mmol), DA-3 (2.46g, 6.30mmol) were dissolved in NMP (40.2g) After reacting at 60 ° C for 3 hours, CBDA (1.58 g, 8.06 mmol) and NMP (6.4 g) were added, and the reaction was allowed to stand at 40 ° C for 10 hours to obtain a polyaminic acid solution.

After adding NMP to the polyamic acid solution (25.0 g) and diluting it to 6.5% by mass, acetic anhydride (4.58 g) and pyridine (3.55 g) as a ruthenium amide catalyst were added and reacted at 80 ° C. 4 hours. This reaction solution was poured into methanol (300 g), and the resulting precipitate was filtered. The precipitate was washed with methanol, and dried under reduced pressure at 100 ° C to obtain a polyimine powder A. The polyamidimide had a ruthenium iodide ratio of 73%, a number average molecular weight of 16,600, and a weight average molecular weight of 73,800.

To the obtained polyimine powder A (3.0 g), NMP (29.0 g) was added, and the mixture was stirred at 70 ° C for 12 hours to dissolve. To the solution, 3.0 g of 3AMP (1 mass% NMP solution) and BCS (15.0 g) were added, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal alignment agent A1.

(Example 2)

BODA (2.55 g, 10.2 mmol), DA-1 (3.23 g, 12.9 mmol), DA-2 (0.37 g, 3.4 mmol), DA-4 (2.44 g, 5.10 mmol) were dissolved in NMP (34.4 g) After reacting at 60 ° C for 3 hours, CBDA (1.28 g, 6.53 mmol) and NMP (5.2 g) were added, and the reaction was carried out at 40 ° C for 10 hours to obtain polylysine solution. liquid.

After adding NMP to the polyamic acid solution (25.0 g) and diluting it to 6.5% by mass, acetic anhydride (4.37 g) and pyridine (3.39 g) as a ruthenium amide catalyst were added and allowed to stand at 80 ° C. Reaction for 4 hours. This reaction solution was poured into methanol (300 g), and the resulting precipitate was filtered. The precipitate was washed with methanol and dried under reduced pressure at 100 ° C to obtain a polyimine powder B. The polyamidimide had a ruthenium iodide ratio of 73%, a number average molecular weight of 13,700, and a weight average molecular weight of 48,600.

NMP (29.0 g) was added to the obtained polyimine powder B (3.0 g), and the mixture was stirred at 70 ° C for 12 hours to dissolve. To the solution, 3.0 g of 3AMP (1 mass% NMP solution) and BCS (15.0 g) were added, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal alignment agent B1.

(Comparative Example 1)

BODA (3.15g, 12.6mmol), DA-1 (4.00g, 10.5mmol), DA-2 (0.45g, 4.2mmol), DA-5 (0.96g, 6.3mmol) were dissolved in NMP (34.2g) After reacting at 60 ° C for 3 hours, CBDA (1.61 g, 8.21 mmol) and NMP (6.4 g) were added, and the mixture was reacted at 40 ° C for 10 hours to obtain a polyaminic acid solution.

In this polyamic acid solution (25.0 g), NMP was added and diluted to 6.5% by mass, and then acetic anhydride (5.25 g) and pyridine (4.07 g) as a ruthenium catalyst were added, and the mixture was allowed to stand at 80 ° C. Reaction for 4 hours. This reaction solution was poured into methanol (300 g), and the resulting precipitate was filtered. The precipitate was washed with methanol and dried under reduced pressure at 100 ° C to obtain a polyimine powder. End C. The polyimine had a hydrazine imidation ratio of 72%, a number average molecular weight of 12,800, and a weight average molecular weight of 38,400.

To the obtained polyimine powder C (3.0 g), NMP (29.0 g) was added, and the mixture was stirred at 70 ° C for 12 hours to dissolve. To the solution, 3.0 g of 3AMP (1 mass% NMP solution) and BCS (15.0 g) were added, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal alignment agent C1.

(Comparative Example 2)

BODA (15.01g, 59.99mmol), DA-1 (19.03g, 50.00mmol), DA-2 (2.16g, 20.0mmol), DA-6 (7.27g, 30.0mmol) were dissolved in NMP (173.9g) After reacting at 60 ° C for 3 hours, CBDA (7.75 g, 39.5 mmol) and NMP (30.4 g) were added, and the mixture was reacted at 40 ° C for 10 hours to obtain a polyaminic acid solution.

In this polyamic acid solution (25.0 g), after adding NMP to 6.5% by mass, acetic anhydride (4.97 g) and pyridine (3.86 g) as a ruthenium amide catalyst were added, and the mixture was allowed to be at 80 ° C. Reaction for 4 hours. This reaction solution was poured into methanol (300 g), and the resulting precipitate was filtered. The precipitate was washed with methanol, and dried under reduced pressure at 100 ° C to obtain a polyimine powder D. The polyimine had a hydrazine imidation ratio of 72%, a number average molecular weight of 14,000, and a weight average molecular weight of 46,300.

NMP (29.0 g) was added to the obtained polyimine powder D (3.0 g), and the mixture was stirred at 70 ° C for 12 hours to dissolve. 3 AMP (1 mass % NMP solution) 3.0 g, BCS (15.0 g) was added to the solution, and it was added to the room. The mixture was stirred under heating for 5 hours to obtain a liquid crystal alignment agent D1.

Using the liquid crystal alignment agents obtained in the above-mentioned Examples 1 and 2 and Comparative Examples 1 and 2, the liquid crystal cell for liquid crystal alignment unevenness evaluation and the liquid crystal cell for voltage holding ratio evaluation were produced, and the liquid crystal alignment unevenness and voltage retention ratio were evaluated. . The results of the respective evaluations are shown in Tables 1 and 2.

From the results of the above Tables 1 and 2, it is understood that the liquid crystal alignment film obtained from the liquid crystal alignment agent of the example can reduce the liquid crystal which is generated in the liquid crystal cell when compared with the liquid crystal alignment film obtained from the liquid crystal alignment agent of the comparative example. The alignment is uneven and the voltage retention rate is high.

[Industrial availability]

The liquid crystal alignment film obtained by the liquid crystal alignment agent of the invention can reduce the display unevenness caused by the uneven alignment of the liquid crystal, and can be used for high definition liquid crystal TV, large or small display monitor, smart mobile phone, tablet computer ( A wide range of display elements such as tablets).

The entire disclosure of Japanese Patent Application No. 2015-254920, filed on Jan. 25,,,,,,,,,,,,,,

Claims (12)

A liquid crystal alignment agent comprising a polymer selected from the group consisting of a diamine component comprising a diamine having a crown ether structure and an aromatic ring and a diamine having a side chain exhibiting a pretilt angle of a liquid crystal. At least one of a group of polylysine obtained by reacting a tetracarboxylic dianhydride component and a polyamidimide of a ruthenium imide of the polyamic acid. The liquid crystal alignment agent of the first aspect of the invention, wherein the diamine having a crown ether structure and an aromatic ring is a diamine represented by the following formula [1], (X ¹ and X ² each independently represent a single bond or -(OCH ₂ CH ₂ ) _n -, n represents an integer of 1 to 4, and R ¹ represents any of the following structures) (R ² and R ⁴ each independently represent a single bond or an alkylene group having 1 to 5 carbon atoms, R ³ represents a single bond, a C 1 to 5 alkyl group or a carbonyl group, and X represents an aromatic ring). The liquid crystal alignment agent of claim 2, wherein X in the formula representing R ¹ is a benzene ring. The liquid crystal alignment agent according to any one of claims 1 to 3, wherein the diamine having a crown ether structure and an aromatic ring contains 10 to 80 mol% based on the diamine component. The liquid crystal alignment agent according to any one of claims 1 to 4, wherein the diamine having a side chain exhibiting a pretilt angle of the liquid crystal is a diamine represented by the following formula [1a], (X ₁ is selected from the group consisting of -O-, -CH ₂ O-, -COO-, -(CH ₂ ) _a - (a is an integer of 1 to 10), -NH-, -N(CH ₃ )-, - CONH-, -NHCO-, -OCO-, -CON(CH ₃ )-, -N(CH ₃ )CO-, or a divalent organic group of a single bond, X ₂ is selected from a single bond, or -(CH _{2 b} - (b is an integer of 1 to 10) of a divalent organic group, and X ₃ is selected from a single bond, -(CH ₂ ) _c - (c is an integer of 1 to 10), -O-, -NH- , -N(CH ₃ )-, -CONH-, -NHCO-, -CH ₂ O-, -COO-, -OCO-, -CON(CH ₃ )-, or -N(CH ₃ )CO- The valence organic group, X ₄ is a divalent cyclic group selected from a benzene ring, a cyclohexene ring or a heterocyclic ring, or a divalent organic group having a carbon number of 12 to 25 having a steroid skeleton, and any of the above cyclic groups The hydrogen atom may be selected from an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, or a fluorine-containing alkoxy group having 1 to 3 carbon atoms, or fluorine. Substituted by an atom, X ₅ represents a divalent cyclic group selected from a cyclohexane ring, a benzene ring, or a heterocyclic ring, and any hydrogen atom on the cyclic group may be selected from an alkyl group having 1 to 3 carbon atoms. , alkoxy group having 1 to 3 carbon atoms, fluorine-containing alkyl group having 1 to 3 carbon atoms, or fluorine-containing alkoxy group having 1 to 3 carbon atoms, and fluorine atom substituted, n-based integer of 0 to 4, X ₆ Carbon number 1~18 Alkyl group, a fluorinated alkyl group having a carbon number of 1 to 18 carbon atoms of an alkoxy group having 1 to 18 carbon atoms or a fluoroalkoxy hydrogen atom, m is an integer of 1 to 18 the line 1-4 of having). The liquid crystal alignment agent according to any one of claims 1 to 5, wherein the tetracarboxylic dianhydride component contains a tetracarboxylic dianhydride having an alicyclic structure or an aliphatic structure and an aromatic tetracarboxylic acid anhydride. The liquid crystal alignment agent according to any one of claims 1 to 5, wherein the diamine having a side chain exhibiting a pretilt angle of the liquid crystal is 10 to 80 mol% based on the diamine component. The liquid crystal alignment agent of claim 6 or 7, wherein the molar ratio of the tetracarboxylic dianhydride having an alicyclic structure or an aliphatic structure to the aromatic tetracarboxylic dianhydride is 90/10~ 50/50. The liquid crystal alignment agent according to any one of claims 1 to 6, wherein the polyamidene contained in the polymer has a sulfhydrylation ratio of 40 to 90%. A liquid crystal alignment film obtained by the liquid crystal alignment agent according to any one of claims 1 to 9. A liquid crystal display element comprising the liquid crystal alignment film of claim 10 of the patent application. The liquid crystal display element of claim 11, wherein the liquid crystal is filled in the liquid crystal cell by liquid crystal dropping (ODF).