WO2003005113A1

WO2003005113A1 - Liquid crystal alignment agent for vertical alignment of liquid crystal

Info

Publication number: WO2003005113A1
Application number: PCT/JP2002/006758
Authority: WO
Inventors: Toshiyuki Akiike; Masaki Obi; Tsuyoshi Hirai
Original assignee: Jsr Corporation
Priority date: 2001-07-03
Filing date: 2002-07-03
Publication date: 2003-01-16
Also published as: TW556030B; KR20030029852A; KR100842156B1; JP2003015135A

Abstract

A liquid crystal alignment agent for the vertical alignment of a liquid crystal which comprises a polymer having specific two types of amic acid recurring unit and an imidated recurring unit. The liquid crystal alignment agent is excellent in capability of aligning a liquid crystal vertically and is reduced with respect to the time required for erasing an afterimage, and thus can be suitably used for a liquid crystal display element of MVA type.

Description

Liquid crystal vertical alignment liquid crystal alignment agent

The present invention relates to a liquid crystal vertical alignment liquid crystal alignment agent. More specifically, the liquid crystal display is particularly suitable for the MVA (Mu1ti-doma inverticala 1 ig nment) type liquid crystal display element, because the liquid crystal display element has a short vertical orientation, printability, and a short after-image erasing time of the liquid crystal display element. The present invention relates to a vertical alignment liquid crystal light-directing agent.

Conventional technology

At present, as a liquid crystal display element, a liquid crystal alignment film made of polyamic acid, polyimide, or the like is formed on the surface of the substrate on which the transparent conductive film is provided, and a liquid crystal display element substrate is formed. A nematic liquid crystal layer with positive dielectric anisotropy is formed in the gap to form a sandwich structure cell, and the major axis of the liquid crystal molecules is continuously twisted 90 degrees from one substrate to the other. A TN type liquid crystal display element having a so-called TN (Twisted Negative) type liquid crystal cell is known. In addition, STN (Super Twisted Nematic) liquid crystal display elements and vertical alignment type liquid crystal display elements that have higher contrast than TN type liquid crystal display elements and are less dependent on the viewing angle have been developed. This STN-type liquid crystal display element uses a nematic liquid crystal blended with an optically active substance, a chiral agent, as the liquid crystal, and the long axis of the liquid crystal molecules is continuously twisted over 180 degrees between the substrates. This utilizes the birefringence effect caused by the above.

On the other hand, as described in "Liquid Crystal" Vol. 3 No. 2117 (1999) and JP-A-11-258605, a projection is formed on the ITO to control the alignment direction of the liquid crystal. A vertical alignment type liquid crystal display device called an MVA method has been proposed. The MVA-type liquid crystal display element is excellent in the manufacturing process, such as being excellent in viewing angle, contrast, etc., and requiring no rubbing treatment in forming a liquid crystal alignment film. As a liquid crystal alignment film suitable for the MVA method, The liquid crystal display element is required to have excellent performance such as excellent elimination time and a short afterimage erasing time. Disclosure of the invention

An object of the present invention is to provide a liquid crystal vertical alignment liquid crystal alignment agent which is excellent in vertical alignment of liquid crystal and has a short afterimage erasing time of a liquid crystal display element and is suitably used for an MVA type liquid crystal display element.

Still other objects and advantages of the present invention will become apparent from the following description. According to the present invention, the object and advantages of the present invention are as follows: (A) a repeating unit represented by the following formula (1-1); and (B) a repeating unit represented by the following formula (1-2). This is achieved by a liquid crystal vertical alignment liquid crystal aligning agent characterized by containing a polymer having:

(1)

Wherein, P ¹ is a tetravalent organic group, Q ¹ represents a divalent organic group _c

(1 -2)

In the formula, P ² is a tetravalent organic group, and Q ² is a divalent group represented by the following formula (Q-1) or the following formula (Q-2).

Wherein X ¹ is a single bond, —〇, —CO_, —COO—, —〇C〇-1, —NHC —1, CONH—, —S— or arylene, and R ¹ Is an alkyl group having 10 to 20 carbon atoms, a monovalent organic group having an alicyclic skeleton having 4 to 40 carbon atoms, or a monovalent organic group having a fluorine atom having 6 to 20 carbon atoms.

In the formula, X ² and X ³ are the same or different and are a single bond, —O—, —CO—, one C〇〇, one CO—, one NHC0—, one C0NH—, one S—, or an arylene group R ² is a divalent organic group having an alicyclic skeleton having 4 to 40 carbon atoms.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic view of an MVA type liquid crystal cell used in an embodiment of the present invention. Embodiment of the Invention

Hereinafter, the present invention will be described in detail.

The liquid crystal vertical alignment liquid crystal aligning agent of the present invention is constituted by dissolving the polymer component, preferably in an organic solvent. The polymer component in the present invention includes: (A) a polyamic acid having a repeating unit represented by the above formula (1-1) (hereinafter also referred to as “component (A)”); It contains an imidized polymer having a repeating unit represented by 1-2) (hereinafter, also referred to as “component (B)”), or ② (A) a repeating unit represented by the above formula (1-1) The block copolymer preferably contains a block copolymer comprising an acid acid prepolymer having units and (B) an imidoblepolymer having a repeating unit represented by the formula (1-2). It is preferable to be ①. . In the above ①, the polyamic acid of the component (A) is obtained by reacting tetracarboxylic dianhydride with diamine, and the imidized polymer of the component (B) is tetracarboxylic dianhydride and H ₂ N-Q ² - NH ₂ (wherein, Q ² is formula (I one 2) the same definition as) Jiamin (hereinafter also referred to as "specific Jiamin") having the structure represented by reacting the obtained The resulting polyamic acid is obtained by dehydration and ring closure.

(A) Polyamic acid

Specific examples of the tetracarboxylic dianhydride used in the synthesis of the polyamic acid as the component (A) include, for example, 1,2,3,4-cyclobutanetetracarboxylic dianhydride. Water, 1,2-dimethyl_1,2,3,4-cyclobutanetetrahydroluponate dihydrate, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarponic acid dihydrate 1,3-dichloro-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetrahydroluponic anhydride, 1 , 2,3,4-cyclopentanetetracarboxylic dianhydride,

1. 2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3,, 4,4'-dicyclohexyltetracarboxylic dianhydride, cis-1,3,7-dibutylcyclohexane 5-gen-1,2,5,6-tetracarboxylic dianhydride, 2,

3,5-tricarbonyloxypentylacetic acid dianhydride, 3,5,6-tricarbonyl-2-carboxynorpornanone 2: 3,5: 6-dianhydride, 2,3,4,

5-tetrahydrofurantetracarboxylic dianhydride, 1,3,3a, 4,5,9b-Hexahydro-5 (tetrahydro-1,2,5-dioxo-1-furanyl) 1-naphtho [1,2-c ] —Furan 1,3-dione, 1,3,3a, 4,5,9b-Hexahydro-15-methyl-15 (tetrahydro-1,2,5-dioxo-3_furanyl) 1-naphtho [1,2 — C] —furan-1,3-dione, 1,3,3a, 4,5,9b—hexahydro-5_ethyl_5 (tetrahydro_2,5-dioxo—3-furanyl) 1-naphtho [1, 2—c] One furan per 1,3-dione, 1,3,3a,

4,5,9 b-Hexahydro-7-methyl-5 (tetrahydro-2,5-dioxo-3-furanyl) 1-naphtho [1,2-c] 1-furan- 1,3-dione, 1,3,3a, 4,5,9 b-Hexahydro-1 7-ethyl-5 (tetrahydro-2,5-dioxo-3-furanyl) 1-naphtho [1,2-c] —furan-1,3-dione,

1. 3,3a, 4,5,9b-Hexahydro-18-methyl-15 (tetrahydro-2,5-dioxo-3-furanyl) 1-naphtho [1,2-c] —furan-1,3- Dione, 1,3,3a, 4,5,9b-Hexahydro-8-ethyl-5 (tetrahydro-1,2,5-dioxo-3-furanyl) 1-naphtho [1,2-c] —furan 1,3 —Dione, 1,3,3a, 4,5,9b—hexahydro-1,5,8-dimethyl-5 (tetrahydro-2,5-dioxo_3-furanyl) 1-naphtho [1,2-c] —furan-1 1,3-dione, 5- (2,5-dioxotetrahydrofural) 1,3-Methyl-3-cyclohexene-1,2-dicarboxylic dianhydride, bicyclo [2,2,2] oct-7-ene-1,2,3,5,6-tetracarboxylic dianhydride Compound, 3-oxabicyclo [3,2,1] octane-1,2,4-dione-6-spiro-13 '-(tetrahydrofuran-1', 5'-dione), represented by the following formulas (H) and (Π) Alicyclic tetracarboxylic dianhydride such as

In the formula, R ³ and R ⁶ represent a divalent organic group having an aromatic ring, R ⁴ and R ⁵ represent a hydrogen atom or an alkyl group, and a plurality of R ⁴ and R ⁵ are the same, respectively. But they may be different.

Aliphatic tetracarboxylic dianhydrides such as butane tetracarboxylic dianhydride; pyromellitic dianhydride, 3, 3,, 4, 4'-benzophenone tetracarboxylic dianhydride, 3, 3,, 4,4, -Biphenylsulfonetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-Naphthene lentetratetracarboxylic acid dianhydride 1,3,3,4,4,1-biphenylethertetracarboxylic dianhydride, 3,3,4,4, -dimethyldiphenylsilane tetracarboxylic dianhydride, 3,3,4,4 , -Tetraphenylsilanetetracarboxylic dianhydride, 1,2,3,4-furantetracarboxylic 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 difuranic dianhydride, 3, 3 ' , 4,4'-biphenyltetracarboxylic dianhydride, bis (phthalic acid) phenylphosphine oxide dianhydride, ρ-phenylene-bis (triphenylphthalic acid) dianhydride, m-phenylene Bis (triphenylphthalic acid) dianhydride, bis (triphenylphthalic acid) -1,4,4'-diphenyletheric anhydride, bis (triphenylphthalic acid) -1,4,4'-diphenylmethane dianhydride, ethylene Glycol bis (anhi) Drotrimellitate), propylene glycol-bis (anhydrotrimellitate), 1,4-butanediol / bis (anhydrotrimellitate), 1,6-hexanediol-bis (anhydrotrimellitate) , 1,8-octanediol-bis (anhydrotrimellitate), 2,2-bis (4-hydroxyphenyl) propane-bis (anhydrotrimellitate), represented by the following formulas (1) to (4) An aromatic tetracarboxylic dianhydride such as an aromatic tetracarboxylic dianhydride having a steroid skeleton represented can be mentioned. These are used alone or in combination of two or more.

: Of these, 1,2,3,4-cis dianhydride, 3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3 4-cyclopentanetetracarboxylic dianhydride, 2,3,5-tripropoxycyclopentylacetic dianhydride, 5- (2,5-dioxotetrahydrofural) -1,3-methyl-3-cyclohexene-1,1, 2-dicarboxylic dianhydride, cis-1,3,1-dibutylcyclohexyl 1,5-gen-1,2,5,6-tetracarboxylic dianhydride, 3,5,6 2-loo 2 _carpoxy norporanane 1: 2,3,5: 6-dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo_3-furanyl) Naft

[1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b_hexahydro-8-methyl-5_ (tetrahydro-2,5-dioxo-1-3-furanyl) Naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5,8-dimethyl-5- (tetrahydro-1,2,5-dioxo3 —Furanyl) 1-naphtho [1,2-c] furan-1,3-dione, bicyclo [2,2,2] —oct-7-ene—2,3,5,6-tetracarboxylic dianhydride , 3-oxabicyclo [3,2,1] octane-1,2,4-dione-6-spiro-1,3- (tetrahydrofuran-1,2 ', 5, dione), among the compounds represented by the above formula (II), Compounds represented by (5) to (7), compounds represented by the following formula (8) among compounds represented by the above formula (m), butanetetracarboxylic dianhydride, pyromellitic dianhydride Thing, 3 3,, 4,4'-Benzophenonetetracarponic dianhydride, 3,3 ', 4,4'-Piphenylsulfonetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetra Carboxylic dianhydride is preferred from the viewpoint that good liquid crystal alignment and electrical properties can be exhibited. These tetracarboxylic dianhydrides are used alone or in combination of two or more.

Examples of the diamine used for the synthesis of the polyamic acid as the component (A) include p-phenylenediamine, m-phenylenediamine, 4,4, -diaminodiphenylmethane, 4,4, -diaminodiphenylethane, and 4 , 4 'diaminodiphenyl sulfide, 4,4, diaminodiphenyl sulfone, 2,2, -dimethyl-1,4,4' diaminobiphenyl, 3,3,1-dimethyl-4,4'-diaminobiphenyl, 4,4, Diaminobenzanilide, 4,4, -diaminodiphenyl ether, 1,5-diaminonaphthylene, 3,3-dimethyl-4,4, diamy Noviphenyl, 5-amino-1- (4,1-aminophenyl) 1,1,3,3-trimethylindane, 6-amino-11- (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) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoroprop mouthpan, 2,2-bis (4-aminophenyl) hexafluoropropane, 2,2-bis [4- (4-aminophenoxy) phenyl ] Sulfone, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 9,9-bis (4-aminophenoxy) benzene 1) 10-hydroanthracene, 2,7 diaminofluorene, 9,9 bis (4-aminophenyl) fluorene, 4,4, -methylenebis (2-chloroaniline), 2,2,5, 5, -tetrachloro-4,4, -diaminobiphenyl, 2,2, dichloro-4,4, diamino-5,5, dimethoxybiphenyl, 3,3 'dimethoxy-4,4'-diaminobiphenyl, 1,4,4,- (p-phenyleneisopropylidene) bisaniline, 4,4,1- (m-phenyleneisopropylidene) bisaniline, 2,2, -bis [4-1 (4-amino-1-2-trifluoromethylphenoxy) Phenyl] hexafluoropropane, 4,4, diamino-2,2'-bis (trifluoromethyl) biphenyl, 4,4,1-bis [(4-amino-2-trifluoromethyl) phenoxy] 1 year old K Furuo Robifueniru aromatics such Jiamin;

1,1-meta-xylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, 4,4 diamino heptamethylene diamine, 1, 4 diamino cyclohexane, isophorone diamine, tetrahydrodicyclopentene genylene diamine, hexahydro-4,7-tricyclo [6.2.1.0 ² ' ⁷ ] ', 4, 4, —methylenebis (cyclohexylamine) Aliphatic and cycloaliphatic diamines such as;

2,3-diaminopyridine, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 5,6-diamino-1,2,3-dicyanopyrazine, 5,6-diaminopyridin 2,4 —Dihydroxypyrimidine, 2,4-diamino —6-Dimethylamino-1,3,5-triazine, 1,4-bis (3-aminobutyral pill) piperazine, 2,4-diamino-6-isopropoxy-1,3 , 5-triazine, 2,4-diamino-6-methoxy-1,3,5-triazine, 2,4-diamino-6-phenyl_1,3,5_triazine, 2,4-diamino-6-methyl-s— Triazine, 2,4-diamino-1,3,5-triazine, 4,6-diamino-2-pinyl-s-triazine, 2,4-diamino-5-phenylthiazole, 2,6-diaminopurine, 5,6-diamino_1, 3—dimethylperacyl, 3, 5— Amino-1,2,4-triazole, 6,9-diamino-2-ethoxyethoxylidine lactate, 3,8-diamino-6-phenylphenanthridine, 1,4-diaminopyrazine, 3 Diamines having two primary amino groups and a nitrogen atom other than the primary amino groups in the molecule, such as 1,6-diaminoacridine and bis (4-aminophenyl) phenylamine;

And diaminoorganosiloxane represented by the following formula (IV). These diamines can be used alone or in combination of two or more.

In the formula, R ⁷ represents a hydrocarbon group having 1 to 12 carbon atoms, a plurality of R ⁷ may be the same or different, p is an integer of 1 to 3, and q is 1 to It is an integer of 20.

Of these, p-phenylenediamine, 4,4, -diaminodiphenylmethane, 4,4, diaminodiphenyl sulfide, 2,2'-dimethyl-4,4, -diaminobiphenyl, 1,5-diamino Naphthalene, 2,7-diaminofluorene, 4,4, -diaminodiphenyl ether, 2,2-bis [4- (4-aminodiphenyl Nonoxy) phenyl] propane, 9,9_bis (4-aminophenyl) fluorene, 2,2-bis [4- (4-aminophenyl) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) Hexafluoropropane, 4,4,1- (p-phenylenedisoisopropylidene) bisaniline, 4,4,1- (m-phenylenediisopropylidene) bisaniline, 1,4-cyclohexanediamine, 4, 4,1-methylenebis (cyclohexylamine), 1,4-bis (4-aminophenoxy) benzene, 4,4,1-bis (4-aminophenoxy) biphenyl, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4 Diaminopyrimidine, 3,6-diaminoacridine and the like are preferred.

(B) imidized polymer

<Tetra-potassium dianhydride>

The tetracarboxylic dianhydride used in the synthesis of the imidized polymer of the component (B) is the same as the tetracarboxylic dianhydride used in the synthesis of the polyamic acid of the component (A) described above. Can be mentioned.

Of these, alicyclic tetracarboxylic dianhydrides are preferred, and specifically, 1,2,3,4-cyclobutanetetracarponic dianhydride, 1,3-dimethyl-1,2,3,4 -Ciglobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic acid Dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 5- (2,5-dioxotetrahydrofural) 1,3-methyl-3-cyclohexene-1,2-dicarboxylic dianhydride Cis-3,7-dibutylcyclooctanol 1,5-diene 1,2,5,6-tetracarponic dianhydride, 3,5,6-tripropanol 2--2-propoxynorpornan 1 2: 3,5: 6-dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahedral Hydro-2,5-dioxo-1-3-furanyl) 1-naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-Hexahydro-8-methyl-5- (Tetrahydro-2,5-dioxo-3-furanyl) 1-naphtho [1,2-c] furan 1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5,8- Dimethyl-5- (tetrahydro-2,5-dioxo-1-furanyl) 1-naphtho [1,2-c] furan-1,3-dione, bicyclo [2,2,2] —oct-7—ene-1 2,3 , 5,6-tetracarboxylic dianhydride, 3-oxabicyclo [3,2,1] octane-1,2,4-dione-6-spiro-1,3,1- (tetrahydrofuran-1,2 ', 5'-dione), the above formula Among the compounds represented by (Π), the above formulas (5) to

Of the compound represented by the formula (7) and the compound represented by the formula (m),

The compound represented by (8) is preferable from the viewpoint of exhibiting good liquid crystal alignment and electrical properties, and particularly preferable are 1,2,3,4-cyclobutanetetracarboxylic dianhydride and 1 To 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tripropoxycyclopentyl acetic dianhydride, 1,3,3a, 4,5,9b— Xahydro-5- (tetrahydro 2,5-dioxo-3-furanyl) naphtho [1,2-c] furan-1,3-dione 1,3,3a, 4,5,9b-hexahydro-8 —Methyl— 5 _ (tetrahydro-1,2,5-dioxo-13-furanyl) naphtho [1,2, c] furan-1,3-dione, cis-1,3,7-dibutylcycloocta-1, 5-Gen _ 1,2,5,6-tetracarboxylic dianhydride, 3,5,6-tripropionyl-2-ppoloxy Polnan-1: 3,5: 6-dianhydride, 3-oxabicyclo [3,2,1] octane-1,2,4-dione-6-spiro-1,3,1- (tetrahydrofuran-1,2,5, -dione) and above The compound represented by the formula (1) is exemplified. These tetracarboxylic dianhydrides are used alone or in combination of two or more.

From the viewpoint of the electrical properties of the obtained liquid crystal alignment film, these tetracarboxylic dianhydrides are such that the alicyclic tetracarboxylic dianhydride is

It is preferable to use 50 mol% or more. That is, in the above formula (1-2), the repeating unit in which the tetravalent organic group represented by P ² is a group having an alicyclic structure accounts for 50 mol% of all the repeating units in the component (B). It is preferable that it is above.

Preferred tetracarboxylic dianhydrides other than the alicyclic tetracarboxylic dianhydride (preferably used in combination with the alicyclic tetracarboxylic dianhydride) include: Aromatic tetracarboxylic dianhydrides having a steroid skeleton represented by the above formulas (1) to (4) can be mentioned.

The specific diamine used for the synthesis of the imidized polymer of the component (B) is a diamine having a group represented by the above formula (Q-1) and the above formula (Q-2). These are used alone or in combination of two or more.

In the above formula (Q-1), examples of the alkyl group having 10 to 20 carbon atoms represented by R ¹ include n-decyl group, n-dodecyl group, n-pentadecyl group, and n- Examples include a xadecyl group, an n_octadecyl group, and an n-eicosyl group. Examples of the organic group having an alicyclic skeleton having 4 to 40 carbon atoms represented by R ^{1 in the} above formula (Q-1) and R ² in the above formula (Q-2) include cyclobutane and cyclo Groups having an alicyclic skeleton derived from cycloalken such as pentane, cyclohexane and cyclodecane; groups having a steroid skeleton such as cholesterol and cholesterol; groups having a bridged alicyclic skeleton such as norpolpolene and adamantane. And the like. Among these, a group having a steroid skeleton is particularly preferred. The organic group having the alicyclic skeleton may be a group substituted with a halogen atom, preferably a fluorine atom, or a fluoroalkyl group, preferably a trifluoromethyl group.

Examples of the group having a fluorine atom having 6 to 20 carbon atoms represented by R ¹ in the above formula (Q-1) include, for example, n-hexyl group, n-octyl group, n-decyl group and the like. Linear alkyl group having 6 or more carbon atoms; alicyclic hydrocarbon group having 6 or more carbon atoms such as cyclohexyl group and cyclooctyl group; and aromatic hydrocarbon having 6 or more carbon atoms such as phenyl group and biphenyl group. Examples thereof include groups in which part or all of the hydrogen atoms in an organic group such as a hydrogen group are substituted with a fluorine atom or a fluoroalkyl group such as a trifluoromethyl group.

Further, X ¹ in the above formula (Q-1) and X ² and X ³ in the above formula (Q-2) are each independently a single bond, 110-1, —CO—, —CO —,- OC is one, one NHCO—, one CONH—, one S— or arylene group. Early Examples of the len group include a phenylene group, a tolylene group, a biphenylene group, and a naphthylene group. Of these, a group represented by one O—, one COO—, —OCO— is particularly preferred.

Specific examples of the diamine having a group represented by the above formula (Q-1) include dodecanoloxy 2,4 diaminobenzene, pendecanoxy-1,2,4 diaminobenzene, hexadecanoxy 1,2,4 —Diaminobenzene, octadecanoloxy-1,4 diaminobenzene, and compounds represented by the following formulas (9) to (14) are preferred.

Further, as specific examples of the diamine having a group represented by the above formula (Q-2), diamines represented by the following formulas (15) to (17) can be preferably mentioned.

Among these, particularly preferred are the compounds represented by the above formulas (9), (10), (13), (14) and (15).

The proportion of the specific diamine used in the synthesis of the component (B) is preferably at least 5 mol%, more preferably at least 10 mol%, based on the total diamine used for the synthesis of the component (B). When the use ratio of the specific diamine is less than 5 mol%, a sufficient effect on the vertical orientation may not be obtained. That is, of all the repeating units having an imide ring, the proportion of the repeating unit represented by the above formula (1-2) is preferably at least 5 mol%, particularly preferably at least 10 mol%.

Other diamines that can be used in combination with the specific diamine include the aforementioned (A) component. And the same diamines used for the synthesis of the polyamic acid.

Of these, P-phenylenediamine, 4,4, diaminodiphenylmethane, 4,4, diaminodiphenyl sulfide, 2,2'-dimethyl-4,4, diaminobiphenyl, 1,5 diamino Naphthalene, 2,7-diaminofluorene, 4,4, -diaminodiphenylether, 2,2-bis [4- (4-aminophenyl) phenyl] propane, 9,9-bis (4-aminophenyl) Fluorene, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 4,4 '— ( 1-phenylenedisopropylidene) bisaniline, 4,4,1- (m-phenylenediisopropylidene) bisaniline, 1,4-cyclohexanediamine, 4,4'-methylenebis (cyclohexylamine), 1,4-1 Bi (4-aminophenoxy) benzene, 4,4,1-bis (4-aminophenoxy) biphenyl, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminoacridine, Preferred are diaminoorganosiloxanes represented by the above formula (IV). These are used alone or in combination of two or more.

Synthesis of polyamic acid

The ratio of tetracarboxylic dianhydride and diamine used in the synthesis reaction of the polyamic acid (precursor of component (A) and component (B)) is as follows: 1 equivalent of amino group of diamine and tetracarboxylic acid The ratio is preferably such that the acid anhydride group of the dianhydride becomes 0.2 to 2 equivalents, and more preferably the ratio becomes 0.3 to 1.2 equivalents.

The synthesis reaction of the polyamic acid is carried out in an organic solvent, preferably at a temperature of from 120 ° C to 150 ^, more preferably from 0 to 10 ° C.

Here, the organic solvent is not particularly limited as long as it can dissolve the synthesized polyamic acid. For example, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethylsulfoxide Non-protocols such as carboxylolactone, tetramethylurea, hexamethylphosphortriamide Polar solvents; phenolic solvents such as m-cresol, xylenol, phenol, and halogenated phenol. In addition, the amount of the organic solvent used (h) is such that the total amount of the tetracarboxylic dianhydride and the diamine compound (3) is 0.1 to 30% by weight based on the total amount of the reaction solution (h + 3). It is preferred that the amount be such.

As the organic solvent, alcohols, ketones, esters, ethers, halogenated hydrocarbons, hydrocarbons, etc., which are poor solvents for the polyamic acid, are used in combination as long as the generated polyamic acid does not precipitate. be able to. Specific examples of such poor solvents include, for example, methyl alcohol, ethyl alcohol, isopropyl alcohol, cyclohexanol, 4-hydroxy-14-methyl-21-pentanone (diacetone alcohol), ethylene glycol, propylene glycol, , 4-butanediol, triethylene glycol, ethylene glycol monomethyl ether, ethyl lactate, butyl lactate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl acetate, ethyl acetate, butyl acetate, methyl methoxypropionate , Ethyl ethoxy propionate, getyl oxalate, getyl malonate, getyl 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 teracetate, diethylene glycol dimethyl ether, diethylene glycol monoethyl ether, diethylene dalicol monomethyl ether, diethylene glycol Monoethyl ether, Dethylene glycol monomethyl ether acetate, Diethylene glycol monoethyl ether acetate, Tetrahydrofuran, Dichloromethane, 1,2 Dichloroethane, 1,4 Dichlorobutane, Trichloroethane, Chlorobenzene, Polydichlorobenzene, To Examples include xane, heptane, octane, benzene, toluene, and xylene. Kill.

As described above, a reaction solution obtained by dissolving the polyamic acid is obtained. The reaction solution is poured into a large amount of a poor solvent to obtain a precipitate, and the precipitate is dried under reduced pressure. By drying, a polyamic acid can be obtained. In addition, the polyamic acid can be purified by dissolving the polyamic acid in an organic solvent again and then performing the step of precipitating with a poor solvent once or several times.

Synthesis of imidized polymer (component (B))

The component (B) can be synthesized by subjecting part or all of the above polyamic acid to dehydration and ring closure. The component (B) used in the present invention preferably has a proportion of the repeating unit having an imide ring in all the repeating units (hereinafter, also referred to as “imidation ratio”), more preferably 40 mol% or more, more preferably. 70 mol% or more. By using a polymer having an imidation ratio of 40 mol% or more, a liquid crystal aligning agent capable of forming a liquid crystal alignment film having a short afterimage erasing time can be advantageously obtained.

The dehydration and ring closure of the polyamic acid can be performed by (i) heating the polyamic acid or (ii) dissolving the polyamic acid in an organic solvent, adding a dehydrating agent and a dehydration ring-closing catalyst to the solution, and heating as necessary. It is done by the method of doing.

The reaction temperature in the method of heating the polyamic acid of (i) is preferably 50 to 200 ° C, more preferably 60 to 170 ° C. When the reaction temperature is lower than 50 ° C, the dehydration ring-closing reaction does not easily proceed sufficiently. When the reaction temperature exceeds 200 ° C, the molecular weight of the imidized polymer obtained may decrease.

On the other hand, in the above method (ii) of adding a dehydrating agent and a dehydration ring-closing catalyst to the polyamic acid solution, as the dehydrating agent, for example, an acid anhydride such as acetic anhydride, propionic anhydride, and anhydrous trifluoroacetic acid is used. be able to. The amount of the dehydrating agent used depends on the desired imidation ratio, but is preferably 0.01 to 20 mol per 1 mol of the repeating unit of the polyamic acid. As the dehydration ring-closing catalyst, for example, tertiary amines such as pyridine, collidine, lutidine, and triethylamine can be used. However, it is not limited to these. The amount of the dehydration ring-closing catalyst used is preferably from 0.01 to 10 mol per 1 mol of the dehydrating agent used. The imidation ratio can be increased as the amount of the above-mentioned dehydrating agent and dehydrating ring-closing agent increases. Examples of the organic solvent used for the dehydration ring closure reaction include the same organic solvents as those exemplified above as those used for the synthesis of polyamic acid. And The reaction temperature of the water ring closure reaction is preferably from 0 to 180 ° C, more preferably from 10 to 150 ° C. The obtained imidized polymer can be purified by subjecting the reaction solution thus obtained to the same operation as in the method for purifying polyamic acid.

Terminally modified polymer

The components (A) and (B) used in the present invention may be of a terminal-modified type having a controlled molecular weight. By using this terminal-modified polymer, the coating characteristics of the liquid crystal aligning agent can be improved without impairing the effects of the present invention. Such a terminal-modified polymer can be synthesized by adding an acid monohydrate, a monoamine compound, a monoisocyanate compound, or the like to the reaction system when synthesizing the polyamic acid. Here, examples of the acid monoanhydride include maleic anhydride, phthalic anhydride, itaconic anhydride, n-decylsuccinic anhydride, n-dodecylsuccinic anhydride, and n-tetradecylsuccinic anhydride. And n-hexadecyl succinic anhydride. Monoamine compounds include, for example, aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-noeramine, n-decylamine, n-Pindecylamine, n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-hepdecylamine, n-octadecylamine, n-eicosylamine and the like. Further, examples of the monodisocyanate compound include phenyl isocyanate and naphthyl isocyanate.

Logarithmic viscosity of polymer

The polymer used in the present invention has a logarithmic viscosity (77 _ln ) value of preferably from 0.05 to: L 0 d 1 / g, more preferably from 0.05 to 5 dl / g.

The value of the logarithmic viscosity (77 _ln ) in the present invention is determined by measuring the viscosity at 30 ° C. of a solution having a concentration of 0.5 g / 100 ml using N-methyl-2-pyrrolidone as a solvent. And it is obtained by the following equation (i). 1 n (solution flowing time Z solvent flowing time)

l _n = (1)

(Polymer concentration by weight) Block copolymer

When the block copolymer shown in (1) above is used as the polymer used in the present invention, an acid anhydride group having an amino group or an acid anhydride group at the terminal and an acid anhydride group or a acid terminal at the terminal are used. A block copolymer can be produced by synthesizing an imidoble polymer having an amino group, respectively, and binding the terminal amino group and acid anhydride group of each prepolymer. The method for synthesizing the preamic polymer is the same as the above-described method for synthesizing the polyamic acid, and the method for synthesizing the imidoblepolymer is the same as the method for synthesizing the imidized polymer described above. The selection of the functional group at the terminal can be made by adjusting the amounts of tetracarboxylic dianhydride and diamine during the synthesis of the polyamic acid.

Liquid crystal alignment agent

The liquid crystal aligning agent of the present invention is constituted as a solution in which the above-mentioned polymer component, preferably the component (A) and the component (B), are usually dissolved in an organic solvent. The mixing ratio of the polyamic acid as the component (A) and the imidized polymer as the component (B) is preferably 99.9 / 0.01-10 / 90, and particularly preferably 99.9 / 0/10. 1 to 40/60.

The temperature for preparing the liquid crystal aligning agent of the present invention is preferably from 0 ^{nC to} 200 ° C, more preferably from 20 ° C to 60 ° C.

Examples of the organic solvent constituting the liquid crystal aligning agent of the present invention include N-methyl-2-pyrrolidone, a-butyrolactone, a-butyrolactam, N, N-dimethylformamide, N, N-dimethylacetamide, 4-hydroxy-4 -Methyl-2-nonene, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol n-propyl ether , Ethylene glycol i-propyl ether, ethyl N-Butyl ether (ethylene glycol dimethyl ether), ethylene glycol dimethyl ether acetate, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol dimethyl ether, and ethylene glycol monomethyl ether And ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, and diethylene glycol monoethyl ether acetate.

The solid content concentration in the liquid crystal aligning agent of the present invention is selected in consideration of viscosity, volatility, and the like, but is preferably in the range of 1 to 10% by weight. The liquid crystal aligning agent of the present invention is applied to a substrate surface to form a coating film to be a liquid crystal alignment film. When the solid content is less than 1% by weight, the thickness of the coating film is too small. It is difficult to obtain a good liquid crystal alignment film because the solid content concentration exceeds 10% by weight. It becomes difficult, and the viscosity of the liquid crystal aligning agent increases, thereby deteriorating the coating properties.

The liquid crystal aligning agent of the present invention may contain a functional silane-containing compound or an epoxy compound from the viewpoint of improving the adhesiveness to the substrate surface as long as the desired physical properties are not impaired. Such functional silane-containing compounds include, for example, 3-amino

Mouth pilltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl 1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9- Trimethoxysilyl-1,3-diazanyonylacetate, 9-triethoxysilyl-1,3,6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N— Propyltrimethoxysilane, N-phenyl 3-aminopropyltriethoxysilane, N-bis (oxyethylene) -13-aminopropyltrimethoxysilane, N-bis (oxyethylene) -13-aminopropyltriethoxysilane And so on.

Examples of such epoxy compounds include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol didalidicyl ether, tripropylene dalicol diglycidyl ether, polypropylene dalicol diglycidyl ether, and neopentyl glycol diglycidyl. Ether, 1,6-hexanediol diglycidyl ether, glycerin didaricidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl 2,4-hexanediol, N, N, N,, Ν,, —tetraglycidyl-1-m-xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N,, N ′, —Tetraglycidyl— 4, 4, 4, Jiaminojifue two Rume Yun, 3- (N- Ariru one N- glycidyl) § amino propyl trimethoxy silane, 3 - (N, N- diglycidyl) and the like § amino propyl trimethoxy silane.

The mixing ratio of these functional silane-containing compounds and epoxy 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 polymer. In particular, the addition of an epoxy compound can further improve the scratch resistance of the obtained liquid crystal alignment film. Particularly preferred epoxy compounds are N, N, N,, Ν,, —tetraglycidyl m-xylene diamine, 1,3-bis

(N, N-diglycidylaminomethyl) cyclohexane, N, N, Ν,, N,, —tetraglycidyl—4,4 ′ diaminodiphenylmethane, 3 -— (N-aryl-1N-glycidyl) N-containing epoxy compounds such as aminopropyl trimethoxysilane and 3- (N, N-diglycidyl) aminopropyltrimethoxysilane.

In the liquid crystal alignment agent of the present invention, at least one substrate forming a liquid crystal cell has a projection shape. Can be suitably used for a vertical alignment type liquid crystal display device having Examples of the liquid crystal display element include an MVA type liquid crystal display element. The MVA mode is a vertical alignment mode in which projections are used as alignment control means, as shown in "Liquid Crystal Vol. 3 No. 2117 (1999)", JP-A-11-258605. The projection may be formed on each of the TFT substrate side and the color filter side, and may have a projection on the color filter side and a slit on the TFT side. Example

Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

Method for measuring imidization rate

After drying the polymer under reduced pressure at room temperature, it was dissolved in deuterated dimethyl sulfoxide, ¹ H-NMR was measured at room temperature using tetramethylsilane as a reference substance, and the value was determined by the following formula (ii).

Imidation rate (%) = (1 -Α ^Χ / Α ² Χα) X 100 (ii)

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

A ² : Peak area derived from other protons

: Number ratio of other protons to one proton of NH group in polymer precursor (polyamic acid)

Method for manufacturing liquid crystal display element

As shown in Fig. 1, a liquid crystal aligning agent was printed on the glass substrate with ITO (A) and the glass substrate with ITO pattern (B) having protrusions formed using a positive resist, respectively. The film was dried at 80 ° C for 1 minute and then at 180 ° C for 1 hour to produce a 600 Å film thickness.

Two substrates on which a liquid crystal alignment film was formed as described above were prepared, and an epoxy resin-based adhesive containing 3.5 m-diameter aluminum balls was applied to the outer edge of the substrate (B). After application by screen printing, the two substrates were bonded together in a positional relationship as shown in Figure 1. The liquid crystal MLC660 from Merck is injected and filled into the cell gap defined by the adhesive on the surface of the substrate and the outer edge, and then the injection hole is sealed with an epoxy-based adhesive to remove the vertically aligned liquid crystal. A display element was manufactured. In FIG. 1, 1 is a color filter side electrode (ITO), 2 is a liquid crystal alignment film, 3 is a pixel electrode (ITO), 4 is an alignment regulating means (projection), and 5 is an alignment regulating means (slit). , And 6 are liquid crystal molecules.

Vertical orientation

The liquid crystal display device was observed under crossed Nicols at the voltage OFF and at AC 12 V (peak to peak).

Voltage holding ratio

After a voltage of 5 V was applied to the liquid crystal display element with an application time of 60 msec and a span of 167 ms, the voltage holding ratio was measured 167 ms after the application was canceled. The measuring device used was VHR-1 manufactured by Toyo Corporation.

Afterimage elimination time of liquid crystal display

A 30 Hz, 3.0 V rectangular wave with 3.0 V DC and 6.0 V AC (peak-to-peak) superimposed on the liquid crystal display element is applied for 20 hours at an ambient temperature of 70 ° C. Then, the voltage was turned off, and the time until the afterimage disappeared was visually measured.

Synthesis Examples 1 to 9

N-Methyl-2-pyrrolidone was added in the order shown in Table 1 in the order of diamine and tetracarboxylic dianhydride. Synthesis Examples 3, 4, 6, 8, and 9 were 30 weight percent solids. %, At 60 ° C for 6 hours. Synthesis Examples 1, 2, 5, 7, and 10 were reacted at room temperature for 20 hours at a solid content of 20% by weight and reacted at room temperature for 6 hours. Citrate I ~; table 1

Number in 0 is mol%

T C AAH: 2, 3, 5-tricarpoxycyclopentyl acetic acid dianhydride

CB: 1,2,3,4-cyclobutanetetracarboxylic dianhydride

PMDA: pyromellitic dianhydride

PDA: p-Fenylenediamine

DDE: 4, 4, diamino diphenyl ether

DDM: 4, 4

MTB: 2,2'-dimethyl-4,4'-diaminobiphenyl

Diamine: diamine represented by formula (9)

Diamine: diamine represented by formula (10)

Diamine ③: diamine represented by formula (13)

Diamine II: bisaminopropyltetramethyldisiloxane

Synthesis Example 1 1-18

Each of the polyamic acids shown in Table 2 was diluted to a solid concentration of 5% by weight with N-methyl-2-pyrrolidone, and the amount of pyridine added was as shown in Table 2 for each mole of diamine used in the synthesis of each polyamic acid. And acetic anhydride at 110 ° C for 4 hours By stirring for a while, imidized polymers ① to ⑧ were synthesized. The polymer solution was reprecipitated with dimethyl ether to obtain a white powder of an imidized polymer. The imidation ratio of the obtained polymer is also shown in Table 2. Table 2

Examples 1 to 14, Comparative Examples 1 to 3

Polyamic acid (component (A)), imidized polymer (component (B)) obtained in Synthesis Examples 1-18, and N, N, Ν ', Ν'-tetraglycidyl- 4,4'-Diaminodiphenylmethane (epoxy compound) was mixed with a composition as shown in Table 3 and adjusted to a solid concentration of 6.0% by weight to obtain a vertical alignment type liquid crystal alignment agent of the present invention. . Using this liquid crystal aligning agent, a liquid crystal display device was manufactured and various evaluations were made. Table 4 shows the results.

Table 3

* Figures in parentheses are as follows.

Component (A) · Component (B):% by weight based on the whole polymer

Solvent:% by weight of each solvent type based on the total solvent

* The amount of additives is parts by weight of additives with respect to 100 parts by weight of polymer.

* Abbreviations of solvent types are as follows.

BL: γ-butyrolactone

ΝΜΡ: Ν-methyl-2-pyrrolidone

BC: Solvent mouth

DAA: 4-Hydroxy-4-methyl-2-pennone (diacetone alcohol) Table 4

ADVANTAGE OF THE INVENTION According to the liquid crystal aligning agent of this invention, the vertical alignment of a liquid crystal is favorable and the afterimage elimination time is short, and a liquid crystal alignment film suitable for an MVA-type liquid crystal display element can be obtained.

Claims

The scope of the claims

1. (A) a polymer having a repeating unit represented by the following formula (1-1) and (B) a repeating unit represented by the following formula (1-2): Liquid crystal vertical alignment liquid crystal alignment agent.

[Formula 1]

(1)

Wherein, [rho ¹ is a tetravalent organic group, Q ¹ represents a divalent organic group _c

[Formula 2]

In the formula, P ² is a tetravalent organic group, and Q ² is a divalent group represented by the following formula (Q-1) or the following formula (· 2).

Wherein X ¹ is a single bond, —〇—, —CO—, one C〇〇, one OCO—, —NHC 0—, — CONH—, —S— or arylene group, and R ¹ is an alkyl group having 10 to 20 carbon atoms, a monovalent organic group having an alicyclic skeleton having 4 to 40 carbon atoms, or a monovalent organic group having a fluorine atom having 6 to 20 carbon atoms.

In the formula, X ² and X ³ are the same or different and are a single bond, —O—, one C〇, -C〇0_, one OCO—, one NHC0—, one CONH—, one S— or an arylene group. R ² is a divalent organic group having an alicyclic skeleton having 4 to 40 carbon atoms.

2. The liquid crystal aligning agent according to claim 1, wherein the polymer contains 5 mol% or more of the repeating unit represented by the above formula (1-2) in all the repeating units having an imide ring.

3. The liquid crystal aligning agent according to claim 1, wherein the vertical alignment type liquid crystal display device using the same has a projection on at least one substrate forming a liquid crystal cell.