KR20060047211A - Vertical alignment-type liquid crystal aligning agent and liquid crystal display device - Google Patents

Abstract

This invention provides the liquid crystal aligning agent provided with the vertical orientation of a liquid crystal, high voltage retention, and favorable applicability | paintability to a board | substrate.

The imidation which the imid repeating unit occupies 60 mol% or more with respect to the sum total of these repeating units, including the amic acid repeating unit and imide repeating unit obtained using the specific diamine component It contains a polymer.

Vertical alignment property, a liquid crystal aligning agent, a liquid crystal display element, voltage retention, applicability | paintability, a repeating unit, an imidation polymer, a diamine component

Description

Vertical alignment liquid crystal aligning agent and liquid crystal display device {Vertical Alignment-Type Liquid Crystal Aligning Agent and Liquid Crystal Display Device}

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram of the MVA type vertically-aligned liquid crystal display element used for the Example of this invention.

2 is a schematic view of a vertical alignment type liquid crystal display device of the EVA method used in the embodiment of the present invention.

<Brief description of symbols for the main parts of the drawings>

1 Color filter side electrode (ITO)

2 liquid crystal aligning film

3 pixel electrode (ITO)

4 orientation control means (projection)

5 orientation control means (slits)

6 liquid crystal molecules

The present invention relates to a vertical alignment liquid crystal aligning agent and a liquid crystal display element. More specifically, the present invention relates to a vertically aligned liquid crystal aligning agent and a liquid crystal display device having good vertical alignment, good coating properties, and high voltage retention.

In view of space saving and low power consumption, liquid crystal display devices represented by liquid crystal displays have been used in various fields, and active development has been made. As a conventional display method, a liquid crystal having a positive dielectric anisotropy is used, and a TN method or an STN method which drives liquid crystal molecules from a parallel to a vertical direction with respect to a substrate surface by voltage application has been widely used.

Recently, in addition to the TN method or the STN method for further improving the display quality, a VA method has been developed in which a liquid crystal having a dielectric anisotropy is used and liquid crystal molecules are arranged in parallel to the substrate surface at the time of voltage application. . In the VA method, since black display is performed when no voltage is applied, the amount of light transmitted can be easily reduced as compared with the TN method or the STN method, and a high contrast contrast can be obtained without increasing the backlight brightness. .

A liquid crystal aligning film originally aims at orienting liquid crystal molecules in the uniaxial direction, but it is desired to have electrical characteristics with high voltage retention and low residual charge for the purpose of obtaining a higher quality display as an actual element. Moreover, as an important characteristic requested | required of the liquid crystal aligning film in VA system, the initial stage orientation state at the time of voltageless application of a liquid crystal molecule is mentioned. In the conventional TN method or STN method, the inclination angle of the liquid crystal with respect to the substrate surface when no voltage is applied is about several degrees, while the VA method requires an orientation treatment such as a rubbing treatment. To regulate the angle in the vertical vicinity. Moreover, in this case, it is characterized by not requiring a rubbing process.

Conventionally, since these liquid crystal aligning films are excellent in heat resistance, affinity with a liquid crystal, or mechanical strength, polyamic acid or the polyimide which carried out the dehydration ring closure of this in many display modes is used for many liquid crystal display elements.

Currently, the liquid crystal aligning film of a vertical alignment liquid crystal display element is formed by apply | coating a liquid crystal aligning agent to a board | substrate, as described in Unexamined-Japanese-Patent No. 2002-327058, and (1) vertical alignment property of a liquid crystal is needed as a basic characteristic. . Recently, in addition to the vertical alignment, (2) high voltage retention and (3) good applicability to a substrate are required. For example, when the voltage retention is low, luminance unevenness occurs when impurities are mixed into the liquid crystal from the outside. It becomes easy to do it. Moreover, when applicability | paintability to a board | substrate of a liquid crystal aligning agent is bad, film thickness unevenness and a pinhole generate | occur | produce, for example in an orientation film, and it causes a display defect and brightness unevenness.

An object of the present invention is to provide a liquid crystal aligning agent which has all of the vertical alignment property of a liquid crystal, high voltage retention, and favorable coating property on a board | substrate.

Another object of this invention is to provide the liquid crystal display element provided with the liquid crystal aligning film by the said liquid crystal aligning agent of this invention.

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

According to the present invention, the above objects and advantages of the present invention include, firstly, an amic acid repeating unit represented by the following general formula (1a) and an imide repeating unit represented by the following general formula (1b). It is achieved by the vertically-aligned liquid crystal aligning agent, characterized in that the de-repeat unit contains an imidized polymer occupying 60 mol% or more.

In formula, P <^1> is a tetravalent organic group, Q <^1> is at least 1 sort (s) of bivalent organic groups represented by following formula (2a) or (2b), and 1 sort (s) of divalent organic group represented by following formula (2c) or 2d, respectively. It includes a combination with the above.

In formula, P <^2> is a tetravalent organic group, Q <^2> is at least 1 sort (s) of the bivalent organic group represented by following formula (2a) or (2b), and at least 1 sort (s) of bivalent organic group represented by formula (2c) or (2d), respectively. And combinations thereof.

Wherein X ¹ is a single bond, -O-, -CO-, -COO-, -OCO-, -NHCO-, -CONH-, -S- or an arylene group, R ¹ is an alkyl group having 10 to 20 carbon atoms , A monovalent organic group having 4 to 40 carbon atoms having an alicyclic skeleton, or a monovalent organic group having 6 to 20 carbon atoms having a fluorine atom.

Wherein, X ² represents a single bond, -O-, -CO-, -COO-, -OCO-, -NHCO-, -CONH-, -S- , or an arylene group, R ² is alkyl group which has an alicyclic skeleton It is a divalent organic group of 4-40.

Wherein X ³ is -O-, -CO-, -COO-, -OCO-, -NHCO-, -CONH-, -S- or an arylene group, R ³ is an alkylene group having 1 to 24 carbon atoms or halogenated Alkylene group.

In formula, R <^4> is a C1-C24 alkylene group or halogenated alkylene group.

According to this invention, the said objective and advantage of this invention are achieved by the liquid crystal display element characterized by providing the liquid crystal aligning film obtained from the vertically-aligned liquid crystal aligning agent of this invention secondly.

Best Mode for Carrying Out the Invention

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

The imidated polymer is melt | dissolved in the organic solvent, and the vertically-aligned liquid crystal aligning agent of this invention is comprised. The imidized polymer is obtained by dehydrating and closing the amic acid portion of the polyamic acid obtained by reacting tetracarboxylic dianhydride and diamine.

That is, the imidation polymer used by this invention contains the amic acid repeating unit represented by the said Formula (1a), and the imide repeating unit represented by the said Formula (1b). In the formulas (1a) and (1b), the tetravalent organic groups of P ¹ and P ² correspond to residues obtained by removing two acid anhydride groups from tetracarboxylic dianhydride.

Tetracarboxylic anhydride

As tetracarboxylic dianhydride used for the synthesis | combination of the said imidation polymer, the following specific tetracarboxylic dianhydride is preferable. As a specific example of specific tetracarboxylic dianhydride, it is 1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2-dimethyl-1,2,3,4-cyclobutane tetracarr, for example. Acid dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dichloro-1,2,3,4-cyclobutanetetracarboxylic dianhydride , 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2, 4,5-cyclohexanetetracarboxylic dianhydride, 3,3 ', 4,4'-dicyclohexyltetracarboxylic dianhydride, cis-3,7-dibutylcycloocta-1,5-diene- 1,2,5,6-tetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 3,5,6-tricarbonyl-2-carboxynorbornane-2: 3, 5: 6-di-anhydride, 2,3,4,5-tetrahydrofurantetracarboxylic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5 (tetra Dro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5- Methyl-5 (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b- Hexahydro-5-ethyl-5 (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4 , 5,9b-hexahydro-7-methyl-5 (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1, 3,3a, 4,5,9b-hexahydro-7-ethyl-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-2,5-dioxo-3-furanyl) -naphtho [1,2-c]- Furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-ethyl-5 (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1, 2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5,8-dimethyl-5 (tetrahydro-2,5-dioxo-3-fura Nil) -naphtho [1,2-c] -furan-1,3-dione, 5- (2,5-dioxotetrahydrofural) -3-methyl-3-cyclo Hexene-1,2-dicarboxylic dianhydride, bicyclo [2,2,2] -octo-7-ene-2,3,5,6-tetracarboxylic dianhydride, 3-oxabicyclo [ 3,2,1] octane-2,4-dione-6-spiro-3 '-(tetrahydrofuran-2', 5'-dione), compounds represented by the following formulas (3) and (4), and the like.

In formula, R <^5> and R <^8> represents the divalent organic group which has an aromatic ring, R <^6> and R <^7> represents a hydrogen atom or an alkyl group, and two or more R <^6> and R <^7> may be same or different, respectively.

In addition to said specific tetracarboxylic dianhydride, you may use together other tetracarboxylic dianhydride as long as it is a range which does not prevent the effect of this invention.

As another tetracarboxylic dianhydride, For example, Aliphatic tetracarboxylic dianhydride like a butane tetracarboxylic dianhydride;

Pyromellitic dianhydride, 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-biphenylsulfontetracarboxylic dianhydride, 1,4,5 , 8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3 ', 4,4'-biphenylethertetracarboxylic dianhydride, 3,3 ', 4,4'-dimethyldiphenylsilanetetracarboxylic dianhydride, 3,3', 4,4'-tetraphenylsilanetetracarboxylic dianhydride, 1,2,3,4-furantetracarboxylic Acid dianhydrides, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylsulfide dianhydrides, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylsulfone dianhydrides, 4 , 4'-bis (3,4-dicarboxyphenoxy) diphenylpropane dianhydride, 3,3 ', 4,4'-perfluoroisopropylidenediphthalic dianhydride, 3,3', 4,4 '-Biphenyltetracarboxylic dianhydride, bis (phthalic acid) phenylphosphineoxide dianhydride, p-phenylene-bis (triphenylphthalic acid) dianhydride, m-phenylene-bis (triphenylphthalic acid) dianhydride, bis (triphenylphthalic acid) -4,4'-diphenyl ether dianhydride, bis (triphenylphthalic acid) -4,4'-diphenylmethane dianhydride, Ethylene glycol bis (anhydrotrimelitate), propylene glycol bis (anhydro trimellitate), 1,4-butanediol-bis (anhydro trimellitate), 1,6-hexanediol-bis (anhydro Trimellitate), 1,8-octanediol-bis (anhydro trimellitate), 2,2-bis (4-hydroxyphenyl) propane-bis (anhydro trimellitate), the following formulas (1) to The aromatic tetracarboxylic dianhydride like the compound represented by (8) is mentioned. These are used individually by 1 type or in combination of 2 or more types.

1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride in the alicyclic tetracarboxylic dianhydride , 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 2,3, 5-tricarboxycyclopentylacetic dianhydride, 5- (2,5-dioxotetrahydrofural) -3-methyl-3-cyclohexene-1,2-dicarboxylic dianhydride, cis-3,7- Dibutylcycloocta-1,5-diene-1,2,5,6-tetracarboxylic dianhydride, 3,5,6-tricarbonyl-2-carboxynorbornane-2: 3,5: 6 Dianhydride, 1,3,3a, 4,5,9b-hexahydro-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-2,5-dioxo-3-furanyl) -naphtho [1,2- c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5,8-dimethyl-5- (tetrahydro-2,5-di Oxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, bicyclo [2,2,2] -octo-7-ene-2,3,5,6-tetra Carboxylic acid dianhydride, 3-oxabicyclo [3,2,1] octane-2,4-dione-6-spiro-3 '-(tetrahydrofuran-2', 5'-dione), Formula 3 It is preferable from the viewpoint that the compound represented by following formula (12) among the compound represented by following formula (9)-(11), and the compound represented by following formula (12) among the compound represented by the said formula can express favorable liquid-crystal orientation. . As particularly preferred, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5- Tricarboxycyclopentylacetic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c ] Furan-1,3-dione, cis-3,7-dibutylcycloocta-1,5-diene-1,2,5,6-tetracarboxylic dianhydride, 3,5,6-tricarbonyl 2-carboxynorbornane-2: 3,5: 6-dianhydride, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo -3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 3-oxabicyclo [3,2,1] octane-2,4-dione-6-spiro-3 ' -(Tetrahydrofuran-2 ', 5'-dione) and the compound represented by following General formula (12) are mentioned.

Among other tetracarboxylic dianhydrides, preferred are butanetetracarboxylic dianhydride, pyromellitic dianhydride, 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-biphenylsulfontetracarboxylic dianhydride and 1,4,5,8-naphthalenetetracarboxylic dianhydride.

It is preferable that alicyclic tetracarboxylic dianhydride is 50 mol% or more with respect to all tetracarboxylic dianhydride among these tetracarboxylic dianhydrides.

<Diamine>

The groups represented by the above formulas 2a, 2b, 2c and 2d each represented by Q ¹ and Q ² in the above formulas 1a and 1b are groups derived from diamines and correspond to residues obtained by removing two amino groups from diamines. Hereinafter, the diamine which has group represented by each of said General formula (2a) or (2b) may be called "specific diamine 1".

In Formula 2a, for example, an alkyl group having 10 to 20 carbon atoms represented by R ¹ is n-decyl group, n-dodecyl group, n-pentadecyl group, n-hexadecyl group, n-octadecyl group, n -An acyl group etc. are mentioned.

Moreover, as a C4-C40 monovalent organic group which has alicyclic skeleton, For example, Monovalent organic group which has alicyclic skeleton derived from cycloalkanes, such as cyclobutane, cyclopentane, cyclohexane, cyclodecane; Monovalent organic groups having a steroid skeleton such as cholesterol and cholestanol; And monovalent organic groups having a crosslinked alicyclic skeleton such as norbornene and adamantane. Among these, it is particularly preferably a monovalent organic group having a steroid skeleton. The monovalent organic group having the alicyclic skeleton may be a group substituted with a halogen atom, preferably a fluorine atom.

Moreover, as a C6-C20 monovalent organic group which has a fluorine atom represented by R <^1> , For example, C6-C20 linear alkyl groups, such as n-hexyl group, n-octyl group, n-decyl group; Alicyclic hydrocarbon groups having 6 to 20 carbon atoms such as a cyclohexyl group and a cyclooctyl group; The group which substituted a part or all of the hydrogen atoms in organic groups, such as a C6-C20 aromatic hydrocarbon group, such as a phenyl group and a biphenyl group, with the fluorine atom or the fluoroalkyl group, is mentioned.

In addition, the group represented by X ¹ in the formula (2a) is a single bond, -O-, -CO-, -COO-, -OCO-, -NHCO-, -CONH-, -S- or an arylene group, for example It is a phenylene group, Especially preferably, they are group represented by -0-, -COO-, -OCO-.

As a specific example of the diamine which has a group represented by the said General formula (2a), dodecanoxy-2, 4- diamino benzene, pentadecanoxy-2, 4- diamino benzene, hexadecanoxy-2, 4- dia Minobenzene, octadecanoxy-2,4-diaminobenzene, and the compound represented by following General formula (13)-(29) are mentioned as a preferable thing.

Moreover, as a C4-C40 divalent organic group which has an alicyclic skeleton represented by R <^2> in the said General formula (2b), For example, alicyclic skeleton derived from cycloalkane, such as cyclobutane, cyclopentane, cyclohexane, cyclodecane, etc. Divalent organic groups having; Divalent organic groups having a steroid skeleton such as cholesterol and cholestanol; And divalent organic groups having a crosslinked alicyclic skeleton such as norbornene and adamantane. Among them, particularly preferred are divalent organic groups having a steroid skeleton. The divalent organic group having the alicyclic skeleton may be a group substituted with a halogen atom, preferably a fluorine atom.

The group represented by X ² is a single bond, —O—, —CO—, —COO—, —OCO—, —NHCO—, —CONH—, —S— or an arylene group such as a phenylene group, among others Preferably it is group represented by -O-, -COO-, -OCO-. Two X ² may be the same or different.

Moreover, as a specific example of the diamine which has a group represented by the said General formula (2b), the diamine represented by following General formula (30)-(33) is mentioned as a preferable thing.

Next, the group represented by the said Formula (2c) and (2d) is demonstrated. Hereinafter, the diamine which has group represented by each of General formula (2c) or (2d) may be called "specific diamine 2".

As the alkylene group or halogenated alkylene group having 1 to 24 carbon atoms represented by R ³ in the formula (2c), for example, a straight chain such as a group represented by-(CH ₂ ) _p- (where p is an integer of 1 to 24) Branched alkylene groups such as alkylene groups, 2,2-propylene groups, or groups in which the hydrogen atoms of these groups are substituted with halogen atoms. As a halogen atom, a fluorine atom is preferable. The group represented by X ³ is a single bond, -O-, -CO-, -COO-, -OCO-, -NHCO-, -CONH-, -S- or an arylene group, among which -O-, -COO- , -OCO- is preferred. Two X ³ may be the same or different.

Moreover, as an alkylene group or halogenated alkylene group of 1 to 24 carbon atoms represented by R ⁴ in the formula (2d), the same groups as those for R ³ in the formula (2c) can be exemplified.

Among the diamines represented by the formula (2c), particularly preferred compounds include the compounds represented by the following formulas (34) and (35). Also preferred among the diamines represented by the formula (2d) are 4,4'-diaminodiphenylmethane, 4,4'-diamino-1,2-diphenylethane, 4,4'-diamino-1,3 -Diphenyl propane and the compound represented by following General formula (36), (37), etc. are mentioned.

In the formula (35), n is preferably an integer of 1 to 12, more preferably n is an integer of 2 to 6.

In the synthesis | combination of the polyamic acid used by this invention, another diamine compound can be used together to the extent which does not impair the effect of this invention. As another diamine compound, p-phenylenediamine, m-phenylenediamine, 4,4'- diamino diphenyl sulfide, 4,4'- diamino diphenyl sulfone, 3,3'- dimethyl, for example -4,4'-diaminobiphenyl, 4,4'-diaminobenzanilide, 4,4'-diaminodiphenylether, 1,5-diaminonaphthalene, 3,3-dimethyl-4,4 ' -Diaminobiphenyl, 5-amino-1- (4'-aminophenyl) -1,3,3-trimethylindane, 6-amino-1- (4'-aminophenyl) -1,3,3-trimethyl Indan, 3,4'-diaminodiphenylether, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, 4,4'-diaminobenzophenone, 2,2-bis [4 -(4-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] 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-aminophenyl) -10-hydroanthracene, 2,7-diaminofluorene, 9,9-bis (4- Minophenyl) fluorene, 4,4'-methylene-bis (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-phenyleneiso Propylidene) bisaniline, 4,4 '-(m-phenyleneisopropylidene) bisaniline, 2,2'-bis [4- (4-amino-2-trifluoromethylphenoxy) phenyl] hexafluoro Lopropane, 4,4'-diamino-2,2'-bis (trifluoromethyl) biphenyl, 4,4'-bis [(4-amino-2-trifluoromethyl) phenoxy] -octa Aromatic diamines such as fluorobiphenyl;

1,1-methacrylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, 4,4-diaminoheptamethylenediamine , 1,4-diaminocyclohexane, isophoronediamine, tetrahydrodicyclopentadienylenediamine, hexahydro-4,7-methanoindenylenedimethylenediamine, tricyclo [6.2.1.0 ^2,7 ] -undecylene Aliphatic and alicyclic diamines such as dimethyldiamine and 4,4'-methylenebis (cyclohexylamine);

2,3-diaminopyridine, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 5,6-diamino-2,3-dicyanopyrazine, 5, 6-diamino-2,4-dihydroxypyrimidine, 2,4-diamino-6-dimethylamino-1,3,5-triazine, 1,4-bis (3-aminopropyl) 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-dia Mino-2-vinyl-s-triazine, 2,4-diamino-5-phenylthiazole, 2,6-diaminopurine, 5,6-diamino-1,3-dimethyluracil, 3,5- Diamino-1,2,4-triazole, 6,9-diamino-2-ethoxyacridine lactate, 3,8-diamino-6-phenylphenanthtridine, 1,4-diaminopiperazine, Two primary amino groups in a molecule | numerator, such as 3, 6- diamino acridine and bis (4-aminophenyl) phenylamine, other than the said primary amino group Diamines having a nitrogen atom;

Diamino organosiloxane etc. which are represented by following formula (5) are mentioned.

In formula, R <^7> represents a C1-C12 hydrocarbon group, two or more R <^7> may be same or different, p is an integer of 1-3 and q is an integer of 1-20.

These diamine compounds can be used individually or in combination of 2 or more types.

Among them, p-phenylenediamine, 4,4'-diaminodiphenyl sulfide, 1,5-diaminonaphthalene, 2,7-diaminofluorene, 4,4'-diaminodiphenyl ether, 2 , 2-bis [4- (4-aminophenoxy) phenyl] propane, 9,9-bis (4-aminophenyl) fluorene, 2,2-bis [4- (4-aminophenoxy) phenyl] hexa Fluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 4,4 '-(p-phenylenediisopropylidene) bisaniline, 4,4'-(m-phenylenediisopropylidene ) Bisaniline, 1,4-cyclohexanediamine, 4,4'-methylenebis (cyclohexylamine), 1,4-bis (4-aminophenoxy) benzene, 4,4'-bis (4-aminophenoxy C) biphenyl, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminoacridine and the like are preferred.

The imidation polymer in this invention contains the amide acid repeating unit represented by the said Formula (1a), and the imide repeating unit represented by the said Formula (1b), and each unit is 40 mol% or less with respect to the sum total of all, Preferably Preferably at most 25 mol%, and at least 60 mol%, preferably at least 75 mol%. Especially preferably, it contains 10-25 mol% of amic acid repeat units and 75-90 mol% of imide repeat units.

The ratio of the divalent organic group derived from the specific diamine 1 in the imidation polymer contained in the liquid crystal aligning agent of this invention becomes like this. Preferably it is 7 mol% or more with respect to the diamine component total amount, More preferably, it is 10 mol% or more. to be. When this use ratio is less than 7 mol%, the effect sufficient for vertical alignment may not be acquired in some cases.

The ratio of the divalent organic group derived from the specific diamine 2 in the imidation polymer contained in the liquid crystal aligning agent of this invention becomes like this. Preferably it is 10 mol% or more with respect to the diamine component total amount, More preferably, it is 20 mol% or more. to be. When this use ratio is less than 10 mol%, favorable applicability may not be obtained.

<Synthesis of imidized polymer>

The imidized polymer is obtained by dehydrating and closing the amic acid portion of polyamic acid as a precursor.

[Synthesis of polyamic acid as an imidized polymer precursor]

The use ratio of the tetracarboxylic dianhydride and the diamine used in the synthesis reaction of the polyamic acid is preferably a ratio in which the acid anhydride group of the tetracarboxylic dianhydride is 0.2 to 2 equivalents to 1 equivalent of the amino group of the diamine. Preferably it is the ratio used as 0.3 to 1.2 equivalent.

Synthesis reaction of polyamic acid is performed in organic solvent, Preferably it is -20 degreeC-150 degreeC, More preferably, it is performed on the temperature conditions of 0-100 degreeC.

The organic solvent is not particularly limited as long as it can dissolve the polyamic acid synthesized. For example, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide Aprotic polar solvents such as dimethyl sulfoxide, γ-butyrolactone, tetramethylurea and hexamethylphosphortriamide; and phenol solvents such as m-cresol, xylenol, phenol, and halogenated phenol. Further, the amount of use of the organic solvent (α) is preferably such that the total amount (β) of the tetracarboxylic dianhydride and the diamine compound is 0.1 to 30% by weight relative to the total amount (α + β) of the reaction solution. to be.

In addition, the organic solvent can be used in combination without causing polyamic acid to form alcohols, ketones, esters, ethers, halogenated hydrocarbons, hydrocarbons and the like which are poor solvents of polyamic acid. As a specific example of such a poor solvent, for example, methyl alcohol, ethyl alcohol, isopropyl alcohol, cyclohexanol, 4-hydroxy-4-methyl-2-pentanone (diacetone alcohol), ethylene glycol, propylene glycol , 1,4-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 methoxy Propionate, ethyl ethoxy propionate, diethyl oxalate, diethyl malonate, diethyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n-propyl ether, ethylene glycol-i-propyl ether, ethylene Glycol-n-butyl ether, ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, Diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, tetrahydrofuran, dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane And trichloroethane, chlorobenzene, o-dichlorobenzene, hexane, heptane, octane, benzene, toluene, xylene and the like.

The reaction solution which melt | dissolves a polyamic acid as mentioned above is obtained. The reaction solution is poured into a large amount of poor solvent to obtain a precipitate, and the polyamic acid can be obtained by drying the precipitate under reduced pressure. Moreover, polyamic acid can be refine | purified by performing the process of dissolving this polyamic acid again in an organic solvent and continuing to precipitate with a poor solvent once or several times.

[Imidation of Polyamic Acid]

The imidized polymer can be synthesized by dehydrating and closing the polyamic acid. The imidation polymer used for this invention has a structure whose ratio (it is also called "imidation ratio") of the repeating unit which has the imide ring in all the repeating units of amic acid and an imide is 60 mol% or more. By using the polymer whose imidation ratio is 60 mol% or more, More preferably, 75 mol% or more, the liquid crystal aligning agent which can form the liquid crystal aligning film with high voltage retention is obtained.

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

The reaction temperature in the method of heating the polyamic acid of said (i) becomes like this. Preferably it is 50-200 degreeC, More preferably, it is 60-170 degreeC. When reaction temperature is less than 50 degreeC, dehydration ring-closure reaction does not fully advance, and when reaction temperature exceeds 200 degreeC, the molecular weight of the imidation polymer obtained may fall.

On the other hand, in the method of adding the dehydrating agent and the dehydrating ring-closure catalyst in the solution of the polyamic acid of the above (ii), for example, acid anhydrides such as acetic anhydride, propionic anhydride and trifluoroacetic anhydride can be used. Although the usage-amount of a dehydrating agent changes with a desired imidation ratio, it is preferable to set it as 0.01-20 mol with respect to 1 mol of repeating units of a polyamic acid. As the dehydration ring closure catalyst, tertiary amines such as pyridine, collidine, lutidine and triethylamine can be used, for example. However, it is not limited to these. It is preferable that the usage-amount of a dehydration ring-closure catalyst shall be 0.01-10 mol with respect to 1 mol of dehydrating agents used. The imidation ratio can be increased as the usage-amount of the above-mentioned dehydrating agent and dehydrating ring closure agent increases. Moreover, the organic solvent illustrated as what is used for the synthesis | combination of a polyamic acid as an organic solvent used for dehydration ring-closure reaction is mentioned. And the reaction temperature of dehydration ring-closure reaction becomes like this. Preferably it is 0-180 degreeC, More preferably, it is 10-150 degreeC. Moreover, the imidation polymer obtained by performing the operation similar to the purification method of polyamic acid about the reaction solution obtained in this way can be refine | purified.

Logarithmic viscosity of the polymer

The value of the logarithmic viscosity (η _ln ) of the imidized polymer obtained as mentioned above becomes like this. Preferably it is 0.05-10 dl / g, More preferably, it is 0.05-5 dl / g.

The value of the logarithmic viscosity (η _ln ) in the present invention uses N-methyl-2-pyrrolidone as a solvent, and the viscosity is measured at 30 ° C with respect to a solution having a concentration of 0.5 g / 100 ml. It is obtained by 1.

[Liquid crystal aligning agent]

The liquid crystal aligning agent of the present invention is preferably formed by dissolving the imidized polymer in an organic solvent. The temperature at the time of manufacturing the liquid crystal aligning agent of this invention becomes like this. Preferably it is 0 degreeC-200 degreeC, More preferably, it is 20 degreeC-60 degreeC.

As an organic solvent which comprises the liquid crystal aligning agent of this invention, N-methyl- 2-pyrrolidone, (gamma) -butyrolactone, (gamma) -butyrolactam, N, N- dimethylformamide, N, N, for example -Dimethylacetamide, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxy propionate, ethyl ethoxy propionate, ethylene glycol methyl ether, Ethylene glycol ethyl ether, ethylene glycol-n-propyl ether, ethylene glycol-i-propyl ether, ethylene glycol-n-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl Ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, and the like. Can be mentioned.

Although solid content concentration in the liquid crystal aligning agent of this invention is selected in consideration of viscosity, volatility, etc., Preferably it exists in the range of 1 to 10 weight%. The liquid crystal aligning agent of this invention is apply | coated to the surface of a board | substrate, and the coating film used as a liquid crystal aligning film is formed. When the solid content concentration is less than 1% by weight, the film thickness of the coating film becomes too thin to obtain a good liquid crystal alignment film. When the solid content concentration exceeds 10% by weight, the film thickness of the coating film is too thick to obtain a good liquid crystal alignment film. None, the viscosity of a liquid crystal aligning agent increases, and coating property falls.

The liquid crystal aligning agent of this invention may contain the functional silane containing compound and an epoxy compound from a viewpoint of improving the adhesiveness to the board | substrate surface in the range which does not impair the target physical property. As a functional silane containing compound, 3-aminopropyl trimethoxysilane, 3-aminopropyl triethoxysilane, 2-aminopropyl trimethoxysilane, 2-aminopropyl triethoxysilane, N- ( 2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltrier Methoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-tri Methoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4,7-triazadecan, 10-triethoxysilyl-1,4,7-triazadecan, 9-trimethoxysilyl- 3,6-diazanyl acetate, 9-triethoxysilyl-3,6-diazanyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-ami Propyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis (oxyethylene) -3-aminopropyltrimethoxysilane, N -Bis (oxyethylene) -3-aminopropyltriethoxysilane, etc. are mentioned.

As the epoxy compound, for example, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether , Neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3,5 , 6-tetraglycidyl-2,4-hexanediol, N, N, N ', N',-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidyl Amino methyl) cyclohexane, N, N, N ', N',-tetraglycidyl-4,4'-diaminodiphenylmethane, 3- (N-allyl-N-glycidyl) aminopropyltrimeth Methoxysilane, 3- (N, N- diglycidyl) aminopropyltrimethoxysilane, etc. are mentioned.

The compounding ratio of these functional silane containing compounds and epoxy compounds becomes like this. Preferably it is 60 weight part or less, More preferably, it is 0.1-40 weight part with respect to 100 weight part of polymers. In particular, since there is an effect expected by adding an epoxy compound, it is preferable. Particularly preferred epoxy compounds are N, N, N ', N',-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N ', N',-tetraglycidyl-4,4'-diaminodiphenylmethane, 3- (N-allyl-N-glycidyl) aminopropyltrimethoxysilane, 3- (N, N- Nitrogen-containing epoxy compounds such as diglycidyl) aminopropyltrimethoxysilane.

<Example>

Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not restrict | limited to these Examples.

[Method of measuring imidation ratio of imidized polymer]

The imidized polymer was dried under reduced pressure at room temperature, dissolved in deuterated dimethyl sulfoxide, and ¹ H-NMR was measured at room temperature using tetramethylsilane as a reference material to obtain the following formula (2).

Imidation ratio (%) = (1-A ¹ / A ² × α) × 100

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

A ² : peak area derived from other protons

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

[Method of Manufacturing Liquid Crystal Display Element]

A liquid crystal aligning agent was printed on the glass substrate with an ITO (A) which has the processus | protrusion formed using positive type resist, and the glass substrate (B) which has an ITO pattern, respectively, at 80 degreeC for 1 minute, after that, in 200 degree | times 200 It dried at 1 degreeC and formed the coating film of 600 Å of dry film thickness.

After manufacturing two board | substrates with a liquid crystal aligning film as mentioned above, apply | coating the epoxy resin adhesive which contains the aluminum oxide sphere of 5.5 micrometers of particle diameters by the screen printing method in the outer edge part of the board | substrate (B), Two board | substrates were bonded so that it might become a positional relationship like FIG.

The liquid crystal MLC-6608 by Merck company was injected-filled in the cell gap partitioned by the surface of the board | substrate and the adhesive agent of the outer edge part, and then the injection hole was sealed with the epoxy type adhesive agent, and the vertically-aligned liquid crystal display element was manufactured.

[Vertical orientation]

When no voltage was applied under the cross nicol, the light leaked when visually observed in the vertical direction with respect to the liquid crystal display element was small, and when black display was made, it was determined as "good".

[Voltage retention rate]

After applying a voltage of 5 V to a liquid crystal display element at 60 degreeC by 60 microseconds of application time and 2000 milliseconds of span, the voltage retention after 2000 milliseconds after application | release cancellation was measured. The measurement apparatus used VHR-1 by Toyo Technica Co., Ltd.

[Applicability of Liquid Crystal Alignment Agent]

After forming and baking a coating film by the printing method, it judged by visual observation, and there was no cratering and coating unevenness, and it was called "good | favorableness."

Synthesis of Polymer

<Synthesis Examples 1 to 14>

Diamine and tetracarboxylic dianhydride were added to N-methyl- 2-pyrrolidone in this order so that solid content concentration might be 20% by the composition shown in following Table 1, and it reacted for 4 hours, stirring at room temperature. Subsequently, this solution was poured into a large excess of pure water to precipitate the reaction product, and then the solid was separated, washed with pure water, and dried at 40 ° C. for 15 hours under reduced pressure to obtain a white powdery polyamic acid. The polyamic acid thus obtained was dissolved in N-methyl-2-pyrrolidone so as to have a solid content concentration of 7%, and pyridine and acetic anhydride were each added at a ratio shown in Table 1 with respect to 1 mol of repeating units, and then 110 It heated at 4 degreeC for 4 hours, and performed dehydration ring-closure reaction. The obtained reaction solution was poured into a large amount of pure water to precipitate the reaction product. Thereafter, the solid was separated, washed with pure water, and dried at 40 ° C. for 15 hours under reduced pressure to obtain an imidized polymer (white powder). The diamine, tetracarboxylic dianhydride composition, and logarithmic viscosity of the imidized polymer and polyamic acid thus obtained are shown in Table 1.

In addition, only the synthesis example 14 did not perform a dehydration ring-closure reaction, and made polyamic acid the final product.

The number in () is mmol, and the symbol of the diamine type and tetracarboxylic dianhydride type is as follows.

Acid Anhydride A: 2,3,5-tricarboxycyclopentylacetic dianhydride

Diamine A: p-phenylenediamine

Diamine B: diamine represented by formula (34)

Diamine C: 4,4'-diaminodiphenylmethane

Diamine D: diamine represented by formula (14)

Diamine E: diamine represented by formula (18)

<Examples 1 to 9 and Comparative Examples 1 to 5>

N, N to 94 g of a mixed solvent having gamma butyrolactone (BL), N-methyl-2-pyrrolidone (NMP) and butyl cellosolve (BC) in a weight ratio BL / NMP / BC = 40/30/30 After adding 1 g of, N ', N'-tetraglycidyl-4,4'-diaminodiphenylmethane, the imidized polymer (PI-1 to PI-13) or poly obtained in Synthesis Examples 1 to 14 5g of 1 type of amic acid (PA-14) was mixed and stirred, and the vertically-aligned liquid crystal aligning agent of this invention was obtained. The liquid crystal display element was manufactured using this liquid crystal aligning agent, and various evaluation was performed. The results are shown in Table 2 below.

According to the liquid crystal aligning agent of this invention, the vertical alignment property is favorable, applicability | paintability is favorable, and the vertical alignment type liquid crystal aligning film with high voltage retention is obtained. In addition, the liquid crystal aligning agent of this invention "Liquid crystal" Vol. 3, No. 2, 117 (1999) and Japanese Patent Laid-Open No. Hei 11-258605 to form projections on the ITO to control the alignment direction of the liquid crystal (see Fig. 1), or "liquid crystal" Vol. 3, No. 4, 272 (1999) can be preferably used as a vertical alignment type liquid crystal display element of the EVA system (see FIG. 2) for studying the electrode structure and controlling the orientation direction.

Claims (4)

An amid acid repeating unit represented by the following general formula (1a) and an imide repeating unit represented by the following general formula (1b), The said imide repeating unit contains the imidation polymer which occupies 60 mol% or more with respect to the sum total of these repeating units. The vertical alignment liquid crystal aligning agent characterized by the above-mentioned. <Formula 1a>

In formula, P <^1> is a tetravalent organic group, Q <^1> is at least 1 sort (s) of bivalent organic groups represented by following formula (2a) or (2b), and 1 sort (s) of divalent organic group represented by following formula (2c) or 2d, respectively. It includes a combination with the above. <Formula 1b>

In formula, P <^2> is a tetravalent organic group, Q <^2> is at least 1 sort (s) of bivalent organic groups represented by following General formula (2a) or 2b, and 1 sort (s) of divalent organic group represented by following Formula (2c) or (2d), respectively. It includes a combination with the above. <Formula 2a>

Wherein X ¹ is a single bond, -O-, -CO-, -COO-, -OCO-, -NHCO-, -CONH-, -S- or an arylene group, R ¹ is an alkyl group having 10 to 20 carbon atoms , A monovalent organic group having 4 to 40 carbon atoms having an alicyclic skeleton, or a monovalent organic group having 6 to 20 carbon atoms having a fluorine atom. <Formula 2b>

Wherein, X ² represents a single bond, -O-, -CO-, -COO-, -OCO-, -NHCO-, -CONH-, -S- , or an arylene group, R ² is alkyl group which has an alicyclic skeleton It is a divalent organic group of 4-40. <Formula 2c> Wherein X ³ is -O-, -CO-, -COO-, -OCO-, -NHCO-, -CONH-, -S- or an arylene group, R ³ is an alkylene group having 1 to 24 carbon atoms or halogenated Alkylene group. <Formula 2d>

In formula, R <^4> is a C1-C24 alkylene group or halogenated alkylene group. The method according to claim 1, wherein based on the sum of Q ¹ in formula (1a) and Q ² in formula (1b), Q ¹ and Q ² contain 7 mol% or more of a divalent organic group represented by formula (2a) and formula (2b), respectively. Vertically-aligned liquid crystal aligning agent. The divalent organic group according to claim 1 or 2, wherein Q ¹ and Q ² are represented by Formula 2c and Formula 2d, respectively, based on the sum of Q ¹ in Formula 1a and Q ² in Formula 1b. The vertically-aligned liquid crystal aligning agent containing mol% or more. The liquid crystal aligning film obtained from the vertically-aligned liquid crystal aligning agent of any one of Claims 1-3 is provided. The liquid crystal display element characterized by the above-mentioned.

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