KR20140027550A

KR20140027550A - Liquid crystal aligning agent, liquid crystal alignment film, and liquid crystal display element

Info

Publication number: KR20140027550A
Application number: KR1020147003024A
Authority: KR
Inventors: 심페이 니이츠; 고 오노
Original assignee: 닛산 가가쿠 고교 가부시키 가이샤
Priority date: 2011-07-12
Filing date: 2012-07-10
Publication date: 2014-03-06
Also published as: CN103797408B; JP5773177B2; CN107090301A; CN103797408A; JPWO2013008822A1; KR101610558B1; TWI455962B; WO2013008822A1; TW201323484A

Abstract

Liquid crystal aligning agent containing following specific polymer (A) and specific polymer (B).
Specific polymer (A): tetracarboxylic dianhydride component containing bicyclo [3,3,0] octane-2,4,6,8-tetracarboxylic dianhydride, and 4,4'-diamino Polyamic acid obtained by making the diamine component containing at least 1 of the diamine compound represented by diphenylamine and 3, 6- diamino carbazole react.
Specific polymer (B): The polyimide precursor which has a structural unit represented by following formula (7).

(In formula (7), R represents a hydrogen atom or an alkyl group, Y represents a tetravalent organic group, X represents a divalent organic group, and 10-100 mol% of X is in formula (8)-(10) It is a divalent organic group or paraphenylene group which has either in a structure.)

(M <_1> is an integer of 2-18 in a formula (8).)

(In Formula (9), one or more of arbitrary hydrogen atoms on a benzene ring may be substituted by monovalent organic groups other than a primary amino group, and m <_2> is an integer of 1-8.)

(In Formula (10), one or more of arbitrary hydrogen atoms on a benzene ring may be substituted by monovalent organic groups other than a primary amino group, and m <_3> is an integer of 1-4.)

Description

Liquid crystal aligning agent, a liquid crystal aligning film, and a liquid crystal display element {LIQUID CRYSTAL ALIGNING AGENT, LIQUID CRYSTAL ALIGNMENT FILM, AND LIQUID CRYSTAL DISPLAY ELEMENT}

This invention relates to the liquid crystal aligning agent used when forming a liquid crystal aligning film, a liquid crystal aligning film, and the liquid crystal display element using the same.

Liquid crystal display elements are now widely used as display devices. Although the liquid crystal aligning film which is a structural member of a liquid crystal display element is a film | membrane which arranges a liquid crystal uniformly, when liquid crystal alignability is inadequate, it will become easy to cause display defects called display unevenness and an afterimage. The generation of display defects may involve ionic impurities in the liquid crystal, and a proposal similar to that of Patent Document 1 has been made as a method of reducing the impurities.

Moreover, in a liquid crystal aligning film, it is common to perform the orientation process called rubbing which rubs the surface of a polymer film with cloth. However, when rubbing resistance of a liquid crystal aligning film is inadequate, a film | membrane may be scraped, a flaw and dust generate | occur | produce, or the film | membrane itself peels, and the display quality of a liquid crystal display element is reduced. Therefore, high rubbing tolerance is calculated | required by the liquid crystal aligning film, and the method as shown by patent documents 2-5 is proposed.

Moreover, in order to obtain the liquid crystal display element of a high display quality, it is also important to show high luminance. Therefore, what has higher transmittance | permeability is calculated | required by the liquid crystal aligning film.

On the other hand, when the volume resistivity of a liquid crystal aligning film is high, there exists a problem that accumulated charge becomes difficult to relieve and it takes time to erase an afterimage. As a method of shortening an afterimage erasing time, the method of using the orientation film with low volume resistivity like patent document 6 is proposed.

Japanese Unexamined Patent Publication No. 2002-323701 Japanese Patent Application Laid-Open No. 7-120769 Japanese Patent Application Laid-Open No. 9-146100 Japanese Patent Application Laid-Open No. 2008-90297 Japanese Patent Application Laid-Open No. 9-258229 International Publication No. 2004/053583

However, in recent years, while high-quality liquid crystal display devices are being advanced, a strong backlight tends to be used. Therefore, it is said that not only the volume resistivity of a liquid crystal aligning film is low, but also that a volume resistivity does not change with light. For example, in the liquid crystal aligning film in a liquid crystal display element, the part which light is hard to reach compared with another part may exist by presence of wiring, a black matrix, etc. may exist. When the volume resistivity of a liquid crystal aligning film changes with light, the whole element will not show uniform afterimage characteristic, and it will be observed as display defects, such as an afterimage and display unevenness.

This invention is made | formed in view of the said situation, The liquid crystal aligning film which is excellent in liquid crystal orientation, rubbing tolerance, voltage holding | maintenance characteristic, and charge accumulation characteristic, has a small amount of ionic impurity, high transmittance | permeability, and small change of the volume resistivity by light. It is providing the liquid crystal aligning agent which can obtain the liquid crystal aligning film, a liquid crystal aligning film, and a display defect, the fall of contrast, the afterimage of a display, etc. which are hard to produce.

MEANS TO SOLVE THE PROBLEM This inventor discovered that the said objective can be achieved by the liquid crystal aligning agent which contained the specific polymer (A) and the specific polymer (B) as a result of earnestly researching in order to achieve the said objective.

Thus, the present invention has the following points.

1. Liquid crystal aligning agent containing following specific polymer (A) and specific polymer (B).

Specific polymer (A): At least 1 of the tetracarboxylic dianhydride component containing the dianhydride of tetracarboxylic acid represented by following formula (1), and the diamine compound represented by following formula (5) and (6) Polyamic acid obtained by making the diamine component containing react.

[Chemical Formula 1]

(2)

(In Formula (5) and (6), one or more of arbitrary hydrogen atoms on a benzene ring may be substituted by monovalent organic groups other than a primary amino group.)

Specific polymer (B): The polyimide precursor which has a structural unit represented by following formula (7).

(3)

(In formula (7), R represents a hydrogen atom or an alkyl group, Y represents a tetravalent organic group, X represents a divalent organic group, and 10-100 mol% of X is a following formula (8)-(10) It is a divalent organic group or paraphenylene group which has either in a structure.)

[Chemical Formula 4]

(M <_1> is an integer of 2-18 in a formula (8).)

[Chemical Formula 5]

[Chemical Formula 6]

2. Tetracarboxylic dianhydride component in specific polymer (A) is tetracarboxylic acid represented by the following anhydride of tetracarboxylic acid represented by following formula (1), and following formula (2)-(4) The liquid crystal aligning agent of 1 which consists of dianhydride of at least 1 sort (s) of compound chosen from.

[Formula 7]

(In formula (3), R <^1> , R <^2> , R <^3> , R <^4> represents a hydrogen atom or a C1-C3 alkyl group each independently.)

3. Tetracarboxylic dianhydride component in specific polymer (A) is 10-100 mol% of dianhydride of tetracarboxylic acid represented by Formula (1), and tetra is represented by Formula (2)-(4) The liquid crystal aligning agent of 2 which consists of 0-90 mol% of dihydrides of at least 1 sort (s) of compound chosen from carboxylic acid.

4. Tetracarboxylic dianhydride component in specific polymer (A) is 10-100 mol% of dianhydride of tetracarboxylic acid represented by Formula (1), and the tetracarboxylic acid represented by Formula (3). The liquid crystal aligning agent of 3 consisting of 2 anhydrides 0-90 mol%.

5. Liquid crystal aligning agent in any one of 1-4 whose 20-100 mol% of Y of Formula (7) is a tetravalent organic group which has an aromatic structure.

6. Liquid crystal aligning film obtained using liquid crystal aligning agent in any one of 1-5.

The liquid crystal display element provided with the liquid crystal aligning film of 7. 1-6.

By using the liquid crystal aligning agent of this invention, the liquid crystal aligning film which is excellent in liquid crystal orientation, rubbing tolerance, voltage holding | maintenance characteristic, and charge accumulation characteristic, has a small amount of ionic impurity, high transmittance | permeability, and small change of the volume resistivity by light. It is possible to provide a high quality liquid crystal display element.

Hereinafter, the present invention will be described in detail.

The liquid crystal aligning agent of this invention is a composition used for forming a liquid crystal aligning film, The tetracarboxylic dianhydride component containing the dianhydride of tetracarboxylic acid represented by following formula (1), and following formula (5) ) And polyimide having a polyamic acid (hereinafter also referred to as a specific polymer (A)) obtained by reacting a diamine component containing at least one of the diamine compounds represented by (6) and the structural unit represented by General formula (7) It is characterized by containing a precursor (henceforth a specific polymer (B)).

[Formula 8]

[Chemical Formula 9]

[Formula 10]

(In General Formula (7), R represents a hydrogen atom or an alkyl group, Y represents a tetravalent organic group, X represents a divalent organic group, and 10-100 mol% of X is a following formula (8)-(10) ) Is a divalent organic group or paraphenylene group having any of the structures.)

(11)

(M <_1> is an integer of 2-18 in a formula (8).)

[Chemical Formula 12]

[Chemical Formula 13]

As for the ratio of a specific polymer (A) and a specific polymer (B), it is preferable that a specific polymer (A) is 10 to 95 weight% with respect to the total amount of a specific polymer (A) and a specific polymer (B), More preferably, Is 60 to 90% by weight. When there are too few specific polymers (A), the charge accumulation characteristic and rubbing tolerance of a liquid crystal aligning film may deteriorate, and when there are too few specific polymers (B), liquid crystal alignability may deteriorate. 1 type may be sufficient as specific polymer (A) and specific polymer (B) contained in the liquid crystal aligning agent of this invention, respectively and may be two or more types.

The tetracarboxylic dianhydride component used for manufacture of a specific polymer (A) contains the dianhydride of tetracarboxylic acid represented by following formula (1).

[Formula 14]

Specifically, the tetracarboxylic dianhydride component in a specific polymer (A) is the tetracarboxylic dianhydride represented by following formula (1), and the tetracarboxylic acid represented by following formula (2)-(4) It is preferable that it consists of the anhydride of at least 1 sort (s) of compound chosen from an acid.

[Chemical Formula 15]

(In formula (2), R <^1> , R <^2> , R <^3> , R <^4> represents a hydrogen atom or a C1-C3 alkyl group each independently.)

As a composition ratio of the preferable tetracarboxylic dianhydride component in a specific polymer (A), the dihydride of tetracarboxylic acid represented by Formula (1) is 10-100 mol% of the whole tetracarboxylic dianhydride component. And the anhydride of the at least 1 sort (s) of compound chosen from the tetracarboxylic acid represented by Formula (2)-(4) is 0-90 mol% of the whole tetracarboxylic dianhydride component. More preferably, the anhydride of the tetracarboxylic acid represented by Formula (1) is 10-90 mol% of the whole tetracarboxylic dianhydride component, and tetracarboxylic acid represented by Formula (2)-(4) The anhydride of the at least 1 sort (s) of compound chosen from is 10-90 mol% of the whole tetracarboxylic dianhydride component. More preferably, the anhydride of the tetracarboxylic acid represented by Formula (1) is 20-80 mol% of the whole tetracarboxylic dianhydride component, and the tetracarboxylic acid represented by Formula (2)-(4) The anhydride of at least 1 sort (s) of compound chosen from is 20-80 mol% of the whole tetracarboxylic dianhydride component. Especially preferably, the anhydride of the tetracarboxylic acid represented by Formula (1) is 25-75 mol% of the whole tetracarboxylic dianhydride component, and the tetracarboxylic acid represented by Formula (2)-(4) The anhydride of at least 1 sort (s) of compound chosen from is 25-75 mol% of the whole tetracarboxylic dianhydride component.

The combination of preferable tetracarboxylic dianhydride component is a dianhydride of the tetracarboxylic acid represented by Formula (1), and the anhydride of tetracarboxylic acid represented by Formula (1) from a liquid-crystal orientation.

The diamine component used for manufacture of a specific polymer (A) contains at least 1 of the diamine compound represented by following formula (5) and the diamine compound represented by following formula (6).

[Chemical Formula 16]

Formula (5) is a diamine which has a diphenylamine group of 4,4 'bond from a viewpoint of liquid-crystal orientation, Preferably, Formula (6) is a car of 3,6 bond from a viewpoint of liquid-crystal orientation. It is a diamine having a bazole group.

In the formula (5) or (6), one or a plurality of arbitrary hydrogen atoms on the benzene ring may be substituted with monovalent organic groups other than the primary amino group. As this monovalent organic group, a C1-C20 alkyl group, a C2-C20 alkenyl group, a C1-C20 alkoxy group, a C1-C20 fluorine-containing alkyl group, a C2-C20 fluorine-containing alkenyl group, carbon number The group which consists of a 1-20 fluorine-containing alkoxy group, a cyclohexyl group, a phenyl group, a fluorine atom, these combinations, etc. are mentioned, From a viewpoint of liquid crystal alignability, a C1-C4 alkyl group, a C2-C4 alkenyl group, The monovalent organic group chosen from a C1-C4 alkoxy group, a C1-C4 fluorine-containing alkyl group, a C2-C4 fluorine-alkenyl group, and a C1-C4 fluorine-containing alkoxy group is preferable. As more preferable structures of Formulas (5) and (6), the hydrogen atom on the benzene ring is unsubstituted.

As for the ratio with respect to the total diamine component of the total amount of the diamine compound represented by Formula (5) and the diamine compound represented by Formula (6) in a specific polymer (A), 10-100 mol% is preferable, More preferably, Is 60-100 mol%. By setting the total amount of the diamine compound represented by the formula (5) and the diamine compound represented by the formula (6) to 10 mol% or more, the volume resistivity can be effectively lowered, the volume resistivity is low, and the change in volume resistivity due to light is small. Obtaining a polyamic acid becomes easy, Furthermore, voltage retention characteristic is favorable and it becomes easy to provide the outstanding charge accumulation characteristic and rubbing tolerance to a liquid crystal aligning film.

In the diamine compound represented by Formula (5) or Formula (6), 4,4'- diamino diphenylamine, 3, from a viewpoint of the liquid crystal aligning property when it is set as the reactivity with tetracarboxylic dianhydride and a liquid crystal aligning film. 6-diaminocarbazole is particularly preferred.

In a specific polymer (A), in addition to the diamine compound represented by Formula (5) and Formula (6), in the range which does not impair the effect of this invention, it is other than the diamine compound represented by Formula (5) and Formula (6). It is also possible to contain another diamine compound. As another diamine compound, the diamine compound shown by following formula (15) is mentioned. Although the specific example is shown below, it is not limited to these.

[Chemical Formula 17]

As a diamine compound represented by Formula (15) in which A has a nitrogen atom, 2,3-diaminopyridine, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 2 , 4-diamino-6-hydroxypyrimidine, 2,4-diamino-1,3,5-triazine, 2,4-diamino-1,3,5-triazine, 2,4-dia Mino-6-isopropoxy-1,3,5-triazine, 2,4-diamino-6-methoxy-1,3,5-triazine, 2,4-diamino-6-phenyl-1 , 3,5-triazine, 2,6-diaminopurine, 1,4-bis (3-aminopropyl) piperazine, 2,4-diamino-5-phenylthiazole, 3,5-diamino- 1,2,4-triazole, 3,6-diaminoacridine, acrinol, 2,5-bis (4-aminophenyl) -1,3,4-oxadiazole, diethylenetriamine, tri Ethylenetetraamine, 3,3'-diamino-dipropylamine, pentaethylenehexaamine, N, N-bis (3-aminopropyl) methylamine, 4,4'-diaminobenzanilide, 2,6-dia Mino-4-nitrotoluene, N, N'-bis (4-aminophenyl) -N-phenyla , N, and the like N'- bis (4-aminophenyl) -N- methyl amine, 4,4'-diaminodiphenyl urea.

As an example of the diamine compound represented by Formula (15) which is an aliphatic diamine, diaminomethane, 1, 2- diamino ethane, 1, 3- diamino propane, 1, 4- diamino butane, 1, 6- diamino hexane , 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,3-diamino-2,2-dimethylpropane, 1, 4-diamino-2,2-dimethylbutane, 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-methylnonane, 2,11-diaminododecane, 1,12-diaminooctadecane, 1,2- Bis (3-aminopropoxy) ethane etc. are mentioned.

As an example of the diamine compound represented by Formula (15) which is an alicyclic diamine, 1, 4- diamino cyclohexane, 1, 3- diamino cyclohexane, 4, 4'- diamino dicyclohexyl methane, 4, 4 ' -Diamino-3,3'-dimethyldicyclohexylmethane, isophorone diamine, etc. are mentioned.

As an example of the diamine compound represented by Formula (15) which is a carbocyclic aromatic diamine, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, diaminotoluenes (for example, 2, 4- dia) Minotoluene), 1,4-diamino-2-methoxybenzene, 2,5-diaminoxylene, 1,3-diamino-4-chlorobenzene, 1,4-diamino-2,5-dichloro Benzene, 1,4-diamino-4-isopropylbenzene, 4,4'-diaminodiphenyl-2,2'-propane, 4,4'-diaminodiphenylmethane, 2,2'-diamino Stilbene, 4,4'-diaminostilbene, 4,4'-diaminodiphenylether, 4,4'-diphenylthioether, 4,4'-diaminodiphenylsulfone, 3,3'- Diaminodiphenylsulfone, 4,4'-diaminobenzoic acid phenyl ester, 2,2'-diaminobenzophenone, 4,4'-diaminobenzyl, bis (4-aminophenyl) phosphine oxide, bis (3 -Aminophenyl) methylsulpin oxide, bis (4-aminophenyl) phenylphosphine oxide, bis (4-aminophenyl) cyclohexylphosphineoxa De, 1,8-diaminonaphthalene, 1,5-diaminonaphthalene, 1,5-diaminoanthraquinone, diaminofluorene, bis (4-aminophenyl) diethylsilane, bis (4-aminophenyl) Dimethylsilane, bis (4-aminophenyl) tetramethyldisiloxane, 3,4'-diaminodiphenylether, benzidine, 2,2'-dimethylbenzidine, 2,2-bis [4- (4-aminophenoxy ) Phenyl] propane, bis [4- (4-aminophenoxy) phenyl] sulfone, 4,4'-bis (4-aminophenoxy) biphenyl, 2,2-bis [4- (4-aminophenoxy ) Phenyl] hexafluoropropane, 1, 4-bis (4-amino phenoxy) benzene, 1, 3-bis (4-amino phenoxy) benzene, etc. are mentioned.

As a diamine compound represented by Formula (15) which has the characteristic which A raises the pretilt angle of a liquid crystal, 1-dodecyloxy-2,4-diaminobenzene and 1-hexadecyloxy-2,4-diaminobenzene , 1-octadecyloxy-2,4-diaminobenzene, 1,1-bis (4-aminophenyl) cyclohexane, 2,2-bis [4- (4-aminophenoxy) phenyl] octane, 4 , 4'-diamino-3-dodecyldiphenylether, 4- (4-trans-n-heptylcyclohexylphenoxy) -1,3-diaminobenzene, 4- (4-trans-n-pentylcyclohexyl Phenoxy) -1,3-diaminobenzene, 4-trans-n-pentylbicyclohexyl-3,5-diaminobenzoate, etc. are mentioned.

A specific polymer (B) is a polyimide precursor which has a structural unit (repeated unit) represented by following formula (7). Moreover, a polyimide precursor is polyamic acid and polyamic acid ester.

[Chemical Formula 18]

The specific polymer (B) may be a polyimide precursor having a structural unit represented by formula (7) in which each of R, X, and Y each has only one kind and has the same structure. It may be a polyimide precursor having a structural unit represented by a plurality of types of formulas (7). In addition, the polyimide precursor which also has a structure other than the structural unit represented by Formula (7) may be sufficient as a specific polymer (B). That is, the specific polymer (B) may be a polyimide precursor composed of a structural unit represented by formula (7) having the same structure, or may be a polyimide precursor composed of structural units represented by formula (7) having a different structure, and may also have the same structure. Or the polyimide precursor which has structures other than the structural unit represented by Formula (7) of a different structure and the structural unit represented by Formula (7) may be sufficient.

In formula (7), R is a hydrogen atom or an alkyl group. As an alkyl group, a C1-C6 alkyl group is mentioned.

In Formula (7), X is a divalent organic group, and as above-mentioned, one type may be sufficient and two or more types may be mixed, but at least 1 type of X is a following formula (8)-(10 It is necessary to be a divalent organic group or a paraphenylene group which has either of them in a structure.

[Chemical Formula 19]

[Chemical Formula 20]

[Chemical Formula 21]

And the ratio of the bivalent organic group or paraphenylene group (henceforth a "specific structure") which has either of these formula (8)-(10) in structure in X of Formula (7) is 10. It is-100 mol%, Preferably it is 50-100 mol%. When this ratio is too small, liquid crystal alignability may deteriorate. Although the structure of X other than the divalent organic group or paraphenylene group which has either of these formula (8)-(10) in a structure is not specifically limited, For example, in order to raise the pretilt angle of a liquid crystal, long chain The divalent organic group which has a substituent with which the effect of raising a tilt angle is known, such as an alkyl group, a perfluoroalkyl group, and a steroid skeleton group, is mentioned.

Although m <_1> is an integer of 2-18 in a formula (8), from a viewpoint of liquid crystal alignability and heat resistance, Preferably it is 3-12, More preferably, it is 4-8. Moreover, it is preferable that the bivalent organic group which has Formula (8) in a structure further contains an aromatic ring, As a specific example of the bivalent organic group which has Formula (8) in a structure, following formula (11)- Although (14) is mentioned, it is not limited to these.

[Chemical Formula 22]

In Formula (11)-(14), m <_1> is an integer of 2-18, Preferably it is 3-12, More preferably, it is 4-8.

In formula (9), although m <_2> is an integer of 1-8, 1-3 are preferable from a viewpoint of a voltage holding | maintenance characteristic, More preferably, it is 1 or 2.

In formula (10), although m <_3> is an integer of 1-4, it is 1 or 2 from a viewpoint of the stability of a polyamic-acid solution.

In formula (9), (10), (11)-(14) and a paraphenylene group, even if one or several arbitrary hydrogen atoms on a benzene ring are substituted by monovalent organic groups other than a primary amino group, do. As monovalent organic groups other than this primary amino group, C1-C20 alkyl group, C2-C20 alkenyl group, C1-C20 alkoxy group, C1-C20 fluorine-containing alkyl group, C2-C20 containing The fluorine alkenyl group, a C1-C20 fluorine-containing alkoxy group, a cyclohexyl group, a phenyl group, the group which consists of a fluorine atom, and these combinations, etc. are mentioned, A C1-C4 alkyl group, C2-C2 from a liquid-crystal orientation property are mentioned. The monovalent organic group chosen from an alkenyl group of 4, a C1-C4 alkoxy group, a C1-C4 fluorine-containing alkyl group, a C2-C4 fluorine-containing alkenyl group, and a C1-C4 fluorine-containing alkoxy group is preferable. . As a more preferable structure, the hydrogen atom on a benzene ring is unsubstituted.

Y in Formula (7) is a tetravalent organic group, and as mentioned above, one type may be sufficient and two or more types may be mixed. Although the structure of Y is not specifically limited, From a viewpoint of raising liquid crystal alignability further, it is preferable that at least 1 type of Y is a tetravalent organic group which has an aromatic structure (namely, an aromatic group). In this case, the preferable ratio of the tetravalent organic group which has an aromatic structure in Y of Formula (7) is 20-100 mol%, More preferably, it is 50-100 mol%. As the tetravalent organic group having an aromatic structure, pyromellitic acid, 3,3 ', 4,4'-biphenyltetracarboxylic acid, 3,3', 4,4'-benzophenonetetracarboxylic acid, bis ( The structure remove | excluding four carboxyl groups from tetracarboxylic acids, such as 3, 4- dicarboxyphenyl) ether, bis (3, 4- dicarboxyphenyl) sulfone, and 2,3,6,7- naphthalene tetracarboxylic acid, is preferable. Do.

In addition, Y of Formula (7) is 1,2,3,4-cyclobutanetetracarboxylic acid, 2,3,5-tricarboxycyclopentyl acetic acid, 3,4-dicarboxy-1,2,3, In the case of the structure remove | excluding four carboxyl groups from tetracarboxylic acids, such as 4-tetrahydro- 1-naphthalene succinic acid and bicyclo [3,3,0] octane-2,4,6,8- tetracarboxylic acid, Although there exists a tendency to reduce liquid-crystal orientation, there exists an effect which improves a voltage holding characteristic. Therefore, when importance is placed on voltage retention, the structural unit represented by formula (7) wherein Y is a polyimide precursor having a structural unit represented by formula (7) which is only these tetravalent organic groups, or Y is a tetravalent organic group; It is preferable to set it as the polyimide precursor which has a structural unit represented by Formula (7) whose Y is a tetravalent organic group other than these tetravalent organic groups.

The method of obtaining the polyimide precursor which has a structural unit represented by Formula (7) is not specifically limited. Usually, in the reaction of the tetracarboxylic dianhydride component containing tetracarboxylic dianhydride for forming Y of Formula (7), and the diamine component containing diamine for forming X of Formula (7), Can be obtained by

Moreover, when obtaining the polyimide precursor in which several types of Y are mixed by a specific ratio, or when obtaining the polyimide precursor in which several types of X are mixed by a specific ratio, the tetracarboxylic dianhydride for composing Y and What is necessary is just to react, using the diamine for composing X respectively by the target mixture ratio. For example, in order to make the ratio of X which has a specific structure in a polyimide precursor into 10 mol%, the diamine for composing X which has a specific structure in the diamine component whole quantity used for the synthesis | combination of a polyimide precursor is used. What is necessary is just to make a ratio 10 mol%. Similarly, in order to make the ratio of Y which has an aromatic structure in a polyimide precursor into 20 mol%, Y which has an aromatic structure in the tetracarboxylic dianhydride component whole quantity used for the synthesis | combination of a polyimide precursor is comprised. What is necessary is just to make the ratio of tetracarboxylic dianhydride to be 20 mol%.

Although the specific example of the diamine for forming X of Formula (7) is shown below, it is not limited to these.

As the diamine for forming X having the formula (8) in the structure, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1, 7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, and the like. Moreover, 1, 3-bis (4-aminophenyl) propane, 1, 4-bis (diamine) which is a diamine corresponding to Formula (11) as a diamine which comprises Formula (8) and X which has an aromatic ring in a structure. 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) nonane, 1,10-bis (4-aminophenyl) decane and the like. Similarly, 1,3-bis (4-aminophenoxy) propane, 1,4-bis (4-aminophenoxy) butane, 1,5-bis (4-amino which is a diamine corresponding to formula (12) Phenoxy) pentane, 1,6-bis (4-aminophenoxy) hexane, 1,7-bis (4-aminophenoxy) heptane, 1,8-bis (4-aminophenoxy) octane, 1,9 -Bis (4-aminophenoxy) nonane, 1, 10-bis (4-aminophenoxy) decane, etc. are mentioned. Similarly, as a diamine corresponding to Formula (13), di (4-aminophenyl) propane-1,3-dioate, di (4-aminophenyl) butane-1,4-dioate, di (4-aminophenyl ) Pentane-1,5-dioate, di (4-aminophenyl) hexane-1,6-dioate, di (4-aminophenyl) heptan-1,7-dioate, di (4-aminophenyl) octane -1,8-dioate, di (4-aminophenyl) nonane-1,9-dioate, di (4-aminophenyl) decane-1,10-dioate, and the like. Similarly, as a diamine corresponding to Formula (14), 1,3-bis [4- (4-aminophenoxy) phenoxy] propane, 1,4-bis [4- (4-aminophenoxy) phenoxy] Butane, 1,5-bis [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.

As a diamine for forming X which has Formula (9) in a structure, 1, 3-bis (4-amino phenoxy) benzene, 1, 4-bis (4-amino phenoxy) benzene, 1, 3-bis [ 4- (4-aminophenoxy) phenoxy] benzene, 1,4-bis [4- (4-aminophenoxy) phenoxy] benzene, etc. are mentioned.

As a diamine for forming X which has Formula (10) in a structure, 4,4'- diaminobenzidine, 4,4'- diamino- p-terphenyl, etc. are mentioned.

As a diamine for making X into paraphenylene, 1, 4- diamino benzene is mentioned.

The diamine illustrated in the said specific example is preferable as a raw material for synthesize | combining a specific polymer (B), and among these diamine components used for reaction with the tetracarboxylic dianhydride component, Preferably it is 10-100 mol. %, More preferably, the polyimide precursor which has a structural unit represented by Formula (7) synthesize | combined using 50-100 mol% is preferable as a specific polymer (B).

In addition, although the specific example of the diamine for composing X other than the bivalent organic group or paraphenylene group which has either of formula (8)-(10) in a structure is shown below, it is not limited to these.

Examples of the alicyclic diamine include 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, 4,4'-diaminodicyclohexylmethane, 4,4'-diamino-3,3'- Dimethyl dicyclohexylamine, isophorone diamine, etc. are mentioned.

Examples of carbocyclic aromatic diamines include o-phenylenediamine, m-phenylenediamine, 2,4-diaminotoluene, 1,3-diamino-4-chlorobenzene, 4,4'-diaminodiphenyl -2,2'-propane, 4,4'-diaminodiphenylmethane, 2,2'-diaminostilbene, 4,4'-diaminostilbene, 4,4'-diaminodiphenylether, 4,4'-diphenylthioether, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 4,4'-diaminobenzoic acid phenyl ester, 2,2'-diamino Benzophenone, 4,4'-diaminobenzyl, bis (4-aminophenyl) phosphine oxide, bis (3-aminophenyl) methylsulpin oxide, bis (4-aminophenyl) phenylphosphine oxide, bis (4- Aminophenyl) cyclohexylphosphine oxide, 1,8-diaminonaphthalene, 1,5-diaminonaphthalene, 1,5-diaminoanthraquinone, diaminofluorene, bis (4-aminophenyl) diethylsilane, Bis (4-aminophenyl) dimethylsilane, bis (4-aminophenyl) tetramethyldisiloxane , 3,4'-diaminodiphenyl ether, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, bis [4- (4-aminophenoxy) phenyl] sulfone, 2,2- Bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene and the like. .

Examples of diamines containing nitrogen atoms in addition to two amino groups include 2,4-diaminodiphenylamine, 2,4-diaminopyridine, 2,4-diamino-s-triazine, 2,7-diamino Dibenzofuran, 3,7-diaminophenothiazine, 2,5-diamino-1,3,4-thiadiazole, 2,4-diamino-6-phenyl-s-triazine, N, N '-Bis (4-aminophenyl) -N-phenylamine, N, N'-bis (4-aminephenyl) -N-methylamine, 4,4'-diaminodiphenylurea and the like.

As diamine for raising the pretilt angle of a liquid crystal, 1-dodecyloxy-2,4-diaminobenzene, 1-hexadecyloxy-2,4-diaminobenzene, 1-octadecyloxy-2,4 -Diaminobenzene, 1,1-bis (4-aminophenyl) cyclohexane, 2,2-bis [4- (4-aminophenoxy) phenyl] octane, 4,4'-diamino-3-dodecyldi Phenylether, 4- (4-trans-n-heptylcyclohexylphenoxy) -1,3-diaminobenzene, 4- (4-trans-n-pentylcyclohexylphenoxy) -1,3-diaminobenzene And 4-trans-n-pentylbicyclohexyl-3,5-diaminobenzoate and the like.

When R in General formula (7) is an alkyl group, alcohol, such as methanol, ethanol, 1-propanol, and 2-propanol, and tetracarboxylic dianhydride are made to react, and it is made into tetracarboxylic-acid diester, and diamine and dehydration condensation are carried out. Or it can obtain by dehydrating condensation of alcohol and a polyamic acid.

When a specific polymer (A) or a specific polymer (B) is obtained by reaction of a tetracarboxylic dianhydride component and a diamine component as mentioned above, a tetracarboxylic dianhydride component and a diamine component in an organic solvent. The method of mixing and reacting to obtain a polyamic acid is simple. And polyamic acid ester can be obtained by the method of converting the carboxyl group of a polyamic acid to ester.

The organic solvent to be used in the reaction is not particularly limited as long as the produced polyamic acid or polyamic acid ester is dissolved. Specific examples thereof include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, dimethyl sulfoxide, tetramethylurea, pyridine, dimethyl sulfone, hexamethyl sulfoxide, (gamma) -butyrolactone, etc. are mentioned. These may be used singly or in combination. Moreover, even if it is a solvent which does not melt a polyamic acid or polyamic acid ester, you may mix and use with the said solvent in the range which does not precipitate the produced polyamic acid or polyamic acid ester. In addition, since water in the organic solvent inhibits the polymerization reaction and further causes hydrolysis of the produced polyamic acid or polyamic acid ester, it is preferable to use an organic solvent that is dehydrated and dried as much as possible.

As a method of mixing a tetracarboxylic dianhydride component and a diamine component in an organic solvent, the solution which disperse | distributed or dissolved the diamine component in the organic solvent is stirred, and the tetracarboxylic dianhydride component is disperse | distributed as it is or in an organic solvent. Or a method of dissolving, adding a diamine component to a solution in which the tetracarboxylic dianhydride component is dispersed or dissolved in an organic solvent, a method of alternately adding a tetracarboxylic dianhydride component and a diamine component, or the like. These may be mentioned and any method of these may be sufficient in this invention. Moreover, when a tetracarboxylic dianhydride component or a diamine component consists of multiple types of compounds, you may make it react in the state which mixed these multiple types of components previously, and may make them react individually one by one.

The temperature at the time of making a tetracarboxylic dianhydride component and a diamine component react in an organic solvent is 0-150 degreeC normally, Preferably it is 5-100 degreeC, More preferably, it is 10-80 degreeC. The higher the temperature, the earlier the polymerization reaction is terminated, but when the temperature is too high, a high molecular weight polymer (polyamic acid or polyimide ester) may not be obtained. In addition, although the reaction can be carried out at an arbitrary concentration, if the concentration is too low, it is difficult to obtain a high molecular weight polymer, and if the concentration is too high, the viscosity of the reaction solution becomes too high and uniform stirring becomes difficult. Is 1 to 50% by weight, more preferably 5 to 30% by weight. The reaction initial stage may be performed in high concentration | density, and may add an organic solvent after that.

It is preferable that the ratio of the tetracarboxylic dianhydride component and diamine component used for the polymerization reaction of polyamic acid and polyamic acid ester is 1: 0.8-1.2 in molar ratio. Moreover, since the coloring of a solution may become large for the polyamic acid and polyamic acid ester obtained by making the diamine component excess, what is necessary is just to set it as 1: 0.8-1 when a coloring of a solution is anxious. As with the normal polycondensation reaction, the closer the molar ratio is to 1: 1, the larger the molecular weight of the polyamic acid or polyamic acid ester obtained. If the molecular weight of a polyamic acid or polyamic acid ester is too small, the intensity | strength of the coating film obtained there may become inadequate, On the contrary, if the molecular weight of a polyamic acid or polyamic acid ester is too large, the viscosity of the liquid crystal aligning agent manufactured there will be too high It becomes high and the workability at the time of coating film formation, and the uniformity of a coating film may worsen. Therefore, as for the polyamic acid and polyamic acid ester used for the liquid crystal aligning agent of this invention, 0.1-2.0 are preferable at reduced viscosity (concentration 0.5dl / g, 30 degreeC in NMP), More preferably, it is 0.2-1.5.

When it is not desired to contain the solvent used for the polymerization of polyamic acid or polyamic acid ester in the liquid crystal aligning agent of this invention, or when an unreacted monomer component or an impurity exists in a reaction solution, this precipitation collection and purification are performed. . In the method, it is preferable to throw a solution of a polyamic acid and a polyamic acid ester into the stirring poor solvent, and to collect and collect. The poor solvent used for precipitation recovery of polyamic acid or polyamic acid ester is not particularly limited, but methanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, etc. It can be illustrated. The polyamic acid and the polyamic acid ester precipitated by pouring into the poor solvent can be collected by filtration and washing, recovered, and subjected to normal temperature or heat drying under normal pressure or reduced pressure to obtain a powder. When this powder is further melt | dissolved in a good solvent, and the operation to reprecipitate is repeated 2-10 times, a polyamic acid and polyamic acid ester can also be refine | purified. When all impurities cannot be removed by one precipitation recovery operation, it is preferable to perform this purification step. As the poor solvent at this time, it is preferable to use three or more types of poor solvents such as alcohols, ketones, and hydrocarbons because the efficiency of purification is further increased.

As above-mentioned, the liquid crystal aligning agent of this invention contains the said specific polymer (A) and a specific polymer (B). Thus, by setting it as the liquid crystal aligning agent containing a specific polymer (A) and a specific polymer (B), it is excellent in liquid crystal orientation, rubbing tolerance, voltage retention characteristic, and charge accumulation characteristic, there is little ionic impurity amount, high transmittance | permeability, and light The liquid crystal aligning film with small change of the volume resistivity by is obtained.

Although it is not necessarily clear why the said effect arises by the structure of this invention, the following are generally considered. As for the polyamic acid obtained using the anhydride of tetracarboxylic acid represented by Formula (1), imidation by heat does not advance easily. Therefore, it is thought that many carboxyl groups remain in the liquid crystal aligning film manufactured by apply | coating and baking the liquid crystal aligning agent of this invention containing a specific polymer (A) component. By this carboxyl group interacting with the nitrogen atom derived from the diamine compound represented by Formula (5) and Formula (6), the movement of the incident electron on the nitrogen atom by light is suppressed, As a result, by the light of a liquid crystal aligning film It is considered that the change in volume resistivity is suppressed. Moreover, it is thought that the volume resistivity itself could also be lowered by interaction of this carboxyl group and a nitrogen atom.

And liquid crystal aligning property, rubbing tolerance, voltage retention by making this specific polymer (A) into the liquid crystal aligning agent contained with the specific polymer (B) which is a polyimide precursor which has a structural unit represented by Formula (7) which is excellent in liquid crystal alignability. A liquid crystal aligning film is obtained which is excellent in characteristics and charge accumulation characteristics, has a small amount of ionic impurities, high transmittance, and small change in volume resistivity due to light.

Although the form of the liquid crystal aligning agent of this invention demonstrated below is a coating liquid containing a specific polymer (A) and a specific polymer (B), if the uniform thin film can be formed on a board | substrate, the liquid crystal aligning of this invention The agent may be in other forms.

In order to make it the coating liquid containing a specific polymer (A) and a specific polymer (B), you may mix the reaction solution of a polyamic acid and a polyamic acid ester as it is, and after melt | dissolving solid polyamic acid and polyamic acid ester in an organic solvent You may mix.

The organic solvent is not particularly limited as long as it dissolves the polymer (polyamic acid or polyimide ester) to be contained. Examples thereof include N, N-dimethylformamide, N, N-dimethylacetamide, and N. -Methyl-2-pyrrolidone, N-methylcaprolactam, 2-pyrrolidone, N-ethylpyrrolidone, N-vinylpyrrolidone, dimethyl sulfoxide, tetramethylurea, pyridine, dimethyl sulfone, hexa Methyl sulfoxide, (gamma) -butyrolactone, etc. are mentioned, These may be one type, and may mix and use multiple types.

Moreover, even if it is a solvent which does not melt a polymer independently, as long as it is a range in which a polymer does not precipitate, it can mix with the liquid crystal aligning agent of this invention. In particular, ethyl cellosolve, butyl cellosolve, ethyl carbitol, butyl carbitol, ethyl carbitol acetate, ethylene glycol, 1-methoxy-2-propanol, 1-ethoxy-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, Solvents having low surface tension such as dipropylene glycol, 2- (2-ethoxypropoxy) propanol, lactic acid methyl ester, lactic acid ethyl ester, lactic acid n-propyl ester, lactic acid n-butyl ester and lactic acid isoamyl ester It is known that coating film uniformity improves at the time of application | coating to a board | substrate by mixing suitably, It is used preferably also in the liquid crystal aligning agent of this invention.

Although the liquid crystal aligning agent of this invention can change solid content concentration suitably according to the setting of the thickness of the liquid crystal aligning film to form, it is preferable to make solid content concentration into 1 to 10 weight%. If it is less than 1 weight%, it will become difficult to form a uniform and defect-free coating film, and when more than 10 weight%, the storage stability of a solution may worsen.

In addition, in order to improve the adhesiveness of the coating film to a board | substrate, you may add additives, such as a silane coupling agent, to the liquid crystal aligning agent of this invention, and also other polymers other than a specific polymer (A) and a specific polymer (B) You may add.

After filtering as needed, the liquid crystal aligning agent of this invention obtained as mentioned above can be apply | coated to a board | substrate, it can be made to dry and bake to make a coating film, and this coating film surface is subjected to the orientation processing, such as rubbing or light irradiation, It can be used as a liquid crystal aligning film even if it does not or orientation treatment.

In this case, the substrate to be used is not particularly limited as long as it is a substrate having high transparency, and plastic substrates such as glass substrates, acrylic substrates and polycarbonate substrates can be used, and ITO (Indium Tin Oxide) electrodes for liquid crystal driving, It is preferable to use the formed substrate in view of the simplification of the process. In the reflective liquid crystal display element, only an opaque one such as a silicon wafer can be used as long as it is a substrate on one side, and in this case, a material that reflects light such as aluminum can be used.

As a coating method of a liquid crystal aligning agent, the spin coat method, the printing method, the inkjet method, etc. are mentioned, The transfer printing method is widely used industrially from a productivity viewpoint, and it is used suitably also in the liquid crystal aligning agent of this invention. do.

Although the drying process after apply | coating a liquid crystal aligning agent is not necessarily required, when the time from application | coating to baking is not constant for every board | substrate, or is not immediately baked after application | coating, it is preferable to include a drying process. The solvent should just be evaporated to such an extent that a coating film shape does not deform | transform by conveyance of a board | substrate etc., and this drying is not specifically limited about the drying means. For example, the method of drying for 0.5 to 30 minutes, Preferably 1 to 5 minutes is taken on 50-150 degreeC, Preferably it is 80-120 degreeC hotplate.

Although baking after apply | coating a liquid crystal aligning agent and drying as needed can be performed at arbitrary temperature of 100-350 degreeC, Preferably it is 150 degreeC-300 degreeC, More preferably, it is 200 degreeC-250 degreeC. When polyamic acid is contained in a liquid crystal aligning agent, although the conversion ratio from a polyamic acid to a polyimide changes with this baking temperature, it is not necessary to always imidize the liquid crystal aligning agent of this invention. However, it is preferable to bake at 10 degreeC or more higher temperature than heat processing temperature, such as sealing compound hardening, which is needed in a liquid crystal cell manufacturing process.

When the thickness of the coating film after baking is too thick, it becomes disadvantageous in terms of power consumption of a liquid crystal display element, and when too thin, the reliability of a liquid crystal display element may fall, It is 5-300 nm, Preferably it is 10-100 nm. .

Since the liquid crystal aligning film obtained from the liquid crystal aligning agent of this invention as mentioned above has the outstanding characteristic, liquid crystal display elements, such as TN (Twisted Nematic), STN (Super Twisted Nematic), TFT, a transverse electric field type, and also ferroelectricity, It can be used as a liquid crystal aligning film for antiferroelectric liquid crystal display elements. In particular, it can use suitably as a liquid crystal aligning film for liquid crystal display elements of the transverse electric field type which an afterimage derived from liquid crystal aligning property tends to occur.

After obtaining the board | substrate with which the liquid crystal aligning film was formed from the liquid crystal aligning agent of this invention by said method, the liquid crystal display element of this invention manufactures a liquid crystal cell by a well-known method, and makes it a liquid crystal display element. For example of liquid crystal cell manufacture, a pair of substrates on which a liquid crystal alignment film is formed is sandwiched between spacers of 1 to 30 µm, preferably 2 to 10 µm, so that the rubbing direction becomes an arbitrary angle of 0 to 270 °. It is common to install and fix the circumference | surroundings with a sealing compound, and to inject and seal a liquid crystal. There is no restriction | limiting in particular about a liquid crystal sealing method, The vacuum method which injects a liquid crystal after making the inside of the manufactured liquid crystal cell into pressure reduction, the dropping method etc. which perform sealing after dripping a liquid crystal can be illustrated.

In this way, since the liquid crystal display element manufactured using the liquid crystal aligning agent of this invention is excellent in liquid crystal aligning property, and has the outstanding electrical property, it can be set as the liquid crystal display device in which contrast fall and afterimage hardly occur, It is used suitably for the liquid crystal display element by various systems using nematic liquid crystals, such as liquid crystal display elements, such as TN, STN, TFT, and a transverse electric field type. Moreover, by selecting the liquid crystal to be used, it can be used also for a ferroelectric and antiferroelectric liquid crystal display element. Among these liquid crystal display elements, it is particularly preferably used for a transverse electric field type liquid crystal display element which is likely to cause residual images derived from liquid crystal alignment properties.

Example

Although an Example is given to the following and this invention is demonstrated in more detail, this invention is not limited to these. The abbreviation used by the following example and a comparative example is as follows.

DA-1: 4,4'-diaminodiphenylamine

DA-2: 4,4'-diaminodiphenylmethane

DA-3: 1,5-bis (4-aminophenoxy) pentane

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

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

CA-3: Pyromellitic Acid 2 Anhydride

CA-4: 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic acid dianhydride

[Synthesis Example 1]

7.97 g (40.0 mmol) of DA-1 and 1.98 g (10.0 mmol) of DA-2 were placed in a 200 mL four-necked flask with a stirring apparatus and a nitrogen inlet tube, and N-methyl-2-pyrroli 72.34 g of money was added and dissolved by stirring while sending nitrogen. 6.86 g (35.0 mmol) was added for CA-1, stirring this diamine solution, and it stirred at water temperature for 30 minutes. Thereafter, 3.13 g (12.5 mmol) of CA-2 was added while stirring the solution, and N-methyl-2-pyrrolidone was further added so that the solid content concentration was 20% by mass, and the oil bath was added under a nitrogen atmosphere. It stirred at 50 degreeC for 3 hours. Furthermore, N-methyl-2-pyrrolidone was further added so that solid content concentration might be 11 mass%, and it stirred overnight at 50 degreeC using an oil bath in nitrogen atmosphere, and obtained the solution of polyamic acid. It was 191 mPa * s when the viscosity at 25 degrees C of this polyamic-acid solution was confirmed with the E-type viscosity meter (made by Torquay Industries).

2.20 g of N-methyl-2-pyrrolidone solution containing 5.3 g of N-methyl-2-pyrrolidone and 1.0% by weight of 3-aminopropyltriethoxysilane in 20.0 g of this polyamic acid solution, and butyl cell 9.17g of rosolves were added, and the polyamic-acid solution (A1) whose solid content concentration was 6.0 mass% was obtained.

[Synthesis Example 2]

7.49 g (37.6 mmol) of DA-1 and 1.86 g (9.4 mmol) of DA-2 were added to a 300 ml four-necked flask with a stirring apparatus and a nitrogen inlet tube, and N-methyl-2-pyrroli 72.08 g of Don was added and dissolved by stirring while sending nitrogen. CA-1 was added 2.12g (10.8 mmol), stirring this diamine solution, and it stirred at water temperature for 30 minutes. Thereafter, 8.82 g (35.3 mmol) of CA-2 was added while stirring the solution, and N-methyl-2-pyrrolidone was further added so that the solid content concentration was 20% by mass, and the oil bath was added under a nitrogen atmosphere. It stirred at 50 degreeC for 3 hours. Furthermore, N-methyl-2-pyrrolidone was further added so that solid content concentration might be 11 mass%, and it stirred overnight at 50 degreeC using an oil bath in nitrogen atmosphere, and obtained the solution of polyamic acid. It was 207 mPa * s when the viscosity at 25 degrees C of this polyamic-acid solution was confirmed with the E-type viscosity meter (made by Torquay Industries, Ltd.).

2.20 g of N-methyl-2-pyrrolidone solution containing 6.25 g of N-methyl-2-pyrrolidone and 1.0% by weight of 3-aminopropyltriethoxysilane in 20.0 g of this polyamic acid solution, and butyl cell 9.48g of rosolves were added, and the polyamic-acid solution (A2) whose solid content concentration is 5.8 mass% was obtained.

[Synthesis Example 3]

8.93 g (44.8 mmol) of DA-1 and 2.22 g (11.2 mmol) of DA-2 were added to a 300 ml four-necked flask with a stirring apparatus and a nitrogen inlet tube, and N-methyl-2-pyrroli 108.54 g of Don was added and dissolved by stirring while sending nitrogen. 13.52 g (54.0 mmol) addition of CA-2 is carried out stirring this diamine solution, N-methyl- 2-pyrrolidone is further added so that solid content concentration may be 12 mass%, and it uses an oil bath under nitrogen atmosphere. It stirred at 50 degreeC overnight, and obtained the solution of polyamic acid. It was 153 mPa * s when the viscosity at 25 degrees C of this polyamic-acid solution was confirmed with the E-type viscosity meter (made by Torquay Industries, Ltd.).

2.32 g of N-methyl-2-pyrrolidone solution containing 10.92 g of N-methyl-2-pyrrolidone and 1.0% by weight of 3-aminopropyltriethoxysilane in 16.8 g of this polyamic acid solution, and butyl cell 10.01 g of Rosolve was added, and the solid content concentration obtained the polyamic-acid solution (A3) of 5.8 mass%.

[Synthesis Example 4]

80.0 g and 3.83 g (28 mmol) of DA-1 were added to a 100 ml four-necked flask equipped with a stirring device and a nitrogen inlet tube, and stirred while sending nitrogen. It was dissolved. CA-1 was added 3.30g (17 mmol), stirring this diamine solution, and it stirred at 10-15 degreeC for 2.5 hours. Thereafter, 0.95 g (4.8 mmol) of DA-2 was added and stirred at 10 to 15 ° C. for 0.5 hour, then 1.44 g (4.8 mmol) of CA-4 was added thereto, followed by stirring at 20 to 25 ° C. for 5 hours. A solution of polyamic acid was obtained. It was 168 mPa * s when the viscosity at 25 degrees C of this polyamic-acid solution was confirmed with the E-type viscosity meter (made by Torquay Industries, Ltd.).

5.0 g of 3-phenyl N-methyl-2-pyrrolidone solution containing 1.66 g of N-methyl-2-pyrrolidone and 1.0% by weight of 3-aminopropyltriethoxysilane in 50.0 g of this polyamic acid solution 10 g of N-methyl-2-pyrrolidone solution containing 5.0% by weight of aminopropyltrimethoxysilane and 16.67 g of butyl cellosolve were added to obtain a polyamic acid solution (A4) having a solid content concentration of 6.0% by mass. .

[Synthesis Example 5]

6.87 g (24 mmol) of DA-3 and 80.0 g of N-methyl-2-pyrrolidone were added to a 100 ml four-necked flask with a stirring device and a nitrogen inlet tube, and stirred while sending nitrogen. Dissolved. 5.03 g (23 mmol) was added for CA-3, stirring this diamine solution, N-methyl- 2-pyrrolidone was added so that solid content concentration might be 12 mass%, and it used the oil bath overnight at 50 degreeC. It stirred and obtained the solution of polyamic acid. It was 525 mPa * s when the viscosity at 25 degrees C of this polyamic-acid solution was confirmed with the E-type viscosity meter (made by Torquay Industries).

12 g of N-methyl-2-pyrrolidone solution containing 18 g of N-methyl-2-pyrrolidone and 5.0 weight% of 3-phenylaminopropyltrimethoxysilane in 50 g of this polyamic acid solution, and butyl 20 g of cellosolves were added to obtain a polyamic acid solution (B1) having a solid content concentration of 6.0% by mass.

Example 1

The polyamic-acid solution (A1) and polyamic-acid solution (B1) obtained by the synthesis example were mixed so that it might become (A1) / (B1) = 80/20 by weight ratio, and the liquid crystal aligning agent (C1) of this invention was obtained.

[Example 2]

The polyamic-acid solution (A2) and polyamic-acid solution (B1) obtained by the synthesis example were mixed so that it might become (A2) / (B1) = 80/20 by weight ratio, and the liquid crystal aligning agent (C2) of this invention was obtained.

[Example 3]

The polyamic-acid solution (A3) and polyamic-acid solution (B1) obtained by the synthesis example were mixed so that it might become (A3) / (B1) = 80/20 by weight ratio, and the liquid crystal aligning agent (C3) of this invention was obtained.

Comparative Example 1

The polyamic-acid solution (A4) and polyamic-acid solution (B1) obtained by the synthesis example were mixed so that it might become (A4) / (B1) = 80/20 by weight ratio, and the liquid crystal aligning agent (C4) of this invention was obtained.

Using the liquid crystal aligning agent obtained in Example 1, Example 2, Example 3, and Comparative Example 1, an evaluation sample was produced, respectively, and liquid crystal alignability, volume resistivity, voltage retention, ion density, and transmittance were measured. Measured. The obtained result is shown to Tables 1-3.

&Lt; Production of liquid crystal cell &

After filtering the obtained liquid crystal aligning agent with a 1.0 micrometer filter, spin-coating on the glass substrate with a transparent electrode, drying for 2 minutes on a 70 degreeC hotplate, baking at 230 degreeC for 15 minutes, and having a film thickness of 100 nm A coating film was obtained. After rubbing this polyimide membrane with a rayon cloth (roll diameter 120mm, rotation speed 1000rpm, moving speed 20mm / sec, indentation amount 0.4mm), ultrasonic irradiation is performed in pure water for 1 minute, and it dried at 80 degreeC for 10 minutes. I was. In addition, in Examples 1-3 and Comparative Example 1, the rubbing treatment was excellent in rubbing resistance without occurrence of scratches or dust due to shaving of the film and peeling of the film. After preparing two board | substrates with such a liquid crystal aligning film, providing a 4 micrometer spacer on the liquid crystal aligning film surface of one board | substrate, combining so that the rubbing direction of two board | substrates may become antiparallel, and sealing around the liquid crystal injection hole Then, an empty cell having a cell gap of 4 µm was prepared. A liquid crystal (MLC-2041, manufactured by Merck Co., Ltd.) was vacuum-injected into this cell at room temperature, and the injection port was sealed to obtain an antiparallel liquid crystal cell.

The orientation state of this liquid crystal cell was observed with the polarization microscope, and the thing with "good" and the orientation defect which did not have an orientation defect was made into "defect".

After filtering the obtained liquid crystal aligning agent with the filter of 0.2 micrometer, it spin-coated on the glass substrate with an ITO transparent electrode, dried for 5 minutes on a hotplate of 80 degreeC, and baked at 220 degreeC for 20 minutes, and film thickness A 220 nm coating film (liquid crystal aligning film) is formed. Aluminum was deposited on the surface of this coating film via a mask, the upper electrode (aluminum electrode) of 1.0 mm (phi) was formed, and it was set as the sample for volume resistivity measurement. A voltage of 10 V was applied between the ITO electrode and the aluminum electrode of this sample, the current value after 180 seconds from the voltage application was measured, and the volume resistivity was calculated from the measured value of this value, the electrode area and the film thickness. Moreover, the backlight of LED was provided under the sample board | substrate, and it measured respectively under lighting and unlit, and measured the change of the volume resistivity by light. When the value at the time of LED extinction was divided by the value at the time of LED lighting, it was set as "(circle)", and when it was 2.0-3.0, it was "(circle)", and it was set as "x" other than it.

The measurement was performed using the 6254 type liquid crystal physical property evaluation apparatus by the Toyo Technica company, using the liquid crystal cell manufactured similarly to said <production of a liquid crystal cell>. A voltage of 1 V, an application time of 60 μsec., And an interval of 100 msec. 100 msec. The voltage retention after (voltage of 100 msec. Immediately after application / voltage 100% after application | release) was measured. In the measurement, the temperature of the liquid crystal cell was measured at 23 degreeC and 100 degreeC.

The measurement was performed using the 6254 type liquid crystal physical property evaluation apparatus by the Toyo Technica company, using the liquid crystal cell manufactured similarly to said <production of a liquid crystal cell>. The measurement applied 10V and 0.01 Hz triangle wave, computed the area corresponded to the ion density of the obtained waveform, and set it as the ion density. In the measurement, the temperature of the liquid crystal cell was measured at 23 degreeC and 60 degreeC.

The liquid crystal aligning agent was filtered with the 1.0 micrometer filter, spin-coated on the quartz substrate, dried for 2 minutes on the 70 degreeC hotplate, and baked at 230 degreeC for 15 minutes, and obtained the coating film of 100 nm in film thickness. Using this sample, it measured using the UV-3100PC magnetic spectrophotometer by Shimadzu Corporation.

As a result, by using the liquid crystal aligning agent of this invention, it is excellent in liquid crystal orientation, rubbing tolerance, high voltage retention characteristic, charge accumulation is reduced, ion density is low, transmittance is high, and the volume resistivity by light It was confirmed that the liquid crystal aligning film with a small change of was obtained. Moreover, since the liquid crystal display element which has the liquid crystal aligning film obtained from the liquid crystal aligning agent of this invention is excellent in liquid crystal aligning property, and has the outstanding electrical property, it will be set as the liquid crystal display device which display defect, a fall of contrast, and an afterimage hardly occur. Can be.

Claims

Liquid crystal aligning agent containing following specific polymer (A) and specific polymer (B).
Specific polymer (A): At least 1 of the tetracarboxylic dianhydride component containing the dianhydride of tetracarboxylic acid represented by following formula (1), and the diamine compound represented by following formula (5) and (6) Polyamic acid obtained by making the diamine component containing react.
[Chemical Formula 1]

(2)

(In Formula (5) and (6), one or more of arbitrary hydrogen atoms on a benzene ring may be substituted by monovalent organic groups other than a primary amino group.)
Specific polymer (B): The polyimide precursor which has a structural unit represented by following formula (7).
(3)

(In formula (7), R represents a hydrogen atom or an alkyl group, Y represents a tetravalent organic group, X represents a divalent organic group, and 10-100 mol% of X is a following formula (8)-(10) It is a divalent organic group or paraphenylene group which has either in a structure.)
[Chemical Formula 4]

(M <_1> is an integer of 2-18 in a formula (8).)
[Chemical Formula 5]

(In Formula (9), one or more of arbitrary hydrogen atoms on a benzene ring may be substituted by monovalent organic groups other than a primary amino group, and m <_2> is an integer of 1-8.)
[Chemical Formula 6]

The method of claim 1,
The tetracarboxylic dianhydride component in a specific polymer (A) selects from the anhydride of tetracarboxylic acid represented by following formula (1), and the tetracarboxylic acid represented by following formula (2)-(4). The liquid crystal aligning agent which consists of dihydride of at least 1 sort (s) of compound which becomes.
(7)

3. The method of claim 2,
The tetracarboxylic dianhydride component in a specific polymer (A) is represented by 10-100 mol% of dianhydride of tetracarboxylic acid represented by Formula (1), and the tetracarboxyl represented by Formula (2)-(4) The liquid crystal aligning agent which consists of 0-90 mol% of dihydrides of at least 1 sort (s) of compound chosen from an acid.

The method of claim 3, wherein
The tetracarboxylic dianhydride component in a specific polymer (A) is chosen from 10-100 mol% of dianhydride of tetracarboxylic acid represented by Formula (1), and the tetracarboxylic acid represented by Formula (3). The liquid crystal aligning agent which consists of 0-90 mol% of dihydrides of at least 1 type of compound.

5. The method according to any one of claims 1 to 4,
The liquid crystal aligning agent whose 20-100 mol% of Y of Formula (7) is a tetravalent organic group which has an aromatic structure.

The liquid crystal aligning film obtained using the liquid crystal aligning agent in any one of Claims 1-5.

The liquid crystal display element provided with the liquid crystal aligning film of Claim 6.