JP5590304B2 - Liquid crystal aligning agent and liquid crystal display element - Google Patents

Description

  The present invention relates to a liquid crystal aligning agent, a liquid crystal alignment film, and a liquid crystal display element. More specifically, when the film quality is uniform, a liquid crystal alignment film with excellent electrical properties and heat resistance can be given, and also a liquid crystal alignment agent with excellent coating properties and high-quality display, and when driven for a long time The present invention relates to a liquid crystal display element in which deterioration of display quality is suppressed.

Currently known liquid crystal display elements can be classified into the following modes based on the electrode structure and the physical properties of the liquid crystal molecules used.
First, a liquid crystal alignment film is formed on the surface of a substrate on which a transparent conductive film is provided to form a substrate for a liquid crystal display element, and two of them are arranged opposite to each other and nematic liquid crystal having positive dielectric anisotropy in the gap is formed. A TN having a so-called TN type (twisted nematic) liquid crystal cell in which the long axis of the liquid crystal molecules is continuously twisted by 90 ° from one substrate to the other substrate by forming layers into a sandwich cell. 2. Description of the Related Art An STN (Super Twisted Nematic) type liquid crystal display element (Patent Document 2) capable of realizing a higher duty ratio than a TN type liquid crystal display element (Patent Document 1) and a TN type liquid crystal display element is known. Further, a counter electrode arrangement similar to that of the TN type liquid crystal display element is adopted, but a nematic liquid crystal layer having a negative dielectric anisotropy is injected into the electrode gap to align the liquid crystal substantially perpendicularly to the substrate. A Vertical Alignment) type display element is known (Patent Document 3). This VA type display element has a high contrast and can produce a large area display element.
On the other hand, an IPS (In-Plane Switching) type liquid crystal display element in which the driving direction of the liquid crystal when an electric field is applied is only in the in-plane direction of the substrate by arranging the electrode pairs in a comb-like shape on the surface of one substrate (patented) Document 4), an FFS (Fringe Field Switching) type liquid crystal display element (Patent Document 5) in which the luminance is improved by changing the IPS type electrode structure and increasing the aperture ratio of the display element portion is known, Excellent viewing angle characteristics.
In addition to these, an OCB (Optical Compensated Bend) type liquid crystal display element (Patent Document 6) that has low viewing angle dependency and excellent high-speed response of a video screen has been developed.

As materials for the liquid crystal alignment film in these liquid crystal display elements, resin materials such as polyamic acid, polyimide, polyamide, and polyester are known, and in particular, a liquid crystal alignment film made of polyamic acid or polyimide has heat resistance, mechanical strength, It has excellent affinity with liquid crystals and is used in many liquid crystal display elements (Patent Documents 7 to 8).
In recent years, liquid crystal display devices have been developed for television applications, and coupled with the development of finer display and advanced video fixing technology, viewing is impossible for a long time compared to conventional liquid crystal display devices. Has become normal. However, it has been pointed out that image quality deteriorates when a liquid crystal display element having a liquid crystal alignment film made of a conventionally known material is driven for a long time. This phenomenon is considered to be caused by the fact that the thermal stress is applied to the liquid crystal alignment film when continuously driven for a long time, and as a result, the electrical characteristics of the liquid crystal alignment film, particularly the voltage holding ratio, is significantly reduced. It is desired to provide a liquid crystal alignment film material that does not cause such deterioration.
Furthermore, liquid crystal televisions tend to have larger screens, and substrates used for liquid crystal display elements tend to increase year by year from the viewpoint of reducing manufacturing costs. Therefore, after applying the liquid crystal aligning agent to the substrate, the time until it is baked (retention time) tends to be longer. When using a conventionally known liquid crystal aligning agent, it is pointed out that the uniformity of the coating film is impaired or the pinhole is generated when the holding time is prolonged, and the display quality of the obtained liquid crystal display element is deteriorated. It has been desired to provide a liquid crystal aligning agent that can form a uniform coating film even if it is left for a long time and can provide a liquid crystal display element excellent in display quality.

Japanese Patent Laid-Open No. 04-153622 JP 60-107020 A Japanese Patent Laid-Open No. 11-258605 JP 56-91277 A JP 2008-216572 A JP 2009-48211A US Pat. No. 5,928,733 Japanese Patent Laid-Open No. 62-165628

The present invention has been made in view of the above circumstances, and the object thereof is to provide a liquid crystal alignment film that has a uniform film quality and excellent electrical characteristics and heat resistance even when it is left for a long time after coating. It is in providing the liquid crystal aligning agent which can be performed.
Another object of the present invention is to provide a liquid crystal display element capable of high-quality display and suppressing deterioration of display quality when driven for a long time.
Still other objects and advantages of the present invention will become apparent from the following description.

According to the present invention, the object of the present invention is firstly as follows:
At least one polymer selected from the group consisting of polyamic acid and polyimide, provided that at least a part of the polymer has the following formula (A ′):
_{^{R I - (X I) n1}} -R II -O-X II -COO- (R III O) n2 - * (A ')
(In Formula (A ′), R ^I is an alkyl group having 1 to 30 carbon atoms or a fluoroalkyl group having 1 to 30 carbon atoms, and R ^II is a single bond, a methylene group or an alkylene group having 2 to 30 carbon atoms. R ^III is an alkylene group having 2 to 5 carbon atoms, and X ^I and X ^II are a divalent alicyclic group, a divalent heterocyclic group, an arylene group, or a divalent heteroaromatic group, respectively. A plurality of groups X ^I may be the same or different from each other, n1 is an integer of 2 to 5, n2 is an integer of 0 to 10, and “*” is a bond. (Indicates that
The liquid crystal aligning agent characterized by containing the group represented by these.
The above object of the present invention is secondly,
This is achieved by a liquid crystal display element comprising a liquid crystal alignment film formed from the above liquid crystal aligning agent.

The liquid crystal aligning agent of the present invention can provide a liquid crystal aligning film having a uniform film quality and excellent electrical characteristics and heat resistance even when it is left for a long time after coating.
The liquid crystal display element of the present invention comprising the liquid crystal alignment film formed from the liquid crystal aligning agent of the present invention is capable of high-quality display, and suppresses deterioration of display quality when driven for a long time. It is. Therefore, the liquid crystal display element of the present invention can be effectively applied to various devices, such as watches, portable games, word processors, notebook computers, car navigation systems, camcorders, portable information terminals, digital cameras, cellular phones, It can be suitably used for display devices such as various monitors and liquid crystal televisions.

¹ H-NMR chart of the compound (A-1-1) obtained in Synthesis Example A-1. ¹ H-NMR chart of compound (A-2-1) obtained in Synthesis Example A-2. ¹ H-NMR chart of Compound (A-2-2) obtained in Synthesis Example A-3.

Hereinafter, the present invention will be described in detail.
The liquid crystal aligning agent of the present invention is at least one polymer selected from the group consisting of polyamic acid and polyimide, provided that the polymer has a group represented by the above formula (A ′) in at least a part of the molecule. It has. Hereinafter, such a polymer is referred to as a “specific polymer” in the present specification.
As the alkyl group having 1 to 30 carbon atoms of R ¹ in the above formula (A ′), a linear alkyl group having 1 to 12 carbon atoms is preferable, and n-propyl group, n-butyl group, n is particularly preferable. -Pentyl group, n-hexyl group, n-heptyl group, n-octyl group and the like can be mentioned.
Preferable examples of the fluoroalkyl group having 1 to 30 carbon atoms of R ^I include, for example, the following formula (R ^I -1)
C _i F _{2i + 1} −C _j H _2j − (R ^I −1)
(In the above formula, i is an integer of 1 to 30, j is an integer of 0 to 29, where i + j is an integer of 1 to 30.)
And is more preferably a linear group represented by the above formula (R ^I -1). Specific examples thereof include, for example, a trifluoromethyl group, 4, 4, 5 , 5,5-pentafluoropentyl group and the like.
R ^II in the above formula (A ′) is preferably a single bond or a methylene group, and particularly preferably a methylene group.
R ^III in the above formula (A ′) is preferably an alkylene group having 2 or 3 carbon atoms, and specific examples thereof include, for example, 1,2-ethylene group, 1,2-propylene group, 1,3- A propylene group etc. can be mentioned. Of these, a 1,2-ethylene group or a 1,2-propylene group is more preferable. The bonding direction of the 1,2-propylene group is not limited. R ^III is particularly preferably a 1,2-ethylene group.

Examples of the divalent alicyclic group X ^I and X ^II in the above formula (A '), respectively, can be, for example, a divalent alicyclic group having 3 to 8 carbon atoms, for example, as a specific example A 1,4-cyclohexylene group, a 1,3-cyclohexylene group, a 1,3-cyclopentylene group, and the like can be given. The divalent heterocyclic group X ^I and X ^II, respectively, for example, can be a divalent heterocyclic alicyclic group having 3 to 8 carbon atoms, such as piperidine. Specific examples thereof 1,4 A diyl group, a piperazine-1,4-diyl group, etc. can be mentioned. The arylene group of X ^I and X ^II can be, for example, an arylene group having 6 to 12 carbon atoms, and specific examples thereof include, for example, 1,4-phenylene group, 1,3-phenylene group, naphthalene-2 , 6-diyl group, naphthalene-2,7-diyl group, naphthalene-1,5-diyl group, and the like. Examples of the divalent heteroaromatic groups X ^I and X ^II, respectively, for example, be a divalent heteroaromatic group having 4 to 8 carbon atoms, for example, pyridine-2,5-diyl As specific examples Group, pyridine-2,6-diyl group, pyrazine-2,5-diyl group, pyrazine-2,6-diyl group, pyrimidine-2,5-diyl group, pyrrole-2,5-diyl group, imidazole-1 , 4-diyl group, pyrazole-1,3-diyl group, pyrazole-1,4-diyl group and the like. C 3-8 divalent alicyclic group, C 3-8 divalent heterocyclic group, C 6-12 arylene group, and C 4-8 carbon atoms of X ^I and X ^II Each of the divalent heteroaromatic groups may be substituted with one or more fluorine atoms or an alkyl group having 1 to 12 carbon atoms.

It The X ^I in the above formula (A ') is a divalent alicyclic group, n1 is preferably respectively a 2. In the above formula (A ′), (X ^I ) _n1 is particularly preferably a 4,4′-bicyclohexylene group.
The ^{X II} in the above formula (A '), is preferably an arylene group, particularly preferably a 1,4-phenylene group.
In the above formula (A ′), n2 is preferably 0 or 1.

The polyamic acid having a group represented by the above formula (A ′) in at least a part of the molecule includes, for example, a tetra-compound containing a group represented by the above formula (A ′) and a compound having two carboxylic anhydride groups. Carboxylic dianhydride and diamine are reacted, or tetracarboxylic dianhydride and diamine containing a compound represented by the above formula (A ′) and two amino groups are reacted. Can be obtained by
A polyimide having a group represented by the above formula (A ′) in at least a part of the molecule can be obtained, for example, by dehydrating and ring-closing the polyamic acid obtained as described above.
As the specific polymer contained in the liquid crystal aligning agent of the present invention, a tetracarboxylic dianhydride and a diamine containing a compound having a structure represented by the above formula (A ′) and two amino groups are reacted. It is preferable that the polymer is at least one polymer selected from the group consisting of a polyamic acid obtained by the above-described process and a polyimide formed by dehydrating and ring-closing the polyamic acid.

<Polyamic acid>
[Tetracarboxylic dianhydride]
Examples of the tetracarboxylic dianhydride used for the synthesis of a preferred polyamic acid in the liquid crystal aligning agent of the present invention include, for example, butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic 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, , 3,5-tricarboxycyclopentylacetic acid dianhydride, 2,3,4,5-tetrahydrofurantetracarboxylic 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-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-furanyl) -naphtho [1,2-c] -furan-1,3-dio , Bicyclo [2.2.2] -oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 3-oxabicyclo [3.2.1] octane-2,4-dione- 6-spiro-3 ′-(tetrahydrofuran-2 ′, 5′-dione), 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride Product, 3,5,6-tricarboxy-2-carboxymethylnorbornane-2: 3,5: 6-dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] undecane -3,5,8,10-tetraone, the following formulas (TI) and (T-II)

(Wherein R ¹ and R ³ are each a divalent organic group having an aromatic ring, R ² and R ⁴ are each a hydrogen atom or an alkyl group, and a plurality of R ² and R ^{4 are present.} May be the same or different.)
An aliphatic tetracarboxylic dianhydride and an alicyclic tetracarboxylic dianhydride such as a compound represented by each of the following:
Pyromellitic dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenylsulfone tetracarboxylic dianhydride, 1,4,5, 8-naphthalene tetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenyl ether tetracarboxylic dianhydride, 3,3 ′, 4,4′-dimethyldiphenylsilanetetracarboxylic dianhydride, 3,3 ′, 4,4′-tetraphenylsilanetetracarboxylic dianhydride, 1,2,3,4-furantetracarboxylic dianhydride 4,4′-bis (3,4-dicarboxyphenoxy) diphenyl sulfide dianhydride, 4,4′-bis (3,4-dicarboxyphenoxy) diphenylsulfone dianhydride, 4,4′-bis ( 3,4-dicar Boxyphenoxy) diphenylpropane dianhydride, 3,3 ′, 4,4′-perfluoroisopropylidene diphthalic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2 , 2 ′, 3,3′-biphenyltetracarboxylic dianhydride, bis (phthalic acid) phenylphosphine oxide 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 ( Anhydrotrimellitate), propylene glycol-bis (anhydrotrimellitate), 1,4-butanediol-bis (anhydrotrimellitate) Retate), 1,6-hexanediol-bis (anhydrotrimellitate), 1,8-octanediol-bis (anhydrotrimellitate), 2,2-bis (4-hydroxyphenyl) propane-bis ( Anhydrotrimellitate), the following formulas (T-1) to (T-4)

An aromatic tetracarboxylic dianhydride such as a compound represented by each of the above can be exemplified. The benzene ring of the aromatic tetracarboxylic dianhydride may be substituted with one or two or more alkyl groups having 1 to 4 carbon atoms (preferably a methyl group).
These tetracarboxylic dianhydrides can be used singly or in combination of two or more.
Among tetracarboxylic dianhydrides used for the synthesis of preferred polyamic acids in the present invention, among the above, butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1, 3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid 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-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, bicyclo [ 2.2.2] -Oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 3-oxabicyclo [3.2.1] octane-2,4-dione-6-spiro -3 ′-(tetrahydrofuran-2 ′, 5′-dione), 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride, 3 , 5,6-tricarboxy-2-carboxymethylnorbornane-2: 3,5: 6-dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] undecane-3, 5,8,10-tetraone, pyromellitic dianhydride 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenylsulfonetetracarboxylic dianhydride, 2,2 ′, 3,3′-biphenyltetra Carboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, among the compounds represented by the above formula (TI), the following formulas (T-5) to (T-7)

And the following formula (T-8) among the compounds represented by formula (T-II):

The liquid crystal alignment film to be formed exhibits good liquid crystal alignment properties when it contains at least one selected from the group consisting of the compounds represented by (hereinafter referred to as “specific tetracarboxylic dianhydride”). It is preferable from the viewpoint of becoming.
More preferably, the specific tetracarboxylic dianhydride is 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid 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, 3-oxabicyclo [3.2.1] octane -2,4-dione-6-spiro-3 '-(tetrahydrofuran-2', 5'-dione), 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene- 1,2-dicarbo Acid anhydride, 3,5,6-tricarboxy-2-carboxymethyl norbornane -2: 3,5: 6-dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^{2, 6} ] At least one selected from the group consisting of undecane-3,5,8,10-tetraone, pyromellitic dianhydride and the compound represented by the above formula (T-5), particularly preferably 2,3 , 5-tricarboxycyclopentylacetic acid dianhydride.
The tetracarboxylic dianhydride used for the synthesis of a preferred polyamic acid in the present invention contains 10 mol% or more of the specific tetracarboxylic dianhydride as described above with respect to the total tetracarboxylic dianhydride. The content is preferably 30 mol%, more preferably 40 mol% or more.
As the tetracarboxylic dianhydride used for the synthesis of a preferable polyamic acid in the present invention, it is most preferable to use only the specific tetracarboxylic dianhydride as described above.

[Diamine]
The diamine used for the synthesis | combination of the preferable polyamic acid in this invention contains the compound which has the group represented by the said Formula (A '), and two amino groups.
As a compound having a group represented by the above formula (A ′) and two amino groups, the following formula (A):

(In the formula (A), R ^I , R ^II , R ^III , X ^I , X ^II , n1 and n2 are respectively synonymous with those in the above formula (A ′).)
It is preferable that it is a compound represented by these. In the above formula (A), the two amino groups bonded to the benzene ring are preferably in the 2,4-position or 3,5-position.
As more specific examples of the compound represented by the above formula (A), for example, the following formulas (A-1) to (A-4):

(In formulas (A-1) to (A-4), R ^I has the same meaning as in formula (A) above.)
The compound represented by each of these can be mentioned.
The compound represented by the above formula (A) can be synthesized by appropriately combining conventional methods for organic compounds. For example, the compound represented by the above formula (A-1) is, for example, the following scheme:

(In the above scheme, R ^I has the same meaning as in the above formula (A).)
Can be synthesized according to That is, a compound (Aa) having a desired group R ^I is reacted with p-chlorobenzenesulfonic acid chloride to obtain a compound (Ab). Further, the compound (Ab), ethyl 4-hydroxybenzoate, To obtain a compound (Ac), followed by hydrolysis in the presence of a suitable alkali, for example, to obtain an intermediate (Ad). This intermediate (Ad) and 3,5 -After reacting with bis (diallylamino) phenol (compound B) to give compound (A-1e), preferably allylation in the presence of N, N-dimethylbarbituric acid and tetrakis (triphenylphosphine) palladium By doing so, it can be synthesized. The compound (B) used here can be easily obtained by reacting 1,3,5-trihydroxybenzene and 2 equivalents of diallylamine.
Moreover, the compound represented by the said Formula (A-3) is the following scheme, for example.

(In the above scheme, R ^I has the same meaning as in the above formula (A).)
Can be synthesized according to That is, the intermediate (Ad) obtained in the same manner as described above and 1-hydroxy-2,4-dinitrobenzene are reacted to form a compound (A-3e), and then an appropriate compound such as palladium carbon and hydrogen is used. It can be synthesized by converting a nitro group to an amino group using a reducing system.
As the diamine used for synthesizing a preferred polyamic acid in the present invention, only the compound represented by the above formula (A) may be used alone, or the compound represented by the above formula (A) and other diamines. And may be used in combination.

  Examples of other diamines that can be used here include p-phenylenediamine, m-phenylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylethane, 4,4′-diaminodiphenyl sulfide, 4,4′-diaminodiphenyl sulfone, 3,3′-dimethyl-4,4′-diaminobiphenyl, 4,4′-diaminobenzanilide, 4,4′-diaminodiphenyl ether, 1,5-diaminonaphthalene, 2, 2'-dimethyl-4,4'-diaminobiphenyl, 5-amino-1- (4'-aminophenyl) -1,3,3-trimethylindane, 6-amino-1- (4'-aminophenyl)- 1,3,3-trimethylindane, 3,4'-diaminodiphenyl ether, 3,3'-diaminobenzo Enone, 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-aminophenyl) hexafluoropropane, bis [4- (4-aminophenoxy) phenyl] sulfone, 1,4-bis (4-aminophenoxy) benzene, 4, 4'-bis (4-aminophenoxy) biphenyl, 1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 9,9-bis (4-aminophenyl)- 10-hydroanthracene, 2,7-diaminofluorene, 9,9-dimethyl-2,7-diaminofluorene, 9,9-bis (4 Aminophenyl) fluorene, bis (4-amino-2-chlorophenyl) methane, 2,2 ′, 5,5′-tetrachloro-4,4′-diaminobiphenyl, 2,2′-dichloro-4,4′- Diamino-5,5′-dimethoxybiphenyl, 3,3′-dimethoxy-4,4′-diaminobiphenyl, 4,4 ′-(p-phenylenediisopropylidene) bisaniline, 4,4 ′-(m-phenylenedi Isopropylidene) bisaniline, 2,2′-bis [4- (4-amino-2-trifluoromethylphenoxy) phenyl] hexafluoropropane, 4,4′-diamino-3,3′-bis (trifluoromethyl) Biphenyl, 4,4′-diamino-2,2′-bis (trifluoromethyl) biphenyl, 4,4′-bis [(4-amino-2-trifluoro) Methyl) phenoxy] - octafluorobiphenyl, 3,5-diaminobenzoic acid, 2,4-diaminobenzoic acid, the following formula (D-1) ~ (D-5)

(Y in the formula (D-4) is an integer of 2 to 12, and z in the formula (D-5) is an integer of 1 to 5.)
An aromatic diamine such as a compound represented by each of the following:
1,1-metaxylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, 1,4-diaminocyclohexane, isophoronediamine, Tetrahydrodicyclopentadienylenediamine, hexahydro-4,7-methanoindanylene methylenediamine, tricyclo [6.2.1.0 ^2,7 ] -undecylenediethylenediamine, 4,4′-methylenebis (cyclohexylamine) ), 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane and other aliphatic and alicyclic diamines;
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-diamino-2-vinyl-s-triazine, 2,4-diamino-5-phenylthiazole, 2,6- Aminopurine, 5,6-diamino-1,3-dimethyluracil, 3,5-diamino-1,2,4-triazole, 3,8-diamino-6-phenylphenanthridine, 1,4-diaminopiperazine, 3,6-diaminoacridine, N, N′-bis (4-aminophenyl) phenylamine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, N-ethyl-3,6-diaminocarbazole N-phenyl-3,6-diaminocarbazole, N, N′-bis (4-aminophenyl) -benzidine, N, N′-bis (4-aminophenyl) -N, N′-dimethyl-benzidine, and The following formulas (D-I) and (D-II)

(In the formula (DI), R ⁵ is a monovalent organic group having a ring structure containing a nitrogen atom selected from the group consisting of pyridine, pyrimidine, triazine, piperidine and piperazine, and X ¹ is a divalent group. An organic group;
In the formula (D-II), R ⁶ is a divalent organic group having a ring structure containing a nitrogen atom selected from the group consisting of pyridine, pyrimidine, triazine, piperidine and piperazine, and X ² is 2 And a plurality of X ² may be the same or different. )
A diamine having two primary amino groups in the molecule and a nitrogen atom other than the primary amino group, such as a compound represented by each of:
The following formula (D-III)

(In the formula (D-III), R ⁷ is —O—, —COO—, —OCO—, —NHCO—, —CONH— or —CO—, and R ⁸ is a steroid skeleton, a trifluoromethylphenyl group, A monovalent organic group having a skeleton or group selected from the group consisting of a trifluoromethoxyphenyl group and a fluorophenyl group, or an alkyl group having 6 to 30 carbon atoms.)
Monosubstituted phenylenediamines such as compounds represented by:
The following formula (D-IV)

(In the formula (D-IV), R ⁹ is a hydrocarbon group having 1 to 12 carbon atoms, and a plurality of R ⁹ may be the same or different, and p is each 1 is an integer of 1 to 3, and q is an integer of 1 to 20.)
And diaminoorganosiloxanes such as compounds represented by the formula: The aromatic diamine, a diamine ring having two primary amino groups in the molecule and a nitrogen atom other than the primary amino group, and a mono-substituted phenylenediamine have one or two or more carbon atoms of 1 to 4 May be substituted with an alkyl group (preferably a methyl group). In addition, the steroid skeleton in the above formula (D-III) refers to a skeleton composed of a cyclopentano-perhydrophenanthrene nucleus or a skeleton in which one or more of the carbon-carbon bonds are double bonds.
These diamines can be used alone or in combination of two or more.

  Other diamines used for synthesizing a preferred polyamic acid in the present invention include p-phenylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl sulfide, and 1,5-diamino among the above. Naphthalene, 2,2′-dimethyl-4,4′-diaminobiphenyl, 4,4′-diamino-2,2′-bis (trifluoromethyl) biphenyl, 2,7-diaminofluorene, 4,4′-diamino Diphenyl 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 '-( -Phenylenediisopropylidene) bisaniline, 4,4 '-(m-phenylenediisopropylidene) bisaniline, 1,4-bis (4-aminophenoxy) benzene, 4,4'-bis (4-aminophenoxy) biphenyl, 1,4-diaminocyclohexane, 4,4′-methylenebis (cyclohexylamine), 1,3-bis (aminomethyl) cyclohexane, compounds represented by the above formulas (D-1) to (D-5), 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminoacridine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, N-ethyl- 3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, N, N′-bis ( -Aminophenyl) -benzidine, N, N'-bis (4-aminophenyl) -N, N'-dimethylbenzidine, 3,5-diaminobenzoic acid, among the compounds represented by the above formula (DI) The following formula (D-6)

Of the compounds represented by formula (D-II), the following formula (D-7)

Of the compounds represented by formula (D-III), dodecanoxy-2,4-diaminobenzene, pentadecanoxy-2,4-diaminobenzene, hexadecanoxy-2,4-diaminobenzene, octadecanoxy- 2,4-diaminobenzene, dodecanoxy-2,5-diaminobenzene, pentadecanoxy-2,5-diaminobenzene, hexadecanoxy-2,5-diaminobenzene, octadecanoxy-2,5-diaminobenzene, the following formula (D-8) ~ (D-15)

And at least one selected from the group consisting of 1,3-bis (3-aminopropyl) -tetramethyldisiloxane among the compounds represented by formula (D-IV) , "Other specific diamine") is preferably used.
It is preferable that the diamine used for the synthesis | combination of the preferable polyamic acid in this invention contains 0.1 mol% or more of compounds represented by the said Formula (A) with respect to all the diamine, 0.5-50 mol. %, More preferably 1 to 40 mol%.
It is preferable that the diamine used for the synthesis | combination of the preferable polyamic acid in this invention contains the above other specific diamine other than the compound represented by the said Formula (A). In this case, the use ratio of the other specific diamine is preferably 30 mol% or more, more preferably 30 to 99.9 mol%, more preferably 50 to 99.5 mol% with respect to the total diamine. More preferably, it is particularly preferable to contain 60 to 99 mol%.
It is preferable that the diamine used for the synthesis | combination of the preferable polyamic acid in this invention consists only of the compound represented by the said Formula (A), and another specific diamine.

[Synthesis of polyamic acid]
A preferable polyamic acid in the present invention can be obtained by reacting a tetracarboxylic dianhydride with a diamine containing a compound represented by the above formula (A).
The ratio of the tetracarboxylic dianhydride and the diamine used in the polyamic acid synthesis reaction is 0.2 to 2 for the tetracarboxylic dianhydride acid anhydride group to 1 equivalent of the amino group of the diamine. The ratio which becomes an equivalent is preferable, More preferably, it is the ratio which becomes 0.3-1.2 equivalent.
The polyamic acid synthesis reaction is preferably performed in an organic solvent, preferably at a temperature of −20 ° C. to 150 ° C., more preferably 0 to 100 ° C., and preferably 0.1 to 24 hours, more preferably 0.00. 5 to 12 hours.
Examples of the organic solvent that can be used in the synthesis of the polyamic acid include an aprotic polar solvent, phenol and derivatives thereof, alcohol, ketone, ester, ether, halogenated hydrocarbon, hydrocarbon and the like.

Examples of the aprotic polar solvent include N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethyl sulfoxide, γ-butyrolactone, tetramethylurea, hexamethylphosphortriamide and the like. ;
Examples of the phenol derivative include m-cresol, xylenol, halogenated phenol and the like;
Examples of the alcohol include methyl alcohol, ethyl alcohol, isopropyl alcohol, cyclohexanol, ethylene glycol, propylene glycol, 1,4-butanediol, triethylene glycol, and ethylene glycol monomethyl ether;
Examples of the ketone include acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone;
Examples of the ester include ethyl lactate, butyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, diethyl oxalate, and diethyl malonate;
Examples of the ether include 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, etc .;
Examples of the halogenated hydrocarbon include dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, o-dichlorobenzene and the like;
Examples of the hydrocarbon include hexane, heptane, octane, benzene, toluene, xylene, isoamylpropionate, isoamylisobutyrate, and diisopentyl ether.

Among these organic solvents, one or more selected from the group consisting of an aprotic polar solvent and phenol and derivatives thereof (first group organic solvent), or one or more selected from the first group of organic solvents It is preferable to use a mixture with one or more selected from the group consisting of alcohols, ketones, esters, ethers, halogenated hydrocarbons and hydrocarbons (second group organic solvent). In the latter case, the use ratio of the second group of organic solvents is preferably 50% by weight or less, more preferably 40% by weight or less, with respect to the total of the first group of organic solvents and the second group of organic solvents. Furthermore, it is preferable that it is 30 weight% or less.
As described above, a reaction solution obtained by dissolving polyamic acid is obtained.
This reaction solution may be used as it is for the preparation of the liquid crystal aligning agent, may be used for the preparation of the liquid crystal aligning agent after isolating the polyamic acid contained in the reaction solution, or the isolated polyamic acid was purified. You may use for preparation of a liquid crystal aligning agent.
When polyamic acid is dehydrated and cyclized into a polyimide, the above reaction solution may be directly subjected to dehydration and cyclization reaction, or may be subjected to dehydration and cyclization reaction after isolating the polyamic acid contained in the reaction solution. Alternatively, the isolated polyamic acid may be purified and then subjected to a dehydration ring closure reaction.
The polyamic acid is isolated by pouring the reaction solution into a large amount of poor solvent to obtain a precipitate, and drying the precipitate under reduced pressure, or by distilling off the solvent in the reaction solution under reduced pressure using an evaporator. It can be carried out. Alternatively, the polyamic acid is dissolved again in an organic solvent and then precipitated with a poor solvent, or the solution obtained by dissolving the polyamic acid again in the organic solvent is washed, and then the solvent in the solution is reduced in pressure by an evaporator. The polyamic acid can be purified by a method of performing the step of distilling once or several times.

<Polyimide>
A preferred polyimide in the present invention can be obtained by dehydrating and ring-closing the polyamic acid as described above to imidize.
Examples of the tetracarboxylic dianhydride used for the synthesis of the polyimide include the same compounds as the tetracarboxylic dianhydride used for the synthesis of the polyamic acid described above. The kind of preferable tetracarboxylic dianhydride and its preferable usage rate are the same as in the case of polyamic acid.
Examples of the diamine used for synthesizing a preferable polyimide in the present invention include the same diamines as those used for the synthesis of the polyamic acid. That is, the diamine used for the synthesis | combination of the polyimide contained in the liquid crystal aligning agent of this invention contains the compound represented by the said Formula (A), and uses only the compound represented by the said Formula (A). Alternatively, the compound represented by the formula (A) and the other diamine may be used in combination. The types of other preferred diamines and the preferred use ratio of each diamine are the same as in the case of polyamic acid.
The preferred polyimide in the present invention may be a completely imidized product obtained by dehydrating and cyclizing all of the amic acid structure that the polyamic acid as a raw material had, or by dehydrating and cyclizing only a part of the amic acid structure. And a partially imidized product in which the imide ring structure coexists. The imidation ratio of the polyimide in the present invention is preferably 30% or more, more preferably 40% or more, and particularly preferably 45% or more. This imidation ratio represents the ratio of the number of imide ring structures to the total of the number of polyimide amic acid structures and the number of imide ring structures in percentage. At this time, a part of the imide ring may be an isoimide ring.

The dehydration ring closure of the polyamic acid is preferably performed by (i) a method of heating the polyamic acid, or (ii) dissolving the polyamic acid in an organic solvent, and adding a dehydrating agent and a dehydration ring closure catalyst to this solution as necessary. This is done by heating.
The reaction temperature in the method (i) of heating the polyamic acid is preferably 50 to 200 ° C, more preferably 60 to 170 ° C. When the reaction temperature is less than 50 ° C., the dehydration ring-closing reaction does not proceed sufficiently, and when the reaction temperature exceeds 200 ° C., the molecular weight of the resulting polyimide may decrease. The reaction time is preferably 1.0 to 24 hours, more preferably 1.0 to 12 hours.
On the other hand, in the method (ii) of adding a dehydrating agent and a dehydrating ring-closing catalyst to the polyamic acid solution, an acid anhydride such as acetic anhydride, propionic anhydride, or trifluoroacetic anhydride is used as the dehydrating agent. Can do. Although the usage-amount of a dehydrating agent is based on the imidation ratio desired, it is preferable to set it as 0.01-20 mol with respect to 1 mol of the amic acid structure of a polyamic acid. Moreover, as a dehydration ring closure catalyst, tertiary amines, such as a pyridine, a collidine, a lutidine, a triethylamine, can be used, for example. However, it is not limited to these. It is preferable that the usage-amount of a dehydration ring-closing catalyst shall be 0.01-10 mol with respect to 1 mol of dehydrating agents to be used. The imidation rate can be increased as the amount of the above dehydrating agent and dehydrating ring-closing agent increases. Examples of the organic solvent used in the dehydration ring-closing reaction include the organic solvents exemplified as those used for the synthesis of polyamic acid. The reaction temperature of the dehydration ring closure reaction is preferably 0 to 180 ° C, more preferably 10 to 150 ° C. The reaction time is preferably 1.0 to 120 hours, more preferably 2.0 to 30 hours.

  The polyimide obtained in the above method (i) may be used for the preparation of the liquid crystal aligning agent as it is, or may be used for the preparation of the liquid crystal aligning agent after purifying the obtained polyimide. On the other hand, in the above method (ii), a reaction solution containing polyimide is obtained. This reaction solution may be used as it is for the preparation of the liquid crystal aligning agent, or may be used for the preparation of the liquid crystal aligning agent after removing the dehydrating agent and the dehydrating ring-closing catalyst from the reaction solution. It may be used for the preparation of a liquid crystal aligning agent or may be used for the preparation of a liquid crystal aligning agent after purifying the isolated polyimide. In order to remove the dehydrating agent and the dehydrating ring-closing catalyst from the reaction solution, for example, a method such as solvent replacement can be applied. The isolation and purification of the polyimide can be performed by performing the same operation as described above as the isolation and purification method of the polyamic acid.

-End-modified polymer-
In the present invention, the polyamic acid and the polyimide may each be a terminal-modified polymer having a controlled molecular weight. By using the terminal-modified polymer, the coating properties of the liquid crystal aligning agent can be further improved without impairing the effects of the present invention. Such a terminal-modified polymer can be obtained by adding a molecular weight modifier to a polymerization reaction system when synthesizing a polyamic acid. Examples of molecular weight regulators include acid monoanhydrides, monoamine compounds, monoisocyanate compounds, and the like.
Examples of the acid monoanhydride include maleic anhydride, phthalic anhydride, itaconic anhydride, n-decylsuccinic anhydride, n-dodecylsuccinic anhydride, n-tetradecylsuccinic anhydride, n -Hexadecyl succinic anhydride etc .;
Examples of the monoamine compound include aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, n-undecylamine, n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecylamine, n-octadecylamine, n-eicosylamine and the like;
Examples of the monoisocyanate compound include phenyl isocyanate and naphthyl isocyanate.
The use ratio of the molecular weight modifier is preferably 20 parts by weight or less, more preferably 10 parts by weight or less, with respect to 100 parts by weight of the total of tetracarboxylic dianhydride and diamine used when synthesizing the polyamic acid. .
-Solution viscosity-
The polyamic acid or polyimide obtained as described above preferably has a solution viscosity of 20 to 800 mPa · s, and has a solution viscosity of 30 to 500 mPa · s when a 10% by weight solution is obtained. It is more preferable to have it.
The solution viscosity (mPa · s) of the above polymer is E for a polymer solution having a concentration of 10% by weight prepared using a good solvent for the polymer (for example, γ-butyrolactone, N-methyl-2-pyrrolidone, etc.). It is a value measured at 25 ° C. using a mold rotational viscometer.

<Other ingredients>
The liquid crystal alignment film of the present invention contains the specific polymer as described above as an essential component, but may contain other components as necessary. Examples of such other components include other polymers, compounds having at least one epoxy group in the molecule (hereinafter referred to as “epoxy compound”), and functional silane compounds.
[Other polymers]
These other polymers can be used to improve solution and electrical properties. Such other polymer is a polymer other than the specific polymer, for example, a polyamic acid (hereinafter referred to as “polyamic acid”) obtained by reacting tetracarboxylic dianhydride with a diamine not containing the compound represented by the above formula (A). , "Other polyamic acid"), polyimide obtained by dehydrating and ring-closing the polyamic acid (hereinafter referred to as "other polyimide"), polyamic acid ester, polyester, polyamide, polysiloxane, cellulose derivative, polyacetal, polystyrene Derivatives, poly (styrene-phenylmaleimide) derivatives, poly (meth) acrylates and the like can be mentioned. Of these, other polyamic acids or other polyimides are preferred, and other polyamic acids are more preferred.
The proportion of the other polymer used is preferably 50% by weight or less, more preferably 40% by weight based on the total of the polymers (the above-mentioned specific polymer and other polymers are the same hereinafter). It is preferably not more than wt%, more preferably not more than 30 wt%.

[Epoxy compound]
Examples of the epoxy compound include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, and 1,6-hexane. Diol diglycidyl ether, glycerin diglycidyl ether, trimethylolpropane triglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, 1,3 -Bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N ', N'-tetraglycidyl-4,4'-diaminodiphenylme Emissions, N, N-diglycidyl - benzylamine, N, N-diglycidyl - aminomethyl cyclohexane, N, N-diglycidyl - cyclohexyl amine may be mentioned as preferred.
The compounding ratio of these epoxy compounds is preferably 40 parts by weight or less, more preferably 0.1 to 30 parts by weight with respect to 100 parts by weight of the total amount of the polymer.

[Functional silane compounds]
Examples of the functional silane compound include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl)- 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyl Trimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4 7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9- Triethoxysilyl-3,6-diazanonyl acetate, methyl 9-trimethoxysilyl-3,6-diazananoate, methyl 9-triethoxysilyl-3,6-diazananoate, N-benzyl-3-aminopropyltri Methoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, glycidoxymethyltrimethoxysilane, glycidoxy Methyltriethoxysilane, 2-glycidoxyethyltrimeth Shishiran, 2-glycidoxyethyl triethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 3-glycidoxypropyl triethoxy silane and the like.
The blending ratio of these functional silane compounds is preferably 2 parts by weight or less, more preferably 0.02 to 0.2 parts by weight with respect to 100 parts by weight of the total amount of the polymer.

In the liquid crystal aligning agent of the present invention, at least one polymer selected from the group consisting of the above polyamic acid and polyimide, and other additives optionally blended as necessary, are preferably in an organic solvent. Dissolved and contained in the composition.
Examples of the organic solvent that can be used in the liquid crystal aligning agent of the present invention include N-methyl-2-pyrrolidone, γ-butyrolactone, γ-butyrolactam, N, N-dimethylformamide, N, N-dimethylacetamide, 4-hydroxy-4. -Methyl-2-pentanone, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n-propyl ether, Ethylene glycol-i-propyl ether, 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, diisobutyl ketone, isoamyl propionate, isoamyl isobutyrate, diisopentyl ether, ethylene carbonate, propylene carbonate, etc. Can be mentioned. These can be used alone or in admixture of two or more.

The solid content concentration in the liquid crystal aligning agent of the present invention (the ratio of the total weight of components other than the solvent of the liquid crystal aligning agent to the total weight of the liquid crystal aligning agent) is appropriately selected in consideration of viscosity, volatility, and the like. The range is preferably 1 to 10% by weight. That is, the liquid crystal aligning agent of the present invention is applied to the substrate surface as described later, and preferably, when heated, a coating film that becomes a liquid crystal aligning film is formed, but the solid content concentration is less than 1% by weight. In this case, the film thickness of the coating film becomes too small to obtain a good liquid crystal alignment film. On the other hand, when the solid content concentration exceeds 10% by weight, the film thickness of the coating film becomes excessive. Thus, a good liquid crystal alignment film cannot be obtained, and the viscosity of the liquid crystal aligning agent increases, resulting in poor coating properties.
The particularly preferable range of the solid content concentration varies depending on the method used when the liquid crystal aligning agent is applied to the substrate. For example, when the spinner method is used, the solid content concentration is particularly preferably in the range of 1.5 to 4.5% by weight. In the case of the printing method, it is particularly preferable that the solid content concentration is in the range of 3 to 9% by weight, and thereby the solution viscosity is in the range of 12 to 50 mPa · s. In the case of the inkjet method, it is particularly preferable that the solid content concentration is in the range of 1 to 5% by weight, and thereby the solution viscosity is in the range of 3 to 15 mPa · s.
The temperature at the time of preparing the liquid crystal aligning agent of this invention becomes like this. Preferably it is 10 to 50 degreeC, More preferably, it is 20 to 30 degreeC.

<Liquid crystal display element>
The liquid crystal display element of the present invention comprises a liquid crystal alignment film formed from the liquid crystal aligning agent of the present invention as described above.
The liquid crystal display element of the present invention can be produced, for example, by the following steps (1) to (3). In step (1), the substrate to be used varies depending on the desired operation mode. Steps (2) and (3) are common to each operation mode.
(1) First, the liquid crystal aligning agent of this invention is apply | coated on a board | substrate, Then, a coating film is formed on a board | substrate by heating an application surface.

(1-1) When manufacturing a TN type, STN type, or VA type liquid crystal display element, a pair of two substrates provided with a patterned transparent conductive film is used as a pair on each transparent conductive film formation surface. The liquid crystal aligning agent of the present invention is preferably applied by an offset printing method, a spin coating method or an ink jet printing method, respectively, and then each coated surface is heated to form a coating film. Here, as the substrate, for example, a glass such as float glass or soda glass; a transparent substrate made of a plastic such as polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polycarbonate, or poly (alicyclic olefin) can be used. As a transparent conductive film provided on one surface of the substrate, an NESA film (registered trademark of PPG, USA) made of tin oxide (SnO ₂ ), an ITO film made of indium oxide-tin oxide (In ₂ O ₃ —SnO ₂ ), etc. In order to obtain a patterned transparent conductive film which can be used, for example, a method of forming a pattern by photo-etching after forming a transparent conductive film without a pattern, a mask having a desired pattern when forming the transparent conductive film The method using can be used. When applying the liquid crystal aligning agent, in order to further improve the adhesion between the substrate surface and the transparent conductive film and the coating film, a functional silane compound or functional titanium is formed on the surface of the substrate surface on which the coating film is to be formed. You may give the pretreatment which apply | coats a compound etc. previously.
After application of the liquid crystal aligning agent, preheating (pre-baking) is preferably performed for the purpose of preventing dripping of the applied aligning agent. The pre-baking temperature is preferably 30 to 200 ° C, more preferably 40 to 150 ° C, and particularly preferably 40 to 100 ° C. The pre-bake time is preferably 0.25 to 10 minutes, more preferably 0.5 to 5 minutes. Then, a baking (post-baking) process is implemented for the purpose of removing a solvent completely, and heat imidizing a polyamic acid as needed. The firing (post-bake) temperature is preferably 80 to 300 ° C, more preferably 120 to 250 ° C, and the post-bake time is preferably 5 to 200 minutes, more preferably 10 to 100 minutes. Thus, the film thickness of the formed film is preferably 0.001 to 1 μm, more preferably 0.005 to 0.5 μm.
(1-2) On the other hand, when manufacturing an IPS type liquid crystal display element, the conductive film forming surface of the substrate provided with the comb-shaped transparent conductive film and the counter substrate provided with no conductive film On one surface, the liquid crystal aligning agent of the present invention is preferably applied by an offset printing method, a spin coating method, or an ink jet printing method, and then each coated surface is heated to form a coating film.
The material used for the substrate and the transparent conductive film, the patterning method for the transparent conductive film, the pretreatment of the substrate, and the heating method after applying the liquid crystal aligning agent are the same as in (1-1) above.
The preferable film thickness of the coating film to be formed is the same as (1-1) above.

(2) When the liquid crystal display element manufactured by the method of the present invention is a VA liquid crystal display element, the coating film formed as described above can be used as a liquid crystal alignment film as it is. If desired, it may be used after the following rubbing treatment.
On the other hand, when manufacturing a liquid crystal display element other than the VA type, a rubbing treatment is performed on the coating film formed as described above to obtain a liquid crystal alignment film.
The rubbing treatment can be performed by rubbing the coating film surface formed as described above with a roll wound with a cloth made of fibers such as nylon, rayon, and cotton in a certain direction. Thereby, the orientation ability of liquid crystal molecules is imparted to the coating film to form a liquid crystal orientation film.
Further, for the liquid crystal alignment film formed as described above, for example, a liquid crystal as shown in Patent Document 13 (Japanese Patent Laid-Open No. 6-222366) or Patent Document 14 (Japanese Patent Laid-Open No. 6-281937). A process of changing the pretilt angle of a partial region of the liquid crystal alignment film by irradiating a part of the alignment film with ultraviolet rays, or a liquid crystal alignment as disclosed in Patent Document 15 (Japanese Patent Laid-Open No. Hei 5-107544). A resist film is formed on a part of the film surface, then the rubbing process is performed in a direction different from the previous rubbing process, and then the resist film is removed so that the liquid crystal alignment film has different liquid crystal alignment capabilities in each region. It is possible to improve the visual field characteristics of the liquid crystal display element obtained by the above.

(3) A liquid crystal cell is manufactured by preparing two substrates on which a liquid crystal alignment film is formed as described above, and disposing a liquid crystal between the two substrates opposed to each other. Here, when the rubbing process is performed on the coating film, the two substrates are disposed to face each other so that the rubbing directions in the respective coating films are at a predetermined angle, for example, orthogonal or antiparallel.
In order to manufacture a liquid crystal cell, the following two methods are mentioned, for example.
The first method is a conventionally known method. First, two substrates are arranged to face each other through a gap (cell gap) so that the respective liquid crystal alignment films are opposed to each other, and the peripheral portions of the two substrates are bonded using a sealant, and the substrate surface and the sealant are bonded. A liquid crystal cell can be manufactured by injecting and filling liquid crystal into the cell gap partitioned by the step, and then sealing the injection hole.
The second method is a method called an ODF (One Drop Fill) method. For example, an ultraviolet light curable sealing material is applied to a predetermined location on one of the two substrates on which the liquid crystal alignment film is formed, and liquid crystal is dropped on the liquid crystal alignment film surface. The other substrate is bonded so as to face each other, and then the entire surface of the substrate is irradiated with ultraviolet light to cure the sealant, whereby a liquid crystal cell can be manufactured.
Regardless of which method is used, the liquid crystal cell produced as described above is further heated to a temperature at which the liquid crystal used takes an isotropic phase, and then gradually cooled to room temperature, so that the flow alignment during liquid crystal injection is achieved. It is desirable to remove.
And the liquid crystal display element of this invention can be obtained by bonding a polarizing plate on the outer surface of a liquid crystal cell.

Here, as the sealing agent, for example, an epoxy resin containing a curing agent and aluminum oxide spheres as a spacer can be used.
As the liquid crystal, for example, a nematic liquid crystal, a smectic liquid crystal, or the like can be used, and among these, a nematic liquid crystal is preferable. In the case of a VA liquid crystal cell, a nematic liquid crystal having negative dielectric anisotropy is preferable. For example, a dicyanobenzene liquid crystal, a pyridazine liquid crystal, a Schiff base liquid crystal, an azoxy liquid crystal, a biphenyl liquid crystal, or a phenylcyclohexane liquid crystal is used. It is done. In the case of a TN type liquid crystal cell or an STN type liquid crystal cell, a nematic type liquid crystal having positive dielectric anisotropy is preferable. For example, biphenyl type liquid crystal, phenyl cyclohexane type liquid crystal, ester type liquid crystal, terphenyl type liquid crystal, biphenyl cyclohexane type A liquid crystal, a pyrimidine liquid crystal, a dioxane liquid crystal, a bicyclooctane liquid crystal, a cubane liquid crystal, or the like is used. Examples of these liquid crystals include cholesteric liquid crystals such as cholestyl chloride, cholesteryl nonate, and cholesteryl carbonate; chiral agents such as those sold under the trade names C-15 and CB-15 (Merck); Ferroelectric liquid crystals such as -p-amino-2-methylbutyl cinnamate may be further added and used.
As a polarizing plate bonded to the outer surface of the liquid crystal cell, a polarizing film or an H film in which a polarizing film called an “H film” that absorbs iodine while stretching and aligning polyvinyl alcohol is sandwiched between protective films of cellulose acetate The polarizing plate which consists of itself can be mentioned.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.
The ¹ H-NMR of the compounds synthesized in the following synthesis examples, the solution viscosity of the polymer, and the imidization ratio of the polyimide were measured by the following methods, respectively.
[ ¹ H-NMR]
¹ H-NMR of the compound represented by the above formula (A) was measured under the following conditions.
Measuring device: ECX 400P (manufactured by JEOL Ltd.)
Magnetic field strength: 400MHz
Solvent: dimethyl sulfoxide-d ₆
Standard substance: Tetramethylsilane Measurement temperature: 25 ° C
[Solution viscosity of polymer]
The solution viscosity (mPa · s) of the polymer was measured at 25 ° C. using an E-type viscometer for the polymer solution adjusted to a polymer concentration of 10% by weight using the solvent described in each synthesis example. did.
[Imidation rate of polyimide]
A small amount of the polyimide-containing solution obtained in each synthesis example was collected and poured into pure water, and the resulting precipitate was sufficiently dried at room temperature under reduced pressure, then dissolved in deuterated dimethyl sulfoxide, and tetramethylsilane. From the ¹ H-NMR spectrum measured at room temperature using as a reference substance, the following formula (1)
Imidation rate (%) = (1-A ¹ / A ² × α) × 100 (1)
(In Formula (1), A ¹ is a peak area derived from protons of NH groups near a chemical shift of 10 ppm, A ² is a peak area derived from other protons, and α is a polyimide precursor (polyamic acid). (This is the ratio of the number of other protons to one proton of the NH group.)
By calculation.

<Synthesis Example of Compound Represented by Formula (A)>
The synthesis of the following compounds (including intermediates) was repeated on the scale described below as necessary to secure the necessary amount for the synthesis of the following compounds and polymers.
Synthesis Example A-1
Scheme 1 below

Thus, compound (A-1-1) was synthesized.
Under a nitrogen atmosphere, 266.5 g of compound (A-1-1a), 253.3 g of p-chlorobenzenesulfonyl chloride, and 1,000 mL of dichloromethane were charged into a 5,000 mL three-necked flask and stirred at 0 ° C. A solution prepared by dissolving 180 mL of triethylamine in 200 mL of dichloromethane was added dropwise thereto over 30 minutes, and the reaction was performed at room temperature (25 ° C.) with stirring for 3 hours. Next, 1,000 mL of dichloromethane was added to the obtained reaction mixture, and the obtained organic layer was washed with distilled water. The organic layer after washing was dried over magnesium sulfate, and then the solvent was removed by a rotary evaporator to obtain a colorless viscous liquid. After 3,000 mL of ethanol was added to this colorless viscous liquid and sufficiently stirred, the precipitated white solid was collected by filtration to obtain 335.6 g of compound (A-1-1b).
Next, 220.5 g of the above compound (A-1-1b), 166.2 g of ethyl 4-hydroxybenzoate, 172.8 g of potassium carbonate and 2,000 mL of N, N-dimethylformamide are charged into a 5,000 mL three-necked flask. The reaction was conducted at 80 ° C. with stirring for 8 hours. After completion of the reaction, 4,000 mL of toluene was added to the resulting reaction mixture, and the organic layer was washed with distilled water. The organic layer was dried over magnesium sulfate, and then the solvent was removed by a rotary evaporator to obtain a colorless viscous liquid. After adding 3,000 mL of ethanol to the obtained colorless viscous liquid and stirring sufficiently, the precipitated white solid was collected by filtration to obtain 184.1 g of Compound (A-1-1c).
A 5,000 mL three-necked flask was charged with 165.8 g of the above compound (A-1-1c), 40.0 g of sodium hydroxide, 1,500 mL of tetrahydrofuran, 500 mL of distilled water and 500 mL of ethanol, and reacted at 90 ° C. with stirring for 6 hours. Went. After completion of the reaction, 1500 mL of 1N dilute hydrochloric acid was added to the reaction mixture, and the mixture was stirred at room temperature for 1 hour. Subsequently, 2500 mL of toluene was added to the reaction mixture, and the organic layer was washed with distilled water.
Next, the solvent was removed from the organic layer by a rotary evaporator to obtain 154.2 g of a compound (A-1-1d) as a glossy white powder.

Under a nitrogen atmosphere, a 3,000 mL three-necked flask was charged with 116.0 g of the above compound (A-1-1d), 62.0 g of p-toluenesulfonyl chloride, 23 mL of N, N-dimethylformamide and 600 mL of pyridine. Stir for hours. A solution prepared by dissolving 92.4 g of 3,5-bis (diallylamino) phenol (compound (B)) in 150 mL of pyridine was added dropwise thereto over 15 minutes, and then reacted at 100 ° C. with stirring for 6 hours. . After completion of the reaction, 2,000 mL of distilled water was added to the reaction mixture, and extracted with 2,500 mL of chloroform to obtain an organic layer. The obtained organic layer was washed with distilled water and further dried over magnesium sulfate, and then the solvent was removed by a rotary evaporator to obtain a crude product. The obtained crude product was applied to a column chromatograph (filler: silica gel, developing solvent: hexane / ethyl acetate = 20/1 (weight ratio)), and the solvent was removed from the obtained fraction under reduced pressure. The compound (A-1-1e) 103.8g which is a pale yellow viscous liquid was obtained.
Further, 97.9 g of the above compound (A-1-1e), 70.3 g of 1,3-dimethylbarbituric acid, tetrakis (triphenylphosphino) palladium (0) 3. 5 g and 2,000 mL of dichloromethane were charged, and the reaction was performed at 35 ° C. with stirring for 8 hours. After completion of the reaction, the reaction mixture was concentrated to remove about 1 L of dichloromethane, and the precipitated powder was collected by filtration. The resulting glossy pale yellow powder was dissolved in 5,000 mL of tetrahydrofuran, and 60 g of activated carbon was added to the resulting solution and stirred at room temperature for 15 minutes. After removing activated carbon from the obtained mixture by Celite filtration, the solvent was removed under reduced pressure to obtain 55.2 g of compound (A-1-1) as a white powder.
A ¹ H-NMR chart of the obtained compound (A-1-1) is shown in FIG.
Synthesis Example A-2
Scheme 2 below

Thus, compound (A-2-1) was synthesized.
Under a nitrogen atmosphere, in a 5,000 mL three-necked flask, 142.2 g of 3,5-bis (diallylamino) phenol (compound (B)), 220.2 g of ethylene carbonate, 16.1 g of tetrabutylammonium bromide and N, N- 1,000 mL of dimethylformamide was charged, and the reaction was performed at 150 ° C. with stirring for 6 hours. Ethyl acetate (2,000 mL) and methanol (500 mL) were added to the resulting reaction mixture, and the resulting organic layer was washed successively with 1N aqueous sodium hydroxide solution and distilled water, dried over magnesium sulfate, and then on a rotary evaporator. The solvent was removed to give a crude product. The obtained composition organism was applied to a column chromatograph (filler: silica gel, developing solvent: hexane / ethyl acetate = 4/1 (weight ratio)), and the solvent was removed from the obtained fraction under reduced pressure to obtain a light The compound (A-2-1a) 138.6g which is an orange viscous liquid was obtained.
Next, in a 3,000 mL three-necked flask under a nitrogen atmosphere, 154.6 g of the compound (A-1-1d) synthesized in the same manner as in Synthesis Example A-1 above, 76.3 g of p-toluenesulfonyl chloride, N, N-dimethylformamide (32 mL) and pyridine (800 mL) were charged, and the mixture was stirred at 100 ° C. for 1 hour. A solution obtained by dissolving 131.4 g of the compound (A-2-1a) obtained above in 200 mL of pyridine was added dropwise over 15 minutes, and the resulting mixture was reacted at 100 ° C. with stirring for 12 hours. went. After completion of the reaction, 2,000 mL of distilled water was added to the reaction mixture, and extracted with 2,500 mL of chloroform to obtain an organic layer. The obtained organic layer was washed with distilled water and dried over magnesium sulfate, and then the solvent was removed by a rotary evaporator to obtain a crude product. The obtained crude product was applied to a column chromatograph (filler: silica gel, developing solvent: hexane / ethyl acetate = 10/1 (weight ratio)), and the solvent was removed from the obtained fraction under reduced pressure. 178.4 g of compound (A-2-1b) which is a pale yellow viscous liquid was obtained.

Further, in a 5,000 mL three-necked flask under a nitrogen atmosphere, 174.3 g of the above compound (A-2-1b), 117.1 g of 1,3-dimethylbarbituric acid, tetrakis (triphenylphosphino) palladium (0) 5 .8 g and 2,000 mL of dichloromethane were charged, and the reaction was carried out at 35 ° C. with stirring for 8 hours. After completion of the reaction, 2,000 mL of chloroform was added to the reaction mixture, and the organic layer obtained was washed with 1N aqueous sodium carbonate solution to remove unreacted 1,3-dimethylbarbituric acid, and further washed with distilled water. did. The powder obtained by removing the solvent from the organic layer under reduced pressure was thoroughly washed with ethanol. 100 g of activated carbon was added to a solution obtained by dissolving the washed powder (pale yellow) in 2,000 mL of tetrahydrofuran, and the mixture was stirred at room temperature for 15 minutes. The activated carbon was removed from the obtained mixture by Celite filtration, and then the solvent was removed under reduced pressure to obtain 88.6 g of a compound (A-2-1) as a white powder.
A ¹ H-NMR chart of the obtained compound (A-2-1) is shown in FIG.
Synthesis Example A-3
Scheme 3 below

Thus, compound (A-2-2) was synthesized.
Under a nitrogen atmosphere, 238.2 g of compound (A-2-2a), 253.3 g of p-chlorobenzenesulfonyl chloride and 1,000 mL of dichloromethane were charged into a 5,000 mL three-necked flask and stirred at 0 ° C. A solution prepared by dissolving 180 mL of triethylamine in 200 mL of dichloromethane was added dropwise thereto over 30 minutes, and then reacted at room temperature with stirring for 3 hours. After completion of the reaction, 1,000 mL of dichloromethane was added to the obtained reaction mixture, and the organic layer obtained was washed with distilled water, further dried over magnesium sulfate, and then the solvent was removed by a rotary evaporator to obtain a colorless viscous liquid. Obtained. After adding 3,000 mL of ethanol to the obtained colorless viscous liquid and stirring sufficiently, the precipitated white solid was collected by filtration to obtain 318.2 g of compound (A-2-2b).
Subsequently, 206.1 g of the above compound (A-2-2b), 166.2 g of ethyl 4-hydroxybenzoate, 172.8 g of potassium carbonate and 2,000 mL of N, N-dimethylformamide were charged into a 5,000 mL three-necked flask, The reaction was carried out at 80 ° C. with stirring for 8 hours. After completion of the reaction, 4,000 mL of toluene was added to the resulting reaction mixture, and the organic layer obtained was washed with distilled water, further dried over magnesium sulfate, and then the solvent was removed by a rotary evaporator to obtain a colorless viscous liquid. Got. After adding 3,000 mL of ethanol to the obtained colorless viscous liquid and stirring sufficiently, the precipitated white solid was collected by filtration to obtain 174.6 g of compound (A-2-2c).
A 5,000 mL three-necked flask was charged with 154.5 g of the above compound (A-2-2c), 40.0 g of sodium hydroxide, 1,500 mL of tetrahydrofuran, 500 mL of distilled water and 500 mL of ethanol, and reacted at 90 ° C. with stirring for 6 hours. Went. After completion of the reaction, 1,500 mL of 1N dilute hydrochloric acid was added to the resulting reaction mixture, and the mixture was stirred at room temperature for 1 hour. Next, 2,500 mL of toluene was added to the resulting mixture, and the organic layer obtained was washed with distilled water, and then the solvent was removed by a rotary evaporator, whereby the compound (A-2-2d), which was a glossy white powder, was obtained. 142.9 g was obtained.

Under a nitrogen atmosphere, a 3,000 mL three-necked flask was charged with 107.5 g of the above compound (A-2-2d), 62.0 g of p-toluenesulfonyl chloride, 23 mL of N, N-dimethylformamide and 600 mL of pyridine. Stir for hours. A solution prepared by dissolving 106.7 g of the compound (A-2-1a) synthesized in the same manner as in Synthesis Example A-2 in 150 mL of pyridine was added dropwise over 15 minutes, and then stirred at 100 ° C. for 6 hours. The reaction was performed below. After completion of the reaction, 2,000 mL of distilled water was added to the resulting reaction mixture, and further extracted with 2,500 mL of chloroform to obtain an organic layer. The obtained organic layer was washed with distilled water and dried over magnesium sulfate, and then the solvent was removed by a rotary evaporator to obtain a crude product. The obtained crude product was applied to a column chromatograph (filler: silica gel, developing solvent: hexane / ethyl acetate = 20/1 (weight ratio)), and the solvent was removed from the obtained fraction under reduced pressure. Thus, 111.6 g of a compound (A-2-2e) which was a pale yellow viscous liquid was obtained.
Further, in a 5,000 mL three-necked flask under a nitrogen atmosphere, 100.3 g of the above compound (A-2-2e), 70.3 g of 1,3-dimethylbarbituric acid, tetrakis (triphenylphosphino) palladium (0) 3 0.5 g and 2,000 mL of dichloromethane were charged, and the reaction was carried out at 35 ° C. with stirring for 8 hours. After completion of the reaction, the reaction mixture was concentrated to remove about 1,000 mL of dichloromethane, and the precipitated powder was collected by filtration. The obtained glossy light yellow powder was dissolved in 5,000 mL of tetrahydrofuran, and then 60 g of activated carbon was added to the resulting solution and stirred at room temperature for 15 minutes. After removing the activated carbon from the obtained mixture by Celite filtration, the solvent was removed under reduced pressure to obtain 63.0 g of a compound (A-2-2) as a white powder.
A ¹ H-NMR chart of the obtained compound (A-2-2) is shown in FIG.

<Polyimide synthesis example>
Synthesis example PI-1
Obtained in 110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 43 g (0.40 mol) of p-phenylenediamine as diamine and in Synthesis Example A-1. Compound (A-1-1) (49 g, 0.10 mol) was dissolved in N-methyl-2-pyrrolidone (798 g) and reacted at 60 ° C. for 6 hours to obtain a solution containing polyamic acid. A small amount of the obtained polyamic acid solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 62 mPa · s.
Next, 2,000 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 40 g of pyridine and 51 g of acetic anhydride were added, and dehydration ring closure was performed at 110 ° C. for 4 hours. After the dehydration cyclization reaction, the solvent in the system is replaced with new N-methyl-2-pyrrolidone (pyridine and acetic anhydride used in the dehydration cyclization reaction are removed outside the system in this operation. The same applies hereinafter). Thus, a solution containing about 15% by weight of polyimide (B-1) having an imidization ratio of about 50% was obtained. A small amount of the obtained polyimide solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyimide concentration of 10% by weight was 49 mPa · s.

Synthesis example PI-2
66 g (0.30 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5 -Dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione 60 g (0.20 mol) and p-phenylenediamine 38 g (0.35 mol) as diamine and Synthesis Example A -2 (81 g, 0.15 mol) of the compound (A-2-1) obtained in -2 was dissolved in 980 g of N-methyl-2-pyrrolidone and reacted at 60 ° C for 6 hours to obtain a solution containing polyamic acid. It was. A small amount of the obtained polyamic acid solution was collected, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 58 mPa · s.
Next, 2,280 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 40 g of pyridine and 51 g of acetic anhydride were added, and dehydration ring closure was performed at 110 ° C. for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with new N-methyl-2-pyrrolidone to obtain a solution containing about 15% by weight of polyimide (B-2) having an imidization ratio of about 50%. . A small amount of the obtained polyimide solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyimide concentration of 10% by weight was 48 mPa · s.

Synthesis example PI-3
88 g (0.40 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 20 g (0.10 mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride As a diamine, 48 g (0.45 mol) of p-phenylenediamine and 26 g (0.05 mol) of the compound (A-2-2) obtained in Synthesis Example A-3 were dissolved in 728 g of N-methyl-2-pyrrolidone. Then, the reaction was carried out at 60 ° C. for 6 hours to obtain a solution containing polyamic acid. A small amount of the obtained polyamic acid solution was taken, and N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 65 mPa · s.
Next, 1,700 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 40 g of pyridine and 51 g of acetic anhydride were added, and dehydration ring closure was performed at 110 ° C. for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with new N-methyl-2-pyrrolidone to obtain a solution containing about 15% by weight of polyimide (B-3) having an imidization ratio of about 50%. . A small amount of the obtained polyimide solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyimide concentration of 10% by weight was 50 mPa · s.

Synthesis example PI-4
Obtained in 110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 43 g (0.40 mol) of p-phenylenediamine as diamine and in Synthesis Example A-1. Compound (A-1-1) (49 g, 0.10 mol) was dissolved in N-methyl-2-pyrrolidone (798 g) and reacted at 60 ° C. for 4 hours to obtain a solution containing polyamic acid. A small amount of the obtained polyamic acid solution was collected, and N-methyl-2-pyrrolidone was added to measure the solution viscosity as a solution having a polyamic acid concentration of 10% by weight. The solution viscosity was 45 mPa · s.
Next, 2,000 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 80 g of pyridine and 102 g of acetic anhydride were added, and dehydration ring closure was performed at 110 ° C. for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with new N-methyl-2-pyrrolidone to obtain a solution containing about 15% by weight of polyimide (B-4) having an imidization ratio of about 80%. . A small amount of the obtained polyimide solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyimide concentration of 10% by weight was 49 mPa · s.

Synthesis example PI-5
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride, 32 g (0.30 mol) of p-phenylenediamine as diamine, 10 g of 4,4′-diaminodiphenylmethane (0.05 mol) and 81 g (0.15 mol) of the compound (A-2-1) obtained in Synthesis Example A-2 were dissolved in 932 g of N-methyl-2-pyrrolidone and reacted at 60 ° C. for 4 hours. To obtain a solution containing polyamic acid. A small amount of the obtained polyamic acid solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 47 mPa · s.
Next, 2,160 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 80 g of pyridine and 102 g of acetic anhydride were added, and dehydration ring closure was performed at 110 ° C. for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with new N-methyl-2-pyrrolidone to obtain a solution containing about 15% by weight of polyimide (B-5) having an imidization ratio of about 80%. . A small amount of the obtained polyimide solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyimide concentration of 10% by weight was 48 mPa · s.

Synthesis example PI-6
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride, 38 g (0.35 mol) of p-phenylenediamine as diamine, 20 g of 4,4′-diaminodiphenylmethane (0.10 mol) and 26 g (0.05 mol) of the compound (A-2-2) obtained in Synthesis Example A-3 were dissolved in 780 g of N-methyl-2-pyrrolidone and reacted at 60 ° C. for 4 hours. To obtain a solution containing polyamic acid. A small amount of the obtained polyamic acid solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 43 mPa · s.
Next, 1,800 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 80 g of pyridine and 102 g of acetic anhydride were added, and dehydration ring closure was performed at 110 ° C. for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with new N-methyl-2-pyrrolidone to obtain a solution containing about 15% by weight of polyimide (B-6) having an imidization ratio of about 80%. . A small amount of the obtained polyimide solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyimide concentration of 10% by weight was 50 mPa · s.

<Comparative synthesis example of polyimide>
Comparative synthesis example pi-1
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 43 g (0.40 mol) of p-phenylenediamine and 3 (3,5-diaminobenzoyl) as diamine 52 g (0.10 mol) of oxy) cholestane was dissolved in 830 g of N-methyl-2-pyrrolidone and reacted at 60 ° C. for 6 hours to obtain a solution containing polyamic acid. A small amount of the obtained polyamic acid solution was collected, and N-methyl-2-pyrrolidone was added to measure the solution viscosity as a solution having a polyamic acid concentration of 10% by weight of 60 mPa · s.
Next, 1,900 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 40 g of pyridine and 51 g of acetic anhydride were added, and dehydration ring closure was performed at 110 ° C. for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with new N-methyl-2-pyrrolidone to obtain a solution containing about 15% by weight of polyimide (b-1) having an imidization ratio of about 50%. . A small amount of the obtained polyimide solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyimide concentration of 10% by weight was 47 mPa · s.

Comparative synthesis example pi-2
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 43 g (0.40 mol) of p-phenylenediamine and 3 (3,5-diaminobenzoyl) as diamine 52 g (0.10 mol) of oxy) cholestane was dissolved in 830 g of N-methyl-2-pyrrolidone and reacted at 60 ° C. for 4 hours to obtain a solution containing polyamic acid. A small amount of the obtained polyamic acid solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 44 mPa · s.
Next, 1,900 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 80 g of pyridine and 102 g of acetic anhydride were added, and dehydration ring closure was performed at 110 ° C. for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with new N-methyl-2-pyrrolidone to obtain a solution containing about 15% by weight of polyimide (b-2) having an imidization rate of about 80%. . A small amount of the obtained polyimide solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyimide concentration of 10% by weight was 47 mPa · s.

Comparative Synthesis Example pi-3
66 g (0.30 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5 -Dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione 60 g (0.20 mol) and p-phenylenediamine 38 g (0.35 mol) and 3 (3 78 g (0.15 mol) of 5-diaminobenzoyloxy) cholestane was dissolved in 970 g of N-methyl-2-pyrrolidone and reacted at 60 ° C. for 6 hours to obtain a solution containing polyamic acid. A small amount of the obtained polyamic acid solution was collected, and N-methyl-2-pyrrolidone was added to measure the solution viscosity as a solution having a polyamic acid concentration of 10% by weight of 60 mPa · s.
Next, 2,240 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 40 g of pyridine and 51 g of acetic anhydride were added, and dehydration ring closure was performed at 110 ° C. for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with new N-methyl-2-pyrrolidone to obtain a solution containing about 15% by weight of polyimide (b-3) having an imidization ratio of about 50%. . A small amount of the obtained polyimide solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyimide concentration of 10% by weight was 47 mPa · s.

Comparative Synthesis Example pi-4
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride, 32 g (0.30 mol) of p-phenylenediamine as diamine, 10 g of 4,4′-diaminodiphenylmethane (0.05 mol) and 78 g (0.15 mol) of 3 (3,5-diaminobenzoyloxy) cholestane are dissolved in 920 g of N-methyl-2-pyrrolidone and reacted at 60 ° C. for 4 hours to obtain polyamic acid. A solution containing was obtained. A small amount of the obtained polyamic acid solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 44 mPa · s.
Next, 2,140 g of N-methyl-2-pyrrolidone was added to the obtained polyamic acid solution, 80 g of pyridine and 102 g of acetic anhydride were added, and dehydration ring closure was performed at 110 ° C. for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with new N-methyl-2-pyrrolidone to obtain a solution containing about 15% by weight of polyimide (b-4) having an imidization ratio of about 80%. . A small amount of the obtained polyimide solution was taken, N-methyl-2-pyrrolidone was added, and the solution viscosity measured as a solution having a polyimide concentration of 10% by weight was 47 mPa · s.

<Preparation and evaluation of liquid crystal aligning agent>
Example 1
(I) Preparation of liquid crystal aligning agent N-methyl-2-pyrrolidone (NMP) and butyl cellosolve (BC) are added to the solution containing the polyimide (B-1) obtained in Synthesis Example PI-1, and an epoxy compound is further added. N, N, N ′, N′-tetraglycidyl-4,4′-diaminodiphenylmethane is added in an amount of 10 parts by weight to 100 parts by weight of polyimide and sufficiently stirred, and the solvent composition is NMP: BC = 50: 50 ( (Weight ratio) and a solid content concentration of 7.0% by weight. A liquid crystal aligning agent was prepared by filtering this solution using a filter having a pore diameter of 1 μm.
(II) Evaluation of liquid crystal aligning agent The liquid crystal aligning agent prepared above was evaluated by the following method. The evaluation results are shown in Table 1.

(1) Evaluation of applicability (effect of leaving time after application) The liquid crystal aligning agent prepared above is applied to each of the transparent electrode surfaces of five glass substrates with a transparent electrode made of an ITO film. Nissha Printing Co., Ltd.), and the time from the end of application to the start of pre-baking (retention time) is changed to 30 seconds, 60 seconds, 80 seconds, 100 seconds and 120 seconds Then, after heating (prebaking) on a hot plate at 80 ° C. for 1 minute to remove the solvent, heating (post baking) on a hot plate at 230 ° C. for 10 minutes, each having an average film thickness of 600 mm The coating films having different holding times were formed. The coating film was observed with a microscope with a magnification of 20 times for the presence of printing unevenness and pinholes, and the longest holding time in which neither printing unevenness nor pinholes were observed was examined. If this value is 60 seconds or more, it can be said that the coating property is good.
(2) Evaluation of coating film thickness uniformity Among the coating films formed above, the stylus-type film thickness was determined for the coating film formed with the longest holding time in which neither printing unevenness nor pinholes were observed. Using a meter (manufactured by KLA Tencor), the film thickness at the center of the substrate and the film thickness at a position 15 mm away from the outer edge of the substrate were measured, and the difference in film thickness between the two was examined. If this film thickness difference is 20 mm or less, it can be said that the film thickness uniformity is good.

(3) Manufacture of liquid crystal cell The liquid crystal aligning agent prepared above was applied to the transparent electrode surface of the glass substrate with a transparent electrode made of an ITO film using a liquid crystal alignment film printer (Nissha Printing Co., Ltd.). After leaving for 1 minute, the solvent was removed by heating (prebaking) on a hot plate at 80 ° C. for 1 minute, and further heating (post baking) for 10 minutes on a hot plate at 230 ° C. to obtain an average film thickness of 600 mm. A coating film (liquid crystal alignment film) was formed. By repeating this operation, a pair of substrates (two sheets) having a liquid crystal alignment film on the ITO film was obtained.
Next, after applying an epoxy resin adhesive containing aluminum oxide spheres having a diameter of 3.5 μm to the outer edges of the pair of substrates having the liquid crystal alignment film, the liquid crystal alignment film surfaces are overlapped and pressure bonded. The adhesive was cured. Next, after filling nematic liquid crystal (MLC-6608, manufactured by Merck & Co., Inc.) between a pair of substrates from the liquid crystal injection port, the liquid crystal injection port is sealed with an acrylic photo-curing adhesive to produce a liquid crystal cell. did.
(4) Evaluation of voltage holding ratio After applying a voltage of 5 V to the liquid crystal display cell manufactured above at 60 ° C. with an application time of 60 microseconds and a span of 167 milliseconds, 167 milliseconds after release of application The voltage holding ratio (VHR ₀ ) was measured using “VHR-1” manufactured by Toyo Corporation as a measuring device.
(5) Evaluation of heat-resistant stability About the liquid crystal cell manufactured above, a rectangular wave of 30 Hz and 3.0 V on which AC 6.0 V (peak-peak) was superimposed was applied at an environmental temperature of 70 ° C. for 500 hours. The cell voltage holding ratio (VHR ₅₀₀ ) after 500 hours has been measured in the same manner as in the above (4), and this value is compared with the initial value (voltage holding ratio measured in (4) above, VHR ₀ ). The difference between the two (ΔVHR) is expressed by the following formula (2)
ΔVHR (%) = VHR ₀ −VHR ₅₀₀ (2)
We investigated by. When this value was less than 10%, the heat stability was “good”, and when it was 10% or more, the heat stability was evaluated as “bad”.

Examples 2-12, Comparative Examples 1-4
In Example 1 above, each of the solutions containing the polymer described in Table 1 was used instead of the solution containing polyimide (B-1), and the amount of the epoxy compound used was as described in Table 1. A liquid crystal aligning agent was prepared and evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.
In Comparative Examples 2 and 4, since deposition of polyimide was observed when N-methyl-2-pyrrolidone and butyl cellosolve were added to a solution containing polyimide, the liquid crystal aligning agent could not be evaluated. .
Comparative Examples 5 and 6
In Comparative Examples 2 and 4, a liquid crystal aligning agent was prepared in the same manner as in Comparative Examples 2 and 4, except that both solvents were added so that N-methyl-2-pyrrolidone: butyl cellosolve = 70: 30 (weight ratio). Prepared and evaluated.
The evaluation results are shown in Table 1.

Claims (10)

At least one polymer selected from the group consisting of polyamic acid and polyimide, provided that at least a part of the polymer has the following formula (A ′):
_{^{R I - (X I) n1}} -R II -O-X II -COO- (R III O) n2 - * (A ')
(In Formula (A ′), R ^I is an alkyl group having 1 to 30 carbon atoms or a fluoroalkyl group having 1 to 30 carbon atoms, and R ^II is a single bond, a methylene group or an alkylene group having 2 to 30 carbon atoms. R ^III is an alkylene group having 2 to 5 carbon atoms, and X ^I and X ^II are a divalent alicyclic group, a divalent heterocyclic group, an arylene group, or a divalent heteroaromatic group, respectively. A plurality of groups X ^I may be the same or different from each other, n1 is an integer of 2 to 5, n2 is an integer of 0 to 10, and “*” is a bond. (Indicates that
The liquid crystal aligning agent characterized by containing the group represented by these. The polymer is a tetracarboxylic dianhydride and the following formula (A)

(In the formula (A), R ^I , R ^II , R ^III , X ^I , X ^II , n1 and n2 are respectively synonymous with those in the above formula (A ′) .)
It contains at least one polymer selected from the group consisting of a polyamic acid obtained by reacting with a diamine containing a compound represented by formula (I) and a polyimide obtained by dehydrating and ring-closing the polyamic acid . Liquid crystal aligning agent. An X ^I is a divalent alicyclic group in the above formula (A), X ^II is an arylene group, the liquid crystal alignment agent according to claim 2. A xylene group above formula in _^(A) (X _{I) n1} is the ^{4,4'-bicyclo, X II} is a 1,4-phenylene group, liquid crystal aligning agent of claim 3.   The liquid crystal aligning agent as described in any one of Claims 2-4 whose said tetracarboxylic dianhydride contains 2,3,5- tricarboxycyclopentyl acetic acid dianhydride.   A liquid crystal alignment film formed from the liquid crystal alignment agent according to claim 1.   A liquid crystal display element comprising the liquid crystal alignment film according to claim 6.   A polyamic acid obtained by reacting a tetracarboxylic dianhydride with a diamine containing a compound represented by the above formula (A).   A polyimide obtained by dehydrating and ring-closing a polyamic acid obtained by reacting a tetracarboxylic dianhydride with a diamine containing a compound represented by the above formula (A). Compound represented by the above formula (A).

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