KR101530720B1 - Liquid crystal aligning agent, liquid crystal aligning film and liquid crystal display device - Google Patents

Abstract

The present invention relates to a liquid crystal alignment film which exhibits excellent liquid crystal alignment regulating force (pretilt angle manifestation), has improved baking characteristics, and is highly reliable and suppresses accumulation of residual DC voltage after application of thermal stress for a long period of time And to provide a liquid crystal aligning agent capable of providing a liquid crystal alignment agent.

The liquid crystal aligning agent is selected from the group consisting of a polymer having a specific repeating unit represented by the following formula (1-1), a polyamic acid obtained by reacting a tetracarboxylic dianhydride and a diamine, and an imidized polymer thereof At least one polymer.

[Formula 1-1]

A liquid crystal aligning agent, a liquid crystal alignment film, a liquid crystal display element

Description

TECHNICAL FIELD [0001] The present invention relates to a liquid crystal alignment material, a liquid crystal alignment film, and a liquid crystal display device,

The present invention relates to a liquid crystal aligning agent, a liquid crystal alignment film and a liquid crystal display element. More specifically, the present invention relates to a liquid crystal aligning agent which exhibits excellent liquid crystal alignment regulating force (pretilt angle manifestation), a high voltage retention rate, reliability, and a liquid crystal alignment film with suppressed baking after application of thermal stress for a long period of time, And a liquid crystal display element containing the liquid crystal alignment film.

Since the liquid crystal electronic calculator is mass produced for the first time, the liquid crystal display device has been widely used in the fields of watches, portable games, word processors, notebook personal computers, car navigation systems, camcorders, portable information terminals, digital cameras, Various monitors and various monitors are being applied, and active development is continuing.

As a liquid crystal display element, a TN (Twisted Nematic) type liquid crystal display element or a TN type liquid crystal display element in which a long axis of a liquid crystal molecule is twisted by 90 degrees continuously from one substrate toward the other substrate using a nematic liquid crystal, A super twisted nematic (STN) type liquid crystal display device has been widely used. In addition, in order to further improve the display quality of the liquid crystal display, VA (Vertical Alignment) type liquid crystal display elements and IPS (In Plane Switching) type liquid crystal display elements with small viewing angle dependency, And an optically compensated birefringence (OCB) type liquid crystal display device have been developed.

In a liquid crystal display element, a liquid crystal alignment film is used to control alignment of liquid crystal molecules. The liquid crystal alignment film is formed by applying a liquid crystal aligning agent containing an organic resin to a substrate, removing the solvent to form a coating film, and rubbing the coating film in a predetermined direction. Since the liquid crystal alignment layer is a member directly in contact with the liquid crystal molecules, it is known that the electrical characteristics of the liquid crystal alignment layer have a great influence on the baking (accumulation of electric charges) of the liquid crystal panel and the voltage holding ratio. Therefore, it is expected that the improvement of the liquid crystal alignment film will improve the lubrication of the liquid crystal panel. For example, in Patent Documents 1 and 2, there is proposed a technique in which the stored charge is easily diffused (the after-image erasing time is shortened) by changing the composition of the liquid crystal alignment film.

BACKGROUND ART [0002] Recently, liquid crystal display devices have been applied to high-quality monitors, and particularly in the development of liquid crystal television applications. Liquid crystal display devices used for liquid crystal television applications are required to have long-term durability comparable to CRT televisions in addition to clarity of display screen and high response speed. Such long-term durability is not considered from the conventional mode of use of liquid crystal display elements, and the techniques described in the above Patent Documents 1 and 2 are also applicable to the case where the improvement of the small capacity after the application of the thermal stress over a long period at a level required for television applications I do not.

[Patent Document 1] Japanese Unexamined Patent Publication No. 2003-295194

[Patent Document 2] Japanese Patent Application Laid-Open No. 2004-94179

[Patent Document 3] JP-A-2002-327058

[Patent Document 4] JP-A-6-222366

[Patent Document 5] JP-A-6-281937

[Patent Document 6] JP-A-5-107544

SUMMARY OF THE INVENTION The present invention has been made based on the above-described circumstances, and its object is to provide a liquid crystal device which exhibits excellent liquid crystal alignment regulating force (pretilt angle manifestation), has an improved burning property and exhibits high reliability and long- A liquid crystal alignment film capable of providing a liquid crystal alignment film in which the accumulation of a voltage is suppressed, a liquid crystal alignment film having the above-mentioned characteristics, and a liquid crystal display device having excellent resistance to heat after a long thermal stress.

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

According to the present invention, the above objects and advantages of the present invention are achieved by firstly,

A polymer having a repeating unit represented by the following formula (1)

At least one polymer selected from the group consisting of a polyamic acid obtained by reacting a tetracarboxylic acid dianhydride and a diamine and an imidation polymer thereof

And a liquid crystal aligning agent.

(In the formula 1, R ^I is a hydrogen atom or a methyl group, A ¹ represents a single bond, methylene group, alkylene group or a group of a carbon number of 2 to 10, and a divalent group represented by the formula 2, A ¹ is only a bond, a methylene group Or an alkylene group having 2 to 10 carbon atoms, B ¹ is a fluoroalkyl group having 1 to 10 carbon atoms, and A ¹ is a divalent group represented by the following formula (2), B ¹ is an alkyl group having 1 to 10 carbon atoms or an alkyl group having 1 to 10 carbon atoms Lt; / RTI > fluoroalkyl group)

(Wherein n is an integer of 5 to 150)

The above objects and advantages of the present invention are secondly,

And a liquid crystal alignment layer formed of the above-mentioned liquid crystal aligning agent,

The above objects and advantages of the present invention are, thirdly,

And a liquid crystal display element having the above-described liquid crystal alignment film.

According to the present invention, there is provided a liquid crystal alignment film which exhibits excellent liquid crystal alignment regulating force (pretilt angle manifestation), has an improved burning property, and is highly reliable, particularly suppressing accumulation of residual DC voltage after application of thermal stress over a long period of time A liquid crystal alignment film having the above characteristics, and a liquid crystal display element excellent in resistance to insolubility after thermal stress for a long period of time are provided.

Hereinafter, the present invention will be described in detail.

The liquid crystal aligning agent of the present invention comprises a polyamic acid obtained by reacting a polymer having a repeating unit represented by the formula (1) (hereinafter referred to as "polymer (1)") with a tetracarboxylic dianhydride and a diamine, And at least one polymer selected from the group consisting of hydrogenated polymers.

In the divalent group represented by the formula (2) of A ¹ in the formula (1), n is an integer of 5 to 150, but the value is preferably 7 to 15.

Examples of the fluoroalkyl group having 1 to 10 carbon atoms of B ¹ in the formula (1) alkyl, for example trifluoromethyl group, 1,1,2,2-tetrafluoroethoxy group, 1,1,2,2,2- penta A perfluorohexyl group, a perfluorodecyl group, a 2- (perfluorooctyl) ethyl group, and the like can be given.

Specific examples of the repeating unit represented by the formula (1) include, for example, repeating units represented by the following formulas (1-1) to (1-10). Among them, the repeating unit represented by the following formula (1-6) is preferable in that it can provide a liquid crystal alignment film having particularly excellent electric characteristics.

[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

[Formula 1-4]

[Formula 1-5]

[Chemical Formula 1-6]

[Chemical Formula 1-7]

[Chemical Formula 1-8]

[Chemical Formula 1-9]

[Chemical Formula 1-10]

(N in formulas (1-5) and (1-10) are the same as those in formula (2)

The polymer (1) may further contain, in addition to the repeating unit represented by the formula (1), a repeating unit represented by the following formula (3), a repeating unit represented by the following formula (4), a repeating unit represented by the following formula May have at least one repeating unit selected from the group consisting of a repeating unit, a repeating unit represented by the following formula (7), and a repeating unit represented by the following formula (8).

(In the formula 3, R ^II is a hydrogen atom or a methyl group, A ² is a single bond, a methylene group or an alkylene group having 2 to 10 carbon atoms, B ² is giim having a cyclic ether structure of 2 to 10 carbon atoms)

(Wherein R ^III is a hydrogen atom or a methyl group, A ³ is a single bond, a phenylene group or a divalent group represented by any one of the following formulas A 3-1 to A 3-6, B ³ is a carbon number having a steroid skeleton An alkylcyclohexyl group having an alkyl group having 4 to 8 carbon atoms, an alkyl group having 3 to 30 carbon atoms, a difluorophenyl group, a trifluoromethylphenyl group, or a trifluoromethoxyphenyl group)

[Formula (A3-1)

[Formula A3-2]

[Formula A3-3]

[Formula A3-4]

[Formula A3-5]

- (CH ₂ ) _k -O- *

[Formula A3-6]

- (CH ₂ ) _m -COO- *

(A i in the formula are each 0 or 2, j is 0 or 1, and k and m is an integer between 1 and 6, respectively, "*" is the binding of a hand, each attached to a display, combined with B ³ ))

(Wherein R ^IV is a hydrogen atom, a methyl group or a carboxymethyl group, and B ⁴ is a hydrogen atom, a methyl group or a carboxyl group, provided that when R ^IV is a carboxymethyl group, B ⁴ is not a carboxyl group)

(Wherein A ⁵ is a single bond, an oxygen atom or a sulfur atom, or a divalent group containing an oxygen atom, a sulfur atom, a nitrogen atom or a silicon atom, B ⁵ is an aryl group having 6 to 30 carbon atoms, 4 to 10 alicyclic groups)

(And the formula (7) of, R ^V is a hydrogen atom or a methyl group, A ⁶ represents a single bond, or oxygen atom or a sulfur atom, or oxygen atom, a sulfur atom, and 2, comprising a nitrogen atom or a silicon atom monovalent group, B ⁶ is A hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 30 carbon atoms)

(And the formula (8) of, R ^VI is hydrogen or methyl, A ⁷ represents a single bond or -COO - and - (where, "*" is a bond is a display hand attached refers to ⁷ in combination with B), B ⁷ Is an alkylene group having 2 to 10 carbon atoms, an arylene group having 6 to 30 carbon atoms, or a divalent alicyclic group having 4 to 10 carbon atoms)

The cyclic ether structure contained in the repeating unit represented by the above-mentioned general formula (3) is subjected to thermal crosslinking reaction by applying a liquid crystal aligning agent of the present invention to form a coating film and then conducting a heat treatment (post bake) to form a liquid crystal alignment film (Solvent resistance) and film density of the liquid crystal can be further improved, and the diffusion of impurity ions contained in the liquid crystal into the liquid crystal alignment film can be further reduced, and the liquid crystal display element obtained by these effects can exhibit thermal stress A liquid crystal aligning agent which provides a liquid crystal alignment film with a problem that the voltage holding ratio is lowered or the problem of baking is solved more reliably even if the liquid crystal panel is driven for a long time can be obtained. Further, the liquid crystal alignability can be further improved by the repeating unit represented by the formula (4). From this, it is preferable that the polymer (1) has the repeating unit represented by the formula (3) and the repeating unit represented by the formula (4) together with the repeating unit represented by the formula (1).

Accordingly, as the cyclic ether structure of B ² having 2 to 10 carbon atoms in Formula 3, 1,2-epoxy structure or 1,3-epoxy structure having thermal crosslinking reactivity is preferable and 1, A 2-epoxy structure is more preferable. As the repeating unit represented by the formula (3), in the formula (3) is A ² and the resulting repeating units having a methylene group or an alkylene group, B ² is 1,2-epoxy structure with a carbon number of 2 to 10. Preferably, A ² is methylene Group or an alkylene group having 2 or 5 carbon atoms, and B ² is a group having a 1,2-epoxy structure.

The repeating unit represented by the above formula (4) may be included in the polymer (1) to further improve the liquid crystal alignability and electric characteristics of the resulting liquid crystal alignment film. Examples of B ³ in the formula (4) include a monovalent organic group having a carbon number of 17 to 30 having a steroid skeleton, an alkylcyclohexyl group having an alkyl group having a carbon number of 4 to 8, an alkyl group having a carbon number of 3 to 30, a difluorophenyl group, A fluoromethylphenyl group, a trifluoromethoxyphenyl group and the like. Of these, a monovalent organic group having 17 to 30 carbon atoms and a steroid skeleton or an alkylcyclohexyl group having an alkyl group having 4 to 8 carbon atoms is preferable. Examples of the monovalent organic group having a carbon number of 17 to 30 and having a steroid skeleton include a cholestan-3-yl group, a cholesta-5-en-3-yl group, A star-5,24-dien-3-yl group, and a lanostan-3-yl group.

The repeating unit represented by the formula (5) improves the compatibility of the polymer (1) with at least one polymer selected from the group consisting of a polyamic acid and an imidation polymer thereof, and the polymer (1) In the case of having a repeating unit, it may be included in the polymer (1) for the purpose of promoting the crosslinking reaction of the cyclic ether structure.

The repeating unit represented by the formula (6) and the repeating unit represented by the formula (7) may be included in the polymer (1) to further improve the heat resistance of the obtained liquid crystal alignment film.

As A ⁵ in the above formula (6), a single bond is preferable. Examples of the aryl group having 6 to 30 carbon atoms for B ⁵ in the formula (6) include a phenyl group, a naphthyl group, an anthracenyl group, a fluorenyl group and the like; As the alicyclic group having 4 to 10 carbon atoms, for example, a cyclopentyl group, a cyclohexyl group and the like are exemplified, and a phenyl group or a cyclohexyl group is particularly preferable.

As A ⁶ in the general formula (7), a single bond is preferable. Examples of the alkyl group having 1 to 20 carbon atoms represented by B ⁶ in Formula 7 include a methyl group, an ethyl group, a n-propyl group, an n-butyl group, a n-pentyl group, Octyl group and the like; Examples of the aryl group having 6 to 30 carbon atoms include a phenyl group, a 4-biphenyl group, a 2-biphenyl group, a 1-naphthalenyl group and a 2-naphthalenyl group.

The repeating unit represented by the formula (8) may be included in the polymer (1) for the purpose of improving the compatibility of the polymer (1) and at least one polymer selected from the group consisting of a polyamic acid and an imidation polymer thereof.

Examples of the alkylene group having 2 to 10 carbon atoms represented by B ⁷ in the formula (8) include an ethylene group and a 1,4-butylene group; Examples of the arylene group having 6 to 30 carbon atoms include a phenylene group and the like; Examples of the divalent alicyclic group having 4 to 10 carbon atoms include a cyclohexane-1,4-diyl group and the like.

The content of the repeating unit represented by the formula (1) in the polymer (1) is preferably 1% by weight or more, more preferably 1 to 50% by weight, By weight, preferably 1 to 30% by weight, and more preferably 1 to 20% by weight. When the content ratio of the repeating unit represented by the above-described formula (1) is within this range, good electrical characteristics can be imparted to the resulting liquid crystal alignment film.

The content of the repeating unit represented by the above formula (3) is preferably 50% by weight or less, more preferably 5 to 50% by weight, still more preferably 15 to 45% by weight, based on the total weight of the polymer (1) %, Particularly preferably 20 to 40% by weight. By setting the content ratio of the repeating unit represented by the above formula (3) within this range, it is possible to further improve the film density of the obtained liquid crystal alignment film, thereby further reducing the diffusion of the impurity ions contained in the liquid crystal into the liquid crystal alignment film , It is possible to further suppress the baking of the liquid crystal display element.

The content of the repeating unit represented by the general formula (4) is preferably 60% by weight or less, more preferably 1 to 60% by weight, and still more preferably 2 to 40% by weight, based on the total weight of the polymer (1) By weight, particularly preferably 3 to 30% by weight. When the content ratio of the repeating unit represented by the above-mentioned formula (4) is within this range, it is possible to give good pretilt angle manifestation by the resulting liquid crystal alignment film.

The content of the repeating unit represented by the general formula (5) is preferably 50% by weight or less, more preferably 1 to 50% by weight, and still more preferably 1 to 45% by weight, based on the total weight of the polymer (1) By weight, particularly preferably 1 to 40% by weight.

The content of the repeating unit represented by the formula (6) is preferably 20% by weight or less, more preferably 1 to 20% by weight, and still more preferably 1 to 20% by weight, based on the total weight of the polymer (1) 10% by weight.

The content of the repeating unit represented by the general formula (7) is preferably 20% by weight or less, more preferably 1 to 20% by weight, and still more preferably 1 to 10% by weight, based on the total weight of the polymer (1) Weight%.

The content of the repeating unit represented by the formula (8) is preferably 50% by weight or less, more preferably 1 to 50% by weight, and still more preferably 1 to 45% by weight, based on the total weight of the polymer (1) By weight, particularly preferably 1 to 40% by weight.

The polystyrene reduced weight average molecular weight (hereinafter referred to as "Mw") of the polymer (1) measured by gel permeation chromatography (GPC) is preferably from 2 × 10 ³ to 1 × 10 ⁶ , Is 5 x 10 ³ to 5 x 10 ⁵ , particularly preferably 1 x 10 ⁴ to 4 x 10 ⁵ . If the Mw is less than 2 x 10 ^{3, the} problem may arise that the characteristics of the panel deteriorate due to elution of the low-molecular component (decrease in the voltage holding ratio or factor of the panel substrate). On the other hand, if it exceeds 1 × 10 ⁶ , the solution viscosity of the resulting liquid crystal aligning agent becomes excessively high, which may cause problems in coating properties. Further, the molecular weight distribution (hereinafter referred to as "Mw / Mn ", Mn is the number average molecular weight in terms of polystyrene measured by GPC) is preferably 20.0 or less, more preferably 15.0 or less, Or less. By making Mw / Mn small, it is easy to obtain a liquid crystal aligning agent which is excellent in coatability and does not cause problems of deterioration of panel characteristics due to elution of the above-mentioned low molecular components.

The polymer (1) as described above can be obtained, for example, by reacting a compound represented by the following formula (1 ') (hereinafter referred to as "monomer (1' (Hereinafter referred to as "monomer 5 ") (hereinafter referred to as" monomer 5 " (Hereinafter referred to as "monomer (7 ')"), a compound represented by the following formula (6') (hereinafter referred to as "monomer (6 ' (Hereinafter referred to as "monomer (8 ')"), preferably in a suitable solvent in the presence of a suitable polymerization initiator .

≪ Formula (1) >

(Wherein R ¹ , A ^1, and B ¹ are the same as those in Formula 1, respectively)

≪ Formula (3) >

(This is the same meaning as in the formula 3 ', R ^II, A ² and B ² are each the above formula (3))

≪ Formula 4 &

(This is the same meaning as in the formula 4 ', R ^III, A ³ and B ³ is the formula (4) respectively)

≪ Formula 5 &

(In the formula (5 '), R ^IV and B ⁴ are the same as those in the above formula (5), respectively)

(6)

(In the formula (6 '), A ⁵ and B ⁵ are the same as those in the above formula (6)

(7)

(In the formula (7 '), R ^V , A ⁶ and B ⁶ are the same as those in the above formula (7)

≪ Formula 8 >

(Wherein R ^VI , A ⁷ and B ⁷ have the same meanings as in the above formula (8), respectively)

The monomer (1 ') is a monomer for deriving the repeating unit represented by the above formula (1). Specific preferred examples of the monomer (1 ') include acrylic acid-2,2,2-trifluoroethyl acrylate, -3,3,4,4-tetrafluorobutyl acrylate, Acrylic acid (perfluorooctyl) ethyl acrylate, (trifluoromethyl) polydimethylsiloxane, acrylic acid (perfluoroethyl) polydimethylsiloxane, acrylic acid (perfluorooctyl) Polydimethylsiloxane, methacrylic acid-2,2,2-trifluoroethyl, methacrylic acid-3,3,4,4-tetrafluorobutyl, methacrylic acid-3,3,4,4,4- Methacrylic acid (perfluorooctyl) polydimethylsiloxane, methacrylic acid (purple), and the like. Examples of the fluorine-containing polymerizable monomers include, but are not limited to, N-octyldimethylsiloxane), and the like. Among these, from the viewpoint of being able to exhibit excellent electric characteristics, there are acrylic acid-2,2,2-trifluoroethyl, acrylic acid (trifluoromethyl) polydimethylsiloxane, methacrylic acid- Ethyl, methacrylic acid (trifluoromethyl) polydimethylsiloxane, and the like. The term "polydimethylsiloxane" in the above compound is a divalent group represented by the following formula.

(Wherein p is a number of repeating units, preferably an integer of 7 to 15)

The monomer (3 ') is a monomer for deriving the repeating unit represented by the above formula (3), and specific examples thereof include glycidyl acrylate, glycidyl methacrylate, 3,4-epoxybutyl acrylate, methacryl Acrylic acid-6,7-epoxyheptyl, methacrylic acid-6,7-epoxyheptyl,? -Ethylacrylic acid-6,7-epoxyheptyl, and the like. Among them, glycidyl acrylate or glycidyl methacrylate is preferable in that the film thickness of the liquid crystal alignment film obtained is high and reliability of electrical characteristics and electrical characteristics can be exhibited.

The monomer (4 ') is a monomer for deriving the repeating unit represented by the above formula (4). Specific examples of the monomer (4 ') include, for example, cholestanyl methacrylate, 4- (4'-pentylbicyclohexyl-4-yl) phenyl methacrylate and tocopherol methacrylate. Such a monomer (4 ') can be obtained, for example, by reacting a halogenated (meth) acryloyl compound and a compound B ¹ -A ¹ -OH according to a known esterification reaction.

The monomer (5 ') is a monomer which derives the repeating unit represented by the formula (5), and specific examples thereof include maleic acid, fumaric acid, citraconic acid, mesaconic acid, itaconic acid, acrylic acid, methacrylic acid, And the like. Of these, acrylic acid or methacrylic acid is preferable because it is excellent in compatibility between the polymer (1) and the polyamic acid and the imidized polymer thereof, has a high film density of the resulting liquid crystal alignment film, and exhibits high reliability in electrical and electrical properties. desirable.

The monomer (6 ') is a monomer for deriving the repeating unit represented by the formula (6), and specific examples thereof include N-phenylmaleimide, N-naphthylmaleimide, N-anthracenylmaleimide, N-cyclopentylmaleimide, and N-cyclohexylmaleimide. Of these, N-phenylmaleimide or N-cyclohexylmaleimide is preferable.

The monomer (7 ') is a monomer for deriving the repeating unit represented by the above formula (7), and specific examples thereof include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 2-vinylnaphthalene, 2-vinylnaphthalene, and? -Methylstyrene. Of these,? -Olefins such as styrene, Styrene is preferred.

The monomer (8 ') is a monomer for deriving the repeating unit represented by the formula (8), and specific examples thereof include isopropenylphenol, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, 4 -Hydroxybutyl acrylate, 1,4-cyclohexanedimethanol monoacrylate, and the like.

The use ratio (copolymerization ratio) of the monomers (1 ') to (8') in the synthesis of the polymer (1) can be appropriately set according to the composition of the desired polymer (1).

Therefore, the copolymerization ratio of the monomer (1 ') is preferably 1% by weight or more, more preferably 1 to 50% by weight, still more preferably 1 to 30% by weight, based on the total weight of the monomers, Preferably 1 to 20% by weight.

The copolymerization ratio of the monomer (3 ') is preferably 50% by weight or less, more preferably 5 to 50% by weight, still more preferably 15 to 45% by weight based on the total weight of the monomers, Is 20 to 40% by weight.

The copolymerization ratio of the monomer (4 ') is preferably 60% by weight or less, more preferably 1 to 60% by weight, still more preferably 2 to 40% by weight, and particularly preferably 2 to 40% by weight, based on the total weight of the monomers By weight is 3 to 30% by weight.

The copolymerization ratio of the monomers (5 ') is preferably 50% by weight or less, more preferably 1 to 50% by weight, still more preferably 1 to 45% by weight, particularly preferably By weight is from 1 to 40% by weight.

The copolymerization ratio of the monomer (6 ') is preferably 20% by weight or less, more preferably 1 to 20% by weight, and still more preferably 1 to 10% by weight, based on the total weight of the monomers.

The copolymerization ratio of the monomer (7 ') is preferably 20% by weight or less, more preferably 1 to 20% by weight, and still more preferably 1 to 10% by weight, based on the total weight of the monomers.

The copolymerization ratio of the monomer (8 ') is preferably 50% by weight or less, more preferably 1 to 50% by weight, still more preferably 1 to 45% by weight, particularly preferably By weight is from 1 to 40% by weight.

Examples of the solvent used in the synthesis of the polymer (1) include alcohols, ethers, glycol ethers, ethylene glycol alkyl ether acetates, diethylene glycol alkyl ethers, propylene glycol monoalkyl ethers, propylene glycol alkyl ether acetates, propylene glycol alkyl ethers Propionate, aromatic hydrocarbons, ketones, esters and the like.

Specific examples thereof include alcohols such as methanol, ethanol, benzyl alcohol, 2-phenylethyl alcohol, 3-phenyl-1-propanol and the like; Ethers such as tetrahydrofuran, di-n-amyl ether and the like; As the glycol ether, for example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether and the like; As the ethylene glycol alkyl ether acetate, for example, methyl cellosolve acetate, ethyl cellosolve acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monoethyl ether acetate and the like;

As the diethylene glycol alkyl ether, for example, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether and the like; As the propylene glycol monoalkyl ether, for example, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether and the like;

Examples of the propylene glycol alkyl ether propionate include propylene glycol methyl ether propionate, propylene glycol ethyl ether propionate, propylene glycol propyl ether propionate, and propylene glycol butyl ether propionate;

As the propylene glycol alkyl ether acetate, for example, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol propyl ether acetate, propylene glycol butyl ether acetate and the like;

As aromatic hydrocarbons, for example, toluene, xylene and the like;

As the ketone, for example, methyl ethyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone, diisobutyl ketone and the like;

Examples of esters include esters such as methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethyl 2-hydroxypropionate, methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy- Hydroxypropionate, ethyl 3-hydroxypropionate, propyl 3-hydroxypropionate, 3-hydroxypropionate, 3-hydroxypropionate, propyl 3-hydroxypropionate, propyl 3-hydroxypropionate, Propyl propionate, propyl propionate, butyl 2-hydroxy-3-methylbutanoate, methyl methoxyacetate, ethyl methoxyacetate, propyl methoxyacetate, butyl methoxyacetate, ethoxyacetate, ethoxyacetate, ethoxyacetate, Butyl ethoxyacetate, methyl propoxyacetate, ethyl propoxyacetate, propoxyacetic acid propyl, propoxyacetic acid Butyl methoxypropionate, methyl 2-methoxypropionate, ethyl 2-methoxypropionate, propyl 2-methoxypropionate, butyl 2-methoxypropionate, butyl 2-methoxypropionate, Ethoxypropionate, propyl 2-ethoxypropionate, butyl 2-ethoxypropionate, methyl 2-butoxypropionate, ethyl 2-butoxypropionate, propyl 2-butoxypropionate, 2-ethoxypropionate, Methoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, butyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, 3- Ethoxypropionate, butyl 3-ethoxypropionate, methyl 3-propoxypropionate, ethyl 3-propoxypropionate, propyl 3-propoxypropionate, butyl 3-propoxypropionate, 3- Methyl 3-butoxypropionate, ethyl 3-butoxypropionate, propyl 3-butoxypropionate and butyl 3-butoxypropionate.

Among them, ethylene glycol alkyl ether acetate, diethylene glycol alkyl ether, propylene glycol monoalkyl ether and propylene glycol alkyl ether acetate are preferable, and in particular, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, propylene glycol methyl ether, propylene Glycol ethyl ether, propylene glycol methyl ether acetate or methyl 3-methoxypropionate are preferable.

As the polymerization initiator used in the synthesis of the polymer (1), those known as radical polymerization initiators can be used. Azo compounds such as 2,2'-azobisisobutyronitrile, 2,2'-azobis- (2,4-dimethylvaleronitrile), 2,2'-azobis- (4-methoxy- 4-dimethylvaleronitrile); Organic peroxides such as benzoyl peroxide, lauroyl peroxide, t-butyl peroxy pivalate, and 1,1'-bis- (t-butylperoxy) cyclohexane; And hydrogen peroxide. When a peroxide is used as the radical polymerization initiator, the peroxide may be used together with a reducing agent to form a redox type initiator.

In the synthesis of the polymer (1), a molecular weight adjuster may be used to adjust the molecular weight of the polymer (1). Specific examples thereof include halogenated hydrocarbons such as chloroform and carbon tetrabromide; mercaptans such as n-hexylmercaptan, n-octylmercaptan, n-dodecylmercaptan, tert-dodecylmercaptan and thioglycolic acid; Xantogens such as dimethyl xanthogen sulfide and diisopropyl xanthogen disulfide; Terpinolene,? -Methylstyrene dimer, and the like.

In the synthesis of the polymer (1), the polymerization conditions (the type of solvent, the ratio of the solvent and the monomer, the polymerization temperature, the kind of the initiator and the addition amount thereof, the kind of the molecular weight adjuster, . Appropriate polymerization conditions for realizing the above-mentioned molecular weight range can be easily determined by those skilled in the art by carrying out some preliminary experiments.

A polymer solution containing the polymer (1) is obtained as described above. The polymer solution may be used as it is for preparing a liquid crystal aligning agent. Alternatively, the polymer (1) contained in the polymer solution may be isolated and used for the production of a liquid crystal aligning agent, or after the isolated polymer (1) And may be used in the production of an alignment agent. Isolation of the polymer (1) can be carried out by pouring the polymer solution into a large amount of a poor solvent to obtain a precipitate, drying the precipitate under reduced pressure, or a method of distilling off the polymer solution under reduced pressure using an evaporator. Further, the polymer (1) can be purified by a method in which the isolated polymer (1) is dissolved again in an organic solvent, followed by precipitation with a poor solvent, or a step of distillation under reduced pressure using an evaporator once or several times .

<Polyamic acid>

The polyamic acid in the present invention can be obtained by reacting a tetracarboxylic dianhydride with a diamine.

[Tetracarboxylic acid dianhydride]

Examples of the tetracarboxylic acid dianhydride used in the synthesis of the polyamic acid include butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,2-dimethyl- 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,3-dichloro- 3,4-cyclobutane tetracarboxylic acid dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutane tetracarboxylic acid dianhydride, 1,2,3,4-cyclo Pentane tetracarboxylic acid dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3 ', 4,4'-dicyclohexyltetracarboxylic dianhydride, 2,3,5 - tricarboxycyclopentyl acetic acid dianhydride, 3,5,6-tricarboxy norbornane-2-acetic acid dianhydride, 2,3,4,5-tetrahydrofuran tetracarboxylic acid dianhydride, 1,3,3a , 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3- Furanyl) -naphtho [l, 2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro- 3-dione, 1,3,3a, 4,5,9b-hexahydro-5-ethyl-5- (tetra 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 [ , 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2- c] , 1,3,3a, 4,5,9b-hexahydro-8-ethyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [ 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, 5- (2,5-dioxotetrahydrofuranyl) -3-methyl-3-cyclohexene- Tetracarboxylic dianhydride, 3-oxabicyclo [3.2.1] octane-2,4-dicarboxylic acid anhydride, bicyclo [2.2.2] (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene- Dicarboxylic acid anhydride, 3,5,6-tricarboxy- ^2- carboxynorbornane-2: 3,5: 6-dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^{2 , 6} ] undecane-3,5,8,10-tetraone, aliphatic or alicyclic tetracarboxylic acid dianhydride such as compounds represented by the following formulas TI and T-II, respectively;

[Chemical formula I-I]

[Chemical Formula T-II]

(In the formulas TI and T-II, 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, Or may be different)

Pyromellitic dianhydride, 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-biphenylsulfonetetracarboxylic acid dianhydride, 1,4,5 , 8-naphthalene tetracarboxylic acid dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3 ', 4,4'-biphenyl ether tetracarboxylic dianhydride, 3,3 ', 4,4'-dimethyldiphenylsilane tetracarboxylic dianhydride, 3,3', 4,4'-tetraphenylsilane tetracarboxylic dianhydride, 1,2,3,4-furan tetracarboxyl Acid dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylsulfide dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylsulfone dianhydride, 4 , 4'-bis (3,4-dicarboxyphenoxy) diphenylpropane dianhydride, 3,3 ', 4,4'-perfluoroisopropylidene diphthalic acid imumate, 3,3', 4,4 '-Biphenyltetracarboxylic dianhydride, 2,2', 3,3'-biphenyltetracarboxylic dianhydride, bis (phthalic acid) phenylphosphine oxide dianhydride (triphenylphthalic acid) dianhydride, bis (triphenylphthalic acid) -4,4'-diphenyl ether dianhydride, bis (triphenylphthalic acid) dianhydride, m-phenylene- (Anhydrotrimellitate), propylene glycol-bis (anhydrotrimellitate), 1,4-butanediol-bis (anhydroglycidyl) Bis (4-hydroxyphenyl) propane-1,6-hexanediol-bis (anhydrotrimellitate) Bis (anhydrotrimellitate), aromatic tetracarboxylic acid dianhydrides such as compounds represented by the following formulas (T-1) to (T-3), and the like. These may be used singly or in combination of two or more.

[Chemical formula (T-1)

[Chemical Formula T-2]

[Chemical Formula T-3]

Examples of the tetracarboxylic acid dianhydride used in the synthesis of polyamic acid include butane tetracarboxylic acid dianhydride, 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,3-dimethyl- 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,2,3,4-cyclopentanetetracarboxylic acid dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 1,2,3,4- (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 [ 3-dione, 1,3,3a, 4,5,9b-hexahydro-5,8-dimethyl-5- (tetrahydro-2,5-dioxo-3-furanyl) 3-dione, bicyclo [2.2.2] -oct-7-ene-2,3,5,6-tetracarboxylic acid dianhydride, 3-oxabicyclo [3.2.1] Dioxo-2, 4-dione-6-spiro-3 '- (tetrahydrofuran-2', 5'- Furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride, 3,5,6-tricarboxy-2-carboxynorbornane- - dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] undecane-3,5,8,10-tetraone, pyromellitic acid dianhydride, 3,3 ', 4,4'- Benzophenone tetracarboxylic acid dianhydride, 3,3 ', 4,4'-biphenylsulfonetetracarboxylic dianhydride, 2,3', 2,3'-biphenyltetracarboxylic dianhydride, 1, Among the compounds represented by the following formulas T-4 to T-6 and the compounds represented by the above formula (T-II) in the compound represented by the above formula (TI), 4,5,8- -7 (hereinafter referred to as "specific tetracarboxylic dianhydride (1)") from the viewpoint of being able to exhibit good liquid crystal alignability. Particularly preferred specific tetracarboxylic dianhydrides (1) are 2,3,5-tricarboxycyclopentylacetic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl- 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- Furanyl) -naphtho [1,2-c] furan-1,3-dione, 3-oxabicyclo [3.2.1] octane- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride, 3,5,6-tricarboxy-2-carboxynorbornane-2: 3,5: 6-dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] undecane- 8,10-tetraone, and pyromellitic acid dianhydride.

[Chemical Formula T-4]

[Chemical Formula T-5]

[Chemical Formula T-6]

[Chemical Formula T-7]

As the tetracarboxylic acid dianhydride used in the synthesis of polyamic acid, it is preferable that the specific tetracarboxylic dianhydride (1) as described above is contained in an amount of 30 mol% or more based on the total tetracarboxylic acid dianhydride, More preferably 50 mol% or more.

Examples of the diamine used for the synthesis of the polyamic acid include p-phenylenediamine, m-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylethane, 4'-diaminodiphenylsulfide, 4,4'-diaminodiphenylsulfone, 3,3'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diaminobenzanilide, Diaminodiphenyl ether, 1,5-diaminonaphthalene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl , 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl, 3,3'-ditrifluoromethyl-4,4'-diaminobiphenyl, 5-amino- (4'-aminophenyl) -1,3,3-trimethylindane, 3,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, Diaminobenzophenone, 4,4'-diaminobenzophenone, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2 , 2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, Bis (4-aminophenoxy) phenyl] sulfone, 1,4-bis (4-aminophenoxy) benzene, 1 (3-aminophenoxy) benzene, 9,9-bis (4-aminophenyl) -10-hydroanthracene, 2,7-diamino Fluorene, 9,9-dimethyl-2,7-diaminofluorene, 9,9-bis (4-aminophenyl) fluorene, 4,4'- ', 5,5'-tetrachloro-4,4'-diaminobiphenyl, 2,2'-dichloro-4,4'-diamino-5,5'-dimethoxybiphenyl, Dimethoxybiphenyl, 1,4,4 '- (p-phenyleneisopropylidene) bisaniline, 4,4' - (m-phenyleneisopropylidene) bisaniline, 2 , 2'-bis [4- (4-amino-2-trifluoromethylphenoxy) phenyl] hexafluoropropane, 4,4'-diamino-2,2'-bis (trifluoromethyl) Phenyl, and 4,4'-bis [(4-amino-2-trifluoromethyl) phenoxy] -octafluorobiphenyl. Diamine;

Diaminopyridine, 5, 6-diamino-2,3-dicyanopyrimidine, 5, 6-diamino-2,3-dicyanopyrimidine, Dihydroxypyrimidine, 2,4-diamino-6-dimethylamino-1,3,5-triazine, 1,4-bis (3-aminopropyl) piperazine, Diamino-6-isopropoxy-1,3,5-triazine, 2,4-diamino-6-methoxy-1,3,5-triazine, 2,4- 2,4-diamino-6-methyl-s-triazine, 2,4-diamino-1,3,5-triazine, 4,6- Vinyl-s-triazine, 2,4-diamino-5-phenylthiazole, 2,6-diaminopurine, 5,6-diamino-1,3-dimethyluracil, 3,5- Diamino-1,2,4-triazole, 6,9-diamino-2-ethoxy acridactate, 3,8-diamino-6-phenylphenanthridine, Aminophenyl) phenylamine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, N-ethyl- Aminocarbazole, N-phenyl-3,6-diaminocarbazole, N, N'-di (4-aminophenyl) -benzidine, a compound represented by formula DI below, a compound represented by formula D- A diamine having two primary amino groups in the molecule and a nitrogen atom other than the primary amino group;

[Formula D-I]

(In the formula (DI), R ⁵ is a monovalent organic group having a ring structure including a nitrogen atom selected from the group consisting of pyridine, pyrimidine, triazine, piperidine and piperazine, X ¹ is a divalent organic group , R ⁶ is an alkyl group having 1 to 4 carbon atoms, and a 1 is an integer of 0 to 3)

[Formula D-II]

(In the formula (D-II), R ⁷ is a divalent organic group having a ring structure including a nitrogen atom selected from the group consisting of pyridine, pyrimidine, triazine, piperidine and piperazine, and X ² is 2 A plurality of X ^{2 s} present may be the same or different, R ⁸ is each an alkyl group having 1 to 4 carbon atoms, and a 2 is an integer of 0 to 4,

(Aminomethyl) cyclohexane, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, 1,4-diaminocyclo Hexane, isophoronediamine, tetrahydrodicyclopentadienylenediamine, hexahydro-4,7-methanedanilinedimethylenediamine, tricyclo [6.2.1.0 ^2,7 ] -undecylenediimethyldiamine, 4,4'- Aliphatic or alicyclic diamines such as methylenebis (cyclohexylamine);

A diaminoorganosiloxane such as a compound represented by the following formula (D-III), and the like. These diamines may be used alone or in combination of two or more.

[Formula D-III]

(In the formula (D-III), each R ⁹ is a hydrocarbon group of 1 to 12 carbon atoms, plural R ⁹ s present may be the same or different, s is an integer of 1 to 3, and t is an integer of 1 to 20 Integer)

The benzene ring of the aromatic diamine may be substituted with one or more alkyl groups having 1 to 4 carbon atoms (preferably a methyl group). R ⁶ and R ⁸ in the formulas DI and D-II are preferably a methyl group, and a1 and a2 are each preferably 0 or 1, and more preferably 0.

Examples of the diamine used in the synthesis of the polyamic acid in the present invention include p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfide, 1,5 Diaminodiphenyl ether, 9,9-bis (4-aminophenyl) fluorene, 2,2-bis [4- (4- Aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2- 4,4'-diamino-2,2'-bis (trifluoromethyl) biphenyl, 4,4'-bis (4-aminophenoxy) , 4'-diamino-2,2'-dimethylbiphenyl, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminoacrylidine, Among the compounds represented by the above formula (DI), the compound represented by the following formula (D-1), the compound represented by the formula (D-II) (Aminomethyl) cyclohexane, 1,4-cyclohexanediamine, 4,4'-methylenebis (cyclohexylamine), the compound represented by the above formula (D-III) (Tetramethyldisiloxane-1,3-diyl) bis (propylamine), 3,6-diaminocarbazole, N-methyl-3,6-di Is selected from the group consisting of N, N'-di (4-aminophenyl) benzidine, N-ethyl-3,6-diaminocarbazole, N-phenyl- (Hereinafter referred to as "specific diamine") is preferable.

[Formula D-1]

[Formula D-2]

[Formula D-3]

Particularly preferred specific diamines include p-phenylenediamine, 4,4'-diaminodiphenylmethane, 2,7-diaminofluorene, 4,4'-diaminodiphenyl ether, 4,4'-diamino -2,2'-dimethylbiphenyl, and 1,3-bis (aminomethyl) cyclohexane.

The diamine used for the synthesis of the polyamic acid preferably contains 1 mol% or more, more preferably 10 mol% or more, of the specific diamine as described above with respect to the total diamine.

The liquid crystal aligning agent of the present invention can exhibit a desired pretilt angle by adjusting the composition of the polymer (1) and the content of the polymer (1) in the liquid crystal aligning agent to an appropriate range. However, When used in liquid crystal display devices of TN type, STN type, OCB type or VA type, it is preferable to use a diamine having a pretilt angular expression site as a diamine used for synthesis of polyamic acid or its imidized polymer contained in the liquid crystal aligning agent It is also possible to control the pretilt angle of the resulting liquid crystal alignment film.

Examples of the diamine having such a pretilt angle expression site include a compound represented by the following formula (D-IV), a compound represented by the following formula (D-V), and the like. These diamine compounds having these pretilt angle expression sites are used singly or in combination of two or more.

[Formula D-IV]

(In the formula (D-IV), R ¹⁰ and R ¹¹ are each independently a hydrogen atom or a methyl group, R ¹² is a linear or branched alkyl group having 1 to 20 carbon atoms, R ¹³ and R ¹⁴ are each independently Bivalent organic group)

[Chemical formula D-V]

(Wherein R ¹⁵ is an oxygen atom, a sulfur atom, -CO-, -COO-, -OCO-, -NHCO-, -CONH- or a methylene group and R ¹⁶ is a cholestanyl skeleton or a cholesteryl skeleton A monovalent group having a trifluoromethylphenyl group or a trifluoromethoxyphenyl group or an alkyl group having 1 to 22 carbon atoms, R ¹⁷ is an alkyl group having 1 to 4 carbon atoms, and a3 is an integer of 0 to 3)

The monovalent group having a cholestanyl skeleton or cholesteryl skeleton of R ¹⁶ in the above formula (DV) preferably has a carbon number of 17 to 30, and examples thereof include a 3-cholestanyl group and a 3-cholestenyl group. . R ¹⁷ is preferably a methyl group, and a3 is preferably 0 or 1, more preferably 0.

Specific examples of the compound represented by the formula (D-IV) include compounds represented by the following formulas (D-4) and (D-5), respectively; Specific examples of the compound represented by the formula (D-V) include compounds represented by the following formulas (D-6) to (D-10), respectively.

[Formula D-4]

[Formula D-5]

[Formula D-6]

[Formula D-7]

[Formula D-8]

[Chemical formula D-9]

[Formula D-10]

When the liquid crystal aligning agent of the present invention is used in a liquid crystal display device of the VA type, it exhibits excellent vertical alignability of the liquid crystal. Therefore, it is preferable to use the compound represented by the formula (DV) among the diamine compounds having the pretilt angular expression sites , The compounds represented by the above formulas D-6 to D-10 are more preferably used. In particular, the compound represented by the above formula D-6 and the compound represented by the above formula D-7 It is preferable to use at least one of them.

The use ratio of the diamine having a pretilt angle expression site is preferably 8 to 60 mol%, more preferably 9 to 50 mol%, and particularly preferably 10 to 40 mol% based on the total diamine. In this case, the diamine having a pretilt angle expression site may be used in combination with the specific diamine. In this case, the use ratio of the specific diamine is preferably 1 to 90 mol%, more preferably 10 to 20 mol% 90 mol%.

[Synthesis of polyamic acid]

The ratio of the tetracarboxylic dianhydride and the diamine used in the synthesis reaction of the polyamic acid is preferably 0.2 to 2 equivalents of the acid anhydride group of the tetracarboxylic dianhydride with respect to 1 equivalent of the amino group contained in the diamine , More preferably 0.3 to 1.2 equivalents.

The synthesis reaction of the polyamic acid is preferably performed in an organic solvent at a temperature of preferably -20 to 150 ° C, more preferably 0 to 100 ° C. The reaction time is preferably 0.1 to 100 hours, more preferably 1 to 50 hours.

The organic solvent that can be used herein is not particularly limited as long as it can dissolve the polyamic acid to be produced. Examples of the organic solvent include N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, , A non-protonic polar solvent such as dimethyl sulfoxide,? -Butyrolactone, tetramethyl urea, and hexamethylphosphoric triamide; m-cresol, xylenol, phenol, halogenated phenol and the like. The amount (a) of the organic solvent used is preferably such that the total amount (b) of the tetracarboxylic dianhydride and the diamine compound is 0.1 to 30% by weight based on the total amount (a + b) of the reaction solution. Here, when the organic solvent is used in combination with the following poor solvent, the amount (a) of the organic solvent is understood to mean the total amount of the organic solvent and the poor solvent.

The organic solvent may be used in combination with alcohol, ketone, ester, ether, halogenated hydrocarbon, hydrocarbon or the like generally known as a poor solvent for the polyamic acid so long as the produced polyamic acid is not precipitated. Specific examples of such a poor solvent include alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol, cyclohexanol, ethylene glycol, propylene glycol, 1,4-butanediol, triethylene glycol, ethylene glycol monomethyl ether, Butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl acetate, ethyl acetate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, diethyl oxalate, diethyl malonate, diethyl Ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n-propyl ether, ethylene glycol-i-propyl ether, ethylene glycol n-butyl ether, ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, Dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol Recycled monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, tetrahydrofuran, dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, o -Dichlorobenzene, hexane, heptane, octane, benzene, toluene, xylene, isoamyl propionate, isoamyl isobutyrate, and diisopentyl ether.

When the poor solvent as described above is used together with the organic solvent, the ratio of the poor solvent can be appropriately set within a range that the produced polyamic acid does not precipitate, but is preferably 70% by weight or less based on the total amount of the solvent, More preferably not more than 50% by weight.

In this way, a reaction solution obtained by dissolving polyamic acid is obtained. The reaction solution may be used as it is for preparing a liquid crystal aligning agent. Alternatively, the polyamic acid contained in the reaction solution may be isolated and used for the preparation of a liquid crystal aligning agent, or after the isolated polyamic acid is purified, . The isolation of the polyamic acid can be carried out 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 a method of distilling off the reaction solution under reduced pressure using an evaporator. Alternatively, the polyamic acid can be purified by a method of dissolving the polyamic acid in an organic solvent, followed by precipitation with a poor solvent, or a step of distillation under reduced pressure using an evaporator once or several times.

<Imidized Polymer>

The imidized polymer of the polyamic acid in the present invention can be obtained by dehydrating and ring closure of the polyamic acid obtained as described above. The term "imidized polymer" as used herein is a concept including a partially imidized partially imidized polyimic acid and a completely imidized imidated at 100%. These are collectively referred to as "imidized polymer".

[Tetracarboxylic acid dianhydride]

Examples of the tetracarboxylic acid dianhydride used in the synthesis of the imidized polymer include the same compounds as the tetracarboxylic dianhydride used in the synthesis of the polyamic acid described above.

The tetracarboxylic acid dianhydride used in the synthesis of the imidized polymer contained in the liquid crystal aligning agent of the present invention may be at least one selected from the group consisting of alicyclic tetracarboxylic acid dianhydride and pyromellitic dianhydride Tetracarboxylic dianhydride (hereinafter referred to as "specific tetracarboxylic dianhydride (2)").

Particularly preferred specific tetracarboxylic dianhydrides (2) are 2,3,5-tricarboxycyclopentylacetic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro- , 5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro- (Tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 3-oxabicyclo [3.2.1] octane- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene- Dicarboxylic acid anhydride, 3,5,6-tricarboxy- ^2- carboxynorbornane-2: 3,5: 6-dianhydride and 4,9-dioxatricyclo [5.3.1.0 ^{2 , 6} ] undecane-3,5,8,10-tetraone.

As the tetracarboxylic acid dianhydride used in the synthesis of the imidized polymer, the specific tetracarboxylic dianhydride (2) is preferably contained in an amount of 30 mol% or more, more preferably 50 mol% or more, Or more.

[Diamine]

Examples of the diamine used for synthesis of the imidized polymer include the same diamine as the diamine used in the synthesis of the polyamic acid described above.

[Method of synthesizing imidized polymer]

The dehydration ring closure reaction of polyamic acid can be carried out by a method comprising the steps of (i) heating the polyamic acid, (ii) dissolving the polyamic acid in an organic solvent, adding a dehydrating agent and a dehydrating ring- Lt; / RTI &gt;

The reaction temperature in the method of heating the polyamic acid of (i) is preferably 50 to 300 占 폚, more preferably 60 to 170 占 폚. If the reaction temperature is less than 50 ° C, the dehydration ring-closure reaction does not proceed sufficiently, and if the reaction temperature exceeds 300 ° C, the molecular weight of the resulting imidized polymer may be lowered. The reaction time is preferably 2 to 24 hours, more preferably 3 to 10 hours.

On the other hand, in the method of adding the dehydrating agent and dehydrating ring-closing catalyst to the solution of the polyamic acid of the above (ii), for example, an acid anhydride such as acetic anhydride, propionic anhydride or trifluoroacetic anhydride can be used. The amount of the dehydrating agent to be used is preferably 0.01 to 20 mol based on 1 mol of the amic acid structure of the polyamic acid. As the dehydration cyclization catalyst, for example, tertiary amines such as pyridine, collidine, lutidine and triethylamine can be used. However, it is not limited thereto. The amount of the dehydration ring-closing catalyst to be used is preferably 0.01 to 10 mol based on 1 mol of the dehydrating agent to be used. Examples of the organic solvent used in the dehydration ring-closure reaction include organic solvents exemplified for use in 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, and the reaction time is preferably 2 to 8 hours, more preferably 3 to 6 hours.

The imidized polymer obtained in the above method (i) can be directly used for the production of a liquid crystal aligning agent, or after the obtained imidized polymer is purified, it can be used for the production of a liquid crystal aligning agent. On the other hand, in the above method (ii), a reaction solution containing an imidized polymer is obtained. This reaction solution can be used as it is for the preparation of a liquid crystal aligning agent or after the dehydrating agent and the dehydration ring-closing catalyst are removed from the reaction solution, the reaction solution can be used for preparing a liquid crystal aligning agent or after the imidized polymer is isolated, Or may be used in the production of a liquid crystal aligning agent after purification of the isolated imidized polymer. In order to remove the dehydrating agent and the dehydration ring-closing catalyst from the reaction solution, for example, a method such as solvent substitution can be applied. Isolation and purification of the imidized polymer can be performed by carrying out the same operation as described above as a method for isolation and purification of polyamic acid.

Imidation rate of the imidized polymer -

The imidization ratio in the imidized polymer used in the present invention is preferably 10 to 99%, more preferably 20 to 99%, particularly preferably 45 to 99%. Here, the "imidization rate" is a ratio of the number of imide ring structures to the total number of amic acid structures and imide ring structures in the imidized polymer as a percentage. At this time, the number of imidazole rings is also included in the number of imide rings. The imidization rate is determined by dissolving the imidized polymer in a suitable deuterated solvent (for example, deuterated dimethyl sulfoxide), desirably, by using ¹ H-NMR at room temperature using tetramethylsilane as a reference From the measured results, it can be obtained by the following equation (A).

&Lt; EMI ID =

Imidization rate (%) = (1-A ¹ / A ² × α) × 100

A Peak area derived from the proton of the NH group near ¹ : 10 ppm

A ² : Peak area derived from other protons

?: Number of other proton to one proton of NH group in the precursor (polyamic acid) of imidized polymer

- Polymers of terminal modified type -

The polyamic acid and imidized polymer contained in the liquid crystal aligning agent of the present invention may each be a terminal modified type having a controlled molecular weight. By using the polymer of the terminal modified type, the coating property and the like of the liquid crystal aligning agent can be further improved without impairing the effect of the present invention. Such a terminal modified polymer can be produced by adding a molecular weight regulator to a polymerization reaction system when synthesizing a polyamic acid. Examples of the molecular weight regulator include acid monoanhydrides, monoamine compounds, and monoisocyanate compounds.

Examples of the acid anhydride include maleic anhydride, phthalic anhydride, itaconic anhydride, n-decylsuccinic anhydride, n-dodecylsuccinic anhydride, n-tetradecylsuccinic anhydride and n-hexadecylsuccinic anhydride. have. Examples of the monoamine compound include aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, hexadecylamine, n-heptadecylamine, n-octadecylamine, n-octadecylamine, n-octadecylamine, Eicosylamine and the like. Examples of the monoisocyanate compound include phenyl isocyanate and naphthyl isocyanate.

The ratio of the molecular weight regulator to the total diamine used in the synthesis of the polyamic acid in the case of the monoamine compound relative to the total tetracarboxylic acid dianhydride used in the synthesis of the polyamic acid in the case of the monoanhydride, In the case of the monoisocyanate compound, it is preferably 5 mol% or less, more preferably 2 mol% or less, based on the total amount of the tetracarboxylic acid dianhydride used in the synthesis of the polyamic acid.

- solution viscosity -

The polyamic acid or its imidized polymer obtained as described above preferably has a solution viscosity of 500 to 10,000 mPa · s and a solution viscosity of 1,000 to 7,000 mPa · s when the solution is a 20% More preferable.

The solution viscosity (mPa 占 퐏) of the polymer is preferably 20% by weight of a polymer solution prepared by using a good solvent for the polymer (e.g., N-methyl-2-pyrrolidone,? -Butyrolactone, etc.) At 25 ° C using an E-type rotational viscometer.

[Use ratio of polyamic acid and imidized polymer]

The proportion of the at least one polymer selected from the group consisting of polyamic acid and imidized polymer in the liquid crystal aligning agent of the present invention is preferably such that the weight (W ¹ ) of the polymer (1) in the liquid crystal aligning agent and the weight of the polyamic acid and imidized polymer to an amount that is 98 to 80: 20: the ratio of the total weight W ^{1 (W 2): W 2 =} 1: preferably in an amount that is 99 to 90: 10 and, W ^1: W ² = ² And particularly preferably an amount such that W ¹ : W ² = 3: 97 to 60:40.

<Other additives>

The liquid crystal alignment film of the present invention contains at least one selected from the group consisting of the polymer (1) and the polyamic acid and the imidization polymer as described above as an essential component, but may contain other components as required. Examples of such other components include a functional silane compound, a low molecular weight compound having two or more epoxy groups in the molecule (hereinafter referred to as "epoxy compound"), and the like. These functional silane compounds or epoxy compounds can be added to the liquid crystal aligning agent of the present invention in order to further improve the adhesiveness and electrical properties of the obtained liquid crystal alignment film to the substrate surface.

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-ureidopropyltriethoxy Silane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyl triethylenetriamine, N- Trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3 , 6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N- Aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, N-bis (oxyethylene ) -3-aminopropyltrimethoxysilane, and N-bis (oxyethylene) -3-aminopropyltriethoxysilane. When these functional silane compounds are used, the use ratio thereof is preferably 1 to 50 wt% based on 100 wt% of the sum of the polymers (the sum of the polymer (1), polyamic acid and imidized polymer, More preferably 2 to 40 parts by weight, particularly preferably 3 to 20 parts by weight.

The epoxy compound is distinguished from the case where the polymer (1) has a cyclic ether structure, specifically, it has a molecular weight of less than 2,000. Examples of such epoxy compounds 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, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3,5, Tetraglycidyl-2,4-hexanediol, N, N, N ', N'-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl ) Cyclohexane, N, N, N ', N'-tetraglycidyl-4,4'-diaminodiphenylmethane, N, N, N', N'-tetraglycidyl- , N, N-diglycidyl-benzylamine, N, N-diglycidyl-aminomethylcyclohexane, and the like. When these epoxy compounds are used, the use ratio thereof is preferably 1 to 50 parts by weight, more preferably 1 to 30 parts by weight, particularly preferably 1 to 20 parts by weight based on 100 parts by weight of the total amount of the polymers.

<Liquid Crystal Aligner>

The liquid crystal aligning agent of the present invention is preferably at least one selected from the group consisting of the polymer (1), the polyamic acid and the imidized polymer as described above, and other additives optionally blended as required, .

Examples of the organic solvent that can be used in the liquid crystal aligning agent of the present invention include the same solvents as those exemplified for the synthesis reaction of the polymer (1).

Particularly preferable organic solvents used in the liquid crystal aligning agent of the present invention include N-methyl-2-pyrrolidone,? -Butyrolactone,? -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) ethyl 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, Glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl Thermal acetate, and the like can be mentioned isoamyl propionate, isoamyl isobutyrate, di-isopentyl ether. These may be used alone or in combination of two or more.

A particularly preferable solvent composition in the liquid crystal aligning agent of the present invention is a composition obtained by combining the above-described solvents, in which the solid component is not precipitated in the liquid crystal aligning agent and the surface tension of the liquid crystal aligning agent is in the range of 25 to 40 mN / m Composition.

The solid 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 selected in consideration of viscosity, volatility, etc., By weight, more preferably 2 to 40% by weight, and still more preferably 3 to 30% by weight. That is, the liquid crystal aligning agent of the present invention forms a coating film to be a liquid crystal alignment film by coating it on the substrate surface to remove the solvent. When the solid concentration is less than 1 wt%, the film thickness of the coating film becomes too small, It may be difficult to obtain an alignment film. On the other hand, when the solid concentration exceeds 50% by weight, the film thickness of the coating film becomes too large to obtain a good liquid crystal alignment film, the viscosity of the liquid crystal aligning agent is increased and the coating property is lowered, and a liquid crystal alignment film May not be obtained.

Particularly preferable range of the solid concentration is different depending on the coating method used when the liquid crystal aligning agent is applied to the substrate. More specifically, the liquid crystal aligning agent is adjusted to an appropriate solid concentration so as to obtain a solution viscosity suitable for each coating method . For example, in the case of the spinner method, it is preferable to adjust the solution viscosity of the liquid crystal aligning agent in the range of 3.0 to 10.0 mPa.. In the case of the printing method, it is preferable to adjust the solution viscosity of the liquid crystal aligning agent in the range of 12 to 50 mPa.. In the case of the inkjet method, the solution viscosity of the liquid crystal aligning agent is preferably in the range of 3 to 15 mPa.s.

The temperature for producing the liquid crystal aligning agent of the present invention is preferably 0 to 200 占 폚, more preferably 20 to 60 占 폚.

<Liquid crystal display element>

The liquid crystal display element of the present invention comprises a liquid crystal alignment layer formed of 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 method.

(1) First, the liquid crystal alignment film of the present invention is coated on a pair of substrates, and the solvent is removed to form a coating film. Here, when the display mode of the liquid crystal display element to be manufactured is a vertical electric field system such as TN type, STN type or VA type, two substrates on which a transparent conductive film patterned on one side is provided are used as a pair of substrates do. On the other hand, when the display mode of the liquid crystal display element to be manufactured is a transverse electric field system, a substrate provided with a transparent conductive film having a comb-like pattern and a substrate having no transparent conductive film are used as a pair of substrates.

In any of the above cases, the liquid crystal aligning agent is applied on the substrate (on the side having the transparent conductive film of the substrate when the substrate has the transparent conductive film). Examples of the substrate include glass such as float glass and soda glass; A transparent substrate containing plastics such as polyethylene terephthalate, polybutylene terephthalate, polyether sulfone, polycarbonate, and poly (alicyclic olefin) can be used. Examples of the transparent conductive film provided on one side of the substrate include a NESA film (a registered trademark of PPG Corporation of the US) and indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ) containing tin oxide (SnO ₂ ) An ITO film or the like can be used. In order to obtain these patterned transparent conductive films, a method of forming a pattern by a photo-etching method after forming a transparent conductive film without a pattern, a method of using a mask having a desired pattern at the time of forming a transparent conductive film, , A method of directly forming a patterned transparent conductive film, or the like can be used.

The application of the liquid crystal aligning agent on the substrate is carried out by a suitable application method such as a roll coater method, a spinner method, a printing method, and an ink jet method. When applying the liquid crystal aligning agent, a functional silane compound, a functional titanium compound and the like may be previously applied to the surface to be coated of the substrate in order to further improve the adhesion between the substrate surface and the transparent conductive film and the coating film.

After the application, preheating (prebaking) is preferably performed for the purpose of preventing the applied alignment agent from being dropped. The prebaking temperature is preferably 30 to 200 ° C, more preferably 40 to 150 ° C, and particularly preferably 40 to 100 ° C. The prebaking time is preferably 0.5 to 10 minutes, more preferably 0.5 to 5 minutes. Thereafter, a baking (post baking) process is performed for the purpose of completely removing the solvent. Subsequent baking is intended not only to completely remove the solvent from the coating film but also to a method in which the polymer (1) contained in the liquid crystal aligning agent of the present invention has a repeating unit having a cyclic ether structure represented by the above formula (2) , It is also possible to accelerate the thermal crosslinking reaction of the cyclic ether structure. The post baking temperature is preferably 80 to 300 占 폚, more preferably 120 to 250 占 폚. The post-baking time is preferably 5 to 180 minutes, more preferably 10 to 120 minutes.

In this manner, a coating film that becomes a liquid crystal alignment film can be formed. The film thickness of the formed coating film is preferably 0.001 to 1 mu m, more preferably 0.005 to 0.5 mu m.

In the case where the liquid crystal display element to which the liquid crystal aligning agent of the present invention is applied is a liquid crystal display element of VA type, for example, a dried product (see Japanese Patent Application Laid-Open No. 2002-327058) A structure) may be formed on the substrate, and then the liquid crystal aligning agent may be applied to improve the viewing angle characteristics.

(2) When the display mode of the liquid crystal display element to be produced is of the VA type, the coating film formed as described above can be used as the liquid crystal alignment film as it is, but rubbing treatment described below can be performed as necessary. On the other hand, in the case where the display mode of the liquid crystal display element to be manufactured is the vertical electric field system other than VA type or the transverse electric field system, the formed film surface is rubbed.

The rubbing treatment can be carried out by a method of rubbing in a certain direction with a roll of cloth made of fibers such as nylon, rayon, cotton or the like. Accordingly, the alignment ability of the liquid crystal molecules is imparted to the coating film to form a liquid crystal alignment film. Further, the coating film after rubbing treatment can be applied to the coating film as described in, for example, Patent Document 4 (Japanese Patent Application Laid-Open No. 6-222366) and Patent Document 5 (Japanese Patent Application Laid-Open No. 6-281937) A process of changing the pretilt angle of a part of the liquid crystal alignment film by irradiating a part of the same liquid crystal alignment film with ultraviolet rays and a process of changing the pretilt angle of a part of the liquid crystal alignment film surface as described in Patent Document 6 (Japanese Patent Application Laid-open No. 5-107544) The rubbing process is performed in a direction different from the rubbing process performed previously and then the resist film is removed so that the liquid crystal alignment film has a different liquid crystal aligning ability for each region to improve the visual characteristics of the liquid crystal display device It is possible to do.

(3) A liquid crystal cell is prepared by preparing two substrates on which a liquid crystal alignment film is formed as described above, and arranging the liquid crystal between two substrates arranged opposite to each other. Here, when the coating film is subjected to the rubbing treatment, the two substrates are opposed to each other so that the rubbing directions in the respective coating films are made to have a predetermined angle, for example, orthogonal or inversely.

In order to produce a liquid crystal cell, for example, the following two methods can be mentioned.

The first method is a conventionally known method. First, two substrates are opposed to each other through a gap (cell gap) so that the respective liquid crystal alignment films face each other, the peripheral portions of the two substrates are bonded together using a sealing agent, and a cell After the liquid crystal is injected and filled in the interval, the injection hole is sealed to manufacture the liquid crystal cell.

The second method is a method called ODF (One Drop Fill) method. An ultraviolet curable sealing material is applied to a predetermined place on one of the two substrates on which the liquid crystal alignment film is formed and the liquid crystal is dropped on the liquid crystal alignment film surface and then the other substrate is bonded so that the liquid crystal alignment film is opposed And then irradiating ultraviolet light to the entire surface of the substrate to cure the sealing agent, thereby manufacturing a liquid crystal cell.

In any method, it is preferable to heat the liquid crystal used for the liquid crystal cell as described above to a temperature at which the liquid crystal takes an isotropic phase, and then gradually cool to room temperature to remove the flow alignment at the time of filling the liquid crystal.

Further, by bonding a polarizing plate to the outer surface of the liquid crystal cell, the liquid crystal display element of the present invention can be obtained.

As the sealing agent, for example, an epoxy resin containing an aluminum oxide sphere as a curing agent and a spacer can be used.

As the liquid crystal, for example, a nematic liquid crystal and a smectic liquid crystal can be used, and among them, a nematic liquid crystal is preferable. In the VA type liquid crystal cell, a nematic liquid crystal having a negative dielectric anisotropy is preferable. For example, a dicyanobenzene liquid crystal, a pyridazine liquid crystal, a Schiff salt mechanical liquid crystal, an agar liquid crystal, , Phenylcyclohexane-based liquid crystal, and the like. In the case of a TN type liquid crystal cell or an STN type liquid crystal cell, a nematic 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, Phenylcyclohexane-based liquid crystal, pyrimidine-based liquid crystal, dioxane-based liquid crystal, bicyclooctane-based liquid crystal, quartz-based liquid crystal and the like. Examples of the liquid crystal include cholesteric liquid crystals such as cholestyl chloride, cholesteryl nonanoate, and cholesteryl carbonate; Chiral agents sold under the trade names of "C-15" and "CB-15" (manufactured by Merck); and a ferroelectric liquid crystal such as p-disiloxybenzylidene-p-amino-2-methylbutyl cinnamate may be further added.

As the polarizing plate to be bonded to the outer surface of the liquid crystal cell, a polarizing plate in which a polarizing film called "H film " in which iodine is absorbed while polyvinyl alcohol is oriented in a stretched polyvinyl alcohol is sandwiched between cellulose acetate protective films or a polarizing plate made of H film itself can be given.

<Examples>

Hereinafter, the present invention will be described more specifically by way of examples, but the present invention is not limited to these examples.

Measurement of solution viscosity, weight average molecular weight and molecular weight distribution of the polymer in the Examples and Comparative Examples, production of a liquid crystal display element, vertical alignment property of a liquid crystal display element, voltage retention rate and resistance to fading were evaluated by the following methods.

[Measurement of solution viscosity]

The solution viscosity (mPa 占 퐏) of the polymer was measured at 25 占 폚 using an E-type rotational viscometer for the polymer solution specified in each Synthesis Example.

[Measurement of weight average molecular weight and molecular weight distribution]

The weight average molecular weight (Mw) and the number average molecular weight (Mn) in terms of polystyrene were measured using gel permeation chromatography (GPC) under the following conditions to obtain a molecular weight distribution (Mw / Mn) value.

GPC measuring apparatus: "HLC-8020 ", manufactured by Tosoh Corporation,

Column: "TSK guardcolum α", "TSK gel α-M" and "TSK gel α-2500" manufactured by TOSOH CORPORATION are connected in series and used

Solvent: A solution obtained by dissolving 9.4 g of lithium bromide monohydrate and 1.7 g of phosphoric acid in 3 L of dimethylformamide

Measuring temperature: 35 ° C

[Production of liquid crystal display device]

The liquid crystal aligning agent prepared in each of the Examples and Comparative Examples was coated on a transparent conductive film including an ITO film provided on one side of a glass substrate using a spinner and prebaked on a hot plate at 80 DEG C for 1 minute, (In a nitrogen atmosphere) at 200 캜 for one hour to obtain a substrate having a coating film having a film thickness of 60 nm on the transparent conductive film. This substrate was subjected to a rubbing treatment once with a rubbing machine having a roll having a rayon cloth wound thereon at a roll rotation speed of 400 rpm, a stage moving speed of 30 mm / sec, and a hair embroidering length of 0.4 mm, Orientation. Subsequently, this substrate was ultrasonically cleaned in pure water for 1 minute and then dried in a clean oven at 100 DEG C for 10 minutes to obtain a substrate having a liquid crystal alignment film. These operations were repeated to prepare a pair of substrates (two substrates) each having a liquid crystal alignment film.

Next, an epoxy resin adhesive containing aluminum oxide spheres having a diameter of 5.5 占 퐉 was applied to the outer edge portions of each of the surfaces having the liquid crystal alignment film of the substrate having the pair of liquid crystal alignment films, and then the liquid crystal alignment film surface was superposed and pressed, The adhesive was cured.

Subsequently, a negative type liquid crystal (MLC-2038, manufactured by Merck & Co., Inc.) was filled in the gap between the substrates from the liquid crystal injection port, the liquid crystal injection hole was sealed with an acrylic light curing adhesive and a polarizing plate was bonded to both sides of the substrate, Vertical alignment type liquid crystal display device).

[Evaluation of vertical orientation]

The pretilt angle was measured by an anchoring strength measuring apparatus "OMS-J3" manufactured by Juosai Co., Ltd. for the vertically aligned liquid crystal display device manufactured as described above. When the pretilt angle is 87 ° or more, the vertical alignment property is "good". When the pretilt angle is less than 87 °, the vertical alignment property is "poor".

[Evaluation of voltage holding ratio]

A voltage of 5 V was applied to the liquid crystal display device manufactured as described above at a voltage of 60 V for 60 seconds of application time and 1,670 milliseconds of span and then the voltage maintenance rate after 1,670 milliseconds Lt; / RTI &gt; VHR-1 manufactured by Toyo Technica Co., Ltd. was used as a device for measuring the voltage holding ratio. If the value of the voltage holding ratio is 97.5% or more, the voltage holding ratio is "good ", and if it is less than 97.5%

[Reliability test of liquid crystal display element (presence or absence of display defect)]

The liquid crystal display device was driven with a rectangular wave of 5 V and 60 Hz under a high temperature and high humidity environment (temperature 70 캜, relative humidity 80%), and the presence of white speckle display defects after 1,500 hours was observed under a microscope. As a result, reliability was evaluated as "good" when there was no display defect of white speck shape, and reliability "defect"

[Evaluation of resistance to burning (measurement of residual DC voltage, acceleration test)]

A DC voltage of 17 V was applied to the liquid crystal display device manufactured as described above under an atmosphere of 100 DEG C for 20 hours, then the application of the voltage was released and the liquid was allowed to stand for 15 minutes under a room temperature environment. Residual DC voltage) was obtained by the flicker erase method. As the value of the residual DC voltage is smaller, it can be judged that the liquid crystal display element is excellent in long term endurance. A liquid crystal display element having a residual DC voltage value of 200 mV or lower may be referred to as being "good" for internal resistance, and a "internal resistance" for a case where the residual DC voltage value is larger than 200 mV.

Synthesis Example 1 (Synthesis of compound (4 '))

800 g of? -cholestanol was dissolved in 8,000 mL of dehydrated tetrahydrofuran (THF), and 270 g of triethylamine was added thereto. Then, 360 g of methacryloyl chloride was slowly added dropwise, and the mixture was stirred at room temperature for 3 hours . After completion of the reaction, triethylamine hydrochloride was removed by filtration, THF was removed by distillation under reduced pressure, and 4,000 mL of chloroform was added. The resulting solution was washed with water, and the organic layer was dried over magnesium sulfate, and then chloroform was removed by distillation under reduced pressure. Thereafter, recrystallization with ethanol was carried out to obtain 540 g of a white solid colestanyl methacrylate (yield: 57.4%).

Synthesis Example 2 (Synthesis (1) of polymer (1)) [

In a four-necked flask equipped with a stirrer, a three-way cock and a thermometer, 10.0 g (0.0595 mol) of methacrylic acid-2,2,2-trifluoroethyl as a monomer, A mixture of 30.0 g (0.0657 moles) of the reaction product, 25.0 g of glycidyl methacrylate (0.176 moles), 10.0 g of methacrylic acid (0.116 moles), 2.50 g of styrene (0.0240 moles) and 2.50 g of N-cyclohexylmaleimide ) And 20.0 g (0.154 mol) of 2-hydroxyethyl methacrylate were charged. Further, 200 g of diethylene glycol ethyl methyl ether as a solvent and 0.2 g of 2,2'-azobis (2,4-dimethylvalerate Ronitril) and 2.00 g of? -Methylstyrene dimer as a molecular weight regulator. This was bubbled in a nitrogen stream for about 10 minutes to carry out nitrogen substitution in the system, followed by reaction at 70 ° C for 5 hours in a nitrogen atmosphere to obtain a solution containing 33.2% by weight of the polymer (1-1). When the molecular weight of the polymer (1-1) was measured by GPC, Mw = 21,000 and Mw / Mn = 2.3, and no peak due to the residual monomer was observed.

Synthesis Example 3 (Synthesis (2) of polymer (1)) [

5.00 g (0.00940 mol) of methacrylic acid-2- (perfluorooctyl) ethyl methacrylate as a monomer, and 0.5 g of the cholestanyl methacrylate obtained in Synthesis Example 1 were added to a four-necked flask equipped with a stirrer, 25.0 g of glycidyl methacrylate, 0.176 mol of methacrylic acid, 2.50 g of styrene (0.0240 mol), and 2.50 g (0.0139 mol) of N-cyclohexylmaleimide were added to the mixture, And 25.0 g (0.192 mole) of 2-hydroxyethylmethacrylate were charged, and further, 200 g of diethylene glycol ethyl methyl ether as a solvent and 0.2 g of 2,2'-azobis (2,4-dimethylvalero Nitrile) and 2.00 g of? -Methylstyrene dimer as a molecular weight regulator. This was bubbled in a nitrogen stream for about 10 minutes to carry out nitrogen substitution in the system, followed by reaction at 70 ° C for 5 hours in a nitrogen atmosphere to obtain a solution containing 33.5% by weight of the polymer (1-2). When the molecular weight of the polymer (1-2) was measured by GPC, Mw = 16,000 and Mw / Mn = 2.0, and no peak due to the residual monomer was observed.

Synthesis Example 4 (Synthesis (1) of imidized polymer)

112 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic dianhydride as a tetracarboxylic acid dianhydride, 43 g (0.40 mol) of p-phenylenediamine as a diamine and the compound represented by the formula D- 52 g (0.10 mol) was dissolved in 830 g of N-methyl-2-pyrrolidone (NMP), and the reaction was carried out at 60 DEG C for 6 hours to obtain a polyamic acid solution. A small amount of the resulting polyamic acid solution was collected, and NMP was added to measure the viscosity as a solution having a polyamic acid concentration of 10% by weight. The viscosity was 60 mPa.s.

Next, 1,900 g of NMP was added to the obtained polyamic acid solution, and 40 g of pyridine and 51 g of acetic anhydride were added, followed by dehydration ring-closure reaction at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a fresh NMP (pyridine and acetic anhydride used in the dehydration ring closure reaction were removed from the system by this operation, and the same was applied hereinafter), to obtain an imidation polymer having an imidization rate of about 50% PI-1) in an amount of 15 wt%. A small amount of this solution was collected and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight by adding NMP was 47 mPa s.

Synthesis Example 5 (Synthesis (2) of imidized polymer)

112 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride, 38 g (0.35 mol) of p-phenylenediamine as diamine, 4,4'-diaminodiphenyl 20 g (0.10 mol) of methane and 26 g (0.050 mol) of the compound represented by the above formula (D-6) were dissolved in 800 g of NMP and reacted at 60 DEG C for 6 hours to obtain a polyamic acid solution. A small amount of the resulting polyamic acid solution was collected, and NMP was added to measure the viscosity as a solution having a polyamic acid concentration of 10% by weight. The viscosity was 60 mPa.s.

Then, 1,800 g of NMP was added to the obtained polyamic acid solution, 80 g of pyridine and 100 g of acetic anhydride were added, and the dehydration ring-closure reaction was carried out at 110 DEG C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a fresh? -Butyrolactone solvent to obtain about 1,100 g of a solution containing 15% by weight of an imidized polymer (PI-2) having an imidization rate of about 80%. A small amount of this solution was collected and γ-butyrolactone was added to obtain a solution having an imidized polymer concentration of 10 wt%, and the solution viscosity was 87 mPa 揃 s.

Synthesis Example 6 (Synthesis (3) of imidized polymer)

112 g (0.50 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as a tetracarboxylic dianhydride, 43 g (0.40 mol) of p-phenylenediamine as a diamine and the compound represented by the formula D- 49 g (0.10 mol) was dissolved in 820 g of NMP, and the reaction was carried out at 60 DEG C for 6 hours to obtain a polyamic acid solution. A small amount of the resulting polyamic acid solution was collected, and NMP was added to measure the viscosity as a solution having a polyamic acid concentration of 10% by weight. The viscosity was 60 mPa.s.

Next, 1,910 g of NMP was added to the obtained polyamic acid solution, and 40 g of pyridine and 51 g of acetic anhydride were added, followed by dehydration ring-closure reaction at 110 ° C for 4 hours. After the dehydration cyclization reaction, the solvent in the system was replaced with fresh NMP to obtain about 1,200 g of a solution containing 15% by weight of an imidation polymer (PI-3) having an imidization rate of about 50%. A small amount of this solution was collected and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight by adding NMP was 47 mPa s.

Synthesis Example 7 (Synthesis (4) of imidized polymer)

(0.50 mole) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic acid dianhydride, 49 g (0.45 mole) of p-phenylenediamine as diamine and the compound represented by the above formula D-7 Was dissolved in 740 g of NMP, and the reaction was carried out at 60 占 폚 for 6 hours to obtain a polyamic acid solution. A small amount of the resulting polyamic acid solution was collected, and NMP was added to measure the viscosity as a solution having a polyamic acid concentration of 10% by weight. The viscosity was 60 mPa.s.

Next, 1,720 g of NMP was added to the obtained polyamic acid solution, and 40 g of pyridine and 51 g of acetic anhydride were added and the dehydration ring-closure reaction was carried out at 110 DEG C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with fresh NMP to obtain about 1,200 g of a solution containing 15% by weight of an imidized polymer (PI-4) having an imidization rate of about 50%. A small amount of this solution was collected and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight by adding NMP was 47 mPa s.

Synthesis Example 8 (Synthesis (5) of imidized polymer)

(0.50 mole) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic acid dianhydride, 49 g (0.45 mole) of p-phenylenediamine as diamine and the compound represented by the above formula D-7 Was dissolved in 740 g of NMP, and the reaction was carried out at 60 占 폚 for 6 hours to obtain a polyamic acid solution. A small amount of the resulting polyamic acid solution was collected, and NMP was added to measure the viscosity as a solution having a polyamic acid concentration of 10% by weight. The viscosity was 60 mPa.s.

Next, 1,720 g of NMP was added to the obtained polyamic acid solution, 59 g of pyridine and 77 g of acetic anhydride were added, and the dehydration ring-closure reaction was carried out at 110 DEG C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with fresh NMP to obtain about 1,200 g of a solution containing 15% by weight of imidation polymer (PI-5) having an imidization rate of about 65%. A small amount of this solution was collected and the solution viscosity measured as a solution having an imidation polymer concentration of 10% by weight by adding NMP was 67 mPa..

Comparative Synthesis Example 1 (Synthesis of Comparative Polymer)

40 g (0.28 mol) of glycidyl methacrylate, 20 g (0.23 mol) of methacrylic acid, 20 g (0.19 mol) of styrene and 0.1 g of styrene were charged in a four-necked flask equipped with a stirrer, 20 g (0.11 mol) of cyclohexylmaleimide were charged, and further 200 g of diethylene glycol ethyl methyl ether as a solvent, 4.5 g of 2,2'-azobis (2,4-dimethylvaleronitrile) as an initiator and 2.0 g of? -Methylstyrene dimer was added as a molecular weight regulator. This was bubbled in a nitrogen stream for about 10 minutes to carry out nitrogen substitution in the system, and the reaction was carried out at 70 DEG C for 5 hours in a nitrogen atmosphere to obtain a polymer solution containing 33% by weight of Comparative Polymer (R-1) .

When the molecular weight of the polymer (R-1) was measured by GPC, Mw = 22,000 and Mw / Mn = 2.4, and no peak due to the residual monomer was observed.

Example 1

A solution containing the polymer (1-1) obtained in Synthesis Example 2 and a solution containing the imidation polymer (PI-1) obtained in Synthesis Example 4 were mixed with the polymer (1-1): imidation polymer (PI-1 ) Was mixed to give a weight ratio of 5:95. N-methyl-2-pyrrolidone (NMP) and butyl cellosolve were added to the mixture to prepare a solution having a solvent composition of NMP: butyl cellosolve: diethylene glycol ethyl methyl ether = 49.6: 50: 0.4 (weight ratio), and a solid content concentration of 3.5% by weight. This solution was sufficiently stirred, and then filtered using a filter having a pore size of 0.2 탆 to prepare a liquid crystal aligning agent.

Using this liquid crystal aligning agent, evaluation was carried out according to the above-mentioned method. The evaluation results are shown in Table 1.

Example 2

A solution containing the polymer (1-1) obtained in Synthesis Example 2 and a solution containing the imidation polymer (PI-1) obtained in Synthesis Example 4 were mixed with the polymer (1-1): imidation polymer (PI-1 ) Was mixed to give a weight ratio of 5:95, and 10 parts by weight of N, N, N ', N'-tetraglycidyl-m-xylylenediamine as an epoxy compound was added to 100 parts by weight of the total amount of the polymer . NMP and butyl cellosolve were further added thereto to obtain a solution having a solvent composition of NMP: butyl cellosolve: diethylene glycol ethyl methyl ether = 49.6: 50: 0.4 (weight ratio) and a solid concentration of 3.5 wt% . This solution was sufficiently stirred, and then filtered using a filter having a pore size of 0.2 탆 to prepare a liquid crystal aligning agent.

Using this liquid crystal aligning agent, evaluation was carried out according to the above-mentioned method. The evaluation results are shown in Table 1.

Example 3

A solution containing the polymer (1-1) obtained in Synthesis Example 2 and a solution containing the imidized polymer (PI-2) obtained in Synthesis Example 5 were added to the polymer (1-1): imidation polymer (PI-2 ) Was mixed to give a weight ratio of 5:95, and 10 parts by weight of N, N, N ', N'-tetraglycidyl-m-xylylenediamine as an epoxy compound was added to 100 parts by weight of the total amount of the polymer . Butylcellosolve: NMP and butyl cellosolve were further added to the mixture to prepare a solution having a solvent composition of? -Butyrolactone: NMP: butyl cellosolve: diethylene glycol ethyl methyl ether = 40: 29.6: 30: 0.4 (Weight ratio), and a solid content concentration of 3.5% by weight. This solution was sufficiently stirred, and then filtered using a filter having a pore size of 0.2 탆 to prepare a liquid crystal aligning agent.

Using this liquid crystal aligning agent, evaluation was carried out according to the above-mentioned method. The evaluation results are shown in Table 1.

Examples 4 to 7, 9 to 12 and 14 to 16, Comparative Examples 1 and 2

In the same manner as in Example 2, except that a solution containing the polymer shown in Table 1 was used as the polymer solution in Example 2, and the mixing ratios of the polymer and the solvent were changed as shown in Table 1, respectively, Were prepared and evaluated.

The evaluation results are shown in Table 1.

Examples 8 and 13

A liquid crystal aligning agent was prepared and evaluated in the same manner as in Example 3, except that the mixing ratios of the polymer and the solvent were changed as shown in Table 1, respectively.

The evaluation results are shown in Table 1.

Example 17

A liquid crystal aligning agent was prepared in the same manner as in Example 1 except that a solution containing the polymer (1-2) obtained in the above Synthesis Example 3 was used instead of the solution containing the polymer (1-1) Respectively.

The evaluation results are shown in Table 1.

Examples 18 and 20 to 22

A liquid crystal aligning agent was prepared and evaluated in the same manner as in Example 2 except that a solution containing the polymer shown in Table 1 was used as the polymer solution in Example 2 above.

The evaluation results are shown in Table 1.

Example 19

A liquid crystal aligning agent was prepared in the same manner as in Example 3 except that the solution containing the polymer (1-2) obtained in the above Synthesis Example 3 was used instead of the solution containing the polymer (1-1) Respectively.

The evaluation results are shown in Table 1.

Comparative Example 3

NMP and butyl cellosolve were added to the solution containing the imidized polymer (PI-1) obtained in Synthesis Example 4 to dilute it. The solvent composition was NMP: butyl cellosolve = 50: 50 (weight ratio) 3.5% by weight. This solution was sufficiently stirred, and then filtered using a filter having a pore size of 0.2 탆 to prepare a liquid crystal aligning agent.

Using this liquid crystal aligning agent, evaluation was carried out according to the above-mentioned method. The evaluation results are shown in Table 1.

Comparative Example 4

N, N, N ', N'-tetraglycidyl-m-xylylenediamine as an epoxy compound was added to a solution containing the imidized polymer (PI-1) obtained in Synthesis Example 4 in an amount of 5 weight parts And NMP and butyl cellosolve were added thereto to dilute the solution to prepare a solution having a solvent composition of NMP: butyl cellosolve = 50: 50 (weight ratio) and a solid content concentration of 3.5% by weight. This solution was sufficiently stirred, and then filtered using a filter having a pore size of 0.2 탆 to prepare a liquid crystal aligning agent.

Using this liquid crystal aligning agent, evaluation was carried out according to the above-mentioned method. The evaluation results are shown in Table 1.

Comparative Example 5

N, N, N ', N'-tetraglycidyl-m-xylylenediamine as an epoxy compound was added to a solution containing the imidized polymer (PI-5) obtained in Synthesis Example 8 in an amount of 10 wt. Butyllastolactone, NMP and butyl cellosolve were added to the solution to dilute the solution. The solvent composition was γ-butyrolactone: NMP: butyl cellosolve = 40: 30: 30 (weight ratio) To give a solution having a concentration of 3.5% by weight. This solution was sufficiently stirred, and then filtered using a filter having a pore size of 0.2 탆 to prepare a liquid crystal aligning agent.

Using this liquid crystal aligning agent, evaluation was carried out according to the above-mentioned method. The evaluation results are shown in Table 1.

Comparative Examples 6 to 8

In Comparative Example 4, a liquid crystal aligning agent was prepared and evaluated in the same manner as in Comparative Example 4, except that a solution containing the polymer shown in Table 1 was used as the polymer solution.

The evaluation results are shown in Table 1.

The abbreviations in the solvent composition column of Table 1 are as follows.

NMP: N-methyl-2-pyrrolidone

BC: butyl cellosolve (ethylene glycol monobutyl ether)

EDM: diethylene glycol ethyl methyl ether

? -BL:? -butyrolactone

In Table 1, it was found that the liquid crystal alignment layer formed of the liquid crystal aligning agent of the present invention can realize both excellent reliability, high voltage holding ratio and good long-term low-temperature resistance simultaneously (Examples 1 to 12). On the other hand, conventionally known liquid crystal alignment films formed with liquid crystal aligning agents can not simultaneously satisfy all of the above characteristics (Comparative Examples 1 to 8).

The liquid crystal display element of the present invention having the above-described liquid crystal alignment layer exhibits excellent reliability and has an advantage that the accumulation of residual DC at the time of application of thermal stress is suppressed and the baking of the liquid crystal display element is reduced.

Claims (10)

A polymer having a repeating unit represented by the following formula (1) At least one polymer selected from the group consisting of a polyamic acid obtained by reacting a tetracarboxylic acid dianhydride and a diamine and an imidation polymer thereof Wherein the liquid crystal aligning agent is a liquid crystal aligning agent. &Lt; Formula 1 >

(In the formula 1, R ^I is a hydrogen atom or a methyl group, A ¹ represents a single bond, methylene group, alkylene group or a group of a carbon number of 2 to 10, and a divalent group represented by the formula 2, A ¹ is only a bond, a methylene group Or an alkylene group having 2 to 10 carbon atoms, B ¹ is a fluoroalkyl group having 1 to 10 carbon atoms, and A ¹ is a divalent group represented by the following formula (2), B ¹ is an alkyl group having 1 to 10 carbon atoms or an alkyl group having 1 to 10 carbon atoms Lt; / RTI &gt; fluoroalkyl group) (2)

(Wherein n is an integer of 5 to 150) The liquid crystal aligning agent according to claim 1, wherein the polymer having a repeating unit represented by the formula (1) is a polymer having a repeating unit represented by the following formula (3). (3)

(In the formula 3, R ^II is a hydrogen atom or a methyl group, A ² is a single bond, a methylene group or an alkylene group having 2 to 10 carbon atoms, B ² is giim having a cyclic ether structure of 2 to 10 carbon atoms) The liquid crystal aligning agent according to claim 2, wherein B ² in the general formula (3) is a group having a 1,2-epoxy structure or a 1,3-epoxy structure. The liquid crystal aligning agent according to claim 3, wherein A ² in the formula (3) is a methylene group or an alkylene group having 2 to 10 carbon atoms, and B ² is a group having a 1,2-epoxy structure. The liquid crystal aligning agent according to claim 1 or 2, wherein the polymer having a repeating unit represented by the formula (1) is a polymer having a repeating unit represented by the following formula (4). &Lt; Formula 4 >

(Wherein R ^III is a hydrogen atom or a methyl group, A ³ is a single bond, a phenylene group or a divalent group represented by any one of the following formulas A 3-1 to A 3-6, B ³ is a carbon number having a steroid skeleton An alkylcyclohexyl group having an alkyl group having 4 to 8 carbon atoms, an alkyl group having 3 to 30 carbon atoms, a difluorophenyl group, a trifluoromethylphenyl group, or a trifluoromethoxyphenyl group) [Formula (A3-1)

[Formula A3-2]

[Formula A3-3]

[Formula A3-4]

[Formula A3-5] - (CH ₂ ) _k -O- * [Formula A3-6] - (CH ₂ ) _m -COO- * (A i in the formula are each 0 or 2, j is 0 or 1, and k and m is an integer between 1 and 6, respectively, "*" is the binding of a hand, each attached to a display, combined with B ³ ) The liquid crystal aligning agent according to claim 5, wherein B ³ in the general formula (4) is a monovalent organic group having 17 to 30 carbon atoms and having a steroid skeleton. The method according to any one of claims 1 to 4, wherein at least one polymer selected from the group consisting of polyamic acid and imidation polymer thereof is 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 1,2, Cyclobutane tetracarboxylic acid dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic 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- Methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [l, 2-c] furan-l, 3-dione and 3-oxabicyclo [3.2. (Tetrahydrofuran-2 ', 5'-dione), 5- (2,5-dioxotetrahydro-3-furanyl) -3 -Methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride, 3,5,6-tricarboxy-2-carboxynorbornane-2: Oxatricyclo [5.3.1.0 &lt; ^2,6 &gt;] undecane-3,5,8,10-tetraone and pyromellis Tetracarboxylic dianhydride containing at least one member selected from the group consisting of dianhydrides, p-phenylenediamine, 4,4'-diaminodiphenylmethane, 2,7-diaminofluorene, 4,4'-diaminodiphenyl ether, 4,4'-diamino- Diamines including at least one member selected from the group consisting of dimethyl biphenyl and 1,3-bis (aminomethyl) cyclohexane And at least one polymer selected from the group consisting of a polyamic acid and an imidized polymer thereof. The liquid crystal aligning agent according to any one of claims 1 to 4, wherein the diamine comprises a compound represented by the following formula (D-V). [Chemical formula D-V]

(Wherein R ¹⁵ is an oxygen atom, a sulfur atom, -CO-, -COO-, -OCO-, -NHCO-, -CONH- or a methylene group and R ¹⁶ is a cholestanyl skeleton or a cholesteryl skeleton A monovalent group having a trifluoromethylphenyl group or a trifluoromethoxyphenyl group or an alkyl group having 1 to 22 carbon atoms, R ¹⁷ is an alkyl group having 1 to 4 carbon atoms, and a3 is an integer of 0 to 3) A liquid crystal alignment film formed from the liquid crystal aligning agent according to any one of claims 1 to 4. A liquid crystal display element comprising the liquid crystal alignment film according to claim 9.