KR101986398B1 - Liquid crystal aligning agent, liquid crystal alignment membrane, liquid crystal display element, and method for manufacturing liquid crystal display element - Google Patents

Abstract

(식 중 Y₁ 은 2 급 아민, 3 급 아민, 또는, 복소 고리 구조를 갖는 1 가의 유기기를 나타내고, Y₂ 는 2 급 아민, 3 급 아민, 또는, 복소 고리 구조를 갖는 2 가의 유기기를 나타낸다.)(A), (B), (C), and an organic solvent.
(A): a photoreactive side chain comprising a side chain for vertically orienting a liquid crystal and at least one member selected from a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group, And a polyimide obtained by imidizing the polyimide precursor, wherein the polyimide precursor is a polyimide precursor.
Component (B): a polymerizable compound having a group capable of photo-polymerization or photo-crosslinking at one or more terminals.
(C): a diamine having a photoreactive side chain comprising at least one member selected from the group consisting of a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group, A polyimide precursor obtained by the reaction of at least one diamine selected from the following (1) to (C-5) with a tetracarboxylic acid dianhydride, and a polyimide obtained by imidizing the polyimide precursor One kind of polymer.

(Wherein Y ₁ represents a secondary amine, a tertiary amine, or a monovalent organic group having a heterocyclic structure, and Y ₂ represents a secondary amine, a tertiary amine, or a divalent organic group having a heterocyclic structure .)

Description

TECHNICAL FIELD [0001] The present invention relates to a liquid crystal alignment film, a liquid crystal alignment film, a liquid crystal display device, and a manufacturing method of a liquid crystal display device, and more particularly to a liquid crystal alignment device, a liquid crystal alignment membrane, a liquid crystal display element, and a liquid crystal display element.

The present invention relates to a liquid crystal aligning agent, a liquid crystal alignment film, a liquid crystal display element, and a process for producing a liquid crystal display element which can be used for the production of a liquid crystal display device of a vertical alignment type manufactured by irradiating ultraviolet rays while applying a voltage to liquid crystal molecules will be.

Among the liquid crystal display elements of the system (also referred to as a vertical alignment (VA) system) in which the liquid crystal molecules vertically aligned with respect to the substrate are caused to respond by an electric field, a process of irradiating ultraviolet rays while applying a voltage to the liquid crystal molecules .

In such a vertical alignment type liquid crystal display device, a photopolymerizable compound is added in advance to a liquid crystal composition and used together with a vertical alignment film such as polyimide to irradiate ultraviolet light while applying a voltage to the liquid crystal cell, (See, for example, Patent Document 1 and Non-Patent Document 1) are known (Polymer Sustained Alignment (PSA) type liquid crystal display). Generally, the direction in which liquid crystal molecules respond to an electric field is controlled by protrusions formed on a substrate or slits formed on a display electrode, etc. However, when a photopolymerizable compound is added to a liquid crystal composition and ultraviolet rays The polymer structure in which the direction in which the liquid crystal molecules are tilted is formed on the liquid crystal alignment film by irradiation so that the response speed of the liquid crystal display device is faster than the method in which the tilt direction of the liquid crystal molecules is controlled only by the projections or slits It is being referred to.

In this PSA type liquid crystal display element, the solubility of the polymerizable compound to be added to the liquid crystal is low, and there is a problem that precipitation occurs at a low temperature when the addition amount is increased. On the other hand, if the amount of the polymerizable compound to be added is reduced, a favorable alignment state can not be obtained. In addition, since the unreacted polymerizable compound remaining in the liquid crystal becomes an impurity (contamination) in the liquid crystal, there is a problem that the reliability of the liquid crystal display element is lowered. Further, in the UV irradiation process required in the PSA mode, if the irradiation amount is large, the components in the liquid crystal are decomposed to cause a decrease in reliability.

Here, it has been reported that the response speed of a liquid crystal display device is also improved by adding a photopolymerizable compound not in the liquid crystal composition but in a liquid crystal alignment film (SC-PVA type liquid crystal display) (see, for example, Non-Patent Document 2 ).

Japanese Patent Application Laid-Open No. 2003-307720

 K. Hanaoka, SID 04 DIGEST, P. 1200-1202  K. H. Y. -J. Lee, SID 09 DIGEST, P. 666-668

However, it is desired to further increase the response speed of the liquid crystal display element. It is also conceivable to increase the response speed of the liquid crystal display element by increasing the addition amount of the photopolymerizable compound. However, when this photopolymerizable compound remains in the liquid crystal in an unreacted state, it becomes an impurity and the reliability of the liquid crystal display element is improved It is preferable to use a polymerizable compound capable of accelerating the response speed with a small addition amount.

 It is also desired to improve the electric characteristics of the resulting liquid crystal display element, in particular to improve the DC charge storage characteristics.

SUMMARY OF THE INVENTION The object of the present invention is to solve the problems of the above-described prior arts, and it is an object of the present invention to provide a liquid crystal display device capable of improving the response speed of a liquid crystal display element of a vertical alignment system, A liquid crystal alignment film, a liquid crystal display element, and a method of manufacturing a liquid crystal display element.

As a result of intensive studies to solve the above problems, the inventors of the present invention have found that a liquid crystal composition comprising a side chain that vertically aligns a liquid crystal and at least a side chain selected from the group consisting of methacryl group, acrylic group, vinyl group, allyl group, coumarin group, styryl group, A polyimide precursor having a photoreactive side chain containing one species and a polyimide obtained by imidizing the polyimide precursor are mixed with a mixture of a diamine having a photoreactive side chain and a diamine having a predetermined structure The above problems can be solved by mixing (blending) a polyimide precursor and a polymer selected from polyimide obtained by imidizing the polyimide precursor.

That is, the present invention has the following points.

1. A liquid crystal aligning agent which comprises the following components (A), (B), (C) and an organic solvent.

(A): a photoreactive side chain comprising a side chain for vertically orienting a liquid crystal and at least one member selected from a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group, And a polyimide obtained by imidizing the polyimide precursor, wherein the polyimide precursor is a polyimide precursor.

Component (B): a polymerizable compound having a group capable of photo-polymerization or photo-crosslinking at one or more terminals.

(C): a diamine having a photoreactive side chain comprising at least one member selected from the group consisting of a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group, A polyimide precursor obtained by the reaction of at least one diamine selected from the following (1) to (C-5) with a tetracarboxylic acid dianhydride, and a polymer selected from polyimides obtained by imidizing the polyimide precursor .

[Chemical Formula 1]

(Wherein Y ₁ represents a secondary amine, a tertiary amine, or a monovalent organic group having a heterocyclic structure, and Y ₂ represents a secondary amine, a tertiary amine, or a divalent organic group having a heterocyclic structure .)

2. The liquid crystal aligning agent according to 1, characterized in that the photoreactive side chain comprises a group selected from the following formula (I).

(2)

(Wherein R < ¹¹ > is H or a methyl group)

3. The liquid crystal aligning agent according to 1 or 2, wherein the photopolymerization or photo-crosslinking group is selected from the following formula (II).

(3)

(Wherein R ¹² is H or an alkyl group having 1 to 4 carbon atoms, Z ¹ is a bivalent aromatic ring or heterocyclic ring optionally substituted by an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms, and Z ² is a monovalent aromatic ring or heterocyclic ring which may be substituted with an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms.

4. The polyimide resin composition according to claim 1, wherein the component (C) is a polyamine obtained by using diamines selected from the formulas (C-1) to (C-5) in an amount of 10 mol% to 80 mol% A liquid crystal aligning agent according to any one of 1 to 3, wherein the liquid crystal aligning agent is a polymer selected from the group consisting of a polyimide precursor and a polyimide obtained by imidizing the polyimide precursor.

5. A liquid crystal alignment film obtained by applying a liquid crystal aligning agent described in any one of 1 to 4 on a substrate and firing.

6. A liquid crystal cell produced by applying a liquid crystal aligning agent described in any one of 1 to 4 to a substrate to form a liquid crystal layer in contact with a liquid crystal alignment film obtained by firing and irradiating ultraviolet rays while applying a voltage to the liquid crystal layer, And the liquid crystal display element.

7. A method for producing a liquid crystal cell, which comprises applying a liquid crystal aligning agent described in any one of 1 to 4 to a substrate to form a liquid crystal layer in contact with a liquid crystal alignment film obtained by firing and irradiating ultraviolet rays while applying a voltage to the liquid crystal layer Wherein the liquid crystal display element is a liquid crystal display element.

According to the present invention, it is possible to provide a liquid crystal display element of a vertical alignment system in which the response speed of liquid crystal is fast and the accumulation of direct current charge is small. In this liquid crystal aligning agent, even when the amount of the polymerizable compound to be added is small, the response speed can be sufficiently improved.

Hereinafter, the present invention will be described in detail.

The liquid crystal aligning agent of the present invention is a liquid crystal aligning agent containing the components (A), (B), (C) and an organic solvent. The liquid crystal aligning agent is a solution for preparing a liquid crystal alignment film, and the liquid crystal alignment film is a film for orienting the liquid crystal in a predetermined direction, in the present invention, in the vertical direction. Each component contained in the liquid crystal aligning agent of the present invention will be described in detail below.

[Component (A)] [

The liquid crystal aligning agent of the present invention comprises, as the component (A), a side chain which vertically aligns a liquid crystal and at least a side chain selected from the group consisting of a methacryl group, an acryl group, a vinyl group, an allyl group, a coumarin group, a styryl group, At least one polymer selected from a polyimide precursor having a photoreactive side chain containing one species and a polyimide obtained by imidizing the polyimide precursor. Examples of the polyimide precursor include polyamic acid (also referred to as polyamic acid), polyamic acid ester, and the like.

<Side Chain for Vertically Orienting Liquid Crystal>

The side chain for orienting the liquid crystal vertically is not limited as long as the liquid crystal can be oriented perpendicular to the substrate. For example, the side chain may be a long chain alkyl group, a group having a ring structure or a branch structure in the middle of the long chain alkyl group, A steroid group, a group in which a part or all of the hydrogen atoms of these groups are substituted with a fluorine atom, and the like. The side chains for orienting the liquid crystal vertically may be directly bonded to the main chain of the polyimide precursor or polyimide such as polyamic acid, or may be bonded via a suitable bonding group. Examples of the side chain for vertically orienting the liquid crystal include those represented by the following formula (a).

[Chemical Formula 4]

(In the formula (a), l, m and n each independently represent an integer of 0 or 1, and R ³ represents an alkylene group having 2 to 6 carbon atoms, -O-, -COO-, -OCO-, -NHCO-, -CONH- or an alkylene-ether group having 1 to 3 carbon atoms; R ⁴ , R ⁵ and R ⁶ each independently represent a phenylene group or a cycloalkylene group; R ⁷ represents a hydrogen atom, an alkyl group having 2 to 24 carbon atoms Or a fluorine-containing alkyl group, a monovalent aromatic ring, a monovalent aliphatic ring, a monovalent heterocyclic ring, or a monovalent macrocyclic substituent thereof.

R ³ in the formula (a) is preferably -O-, -COO-, -CONH-, or an alkylene-ether group having 1 to 3 carbon atoms, from the viewpoint of ease of synthesis.

R ⁴ , R ⁵ and R ⁶ in the formula (a) are preferably 1, m, n, R ⁴ , R ⁵ and R ⁶ shown in the following Table 1 from the viewpoints of ease of synthesis and ability to orient the liquid crystal vertically ⁶ is preferable.

When at least one of l, m and n is 1, R ⁷ in the formula (a) is preferably a hydrogen atom or an alkyl group having 2 to 14 carbon atoms or a fluorine-containing alkyl group, more preferably a hydrogen atom or a carbon number An alkyl group having 2 to 12 carbon atoms or a fluorine-containing alkyl group. In addition, l, m, and when n is 0, together, R ⁷ is preferably constituted by an alkyl group or a fluorine-containing alkyl group, a monovalent aromatic ring, a monovalent aliphatic cyclic, monovalent heterocyclic ring, those having a carbon number of 12 to 22 , More preferably an alkyl group having 12 to 20 carbon atoms or a fluorine-containing alkyl group.

The amount of the side chain that vertically aligns the liquid crystal is not particularly limited as long as the liquid crystal alignment film can orient the liquid crystal vertically. However, in the liquid crystal display device having the liquid crystal alignment film, the abundance of the side chains for vertically orienting the liquid crystal is preferably within a range that does not inhibit the display characteristics of the device, such as the voltage holding ratio and the accumulation of the residual DC voltage The smaller is preferable.

The ability of a polymer having a side chain to vertically align liquid crystals to orient liquid crystals vertically differs depending on the structure of side chains that vertically align liquid crystals, but generally, a side chain As the amount increases, the ability to align the liquid crystal vertically increases, and when it decreases, it decreases. Further, in the case of having a cyclic structure, the ability of vertically aligning the liquid crystal tends to be higher as compared with the case where the cyclic structure is not provided.

<Photoreactive side chain>

The photoreactive side chain is a side chain having a functional group capable of forming a covalent bond by reaction with ultraviolet light (hereinafter, also referred to as a photoreactive group). In the present invention, as the photoreactive group, a methacryloxy group , An acryl group, a vinyl group, an allyl group, a coumarin group, a styryl group, and a cinnamoyl group. As described above, it is preferable that the polymer comprising at least one kind of polyimide precursor and polyimide contained in the liquid crystal aligning agent is at least one selected from the group consisting of methacrylic group, acrylic group, vinyl group, allyl group, coumarin group, styryl group and cinnamoyl group Reactive side chain including one kind of the polymerizable compound and the component (B) as the polymerizable compound in the liquid crystal aligning agent, the response speed can be remarkably improved as shown in Examples described later.

The photoreactive side chain may be directly bonded to the main chain of the polyimide precursor or polyimide, or may be bonded via a suitable bonding group. The photoreactive side chain includes, for example, those represented by the following formula (b).

[Chemical Formula 5]

(In the formula (b), R ⁸ represents a single bond or -CH ₂ -, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH 2 O-, -N (CH 3) -, -CON (CH 3) -, -N (CH 3) any of the CO- And R ⁹ represents a single bond or an alkylene group having 1 to 20 carbon atoms which is substituted by an unsubstituted or fluorine atom, and -CH ₂ - of the alkylene group is optionally substituted with -CF ₂ - or -CH═CH-, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -NHCO-, -NHCO-, -NHCO-, -NHCO-, -, a divalent carbon ring, a divalent heterocyclic ring. R ¹⁰ represents a methacryl group, an acryl group, a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group.

R ⁸ in the above formula (b) can be formed by a common organic synthetic method, but from the viewpoint of ease of synthesis, -CH ₂ -, -O-, -COO-, -NHCO-, -NH -, -CH ₂ O-.

Specific examples of the carbon ring group and the heterocyclic ring of the divalent carbon ring group or the divalent heterocyclic ring substituting any -CH ₂ - in R ⁹ include, but are not limited to, the following structures .

[Chemical Formula 6]

R ¹⁰ is preferably a methacryl group, an acrylic group or a vinyl group from the viewpoint of photoreactivity.

 The above formula (b) is more preferably a structure containing a group selected from the above formula (I).

The abundance of the photoreactive side chain is preferably within a range capable of accelerating the response speed of the liquid crystal by reacting with ultraviolet light to form a covalent bond and in order to accelerate the response speed of the liquid crystal, It is preferable that the number is as large as possible within a range that does not cause a problem.

&Lt; Production method of component (A) &gt;

A polyisocyanate having a photoreactive side chain containing at least one kind selected from a side chain for vertically orienting the liquid crystal and a methacrylic group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group, The method for producing the component (A), which is at least one kind of polymer selected from a polyimide precursor and a polyimide obtained by imidizing the polyimide precursor, is not particularly limited, and examples thereof include a method in which a diamine and a tetracarboxylic acid 2 There is provided a method for producing a polyamic acid by reaction of an anhydride, which comprises reacting a diamine having a side chain that vertically aligns the liquid crystal or a tetracarboxylic acid dianhydride having a side chain that vertically aligns the liquid crystal, a methacrylic group, A diamine having a photoreactive side chain including at least one selected from a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group, or A tetracarboxylic acid dianhydride having a photoreactive side chain containing at least one member selected from the group consisting of methacrylic groups, acrylic groups, vinyl groups, allyl groups, coumarin groups, styryl groups and cinnamoyl groups may be copolymerized.

Examples of the diamine having a side chain that vertically aligns the liquid crystal include a long-chain alkyl group, a group having a ring structure or branched structure in the middle of the long-chain alkyl group, a steroid group, or a group in which some or all of hydrogen atoms in these groups are substituted with a fluorine atom And a diamine having a side chain, for example, a diamine having a side chain represented by the above formula (a). More specifically, examples thereof include diamines represented by the following formulas (2), (3), (4) and (5), but the present invention is not limited thereto.

(7)

(The definitions of 1, m, n and R ³ to R ⁷ in the formula (2) are the same as those of the formula (a).)

[Chemical Formula 8]

(In the formulas (3) and (4), A ₁₀ represents -COO-, -OCO-, -CONH-, -NHCO-, -CH ₂ -, -O-, -CO- or -NH- , A ₁₁ represents a monovalent bond or a phenylene group, a represents the same structure as the side chain for vertically orienting the liquid crystal represented by the formula (a), and a 'represents the liquid crystal represented by the formula (a) Represents a divalent group having a structure in which one element such as hydrogen is missing from the same structure as the side chain to be subjected to the reaction.

[Chemical Formula 9]

(In the formula (5), A ₁₄ is an alkyl group having 3 to 20 carbon atoms which may be substituted with a fluorine atom, A ₁₅ is a 1,4-cyclohexylene group or a 1,4-phenylene group, A ₁₆ is an oxygen atom Or -COO- * (provided that a bonding hand having "*" is bonded to A ₁₅ ), A ₁₇ is an oxygen atom or -COO- * (provided that the bonding hand (CH ₂ ) a is engaged with _2). in addition, a ₁ is an integer of 0, or 1, _2, a is an integer of 2 ~ 10, a ₃ represents an integer of 0 or 1.)

The bonding position of two amino groups (-NH ₂ ) in the formula (2) is not limited. Specifically, with respect to the coupler of the side chains, positions 2 and 3, positions 2 and 4, positions 2 and 5, positions 2 and 6, positions 3 and 4, positions 3 and 5 on the benzene ring . Among them, from the viewpoint of reactivity in the synthesis of polyamic acid, positions 2 and 4, positions 2 and 5, and positions 3 and 5 are preferable. When the ease of synthesis of the diamine is also considered, positions 2 and 4 or positions 3 and 5 are more preferable.

Specific examples of the formula (2) include, but are not limited to, diamines represented by the following formulas [A-1] to [A-24].

[Chemical formula 10]

(In the formulas [A-1] to [A-5], A ₁ is an alkyl group having 2 to 24 carbon atoms or a fluorine-

(11)

(In the formulas [A-6] and [A-7], A ₂ represents -O-, -OCH ₂ -, -CH ₂ O-, -COOCH ₂ - or -CH ₂ OCO- and A ₃ Is an alkyl group having 1 to 22 carbon atoms, an alkoxy group, a fluorine-containing alkyl group or a fluorine-containing alkoxy group.)

[Chemical Formula 12]

(In the formulas [A-8] to [A-10], A ₄ represents -COO-, -OCO-, -CONH-, -NHCO-, -COOCH ₂ -, -CH ₂ OCO-, -CH ₂ O -, -OCH ₂ -, or -CH ₂ -, and A ₅ is an alkyl group, an alkoxy group, a fluorine-containing alkyl group or a fluorine-containing alkoxy group having 1 to 22 carbon atoms.

[Chemical Formula 13]

(Wherein [A-11] and the equation [A-12] of, A ₆ is -COO-, -OCO-, -CONH-, -NHCO-, -COOCH 2 -, -CH 2 OCO-, -CH 2 O _{-, -OCH 2 -, -CH 2} -, -O-, or represents a -NH-, a ₇ is a fluorine group, a cyano group, a trifluoromethane group, a nitro group, an azo group, a formyl group, acetyl group, acetoxy Or a hydroxyl group.)

[Chemical Formula 14]

(In the formulas [A-13] and [A-14], A ₈ is an alkyl group having 3 to 12 carbon atoms and the cis-trans isomer of 1,4-cyclohexylene is a trans isomer.

[Chemical Formula 15]

(In the formulas [A-15] and [A-16], A ₉ is an alkyl group having 3 to 12 carbon atoms and the cis-trans isomer of 1,4-cyclohexylene is a trans isomer.

[Chemical Formula 16]

Specific examples of the diamine represented by the formula (3) include diamines represented by the following formulas [A-25] to [A-30], but are not limited thereto.

[Chemical Formula 17]

(Wherein [A-25] ~ formula [A-30] of, A ₁₂ is -COO-, -OCO-, -CONH-, -NHCO-, -CH 2 -, -O-, -CO-, or - NH-, and A ₁₃ represents an alkyl group having 1 to 22 carbon atoms or a fluorine-containing alkyl group.

Specific examples of the diamine represented by the formula (4) include diamines represented by the following formulas [A-31] to [A-32], but the present invention is not limited thereto.

[Chemical Formula 18]

Among these, [A-1], [A-2], [A-3], [A-4], [A- 5], and [A-2] are preferable from the viewpoints of the ability to vertically align liquid crystals, Diamines of [A-25], [A-26], [A-27], [A- 28], [A- 29] and [A-

The diamine may be used alone or in combination of two or more thereof depending on the properties of the liquid crystal alignment layer, such as liquid crystal alignability, pretilt angle, voltage holding characteristics, and accumulated charge.

Such a diamine having a side chain for orienting the liquid crystal vertically is used in an amount of 5 to 50 mol% of the total diamine component used for the synthesis of the polyimide precursor such as polyamic acid and the polyimide component (A) More preferably 10 to 40 mol% of the total diamine component is a diamine having a side chain that vertically aligns the liquid crystal, and particularly preferably 15 to 30 mol%. When the diamine having a side chain that vertically aligns the liquid crystal is used in an amount of 5 to 50 mol% of the total diamine component used for the synthesis of a polyimide precursor such as a polyamic acid or a polyimide, And is particularly excellent in terms of orientation fixation ability.

Examples of the diamine having a photoreactive side chain including at least one selected from methacryl group, acrylic group, vinyl group, allyl group, coumarin group, styryl group and cinnamoyl group include, for example, And diamines having a side chain represented by the following formula (1). More specifically, for example, the diamine represented by the following general formula (6) can be mentioned, but is not limited thereto.

[Chemical Formula 19]

(The definitions of R ⁸ , R ⁹ and R ^{10 in} the formula (6) are the same as those of the formula (b).)

The bonding position of two amino groups (-NH ₂ ) in the formula (6) is not limited. Specifically, with respect to the coupler of the side chains, positions 2 and 3, positions 2 and 4, positions 2 and 5, positions 2 and 6, positions 3 and 4, positions 3 and 5 on the benzene ring . Among them, from the viewpoint of reactivity in the synthesis of polyamic acid, positions 2 and 4, positions 2 and 5, and positions 3 and 5 are preferable. When the ease of synthesis of the diamine is also considered, positions 2 and 4, or positions 3 and 5 are more preferable.

Specific examples of the diamine having a photoreactive side chain containing at least one member selected from the group consisting of a methacryl group, an acryl group, a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group include the following compounds But is not limited to this.

[Chemical Formula 20]

(Wherein X is a single bond or a bonding group selected from -O-, -COO-, -NHCO-, -NH-, and Y is a single bond or a carbon-carbon double bond, An alkylene group having 1 to 20 carbon atoms.

The diamine having a photoreactive side chain containing at least one selected from the methacryl group, the acrylic group, the vinyl group, the allyl group, the coumarin group, the styryl group and the cinnamoyl group has a liquid crystal alignment property, One kind or two or more kinds may be mixed and used depending on characteristics such as pretilt angle, voltage holding characteristic, accumulated charge and the like, response speed of liquid crystal when the liquid crystal display element is used.

The diamine having a photoreactive side chain containing at least one selected from methacryl group, acrylic group, vinyl group, allyl group, coumarin group, styryl group and cinnamoyl group may be obtained by reacting the component (A) It is preferable to use an amount of 10 to 70 mol%, more preferably 20 to 60 mol%, and particularly preferably 30 to 50 mol% of the total diamine component used in the synthesis of the polyimide precursor and polyimide % to be.

The polyimide precursor or polyimide such as polyamic acid as the component (A) may contain a diamine having a side chain that vertically aligns the liquid crystal or a diamine having a photoreactive group Other diamine can be used in combination as the diamine component of the raw material. Specific examples include p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, m- , 4-dimethyl-m-phenylenediamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,5-diaminophenol, 2,4-diaminophenol, , 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, 4,4'-diaminobiphenyl, 3,3'-dimethyl- Diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl, 3,3'-dicarboxy 4,4'-diaminobiphenyl, 3,3'-difluoro-4,4'-biphenyl, 3,3'-trifluoromethyl-4,4'- Diaminobiphenyl, 3'-diaminobiphenyl, 2,2'-diaminobiphenyl, 2,3'-diaminobiphenyl, 4,4'-diaminodiphenylmethane, 3'- , 3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 2,2'-diaminodiphenylmethane, 2,3'-diamino Diaminodiphenyl ether, 2,2'-diaminodiphenyl ether, 2,2'-diaminodiphenyl ether, 2,2'-diaminodiphenyl ether, 2,3,4'-diaminodiphenyl ether, Bis (4-aminophenyl) silane, dimethyl-bis (4-aminophenyl) silane, -Aminophenyl) silane, dimethyl-bis (3-aminophenyl) silane, 4,4'-thiodianiline, 3,3'- thiodianiline, 4,4'- diaminodiphenylamine, - diaminodiphenylamine, 3,4'-diaminodiphenylamine, 2,2'-diaminodiphenylamine, 2,3'-diaminodiphenylamine, N-methyl (4,4'-dia (3,3'-diaminodiphenyl) amine, N-methyl (3,4'-diaminodiphenyl) amine, N-methyl (2,2'-diaminodiphenyl) Phenyl) amine, N-methyl (2,3'-diaminodiphenyl) amine, 4,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, 3,4'- 1,4-diaminonaphthalene, 2,2'-diaminobenzophene , 2,3'-diaminobenzophenone, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 1,8-diaminonaphthalene, Bis (4-aminophenyl) ethane, 1,2-bis (3-aminophenyl) ethane, 2,6-diaminonaphthalene, 2,6-diaminonaphthalene, Bis (4-aminophenyl) propane, 1,3-bis (3-aminophenyl) propane, ) Butane, bis (3,5-diethyl-4-aminophenyl) methane, 1,4-bis (4-aminophenoxy) benzene, (4-aminophenyl) benzene, 1,3-bis (4-aminophenoxy) benzene, 4,4 '- [1,4-phenylenebis (methylene)] dianiline, 4,4' - [ Phenylenebis (methylene)] dianiline, 3,3 '- [1,4-phenanthrene 1,4-phenylenebis [(4-aminophenyl) methanone], 1,4-phenylenebis (methylene)] dianiline, Phenylenebis [(3-aminophenyl) methanone], 1,3-phenylenebis [(4-aminophenyl) methanone] Phenylenebis (4-aminobenzoate), 1,4-phenylenebis (3-aminobenzoate), 1,3- (3-aminophenyl) isophthalate, bis (3-aminophenyl) isophthalate, bis (3-aminophenyl) isophthalate, bis , N, N '- (1,4-phenylene) bis (4-aminobenzamide) (4-aminobenzamide), N, N '- (1,3-phenylene) bis (3-aminobenzamide), N, N'- ) Terephthalamide, N, N'-bis (3-aminophenyl) terephthalate Bis (4-aminophenyl) isothiamides, N, N'-bis (3-aminophenyl) isophthalamide, 9,10- Bis [4- (4-aminophenoxy) phenyl] propane, 2,2'-bis [4- Bis (3-aminophenyl) hexafluoropropane, 2,2'-bis (3-aminophenyl) hexafluoropropane, 2,2'- Bis (3-aminophenyl) propane, 2,2'-bis (3-amino- Bis (4-aminophenoxy) propane, 1,3-bis (3-aminophenoxy) propane, Bis (4-aminophenoxy) butane, 1,5-bis (4-aminophenoxy) Bis (4-aminophenoxy) pentane, 1,6-bis (4-aminophenoxy) Heptane, 1,7-bis (4-aminophenoxy) heptane, 1,8-bis (4-aminophenoxy) , 1,9-bis (3-aminophenoxy) nonane, 1,10- (4-aminophenoxy) 1,10- (3-aminophenoxy) decane, 1,11- (3-aminophenoxy) undecane, 1,12- Aromatic diamines such as bis (4-aminophenoxy) dodecane and 1,12- (3-aminophenoxy) dodecane, bis (4-aminocyclohexyl) ) Methane, alicyclic diamines such as 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, Aliphatic diamines such as 8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, and 1,12-diaminododecane.

The other diamines may be used alone or in combination of two or more thereof depending on the properties such as liquid crystal alignability, pretilt angle, voltage holding characteristics, and accumulated charge when used as a liquid crystal alignment film.

The tetracarboxylic acid dianhydride component to be reacted with the diamine component in the synthesis of polyamic acid as the component (A) is not particularly limited. Specific examples include pyromellitic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 2,3,6,7-anthracene tetracarboxylic acid, 1,2,5,6-anthracene tetracarboxylic acid, 3,3 ', 4,4'-biphenyltetracarboxylic acid, 2,3,3 (3,4-dicarboxyphenyl) ether, 3,3 ', 4,4'-benzophenonetetracarboxylic acid, bis (3,4-dicarboxyphenyl) Sulfone, bis (3,4-dicarboxyphenyl) methane, 2,2-bis (3,4-dicarboxyphenyl) propane, 1,1,1,3,3,3-hexafluoro-2,2- (3,4-dicarboxyphenyl) propane, bis (3,4-dicarboxyphenyl) dimethylsilane, bis (3,4-dicarboxyphenyl) diphenylsilane, 2,3,4,5- (3,4-dicarboxyphenyl) pyridine, 3,3 ', 4,4'-diphenylsulfone tetracarboxylic acid, 3,4,9,10-perylenetetracarboxylic acid Acid, 1,3-diphenyl-1,2,3,4-cyclobutanetetracar Oxydipetetracarboxylic acid, 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, 1,2,4,5-cyclohexane Tetracarboxylic acid, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutane tetracarboxylic acid, 1,2-dimethyl-1,2,3,4-cyclobutane tetracarboxyl Acid, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic acid, 1,2,3,4-cycloheptane tetracarboxylic acid, 2,3,4,5-tetrahydrofuran tetra Carboxylic acid, 3,4-dicarboxy-1-cyclohexylsuccinic acid, 2,3,5-tricarboxycyclopentylacetic acid, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene Succinic acid, bicyclo [3,3,0] octane-2,4,6,8-tetracarboxylic acid, bicyclo [4,3,0] nonane-2,4,7,9-tetracarboxylic acid, Bicyclo [4,4,0] decane-2,4,7,9-tetracarboxylic acid, bicyclo [4,4,0] decane-2,4,8,10-tetracarboxylic acid, tricyclo [6.3.0.0 &lt; 2,6 &gt;] undecane-3,5,9,11-tetracarboxylic acid, 1,2,3,4-butanetetracarboxylic acid, 4- (2,5-dioxotetrahydrofuran-3-yl) -1,2,3,4-tetrahydronaphthalene- 2,2,2] octo-7-ene-2,3,5,6-tetracarboxylic acid, 5- (2,5-dioxotetrahydrofuryl) -3-methyl- - cyclohexane-1,2-dicarboxylic acid, tetracyclo [6,2,1,1,0,2,7] dodeca-4,5,9,10-tetracarboxylic acid, 3,5, 6-tricarboxy norbornane-2: 3,5: 6 dicarboxylic acid, and 1,2,4,5-cyclohexanetetracarboxylic acid. Of course, the tetracarboxylic acid dianhydride may be used alone or in combination of two or more, depending on the properties such as liquid crystal aligning property, voltage holding property, and accumulated charge when the liquid crystal alignment film is used.

In the production of the polyamic acid by the reaction of the raw diamine (also referred to as "diamine component") and the raw tetracarboxylic acid dianhydride (also referred to as "tetracarboxylic acid dianhydride component"), Techniques can be used. Generally, it is a method of reacting a diamine component and a tetracarboxylic acid dianhydride component in an organic solvent. The reaction between the diamine component and the tetracarboxylic acid dianhydride component is advantageous in that it proceeds relatively easily in an organic solvent and does not generate any by-products.

The organic solvent used in the above reaction is not particularly limited as long as it dissolves the produced polyamic acid and the like. Even if the organic solvent does not dissolve the polyamic acid or the like, it may be mixed with the solvent in the range where the produced polyamic acid and the like are not precipitated. In addition, water in the organic solvent inhibits the polymerization reaction, and further causes hydrolysis of the produced polyamic acid and the like, and therefore, the organic solvent is preferably dehydrated and dried. Examples of the organic solvent used in the reaction include N, N-dimethylformamide, N, N-dimethylacetamide, N, N-diethylformamide, N-methylformamide, Pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, 3-methoxy-N, N-dimethylpropanamide, N- But are not limited to, lactam, dimethylsulfoxide, tetramethylurea, pyridine, dimethylsulfone, hexamethylsulfoxide,? -Butyrolactone, isopropyl alcohol, methoxymethyl pentanol, dipentene, ethyl amyl ketone, , Methyl isoamyl ketone, methyl isopropyl ketone, methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, butyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol, ethylene glycol , Ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol Propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol, diethylene glycol monoacetate , Diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol mono Propyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, di Isobutylene, amyl acetate Butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, dioxane, n-hexane, n-pentane, n-octane, diethyl ether, cyclohexanone, ethylene carbonate Propylene carbonate, methyl lactate, methyl lactate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether acetate, methyl pyruvate, methyl pyruvate, methyl 3- Methoxypropionate, butyl 3-methoxypropionate, diglyme, 4-hydroxy-4-methyl-2-pentanone, 2-methoxypropionate, 3-methoxypropionic acid, -Ethyl-1-hexanol, and the like. These organic solvents may be used alone or in combination.

When the diamine component and the tetracarboxylic acid dianhydride component are reacted in an organic solvent, the solution in which the diamine component is dispersed or dissolved in an organic solvent is stirred and the tetracarboxylic acid dianhydride component is dispersed or dissolved in the organic solvent as it is A method of adding a diamine component to a solution in which a tetracarboxylic acid dianhydride component is dispersed or dissolved in an organic solvent, a method of alternately adding a tetracarboxylic acid dianhydride component and a diamine component, and the like , Or any of these methods may be used. When the diamine component or the tetracarboxylic acid dianhydride component is composed of a plurality of compounds, they may be reacted in advance in a mixed state, or they may be sequentially reacted individually, and the low molecular weight compounds reacted individually may be mixed and reacted, May be used.

The temperature at which the diamine component is reacted with the tetracarboxylic acid dianhydride component can be selected from any temperature, for example, from -20 ° C to 150 ° C, preferably from -5 ° C to 100 ° C. The reaction can be carried out at any concentration. For example, the total amount of the diamine component and the tetracarboxylic acid dianhydride component relative to the reaction solution is 1 to 50 mass%, preferably 5 to 30 mass%.

The ratio of the total molar amount of the tetracarboxylic acid dianhydride component to the total molar amount of the diamine component in the above polymerization reaction can be selected according to the molecular weight of the polyamic acid to be obtained. As in the case of the usual polycondensation reaction, the closer the molar ratio is to 1.0, the larger the molecular weight of the produced polyamic acid or the like. It is 0.8 to 1.2 if it shows a preferable range.

 The method of synthesizing the polyamic acid to be used in the present invention is not limited to the above method. Instead of the above tetracarboxylic acid dianhydride, a tetracarboxylic acid or tetracarboxylic acid The corresponding polyamic acid can also be obtained by using a tetracarboxylic acid derivative such as an acid halide or the like and reacting it by a known method.

Examples of the method of imidizing a polyimide precursor such as the polyamic acid described above into a polyimide include a method in which a solution of a polyimide precursor such as a polyamic acid or the like is directly heated to a solution of a polyimide precursor such as a polyimide precursor And a catalyst imidization to which the catalyst is added. In addition, the imidation rate from polyimide precursor such as polyamic acid to polyimide does not necessarily have to be 100%.

The temperature at which the polyamic acid is thermally imidized in the solution is 100 ° C to 400 ° C, preferably 120 ° C to 250 ° C, and it is preferable to carry out the removal while removing the water generated by the imidization reaction out of the system.

The catalyst imidation of polyamic acid can be carried out by adding a basic catalyst and acid anhydride to a solution of polyamic acid and stirring at -20 to 250 캜, preferably 0 to 180 캜. The amount of the basic catalyst is 0.5 to 30 moles, preferably 2 to 20 moles, of the amide group, and the amount of the acid anhydride is 1 to 50 moles, preferably 3 to 30 moles, of the amide group. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, trioctylamine and the like. Of these, pyridine is preferable because it has a basicity suitable for proceeding the reaction. As the acid anhydride, acetic anhydride, trimellitic anhydride, pyromellitic anhydride and the like can be given. Among them, acetic anhydride is preferable because the purification after completion of the reaction becomes easy. The imidization rate by the catalyst imidization can be controlled by adjusting the catalyst amount, the reaction temperature, and the reaction time.

When a polyimide precursor such as polyamic acid or polyimide is recovered from a polyimide precursor such as polyamic acid or a reaction solution of polyimide, the reaction solution may be introduced into a poor solvent and precipitated. Examples of the poor solvent used in the precipitation include methanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene and water. The polymer precipitated by charging into a poor solvent can be recovered by filtration and then dried at normal temperature or under reduced pressure or by heating. In addition, when the polymer precipitated and recovered is redissolved in an organic solvent, and the operation of re-precipitation and recovery is repeated 2 to 10 times, impurities in the polymer can be reduced. As the poor solvent in this case, for example, alcohols, ketones, hydrocarbons and the like can be mentioned, and when three or more poor solvents selected from these are used, the purification efficiency is further improved, which is preferable.

[Component (B)] [

The liquid crystal aligning agent of the present invention contains, as a component (B), a polymerizable compound having a group capable of photo-polymerization or photo-crosslinking at one or more terminals. That is, the component (B) which is the polymerizable compound contained in the liquid crystal aligning agent of the present invention is a compound having at least one terminal having a group capable of photopolymerization or photo-crosslinking. Here, the polymerizable compound having a photopolymerizable group is a compound having a functional group that generates polymerization upon irradiation of light. The polymerizable compound having a group capable of photo-crosslinking is a compound having a functional group capable of reacting with a polymer of a polymerizable compound or a polymer as the component (A) or the component (C) by irradiation with light. The polymerizable compound having a photo-crosslinkable group also reacts with the polymerizable compound having a photo-crosslinkable group.

Such a polymerizable compound is preferably used in combination with a side chain for vertically orienting a liquid crystal and a photoreactive compound containing at least one member selected from methacrylic group, acrylic group, vinyl group, allyl group, coumarin group, styryl group, (A), which is at least one kind of polymer selected from a polyimide precursor obtained by imidizing a polyimide precursor and a polyimide precursor having a side chain, is contained in the liquid crystal aligning agent, , It is possible to improve the response speed dramatically even when a polymer having a side chain and a photoreactive side chain that vertically aligns the liquid crystal or a polymerizable compound is used alone , And the response speed can be sufficiently improved even with a small addition amount of the polymerizable compound.

The photopolymerization or photocrosslinking group includes a monovalent group represented by the above formula (II).

Specific examples of the component (B) that is a polymerizable compound include a polymerizable compound having a group capable of photo-polymerizing at each of two terminals as shown by the following formula (III), a group capable of photo-polymerization as shown by the following formula (IV) , And a polymerizable compound having a group capable of photo-crosslinking at two terminals as shown by the following formula (V). Further, according to the following formula (III) ~ (V), R 12, Z 1 and Z ² is R ^12, Z ¹ and Z ^2, identical, Q ¹ in the formula (II) is a divalent an organic . Q ¹ has a cyclic structure such as a phenylene group (-C ₆ H ₄ -), a biphenylene group (-C ₆ H ₄ -C ₆ H ₄ -) or a cyclohexylene group (-C ₆ H ₁₀ -) . This is because the interaction with the liquid crystal tends to become large.

[Chemical Formula 21]

[Chemical Formula 22]

(23)

Specific examples of the polymerizable compound represented by the formula (III) include the following polymerizable compounds. In the formulas, V is a single bond or -R ¹ O- and R ¹ is an alkylene group having 1 to 10 carbon atoms in a linear or branched chain, preferably represented by -R ¹ O- and R ¹ is a linear chain Or branched alkylene group having 2 to 6 carbon atoms. W is a single bond or -OR ² - and R ² is an alkylene group having 1 to 10 carbon atoms in a linear or branched chain, preferably -OR ² - and R ² is a linear or branched An alkylene group having 2 to 6 carbon atoms. V and W may have the same structure or different from each other, but if they are the same, synthesis is easy.

&Lt; EMI ID =

Since the polymerizable compound represented by the above formula is a compound having a specific structure having an? -Methylene-? -Butyrolactone group as a polymerizable group at both ends, the polymer may have a rigid structure, An SC-PVA type liquid crystal display in which at least one kind of polymer selected from a polyimide precursor and a polyimide obtained by imidizing the polyimide precursor is used as a material for a liquid crystal alignment film, as shown in the following embodiments By using the liquid crystal display element of the vertical alignment type for manufacturing liquid crystal display elements, the response speed can be remarkably improved. In general, the process of forming a liquid crystal alignment film includes a step of baking at a high temperature in order to completely remove the solvent. In the case of a compound having a polymerizable group such as an acrylate group, a methacrylate group, a vinyl group, a vinyloxy group and an epoxy group It is difficult to withstand firing at high temperature due to lack of thermal stability. On the other hand, since the polymerizable compound having an? -Methylene-? -Butyrolactone group at both ends has a structure lacking thermal polymerization property, it is difficult to sufficiently heat the polymerizable compound at a high temperature, for example, You can.

Further, even when a polymerizable compound having an acrylate group or a methacrylate group is used instead of an? -Methylene-? -Butyrolactone group as a photopolymerization or photocrosslinking group, the acrylate group or the methacrylate group may be replaced with a spacer such as an oxyalkylene group , It is possible to remarkably improve the response speed particularly in the same manner as the polymerizable compound having the? -Methylene-? -Butyrolactone group at both ends of the polymerizable compound. A polymerizable compound having a structure in which an acrylate group or a methacrylate group is bonded to a phenylene group via a spacer such as an oxyalkylene group may be used for the purpose of improving the stability against heat, It can withstand temperatures well.

As another specific example of the polymerizable compound represented by the formula (III), a polymerizable compound represented by the following formula can be given.

(25)

(In the formula, V is a bond or is represented by -R ¹ O- R ¹ is a straight-chain or branched having 1 to 10 carbon atoms in the alkylene group and preferably is represented by -R ¹ O- R ¹ is straight- an alkylene group of chain or branched having 2 to 6 carbon atoms in addition, W is a single bond or -OR ² -. and is represented by R ² are straight-chain or a carbon number of 1-10 alkylene group of branches, preferably -OR ² - is represented by R ² is a straight-chain or alkylene group of a carbon number of 2-6 of the branch V and W may be even the same structures differ, but the synthesis is easy when the same addition, R ¹² is H or C 1 Lt; 4 &gt;).

&Lt; Production method of component (B)

The method for producing the component (B), which is the polymerizable compound, is not particularly limited, and can be produced, for example, according to a synthesis example described later. For example, the polymerizable compound represented by the following formula (1) can be synthesized by combining the techniques in organic synthesis chemistry. For example, to include a Tallahassee shown in Scheme P. Talaga, M. Schaeffer, C. Benezra and JL Stampf, Synthesis, 530 (1990) by the method proposed in, using SnCl ₂ 2- (Bromo Methyl) acrylic acid (2- (bromomethyl) propenoic acid) with an aldehyde or a ketone. Amberlyst 15 is a strongly acidic ion exchange resin manufactured by Rohm and Haas.

(26)

(27)

(Wherein R 'represents a monovalent organic group).

In addition, 2- (bromomethyl) acrylic acid can be obtained by reacting a 2- (bromomethyl) acrylic acid represented by the following reaction formula with K. Ramarajan, K. Kamalingam, D. J. O'Donnell and K. D. Berlin, Organic Synthesis, vol. 61, 56-59 (1983).

(28)

As a specific synthesis example, when a polymerizable compound represented by the above formula (1) is synthesized in which V is -R ¹ O-, W is -OR ² - and R ¹ and R ² are the same, two Method.

[Chemical Formula 29]

(30)

When a polymerizable compound represented by the above formula (1) in which R ¹ and R ² are different from each other is synthesized, a method represented by the following reaction formula can be given.

(31)

In the case of synthesizing a polymerizable compound represented by the above formula (1) in which V and W are single bonds, the following reaction scheme can be mentioned.

(32)

[Component (C)] [

The liquid crystal aligning agent of the present invention is a liquid crystal aligning agent which comprises, as the component (C), a photoreactive side chain comprising at least one member selected from a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group (C-1) to (C-5), and a tetracarboxylic acid dianhydride, and a polyimide precursor obtained by reacting the polyimide precursor with at least one diamine selected from the above formulas And a polymer selected from a polyimide obtained by subjecting a polyimide to a polymerization reaction.

The definition and specific examples of the "photoreactive side chain including at least one selected from a methacryl group, an acryl group, a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group" Component]. Specific examples of the diamine having a photoreactive side chain including at least one selected from a methacryl group, an acryl group, a vinyl group, an allyl group, a coumarin group, a styryl group, and a cinnamoyl group, Component].

The diamine having a photoreactive side chain including at least one selected from methacryl group, acrylic group, vinyl group, allyl group, coumarin group, styryl group and cinnamoyl group is preferably a poly It is preferable to use an amount of 10 mol% to 60 mol%, more preferably 10 mol% to 40 mol%, and particularly preferably 10 mol% to 40 mol% of the total diamine component used in the synthesis of the polyimide precursor and polyimide 20 mol% to 30 mol%.

The polymer as the component (C) also contains at least one diamine selected from the above-mentioned formulas (C-1) to (C-5) as raw materials. When at least one kind of diamine selected from the above-mentioned formulas (C-1) to (C-5) is also used as a raw material, they can improve the accumulation charge characteristics because they are diamines having a specific polar structure. Examples of the at least one diamine selected from the above-mentioned formulas (C-1) to (C-5) include the following diamines, but are not limited thereto.

(33)

At least one kind of diamine selected from the above-mentioned formulas (C-1) to (C-5) is preferably 10 mol of the total diamine component used for the synthesis of the polyimide precursor and polyimide such as the polyamic acid as the component (C) % To 80 mol% based on the total amount of the composition.

In addition, as long as the effect of the present invention is not impaired, even if a diamine or other diamine having a side chain that vertically aligns the liquid crystal described in the [component (A)] is used as a raw material for the component (C) do. For example, when a diamine having a side chain for vertically orienting a liquid crystal is also used as a raw material, a diamine having a side chain for vertically orienting the liquid crystal may be used as a polyimide precursor such as a polyamic acid as the component (C) It is preferable to use an amount of 10 to 30 mol% of the total diamine component used in the synthesis of the diamine component.

The tetracarboxylic acid dianhydride component to be reacted with the diamine component is the same as the tetracarboxylic acid dianhydride component described in the above [component (A)].

The method for producing the component (C) includes a step of reacting a diamine having a photoreactive side chain containing at least one member selected from the group consisting of a methacryl group, an acryl group, a vinyl group, an allyl group, a coumarin group, a styryl group, A diamine having at least one kind of diamine selected from the above-mentioned formulas (C-1) to (C-5), a tetracarboxylic acid dianhydride and further, side chains for vertically orienting the liquid crystal, Other diamine or the like may be reacted to obtain a polyimide precursor or polyimide. (A), except that at least one kind of diamine selected from the above-mentioned formulas (C-1) to (C-5) is also used as a raw material .

As described above, the liquid crystal aligning agent of the present invention is a liquid crystal aligning agent which has a side chain for vertically orienting a liquid crystal and at least one selected from a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group (A) which is at least one kind of polymer selected from a polyimide precursor having a photoreactive side chain including one kind of polyimide precursor and a polyimide obtained by imidizing the polyimide precursor, (B) which is a polymerizable compound having a photo-crosslinking group or a photo-crosslinking group and a photoreactive side comprising at least one member selected from a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group A polyimide precursor obtained by reacting a diamine having a chain with a diamine of a predetermined structure selected from the above formulas (C-1) to (C-5) and a tetracarboxylic acid dianhydride, (B) component is contained in 100 parts by mass of the component (A). The amount of the component (B) is not particularly limited as long as it has a solvent and a component selected from polyimides obtained by imidizing a polyimide Is preferably 1 to 50 parts by mass, more preferably 5 to 30 parts by mass. The content of the component (A) of the liquid crystal aligning agent of the present invention is preferably from 1% by mass to 20% by mass, more preferably from 3% by mass to 15% by mass, and particularly preferably from 3% by mass to 10% to be.

The content ratio of the component (A) to the component (C) is not particularly limited. For example, the ratio of the component (A): component (C) is 1: 9 to 5: 5.

The liquid crystal aligning agent of the present invention may contain a polymer other than the component (A) and the component (C). At this time, the content of such another polymer in the entire polymer component is preferably 0.5% by mass to 15% by mass, and more preferably 1% by mass to 10% by mass.

The molecular weight of the polymer having the liquid crystal aligning agent is preferably in the range of from 0.1 to 10 parts by weight based on the weight average molecular weight measured by GPC (Gel Permeation Chromatography), considering the strength of the liquid crystal alignment film obtained by applying the liquid crystal aligning agent, The molecular weight is preferably 5,000 to 1,000,000, more preferably 10,000 to 150,000.

The solvent contained in the liquid crystal aligning agent is not particularly limited and may be any solvent capable of dissolving or dispersing the components (A), (B), and (C). For example, organic solvents as exemplified in the synthesis of the polyamic acid and the like can be mentioned. Among them, N-methyl-2-pyrrolidone,? -Butyrolactone, N-ethyl-2-pyrrolidone, Dimethyl propanamide is preferable from the viewpoint of solubility. Of course, two or more types of mixed solvents may be used.

In addition, it is preferable to use a solvent which improves the uniformity and smoothness of the coating film in a solvent having high solubility of the component containing the liquid crystal aligning agent. Examples of the solvent that improves the uniformity and smoothness of the coating film include isopropyl alcohol, methoxymethyl pentanol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl cellosolve acetate, butyl cell But are not limited to, sucrose acetate, ethylcellosolve acetate, butylcarbitol, ethylcarbitol, ethylcarbitol acetate, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol mono Propylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl Ether, dipropylene glycol monoacetate monomethyl ether, dipropylene Glycol monomethyl ether, propylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3- Propyl ether, isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methyl ethyl ketone, Propyl ether, n-pentane, n-octane, diethyl ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl acetate Ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methylethyl 3-ethoxypropionate, 3-methoxy Methoxypropionate, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-methoxypropionate, 1-methoxypropionate, 2-propanol, propylene glycol monoacetate, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2 Ethyl acetate, lactic acid ethyl ester, n-propyl lactate, n-butyl lactate, isoamyl lactate, 2-ethyl-1-pentyl lactate, - hexanol and the like. These solvents may be mixed with a plurality of kinds. When these solvents are used, it is preferably 5 to 80 mass%, more preferably 20 to 60 mass%, of the total solvent contained in the liquid crystal aligning agent.

The liquid crystal aligning agent may contain components other than those described above. Examples thereof include a compound which improves film thickness uniformity and surface smoothness when a liquid crystal aligning agent is applied, a compound which improves the adhesion between the liquid crystal alignment film and the substrate, and the like.

Examples of the compound that improves film thickness uniformity and surface smoothness include a fluorine-based surfactant, a silicon-based surfactant, and a nonionic surface-active agent. More specifically, for example, EF301, EF303, EF352 (manufactured by TOKEM PRODUCTS CO., LTD.), Megapuck F171, F173, R-30 (manufactured by Dainippon Ink and Chemicals Inc.), Fluorad FC430 and FC431 manufactured by Sumitomo 3M ), Asahi Guard AG710, Surfron S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by Asahi Kagaku Co., Ltd.). When these surfactants are used, the proportion thereof is preferably 0.01 to 2 parts by mass, more preferably 0.01 to 1 part by mass, based on 100 parts by mass of the total amount of the polymer contained in the liquid crystal aligning agent.

Specific examples of the compound that improves the adhesion between the liquid crystal alignment layer and the substrate include a functional silane-containing compound and an epoxy group-containing compound. For example, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl) -3 3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxy (3-aminopropyl) Aminopropyltriethoxysilane, N-trimethoxysilylpropyltriethoxysilane, N-trimethoxysilylpropyltriethoxysilane, N-trimethoxysilylpropyltriethoxysilane, N-trimethoxysilylpropyltriethoxysilane, Amine, 10-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-benzyl-3-aminopropyltriethoxysilane, N- Bis (oxyethylene) -3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N- Aminopropyltriethoxysilane, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neo Pentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3,5,6 -Tetraglycidyl-2,4-hexanediol, N, N, N ', N'-tetraglycidyl-m-xylylenediamine, 1,3-bis (N, N-diglycidylaminomethyl ) N, N ', N'-tetraglycidyl-4,4'-diaminodiphenylmethane, 3- (N-allyl-N-glycidyl) aminopropyltrimethoxysilane, 3- (N, N-diglycidyl) And the like can be given no trimethoxysilane. In order to further increase the film strength of the liquid crystal alignment film, a phenol compound such as 2,2'-bis (4-hydroxy-3,5-dihydroxymethylphenyl) propane or tetra (methoxymethyl) bisphenol may be added. When these compounds are used, it is preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, based on 100 parts by mass of the total amount of the polymer contained in the liquid crystal aligning agent.

The liquid crystal aligning agent may be added with a dielectric material or a conductive material for the purpose of changing electric characteristics such as the dielectric constant and conductivity of the liquid crystal alignment film as long as the effect of the present invention is not impaired.

This liquid crystal aligning agent is coated on the substrate and baked to form a liquid crystal alignment film for vertically aligning the liquid crystal. The liquid crystal aligning agent of the present invention is a liquid crystal aligning agent comprising a side chain for vertically orienting a liquid crystal and a light containing at least one kind selected from methacrylic group, acrylic group, vinyl group, allyl group, coumarin group, styryl group and cinnamoyl group (A) which is at least one kind of polymer selected from a polyimide precursor having reactive side chains and a polyimide obtained by imidizing the polyimide precursor, together with a group capable of photo-polymerization or photo-crosslinking at one or more terminals (B), which is a polymerizable compound having a polymerizable functional group, in the liquid crystal display device using the obtained liquid crystal alignment film. As the polymer, not only the component (A) but also a diamine having a photoreactive side chain containing at least one member selected from a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group, , A polyimide precursor obtained by reaction of at least one diamine selected from the above-mentioned formulas (C-1) to (C-5) with a tetracarboxylic acid dianhydride, and a polyimide precursor obtained by imidizing the polyimide precursor (C) which is at least one kind of polymer selected from polyimide, it is possible to improve the accumulated charge characteristics.

At this time, the substrate to be used is not particularly limited as long as it is a substrate having high transparency, and a glass substrate, a plastic substrate such as an acrylic substrate or a polycarbonate substrate, or the like can be used. It is preferable to use a substrate on which an ITO electrode or the like for liquid crystal driving is formed from the viewpoint of simplifying the process. In the reflection type liquid crystal display device, an opaque material such as a silicon wafer can be used only for a substrate on one side. In this case, a material for reflecting light such as aluminum can also be used as the electrode in this case.

The method of applying the liquid crystal aligning agent is not particularly limited, and examples thereof include screen printing, offset printing, flexographic printing, inkjet, dip, roll coater, slit coater and spinner.

The baking temperature of the coating film formed by applying the liquid crystal aligning agent is not particularly limited and may be, for example, at any temperature of 100 to 350 ° C, preferably 120 to 300 ° C, 250 ° C. The firing can be performed by a hot plate, a hot air circulation path, an infrared ray lamp, or the like.

The thickness of the liquid crystal alignment film obtained by baking is not particularly limited, but is preferably 5 to 300 nm, and more preferably 10 to 100 nm.

The liquid crystal display element of the present invention comprises two substrates arranged so as to face each other, a liquid crystal layer formed between the substrates, and a liquid crystal alignment layer formed between the substrate and the liquid crystal layer and formed by the liquid crystal aligning agent of the present invention And is a vertical alignment type liquid crystal display device having a liquid crystal cell. More specifically, a liquid crystal alignment film is formed by applying the liquid crystal aligning agent of the present invention on two substrates and firing, and two substrates are arranged so that the liquid crystal alignment films face each other. And a liquid crystal cell produced by sandwiching the constituent liquid crystal layer and irradiating ultraviolet rays while applying a voltage to the liquid crystal alignment film and the liquid crystal layer. As described above, by using the liquid crystal alignment film formed by the liquid crystal aligning agent of the present invention, ultraviolet rays are irradiated while applying a voltage to the liquid crystal alignment film and the liquid crystal layer to polymerize the polymerizable compound, , By reacting the polymerizable compound with the photoreactive side chain possessed by the polymer, the alignment of the liquid crystal is more efficiently fixed, and a liquid crystal display element having a remarkably superior response speed is obtained. In addition, a liquid crystal display element having a small accumulated charge is obtained.

The substrate used in the liquid crystal display of the present invention is not specifically limited as long as it is a substrate having high transparency, but is usually a substrate on which a transparent electrode for driving liquid crystal is formed. Specific examples include the same substrates as those described in the liquid crystal alignment film. A substrate on which a conventional electrode pattern or a projection pattern is formed may be used. In the liquid crystal display element of the present invention, since the liquid crystal aligning agent of the present invention is used as a liquid crystal aligning agent for forming a liquid crystal alignment film, It is possible to operate in a structure in which a line / slit electrode pattern of 10 mu m is formed and a slit pattern or a projection pattern is not formed in the counter substrate. With the liquid crystal display element of this structure, the manufacturing process can be simplified And a high transmittance can be obtained.

In a high-performance device such as a TFT-type device, a device such as a transistor is formed between an electrode for liquid crystal driving and a substrate.

In the case of a transmissive liquid crystal display device, it is common to use such a substrate, but in a reflective liquid crystal display device, it is possible to use an opaque substrate such as a silicon wafer if it is only on one substrate. At this time, a material such as aluminum that reflects light may be used for the electrode formed on the substrate.

The liquid crystal alignment film is formed by applying the liquid crystal aligning agent of the present invention on this substrate and then firing it, and the details are as described above.

The liquid crystal material constituting the liquid crystal layer of the liquid crystal display element of the present invention is not particularly limited and liquid crystal materials used in conventional vertical alignment methods such as MLC-6608 and MLC-6609 manufactured by Merck & Can be used.

As a method of sandwiching the liquid crystal layer between two substrates, known methods can be mentioned. For example, a pair of substrates on which a liquid crystal alignment film is formed is prepared, spacers such as beads are scattered on the liquid crystal alignment film of one substrate, and the other side of the substrate is bonded (Bonded), and the liquid crystal is injected under reduced pressure and sealed. A pair of substrates on which a liquid crystal alignment film is formed is prepared, a spacer such as beads is dispersed on a liquid crystal alignment film of one of the substrates, and liquid crystal is dropped thereon. Thereafter, A liquid crystal cell can also be manufactured by a method in which one substrate is bonded and sealed. The thickness of the spacer at this time is preferably 1 to 30 占 퐉, more preferably 2 to 10 占 퐉.

The step of producing a liquid crystal cell by irradiating ultraviolet rays while applying a voltage to a liquid crystal alignment film and a liquid crystal layer is performed by applying an electric field to a liquid crystal alignment film and a liquid crystal layer by applying a voltage between electrodes provided on the substrate, And a method of irradiating ultraviolet rays while maintaining the electric field. Here, the voltage applied between the electrodes is, for example, 5 to 30 Vp-p, preferably 5 to 20 Vp-p. The irradiation amount of ultraviolet rays is, for example, 1 to 60 J or less, preferably 40 J or less. When the amount of ultraviolet irradiation is small, reliability deterioration caused by destruction of members constituting the liquid crystal display element can be suppressed Since the ultraviolet ray irradiation time can be reduced, the manufacturing efficiency is increased, which is suitable.

Thus, when ultraviolet rays are irradiated while applying a voltage to the liquid crystal alignment film and the liquid crystal layer, the polymerizable compound reacts to form a polymer, and the direction in which the liquid crystal molecules incline is memorized by the polymer, . When the ultraviolet rays are irradiated while a voltage is applied to the liquid crystal alignment film and the liquid crystal layer, the photoreactive side chains of the component (A) or the component (C) Since the side chain is reacted with the component (B) as the polymerizable compound, the response speed of the obtained liquid crystal display element can be increased, and the accumulated charge characteristics are also improved.

The liquid crystal aligning agent is not only useful as a liquid crystal aligning agent for producing a liquid crystal display element of a vertical alignment type such as a PSA type liquid crystal display or an SC-PVA type liquid crystal display, but also a liquid crystal aligning agent produced by rubbing treatment or photo- And can be suitably used for a liquid crystal alignment film.

Example

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

[Example]

&Lt; Preparation of liquid crystal aligning agent &

The abbreviations used in the preparation of the following liquid crystal aligning agent are as follows.

· Acid 2 anhydride

BODA: bicyclo [3,3,0] octane-2,4,6,8-tetracarboxylic acid dianhydride

CBDA: 1,2,3,4-Cyclobutane tetracarboxylic acid dianhydride

TCA: 2,3,5-tricarboxycyclopentylacetic acid dianhydride

· Diamine

p-PDA: p-phenylenediamine

m-PDA: m-Phenylenediamine

PCH: 1,3-diamino-4- [4- (4-heptylcyclohexyl) phenoxy] benzene

DBA: 3,5-diaminobenzoic acid

BEM-S: 2- (methacryloyloxy) ethyl 3,5-diaminobenzoate represented by the following formula

(34)

3AMPDA: 3,5-diamino-N- (pyridin-3-ylmethyl) benzamide represented by the following formula

(35)

DADPA: N ¹ - (4-aminophenyl) benzene-1,4-diamine represented by the following formula

(36)

DA-Col: 3,5-diaminobenzoic acid cholestanyl

·menstruum

NMP: N-methyl-2-pyrrolidone

BCS: butyl cellosolve

· Polymerizable compound

RM1: Polymerizable compound represented by the following formula 5,5 '- (4,4' - (biphenyl-4,4'-diyl bis (oxy)) bis (butane-4,1-diyl) bis Dihydrofuran-2 (3H) -one)

(37)

(Synthesis of polymerizable compound (RM1)

(35.7 mmol) of 4,4'-biphenol and 15.0 g (71.7 mmol) of 2- (4-bromobutyl) -1,3-dioxolane were placed in a 300 ml eggplant- , Potassium carbonate (19.8 g, 143 mmol) and acetone (150 ml) were added to the mixture, and the mixture was reacted at 60 占 폚 with stirring for 48 hours. After completion of the reaction, the solvent was distilled off under reduced pressure to obtain a yellow wet solid. Thereafter, this solid and 200 ml of water were mixed, and 80 ml of chloroform was added to extract. Extraction was carried out three times.

Anhydrous magnesium sulfate was added to the separated organic layer, followed by drying. After filtration, the solvent was distilled off under reduced pressure to obtain a yellow solid. This solid was recrystallized (hexane / chloroform = 4/1 (volume ratio)) to obtain 14.6 g of a white solid. The result of measurement of the obtained white solid by NMR is shown below. The obtained solid was dissolved in deuterated chloroform (CDCl ₃ ) and measured at 300 MHz using a nuclear magnetic resonance apparatus (manufactured by Diol). From this result, it was confirmed that the white solid was the intermediate compound (RM1-A) shown in the following reaction formula. The yield was 92%.

(38)

Next, 13.3 g (30 mmol) of the intermediate compound (RM1-A) obtained above, 11.6 g (70 mmol) of 2- (bromomethyl) acrylic acid, 10% 50 ml of hydrochloric acid (aq), 160 ml of tetrahydrofuran (THF) and 13.2 g (70 mmol) of tin (II) chloride were added to the mixture and the mixture was reacted at 70 DEG C for 20 hours with stirring. After completion of the reaction, the reaction solution was filtered under reduced pressure, mixed with 200 ml of pure water, and 100 ml of dichloroform was added thereto to extract. Extraction was carried out three times.

Anhydrous magnesium sulfate was added to the separated organic layer, followed by drying. The solvent was distilled off from the solution after filtration under reduced pressure to obtain a white solid. This solid was recrystallized (hexane / chloroform = 2/1) to obtain 9.4 g of a white solid. The obtained white solid was measured by NMR in the same manner as described above. As a result, it was confirmed that the white solid was the polymerizable compound (RM1) represented by the objective formula shown below. The yield was 64%.

[Chemical Formula 39]

RM2: Polymerizable compound represented by the following formula 5,5 '- (4,4' - (propane-2,2-diyl) bis (4,1- phenylene)) bis (oxy) bis -Diyl) bis (2-methacrylate)

(40)

RM2 was obtained in accordance with the method described in JP-A-63-79853.

RM3: Polymerizable compound represented by the following formula: 5,5 '- (4,4'-carbonylbis (4,1-phenylene) bis (oxy) Methacrylate)

(41)

(4,4'- (4,4'-carbonylbis (4,1-phenylene) bis (oxy)) bis (vinylidene fluoride) of BP1 (Japanese Patent Application No. 2011-252101) (Butane-4,1-diyl) bis (2-methacrylate)), RM3 was obtained by the following reaction.

(42)

The conditions for measuring the molecular weight of the polymer (polyimide or polyamic acid) are as follows.

Apparatus: Room temperature gel permeation chromatography (GPC) apparatus (SSC-7200) manufactured by Senshu Scientific Corporation,

Column: Column (KD-803, KD-805) manufactured by Shodex Co.,

Column temperature: 50 ° C

Eluent: 30 mmol / l of lithium bromide · hydrate (LiBr · H ₂ O), 30 mmol / l of phosphoric anhydride crystal (o-phosphoric acid) as an additive, N, N'-dimethylformamide Furan (THF) of 10 ml / l)

Flow rate: 1.0 ml / min

Standard sample for preparing calibration curve: TSK standard polyethylene oxide (molecular weight: about 900,000, 150,000, 100,000, 30,000) manufactured by Toso Corporation and polyethylene glycol (molecular weight about 12,000, 4,000, 1,000) manufactured by Polymer Laboratories.

The imidization rate of the polyimide was measured as follows. 20 mg of the polyimide powder was placed in an NMR sample tube (NMR sampling tube standard 5 manufactured by Kusano Scientific Co., Ltd.), 1.0 ml of deuterated dimethyl sulfoxide (DMSO-d ₆ , 0.05% TMS mixture) was added and completely dissolved by applying ultrasonic waves . This solution was subjected to proton NMR measurement at 500 MHz using an NMR meter (JNW-ECA500) manufactured by Nippon DATUM Co., The proton derived from the structure which does not change before and after the imidization is defined as a reference proton and the peak integrated value of the proton and the proton peak integrated value derived from the NH group of the amic acid appearing in the vicinity of 9.5 to 10.0 ppm By using the following formula. In the following formula, x is the proton peak integrated value derived from the NH group of the amic acid, y is the peak integrated value of the reference proton, and? Is the NH of the amic acid when the polyamic acid (imidation rate is 0%) Is the ratio of the number of reference protons to one proton of the group.

Imidization ratio (%) = (1 -? X / y) x 100

(Synthesis Example 1)

A solution of BODA (2.0 g, 8.0 mmol), p-PDA (0.87 g, 8.0 mmol), PCH (2.28 g, 6.0 mmol), BEM-S (1.59 g, 6.0 mmol) After reacting at 80 ° C for 5 hours, CBDA (2.31 g, 11.8 mmol) and NMP (9.1 g) were added and reacted at 40 ° C for 10 hours to obtain a polyamic acid solution. NMP was added to the polyamic acid solution (44 g) to dilute it to 6 mass%, acetic anhydride (4.96 g) and pyridine (15.39 g) were added as an imidation catalyst and reacted at 50 ° C for 3 hours. The reaction solution was poured into methanol (590 ml), and the resulting precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100 ° C to obtain a polyimide powder (A). The imidization ratio of the polyimide was 60%, the number average molecular weight was 18,000, and the weight average molecular weight was 29000.

NMP (24.0 g) was added to the obtained polyimide powder (A) (6.0 g), and the mixture was stirred and dissolved at room temperature for 5 hours. NMP (40.0 g) and BCS (30.0 g) were added to this solution and stirred at room temperature for 5 hours to obtain liquid crystal aligning agent (A1).

To 10.0 g of the liquid crystal aligning agent (A1), 60 mg (10% by mass relative to solid content) of a polymerizable compound RM1 was added and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (A2).

Further, to 10.0 g of the liquid crystal aligning agent (A1), 60 mg (10% by mass relative to solid content) of a polymerizable compound RM2 was added and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (A3).

To 10.0 g of the liquid crystal aligning agent (A1), 60 mg (10% by mass relative to solid content) of a polymerizable compound RM3 was added and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent A4.

(Synthesis Example 2)

BMP-S (1.59 g, 6.0 mmol) was added to NMP (26.6 g, 6.0 mmol), TCA (1.79 g, 8.0 mmol), p-PDA (1.08 g, 10.0 mmol) ) And reacted at 80 DEG C for 5 hours. Then, CBDA (2.31 g, 11.8 mmol) and NMP (8.9 g) were added and reacted at 40 DEG C for 10 hours to obtain a polyamic acid solution. NMP was added to the polyamic acid solution (43 g) and diluted to 6 mass%, acetic anhydride (4.84 g) and pyridine (15.0 g) were added as an imidation catalyst and reacted at 50 ° C for 3 hours. The reaction solution was poured into methanol (570 ml), and the obtained precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100 ° C to obtain a polyimide powder (B). The imidization rate of the polyimide was 60%, the number average molecular weight was 21,000, and the weight average molecular weight was 31,000.

NMP (24.0 g) was added to the obtained polyimide powder (B) (6.0 g), and the mixture was stirred and dissolved at room temperature for 5 hours. NMP (40.0 g) and BCS (30.0 g) were added to this solution and stirred at room temperature for 5 hours to obtain liquid crystal aligning agent (B1).

Further, 60 mg (10% by mass relative to solid content) of the polymerizable compound RM3 was added to 10.0 g of the liquid crystal aligning agent (B1) and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (B2).

(Synthesis Example 3)

PDA (0.65 g, 6.0 mmol) and PCH (1.52 g, 4.0 mmol) were mixed in NMP (25.4 g) , And reacted at 80 ° C for 5 hours. Then, CBDA (2.31 g, 11.8 mmol) and NMP (8.5 g) were added and reacted at 40 ° C for 10 hours to obtain a polyamic acid solution. NMP was added to the polyamic acid solution (41 g) to dilute it to 6 mass%, acetic anhydride (4.94 g) and pyridine (15.32 g) as an imidation catalyst were added and reacted at 50 ° C for 3 hours. The reaction solution was poured into methanol (550 ml), and the obtained precipitate was separated by filtration. The precipitate was washed with methanol, and dried at 100 ° C under reduced pressure to obtain a polyimide powder (C). The imidization ratio of the polyimide was 50%, the number average molecular weight was 16,000, and the weight average molecular weight was 21,000.

NMP (24.0 g) was added to the obtained polyimide powder (C) (6.0 g) and dissolved by stirring at room temperature for 5 hours. NMP (40.0 g) and BCS (30.0 g) were added to this solution and stirred at room temperature for 5 hours to obtain liquid crystal aligning agent (C1).

Further, 3.0 g of the liquid crystal aligning agent (A1) and 7.0 g of the liquid crystal aligning agent (C1) were mixed to obtain a liquid crystal aligning agent (C2). To the liquid crystal aligning agent C2 was added 60 mg (10% by mass relative to solid) of a polymerizable compound RM3 and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (C3).

(Synthesis Example 4)

BODA (2.50 g, 10.0 mmol), DADPA (1.99 g, 10.0 mmol), BEM-S (1.59 g, 6.0 mmol) and PCH (1.52 g, 4.0 mmol) were mixed in NMP (28.2 g) After reacting at 80 ° C for 5 hours, CBDA (1.80 g, 9.2 mmol) and NMP (9.41 g) were added and reacted at 40 ° C for 10 hours to obtain a polyamic acid solution. NMP was added to the polyamic acid solution (46 g) to dilute to 6 mass%, acetic anhydride (4.99 g) and pyridine (15.48 g) were added as an imidization catalyst and reacted at 50 ° C for 3 hours. The reaction solution was poured into methanol (610 ml), and the resulting precipitate was separated by filtration. The precipitate was washed with methanol, and dried at 100 ° C under reduced pressure to obtain a polyimide powder (D). The imidization ratio of the polyimide was 50%, the number average molecular weight was 17000, and the weight average molecular weight was 27000.

NMP (24.0 g) was added to the obtained polyimide powder (D) (6.0 g) and dissolved by stirring at room temperature for 5 hours. NMP (40.0 g) and BCS (30.0 g) were added to this solution and stirred at room temperature for 5 hours to obtain a liquid crystal aligning agent (D1).

Further, 3.0 g of the liquid crystal aligning agent (A1) and 7.0 g of the liquid crystal aligning agent (D1) were mixed to obtain a liquid crystal aligning agent (D2). To the liquid crystal aligning agent (D2), 60 mg (10% by mass relative to solid content) of a polymerizable compound RM1 was added and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (D3).

Further, to the liquid crystal aligning agent (D2), 60 mg (10% by mass based on the solid matter) of a polymerizable compound RM2 was added and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (D4).

Further, to the liquid crystal aligning agent (D2), 60 mg (10% by mass relative to solid content) of the polymerizable compound RM3 was added and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (D5).

(Synthesis Example 5)

(1.52 g, 10.0 mmol), m-PDA (0.65 g, 6.0 mmol) and PCH (1.52 g, 4.0 mmol) were mixed in NMP (24.2 g) After reacting at 80 ° C for 5 hours, CBDA (1.88 g, 9.6 mmol) and NMP (8.08 g) were added and reacted at 40 ° C for 10 hours to obtain a polyamic acid solution. NMP was added to the polyamic acid solution (39 g) and diluted to 6 mass%. Acetic anhydride (4.93 g) and pyridine (15.28 g) were added as an imidization catalyst and reacted at 50 ° C for 3 hours. The reaction solution was poured into methanol (520 ml), and the resulting precipitate was separated by filtration. The precipitate was washed with methanol, and dried at 100 ° C under reduced pressure to obtain a polyimide powder (E). The imidization rate of the polyimide was 50%, the number average molecular weight was 19,000, and the weight average molecular weight was 34,000.

NMP (24.0 g) was added to the obtained polyimide powder (E) (6.0 g) and dissolved by stirring at room temperature for 5 hours. NMP (40.0 g) and BCS (30.0 g) were added to this solution and stirred at room temperature for 5 hours to obtain liquid crystal aligning agent (E1).

Further, 3.0 g of the liquid crystal aligning agent (A1) and 7.0 g of the liquid crystal aligning agent (E1) were mixed to obtain a liquid crystal aligning agent (E2). To the liquid crystal aligning agent (E2), 60 mg (10% by mass relative to solid content) of a polymerizable compound RM3 was added and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (E3).

Further, 3.0 g of the liquid crystal aligning agent (B1) and 7.0 g of the liquid crystal aligning agent (E1) were mixed to obtain a liquid crystal aligning agent (E4). To the liquid crystal aligning agent (E4), 60 mg (10% by mass relative to solid content) of a polymerizable compound RM3 was added and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (E5).

(Synthesis Example 6)

(1.50 g, 10.0 mmol), BEM-S (1.59 g, 6.0 mmol) and PCH (1.52 g, 4.0 mmol) were mixed in NMP (27.04 g) After reacting at 80 ° C for 5 hours, CBDA (1.88 g, 9.6 mmol) and NMP (9.01 g) were added and reacted at 40 ° C for 10 hours to obtain a polyamic acid solution. To this polyamic acid solution (44 g) was added NMP and diluted to 6 mass%. Acetic anhydride (4.6 g) and pyridine (14.25 g) were added as an imidization catalyst and reacted at 50 ° C for 3 hours. The reaction solution was poured into methanol (600 ml), and the resulting precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100 ° C to obtain a polyimide powder (F). The imidization ratio of the polyimide was 50%, the number average molecular weight was 21,000, and the weight average molecular weight was 48,000.

NMP (24.0 g) was added to the resulting polyimide powder (F) (6.0 g) and dissolved by stirring at room temperature for 5 hours. NMP (40.0 g) and BCS (30.0 g) were added to this solution and stirred at room temperature for 5 hours to obtain liquid crystal aligning agent (F1).

Further, 3.0 g of the liquid crystal aligning agent (A1) and 7.0 g of the liquid crystal aligning agent (F1) were mixed to obtain a liquid crystal aligning agent (F2). To the liquid crystal aligning agent (F2) was added 60 mg (10% by mass relative to solid content) of a polymerizable compound RM3 and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (F3).

Further, 3.0 g of the liquid crystal aligning agent (B1) and 7.0 g of the liquid crystal aligning agent (F1) were mixed to obtain a liquid crystal aligning agent (F4). To the liquid crystal aligning agent (F4), 60 mg (10% by mass relative to solid content) of a polymerizable compound RM3 was added and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (F5).

(Synthesis Example 7)

DBA (3.04 g, 20.0 mmol) was dissolved in NMP (20.66 g), CBDA (3.84 g, 19.6 mmol) and NMP (6.89 g) were added and reacted at room temperature for 10 hours to obtain a polyamic acid solution. NMP (45.9 g) and BCS (34.4 g) were added to the polyamic acid solution (34 g) and stirred at room temperature for 5 hours to obtain liquid crystal aligning agent (G1). The polyamic acid had a number average molecular weight of 16,000 and a weight average molecular weight of 20,000.

Further, 3.0 g of the liquid crystal aligning agent (A1) and 7.0 g of the liquid crystal aligning agent (G1) were mixed to obtain a liquid crystal aligning agent (G2). To the liquid crystal aligning agent (G2), 60 mg (10% by mass relative to solid content) of a polymerizable compound RM3 was added and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (G3).

(Synthesis Example 8)

(2.84 g, 14.0 mmol) and PCH (2.28 g, 6.0 mmol) were dissolved in NMP (24.77 g), CBDA (3.84 g, 19.6 mmol) and NMP (8.26 g) And reacted for 10 hours to obtain a polyamic acid solution. NMP (55.1 g) and BCS (41.3 g) were added to the polyamic acid solution (40.0 g) and stirred at room temperature for 5 hours to obtain a liquid crystal aligning agent (H1). This polyamic acid had a number average molecular weight of 17,000 and a weight average molecular weight of 23,000.

Further, 3.0 g of the liquid crystal aligning agent (A1) and 7.0 g of the liquid crystal aligning agent (H1) were mixed to obtain a liquid crystal aligning agent (H2). To the liquid crystal aligning agent (H2) was added 60 mg (10% by mass relative to solid content) of a polymerizable compound RM3 and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (H3).

(Synthesis Example 9)

Was dissolved in NMP (22.68 g), CBDA (3.84 g, 19.6 mmol) and NMP (7.56 g) were added, Followed by reaction at room temperature for 10 hours to obtain a polyamic acid solution. NMP (50.39 g) and BCS (37.8 g) were added to the polyamic acid solution (37 g) and stirred at room temperature for 5 hours to obtain liquid crystal aligning agent (I1). The polyamic acid had a number average molecular weight of 19,000 and a weight average molecular weight of 24,000.

Further, 3.0 g of the liquid crystal aligning agent (A1) and 7.0 g of the liquid crystal aligning agent (I1) were mixed to obtain a liquid crystal aligning agent (I2). To the liquid crystal aligning agent (I2), 60 mg (10% by mass relative to solid content) of the polymerizable compound RM3 was added and dissolved by stirring at room temperature for 3 hours to prepare liquid crystal aligning agent (I3).

(Synthesis Example 10)

(3.84 g, 19.6 mmol) was dissolved in NMP (24.3 g), DBA (1.22 g, 8.0 mmol), 3AMPDA (1.45 g, 6.0 mmol) and BEM- And NMP (8.1 g) were added and reacted at room temperature for 10 hours to obtain a polyamic acid solution. NMP (54.0 g) and BCS (40.5 g) were added to the polyamic acid solution (39 g) and stirred at room temperature for 5 hours to obtain liquid crystal aligning agent (J1). This polyamic acid had a number average molecular weight of 12,000 and a weight average molecular weight of 17,000.

Further, 3.0 g of the liquid crystal aligning agent (A1) and 7.0 g of the liquid crystal aligning agent (J1) were mixed to obtain a liquid crystal aligning agent (J2). To the liquid crystal aligning agent J2, 60 mg (10% by mass relative to solid content) of a polymerizable compound RM3 was added and dissolved by stirring at room temperature for 3 hours to prepare liquid crystal aligning agent J3.

&Lt; Production of liquid crystal cell &

(Example 1)

Using the liquid crystal aligning agent (D3) obtained in Synthesis Example 4, a liquid crystal cell was produced in the following order. The liquid crystal aligning agent (D3) obtained in Synthesis Example 4 was spin-coated on the ITO surface of an ITO electrode substrate having an ITO electrode pattern having a pixel size of 100 mu m x 300 mu m and a line / space of 5 mu m, , And then fired in a hot-air circulating oven at 200 ° C for 30 minutes to form a liquid crystal alignment film having a thickness of 100 nm.

The liquid crystal aligning agent D3 was spin-coated on an ITO surface on which no electrode pattern was formed, dried for 90 seconds on a hot plate at 80 占 폚 and fired in a hot air circulating oven at 200 占 폚 for 30 minutes, A liquid crystal alignment film having a thickness of 100 nm was formed.

A 6 占 퐉 bead spacer was dispersed on the liquid crystal alignment film of one of the two substrates, and then a sealing agent (XN-1500T manufactured by Kyoritsu Chemical Co., Ltd.) was printed thereon. Subsequently, the other side of the substrate on the side where the liquid crystal alignment film was formed was inwardly joined with the preceding substrate, and then the sealing agent was cured to prepare empty cells. A negative type liquid crystal (MLC-6608) was injected into this empty cell by a low pressure injection method and subjected to a rearrangement treatment at 120 占 폚 for one hour to prepare a liquid crystal cell 1.

The response speed of the obtained liquid crystal cell 1 was measured by the following method. Thereafter, in a state in which a voltage of 20 Vp-p was applied to the liquid crystal cell 1, UV rays having passed through a band-pass filter of 365 nm from the outside of the liquid crystal cell 1 were irradiated with 20 J. Thereafter, the response speed was again measured, and the response speeds before and after the UV irradiation were compared. The results are shown in Table 2.

The liquid crystal aligning agent D3 was spin-coated on an ITO surface on which no electrode pattern was formed, dried for 90 seconds on a hot plate at 80 占 폚 and fired in a hot air circulating oven at 200 占 폚 for 30 minutes, Two sheets of substrates on which a liquid crystal alignment film with a thickness of 100 nm was formed were prepared, and 6 占 퐉 bead spacers were dispersed on the liquid crystal alignment film of one substrate. Then, a sealant (XN-1500T manufactured by Kyoritsu Chemical Co., Ltd.) . Subsequently, the other side of the substrate on the side where the liquid crystal alignment film was formed was inwardly joined with the preceding substrate, and then the sealing agent was cured to prepare empty cells. A negative type liquid crystal (MLC-6608) was injected into this empty cell by a low-pressure injection method and subjected to a rearrangement treatment at 120 占 폚 for one hour to prepare a liquid crystal cell. From the outside of the liquid crystal cell, UV light having passed through a 365 nm band-pass filter was irradiated with 20 J to obtain a liquid crystal cell 2.

How to measure the response speed

First, the liquid crystal cell 1 prepared above was disposed between a set of polarizers in a measuring apparatus comprising a backlight, a set of polarizers in a crossed Nicol state, and a light amount detector in this order. At this time, the pattern of the ITO electrode in which the line / space was formed was made to have an angle of 45 degrees with respect to Cross-Nicol. Then, a square wave (a rectangular wave) having a voltage of +4 V and a frequency of 1 kHz is applied to the liquid crystal cell 1, a change until the luminance observed by the light amount detector is saturated is injected into the oscilloscope, , And the time required for the brightness to change from 10% to 90% was regarded as the response speed, with a voltage of 0% and a voltage of +4 V applied.

&Quot; Evaluation of residual DC voltage &quot;

A rectangular wave of 30 Hz and 2.8 Vpp superimposed with DC 2 V was applied to the liquid crystal cell 2 prepared above at 23 DEG C for 100 hours, and the voltage (residual DC voltage) remaining in the liquid crystal cell 2 immediately after the DC voltage was applied was applied, Was obtained by the flicker erase method. This value is an index of the afterimage characteristic. When the value is approximately 50 ㎷ or less, it can be said that the afterimage characteristic is excellent.

(Example 2)

The same operation as in Example 1 was carried out except that the liquid crystal aligning agent (D4) was used instead of the liquid crystal aligning agent (D3), and the response speeds before and after UV irradiation were compared. The residual DC voltage was measured.

(Example 3)

The same operation as in Example 1 was carried out except that the liquid crystal aligning agent (D5) was used in place of the liquid crystal aligning agent (D3), and the response speeds before and after UV irradiation were compared. The residual DC voltage was measured.

(Comparative Example 1)

The same operation as in Example 1 was carried out except that the liquid crystal aligning agent (C3) was used in place of the liquid crystal aligning agent (D3), and the response speeds before and after UV irradiation were compared. The residual DC voltage was measured.

(Comparative Example 2)

The same operation as in Example 1 was carried out except that the liquid crystal aligning agent (E3) was used in place of the liquid crystal aligning agent (D3), and the response speeds before and after UV irradiation were compared. The residual DC voltage was measured.

(Example 4)

The same operation as in Example 1 was performed except that the liquid crystal aligning agent (F3) was used in place of the liquid crystal aligning agent (D3), and the response speeds before and after UV irradiation were compared. The residual DC voltage was measured.

(Comparative Example 3)

The same operation as in Example 1 was carried out except that the liquid crystal aligning agent (G3) was used in place of the liquid crystal aligning agent (D3), and the response speeds before and after UV irradiation were compared. The residual DC voltage was measured.

(Comparative Example 4)

The same operation as in Example 1 was carried out except that the liquid crystal aligning agent (H3) was used in place of the liquid crystal aligning agent (D3), and the response speeds before and after UV irradiation were compared. The residual DC voltage was measured.

(Example 5)

The same operation as in Example 1 was carried out except that the liquid crystal aligning agent (I3) was used in place of the liquid crystal aligning agent (D3), and the response speeds before and after UV irradiation were compared. The residual DC voltage was measured.

(Example 6)

The same operation as in Example 1 was performed except that the liquid crystal aligning agent (J3) was used in place of the liquid crystal aligning agent (D3), and the response speeds before and after UV irradiation were compared. The residual DC voltage was measured.

(Comparative Example 5)

The same operation as in Example 1 was performed except that the liquid crystal aligning agent (A2) was used in place of the liquid crystal aligning agent (D3), and the response speeds before and after UV irradiation were compared. The residual DC voltage was measured.

(Comparative Example 6)

The same operation as in Example 1 was performed except that the liquid crystal aligning agent (A3) was used in place of the liquid crystal aligning agent (D3), and the response speeds before and after UV irradiation were compared. The residual DC voltage was measured.

(Comparative Example 7)

The same operation as in Example 1 was carried out except that the liquid crystal aligning agent (A4) was used in place of the liquid crystal aligning agent (D3), and the response speeds before and after UV irradiation were compared. The residual DC voltage was measured.

(Comparative Example 8)

The same operation as in Example 1 was performed except that the liquid crystal aligning agent (B2) was used in place of the liquid crystal aligning agent (D3), and the response speeds before and after UV irradiation were compared. The residual DC voltage was measured.

As shown in Table 2, in Examples 1 to 6 containing both the components (A), (B) and (C), it was possible to sufficiently improve the response speed and suppress the accumulation of residual DC voltage . On the other hand, in Comparative Examples 5 to 8, the response speed was sufficiently improved, but the residual DC voltage was liable to accumulate. In Comparative Examples 1 to 4, the accumulation of the residual DC voltage could be suppressed, but the response speed was not improved well.

Claims (7)

A liquid crystal aligning agent characterized by comprising the following components (A), (B), (C) and an organic solvent.
(A): a photoreactive side chain comprising a side chain for vertically orienting a liquid crystal and at least one member selected from a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group, And a polyimide obtained by imidizing the polyimide precursor, wherein the polyimide precursor is a polyimide precursor.
Component (B): a polymerizable compound having a group capable of photo-polymerization or photo-crosslinking at one or more terminals.
(C): a diamine having a photoreactive side chain comprising at least one member selected from the group consisting of a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group, A polyimide precursor obtained by the reaction of at least one diamine selected from the following (1) to (C-5) with a tetracarboxylic acid dianhydride, and a polyimide obtained by imidizing the polyimide precursor One kind of polymer.
[Chemical Formula 1]

(Wherein Y ₁ represents a secondary amine, a tertiary amine, or a monovalent organic group having a heterocyclic structure, and Y ₂ represents a secondary amine, a tertiary amine, or a divalent organic group having a heterocyclic structure .) The method according to claim 1,
Wherein the photoreactive side chain comprises a group selected from the following formula (I).
(2)

(Wherein R &lt; ¹¹ &gt; is H or a methyl group) 3. The method according to claim 1 or 2,
Wherein the photopolymerization or photo-crosslinking group is selected from the following formula (II).
(3)

(Wherein R ¹² is H or an alkyl group having 1 to 4 carbon atoms, Z ¹ is a bivalent aromatic ring or heterocyclic ring optionally substituted by an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms, and Z ² is a monovalent aromatic ring or heterocyclic ring which may be substituted with an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms. 3. The method according to claim 1 or 2,
The polyimide precursor (C) obtained by using the diamine selected from the formulas (C-1) to (C-5) in an amount of 10 mol% to 80 mol% of the total diamine component , And a polymer selected from polyimides obtained by imidizing the polyimide precursor. A liquid crystal alignment film obtained by applying the liquid crystal aligning agent according to claim 1 or 2 to a substrate and firing the liquid crystal alignment agent. A liquid crystal cell manufactured by applying the liquid crystal aligning agent described in claim 1 or 2 to a substrate and contacting the liquid crystal alignment film obtained by firing to form a liquid crystal layer and irradiating ultraviolet rays while applying a voltage to the liquid crystal layer Wherein the liquid crystal display element is a liquid crystal display element. A liquid crystal cell is produced by irradiating ultraviolet rays while applying a voltage to the liquid crystal layer in contact with a liquid crystal alignment film obtained by applying the liquid crystal aligning agent according to claim 1 or 2 to a substrate and firing Wherein the liquid crystal display element is a liquid crystal display element.