JP6662307B2 - Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display device - Google Patents

Description

  The present invention relates to a liquid crystal aligning agent that can be suitably used for a liquid crystal display device produced by irradiating ultraviolet rays while applying a voltage to liquid crystal molecules, a liquid crystal aligning film formed from the liquid crystal aligning agent, and the liquid crystal. The present invention relates to a liquid crystal display device having an alignment film.

In a liquid crystal display element of a type in which liquid crystal molecules vertically aligned with a substrate are responded by an electric field (also referred to as a vertical alignment (VA) mode), a voltage is applied to the liquid crystal molecules in a manufacturing process. While irradiating with ultraviolet rays.
In such a vertical alignment type liquid crystal display device (such as a PSA (Polymer Sustained Alignment) type liquid crystal display), a photopolymerizable compound is added in advance to a liquid crystal composition, and the liquid crystal cell is used together with a vertical alignment film such as polyimide to apply a voltage to a liquid crystal cell. A technique is known in which the response speed of a liquid crystal is increased by irradiating ultraviolet rays while applying a voltage (see Patent Document 1 and Non-Patent Document 1).

Normally, the tilt direction of liquid crystal molecules in response to an electric field is controlled by a projection provided on a substrate or a slit provided on a display electrode, but a photopolymerizable compound is added to the liquid crystal composition. By irradiating ultraviolet rays while applying a voltage to the liquid crystal cell, a polymer structure in which the tilted direction of the liquid crystal molecules is stored is formed on the liquid crystal alignment film. It is said that the response speed of the liquid crystal display element is faster than the method of controlling the response.
In addition, it has been reported that the response speed of a liquid crystal display element can be increased by adding a photopolymerizable compound not to a liquid crystal composition but to a liquid crystal alignment film (SC-PVA liquid crystal display) (Non-Patent Document 1). Patent Document 2).

JP-A-2003-307720.

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

  In recent years, it has been desired that the response speed of the liquid crystal display device be further increased, and it is conceivable to increase the response speed of the liquid crystal display device by increasing the addition amount of the photopolymerizable compound. The photopolymerizable compound has a property that it is difficult to dissolve in a solvent used for a liquid crystal alignment agent. Therefore, when the liquid crystal aligning agent is stored, a problem of storage stability that the photopolymerizable compound is precipitated occurs. Also, when the liquid crystal display element is exposed to a temperature change during the manufacturing process, a part of the polymerizable compound may be eluted from the liquid crystal alignment film into the liquid crystal, or may be crystallized in the liquid crystal. There is. In particular, when the solubility of the polymerizable compound in the liquid crystal is low, crystallization in the liquid crystal is likely to occur. Such crystallization of the polymerizable compound in the liquid crystal serves as a bright spot source in a display device, leading to a reduction in display quality of the device.

Another problem of the liquid crystal display element is burn-in (afterimage), which may occur when the same pattern is displayed for a long time. One of the causes of this burn-in is due to charge accumulation. Burn-in caused by accumulation of electric charges is also called DC burn-in, but can be suppressed to some extent by driving applying a voltage of which polarity is inverted, that is, by polarity inversion driving. On the other hand, even if the pretilt angle changes slightly, burn-in occurs. When the pretilt angle changes, the VT characteristics are affected, so that the transmittance changes even when the same voltage is applied. Since the applied voltage at the time of white display is different from the applied voltage at the time of black display, the amount of change in the tilt angle differs according to the applied voltage. Burn-in may be recognized. Such image sticking cannot be suppressed even by performing the polarity inversion drive, and is also called AC image sticking.
An object of the present invention is to solve the above-mentioned problems of the conventional technology.

（式中、Ｘ^１及びＸ^２は、それぞれ独立して、エーテル結合及びエステル結合から選ばれる結合基を表し、Ｓ^１及びＳ^２は、それぞれ独立して、炭素数２〜９の直鎖アルキレン基を表し、かつ、当該Ｓ^１、Ｘ^１、Ｘ^２及びＳ^２は、分子が左右非対称となるように選択されてなる。）The inventors of the present invention have conducted studies to achieve the above object, and as a result, the present invention has the following gist.
1. A liquid crystal aligning agent containing a polymerizable compound represented by the following formula (1) and at least one polymer selected from the group consisting of a polyimide precursor and a polyimide.

(Wherein, X ¹ and X ² each independently represent a bonding group selected from an ether bond and an ester bond, and S ¹ and S ² each independently represent a straight-chain alkylene having 2 to 9 carbon atoms. Represents a group, and said S ¹ , X ¹ , X ² and S ² are selected such that the molecule is bilaterally asymmetric.)

2. ^2. The liquid crystal aligning agent according to the above 1, wherein in the polymerizable compound (1), S ¹ and S ² are alkylene groups having different carbon numbers.
3. In the polymerizable compound (1), one of X ¹ and X ² is an ether bond and the other is an ester bond, or X ¹ is an ester bond bonded to S ¹ on the carbonyl side, and X ² is the liquid crystal aligning agent according to the above 1 or 2 is an ester group bonded to S ² oxygen atoms side.
4. 4. The liquid crystal aligning agent according to any one of the above 1 to 3, wherein at least one polymer selected from the group consisting of a polyimide precursor and a polyimide has a side chain that vertically aligns the liquid crystal.
5. The liquid crystal alignment agent according to any one of the above items 1 to 4, wherein at least one polymer selected from the group consisting of a polyimide precursor and a polyimide further has a photoreactive side chain.
6. A liquid crystal alignment film comprising the liquid crystal alignment agent according to any one of the above 1 to 5.
7. 7. A liquid crystal display device having the liquid crystal alignment film according to the above item 6.

（式中、Ｘ^１及びＸ^２は、それぞれ独立して、エーテル結合及びエステル結合から選ばれる結合基を表し、Ｓ^１及びＳ^２は、それぞれ独立して、炭素数２〜９の直鎖アルキレン基を表し、かつ、当該Ｓ^１、Ｘ^１、Ｘ^２及びＳ^２は、分子が左右非対称となるように選択される。）8. A liquid crystal aligning agent containing at least one polymer selected from the group consisting of a polyimide precursor and a polyimide is applied on two substrates to form a liquid crystal alignment layer. A method for manufacturing a vertical alignment type liquid crystal display element, comprising: arranging two substrates, sandwiching a liquid crystal layer between the two substrates, and irradiating ultraviolet rays while applying an electric field to the liquid crystal layer,
A method for producing a liquid crystal display device, characterized in that at least one of a liquid crystal aligning agent and a liquid crystal layer contains a polymerizable compound represented by the formula (1).

(Wherein, X ¹ and X ² each independently represent a bonding group selected from an ether bond and an ester bond, and S ¹ and S ² each independently represent a straight-chain alkylene having 2 to 9 carbon atoms. Represents a group and said S ¹ , X ¹ , X ² and S ² are selected such that the molecule is bilaterally asymmetric.)

9. The method according to the above item 8, wherein in the polymerizable compound (1), S ¹ and S ² are alkylene groups having different carbon numbers.
10. The polymerizable compound (1), either one of X ¹ and X ² is an ether bond, or the other is an ester bond, an ester bond which X ¹ binds S ¹ carbonyl side, X ² Is the ester group bonded to S ² on the oxygen atom side, wherein
11. The method according to any one of the above items 8 to 10, wherein at least one polymer selected from the group consisting of a polyimide precursor and a polyimide has a side chain for vertically aligning the liquid crystal.
12. 12. The production method according to any one of 8 to 11, wherein at least one polymer selected from the group consisting of a polyimide precursor and a polyimide further has a photoreactive side chain.

（式中、Ｘ^１及びＸ^２は、それぞれ独立して、エーテル結合及びエステル結合から選ばれる結合基を表し、Ｓ^１及びＳ^２は、それぞれ独立して、炭素数２〜９の直鎖アルキレン基を表し、かつ、Ｓ^１、Ｘ^１、Ｘ^２及びＳ^２は、分子が左右非対称となるように選択される。）13. A polymerizable compound represented by the following formula (1).

(Wherein, X ¹ and X ² each independently represent a bonding group selected from an ether bond and an ester bond, and S ¹ and S ² each independently represent a straight-chain alkylene having 2 to 9 carbon atoms. Represents a group, and S ¹ , X ¹ , X ² and S ² are selected such that the molecule is bilaterally asymmetric.)

14． 14. The polymerizable compound according to the above 13, wherein in the formula (1), S ¹ and S ² are alkylene groups having different carbon numbers.
15. In the formula (1), ^one of X ¹ and X ² is an ether bond and the other is an ester bond, or X ¹ is an ester bond bonded to S ¹ on the carbonyl side, and X ² is an oxygen atom an ester group bonded to S ² at the side, the polymerizable compound according to the above 13 or 14.

  According to the present invention, a novel polymerizable compound containing a liquid crystal aligning agent and / or a liquid crystal layer contains a novel polymerizable compound capable of providing a liquid crystal display device having a high response speed and excellent afterimage characteristics derived from AC. A liquid crystal aligning agent, a liquid crystal aligning film formed using the liquid crystal aligning agent, and a device having a high response speed, particularly, a vertical alignment method can be obtained.

式（１）中、Ｘ^１、Ｘ^２、Ｓ^１、及びＳ^２の定義は、それぞれ上記したとおりである。なかでも、Ｓ^１及びＳ^２は、それぞれ独立して、炭素数２〜６の直鎖アルキレン基が好ましい。<Polymerizable compound>
The polymerizable compound contained in the liquid crystal alignment agent of the present invention is represented by the following formula (1).

In the formula (1), the definitions of X ¹ , X ² , S ¹ , and S ² are as described above. Among them, S ¹ and S ² are preferably each independently a straight-chain alkylene group having 2 to 6 carbon atoms.

As a preferable method for causing S ¹ , X ¹ , X ² and S ² to have a bilaterally asymmetric molecule, a method of selecting an alkylene group in which S ¹ and S ² have mutually different carbon numbers (method 1) and a method of selecting a bonding group in which X ¹ and X ² are asymmetrical to each other (method 2). Here, the method 1 and the method 2 can be used in combination.
The method 2, specifically, the one ether bond X ¹ and X ^2, a method of the other ester bonds (2-1), which binds to S ¹ and X ¹ carbonyl side ester A method (method 2-2) of forming a bond and converting X ² to an ester group bonded to S ² on the oxygen atom side.
Among such compounds, compounds having an alkylene group having different carbon numbers can be obtained by the production method described in International Patent Application Publication No. WO2012 / 002513. When it is desired that one is an ether bond and the other is an ester bond, 4- (4-hydroxyphenyl) benzoic acid is used as a raw material instead of bisphenol in the production method described in International Patent Application Publication No. WO2012 / 002513. What is necessary is just to manufacture using it.

As a method for making the molecule bilaterally asymmetric, in addition to the above methods 1 and 2, a method in which the left and right polymerizable groups are different (method 3), and a substituent is introduced so that the benzene ring becomes bilaterally asymmetric. (Method 4).
By selecting at least one method selected from the above methods 1 and 2, the solubility of the polymerizable compound is improved, and the after-image characteristics derived from AC are lower than when the methods 3 and 4 are selected. It turned out to be excellent. Although the reason for this is not clear, it is thought that the afterimage characteristics derived from AC are caused by stacking of the ring structure of the polymerizable compound. However, when Method 1 or Method 2 is selected, Method 3 or Method 4 is used. It is considered that stacking is not inhibited as compared with the case where the selection is made.

<Polymer from polyimide precursor and / or polyimide>
In a liquid crystal display element formed by being contained in a liquid crystal aligning agent and / or a liquid crystal layer, at least one polymer selected from the group consisting of a polyimide precursor and a polyimide (hereinafter also referred to as a specific polymer) which is preferably used. A known polyimide precursor or polyimide used as a liquid crystal aligning agent can be used. The polyimide precursor specifically includes a polyamic acid and a polyamic acid ester.

  The polyimide precursor or the polyimide which is a specific polymer preferably has a side chain (I) for vertically aligning the liquid crystal for a PSA-type liquid crystal display, and has a vertical chain for an SC-PVA type liquid crystal display. It is preferable to have a photoreactive side chain (II) in addition to the side chain (I) to be orientated.

<Side chain (I) for vertically aligning liquid crystal>
The side chain (I) (hereinafter, also referred to as side chain A) for vertically aligning the liquid crystal is a side chain having the ability to align the liquid crystal molecules vertically to the substrate. The structure is not limited. As such a side chain, for example, a long-chain alkyl group, a fluoroalkyl group, a cyclic group having an alkyl group or a fluoroalkyl group at a terminal, a steroid group, and the like are known, and are suitably used in the present invention. These groups may be directly bonded to the main chain of the specific polymer or may be bonded via an appropriate bonding group, as long as they have the above-mentioned ability.

Examples of the side chain A include those represented by the following formula (a).
In the formula (a), l, m and n each independently represent an integer of 0 or 1, and R ¹ is an alkylene group having 1 to 6 carbon atoms, —O—, —COO—, and —OCO—. _{, -NH -, - NHCO -,} - CONH -, - COOCH 2 -, - CH 2 OCO -, - CH 2 COO -, - OCOCH 2 - or alkylene of 1 to 3 carbon atoms - an ether group. R ² , R ³ and R ⁴ each independently represent a phenylene group or a cycloalkylene group, and R ⁵ is a hydrogen atom, an alkyl group having 1 to 24 carbon atoms, an alkoxy group having 1 to 24 carbon atoms, and a carbon atom having 1 carbon atom. To 24 fluorine-containing alkyl groups, 1 to 24 carbon-containing fluorine-containing alkoxy groups, fluorine groups, cyano groups, nitro groups, azo groups, formyl groups, acetyl groups, acetoxy groups, hydroxyl groups, aromatic rings, aliphatic rings, and heterocyclic groups Represents a ring or a macrocyclic substituent composed thereof.

R ¹ is preferably -O-, -COO-, -CONH-, or an alkylene ether group having 1 to 3 carbon atoms from the viewpoint of ease of synthesis.
R ² , R ³ and R ⁴ are represented by the following combinations of l, m, n, R ² , R ³ and R ⁴ shown in Table 1 from the viewpoint of easiness of synthesis and ability to vertically align liquid crystals. preferable.

[Table 1]
_______________________________________________
lmn R ² R ³ R ⁴
_______________________________________________
1 1 1 phenylene phenylene cyclohexylene 1 1 1 phenylene cyclohexylene cyclohexylene 1 1 1 cyclohexylene cyclohexylene cyclohexylene 1 10 phenylene phenylene-
110 phenylene cyclohexylene-
_______________________________________________

When at least one of l, m and n is 1, R ⁵ is preferably a hydrogen atom, an alkyl group having 2 to 14 carbon atoms or a fluorine-containing alkyl group having 2 to 14 carbon atoms, and more preferably hydrogen. An atom, an alkyl group having 2 to 12 carbon atoms or a fluorine-containing alkyl group having 2 to 12 carbon atoms. When l, m, and n are both 0, R ⁵ is preferably an alkyl group having 12 to 22 carbon atoms, a fluorine-containing alkyl group having 12 to 22 carbon atoms, an aromatic ring, an aliphatic ring, or a heterocyclic ring. Or a macrocyclic substituent comprising them, more preferably an alkyl group having 12 to 20 carbon atoms or a fluorine-containing alkyl group having 12 to 20 carbon atoms.

  The ability to vertically align the liquid crystal depends on the structure of the side chain A described above, but generally, the ability to vertically align the liquid crystal increases when the amount of the side chain A contained in the polymer increases, and decreases when the amount decreases. Go down. Further, the side chain A having a cyclic structure tends to vertically align the liquid crystal even with a small content as compared with the side chain A of the long-chain alkyl group.

  The amount of the side chain A in the specific polymer is not particularly limited as long as the liquid crystal alignment film is in a range where the liquid crystal can be vertically aligned. However, in a liquid crystal display device having a liquid crystal alignment film, when it is desired to increase the response speed of liquid crystal, the content of the side chain A is preferably as small as possible within a range where vertical alignment can be maintained.

<Photoreactive side chain (II)>
The photoreactive side chain (II) (hereinafter, also referred to as side chain B) is a crosslinkable side chain having a functional group (hereinafter, also referred to as a photocrosslinking group) capable of forming a covalent bond by reacting with ultraviolet irradiation. Or a photoradical-generating side chain having a functional group capable of generating a radical upon irradiation with ultraviolet light, and its structure is not limited as long as it has this ability.
As such a side chain, for example, a side chain containing a vinyl group, an acryl group, a methacryl group, an anthracenyl group, a cinnamoyl group, a chalconyl group, a coumarin group, a maleimide group, a stilbene group or the like as a photocrosslinking group is known. In the present invention, it is suitably used. Examples of the structure that generates a radical upon irradiation with ultraviolet light include an acylphosphine oxide structure, an acetophenone structure, an alkylpenone structure, an anthraquinone structure, a carbazole structure, a xanthone structure, a thioxanthone structure, a triphenylamine structure, a fluorenone structure, a benzaldehyde structure, and a benzoin structure. Examples thereof include a benzophenone structure and a fluorene structure, and a photoradical generating side chain having these structures is also preferably used. Among them, a side chain having an acetophenone structure, a benzophenone structure, or a benzoin structure is preferable.
These groups may be directly bonded to the main chain of the specific polymer or may be bonded via an appropriate bonding group, as long as they have the above-mentioned ability.

  Examples of the side chain B include the following formulas (b-1) to (b-3). The side chain represented by the formula (b-2) has a structure having a cinnamoyl group and a methacryl group, and the side chain represented by the formula (b-3) has a structure that generates a radical by irradiation with ultraviolet light. Having.

In the formula (b-1), R ⁶ represents —CH ₂ —, —O—, —COO—, —OCO—, —NHCO—, —CONH—, —NH—, —CH ₂ O—, —N (CH _{3) -, - CON (CH} 3) -, or -N _(CH 3) a CO-. From the viewpoint of ease of synthesis, R ⁶ is preferably —CH ₂ —, —O—, —COO—, —NHCO—, —NH—, or —CH ₂ O—.

R ⁷ represents an alkylene group having 1 to 20 carbon atoms which is cyclic, unsubstituted or substituted by a fluorine atom, and any —CH ₂ — in the alkylene group is replaced by —CF ₂ — or —CH ＝ CH—. And when any of the following groups are not adjacent to each other, they may be replaced by these groups; -O-, -COO-, -OCO-, -NHCO-, -CONH- , -NH-, a carbocyclic ring, or a heterocyclic ring.
Specific examples of the carbocycle and the heterocycle include, but are not limited to, the following structures.

R ⁸ _{is, -CH 2 -, - O -} , - CH 2 O -, - COO -, - OCO -, - NH -, - CONH -, - NHCO -, - N (CH 3) -, - CON ( CH ₃ ) —, —N (CH ₃ ) CO—, a carbocyclic ring, or a heterocyclic ring. From _the viewpoint of ease of synthesis, -CH 2 -, - O - , - COO -, - OCO-, NHCO -, - NH-, carbocyclic, or heterocyclic ring. Specific examples of the carbocycle and the heterocycle are as described above.

R ⁹ is a styryl group, —CR ¹⁸ ＣＨCH ₂ group, a carbocyclic ring, a heterocyclic ring, or the following formulas (R9-1) to (R9-34), and R ¹⁸ is substituted with a hydrogen atom or a fluorine atom. Represents an optionally substituted methyl group.

Among them, from the viewpoint of photoreactivity, as R ⁹ , a styryl group, —CH ＝ CH ₂ , —C (CH ₃ ) ＝ CH _2, or the above (R9-2), (R9-12) or (R9 -15) is more preferred.

In the formula (b-2), R ¹⁰ is —CH ₂ —, —O—, —CONH—, —NHCO—, —COO—, —OCO—, —NH—, or —CO—.
R ¹¹ is an alkylene group having 1 to 30 carbon atoms, a divalent carbocycle or a divalent heterocycle, wherein at least one hydrogen atom of the alkylene group, the divalent carbocycle and the divalent heterocycle is fluorine. It may be replaced by an atom or an organic group. In the case where any of the following groups are not adjacent to each other, any of —CH ₂ — in R ¹¹ may be replaced by these groups; —O—, —NHCO—, and —CONH —, —COO—, —OCO—, —NH—, —NHCONH—, or —CO—.
R ¹² is —CH ₂ —, —O—, —CONH—, —NHCO—, —COO—, —OCO—, —NH—, —CO—, or a single bond.
R ¹³ is a cinnamoyl group, a chalcone group, or a coumarin group, and represents a photocrosslinking group.
R ¹⁴ is a single bond, an alkylene group having 1 to 30 carbon atoms, a divalent carbocycle or a divalent heterocycle, and at least one hydrogen atom of the alkylene group, the divalent carbocycle and the divalent heterocycle May be replaced by a fluorine atom or an organic group. In the case where any of the following groups are not adjacent to each other, any of —CH ₂ — in R ¹⁴ may be replaced by these groups; —O—, —NHCO—, and —CONH —, —COO—, —OCO—, —NH—, —NHCONH—, or —CO—.
R ¹⁵ is an acryl group or a methacryl group, and represents a photopolymerizable group.
Of the side chain represented by the formula ^(b-2), specific examples of the group represented by ^{-R 13} -R 14 -R ^15, it may be mentioned the following structures, but not limited to. In the following structures, R represents a hydrogen atom or a methyl group.

In the formula (b-3), Ar ₄ represents an aromatic hydrocarbon group selected from phenylene, naphthylene, and biphenylene, and these groups may be substituted by an organic group, and a hydrogen atom of these groups May be substituted with a halogen atom.
R ₁₆ and _{R 17} are each independently an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a benzyl group, or phenethyl group, the alkyl group and alkoxy _group, and _{R 16} R ₁₇ may form a ring.
T ₁ and T ₂ are each independently a single bond, —O—, —COO—, —OCO—, —NHCO—, —CONH—, —NH—, —CH ₂ O—, —N (CH _{3 ) -, - CON (CH 3} ) - or -N _(CH 3) shows a binding group CO-.
S ⁴ represents an alkylene group having 1 to 20 carbon atoms which is a single bond, unsubstituted or substituted by a fluorine atom (provided that -CH ₂ -or -CF _{2-in the} alkylene group is -CH = CH- It may be arbitrarily substituted, and when any of the groups listed below are not adjacent to each other, they may be substituted with -O-, -COO-, -OCO-, -NHCO-. , -CONH-, -NH-, a divalent carbocycle, or a divalent heterocycle.).
n2 represents 0 or 1. Q represents a structure represented by the following formula.

（式中、Ｒは水素原子又は炭素数１〜４のアルキル基を表し、Ｒ_３は−ＣＨ_２−、−ＮＲ−、−Ｏ−、又は−Ｓ−を表す）

(In the formula, R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ₃ represents —CH ₂ —, —NR—, —O—, or —S—)

Of the side chain represented by the formula _(b-3), specific examples of the group represented by ^{-Ar 4 -CO-CQR 16 R 17} , the following formulas (b-3-1) ~ (b- Although the structure of 3-6) can be mentioned, it is not limited to these.

The amount of the side chain B in the specific polymer is not particularly limited as long as the response speed of the liquid crystal in the liquid crystal display device can be increased. When it is desired to increase the response speed of the liquid crystal in the liquid crystal display element, it is preferable to increase the liquid crystal display element as much as possible without affecting other characteristics.
<Polyimide precursor>
The polyimide precursor means polyamic acid and polyamic acid ester. Hereinafter, a method for preparing a polyamic acid will be described. The polyamic acid ester can be prepared by a conventionally known method or a method similar to or similar to the polyamic acid described below.

<Polyamic acid>
The polyamic acid having the side chain A is obtained by reacting the raw material, either of the diamine and the tetracarboxylic anhydride, which are the raw materials, having either the side chain A or both having the side chain A. be able to. Among these, a method using a diamine having a side chain A is preferable from the viewpoint of easiness of raw material synthesis.

  In addition, the polyamic acid having the side chain A and the side chain B is such that only one of the diamine and the tetracarboxylic anhydride as raw materials has the side chain A and the side chain B, or one of the side chains has the side chain. A only, and the other has only the side chain B, or either one has the side chain A and the side chain B, and the other has the side chain A, or either one has the side chain A and Having the side chain B and the other having the side chain B, or having both the side chain A and the side chain B, it can be obtained by reacting the raw materials. Among these, it is preferable that the side chain A and the side chain B are contained only in the diamine from the viewpoint of easiness of raw material synthesis.

<Diamine having side chain A>
Examples of the diamine having a side chain A (hereinafter, referred to as diamine A) include a diamine having an alkyl group, a fluorine-containing alkyl group, an aromatic ring, an aliphatic ring, a heterocyclic ring, or a macrocyclic substituted product thereof on the diamine side chain. Can be mentioned as an example. Specifically, a diamine having a side chain represented by the formula (a) can be mentioned. More specifically, diamines represented by the following formulas (1), (3), (4), and (5) can be given, but are not limited thereto. The definitions of l, m, n, and R ^{1 to} R ^{5 in} the formula (1) are the same as those in the formula (a).

式（３）及び式（４）中、Ａ_１０は、各々独立に、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＮＨ−、−ＮＨＣＯ−、−ＣＨ_２−、−Ｏ−、−ＣＯ−、又は−ＮＨ−を表し、Ａ_１１は単結合若しくはフェニレン基を表し、ａは側鎖Ａを表し、ａ’はアルキル基、フッ素含有アルキル基、芳香環、脂肪族環、複素環、又はこれらから選ばれる任意の構造の組み合わせからなる大環状置換体を表す。

In the formulas (3) and (4), A ₁₀ is each independently —COO—, —OCO—, —CONH—, —NHCO—, —CH ₂ —, —O—, —CO—, or —. A represents NH—, A ₁₁ represents a single bond or a phenylene group, a represents a side chain A, and a ′ is selected from an alkyl group, a fluorine-containing alkyl group, an aromatic ring, an aliphatic ring, a heterocyclic ring, or these. It represents a macrocyclic substituent consisting of any combination of structures.

式（５）中、Ａ_１４は、フッ素原子で置換されていてもよい、炭素数３〜２０のアルキル基であり、Ａ_１５は、１，４−シクロへキシレン基、又は１，４−フェニレン基であり、Ａ_１６は、酸素原子、又は−ＣＯＯ−＊（ただし、「＊」を付した結合手がＡ_３と結合する）であり、Ａ_１７は酸素原子、又は−ＣＯＯ−＊（ただし、「＊」を付した結合手が（ＣＨ_２）ａ_２と結合する。）である。また、ａ_１は０、又は１の整数であり、ａ_２は２〜１０の整数であり、ａ_３は０、又は１の整数である。）

In the formula (5), A ₁₄ is an alkyl group having 3 to 20 carbon atoms which may be substituted by a fluorine atom, and A ₁₅ is a 1,4-cyclohexylene group or 1,4-phenylene A ₁₆ is an oxygen atom or —COO- * (where the bond with “*” is bonded to A ₃ ), and A ₁₇ is an oxygen atom or —COO- * (where , The bond with “*” bonds to (CH ₂ ) a _2. ). A ₁ is an integer of 0 or 1, a ₂ is an integer of ₂ to 10, and a ₃ is an integer of 0 or 1. )

The bonding position of the two amino groups (—NH ₂ ) in the formula (1) is not limited. Specifically, with respect to the bonding group in the side chain, the positions of 2, 3 on the benzene ring, the positions of 2, 4, the positions of 2, 5, the positions of 2, 6, the positions of 3, 4, and 3, 5 positions. Among them, the 2,4 position, the 2,5 position, or the 3,5 position are preferred from the viewpoint of reactivity when synthesizing the polyamic acid. Taking into account the easiness in synthesizing the diamine, the positions of 2, 4 or 3, 5 are more preferable.

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

In the formulas [A-1] to [A-5], A ₁ is an alkyl group having 2 to 24 carbon atoms or a fluorine-containing alkyl group having 2 to 24 carbon atoms.
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 having 1 to 22 carbon atoms, a fluorine-containing alkyl group having 1 to 22 carbon atoms, or a fluorine-containing alkoxy group having 1 to 22 carbon atoms.
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 —, wherein A ₅ is an alkyl group having 1 to 22 carbon atoms, an alkoxy group having 1 to 22 carbon atoms, a fluorine-containing alkyl group having 1 to 22 carbon atoms, or a carbon number. 1 to 22 fluorine-containing alkoxy groups.

式［Ａ−１１］及び式［Ａ−１２］中、Ａ_６は、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＮＨ−、−ＮＨＣＯ−、−ＣＯＯＣＨ_２−、−ＣＨ_２ＯＣＯ−、−ＣＨ_２Ｏ−、−ＯＣＨ_２−、−ＣＨ_２−、−Ｏ−、又は−ＮＨ−を示し、Ａ_７は、フッ素基、シアノ基、トリフルオロメタン基、ニトロ基、アゾ基、ホルミル基、アセチル基、アセトキシ基又は水酸基である。
式［Ａ−１３］及び式［Ａ−１４］中、Ａ_８は、炭素数３〜１２のアルキル基であり、１,４-シクロヘキシレンのシス−トランス異性は、それぞれトランス異性体である。
式［Ａ−１５］及び式［Ａ−１６］中、Ａ_９は、炭素数３〜１２のアルキル基であり、１,４-シクロヘキシレンのシス−トランス異性は、それぞれトランス異性体である。

In the formulas [A-11] and [A-12], A ₆ represents —COO—, —OCO—, —CONH—, —NHCO—, —COOCH ₂ —, —CH ₂ OCO—, —CH ₂ O —, —OCH ₂ —, —CH ₂ —, —O—, or —NH—, and A ₇ represents a fluorine group, a cyano group, a trifluoromethane group, a nitro group, an azo group, a formyl group, an acetyl group, an acetoxy group. Or a hydroxyl group.
Wherein [A-13] and the formula _[A-14], A ₈ is an alkyl group having 3 to 12 carbon atoms, 1,4-cyclohexylene cis - trans isomers are each trans isomer.
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.

（Ａ_１２は、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＮＨ−、−ＮＨＣＯ−、−ＣＨ_２−、−Ｏ−、−ＣＯ−、又は−ＮＨ−を示し、Ａ_１３は、炭素数１〜２２のアルキル基又は炭素数１〜２２のフッ素含有アルキル基を示す。）Specific examples of the diamine represented by the formula (3) include, but are not limited to, diamines represented by the following formulas [A-25] to [A-30].

_(A 12 are, -COO -, - OCO -, - CONH -, - NHCO -, - CH 2 -, - O -, - CO-, or -NH- are _{shown, A 13} is 1 to 22 carbon atoms Or a fluorine-containing alkyl group having 1 to 22 carbon atoms.)

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

Among them, [A-1], [A-2], [A-3], [A-7], [A-14], and [A-1], [A-2], [A-3], from the viewpoint of the ability to vertically align the liquid crystal and the response speed of the liquid crystal. The diamine of [A-16], [A-21] or [A-22] is preferred.
One of the above diamines may be used alone, or two or more of them may be used in combination depending on characteristics such as liquid crystal alignment, pretilt angle, voltage holding characteristics, and accumulated charge when a liquid crystal alignment film is formed.

  Of the diamine component 100 mol% used for the synthesis of the polyamic acid having the side chain A, the diamine A is 5 to 70 mol%, preferably 10 to 50 mol%, and more preferably 20 to 50 mol%. .

<Diamine having side chain B>
Examples of the diamine having a side chain B (hereinafter also referred to as diamine B) include a diamine side chain having a vinyl group, an acryl group, a methacryl group, an anthracenyl group, a cinnamoyl group, a carconyl group, a coumarin group, a maleimide group, a stilbene group, or the like. Examples thereof include a diamine having a photocrosslinking group and a diamine having a functional group that generates a radical upon irradiation with ultraviolet light. Specifically, diamines having side chains represented by the formulas (b-1) to (b-3) can be mentioned. As a specific example, a diamine represented by the following general formula (2) (the definitions of R ⁶ , R ⁷ , R ⁸ and R ^{9 in} the formula (2) are the same as those in the formula (b-1)) But not limited thereto.

式（２）中における二つのアミノ基（−ＮＨ_２）の結合位置は、特に限定されない。具体的には、側鎖の結合基に対して、ベンゼン環上の２，３の位置、２，４の位置、２，５の位置、２，６の位置、３，４の位置、３，５の位置が挙げられる。なかでも、ポリアミック酸を合成する際の反応性の観点から、２，４の位置、２，５の位置、又は３，５の位置が好ましい。ジアミンを合成する際の容易性も加味すると、２，４の位置、又は３，５の位置がより好ましい。

Coupling position of the formula (2) two amino groups in (-NH ₂₎ is not particularly limited. Specifically, with respect to the bonding group in the side chain, the positions of 2, 3 on the benzene ring, the positions of 2, 4, the positions of 2, 5, the positions of 2, 6, the positions of 3, 4, and 3, 5 positions. Among them, the 2,4 position, the 2,5 position, or the 3,5 position are preferred from the viewpoint of reactivity when synthesizing the polyamic acid. Taking into account the easiness in synthesizing the diamine, the positions of 2, 4 or 3, 5 are more preferable.

Specific examples include the following compounds, but are not limited thereto. In the following compounds, X represents a bonding group selected from the group consisting of ether, ester, amide and amino, R represents a hydrogen atom or a methyl group, and S ³ represents a single bond, or an unsubstituted or fluorine atom. It represents a substituted alkylene group having 1 to 20 carbon atoms. In addition, l, m, and n each independently represent an integer of 0 to 20.

  One or two kinds of the above-described diamines are used depending on the liquid crystal alignment property when forming a liquid crystal alignment film, pretilt angle, voltage holding properties, characteristics such as accumulated charge, and the response speed of liquid crystal when forming a liquid crystal display element. The above may be used in combination.

  Of the diamine component 100 mol% used for the synthesis of the polyamic acid, diamine B is 0 to 95 mol%, preferably 20 to 80 mol%, more preferably 40 to 70 mol%.

<Other diamines>
The polyamic acid used in the present invention is a diamine component other than a diamine having a side chain for vertically aligning the liquid crystal and a diamine having a photoreactive group, as long as the effects of the present invention are not impaired. Can be used together. Specifically, p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, m-phenylenediamine, 2,4-dimethyl-m- Phenylenediamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,5-diaminophenol, 2,4-diaminophenol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4- Diaminobenzyl alcohol, 4,6-diaminoresorcinol, 4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, , 3'-dihydroxy-4,4'-diaminobiphenyl, 3,3'-dicarboxy-4,4'-diaminobiphenyl, , 3'-Difluoro-4,4'-biphenyl, 3,3'-trifluoromethyl-4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,2 ' -Diaminobiphenyl, 2,3'-diaminobiphenyl, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 2,2'-diaminodiphenylmethane, 2,3'-diamino Diphenylmethane, 4,4'-diaminodiphenylether, 3,3'-diaminodiphenylether, 3,4'-diaminodiphenylether, 2,2'-diaminodiphenylether, 2,3'-diaminodiphenylether, 4,4'-sulfonyldianiline , 3,3'-sulfonyldianiline, bis (4-aminophenyl) silane, (3-aminophenyl) silane, dimethyl-bis (4-aminophenyl) silane, dimethyl-bis (3-aminophenyl) silane, 4,4'-thiodianiline, 3,3'-thiodianiline, 4,4'- Diaminodiphenylamine, 3,3′-diaminodiphenylamine, 3,4′-diaminodiphenylamine, 2,2′-diaminodiphenylamine, 2,3′-diaminodiphenylamine, N-methyl (4,4′-diaminodiphenyl) amine, N -Methyl (3,3'-diaminodiphenyl) amine, N-methyl (3,4'-diaminodiphenyl) amine, N-methyl (2,2'-diaminodiphenyl) amine, N-methyl (2,3'- Diaminodiphenyl) amine, 4,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, 3,4'-diamine Benzophenone, 1,4-diaminonaphthalene, 2,2'-diaminobenzophenone, 2,3'-diaminobenzophenone, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 1,8- Diaminonaphthalene, 2,5-diaminonaphthalene, 2,6 diaminonaphthalene, 2,7-diaminonaphthalene, 2,8-diaminonaphthalene, 1,2-bis (4-aminophenyl) ethane, 1,2-bis (3 -Aminophenyl) ethane, 1,3-bis (4-aminophenyl) propane, 1,3-bis (3-aminophenyl) propane, 1,4-bis (4aminophenyl) butane, 1,4-bis ( 3-aminophenyl) butane, bis (3,5-diethyl-4-aminophenyl) methane, 1,4-bis (4-aminophenyl Xy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (4-aminophenyl) benzene, 1,3-bis (4-aminophenyl) benzene, 1,4-bis (4 -Aminobenzyl) benzene, 1,3-bis (4-aminophenoxy) benzene, 4,4 ′-[1,4-phenylenebis (methylene)] dianiline, 4,4 ′-[1,3-phenylenebis ( Methylene)] dianiline, 3,4 ′-[1,4-phenylenebis (methylene)] dianiline, 3,4 ′-[1,3-phenylenebis (methylene)] dianiline, 3,3 ′-[1,4 -Phenylenebis (methylene)] dianiline, 3,3 ′-[1,3-phenylenebis (methylene)] dianiline, 1,4-phenylenebis [(4-aminophenyl) methanone], 1,4-phenylenebis (3-aminophenyl) methanone], 1,3-phenylenebis [(4-aminophenyl) methanone], 1,3-phenylenebis [(3-aminophenyl) methanone], 1,4-phenylenebis (4- Aminobenzoate), 1,4-phenylenebis (3-aminobenzoate), 1,3-phenylenebis (4-aminobenzoate), 1,3-phenylenebis (3-aminobenzoate), bis (4-aminophenyl) Terephthalate, bis (3-aminophenyl) terephthalate, bis (4-aminophenyl) isophthalate, bis (3-aminophenyl) isophthalate, N, N '-(1,4-phenylene) bis (4-aminobenzamide) , N, N '-(1,3-phenylene) bis (4-aminobenzamide), N, N'-(1,4-phenyl Nylene) bis (3-aminobenzamide), N, N '-(1,3-phenylene) bis (3-aminobenzamide), N, N'-bis (4-aminophenyl) terephthalamide, N, N'- Bis (3-aminophenyl) terephthalamide, N, N'-bis (4-aminophenyl) isophthalamide, N, N'-bis (3-aminophenyl) isophthalamide, 9,10-bis (4-aminophenyl ) Anthracene, 4,4'-bis (4-aminophenoxy) diphenylsulfone, 2,2'-bis [4- (4-aminophenoxy) phenyl] propane, 2,2'-bis [4- (4-amino Phenoxy) phenyl] hexafluoropropane, 2,2'-bis (4-aminophenyl) hexafluoropropane, 2,2'-bis (3-aminophenyl) hexafluoro Propane, 2,2′-bis (3-amino-4-methylphenyl) hexafluoropropane, 2,2′-bis (4-aminophenyl) propane, 2,2′-bis (3-aminophenyl) propane, 2,2′-bis (3-amino-4-methylphenyl) propane, 3,5-diaminobenzoic acid, 2,5-diaminobenzoic acid, bis (4-aminophenoxy) methane, 1,2-bis (4 -Aminophenoxy) ethane, 1,3-bis (4-aminophenoxy) propane, 1,3-bis (3-aminophenoxy) propane, 1,4-bis (4-aminophenoxy) butane, 1,4-bis (3-aminophenoxy) butane, 1,5-bis (4-aminophenoxy) pentane, 1,5-bis (3-aminophenoxy) pentane, 1,6-bis (4-aminophenoxy) Hexane, 1,6-bis (3-aminophenoxy) hexane, 1,7-bis (4-aminophenoxy) heptane, 1,7-bis (3-aminophenoxy) heptane, 1,8-bis (4 -Aminophenoxy) octane, 1,8-bis (3-aminophenoxy) octane, 1,9-bis (4-aminophenoxy) nonane, 1,9-bis (3-aminophenoxy) nonane, 1,10-bis (4-aminophenoxy) decane, 1,10-bis (3-aminophenoxy) decane, 1,11-bis (4-aminophenoxy) undecane, 1,11-bis (3-aminophenoxy) undecane, 1,12 Aromatic diamines such as -bis (4-aminophenoxy) dodecane and 1,12-bis (3-aminophenoxy) dodecane, bis (4-aminocyclohexyl) A) alicyclic diamines such as methane and bis (4-amino-3-methylcyclohexyl) methane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane And aliphatic diamines such as 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, and 1,12-diaminododecane.

  The above-mentioned other diamines can be used alone or in combination of two or more, depending on characteristics such as liquid crystal alignment, pretilt angle, voltage holding characteristics, and accumulated charge when a liquid crystal alignment film is formed.

<Tetracarboxylic dianhydride>
In the synthesis of the polyamic acid used in the present invention, the tetracarboxylic dianhydride to be reacted with the diamine component is not particularly limited. Specific examples are given below.

  Pyromellitic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 2,3,6,7 -Anthracenetetracarboxylic acid, 1,2,5,6-anthracenetetracarboxylic acid, 3,3 ′, 4,4′-biphenyltetracarboxylic acid, 2,3,3 ′, 4′-biphenyltetracarboxylic acid, bis (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-bis (3,4-dicarboxyphenyl) propane Bis (3,4-dicarboxyphenyl) dimethylsilane, bis (3,4-dicarboxyphenyl) diphenylsilane, 2,3,4,5-pyridinetetracarboxylic acid, 2,6-bis (3,4 -Dicarboxyphenyl) pyridine, 3,3 ', 4,4'-diphenylsulfonetetracarboxylic acid, 3,4,9,10-perylenetetracarboxylic acid, 1,3-diphenyl-1,2,3,4- Cyclobutanetetracarboxylic acid, oxydiphthaltetracarboxylic acid, 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid Acid, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,2-dimethyl-1,2,3,4-cyclobutane Tetracarboxylic acid, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cycloheptanetetracarboxylic acid, 2,3,4,5-tetrahydrofurantetracarboxylic acid , 3,4-dicarboxy-1-cyclohexylsuccinic acid, 2,3,5-tricarboxycyclopentylacetic acid, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic 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 <2.6 >] Undecane- 3,5,9,11-tetracarboxylic acid, 1,2,3,4-butanetetracarboxylic acid, 4- (2,5-dioxotetrahydrofuran-3-yl) -1,2,3,4-tetra Hydrinaphthalene-1,2-dicarboxylic acid, bicyclo [2,2,2] oct-7-ene-2,3,5,6-tetracarboxylic acid, 5- (2,5-dioxotetrahydrofuryl) -3 -Methyl-3-cyclohexane-1,2-dicarboxylic acid, tetracyclo [6,2,1,1,0,2,7] dodeca-4,5,9,10-tetracarboxylic acid, 3,5 6-tricarboxynorbornane-2: 3,5: 6 dicarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid and the like.

  The tetracarboxylic dianhydride can be used alone or in combination of two or more depending on properties such as a liquid crystal alignment property, a voltage holding property, and a stored charge when a liquid crystal alignment film is formed.

<Synthesis of polyamic acid>
In order to obtain a polyamic acid by reacting a diamine component with a tetracarboxylic dianhydride, a known synthesis technique can be used. Generally, it is a method of reacting a diamine component with a tetracarboxylic dianhydride in an organic solvent. The reaction between the diamine component and the tetracarboxylic dianhydride is advantageous in that it proceeds relatively easily in an organic solvent and does not generate by-products.

  The organic solvent used in the above reaction is not particularly limited as long as the generated polyamic acid can be dissolved. Furthermore, an organic solvent that does not dissolve the polyamic acid may be used by mixing with the above solvent as long as the generated polyamic acid does not precipitate. In addition, since the water in the organic solvent inhibits the polymerization reaction and further causes the generated polyamic acid to be hydrolyzed, the organic solvent is preferably dehydrated and dried.

  Examples of the organic solvent include N, N-dimethylformamide, N, N-dimethylacetamide, N, N-diethylformamide, N-methylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, -Pyrrolidone, 1,3-dimethyl-2-imidazolidinone, 3-methoxy-N, N-dimethylpropanamide, N-methylcaprolactam, dimethylsulfoxide, tetramethylurea, pyridine, dimethylsulfone, hexamethylsulfoxide, γ- Butyrolactone, isopropyl alcohol, methoxymethylpentanol, dipentene, ethyl amyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, methyl cellosolve, ethyl cellosolve, methyl cellosolveua Tate, 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 Recall monoacetate monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3- Methoxy butyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, 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, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether acetate, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, 3 -Methyl ethyl ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, diglyme, 4-hydroxy-4-methyl- 2-pentanone, 2-ethyl-1-hexanol and the like. These organic solvents may be used alone or as a mixture.

  When reacting a diamine component and a tetracarboxylic dianhydride component in an organic solvent, a solution obtained by dispersing or dissolving the diamine component in the organic solvent is stirred, and the tetracarboxylic dianhydride component is allowed to stand as it is or the organic solvent is dissolved. Dispersing or dissolving in a solvent, adding a dicarboxylic acid to a solution obtained by dispersing or dissolving a tetracarboxylic dianhydride component in an organic solvent, and adding a diamine component to a solution obtained by dispersing or dissolving a tetracarboxylic dianhydride component in an organic solvent. A method of alternately adding them and the like are mentioned, and any of these methods may be used. When the diamine component or the tetracarboxylic dianhydride component is composed of a plurality of compounds, they may be reacted in a mixed state in advance, may be reacted individually sequentially, and may be further reacted individually in a low molecular weight. The products may be mixed and reacted to obtain a high molecular weight product.

  The temperature at which the diamine component is reacted with the tetracarboxylic dianhydride component can be selected at any temperature, and is, for example, in the range of -20 to 150C, preferably -5 to 100C. The reaction can be performed at any concentration, for example, 1 to 50% by mass, preferably 5 to 30% by mass.

  In the above polymerization reaction, the ratio of the total number of moles of the tetracarboxylic dianhydride component to the total number of moles of the diamine component can be selected arbitrarily according to the molecular weight of the polyamic acid to be obtained. As in the ordinary polycondensation reaction, the molecular weight of the generated polyamic acid increases as the molar ratio approaches 1.0. A preferred range is 0.8 to 1.2.

  The method for synthesizing the polyamic acid used in the present invention is not limited to the above-described method, and, like the general method for synthesizing a polyamic acid, replacing the tetracarboxylic dianhydride with a tetracarboxylic acid having a corresponding structure. The corresponding polyamic acid can also be obtained by reacting with a known method using a carboxylic acid or a tetracarboxylic acid derivative such as tetracarboxylic dihalide.

Examples of the method of imidizing the polyamic acid to obtain a polyimide include a thermal imidization in which a solution of the polyamic acid is directly heated and a catalyst imidization in which a catalyst is added to the solution of the polyamic acid.
In the polyimide used in the present invention, the imidation ratio from the polyamic acid to the polyimide does not necessarily need to be 100%.

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

  Catalytic imidation of the polyimide precursor can be carried out by adding a basic catalyst and an acid anhydride to the solution of the polyimide precursor and stirring at -20 to 250C, preferably 0 to 180C. The amount of the basic catalyst is 0.5 to 30 times, preferably 2 to 20 times, the number of the amide acid groups, and the amount of the acid anhydride is 1 to 50 times, preferably 3 to the mole of the amide acid groups. It is 30 mole times. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, trioctylamine, and the like. Among them, pyridine is preferable because it has an appropriate basicity for causing the reaction to proceed. Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, and pyromellitic anhydride. Among them, acetic anhydride is preferred because purification after the reaction is facilitated. The imidization rate by the catalytic imidization can be controlled by adjusting the amount of the catalyst, the reaction temperature, the reaction time, and the like.

  When recovering the produced polyimide precursor or polyimide from the polyimide precursor or polyimide reaction solution, the reaction solution may be put into a poor solvent to precipitate. Examples of the poor solvent used for precipitation include methanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, and water. The polymer that has been put into a poor solvent and precipitated is collected by filtration and then dried at normal temperature or under reduced pressure at normal temperature or under heating. Further, by repeating the operation of re-dissolving the polymer recovered by precipitation in an organic solvent and recovering and recovering the precipitate 2 to 10 times, impurities in the polymer can be reduced. Examples of the poor solvent at this time include alcohols, ketones, and hydrocarbons. It is preferable to use three or more kinds of poor solvents selected from these, because the purification efficiency is further increased.

<Liquid crystal aligning agent>
The liquid crystal aligning agent of the present invention contains the polymerizable compound represented by the formula (1) and at least one polymer selected from the group consisting of the polyimide precursor and the polyimide. In addition to these components, other polymer components for forming a resin film may be contained. The content of all resin components is 1 to 20% by mass, preferably 3 to 15% by mass, more preferably 3 to 10% by mass, based on 100% by mass of the liquid crystal aligning agent.

The resin component in the liquid crystal alignment agent of the present invention may be all at least one polymer selected from the group consisting of a polyimide precursor having a side chain A and / or a side chain B and a polyimide. May be mixed, and further, other polymers may be mixed. At that time, the content of the other polymer in the resin component is preferably 0.5 to 15% by mass, and more preferably 1 to 10% by mass.
Examples of other polymers include, for example, a polyimide precursor or polyimide having no side chain B, and a polyimide precursor or polyimide having neither the side chain A nor the side chain B. Not limited.

The molecular weight of the polymer of the above resin component is determined by the weight average measured by the GPC (Gel Permeation Chromatography) method in consideration of the strength of the obtained coating film, workability in forming the coating film, and uniformity of the coating film. The molecular weight (Mw) is preferably from 5,000 to 1,000,000, and more preferably from 10,000 to 150,000.
The content of the polymerizable compound represented by the formula (1) in the liquid crystal aligning agent of the present invention is 3 to 30 parts by mass, preferably 5 to 20 parts by mass, more preferably 5 to 30 parts by mass with respect to 100 parts by mass of the resin component. １５15 parts by mass. In the case of such a content, the effects of the present invention can be obtained.

<Solvent>
The organic solvent used for the liquid crystal aligning agent of the present invention is not particularly limited as long as the organic solvent dissolves the above-mentioned resin component. The organic solvent may be a single solvent or a mixed solvent of two or more. Specific examples of the organic solvent include the organic solvents exemplified in the above polyamic acid synthesis. Among them, N-methyl-2-pyrrolidone, γ-butyrolactone, N-ethyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, or 3-methoxy-N, N-dimethylpropanamide is a resin component. Is preferred from the viewpoint of solubility.
Further, a solvent as described below has an effect of improving the uniformity and smoothness of the coating film, and is preferably used by mixing with a solvent having high solubility of the resin component.
For example, isopropyl alcohol, methoxymethylpentanol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl cellosolve acetate, butyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol, ethyl carbitol acetate, 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, diethylene glycol, diethylene glycol Cole 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-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate , Butyl butyrate Butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, n-hexane, n-pentane, n-octane, diethyl ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene acetate Glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, 3-methoxy Propyl propionate, butyl 3-methoxypropionate, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanol, propylene glyco Monoacetate, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2- (2-ethoxypropoxy) propanol, methyl lactate Examples include esters, ethyl lactate, n-propyl lactate, n-butyl lactate, isoamyl lactate, and 2-ethyl-1-hexanol. These solvents may be used in combination of two or more. When these solvents are used, the content is preferably 5 to 80% by mass, more preferably 20 to 60% by 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. For example, a compound that improves the film thickness uniformity and surface smoothness when a liquid crystal alignment agent is applied, a compound that improves the adhesion between the liquid crystal alignment film and the substrate, and the like are given.

  Examples of the compound that improves the uniformity of the film thickness and the surface smoothness include a fluorine-based surfactant, a silicone-based surfactant, and a nonionic surfactant. More specifically, for example, F-top EF301, EF303, EF352 (manufactured by Tochem Products), Megafac F171, F173, R-30 (manufactured by Dainippon Ink), Florado FC430, FC431 (manufactured by Sumitomo 3M) ), Asahigard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by Asahi Glass Co., Ltd.). When these surfactants are used, the use ratio thereof is preferably 0.01 to 2 parts by mass, more preferably 0.01 to 1 part by mass, per 100 parts by mass of the resin component contained in the liquid crystal aligning agent. Parts by weight.

Specific examples of the compound that improves the adhesion between the liquid crystal alignment film 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-aminopropyltrimethoxysilane N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxy Carbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-tri Toxisilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxy Silane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis (oxyethylene) -3-aminopropyl Trimethoxysilane, N-bis (oxyethylene) -3-aminopropyltriethoxysilane, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, poly Propylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl ether -2,4-hexanediol, N, N, N ', N',-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N ' , N ',-Tetraglycidyl-4,4'-diaminodiphenylmethane, 3- (N-allyl-N-glycidyl) aminopropyltrimethoxysilane, 3- (N, N-diglycidyl) aminopropyltrimethoxysilane and the like. Can be
Further, in order to further increase the rubbing resistance of the coating film obtained from the liquid crystal alignment agent, phenol compounds such as 2,2'-bis (4-hydroxy-3,5-dihydroxymethylphenyl) propane and tetra (methoxymethyl) bisphenol are used. May be added. When these compounds are used, the amount is preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, per 100 parts by mass of the resin component contained in the liquid crystal aligning agent.
In the liquid crystal alignment agent of the present invention, in addition to the above, as long as the effects of the present invention are not impaired, a dielectric or a conductive substance for the purpose of changing the electrical characteristics such as the dielectric constant or conductivity of the liquid crystal alignment film may be used. It may be added.

<Liquid crystal alignment film>
A cured film obtained by applying the liquid crystal aligning agent of the present invention to a substrate, followed by drying and baking, if necessary, can be used as a liquid crystal aligning film as it is. The cured film is subjected to rubbing, irradiation of polarized light or light of a specific wavelength, treatment of an ion beam, or the like, and application of a voltage to a liquid crystal display element after liquid crystal filling as an alignment film for SC-PVA. It is also possible to irradiate UV with the voltage applied.

  The substrate is not particularly limited as long as it is a substrate having a high transparency, and a glass plate, polycarbonate, poly (meth) acrylate, polyethersulfone, polyarylate, polyurethane, polysulfone, polyether, polyetherketone, trimethylpentene, Polyolefin, polyethylene terephthalate, (meth) acrylonitrile, triacetyl cellulose, diacetyl cellulose, acetate butyrate cellulose, and the like can be used. In addition, it is preferable to use a substrate on which an ITO (Indium Tin Oxide) electrode for driving a liquid crystal is formed, from the viewpoint of simplifying the process. In the case of a reflection type liquid crystal display element, an opaque object such as a silicon wafer can be used as long as only one substrate is used. In this case, a material which reflects light such as aluminum can be used.

  The method for applying the liquid crystal aligning agent is not particularly limited, and examples thereof include printing methods such as screen printing, offset printing, and flexographic printing, inkjet methods, spray methods, roll coating methods, dips, roll coaters, slit coaters, and spinners. From the viewpoint of productivity, the transfer printing method is widely used industrially, and is suitably used in the present invention.

  A coating film formed by applying a liquid crystal aligning agent by the above method can be fired to form a cured film. The drying step after applying the liquid crystal aligning agent is not necessarily required, but when the time from application to baking is not constant for each substrate, or when baking is not performed immediately after application, a drying step is performed. Is preferred. This drying may be performed as long as the solvent is removed to such an extent that the shape of the coating film is not deformed by the transfer of the substrate or the like, and the drying means is not particularly limited. For example, a method of drying on a hot plate at a temperature of 40 to 150 ° C., preferably 60 to 100 ° C. for 0.5 to 30 minutes, preferably 1 to 5 minutes can be mentioned.

  The sintering temperature of the coating film formed by applying the liquid crystal alignment agent is not limited, and may be, for example, an arbitrary temperature of 100 to 350 ° C, preferably 120 to 300 ° C, more preferably 150-250 ° C. The firing can be performed for an arbitrary time of 5 to 240 minutes. Preferably it is 10 to 90 minutes, more preferably 20 to 90 minutes. Heating can be performed by a known method, for example, a hot plate, a hot air circulation furnace, an infrared furnace, or the like.

  The thickness of the liquid crystal alignment film obtained by firing is not particularly limited, but is preferably 5 to 300 nm, more preferably 10 to 120 nm.

<Liquid crystal display device>
The liquid crystal display element of the present invention can be obtained by forming a liquid crystal alignment film on a substrate by the above method, and then manufacturing a liquid crystal cell by a known method.
As a specific example of the liquid crystal display element, two substrates disposed so as to face each other, a liquid crystal layer provided between the substrates, and provided between the substrate and the liquid crystal layer, the liquid crystal alignment agent of the present invention This is a vertical alignment type liquid crystal display device including a liquid crystal cell having the formed liquid crystal alignment film. Specifically, the liquid crystal alignment agent of the present invention is applied to two substrates and baked to form a liquid crystal alignment film, and the two substrates are arranged so that the liquid crystal alignment films face each other. A liquid crystal layer composed of liquid crystal is sandwiched between two substrates, a liquid crystal layer is provided in contact with a liquid crystal alignment film, and ultraviolet rays are applied while applying a voltage to the liquid crystal alignment film and the liquid crystal layer. This is a vertical alignment type liquid crystal display device having a liquid crystal cell to be manufactured.
Using the liquid crystal alignment film formed by the liquid crystal alignment agent of the present invention, while applying a voltage to the liquid crystal alignment film and the liquid crystal layer, irradiating ultraviolet rays to polymerize the polymerizable compound and the photoreactivity of the polymer By reacting the side chain with each other or the photoreactive side chain of the polymer with the polymerizable compound, the orientation of the liquid crystal is more efficiently fixed, and the liquid crystal display device has a remarkably excellent response speed.

The substrate used for the liquid crystal display device of the present invention is not particularly 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. As a specific example, the same substrate as the substrate described for the liquid crystal alignment film can be used.
The liquid crystal display element of the present invention may use a substrate provided with a conventional electrode pattern or projection pattern, but by having a liquid crystal alignment film formed using the liquid crystal alignment agent of the present invention, It is possible to operate even if a line / slit electrode pattern of, for example, 1 to 10 μm is formed on one side substrate, and a substrate having a structure in which a slit pattern or a projection pattern is not formed as an opposite substrate is used. The process at the time can be simplified, and a high transmittance can be obtained.

In the case of a high-performance element such as a TFT element, an element such as a transistor formed between an electrode for driving liquid crystal and a substrate is used.
In the case of a transmissive liquid crystal display device, the above substrate is generally used, but in the case of a reflective liquid crystal display device, an opaque substrate such as a silicon wafer can be used if only one substrate is used. It is. At that time, a material such as aluminum which reflects light can be used for the electrode formed on the substrate.

  The liquid crystal alignment film is formed by applying the liquid crystal alignment agent of the present invention on this substrate and then baking the same, and as described above in detail.

  The liquid crystal material constituting the liquid crystal layer of the liquid crystal display device of the present invention is not particularly limited, and a liquid crystal material used in a conventional vertical alignment system, for example, a negative type liquid crystal such as MLC-6608 and MLC-6609 manufactured by Merck & Co., Ltd. Liquid crystals can be used.

  To produce the liquid crystal display device of the present invention, the polymerizable compound of the present invention may be contained in at least one of the liquid crystal alignment agent and the liquid crystal layer.

As a method of sandwiching the liquid crystal layer between two substrates, a known method can be used. For example, a pair of substrates on which a liquid crystal alignment film is formed is prepared, and spacers such as beads are scattered on the liquid crystal alignment film of one of the substrates so that the surface on which the liquid crystal alignment film is formed is inward. Then, the other substrate is bonded, and a liquid crystal is injected under reduced pressure and sealed.
In addition, a pair of substrates on which a liquid crystal alignment film is formed is prepared, a spacer such as beads is sprayed on the liquid crystal alignment film of one substrate, and then liquid crystal is dropped. The liquid crystal cell can also be manufactured by a method in which the other substrate is bonded and sealed so that the surface of the liquid crystal panel faces inside. At this time, the thickness of the spacer is preferably 1 to 30 μm, more preferably 2 to 10 μm.

The step of manufacturing a liquid crystal cell by irradiating ultraviolet rays while applying a voltage to the liquid crystal alignment film and the liquid crystal layer includes, for example, applying a voltage between electrodes provided on a substrate to thereby apply the voltage to the liquid crystal alignment film and the liquid crystal layer. And applying an ultraviolet ray 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 dose of ultraviolet rays, for example, 1~60J / cm ^2, preferably at 40 J / cm ² or less, more preferably 20 J / cm ² or less. It is preferable that the amount of ultraviolet light irradiation is small, because the reliability can be prevented from deteriorating due to the destruction of the liquid crystal and members constituting the liquid crystal display element, and the irradiation time of ultraviolet light can be reduced, thereby increasing the production efficiency.
The wavelength of the ultraviolet light used is preferably 300 to 400 nm, more preferably 310 to 370 nm.

When ultraviolet rays are applied to the liquid crystal alignment film and the liquid crystal layer while applying a voltage, the polymerizable compound reacts to form a polymer, and the polymer stores the tilting direction of the liquid crystal molecules, thereby obtaining a liquid crystal display. The response speed of the element can be increased.
Further, when ultraviolet rays are applied to the liquid crystal alignment film and the liquid crystal layer while applying a voltage, at least one selected from the group consisting of a polyimide precursor having a reactive side chain, and a polyimide obtained by imidizing the polyimide precursor. Since the photoreactive side chains of the two polymers or the photoreactive side chains of the polymers react with the polymerizable compound, the response speed of the obtained liquid crystal display device can be increased.

  Further, the liquid crystal aligning agent of the present invention is useful not only as a liquid crystal aligning agent for producing a liquid crystal display device of a vertical alignment type such as a PSA type liquid crystal display or an SC-PVA type liquid crystal display, but also rubbing treatment and optical alignment. It can also be suitably used for producing a liquid crystal alignment film formed by the treatment.

  Hereinafter, the present invention will be described more specifically with reference to Examples, but the present invention is not limited thereto. The abbreviations of the compounds in the following are as follows.

BODA: bicyclo [3,3,0] octane-2,4,6,8-tetracarboxylic dianhydride.
CBDA: 1,2,3,4-cyclobutanetetracarboxylic dianhydride.
PMDA: pyromellitic anhydride.
TCA: 2,3,5-tricarboxycyclopentylacetic acid-1,4,2,3-dianhydride.

DBA: 3,5-diaminobenzoic acid

NMP: N-methyl-2-pyrrolidone.
BCS: butyl cellosolve.
3AMP: 3-picolylamine.

<Synthesis example 1>

<Synthesis of RM1-A>
At room temperature, 20 g (93.4 mmol) of 4- (4-hydroxyphenyl) benzoic acid, 70.0 g (3.5 wt) of NMP, and 38.7 g of potassium carbonate were placed in a 500 mL (milliliter) four-necked flask equipped with a magnetic stirrer. (3.0 eq) and 0.776 g (5.0 mol%) of potassium iodide were charged, and 10.0 g (0.5 wt) of NMP was added to the reaction solution while washing the wall of the flask, followed by stirring. Thereafter, the temperature was raised to 100 ° C., and 35.7 g (2.5 eq) of 4-chlorobutyraldehyde dimethyl acetal and 10.0 g (0.5 wt) of NMP were reacted while washing the powder attached to the wall of the flask. The mixture was poured into the system, stirred for 18 hours, and reacted.
After the reaction, 120 g (6.0 wt) of toluene was added and the mixture was filtered, and the residue was washed twice with 20.0 g (1 wt) of toluene. Next, the combined toluene filtrate was washed three times with 80.0 g (4 wt) of water. Thereafter, the resultant was dried in a vacuum at 50 ° C. to distill off the solvent. Ethyl acetate (30.0 g, 1.5 wt) was added to the residue, and the mixture was heated to 50 ° C. and dissolved. Thereafter, 140 g (7 wt) of heptane was added dropwise and cooled to 0 ° C. A small amount of a seed crystal was added to precipitate a crystal. The crystals were filtered, washed twice with 20.0 g (1 wt) of heptane, and dried in vacuo at 30 ° C. to obtain 38.0 g of RM1-A (yield: 91%, property: white solid).

<Synthesis of RM1>
At room temperature, 35.0 g (78.4 mmol) of RM1-A and 105 g (3.0 wt) of THF were charged into a 1-L four-necked flask equipped with a magnetic stirrer, and stirred to confirm that they had been dissolved. 38.9 g (2.2 eq) of tin dihydrate and 33.4 g (2.2 eq) of ethyl 2- (bromomethyl) acrylate were sequentially charged, and the temperature was raised to 60 ° C. Subsequently, 125 g (3.6 wt) of 0.1 M hydrochloric acid was dropped, and 245 g (7 wt) of THF was poured into the reaction system while washing the powder attached to the wall of the flask, and the mixture was stirred for 14.5 hours. Reacted.
The reaction solution was cooled to 50 ° C., and 350 g (10 wt) of toluene was added thereto for liquid separation to remove a hydrochloric acid layer. Thereafter, the organic layer was added dropwise to 263 g (7.5 wt) of a 12.9% by mass aqueous solution of potassium hydroxide at 50 ° C. over 30 minutes, and after stirring, the organic layer was separated. 262 g (7.5 wt) of a 5.2 mass% aqueous solution of potassium hydroxide was added to the obtained organic layer, and the mixture was stirred. 3.49 g (10 wt%) of activated carbon was added to the separated organic layer, and the mixture was stirred at 50 ° C for 30 minutes, and then filtered at 50 ° C. The filtrate was washed twice with 17.5 g (0.5 wt) of toluene, and the combined filtrate of the toluene was cooled to 5 ° C. while stirring and aged for 1 hour. The precipitated solid was filtered, and the residue was washed twice with 17.5 g (0.5 wt) of heptane. The residue was vacuum dried at 40 ° C. to obtain 19.7 g of RM1 (yield: 51%, property: white crystal).
¹ H-NMR (400 MHz) in DMSO-d6: 1.79-1.87 ppm (m, 8H), 2.64 ppm (dd, J = 7.4, 18.6 Hz, 2H), 3.10 ppm (dd, J = 8.4. 14.0 Hz, 2H ), 4.08 ppm (t, J = 5.6 Hz, 2H), 4.31 ppm (t, J = 6.8 Hz, 2H), 4.61-4.68 ppm (m, 2H), 5.73 ppm (s, 2H), 6.04 ppm (d , J = 4.8 Hz, 2H), 7.06 ppm (d, J = 8.8 Hz, 2H), 7.70 ppm (d, J = 4.4 Hz, 2H), 7.78 ppm (d, J = 4.4 Hz, 2H), 8.01 ppm (d, J = 8.4 Hz, 2H).

<Synthesis Example 2>

<Synthesis of RM2-A>
At room temperature, 80.0 g (430 mmol) of 4,4′-biphenol and 160.0 g (2.0 wt) of DMF were charged into a 500 mL four-necked flask equipped with a magnetic stirrer, and dissolved by stirring. Thereafter, 77.2 g (1.3 eq) of potassium carbonate and 3.57 g (5.0 mol%) of potassium iodide were sequentially added. Thereafter, the temperature was raised to 80 ° C., 65.6 g (1.0 eq) of 4-chlorobutyraldehyde dimethyl acetal was added dropwise over 1 hour, and the mixture was stirred and reacted for 19.5 hours.
After the reaction solution was dropped into 1600 g (20 wt) of water, the mixture was stirred for 0.5 hour, and the precipitated solid was filtered. The residue was washed twice with 40.0 g (0.5 wt) of water. Thereafter, the residue was dried under reduced pressure at 40 ° C. for 1.5 hours. 880 g (11 wt) of methanol was added to the dried residue, and the crystals were washed by stirring in a suspended state (hereinafter, referred to as slurry washing) and then filtered. The residue was washed twice with 8.00 g (0.1 wt) of methanol. The solvent of the combined filtrate such as methanol was distilled off under reduced pressure to obtain a residue. The obtained residue was slurry-washed with 1040 g (13 wt) of chloroform and filtered. The filtrate was washed twice with 16.0 g (0.2 wt) of chloroform, and the solvent of the combined chloroform filtrate was distilled off. To the obtained residue, 104 g (1.3 wt) of THF and 326 g (4.1 wt) of heptane were added, and the mixture was cooled to 0 ° C. for crystallization. 400 g (5 wt) of methanol was added to the precipitated solid, the slurry was washed, and filtered. The residue was dried under reduced pressure at 40 ° C. to obtain 33.6 g of RM2-A (yield: 26%, property: white solid).

<Synthesis of RM2-B>
At room temperature, into a 500 mL four-necked flask equipped with a magnetic stirrer, 33.6 g (111 mmol) of RM2-A and 169 g (5 wt) of DMF were charged and dissolved by stirring, and 20.0 g (1.3 eq) of potassium carbonate was dissolved. Was added. Thereafter, the temperature was raised to 80 ° C., 25.6 g (1.3 eq) of 2- (4-bromobutyl) -1,3-dioxolan was added dropwise, and the mixture was stirred and reacted for 24.5 hours.
After the reaction solution was added dropwise to 672 g (20 wt) of water, the mixture was stirred for 0.5 hour, and the precipitated solid was filtered. The residue was washed twice with 16.8 g (0.5 wt) of water. Then, the residue was vacuum-dried at 40 ° C. for 1.5 hours. 100 g (3.0 wt) of toluene was added to the dried cake, and the mixture was heated to 70 ° C. and dissolved. Thereafter, 198 g (6.0 wt) of heptane was added dropwise, cooled to 0 ° C, and the precipitated solid was filtered. The obtained residue was washed twice with 10.0 g (0.3 wt) of heptane. The residue was vacuum dried at 40 ° C. to obtain 35.6 g of RM2-B (yield: 75%, property: white solid).

<Synthesis of RM2>
At room temperature, in a 1 L four-necked flask equipped with a magnetic stirrer, 50.0 g (116 mmol) of RM2-B and 500 g (10 wt) of THF were charged, and after stirring to confirm dissolution, tin chloride dihydrate was used. 57.7 g (2.2 eq) of the product and 49.3 g (2.2 eq) of ethyl 2- (bromomethyl) acrylate were sequentially charged, and the temperature was raised to 60 ° C. Thereafter, 179 g (3.6 wt) of 0.1 M hydrochloric acid was added dropwise, and the mixture was stirred and reacted for 26 hours.
The reaction solution was cooled to 50 ° C., 500 g (10 wt) of toluene was added, and the mixture was separated to remove a hydrochloric acid layer. The organic layer was added dropwise to 375 g (7.5 wt) of a 12.9% by mass aqueous solution of potassium hydroxide at 50 ° C. over 30 minutes, and then the organic layer was separated. 375 g (7.5 wt) of a 5.2 mass% aqueous potassium hydroxide solution was added to the organic layer, and the mixture was separated at 50 ° C. The separated organic layer was washed with 375 g (7.5 wt) of water. 5.12 g (10 wt%) of activated carbon was added to the washed organic layer, and the mixture was stirred at 50 ° C for 30 minutes, and then filtered at 50 ° C. The filtrate was washed twice with 25.0 g (0.5 wt) of toluene, and the combined filtrate of toluene was cooled to 5 ° C. with stirring and aged for 1 hour. The precipitated solid was filtered, and the residue was washed twice with 25.0 g (0.5 wt) of heptane. The residue was vacuum dried at 40 ° C. to obtain 35.6 g of RM2 (yield: 83%, property: white crystal).
¹ H-NMR (400 MHz) in DMSO-d6: 1.42-1.58 ppm (m, 2H), 1.62-1.86 ppm (m, 8H), 2.58-2.67 ppm (m, 2H), 3.06-3.11 ppm (m, 2H ), 4.00-4.03 ppm (m, 4H), 4.55-4.66 ppm (m, 2H), 5.71 ppm (s, 1H), 5.73 ppm (s, 1H), 6.03 ppm (s, 1H), 6.05 ppm (s , 1H), 6.98 ppm (d, J = 8.8 Hz, 4H), 7.52 ppm (d, J = 8.8 Hz, 4H).

<Synthesis Example 3>

<Synthesis of RM3-A>
At room temperature, 50.0 g (269 mmol) of 4,4′-biphenol and 175 g of DMF were charged into a 500 mL four-necked flask equipped with a magnetic stirrer, stirred and dissolved, and then 48.24 g (1.3 eq) of potassium carbonate. ) Was added. Thereafter, the temperature was raised to 80 ° C., and 48.61 g (1.0 eq) of 2- (2-bromoethyl) -1,3-dioxolan was added dropwise over 1 hour, and the mixture was stirred and reacted for 7 hours. Next, the reaction solution was added dropwise to 1000 g of water, and the mixture was stirred at room temperature for 0.5 hour, and the precipitated solid was filtered. 550 g of methanol was added to the residue, the slurry was washed at room temperature, and then filtered at 0 to 5 ° C. 650 g of chloroform was added to the residue obtained by distilling off the solvent of the filtrate, and the mixture was washed with slurry at room temperature and then filtered. To the residue from which the solvent of the filtrate was distilled off, 15 g of THF was added and dissolved, 37.5 g of toluene was added, and the mixture was stirred in an ice bath for 0.5 hour. The precipitated crystals were collected by filtration, washed (12.5 g of toluene), and dried at 40 ° C. under reduced pressure to obtain 9.0 g of RM3-A (yield: 12%, properties: gray crystals).

<Synthesis of RM3-B>
At room temperature, into a 500 mL four-necked flask equipped with a magnetic stirrer, 8.31 g (29 mmol) of RM3-A and 12.5 g of NMP were charged, stirred and dissolved, and then 6.01 g (1.5 eq.) Of potassium carbonate. ) Was added. Thereafter, the temperature was raised to 80 ° C., and 5.79 g (1.1 eq) of 2- (4-bromobutyl) -1,3-dioxolan was added dropwise over 10 minutes, and the mixture was stirred and reacted for 19 hours. Next, 83 g of ethyl acetate was added to the reaction solution, and the precipitated inorganic salt was filtered. Thereafter, the filtrate was separated and washed three times with 24 g of water, and the solvent of the filtrate was distilled off. After adding 24 g of toluene to the obtained residue and dissolving it at 70 ° C., 48 g of heptane was added and stirred for a while in an ice bath. The precipitated crystals were filtered and dried at 40 ° C. under reduced pressure to obtain 12.2 g of RM3-B (yield: 91%, property: white solid).

<Synthesis of RM3>
At room temperature, 11.0 g (26.5 mmol) of RM3-B and 110 g of THF were charged into a 500 mL four-necked flask equipped with a magnetic stirrer, stirred and dissolved, and then 14.4 g of tin chloride dihydrate ( 2.4 eq) and 49.3 g (2.2 eq) of ethyl 2- (bromomethyl) acrylate. Thereafter, 38.5 g of 10% by mass hydrochloric acid was added dropwise and reacted for 120 hours. The reaction solution was concentrated under reduced pressure to about one-third, cooled to 15 ° C., and the precipitated crystals were filtered and washed (44 g of water × 3 times). Then, the crystals were dissolved in 165 g of THF, and diluted with 110 g of toluene. The resulting solution was added dropwise to 82.5 g of a 12.9% by mass aqueous potassium hydroxide solution at room temperature, and the aqueous layer was separated and removed. To the obtained organic layer, 82.5 g of a 5.2 mass% aqueous potassium hydroxide solution was added at room temperature, and the aqueous layer was separated and removed. Thereafter, the organic layer was washed 5 times with 82.5 g of water, 0.55 g (5% by mass) of specially made Shirasagi activated carbon was added, and the mixture was stirred at room temperature for 1 hour and filtered. Thereafter, the filtrate was concentrated under reduced pressure to about 15 g, and stirred at 5 ° C. for a while. The precipitated crystals were filtered, washed (5.5 g of heptane × 2 times), and dried under reduced pressure at 40 ° C. to obtain 7.1 g of RM3 (yield: 53%, properties: white crystals).
¹ H-NMR (400 MHz) in DMSO-d6: 1.40-1.82 ppm (m, 6H), 2.08-2.13 ppm (m, 2H), 2.55-2.81 ppm (m, 2H), 3.06-3.11 ppm (m, 2H ), 3.98-4.18 ppm (m, 4H), 4.55-4.85 ppm (m, 2H), 5.72 ppm (d, J = 8.8 Hz, 2H), 6.05 ppm (d, J = 8.8 Hz, 2H), 6.97- 7.08 ppm (m, 4H), 7.52-7.61 ppm (m, 4H).

<Synthesis example 4>
RM4 was synthesized by the method disclosed in WO2012 / 002513.
<Synthesis example 5>
RM5 was synthesized by the method disclosed in Japanese Patent Application No. 2014-015830.

<Synthesis example 6>

<Synthesis of RM6-A>
At room temperature, in a 1 L four-necked flask equipped with a magnetic stirrer, 55.8 g (300 mmol) of 4,4′-biphenol, 62.7 g (1.0 eq) of 2- (4-bromobutyl) -1,3-dioxolan, And 234 g (4.2 wt) of acetone were successively charged, and 53.9 g (1.3 eq) of potassium carbonate was further added with stirring. Then, 156 g (2.8 wt) of acetone was added to the powder adhering to the wall of the flask. It was poured into the reaction system while washing. Thereafter, the temperature was raised to 60 ° C., and the mixture was stirred and reacted for 41.5 hours.
Then, after allowing to cool to room temperature, the reaction solution was added dropwise to 3013 g (54 wt) of water and stirred for 30 minutes. Next, the precipitated solid was filtered and the residue was dried at 30 ° C. under reduced pressure. 614 g (11 wt) of methanol was added to the dried solid, and the mixture was stirred to wash the slurry. Thereafter, the mixture was filtered, and the obtained filtrate was concentrated. To the obtained residue, 725 g (13 wt) of chloroform was added, and the mixture was stirred to wash the slurry. Next, the obtained filtrate was concentrated under reduced pressure. To the obtained residue, 72.5 g (1.3 wt) of THF was added, and 273 g (4.9 wt) of heptane was added dropwise, and the mixture was cooled to 0 ° C. The precipitated solid was filtered, washed with heptane, and dried under reduced pressure to obtain 31.6 g of RM6-A (yield: 34%, property: white solid).

<Synthesis of RM6-B>
At room temperature, in a 500 mL four-necked flask equipped with a magnetic stirrer, 19.7 g (62.6 mmol) of RM6-A, 43.1 g (5.0 eq) of potassium carbonate, 1.04 g (10 mol%) of potassium iodide, and 148 g (7.5 wt) of DMF were sequentially charged, stirred, and heated to 100 ° C. Further, 4.80 g (1.8 eq) of 4-chloro-1-butanol was added dropwise, and the mixture was stirred and reacted for 27 hours. During the course of the reaction, the reaction slowed down, and 2.40 g (0.3 eq) of 4-chloro-1-butanol was added twice.
Thereafter, the reaction solution was filtered, and potassium carbonate was separated by filtration. The filtrate was concentrated to 4.3 wt, and the residue was dropped into 400 g (20 wt) of water to precipitate crystals. 197 g (10 wt) of THF was added to the obtained crystals, dissolved at 40 ° C., and 197 g (10 wt) of heptane was added dropwise to precipitate crystals. Thereafter, the solution containing the crystals was cooled to 0 ° C., and filtered, and the obtained crystals were dried under reduced pressure to obtain 19.4 g of RM6-B (yield: 80%, property: pale brown solid).

<Synthesis of RM6-C>
At room temperature, 155 g (8.0 wt) of THF was added to 19.4 g (50.3 mmol) of RM6-B, and after dissolution was confirmed with stirring, 55.4 mg (0.5 mol%) of BHT and tin chloride 2 were added. 20.4 g (1.8 eq) of a hydrate and 17.5 g (1.8 eq) of ethyl 2- (bromomethyl) acrylate were sequentially charged. Thereafter, the temperature was raised to 60 ° C., 69.4 g (3.6 wt) of 0.1 M hydrochloric acid was added dropwise, and the mixture was stirred and reacted for 18 hours.
Next, after adjusting the temperature to 50 ° C., 194 g (10 wt) of toluene was added, and liquid separation was performed. The organic layer was added dropwise to 150 g (7.5 wt) of a 12.9% by mass aqueous solution of potassium hydroxide at 50 ° C. over 30 minutes, but insolubles were precipitated. Therefore, 637 g (32.8 wt) of a 12.9% by mass aqueous solution of potassium hydroxide was added to dissolve insolubles, and then the mixture was separated at 50 ° C. Next, the separated organic layer was washed with 150 g (7.5 wt) of a 5.2 mass% aqueous solution of potassium hydroxide and further with 150 g (7.5 wt) of water. To the washed organic layer, 2.00 g of activated carbon (special Shirasagi, 10 wt%) was added, and the mixture was stirred at 50 ° C. for 30 minutes and filtered while hot. The filtrate was washed twice with 10.5 g (0.5 wt) of toluene, and the combined filtrate was aged at 5 ° C for 30 minutes. Thereafter, the precipitated solid was filtered and washed twice with 10.5 g (0.5 wt) of heptane. The obtained solid was dried under reduced pressure at 40 ° C. to obtain 3.2 g of RM6-C (yield: 16%, property: white solid).

<Synthesis of RM6>
At room temperature, into a 500 mL four-necked flask equipped with a magnetic stirrer, 3.1 g (7.5 mmol) of RM6-C was charged, and 308 g (100 wt) of THF was added and dissolved while stirring. Thereafter, 10.3 g (13.6 eq.) Of triethylamine and 10.2 g (13 eq) of methacrylic chloride were added dropwise over 1 hour, and the mixture was stirred and reacted for 19.5 hours.
Next, 217 g (70 wt) of water was added to dissolve triethylamine hydrochloride, and 208 g (67 wt) of toluene was further added to carry out liquid separation. The separated organic layer was washed twice with 151 g (49 wt) of water. Thereafter, in order to avoid the occurrence of a polymerization reaction, the solvent was distilled off under reduced pressure at 25 ° C. until the amount of the solvent became 10 g (3.3 wt). After 40.3 g (13 wt) of heptane was added dropwise to the obtained residue, the mixture was cooled to 0 ° C and aged for 1 hour. The precipitated solid was filtered and washed twice with 9.3 g (3.0 wt) of heptane. The obtained solid was dried under vacuum at 25 ° C. to obtain 2.4 g of RM6 (yield: 67%, property: white crystal).
¹ H-NMR (400 MHz) in DMSO-d6: 1.42-1.84 ppm (m, 10H), 1.88 ppm (s, 3H), 2.60 ppm (dd, J = 6.0, 17.2 Hz, 1H), 3.10 ppm (dd, J = 8.0, 17.2 Hz, 1H), 3.99-4.00 ppm (m, 4H), 4.17 ppm (t, J = 6.0 Hz, 2H), 4.59 ppm (quint, J = 6.0 Hz, 1H), 5.69 ppm (d , J = 16.4 Hz, 2H), 6.03 ppm (s, 2H), 6.97 ppm (d, J = 6.0 Hz, 4H), 7.51 ppm (d, J = 8.0 Hz, 4H).

The hydrogen nuclear magnetic resonance in Synthesis Example ⁽¹ HNMR) are, NMR instrument (JEOL Datum Ltd., JNW-ECA500) using a deuterated dimethyl sulfoxide (DMSO-d6) measured in a solvent, chemical The shift was indicated by a δ value (ppm) when tetramethylsilane was used as an internal standard.

<Polyimide molecular weight measurement>
Apparatus: Room temperature gel permeation chromatography (GPC) apparatus (SSC-7200) manufactured by Senshu Kagaku Co., Ltd.
Columns: Shodex columns (KD-803, KD-805),
Column temperature: 50 ° C,
Eluent: N, N′-dimethylformamide (as an additive, lithium bromide hydrate (LiBr · H ₂ O) 30 mmol / L, phosphoric acid / anhydrous crystal (o-phosphoric acid) 30 mmol / L, Tetrahydrofuran (THF) at 10 ml / L),
Flow rate: 1.0 ml / min,
Standard samples for preparing a calibration curve: TSK standard polyethylene oxide (molecular weight of about 9,000,000, 150,000, 100,000, and 30,000) manufactured by Tosoh Corporation, and polyethylene glycol (molecular weight of about 12,000, manufactured by Polymer Laboratory) 4,000, and 1,000).

<Measurement of imidation ratio>
20 mg of the polyimide powder is placed in an NMR sample tube (NMR sampling tube standard φ5 manufactured by Kusano Science Co., Ltd.), and 1.0 ml of deuterated dimethyl sulfoxide (DMSO-d ₆ , 0.05 mass% TMS mixture) is added thereto. And completely dissolved. The solution was subjected to proton NMR measurement at 500 MHz using an NMR measuring device (JNW-ECA500, manufactured by JEOL Datum). The imidation ratio is determined based on a proton derived from a structure that does not change before and after imidation, as a reference proton. The peak integrated value of this proton and the proton peak derived from the NH group of the amic acid appearing around 9.5 to 10.0 ppm are determined. It was determined by the following formula using the integrated value. In the following formula, x is the integrated value of the proton peak derived from the NH group of the amic acid, y is the integrated value of the peak of the reference proton, α is the proton of the NH group of the amic acid in the case of polyamic acid (imidation ratio is 0%). This is a ratio of the number of reference protons to one.
Imidation ratio (%) = (1−α · x / y) × 100

<Synthesis Example 7>
BODA (10.0 g, 40.0 mmol), DA-1 (15.2 g, 40.0 mmol), DA-2 (4.85 g, 20.0 mmol), and DA-3 (13.2 g, 40.0 mmol) Was dissolved in NMP (164.4 g) and reacted at 60 ° C. for 3 hours. Next, CBDA (11.5 g, 58.6 mmol) and NMP (54.8 g) were added and reacted at 40 ° C. for 10 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (250 g) and diluting it to 6.5% by mass, acetic anhydride (46.4 g) and pyridine (14.4 g) were added as imidation catalysts and reacted at 70 ° C. for 3 hours. Was. This reaction solution was poured into methanol (2900 g), 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 A. The imidation ratio of this polyimide was 73%, Mn was 13,000, and Mw was 39000.
NMP (48.8 g) was added to the obtained polyimide powder A (10.0 g) and dissolved by stirring at 70 ° C. for 12 hours. To this solution, 10.0 g of 3AMP (1 wt% NMP solution), NMP (31.2 g), and BCS (66.7 g) were added, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal aligning agent A1.

<Synthesis Example 8>
BODA (18.0 g, 72.0 mmol), DA-1 (13.7 g, 36.0 mmol), DA-2 (8.72 g, 36.0 mmol), and DBA (7.30 g, 48.0 mmol) were added to NMP. (173.5 g) and reacted at 60 ° C. for 3 hours. Thereafter, PMDA (10.1 g, 46.3 mmol) and NMP (57.8 g) were added and reacted at room temperature for 10 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (250 g) and diluting it to 10% by mass, acetic anhydride (52.6 g) and pyridine (40.8 g) were added as imidation catalysts, and reacted at 80 ° C. for 4 hours. This reaction solution was poured into methanol (2900 g), 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 B. The imidation ratio of this polyimide was 77%, Mn was 12,000, and Mw was 35,000. A liquid crystal aligning agent B1 was obtained in the same manner as in Synthesis Example 7, except that polyimide powder B (10.0 g) was used instead of polyimide powder A.

<Synthesis example 9>
To 70.0 g of the liquid crystal aligning agent A1 obtained in Synthesis Example 7, 30.0 g of the liquid crystal aligning agent B1 obtained in Synthesis Example 8 was added, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal aligning agent C1. Was.

<Synthesis example 10>
BODA (6.51 g, 26.0 mmol), DA-1 (14.8 g, 38.9 mmol), and DBA (13.9 g, 91.0 mmol) were dissolved in NMP (165.3 g) and heated at 60 ° C. The reaction was performed for 3 hours. Thereafter, CBDA (19.9 g, 101.5 mmol) and NMP (55.1 g) were added, and reacted at 40 ° C. for 12 hours to obtain a polyamic acid solution.
After NMP was added to the polyamic acid solution (250 g) to dilute it to 6.5% by mass, acetic anhydride (59.7 g) and pyridine (18.5 g) were added as imidation catalysts, and the mixture was reacted at 50 ° C. for 3 hours. . This reaction solution was poured into methanol (2900 g), 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 D. The imidation ratio of this polyimide was 75%, Mn was 12,000, and Mw was 32,000. Liquid crystal aligning agent D1 was obtained in the same manner as in Synthesis Example 7, except that polyimide powder D (10.0 g) was used instead of polyimide powder A.

<Synthesis Example 11>
To 70.0 g of the liquid crystal aligning agent A1 obtained in Synthesis Example 7, 30.0 g of the liquid crystal aligning agent D1 obtained in Synthesis Example 10 was added, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal aligning agent E1. Was.

<Synthesis Example 12>
BODA (10.0 g, 40.0 mmol), DA-1 (19.0 g, 50.0 mmol), and DA-3 (16.5 g, 50.0 mmol) were dissolved in NMP (171.1 g), The reaction was performed at a temperature of 3 ° C. for 3 hours. Thereafter, CBDA (11.5 g, 58.6 mmol) and NMP (57.0 g) were added and reacted at 40 ° C. for 12 hours to obtain a polyamic acid solution.
After NMP was added to this polyamic acid solution (250 g) to dilute it to 6.5% by mass, acetic anhydride (44.5 g) and pyridine (13.8 g) were added as imidation catalysts, and the mixture was reacted at 70 ° C. for 3 hours. . This reaction solution was poured into methanol (2900 g), 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 F. The imidation ratio of this polyimide was 73%, Mn was 14,000, and Mw was 38,000. A liquid crystal aligning agent F1 was obtained in the same manner as in Synthesis Example 7, except that polyimide powder F (10.0 g) was used instead of polyimide powder A.

<Synthesis Example 13>
To 70.0 g of the liquid crystal aligning agent F1 obtained in Synthesis Example 12, 30.0 g of the liquid crystal aligning agent B1 obtained in Synthesis Example 8 was added, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal aligning agent G1.

<Synthesis Example 14>
BODA (10.0 g, 40.0 mmol), DA-1 (15.2 g, 40.0 mmol), DA-3 (9.91 g, 30.0 mmol), and DA-5 (7.93 g, 30.0 mmol) Was dissolved in NMP (163.7 g) and reacted at 60 ° C. for 3 hours. Thereafter, CBDA (11.5 g, 58.6 mmol) and NMP (54.6 g) were added and reacted at 40 ° C. for 10 hours to obtain a polyamic acid solution.
After NMP was added to the polyamic acid solution (250 g) to dilute it to 6.5% by mass, acetic anhydride (46.5 g) and pyridine (14.4 g) were added as imidation catalysts and reacted at 70 ° C. for 3 hours. Was. This reaction solution was poured into methanol (2900 g), 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 H. The imidation ratio of this polyimide was 74%, Mn was 16,000, and Mw was 45000. A liquid crystal aligning agent H1 was obtained in the same manner as in Synthesis Example 7, except that polyimide powder H (10.0 g) was used instead of polyimide powder A.

<Synthesis Example 15>
TCA (1.35 g, 6.0 mmol), DA-1 (2.28 g, 6.0 mmol), and DA-3 (2.97 g, 9.0 mmol) were dissolved in NMP (24.9 g), The reaction was carried out at 3 ° C. for 3 hours. Thereafter, CBDA (1.74 g, 8.9 mmol) and NMP (8.3 g) were added and reacted at room temperature for 10 hours to obtain a polyamic acid solution.
After NMP was added to this polyamic acid solution (36 g) to dilute it to 6% by mass, acetic anhydride (4.0 g) and pyridine (2.1 g) were added as imidation catalysts, and reacted at 50 ° C. for 3 hours. This reaction solution was poured into methanol (700 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 I. The imidation ratio of this polyimide was 60%, Mn was 20,000, and Mw was 43,000.
NMP (44.0 g) was added to the obtained polyimide powder I (6.0 g), and the mixture was stirred at 50 ° C. for 5 hours to be dissolved. 6.0 g of 3AMP (1 wt% NMP solution), NMP (14.0 g) and BCS (30.0 g) were added to this solution, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal aligning agent I1.

<Synthesis Example 16>
BODA (2.00 g, 8.0 mmol), DA-3 (4.63 g, 14.0 mmol), and DA-4 (2.61 g, 6.0 mmol) were dissolved in NMP (34.5 g), and dissolved in NMP (34.5 g). The reaction was carried out at a temperature of 3 ° C. for 3 hours. Thereafter, CBDA (2.27 g, 11.6 mmol) and NMP (11.5 g) were added and reacted at room temperature for 10 hours to obtain a polyamic acid solution.
After NMP was added to this polyamic acid solution (50 g) to dilute it to 6% by mass, acetic anhydride (5.3 g) and pyridine (2.7 g) were added as imidation catalysts and reacted at 50 ° C. for 3 hours. This reaction solution was poured into methanol (700 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 J. The imidation ratio of this polyimide was 60%, Mn was 17000, and Mw was 35,000. A liquid crystal aligning agent J1 was obtained in the same manner as in Synthesis Example 15, except that polyimide powder J (10.0 g) was used instead of polyimide powder I.

<Synthesis Example 17>
BODA (1.30 g, 5.2 mmol), DA-6 (2.03 g, 3.9 mmol), and DA-3 (3.00 g, 9.1 mmol) were dissolved in NMP (23.5 g), and dissolved in NMP (23.5 g). The reaction was performed at a temperature of 3 ° C. for 3 hours. Thereafter, CBDA (1.43 g, 7.3 mmol) and NMP (7.8 g) were added and reacted at room temperature for 10 hours to obtain a polyamic acid solution.
After NMP was added to this polyamic acid solution (36 g) to dilute it to 6% by mass, acetic anhydride (3.6 g) and pyridine (1.9 g) were added as imidization catalysts and reacted at 50 ° C. for 3 hours. This reaction solution was poured into methanol (700 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 K. The imidation ratio of this polyimide was 60%, Mn was 16,000, and Mw was 36,000. A liquid crystal aligning agent K1 was obtained in the same manner as in Synthesis Example 15, except that polyimide powder K (10.0 g) was used instead of polyimide powder I.

(Example 1)
To 10.0 g of the liquid crystal aligning agent C1 obtained in Synthesis Example 9, 0.042 g (7% by mass based on the solid content) of the polymerizable compound RM1 obtained in Synthesis Example 1 was added, and the mixture was added at room temperature for 3 hours. The liquid crystal aligning agent L1 was prepared by stirring and dissolving.

(Example 2)
A liquid crystal aligning agent L2 was prepared in the same manner as in Example 1, except that the amount of the polymerizable compound RM1 was changed to 0.06 g (10% by mass based on the solid content).
(Example 3)
A liquid crystal aligning agent L3 was prepared in the same manner as in Example 1, except that RM2 obtained in Synthesis Example 2 was used instead of the polymerizable compound RM1.
(Example 4)
A liquid crystal aligning agent L4 was prepared in the same manner as in Example 1, except that RM3 obtained in Synthesis Example 3 was used instead of the polymerizable compound RM1.

(Example 5)
A liquid crystal aligning agent M1 was prepared in the same manner as in Example 1, except that the liquid crystal aligning agent A1 obtained in Synthesis Example 7 was used instead of the liquid crystal aligning agent C1.
(Example 6)
A liquid crystal aligning agent N1 was prepared in the same manner as in Example 1, except that the liquid crystal aligning agent E1 obtained in Synthesis Example 11 was used instead of the liquid crystal aligning agent C1.
(Example 7)
A liquid crystal aligning agent O1 was prepared in the same manner as in Example 1 except that the liquid crystal aligning agent G1 obtained in Synthesis Example 13 was used instead of the liquid crystal aligning agent C1.
(Example 8)
A liquid crystal aligning agent P1 was prepared in the same manner as in Example 1, except that the liquid crystal aligning agent H1 obtained in Synthesis Example 14 was used instead of the liquid crystal aligning agent C1.

(Example 9)
A liquid crystal aligning agent Q1 was prepared in the same manner as in Example 1 except that the liquid crystal aligning agent I1 obtained in Synthesis Example 15 was used instead of the liquid crystal aligning agent C1.
(Example 10)
A liquid crystal aligning agent R1 was prepared in the same manner as in Example 1, except that the liquid crystal aligning agent J1 obtained in Synthesis Example 16 was used instead of the liquid crystal aligning agent C1.
(Example 11)
A liquid crystal aligning agent S1 was prepared in the same manner as in Example 1, except that the liquid crystal aligning agent K1 obtained in Synthesis Example 17 was used instead of the liquid crystal aligning agent C1.

(Comparative Example 1)
A liquid crystal aligning agent L5 was prepared in the same manner as in Example 1, except that RM4 obtained in Synthesis Example 4 was used instead of the polymerizable compound RM1.
(Comparative Example 2)
A liquid crystal aligning agent L6 was prepared in the same manner as in Example 1, except that RM5 obtained in Synthesis Example 5 was used instead of the polymerizable compound RM1.
(Comparative Example 3)
A liquid crystal aligning agent L7 was prepared in the same manner as in Example 2, except that RM5 obtained in Synthesis Example 5 was used instead of the polymerizable compound RM1.
(Comparative Example 4)
A liquid crystal aligning agent L8 was prepared in the same manner as in Example 1, except that RM6 obtained in Synthesis Example 6 was used instead of the polymerizable compound RM1.
(Comparative Example 5)
A liquid crystal aligning agent L9 was prepared in the same manner as in Example 2, except that RM6 obtained in Synthesis Example 6 was used instead of the polymerizable compound RM1.

<Production of liquid crystal cell>
(Example 12)
Using the liquid crystal aligning agent L1 obtained in Example 1, a liquid crystal cell was manufactured in the following procedure.
The liquid crystal aligning agent L1 is spin-coated on the IZO surface of a 4-pixel IZO electrode substrate having a pixel size of 87 μm × 89 μm and an IZO electrode pattern (fishbone) having a line / space of 3 μm each. Dried for 90 seconds on a hot plate. Thereafter, baking was performed in a hot air circulation oven at 200 ° C. for 20 minutes to form a liquid crystal alignment film having a thickness of 100 nm.
Further, the liquid crystal aligning agent L1 was spin-coated on the ITO surface of the ITO electrode substrate on which no electrode pattern was formed, and dried on a hot plate at 80 ° C. for 90 seconds. Thereafter, baking was performed in a hot air circulating oven at 200 ° C. for 20 minutes to form a liquid crystal alignment film having a thickness of 100 nm.
With respect to the two substrates, 3.3 μm bead spacers were sprayed on the liquid crystal alignment film of one of the substrates, and then a sealant (solvent-type thermosetting epoxy resin) was printed thereon. Next, the other substrate was bonded to the previous substrate with the surface on the side where the liquid crystal alignment film was formed facing inside, and then the sealant was cured to form an empty cell. Liquid crystal MLC-6608 (manufactured by Merck) was injected into the empty cell by a vacuum injection method. Thereafter, the liquid crystal cell 1 was prepared by placing it in a hot-air circulating oven at 120 ° C. for 1 hour to perform a liquid crystal reorientation treatment.

"Observation of bright spots in liquid crystal cells"
The bright point in the obtained liquid crystal cell 1 was observed by the following method. The liquid crystal cell 1 immediately after the reorientation treatment was left at room temperature for 2 days, and thereafter, the liquid crystal cell was observed with a polarizing microscope. When the solubility of the polymerizable compound in the liquid crystal is low, it is considered that the compound easily precipitates in the liquid crystal cell and a bright spot is generated. A sample in which no luminescent spot is generated is regarded as good, and a sample in which a luminescent spot is generated is regarded as defective.

"Evaluation of residual images derived from AC"
An afterimage derived from AC of the obtained liquid crystal cell 1 was measured by the following method.
With a DC voltage of 15 V applied to the liquid crystal cell 1, 6 J / cm ^{2 of} UV was irradiated from the outside of the liquid crystal cell 1 through a 365 nm band-pass filter. The UV illuminance was measured using UV-MO3A manufactured by ORC. Thereafter, with no voltage applied, UV (UV lamp: FLR40SUV32 / A-1) was irradiated for 30 minutes using a UV-FL irradiation device manufactured by Toshiba Lighting & Technology Corporation. A polarizing film was attached to both surfaces of the liquid crystal cell 1 in a crossed Nicol state such that the polarization axis of the polarizing film and the director of the liquid crystal were at 45 °. Of the four pixels, a rectangular wave of 30 Hz and 20 Vpp was applied to only one arbitrary pixel and only one pixel at a diagonal thereof for 70 hours. After the voltage was turned off, the electrodes of the liquid crystal cell were connected and short-circuited. Thereafter, the liquid crystal cell was placed on a backlight, and the luminance of the voltage applied pixel and the luminance of the non-voltage applied pixel were visually compared. It is considered that the luminance difference between the voltage-applied pixel and the non-voltage-applied pixel was small when the afterimage characteristics were good. The cell was observed from the front.

"Measurement of pretilt angle"
In the production of the liquid crystal cell 1, instead of an IZO electrode substrate having four pixels, an ITO electrode substrate having a pixel size of 100 μm × 300 μm and an ITO electrode pattern having a line / space of 5 μm each was used. A liquid crystal cell 2 was produced in the same manner as in the production of the liquid crystal cell 1, except that a 4 μm bead spacer was used instead of the bead spacer.
With a DC voltage of 15 V applied, the liquid crystal cell 2 was irradiated with 6 J / cm ^{2 of} UV through a 365 nm band-pass filter from the outside of the liquid crystal cell 2. The UV illuminance was measured using UV-MO3A manufactured by ORC. Thereafter, with no voltage applied, UV (UV lamp: FLR40SUV32 / A-1) was irradiated for 30 minutes using a UV-FL irradiation apparatus (manufactured by Toshiba Lighting & Technology Corp.).
The pretilt angle of the pixel portion after the UV irradiation was measured using an LCD analyzer LCA-LUV42A (manufactured by Meisho Technica).

(Examples 13 to 22, Comparative Examples 6 to 10)
A liquid crystal cell was prepared by performing the same operation as in Example 12 except that each liquid crystal aligning agent shown in Table 2 was used instead of the liquid crystal aligning agent L1, and the above-described evaluation was performed on each liquid crystal cell. . The results are summarized in Table 2.

[Table 2]
_______________________________________________
Liquid crystal aligning agent Polymerizable compound Liquid crystal cell Pretilt angle derived from AC
Bright point in mass% Afterimage characteristics (°)
_______________________________________________
Example 12 L1 RM1 7 good good 89.1
Example 13 L2 RM1 10 Good Good 88.8
Example 14 L3 RM2 7 good good 89.1
Example 15 L4 RM3 7 Good Good 89.0
Example 16 M1 RM1 7 good good 88.8
Example 17 N1 RM1 7 good good 89.0
Example 18 O1 RM17 Good Good 88.8
Example 19 P1 RM1 7 good good 88.7
Example 20 Q1 RM1 7 good good 88.6
Example 21 R1 RM1 7 good good 88.6
Example 22 S1 RM1 7 good good 88.6
Comparative Example 6 L5 RM4 7 Poor Good 89.2
Comparative Example 7 L6 RM5 7 Good Bad 89.3
Comparative Example 8 L7 RM5 10 Good Bad 89.0
Comparative Example 9 L8 RM67 Good Bad 89.6
Comparative Example 10 L9 RM6 10 Good Bad 89.4
_______________________________________________

From the results of the bright spot observations of Examples 12 to 15 and Comparative Example 6, it can be seen that the solubility in the liquid crystal is improved by making the molecular structure of the polymerizable compound used asymmetric.
Also, from the comparison between Examples 12, 14, and 15 and Comparative Examples 7 and 8, the method for asymmetrizing the molecular structure of the polymerizable compound of the present invention (the above-described methods 1 and 2) shows that the benzene ring has left-right asymmetry. It can be seen that the afterimage characteristic derived from AC is superior to the method of introducing a substituent (method 4).
Similarly, from the results of Examples 12, 14 and 15 and Comparative Examples 9 and 10, the method for asymmetrizing the molecular structure of the polymerizable compound of the present invention is compared with the method (Method 3) in which the left and right polymerizable groups are different. However, it can be seen that the afterimage characteristics derived from AC are excellent.
This is presumably because the stacking of the ring structure is stronger than that of a methacrylic compound in which one of the polymerizable groups does not have a ring structure, and the resulting polymer network is more rigid.

A liquid crystal display device having a liquid crystal alignment film formed using the liquid crystal alignment agent of the present invention has a high liquid crystal response speed, and can be widely used as a vertical alignment type liquid crystal display device such as a PSA type liquid crystal display. .
The entire contents of the specification, claims and abstract of Japanese Patent Application No. 2015-22123 filed on Feb. 6, 2015 are incorporated herein by reference as the disclosure of the specification of the present invention. Things.

Claims (11)

A polymerizable compound (1) represented by the following formula (1):
A polyimide precursor obtained from a diamine containing a diamine having a side chain for vertically aligning liquid crystal and a diamine having a photoreactive side chain , and a polyimide precursor obtained by imidizing the polyimide precursor, selected from the group consisting of: At least one polymer;
The liquid crystal aligning agent characterized by containing.

(Wherein, X ¹ and X ² each independently represent a bonding group selected from an ether bond and an ester bond, and S ¹ and S ² each independently represent a straight-chain alkylene having 2 to 9 carbon atoms. Represents a group, and S ¹ , X ¹ , X ² and S ² are selected such that the molecule is bilaterally asymmetric.) The polyimide precursor is a polyamic acid obtained by reacting a diamine containing a diamine having a side chain for vertically aligning the liquid crystal and a diamine having a photoreactive side chain, and tetracarboxylic dianhydride. The liquid crystal aligning agent according to claim 1 . The polymerizable compound (1), the liquid crystal alignment agent according to claim 1 or 2 is an alkylene group having S ¹ and the number of carbon S ² are different from each other. The polymerizable compound (1), either one of X ¹ and X ² is an ether bond, or the other is an ester bond, an ester bond which X ¹ binds S ¹ carbonyl side, X ² There the liquid crystal alignment agent according to any one of claims 1 to 3 is an ester bond to bond to S ² oxygen atoms side. The liquid crystal aligning agent according to any one of claims 1 to 4, wherein the polymerizable compound (1) is a compound represented by any one of the following formulas RM1 to RM3.

A liquid crystal alignment film formed by using the liquid crystal aligning agent according to any one of claims 1-5.   A liquid crystal display device comprising the liquid crystal alignment film according to claim 6. At least one selected from the group consisting of a polyimide precursor obtained from a diamine having a diamine having a side chain for vertically aligning liquid crystal and a diamine having a photoreactive side chain and a polyimide obtained by imidizing the polyimide precursor. A liquid crystal alignment agent containing one polymer is applied on two substrates to form a liquid crystal alignment layer, and the two substrates are arranged so that the liquid crystal alignment layers face each other. A method of manufacturing a vertical alignment type liquid crystal display element in which a liquid crystal layer is sandwiched between the liquid crystal layers and ultraviolet rays are applied while applying an electric field to the liquid crystal layer,
A method for manufacturing a liquid crystal display device, comprising: adding a polymerizable compound represented by the following formula (1) to the liquid crystal alignment agent.

(Wherein, X ¹ and X ² each independently represent a bonding group selected from an ether bond and an ester bond, and S ¹ and S ² each independently represent a straight-chain alkylene having 2 to 9 carbon atoms. Represents a group, and S ¹ , X ¹ , X ² and S ² are selected such that the molecule is bilaterally asymmetric.) The method according to claim 8 , wherein in the polymerizable compound (1), S ¹ and S ² are alkylene groups having different carbon numbers. The polymerizable compound (1), either one of X ¹ and X ² is an ether bond, or the other is an ester bond, an ester bond which X ¹ binds S ¹ carbonyl side, X ² the method according to claim 8 or 9 but an ester bond to bond to S ² oxygen atoms side. The method for producing a liquid crystal alignment agent according to any one of claims 8 to 10 , wherein the polymerizable compound (1) is any one of the following formulas RM1 to RM3.