JP5962512B2 - Liquid crystal aligning agent and liquid crystal aligning film - Google Patents

Description

  The present invention relates to a liquid crystal aligning agent for obtaining a liquid crystal display element that exhibits a high and stable pretilt angle and has little residual charge accumulation, and a liquid crystal aligning film obtained from the liquid crystal aligning agent.

  In a liquid crystal display element used for a liquid crystal television, a liquid crystal display, and the like, a liquid crystal alignment film for controlling the alignment state of liquid crystals is usually provided in the element. Conventionally, as the liquid crystal alignment film, a polyimide-based liquid crystal alignment film obtained by applying a liquid crystal alignment agent mainly composed of a polyimide precursor such as polyamic acid (polyamic acid) or a solution of soluble polyimide to a glass substrate or the like and baking it is mainly used. It is used.

  As liquid crystal display elements have become higher in definition, liquid crystal alignment films have high liquid crystal alignment characteristics and stable pretilt angles in addition to the demands for suppressing the decrease in contrast and reducing the afterimage phenomenon. Characteristics such as a voltage holding ratio, a small residual charge when a DC voltage is applied, and / or a quick relaxation of a residual charge accumulated by a DC voltage are becoming increasingly important.

For polyimide-based liquid crystal alignment films, in order to meet the above requirements, liquid crystal aligning agents blended with two or more types of polyamic acids having different characteristics and imidized polymers thereof are known.
For example, a liquid crystal aligning agent (Patent Document 1 and Patent Document 2) containing two or more types of polyamic acids having different surface tensions and two or more types of polymers thereof, a polymer having the largest imidization rate and the smallest imidization rate A liquid crystal aligning agent (Patent Document 3) containing at least two kinds of polymers selected from soluble polyimide and polyamic acid having a difference in imidization ratio of the polymer of 5% or more, a low-polarity side chain-containing polyamic acid resin, and A liquid crystal aligning agent (Patent Document 4) containing a polyamic acid having a specific structure has been reported.

Japanese Unexamined Patent Publication No. 8-43831 Japanese Unexamined Patent Publication No. 8-325573 Japanese Unexamined Patent Publication No. 9-297312 Japanese Unexamined Patent Publication No. 2006-124626

  However, in recent years, liquid crystal televisions with large screens and high-definition are mainly used, and the demand for afterimages has become more severe, and characteristics that can withstand long-term use in harsh usage environments are required. At the same time, various characteristics of the liquid crystal alignment film to be used are required to have better characteristics and higher reliability than the conventional ones. A liquid crystal aligning agent containing a polyamic acid or an imidized polymer of the polyamic acid is not compatible with this.

That is, the formation reaction of the polyamic acid used for forming the liquid crystal aligning agent is an equilibrium reaction, and an amide exchange reaction proceeds in the solution. Therefore, even in a liquid crystal aligning agent having a composition in which two or more kinds of polyamic acids having different characteristics are mixed, an amide exchange reaction proceeds in the process of preparation, storage, coating, and baking, and the polymer composition is averaged. As a result, the pretilt angle becomes lower than when the side chain-containing component is used alone, and the desired pretilt angle cannot be expressed unless the ratio of the side chain-containing component is increased.
However, when the ratio of the side chain-containing component is increased, there arises a problem that the accumulation of direct current charge is increased. Therefore, it is difficult to solve the above problems with a liquid crystal aligning agent in which polyamic acids are mixed or soluble polyimide and polyamic acid are mixed.

On the other hand, the above amide exchange does not occur in a liquid crystal aligning agent containing polyimide obtained by imidizing 100% of each polyamic acid. However, in a liquid crystal aligning agent using a polyimide with an imidization rate of 100%, characteristics such as a solubility problem of polyimide and a deterioration in printability when a liquid crystal aligning film is formed on a substrate from the liquid crystal aligning agent are deteriorated. .
The present invention is not accompanied by the above-mentioned problems, in addition to excellent liquid crystal orientation and stable pretilt angle expression, a high voltage holding ratio, a small residual charge when a DC voltage is applied, and / or An object of the present invention is to provide a liquid crystal aligning agent from which a liquid crystal alignment film having characteristics such as quick relaxation of accumulated residual charges due to a DC voltage can be obtained.

  The present inventor has conducted extensive research to achieve the above object, and as a result, the polyamic acid ester obtained by converting the free acid structure of the polyamic acid into an ester structure is an irreversible reaction. We focused on the fact that no such amide exchange reaction occurred. As a constituent component of the liquid crystal aligning agent, a polyamic acid that does not undergo an amide exchange reaction is introduced with a pretilt angle-expressing side chain structure to form a pretilt angle-expressing component, and a polyamic acid that has an excellent function of suppressing charge accumulation is charged. It has been found that the above-mentioned problems can be solved by a liquid crystal aligning agent that is a component that suppresses the accumulation of the above.

The present invention is based on the above findings and has the following gist.
1. A polyamic acid ester having a structural unit of the following formula (1), a polyamic acid having a structural unit of the following formula (2), and an organic solvent, wherein the polyamic acid ester has the following formulas (3) and (4) And a liquid crystal aligning agent having a side chain structure having a pretilt angle developing ability, comprising at least one selected from the group consisting of (5) .

（式中、Ｘ_１、X_２は４価の有機基であり、Ｙ_１、Ｙ_２は２価の有機基であり、Ｒ_１は炭素数１〜５のアルキル基であり、A_１、A_２は独立して水素原子、炭素数１〜１０のアルキル基、又は炭素数２〜１０の、アルケニル基若しくはアルキニル基である。）

Wherein X ₁ and X ₂ are tetravalent organic groups, Y ₁ and Y ₂ are divalent organic groups, R ₁ is an alkyl group having 1 to 5 carbon atoms, and A ₁ , A ₂ are independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or 2 to 10 carbon atoms, Ru alkenyl or alkynyl group der.)

(In Formula (3), Z < ₁ > and Z < ₃ > are at least 1 sort (s) chosen from the group which consists of a single bond or following formula (B-1)-(B-16) each independently. , Z ₂ may have a single bond or a substituent, from a group consisting of an alkylene group having 1 to 10 carbon atoms, an alkenylene group having 2 to 10 carbon atoms, an alkynylene group having 2 to 10 carbon atoms, and an arylene group. Z ₄ is at least one selected, and Z ₄ is an optionally substituted aliphatic ring having 3 to 20 carbon atoms, an aromatic ring having 6 to 30 carbon atoms and a heterocyclic ring having 1 to 20 carbon atoms. At least one divalent cyclic group selected from the group consisting of the above, or a divalent organic group having 12 to 25 carbon atoms having a steroid skeleton, and Z ₅ may have a substituent, and the number of carbon atoms may be 3 -20 aliphatic ring, C6-C30 aromatic ring and C1-C20 Is at least one divalent cyclic group selected from the group consisting of heterocycle, a is an integer of 0 to 4, Z ₆ may have a substituent, an alkyl having 1 to 18 carbon atoms And at least one selected from the group consisting of a group, a fluorine-containing alkyl group having 1 to 18 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms, and a fluorine-containing alkoxyl group having 1 to 18 carbon atoms, b is 1 to 4 Is an integer.
In Formula (4), W ₁ may have a substituent, and may be substituted from a group consisting of an aliphatic ring having 3 to 20 carbon atoms, an aromatic ring having 6 to 30 carbon atoms, and a heterocyclic ring having 1 to 20 carbon atoms. Is at least one selected trivalent cyclic group or a trivalent organic group having 12 to 25 carbon atoms having a steroid skeleton, W ₂ has the same definition as Z _{5 in} formula (3), and c is W ₃ is an integer of 0 to 4, W ₃ is the same definition as Z ₂ of formula (3), W ₄ is the same definition as Z ₆ of formula (3), d is an integer of 0 to 4, e is an integer of 1-4.
In Formula (5), E ₁ has the same definition as Z ₁ and Z ₃ in Formula (3), E ₂ is an alkyl group having 4 to 30 carbon atoms or a fluorine-containing alkyl group, and f is 1 to It is an integer of 4. )

（式（Ｂ−１）〜（Ｂ−１６）中、Ｒ_２はそれぞれ独立して水素原子、又は置換基を有してもよい炭素数１〜１０のアルキル基、アルケニル基、アルキニル基、アリール基、又は、それらの組み合わせである。）
２．前記ポリアミック酸エステルの含有量と前記ポリアミック酸の含有量が、（ポリアミック酸エステルの含有量／ポリアミック酸の含有量）の質量比率で、１／９〜９／１である上記１に記載の液晶配向剤。
３．前記ポリアミック酸エステル及びポリアミック酸の合計含有量が、有機溶媒に対して０．５〜１５質量％である上記１又は２に記載の液晶配向剤。
４．上記式（１）中、Ｙ_１の一部、又は全部が、上記式（３）〜（５）から選ばれる少なくとも１種類の構造を有する２価の有機基（Ｙ_１’）である上記１〜３のいずれかに記載の液晶配向剤。
５．上記Ｙ_１’の比率が、Ｙ_１全体に対して、１〜５０モル％である上記４に記載の液晶配向剤。
６．上記Ｙ_１’の構造が、下記式[１−１]〜[１−３]から選ばれる少なくとも１種類の構造である上記４に記載の液晶配向剤。

(In formulas (B-1) to (B-16), each R ₂ is independently a hydrogen atom or an optionally substituted alkyl group, alkenyl group, alkynyl group, aryl, which may have a substituent. Group or a combination thereof.)
2. 2. The liquid crystal according to 1 above, wherein the content of the polyamic acid ester and the content of the polyamic acid are 1/9 to 9/1 in a mass ratio of (content of polyamic acid ester / content of polyamic acid). Alignment agent.
3. The liquid crystal aligning agent of said 1 or 2 whose sum total content of the said polyamic acid ester and polyamic acid is 0.5-15 mass% with respect to the organic solvent.
4). In the above formula (1), part or all of Y ₁ is a divalent organic group (Y ₁ ′) having at least one structure selected from the above formulas (3) to (5). The liquid crystal aligning agent in any one of ~ 3 .
5. The ratio of the _{Y 1} 'is, for the entire _{Y 1,} liquid crystal alignment agent according to the 4 1 to 50 mol%.
6). 5. The liquid crystal aligning agent according to 4 above, wherein the structure of Y ₁ ′ is at least one structure selected from the following formulas [1-1] to [1-3].

（式［１−１］〜［１−３］中、Ａ_３及びＡ_４はそれぞれ独立して単結合、又は炭素数１〜１０のアルキル基であり、Ａ_５は単結合、又は炭素数１〜２０の２価の有機基であり、Ａ_６は窒素原子、又は炭素数１〜３０の３価の有機基であり、Ａ_７及びＡ_８はそれぞれ独立して炭素数１〜３０の２価の有機基であり、Ｚは上記式（３）又は上記式（５）で表される側鎖構造であり、Ｗは上記式（４）で表される側鎖構造である。）
７．上記式（１）及び（２）におけるＸ_１及びＸ_２が、それぞれ独立して、下記式で表される構造から選ばれる少なくとも１種類である上記１〜６に記載の液晶配向剤。

(In the formulas [1-1] to [1-3], A ₃ and A ₄ are each independently a single bond or an alkyl group having 1 to 10 carbon atoms, and A ₅ is a single bond or 1 carbon atom. Is a divalent organic group having ˜20, A ₆ is a nitrogen atom or a trivalent organic group having 1 to 30 carbon atoms, and A ₇ and A ₈ are each independently divalent having 1 to 30 carbon atoms. Z is a side chain structure represented by the above formula (3) or (5), and W is a side chain structure represented by the above formula (4).
7 . 7. The liquid crystal aligning agent according to the above 1 to 6 , wherein X ₁ and X ₂ in the formulas (1) and (2) are each independently at least one selected from the structures represented by the following formulas.

８．式（２）中、Ｙ_２が下記式で表される構造から選ばれる少なくとも１種類である請求項１〜７のいずれかに記載の液晶配向剤。

8). The liquid crystal aligning agent of according to any one of claims 1 to 7 at least one of the formula _(2), Y 2 is selected from structures represented by the following formula.

９．上記１〜８のいずれかに記載の液晶配向剤を塗布、焼成する液晶配向膜の製造方法。
１０．上記１〜８のいずれかに記載の液晶配向剤を塗布、焼成して得られる被膜に、偏光させた放射線を照射する液晶配向膜の製造方法。

9. The manufacturing method of the liquid crystal aligning film which apply | coats and bakes the liquid crystal aligning agent in any one of said 1-8 .
10. The manufacturing method of the liquid crystal aligning film which irradiates the polarized radiation to the film obtained by apply | coating and baking the liquid crystal aligning agent in any one of said 1-8 .

In the liquid crystal aligning agent provided by the present invention, since the pretilt angle is expressed by a polyamic acid ester that does not cause an amide exchange reaction, a highly stable pretilt angle is expressed by the predetermined content, Suppression of charge accumulation is performed by a polyamic acid having an excellent function, so that afterimages due to charge accumulation are small.
In addition, since the liquid crystal aligning agent of the present invention does not need to be imidized and polyimided in advance, the components contained in the liquid crystal aligning agent have high solubility, and are applied and printed when a liquid crystal aligning film is formed on a substrate. Excellent in properties. Furthermore, as described above, the liquid crystal aligning agent of the present invention does not cause an amide exchange reaction and the like, so the characteristics do not change during storage, so it has excellent storage stability and was used after storage for a long time. Even when stable, it maintains excellent characteristics.

<Polyamic acid ester>
The polyamic acid ester used in the present invention is a polyimide precursor, and is a polymer having a site capable of undergoing an imidation reaction shown below by heating.

本発明の液晶配向剤に含有されるポリアミック酸エステルは、下記式（１）で表される構造を有する。

The polyamic acid ester contained in the liquid crystal aligning agent of the present invention has a structure represented by the following formula (1).

In the formula (1), R ₁ is 1 to 5 carbon atoms, preferably 1 to 2 alkyl groups. In the polyamic acid ester, the temperature at which imidization proceeds increases as the number of carbon atoms in the alkyl group increases. Therefore, R ₁ is particularly preferably a methyl group from the viewpoint of ease of imidization by heat. In formula (1), A ₁ and A ₂ are each independently a hydrogen atom or an optionally substituted alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or an alkynyl group. It is. Specific examples of the alkyl group include methyl group, ethyl group, propyl group, butyl group, t-butyl group, hexyl group, octyl group, decyl group, cyclopentyl group, cyclohexyl group, and bicyclohexyl group. Examples of the alkenyl group include those obtained by replacing one or more CH—CH structures present in the above alkyl group with C═C structures, and more specifically, vinyl groups, allyl groups, 1-propenyl groups. , Isopropenyl group, 2-butenyl group, 1,3-butadienyl group, 2-pentenyl group, 2-hexenyl group, cyclopropenyl group, cyclopentenyl group, cyclohexenyl group and the like. Alkynyl groups include those in which one or more CH ₂ —CH ₂ structures present in the alkyl group are replaced with C≡C structures, and more specifically, ethynyl groups, 1-propynyl groups, 2 -A propynyl group etc. are mentioned.

The above alkyl group, alkenyl group, and alkynyl group may have a substituent as long as it has 1 to 10 carbon atoms as a whole, and may further form a ring structure with the substituent. In the present invention, the formation of a ring structure by a substituent means that the substituents or a substituent and a part of the mother skeleton are combined to form a ring structure.
Examples of such substituents are halogen groups, hydroxyl groups, thiol groups, nitro groups, aryl groups, organooxy groups, organothio groups, organosilyl groups, acyl groups, ester groups, thioester groups, phosphate ester groups, amide groups, alkyls. A group, an alkenyl group and an alkynyl group.

Examples of the halogen group as a substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
A phenyl group is mentioned as an aryl group which is a substituent. This aryl group may be further substituted with the other substituent described above.
The organooxy group which is a substituent can have a structure represented by OR. The R may be the same or different, and examples thereof include the alkyl group, alkenyl group, alkynyl group, and aryl group described above. These Rs may be further substituted with the substituent described above. Specific examples of the organooxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, and an octyloxy group.

As the organothio group which is a substituent, the structure represented by -S-R can be shown. Examples of R include the aforementioned alkyl group, alkenyl group, alkynyl group, aryl group, and the like. These Rs may be further substituted with the substituent described above. Specific examples of the organothio group include a methylthio group, an ethylthio group, a propylthio group, a butylthio group, a pentylthio group, a hexylthio group, a heptylthio group, and an octylthio group.
As the organosilyl group which is a substituent, a structure represented by -Si- (R) ₃ can be shown. The R may be the same or different, and examples thereof include the alkyl group, alkenyl group, alkynyl group, and aryl group described above. These Rs may be further substituted with the substituent described above. Specific examples of the organosilyl group include a trimethylsilyl group, a triethylsilyl group, a tripropylsilyl group, a tributylsilyl group, a tripentylsilyl group, a trihexylsilyl group, a pentyldimethylsilyl group, and a hexyldimethylsilyl group.

As an acyl group which is a substituent, the structure represented by -C (O) -R can be shown. Examples of R include the above-described alkyl group, alkenyl group, and aryl group. These Rs may be further substituted with the substituent described above. Specific examples of the acyl group include formyl group, acetyl group, propionyl group, butyryl group, isobutyryl group, valeryl group, isovaleryl group, benzoyl group and the like.
As an ester group which is a substituent, the structure represented by -C (O) O-R or -OC (O) -R can be shown. Examples of R include the aforementioned alkyl group, alkenyl group, alkynyl group, aryl group, and the like. These Rs may be further substituted with the substituent described above.
As a thioester group which is a substituent, the structure represented by -C (S) O-R or -OC (S) -R can be shown. Examples of R include the aforementioned alkyl group, alkenyl group, alkynyl group, aryl group, and the like. These Rs may be further substituted with the substituent described above.

As a phosphate group which is a substituent, the structure represented by -OP (O)-(OR) ₂ can be shown. The R may be the same or different, and examples thereof include the alkyl group, alkenyl group, alkynyl group, and aryl group described above. These Rs may be further substituted with the substituent described above.
As the amide group as a substituent, —C (O) NH ₂ , or —C (O) NHR, —NHC (O) R, —C (O) N (R) ₂ , —NRC (O) R The structure represented by can be shown. The R may be the same or different, and examples thereof include the alkyl group, alkenyl group, alkynyl group, and aryl group described above. These Rs may be further substituted with the substituent described above.

As A ₁ and A ₂ , in general, when a bulky structure is introduced, there is a possibility that the reactivity of the amino group and the liquid crystal orientation may be lowered. Therefore, the number of carbon atoms that may have a hydrogen atom or a substituent is 1 The alkyl group of ˜5 is more preferable, and a hydrogen atom, a methyl group or an ethyl group is particularly preferable.
In the present invention, the polyamic acid ester has a side chain structure (hereinafter also simply referred to as a side chain structure) having a pretilt angle expression ability. The side chain structure having the ability to develop a pretilt angle is a structure having the ability to align liquid crystal molecules in a state inclined at a certain angle with respect to the substrate, and is not limited as long as it has this ability. Examples of such structures are known as long-chain alkyl groups, long-chain fluoroalkyl groups, cyclic groups having an alkyl group or fluoroalkyl group at the terminal, steroid groups, and the like, which are also suitably used in the present invention. . The side chain structure may be directly bonded to the main chain of the polyamic acid ester, or may be bonded via a bonding group.
Examples of the side chain structure having a pretilt angle expression ability include structures represented by the following formulas (3) to (5).

In Formula (3), Z ₁ and Z ₃ are each independently a single bond, or at least one divalent selected from the group consisting of the following Formulas (B-1) to (B-16): Organic group. Among these, Z ₁ and Z ₃ are single bonds, B-1, B-3, B-4, B-5, B-6, B-7, B-11, B-13 because of ease of synthesis. Or B-16 is more preferred. In the following formulas B-1 to B-16, each R ₂ is independently a hydrogen atom or an optionally substituted alkyl group having 1 to 10 carbon atoms, an alkenyl group, an alkynyl group, an aryl group, Or a combination thereof.
Specific examples of the alkyl group, alkenyl group, alkynyl group, and aryl group are the same as those described above. The above alkyl group, alkenyl group, alkynyl group, and aryl group may have a substituent as long as it has 1 to 10 carbon atoms as a whole, and may further form a ring structure by the substituent. . Specific examples of each substituent include the same ones as described above.

In Formula (3), Z ₂ is a single bond or an optionally substituted alkylene group having 1 to 10 carbon atoms, an alkenylene group having 2 to 10 carbon atoms, or an alkynylene group having 2 to 10 carbon atoms, and arylene. It is at least one selected from the group consisting of groups. As said alkylene group, the structure remove | excluding one hydrogen atom from the said alkyl group is mentioned. More specifically, a methylene group, 1,1-ethylene group, 1,2-ethylene group, 1,2-propylene group, 1,3-propylene group, 1,4-butylene group, 1,2-butylene group 1,2-pentylene group, 1,2-hexylene group, 1,2-nonylene group, 1,2-dodecylene group, 2,3-butylene group, 2,4-pentylene group, 1,2-cyclopropylene Group, 1,2-cyclobutylene group, 1,3-cyclobutylene group, 1,2-cyclopentylene group, 1,2-cyclohexylene group, 1,2-cyclononylene group, 1,2-cyclododecylene group, etc. Is mentioned.

  The alkenylene group includes a structure in which one hydrogen atom is removed from the alkenyl group. More specifically, 1,1-ethenylene group, 1,2-ethenylene group, 1,2-ethenylenemethylene group, 1-methyl-1,2-ethenylene group, 1,2-ethenylene-1,1- Ethylene group, 1,2-ethenylene-1,2-ethylene group, 1,2-ethenylene-1,2-propylene group, 1,2-ethenylene-1,3-propylene group, 1,2-ethenylene-1, Examples include 4-butylene group and 1,2-ethenylene-1,2-butylene group. Examples of the alkynylene group include a structure in which one hydrogen atom is removed from the alkynyl group. More specifically, an ethynylene group, an ethynylene methylene group, an ethynylene-1,1-ethylene group, an ethynylene-1,2-ethylene group, an ethynylene-1,2-propylene group, an ethynylene-1,3-propylene group, Examples include ethynylene-1,4-butylene group, ethynylene-1,2-butylene group and the like.

The arylene group includes a structure in which one hydrogen atom is removed from the aryl group. More specifically, a 1,2-phenylene group, a 1,3-phenylene group, a 1,4-phenylene group, and the like can be given. The alkylene group, alkenylene group, alkynylene group, arylene group, and a group obtained by combining these may have a substituent as long as the number of carbon atoms is 1 to 10 as a whole, and further a ring structure depending on the substituent. May be formed. Specific examples of each substituent include the same ones as described above. Z ₂ is more preferably a single bond or an alkylene group having 2 to 6 carbon atoms.
In formula (3), Z ₄ is a group consisting of an optionally substituted aliphatic ring having 3 to 20 carbon atoms, an aromatic ring having 6 to 30 carbon atoms, and a heterocyclic ring having 1 to 20 carbon atoms. Or at least one divalent organic group selected from a C12 to C25 organic group having a steroid skeleton. Among these, a benzene ring, a cyclohexane ring, or a cyclic group having 12 to 25 carbon atoms having a steroid skeleton is more preferable. The divalent organic group may have a substituent as long as it has 4 to 30 carbon atoms as a whole, and may further form a ring structure with the substituent. Specific examples of each substituent include the same ones as described above, and more preferably a hydroxyl group, an alkyl group having 1 to 3 carbon atoms, an alkoxyl group having 1 to 3 carbon atoms, and 1 to 1 carbon atoms. 3 fluorine-containing alkyl groups, an amide group represented by —NHCOOR (where R is an alkyl group having 1 to 4 carbon atoms), a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, and a fluorine atom. .

In the formula (3), Z ₅ is a group consisting of an optionally substituted aliphatic ring having 3 to 20 carbon atoms, an aromatic ring having 6 to 30 carbon atoms, and a heterocyclic ring having 1 to 20 carbon atoms. At least one divalent cyclic group selected from the group consisting of: Of these, a benzene ring and a cyclohexane ring are more preferable. The above divalent cyclic group may have a substituent as long as it has 1 to 30 carbon atoms as a whole, and may further form a ring structure with the substituent. Specific examples of each substituent include the same ones as described above, and more preferably a hydroxyl group, an alkyl group having 1 to 3 carbon atoms, an alkoxyl group having 1 to 3 carbon atoms, and 1 to 1 carbon atoms. 3 fluorine-containing alkyl groups, an amide group represented by —NHCOOR (where R is an alkyl group having 1 to 4 carbon atoms), a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, and a fluorine atom. .

In Formula (3), a is an integer of 0-4, Preferably, it is an integer of 0-2.
In Formula (3), Z ₆ is an alkyl group having 1 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 18 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms, and a fluorine-containing alkoxyl group having 1 to 18 carbon atoms. Is at least one selected from the group consisting of Especially, a C1-C18 alkyl group, a C1-C10 fluorine-containing alkyl group, a C1-C18 alkoxyl group, or a C1-C10 fluorine-containing alkoxyl group is preferable. More preferably, they are a C1-C12 alkyl group or a C1-C12 alkoxyl group. More preferably, they are a C1-C9 alkyl group or a C1-C9 alkoxyl group. b is an integer of 1-4, Preferably it is an integer of 1-2.

In formula (4), W ₁ is a group consisting of an optionally substituted aliphatic ring having 3 to 20 carbon atoms, an aromatic ring having 6 to 30 carbon atoms, and a heterocyclic ring having 1 to 20 carbon atoms. Is a trivalent organic group selected from at least one kind of trivalent cyclic group or an organic group having 12 to 25 carbon atoms having a steroid skeleton. Among these, an organic group having 12 to 25 carbon atoms having a benzene ring, a cyclohexane ring, or a steroid skeleton is preferable. The trivalent organic group may have a substituent as long as it has 4 to 30 carbon atoms or 4 to 30 atoms as a whole, and may further form a ring structure with the substituent. Specific examples of each substituent include the same ones as described above, and more preferably a hydroxyl group, an alkyl group having 1 to 3 carbon atoms, an alkoxyl group having 1 to 3 carbon atoms, and 1 to 1 carbon atoms. 3 fluorine-containing alkyl groups, an amide group represented by —NHCOOR (where R is an alkyl group having 1 to 4 carbon atoms), a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, and a fluorine atom. .

Wherein (4), _{W 2} has the same definition as _{Z 5} in the formula (3). Of these, a benzene ring and a cyclohexane ring are preferable. The divalent organic group may have a substituent as long as it has 1 to 30 carbon atoms as a whole, and may further form a ring structure with the substituent. Specific examples of each substituent include the same ones as described above, and more preferably a hydroxyl group, an alkyl group having 1 to 3 carbon atoms, an alkoxyl group having 1 to 3 carbon atoms, and 1 to 1 carbon atoms. 3 fluorine-containing alkyl groups, an amide group represented by —NHCOOR (where R is an alkyl group having 1 to 4 carbon atoms), a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, and a fluorine atom. . c is an integer of 0 to 4, preferably an integer of 0 to 2.

In formula (4), W ₃ has the same definition as Z ₂ in formula (3) above. Among these, a single bond or an alkylene group having 2 to 6 carbon atoms is preferable. The alkylene group, alkenylene group, alkynylene group, arylene group, and a group obtained by combining these may have a substituent as long as the number of carbon atoms is 1 to 10 as a whole, and further a ring structure depending on the substituent. May be formed. Note that forming a ring structure with a substituent means that the substituents or a substituent and a part of the mother skeleton are bonded to form a ring structure. Specific examples of each substituent include the same ones as described above. d is an integer of 0 to 4, preferably an integer of 0 to 2.

In formula (4), W ₄ has the same definition as Z ₆ in formula (3) above. Especially, a C1-C18 alkyl group, a C1-C10 fluorine-containing alkyl group, a C1-C18 alkoxyl group, or a C1-C10 fluorine-containing alkoxyl group is preferable. More preferably, they are a C1-C12 alkyl group or a C1-C12 alkoxyl group. More preferably, they are a C1-C9 alkyl group or a C1-C9 alkoxyl group.
e is an integer of 1 to 4, preferably an integer of 1 to 2.

In formula (5), E ₁ is the same definition as Z ₁ and Z ₃ in formula (3), including preferred examples. E ₂ is a fluorine-containing alkyl group of the alkyl group, or a 4 to 30 carbon atoms having 4 to 30 carbon atoms. Of these, an alkyl group having 10 to 30 carbon atoms and a fluorine-containing alkyl group having 10 to 30 carbon atoms are preferable. f is an integer of 1 to 4, preferably an integer of 1 to 2.
The ability to develop the pretilt angle varies depending on the side chain structure described above, but generally, when the amount of the side chain structure contained in the polymer increases, a higher pretilt angle is expressed, and when the amount decreases, the pretilt angle decreases. Further, the side chain structure represented by the formula (3) or the formula (4) having a cyclic structure has a smaller content than the side chain structure represented by the formula (5) alone. There is a tendency to develop a high pretilt angle.

The polyamic acid ester having a side chain structure in the present invention can be obtained by reaction of a diamine and a tetracarboxylic acid derivative using a diamine having a side chain structure or a tetracarboxylic acid derivative having a side chain structure as a raw material.
Among these, a method using a diamine compound having a side chain structure is preferable from the viewpoint of easy synthesis of raw materials. That is, as the polyamic acid ester of the present invention, in the above formula (1), a part or all of Y ₁ which is a divalent organic group has a divalent organic group (hereinafter referred to as Y). ₁ ') is preferred. Examples of the structure of Y ₁ ′ include, but are not limited to, structures represented by the following formulas [1-1] to [1-3].

In formulas [1-1] to [1-3], A ₃ and A ₄ are each independently a single bond or an alkyl group having 1 to 10 carbon atoms, and A ₅ is a single bond or 1 to carbon atoms. 20 is a divalent organic group having 20 atoms, A ₆ is a nitrogen atom or a trivalent organic group having 1 to 30 carbon atoms, and A ₇ and A ₈ are each independently a divalent organic group having 1 to 30 carbon atoms. It is an organic group, Z is a side chain structure represented by the above formula (3) or (5), and W is a side chain structure represented by the above formula (4).
If a more specific example is given about the structure of Y ₁ ′, structures represented by the following formulas [2-1] to [2-51] can be given, but the structure is not limited thereto.

上記式［２−１］〜[２−３]中、Ｚ_７は、−Ｏ−、−ＯＣＨ_２−、−ＣＨ_２Ｏ−、−ＣＯＯＣＨ_２−、−ＣＨ_２ＯＣＯ−、−ＣＯＮＨ−、又は−ＮＨＣＯ−を示し、Ｚ_８は、炭素数１〜２２を有する、アルキル基、アルコキシ基、フッ素含有アルキル基又はフッ素含有アルコキシ基である。

In the above formulas [2-1] to [2-3], Z ₇ represents —O—, —OCH ₂ —, —CH ₂ O—, —COOCH ₂ —, —CH ₂ OCO—, —CONH—, or indicates -NHCO-, _{Z 8} have 1 to 22 carbon atoms, an alkyl group, alkoxy group, fluorine-containing alkyl group or fluorine-containing alkoxy group.

上記式［２−４］〜式［２−６］中、Ｚ_９は、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＯＣＨ_２−、−ＣＨ_２ＯＣＯ−、−ＣＨ_２Ｏ−、−ＯＣＨ_２−、−ＣＨ_２−、−ＣＯＮＨ−又は−ＮＨＣＯ−を示し、Ｚ_１０は、炭素数１〜２２を有する、アルキル基、アルコキシ基、フッ素含有アルキル基又はフッ素含有アルコキシ基である。

In the above formulas [2-4] to [2-6], Z ₉ represents —COO—, —OCO—, —COOCH ₂ —, —CH ₂ OCO—, —CH ₂ O—, —OCH ₂ —, —CH ₂ —, —CONH— or —NHCO— is shown, and Z ₁₀ is an alkyl group, an alkoxy group, a fluorine-containing alkyl group or a fluorine-containing alkoxy group having 1 to 22 carbon atoms.

上記式［２−７］及び式［２−８］中、Ｚ_１１は、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＯＣＨ_２−、−ＣＨ_２ＯＣＯ−、−ＣＨ_２Ｏ−、−ＯＣＨ_２−、−ＣＨ_２−、−ＮＨＣＯ−、−ＣＯＮＨ−又はＯ−を示し、Ｚ_１２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。

In the above formulas [2-7] and [2-8], Z ₁₁ represents —COO—, —OCO—, —COOCH ₂ —, —CH ₂ OCO—, —CH ₂ O—, —OCH ₂ —, —CH ₂ —, —NHCO—, —CONH— or O— is shown, and Z ₁₂ is 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. .

上記式［２−９］及び式［２−１０］中、Ｚ_１３は、炭素数３以上１２以下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 above formulas [2-9] and [2-10], Z ₁₃ is an alkyl group having 3 to 12 carbon atoms, and the cis-trans isomerism of 1,4-cyclohexylene is a trans isomer. is there.

上記式［２−１１］〜式［２−１３］中、Ｚ_１４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 above formulas [2-11] to [2-13], Z ₁₄ is an alkyl group having 3 to 12 carbon atoms, and the cis-trans isomerism of 1,4-cyclohexylene is a trans isomer. .

In the above formula [2-15], A ₉ and A ₁₀ are each independently —O— *, —COO— *, —OCO— *, —COOCH ₂ — *, —CH ₂ OCO— *, — CH ₂ O— *, —OCH ₂ — *, —CH ₂ — *, —CONH— * or —NHCO— * (where the bond with “*” is (CH ₂ ) a ₂ ), and A ₁₁ is a 1,4-cyclohexylene group or 1,4-phenylene group, A ₁₂ is an alkyl group having 3 to 20 carbon atoms which may be substituted with a fluorine atom, and a ₁ is 0 Or, it is an integer of 1, a ₂ is an integer of 2 to 10, and a ₃ is an integer of 0 or 1.

上記式［２−３６］〜式［２−４０］中、Ｅ_３は、炭素数４〜２２の、アルキル基、又はフッ素含有アルキル基である。

The formula [2-36] to the formula [2-40] in, _{E 3} is of 4 to 22 carbon atoms, an alkyl group, or a fluorine-containing alkyl group.

上記式［２−４１］〜式［２−４６］中、Ｗ_９は、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＮＨ−、−ＮＨＣＯ−、−ＣＨ_２−、−Ｏ−、−ＣＯ−又はＮＨ−を示し、Ｗ_１０は、炭素数１〜２２を有する、アルキル基又はフッ素含有アルキル基を示す。

In the above formulas [2-41] to [2-46], W ₉ represents —COO—, —OCO—, —CONH—, —NHCO—, —CH ₂ —, —O—, —CO— or NH. -And W ₁₀ represents an alkyl group or a fluorine-containing alkyl group having 1 to 22 carbon atoms.

上記式［２−４７］〜［２−５１］中、Ｗ_１１は単結合、又は炭素数１〜１０のアルキレン基であり、Ｗ_１２は炭素数１〜２２のアルキル基、アルコキシ基、又はフッ素含有アルキル基であり、Ｗ_１３は、−Ｏ−、−ＣＨ_２−、−ＮＨ−、−ＣＯ−、−ＳＯ_２−、又は−Ｓ−を示す。

In the above formulas [2-47] to [2-51], W ₁₁ is a single bond or an alkylene group having 1 to 10 carbon atoms, and W ₁₂ is an alkyl group, alkoxy group or fluorine having 1 to 22 carbon atoms. It is a containing alkyl group, and W ₁₃ represents —O—, —CH ₂ —, —NH—, —CO—, —SO ₂ —, or —S—.

The divalent organic group having a side chain structure represented by Y ₁ ′ may be one type or a liquid crystal alignment film depending on characteristics such as liquid crystal alignment, pretilt angle, voltage holding characteristics, and accumulated charge. Two or more types may be included. In order to achieve the object of the present invention, the structure of Y ₁ ′ is preferably contained in an amount of 1 to 50 mol%, more preferably 5 to 30 mol%, particularly with respect to the repeating unit of the polyamic acid ester. Preferably it is 5-20 mol%.
In the above formula (1), among Y ₁ , the divalent organic group not having the side chain structure (hereinafter also referred to as Y) is not particularly limited, and two or more types may be mixed. Good. If the specific example of Y is shown, the following (Y-1)-(Y-77) will be mentioned.

Among them, in order to obtain a good liquid crystal alignment property, it is preferable to introduce a highly linear diamine to the polyamic acid ester, a _{Y 1} is, Y-7, Y-10 , Y-11, Y-12 Y-13, Y-21, Y-22, Y-23, Y-25, Y-26, Y-27, Y-41, Y-42, Y-43, Y-44, Y-45, Y -46, Y-48, Y-61, Y-63, Y-64, Y-71, Y-72, Y-73, Y-74, Y-75 are more preferable. Moreover, in order to improve the solubility of a polymer, the diamine which has a bending structure is preferable, Y-2, Y-3, Y-4, Y-5, Y-8, Y-9, Y-11, Y -14, Y-16, Y-17, Y-20, Y-21, Y-22, Y-28, Y-29, Y-30, Y-31, Y-35, Y-37, Y-38 Y-40, Y-65, Y-66, Y-68 are more preferable.

In the above formula (1), X ₁ is a tetravalent organic group, and two or more kinds may be mixed, and the structure is not particularly limited. If Specific examples of _{X 1} in the polyamic acid ester, shown below (X-1) include ~ (X-46). Among these, X ₁ is X-1, X-2, X-3, X-4, X-5, X-6, X-8, X-16, X-19, X due to the availability of monomers. -21, X-25, X-26, X-27, X-28, X-32 or X-46 is preferred.

[Polyamic acid]
The polyamic acid used in the present invention is a polyimide precursor for obtaining a polyimide, and is a polymer having a portion capable of undergoing an imidation reaction shown below by heating, and is preferably represented by the following formula (2). Has a structure.

In the formula (2), A ₁ and A ₂ are the same as the respective definitions in the above formula (1).
In formula (2), X ₂ is a tetravalent organic group, and the structure thereof is not particularly limited. If a specific example is given, the structure of said Formula (X-1)-(X-46) will be mentioned.
In formula (2), Y ₂ is a divalent organic group, and its structure is not particularly limited. If a specific example is given, the structure of said formula (Y-1)-(Y-77) will be mentioned.
Polyamic acid of the present invention for the purpose of a higher pretilt angle, in the formula (2), the divalent organic group in which a part of Y ₂ has a side chain structure capable of expressing a pretilt angle of the (Y ₁ '). In that case, specific examples of Y ₁ ′ include structures represented by the above formulas [2-1] to [2-51].

It is preferable to introduce a diamine having a heteroatom-containing structure, a polycyclic aromatic structure, or a biphenyl skeleton into the polyamic acid because the afterimage due to the accumulation of DC voltage can be reduced by reducing the volume resistivity of the polyamic acid. . As Y ₂ for that purpose, Y-19, Y-23, Y-25, Y-26, Y-27, Y-30, Y-31, Y-32, Y-33, Y-34, Y-35 Y-36, Y-40, Y-41, Y-42, Y-44, Y-45, Y-49, Y-50, Y-51, Y-61, Y-76, or Y-77. More preferred is Y-31, Y-40, Y-76 or Y-77.
Further, by increasing the surface free energy of the polyamic acid, the phase separation between the polyamic acid ester and the polyamic acid is further promoted, and the surface of the liquid crystal alignment film obtained by coating and baking becomes smoother. It is preferable to introduce a diamine having an amino group, a hydroxyl group, an amide group, a ureido group, or a carboxyl group into the polyamic acid. As Y ₂ for that purpose, Y-19, Y-31, Y-40, Y-45, Y-76, or Y-77 is more preferable, and Y-76 or Y-77 having a carboxyl group is particularly preferable.

<Method for producing polyamic acid ester>
The polyamic acid ester represented by the above formula (1) is obtained by reaction of any of the tetracarboxylic acid derivatives represented by the following formulas (6) to (8) with the diamine compound represented by the formula (9). be able to.

（式中、Ｘ_１、Ｙ_１、Ｒ_１、Ａ_１及びＡ_２はそれぞれ上記式（１）中の定義と同じである。）
上記式（１）で表されるポリアミック酸エステルは、上記モノマーを用いて、以下に示す（１）〜（３）の方法で合成することができる。
（１）ポリアミック酸から合成する場合
ポリアミック酸エステルは、テトラカルボン酸二無水物とジアミンから得られるポリアミック酸をエステル化することによって合成することができる。

(In the formula, X ₁ , Y ₁ , R ₁ , A ₁ and A ₂ are the same as defined in the formula (1)).
The polyamic acid ester represented by the above formula (1) can be synthesized by the following methods (1) to (3) using the monomer.
(1) When synthesizing from polyamic acid The polyamic acid ester can be synthesized by esterifying a polyamic acid obtained from tetracarboxylic dianhydride and diamine.

Specifically, the polyamic acid and the esterifying agent are reacted in the presence of an organic solvent at −20 ° C. to 150 ° C., preferably 0 ° C. to 50 ° C., for 30 minutes to 24 hours, preferably 1 to 4 hours. Can be synthesized.
As the esterifying agent, those that can be easily removed by purification are preferred, and N, N-dimethylformamide dimethyl acetal, N, N-dimethylformamide diethyl acetal, N, N-dimethylformamide dipropyl acetal, N, N-dimethylformamide Dineopentyl butyl acetal, N, N-dimethylformamide di-t-butyl acetal, 1-methyl-3-p-tolyltriazene, 1-ethyl-3-p-tolyltriazene, 1-propyl-3-p -Tolyltriazene, 4- (4,6-dimethoxy-1,3,5-triazin-2-yl) -4-methylmorpholinium chloride and the like. The addition amount of the esterifying agent is preferably 2 to 6 molar equivalents per 1 mol of the polyamic acid repeating unit.

  The solvent used in the above reaction is preferably N, N-dimethylformamide, N-methyl-2-pyrrolidone, or γ-butyrolactone from the solubility of the polymer. These may be used alone or in combination. Also good. The concentration of the polymer at the time of synthesis is preferably 1 to 30% by mass, and more preferably 5 to 20% by mass from the viewpoint that polymer precipitation hardly occurs and a high molecular weight body is easily obtained.

(2) When synthesized by reaction of tetracarboxylic acid diester dichloride and diamine Polyamic acid ester can be synthesized from tetracarboxylic acid diester dichloride and diamine.

Specifically, tetracarboxylic acid diester dichloride and diamine in the presence of a base and an organic solvent are −20 ° C. to 150 ° C., preferably 0 ° C. to 50 ° C., 30 minutes to 24 hours, preferably 1 to 4 hours. It can be synthesized by reacting.
As the base, pyridine, triethylamine, 4-dimethylaminopyridine and the like can be used, but pyridine is preferable because the reaction proceeds gently. The amount of the base added is preferably 2 to 4 moles relative to the tetracarboxylic acid diester dichloride from the viewpoint that it can be easily removed and a high molecular weight product can be easily obtained.

  The solvent used in the above reaction is preferably N-methyl-2-pyrrolidone or γ-butyrolactone from the solubility of the monomer and polymer, and these may be used alone or in combination. The polymer concentration at the time of synthesis is preferably 1 to 30% by mass, and more preferably 5 to 20% by mass from the viewpoint that polymer precipitation hardly occurs and a high molecular weight body is easily obtained. In order to prevent hydrolysis of the tetracarboxylic acid diester dichloride, the solvent used for the synthesis of the polyamic acid ester is preferably dehydrated as much as possible, and it is preferable to prevent mixing of outside air in a nitrogen atmosphere.

(3) When a polyamic acid is synthesized from a tetracarboxylic acid diester and a diamine The polyamic acid ester can be synthesized by polycondensation of a tetracarboxylic acid diester and a diamine.

具体的には、テトラカルボン酸ジエステルとジアミンを縮合剤、塩基、有機溶剤の存在下で０℃〜１５０℃、好ましくは０℃〜１００℃において、３０分〜２４時間、好ましくは３〜１５時間反応させることによって合成することができる。

Specifically, tetracarboxylic acid diester and diamine in the presence of a condensing agent, a base and an organic solvent are 0 ° C. to 150 ° C., preferably 0 ° C. to 100 ° C., 30 minutes to 24 hours, preferably 3 to 15 hours. It can be synthesized by reacting.

Examples of the condensing agent include triphenyl phosphite, dicyclohexylcarbodiimide, 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride, N, N′-carbonyldiimidazole, dimethoxy-1,3,5-triazi Nylmethylmorpholinium, O- (benzotriazol-1-yl) -N, N, N ′, N′-tetramethyluronium tetrafluoroborate, O- (benzotriazol-1-yl) -N, N , N ′, N′-tetramethyluronium hexafluorophosphate, diphenyl (2,3-dihydro-2-thioxo-3-benzoxazolyl) phosphonate, and the like. It is preferable that the addition amount of a condensing agent is 2-3 times mole with respect to tetracarboxylic-acid diester.
As the base, tertiary amines such as pyridine and triethylamine can be used. The amount of the base added is preferably 2 to 4 times the molar amount of the diamine component from the viewpoint of easy removal and high molecular weight.

In the above reaction, the reaction proceeds efficiently by adding Lewis acid as an additive. As the Lewis acid, lithium halides such as lithium chloride and lithium bromide are preferable. The addition amount of the Lewis acid is preferably 0 to 1.0 times the mole of the diamine component.
Among the methods for synthesizing the three polyamic acid esters, since a high molecular weight polyamic acid ester is obtained, the synthesis method (1) or (2) is particularly preferable.
The polyamic acid ester solution obtained as described above can be polymerized by pouring into a poor solvent while stirring well. Precipitation is performed several times, and after washing with a poor solvent, a purified polyamic acid ester powder can be obtained at room temperature or by heating and drying. Although a poor solvent is not specifically limited, Water, methanol, ethanol, hexane, butyl cellosolve, acetone, toluene etc. are mentioned.

<Method for producing polyamic acid>
The polyamic acid represented by the above formula (2) can be obtained by a reaction between a tetracarboxylic dianhydride represented by the following formula (10) and a diamine compound represented by the formula (11).

Specifically, tetracarboxylic dianhydride and diamine are reacted in the presence of an organic solvent at −20 ° C. to 150 ° C., preferably 0 ° C. to 50 ° C. for 30 minutes to 24 hours, preferably 1 to 12 hours. Can be synthesized.
The organic solvent used in the above reaction is preferably N, N-dimethylformamide, N-methyl-2-pyrrolidone or γ-butyrolactone from the solubility of the monomer and polymer, and these are used alone or in combination of two or more. May be. The concentration of the polymer is preferably 1 to 30% by mass and more preferably 5 to 20% by mass from the viewpoint that the polymer is hardly precipitated and a high molecular weight body is easily obtained.
The polyamic acid obtained as described above can be recovered by precipitating the polymer by pouring into the poor solvent while thoroughly stirring the reaction solution. Moreover, the powder of polyamic acid refine | purified by performing precipitation several times, washing | cleaning with a poor solvent, and normal temperature or heat-drying can be obtained. Although a poor solvent is not specifically limited, Water, methanol, ethanol, hexane, butyl cellosolve, acetone, toluene etc. are mentioned.

<Liquid crystal aligning agent>
The liquid crystal aligning agent of the present invention contains the polyamic acid ester represented by the above formula (1) and the polyamic acid represented by the formula (2).
The weight average molecular weight of the polyamic acid ester and the weight average molecular weight of the polyamic acid are both preferably 5,000 to 300,000, and more preferably 10,000 to 200,000. The number average molecular weight is preferably 2,500 to 150,000, more preferably 5,000 to 10,000.

The content of the polyamic acid ester and the content of the polyamic acid in the liquid crystal aligning agent of the present invention is preferably 1/9 to 9/1 in terms of mass ratio of (polyamic acid ester / polyamic acid). The ratio is preferably 2/8 to 8/2, and particularly preferably 3/7 to 7/3. By setting the ratio within this range, it is possible to provide a liquid crystal aligning agent having good liquid crystal alignment properties and electrical characteristics.
The liquid crystal aligning agent of this invention is a form of the solution which said polyamic acid ester and polyamic acid melt | dissolved in the organic solvent. As long as it has such a form, for example, when a polyamic acid ester and / or polyamic acid is synthesized in an organic solvent, it may be the reaction solution obtained, or the reaction solution is diluted with an appropriate solvent. It may be a thing. When the polyamic acid ester and / or polyamic acid is obtained as a powder, it may be dissolved in an organic solvent to form a solution.

  The content (concentration) of the polyamic acid and polyamic acid ester (also referred to as a polymer in the present invention) in the liquid crystal aligning agent of the present invention can be appropriately changed depending on the thickness of the polyimide film to be formed. However, from the viewpoint of forming a uniform and defect-free coating film, the content of the polymer component is preferably 0.5% by mass or more with respect to the organic solvent, and 15% by mass from the viewpoint of storage stability of the solution. The following is preferable, and more preferably 1 to 10% by mass. In this case, a concentrated solution of the polymer may be prepared in advance, and diluted when such a concentrated solution is used as the liquid crystal alignment agent. The concentration of the concentrated solution of the polymer component is preferably 10 to 30% by mass, and more preferably 10 to 15% by mass. Alternatively, the polymer component powder may be heated when dissolved in an organic solvent to prepare a solution. The heating temperature is preferably 20 ° C to 150 ° C, particularly preferably 20 ° C to 80 ° C.

  The said organic solvent contained in the liquid crystal aligning agent of this invention will not be specifically limited if a polymer component melt | dissolves uniformly. Specific examples thereof include N, N-dimethylformamide, N, N-diethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-methylcaprolactam, Examples include 2-pyrrolidone, N-vinyl-2-pyrrolidone, dimethyl sulfoxide, dimethyl sulfone, γ-butyrolactone, 1,3-dimethyl-imidazolidinone, 3-methoxy-N, N-dimethylpropanamide and the like. You may use these 1 type or in mixture of 2 or more types. Moreover, even if it is a solvent which cannot melt | dissolve a polymer component uniformly by itself, if it is a range which a polymer does not precipitate, you may mix with said organic solvent.

  The liquid crystal aligning agent of this invention may contain the solvent for improving the coating-film uniformity at the time of apply | coating a liquid crystal aligning agent to a board | substrate other than the organic solvent for dissolving a polymer component. As such a solvent, a solvent having a surface tension lower than that of the organic solvent is generally used. Specific examples thereof include ethyl cellosolve, butyl cellosolve, butyl cellosolve acetate, ethyl carbitol, butyl carbitol, ethyl carbitol acetate, ethylene glycol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1- Butoxy-2-propanol, 1-phenoxy-2-propanol, propylene glycol monoacetate, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, di Propylene glycol, 2- (2-ethoxypropoxy) propanol, lactate methyl ester, lactate ethyl ester, lactate n-propyl ester, lactate n-butyl ester, lactic acid Isoamyl ester, and the like. Two types of these solvents may be used in combination.

  The liquid crystal aligning agent of this invention may contain various additives, such as a silane coupling agent and a crosslinking agent. The silane coupling agent is added for the purpose of improving the adhesion between the substrate on which the liquid crystal alignment agent is applied and the liquid crystal alignment film formed thereon. Although the specific example of a silane coupling agent is given to the following, it is not limited to this.

Specific examples of the silane coupling agent used in the present invention include 3-aminopropylmethyldiethoxysilane, 3-phenylaminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, (aminoethylaminomethyl) phenethyl triphenyl. Amines such as methoxysilane; Vinyls such as vinyltrimethoxysilane; 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidyl Epoxy systems such as Sidoxypropylmethyldimethoxysilane and 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane; (Meth) acrylic systems such as 3- (meth) acryloxypropylmethyldimethoxysilane; 3-ureidopropyl Ureido systems such as ethoxysilane; sulfide systems such as bis (3- (triethoxysilyl) propyl) disulfide; mercapto systems such as 3-mercaptopropylmethyldimethoxysilane; isocyanate systems such as 3-isocyanatopropyltriethoxysilane; triethoxy Aldehydes such as silylbutyraldehyde; and carbamates such as triethoxysilylpropylmethyl carbamate may be mentioned.
If the amount of the silane coupling agent added is too large, unreacted ones may adversely affect the liquid crystal orientation, and if too small, the effect on adhesion will not appear, so the amount of the silane coupling agent is 0 with respect to the solid content of the polymer. 0.01 to 5.0% by weight is preferable, and 0.1 to 1.0% by weight is more preferable.

When adding the said silane coupling agent, in order to prevent precipitation of a polymer, it is preferable to add before adding the solvent for improving the above-mentioned coating-film uniformity. Also, when adding a silane coupling agent, add it to the polyamic acid ester solution, the polyamic acid solution, or both the polyamic acid ester solution and the polyamic acid solution before mixing the polyamic acid ester solution and the polyamic acid solution. Can do. Moreover, it can add to a polyamic acid ester-polyamic acid mixed solution.
An imidization accelerator may be added to efficiently advance imidization of the polyamic acid ester when the coating film is baked. When adding an imidization accelerator, since imidation may advance by heating, it is preferable to add after diluting with a good solvent and / or a poor solvent.

<Liquid crystal alignment film>
The liquid crystal alignment film of the present invention is a film obtained by applying the liquid crystal aligning agent to a substrate, drying and baking. The substrate on which the liquid crystal aligning agent of the present invention is applied is not particularly limited as long as it is a highly transparent substrate, and a glass substrate, a silicon nitride substrate, an acrylic substrate, a polycarbonate substrate such as a polycarbonate substrate, or the like can be used. From the viewpoint of simplification of the process, it is preferable to use a substrate on which an ITO electrode or the like is formed. In the reflective liquid crystal display element, an opaque material such as a silicon wafer can be used as long as only one substrate is used. In this case, a material that reflects light, such as aluminum, can also be used.

  Examples of the method for applying the liquid crystal aligning agent of the present invention include a spin coating method, a printing method, and an ink jet method. Arbitrary temperature and time can be selected for the drying and baking steps after applying the liquid crystal aligning agent of the present invention. Usually, in order to sufficiently remove the organic solvent contained, the organic solvent is dried at 50 ° C. to 120 ° C. for 1 minute to 10 minutes, and then baked at 150 ° C. to 300 ° C. for 5 minutes to 120 minutes. Although the thickness of the coating film after baking is not specifically limited, Since the reliability of a liquid crystal display element may fall when too thin, it is 5-300 nm, Preferably it is 10-200 nm.

Examples of a method for aligning the obtained liquid crystal alignment film include a rubbing method and a photo-alignment processing method. The liquid crystal aligning agent of the present invention is particularly useful when used in the photo-alignment processing method.
As a specific example of the photo-alignment treatment method, there is a method in which the surface of the coating film is irradiated with radiation deflected in a certain direction, and in some cases, a heat treatment is further performed at a temperature of 150 to 250 ° C. to impart liquid crystal alignment ability. Can be mentioned. As the radiation, ultraviolet rays and / or visible rays having a wavelength of 100 nm to 800 nm can be used. Among these, ultraviolet rays having a wavelength of 100 nm to 400 nm are preferable, and those having a wavelength of 200 nm to 400 nm are particularly preferable. Moreover, in order to improve liquid crystal orientation, you may irradiate a radiation, heating a coating-film board | substrate at 50-250 degreeC. Dose of the radiation is preferably ^{1~10,000mJ / cm 2, 100~5,000mJ / cm} 2 is particularly preferred. The liquid crystal alignment film produced as described above can stably align liquid crystal molecules in a certain direction.

[Liquid crystal display element]
The liquid crystal display element of the present invention is a liquid crystal display element obtained by obtaining a substrate with a liquid crystal alignment film from the liquid crystal aligning agent of the present invention by the above-described method, performing an alignment treatment, and then preparing a liquid crystal cell by a known method. It is.
The method for producing the liquid crystal cell is not particularly limited. For example, a pair of substrates on which the liquid crystal alignment film is formed is preferably 1 to 30 μm, more preferably 2 to 10 μm with the liquid crystal alignment film surface inside. A method is generally employed in which the spacer is fixed with a sealing agent after the spacer is sandwiched, and liquid crystal is injected and sealed. The method for enclosing the liquid crystal is not particularly limited, and examples thereof include a vacuum method for injecting liquid crystal after reducing the pressure inside the produced liquid crystal cell, and a dropping method for sealing after dropping the liquid crystal.
The liquid crystal alignment film of the present invention has a liquid crystal layer between a pair of substrates provided with electrodes, and includes a polymerizable compound that is polymerized by at least one of active energy rays and heat between the pair of substrates. It is also preferably used for a liquid crystal display device produced through a step of polymerizing a polymerizable compound by arranging at least one of active energy rays and heating while applying a voltage between electrodes. Here, ultraviolet rays are suitable as the active energy ray.
The liquid crystal display element controls the pretilt of liquid crystal molecules by a PSA (Polymer Sustained Alignment) method. In the PSA method, a small amount of a photopolymerizable compound, for example, a photopolymerizable monomer is mixed in a liquid crystal material, and after assembling a liquid crystal cell, a predetermined voltage is applied to the liquid crystal layer and the photopolymerizable compound is irradiated with ultraviolet rays. The pretilt of the liquid crystal molecules is controlled by the produced polymer. Since the alignment state of the liquid crystal molecules when the polymer is formed is stored even after the voltage is removed, the pretilt of the liquid crystal molecules can be adjusted by controlling the electric field formed in the liquid crystal layer. The PSA method does not require a rubbing process and is suitable for forming a vertical alignment type liquid crystal layer in which it is difficult to control the pretilt by the rubbing process.
That is, in the liquid crystal display element of this embodiment, after obtaining the substrate with the liquid crystal alignment film from the liquid crystal alignment treatment agent of this embodiment by the above-described method, a liquid crystal cell is prepared, and at least one of irradiation with ultraviolet rays and heating is performed. The orientation of the liquid crystal molecules can be controlled by polymerizing the polymerizable compound.
To give an example of manufacturing a PSA type liquid crystal cell, a pair of substrates on which a liquid crystal alignment film is formed is prepared, spacers are dispersed on the liquid crystal alignment film of one substrate, and the liquid crystal alignment film surface is on the inside. Then, the other substrate is bonded and the liquid crystal is injected under reduced pressure, or the liquid crystal is dropped on the liquid crystal alignment film surface on which the spacers are dispersed, and then the substrate is bonded and sealed. Can be mentioned.
In the liquid crystal, a polymerizable compound that is polymerized by heat or ultraviolet irradiation is mixed. Examples of the polymerizable compound include compounds having at least one polymerizable unsaturated group such as an acrylate group or a methacrylate group in the molecule. In that case, it is preferable that a polymeric compound is 0.01-10 mass parts with respect to 100 mass parts of a liquid-crystal component, More preferably, it is 0.1-5 mass parts. When the polymerizable compound is less than 0.01 part by mass, the polymerizable compound is not polymerized and the orientation of the liquid crystal cannot be controlled, and when it exceeds 10 parts by mass, the amount of the unreacted polymerizable compound increases and the liquid crystal display element. The seizure characteristics of the steel deteriorate. After the liquid crystal cell is produced, the polymerizable compound is polymerized by irradiating heat or ultraviolet rays while applying an AC or DC voltage to the liquid crystal cell. Thereby, the alignment of the liquid crystal molecules can be controlled.
In addition, the liquid crystal aligning agent of the present invention has a liquid crystal layer between a pair of substrates provided with electrodes, and is polymerized by at least one of active energy rays and heat between the pair of substrates. It is also preferably used for a liquid crystal display device manufactured through a step of disposing a liquid crystal alignment film containing a group and applying a voltage between the electrodes. Here, ultraviolet rays are suitable as the active energy ray. In order to obtain a liquid crystal alignment film containing a polymerizable group that polymerizes from at least one of active energy rays and heat, a method of adding a compound containing this polymerizable group to a liquid crystal aligning agent, A method using a coalescing component may be mentioned.

Hereinafter, the present invention will be specifically described with reference to examples. However, it goes without saying that the present invention is not construed as being limited to these examples.
Hereinafter, the abbreviations of the compounds used in the examples and comparative examples, their structures, and methods for measuring each property are as follows.
1,3DM-CBDE-Cl: dimethyl 1,3-bis (chlorocarbonyl) -1,3-dimethylcyclobutane-2,4-dicarboxylate CBDE: 2,4-bis (methoxycarbonyl) cyclobutane-1, 3-dicarboxylic acid BODE: 3,6-bis (methoxycarbonyl) octahydropentalene-1,4-dicarboxylic acid DMT-MM: 4- (4,6-dimethoxy-1,3,5-triazine-2 -Yl) -4-methylmorpholinium chloride NMP: N-methyl-2-pyrrolidone BCS: butyl cellosolve γ-BL: γ-butyrolactone BCA: butyl cellosolve acetate

[viscosity]
In the synthesis example, the viscosity of the polyamic acid ester and the polyamic acid solution is an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.). ), Measured at a temperature of 25 ° C.
[Molecular weight]
The molecular weight of the polyamic acid ester is measured by a GPC (room temperature gel permeation chromatography) apparatus, and is a number average molecular weight (hereinafter also referred to as Mn) and a weight average molecular weight (hereinafter also referred to as Mw) in terms of polyethylene glycol and polyethylene oxide. Was calculated.
GPC device: manufactured by Shodex (GPC-101)
Column: manufactured by Shodex (series of KD803 and KD805)
-Column temperature: 50 ° C
Eluent: N, N-dimethylformamide (as an additive, lithium bromide-hydrate (LiBr · H ₂ O) is 30 mmol / L, phosphoric acid / anhydrous crystal (o-phosphoric acid) is 30 mmol / L, Tetrahydrofuran (THF) 10ml / L)
-Flow rate: 1.0 ml / min-Standard sample for preparing a calibration curve: TSK standard polyethylene oxide (weight average molecular weight (Mw) of about 900,000, 150,000, 100,000, 30,000) manufactured by Tosoh Corporation, and Polyethylene glycol manufactured by Polymer Laboratory (peak top molecular weight (Mp) of about 12,000, 4,000, 1,000). In order to avoid the overlapping of peaks, the measurement was performed by mixing four types of 900,000, 100,000, 12,000, and 1,000, and three types of 150,000, 30,000, and 4,000. Two samples of mixed samples are measured separately.

[Pretilt angle measurement]
The pretilt angle was measured using a Mueller matrix polarimeter (Axometrics, trade name: AxoScan) after heating the liquid crystal cell at 110 ° C. for 30 minutes.
[Evaluation of residual DC]
Evaluation of the charge storage characteristics was performed immediately after a DC wave of 1 V was applied to a liquid crystal cell at a temperature of 23 ° C., superimposed with a direct current of 1 V and driven for 90 hours, and then the direct current was turned off. The residual voltage remaining in the liquid crystal cell was measured by an optical flicker elimination method. When the residual voltage was 0.4 V or less, it was evaluated as good, and when it was 0.4 V or more, it was evaluated as defective.

(Synthesis Example 1)
Synthesis of dimethyl-1,3-bis (chlorocarbonyl) -1,3-dimethylcyclobutane-2,4-dicarboxylate (1,3DMCBDE-Cl) (a-1) Synthesis of tetracarboxylic acid dialkyl ester

窒素気流下中、３Ｌの四つ口フラスコに、１，３−ジメチルシクロブタン−１，２，３，４−テトラカルボン酸二無水物（式（５−１）の化合物、以下１，３−ＤＭ−ＣＢＤＡと略す）を２２０ｇ（０．９８１ｍｏｌ）と、メタノールを２２００ｇ（６．８７ｍｏｌ、１，３−ＤＭ−ＣＢＤＡに対して１０ｗｔ倍）仕込み、６５℃にて加熱還流を行ったところ、３０分で均一な溶液となった。反応溶液はそのまま４時間３０分加熱還流下で撹拌した。この反応液を高速液体クロマトグラフィー（以下、ＨＰＬＣと略す）にて測定した。この測定結果の解析は後述する。

Under a nitrogen stream, a 3-L four-necked flask was charged with 1,3-dimethylcyclobutane-1,2,3,4-tetracarboxylic dianhydride (compound of formula (5-1), hereinafter referred to as 1,3-DM. -CBDA) 220 g (0.981 mol) and methanol 2200 g (6.87 mol, 10 wt times relative to 1,3-DM-CBDA) were charged and refluxed at 65 ° C. for 30 minutes. A homogeneous solution was obtained. The reaction solution was stirred for 4 hours and 30 minutes under heating and reflux. This reaction solution was measured by high performance liquid chromatography (hereinafter abbreviated as HPLC). The analysis of the measurement result will be described later.

After evaporating the solvent from the reaction solution with an evaporator, 1301 g of ethyl acetate was added, heated to 80 ° C., and refluxed for 30 minutes. Then, it cooled until the internal temperature became 25 degreeC at the speed | rate of 2-3 degreeC in 10 minutes, and stirred for 30 minutes as it was at 25 degreeC. The precipitated white crystals were taken out by filtration, washed twice with 141 g of ethyl acetate, and then dried under reduced pressure to obtain 103.97 g of white crystals.
This crystal was confirmed to be compound (1-1) from the results of 1H NMR analysis and X-ray crystal structure analysis (HPLC relative area 97.5%) (yield 36.8%).
1H NMR (DMSO-d6, δppm); 12.82 (s, 2H), 3.60 (s, 6H), 3.39 (s, 2H), 1.40 (s, 6H).

(A-2) Synthesis of 1,3-DM-CBDE-C1

窒素気流下中、３Ｌの四つ口フラスコに、化合物（１−１）２３４．１５ｇ（０．８１ｍｏｌ）、ｎ−ヘプタン１１７０．７７ｇ（１１．６８ｍｏｌ．５ｗｔ倍）を仕込んだ後、ピリジン０．６４ｇ（０．０１ｍｏｌ）を加え、マグネチックスターラー攪拌下にて７５℃まで加熱撹拌した。続いて、塩化チオニル２８９．９３ｇ（１１．６８ｍｏｌ）を１時間かけて滴下した。滴下直後から発泡が開始し、滴下終了３０分後に反応溶液は均一となり、発泡は停止した。続いてそのまま７５℃にて１時間３０分撹拌した後、エバポレーターにて水浴４０℃で内容量が９２４．４２ｇになるまで溶媒を留去した。これを６０℃に加熱し、溶媒留去時に析出した結晶を溶解させ、６０℃にて熱時ろ過を行うことで不溶物をろ過した後、ろ液を２５℃まで１０分間に１℃の速度で冷却した。そのまま２５℃で３０分撹拌させた後、析出した白色結晶をろ過により取り出し、この結晶をｎ−ヘプタン２６４．２１ｇにて洗浄した。これを減圧乾燥することで、白色結晶を２２６．０９ｇ得た。
続いて窒素気流下中、３Ｌの四つ口フラスコに、上記で得られた白色結晶２２６．０９ｇ、ｎ−ヘプタン４５２．１８ｇを仕込んだ後、６０℃に加熱撹拌して結晶を溶解させた。その後、２５℃まで１０分間に１℃の速度で冷却撹拌し、結晶を析出させた。そのまま２５℃で１時間撹拌させた後、析出した白色結晶をろ過により取り出し、この結晶をｎ−ヘキサン１１３．０４ｇにて洗浄した後、減圧乾燥することで白色結晶を２０３．９１ｇ得た。この結晶は、１Ｈ ＮＭＲ分析結果により、化合物（３−１）すなわち、ジメチル−１，３−ビス（クロロカルボニル）−１，３−ジメチルシクロブタン−２，４−ジカルボキシレート（以下、１，３−ＤＭ−ＣＢＤＥ−Ｃ１という。）であるであることを確認した（ＨＰＬＣ相対面積９９．５％）（収率７７．２％）。
1H NMR (CDCl₃, δppm) : 3.78 (s,6H), 3.72 (s,2H), 1.69 (s,6H).

In a nitrogen stream, after charging 234.15 g (0.81 mol) of compound (1-1) and 117.77 g (11.68 mol.5 wt times) of n-heptane in a 3 L four-necked flask, the pyridine was mixed with 0.1. 64 g (0.01 mol) was added, and the mixture was heated and stirred to 75 ° C. while stirring with a magnetic stirrer. Subsequently, 289.93 g (11.68 mol) of thionyl chloride was added dropwise over 1 hour. Foaming started immediately after the dropping, and the reaction solution became uniform 30 minutes after the completion of the dropping, and the foaming stopped. Subsequently, the mixture was stirred as it was at 75 ° C. for 1 hour and 30 minutes, and then the solvent was distilled off with an evaporator until the internal volume reached 924.42 g in a water bath at 40 ° C. This was heated to 60 ° C., the crystals precipitated when the solvent was distilled off were dissolved, the insoluble matter was filtered by performing hot filtration at 60 ° C., and then the filtrate was heated to 25 ° C. at a rate of 1 ° C. for 10 minutes. It was cooled with. After stirring as it was at 25 ° C. for 30 minutes, the precipitated white crystal was taken out by filtration, and this crystal was washed with 264.21 g of n-heptane. This was dried under reduced pressure to obtain 226.09 g of white crystals.
Subsequently, 226.09 g of the white crystals obtained above and 454.18 g of n-heptane were charged into a 3 L four-necked flask in a nitrogen stream, and heated and stirred at 60 ° C. to dissolve the crystals. Thereafter, the mixture was cooled and stirred at a rate of 1 ° C. for 10 minutes to 25 ° C. to precipitate crystals. After stirring as it was at 25 ° C. for 1 hour, the precipitated white crystals were taken out by filtration, washed with 113.04 g of n-hexane, and then dried under reduced pressure to obtain 203.91 g of white crystals. According to the result of 1H NMR analysis, this crystal was found to be compound (3-1), that is, dimethyl-1,3-bis (chlorocarbonyl) -1,3-dimethylcyclobutane-2,4-dicarboxylate (hereinafter referred to as 1,3). -DM-CBDE-C1.) (HPLC relative area 99.5%) (yield 77.2%).
1H NMR (CDCl ₃ , δppm): 3.78 (s, 6H), 3.72 (s, 2H), 1.69 (s, 6H).

(Synthesis Example 2)
In a 100 ml four-necked flask containing a stir bar, 2.4707 g (9.50 mmol) of CBDE was taken, 64.22 g of NMP was added, and dissolved by stirring. Subsequently, 0.5126 g (5.00 mmol) of triethylamine, 1.6042 g (8.01 mmol) of 4,4′-diaminodiphenyl ether, and 0.7579 g of 1-octadecanoxy-2,4-diaminobenzene ( 2.01 mmol) and stirred to dissolve. While stirring this solution, 8.45 g (30.5 mmol) of DMT-MM (15 ± 2 wt% hydrate) was added, and 11.79 g of NMP was further added, followed by stirring at room temperature for 18 hours. A solution was obtained. The viscosity of this polyamic acid ester solution at a temperature of 25 ° C. was 17.75 mPa · s. This polyamic acid ester solution was poured into 490 g of methanol while stirring, and the deposited precipitate was collected by filtration, then washed with 178 g of methanol five times and dried to obtain 3.70 g of polyamic acid ester resin powder. Obtained. The molecular weight of this polyamic acid ester was Mn = 13,573 and Mw = 30,201.
Take 1.4040 g of the polyamic acid ester resin powder obtained in a 50 ml sample tube containing a stir bar, add 11.7663 g of NMP, stir at room temperature for 24 hours to dissolve, and prepare a polyamic acid ester solution (PAE-1). Obtained.

(Synthesis Example 3)
In a 100 ml four-necked flask containing a stir bar, 2.4790 g (9.53 mmol) of CBDE was taken, 64.08 g of NMP was added, and stirred to dissolve. Subsequently, 0.505 g (4.99 mmol) of triethylamine, 1.5883 g (8.01 mmol) of 4,4′-diaminodiphenylmethane, and 0.7691 g (2.02 mmol) of DA-1 were added and dissolved by stirring. I let you. While stirring this solution, 8.37 g (30.2 mmol) of DMT-MM (15 ± 2% by weight hydrate) was added, and 11.47 g of NMP was further added, followed by stirring at room temperature for 18 hours. A solution was obtained. The viscosity of this polyamic acid ester solution at a temperature of 25 ° C. was 9.77 mPa · s. This polyamic acid ester solution was poured into 490 g of methanol while stirring, and the deposited precipitate was collected by filtration, then washed with 178 g of methanol five times and dried to obtain 3.71 g of polyamic acid ester resin powder. Obtained. The molecular weight of this polyamic acid ester was Mn = 12,046 and Mw = 25,408.
Take 1.2639 g of the resulting polyamic acid ester resin powder in a 50 ml sample tube containing a stir bar, add 11.3761 g of NMP, and stir at room temperature for 24 hours to dissolve, to obtain a polyamic acid ester solution (PAE-2) Obtained.

(Synthesis Example 4)
In a 100 ml four-necked flask containing a stir bar, 2.4715 g (9.50 mmol) of CBDE was taken, 64.78 g of NMP was added, and the mixture was stirred to dissolve. Subsequently, 0.511 g (5.05 mmol) of triethylamine, 1.5832 g (8.01 mmol) of 4,4′-diaminodiphenylmethane, and 0.8169 g (2.00 mmol) of DA-2 were added and dissolved by stirring. I let you. While stirring this solution, 8.33 g (30.1 mmol) of DMT-MM (15 ± 2 wt% hydrate) was added, and 11.07 g of NMP was further added, followed by stirring at room temperature for 18 hours. A solution was obtained. The viscosity of this polyamic acid ester solution at a temperature of 25 ° C. was 11.92 mPa · s. This polyamic acid ester solution was added to 495 g of methanol while stirring, and the deposited precipitate was collected by filtration, then washed with 180 g of methanol five times and dried to obtain 3.64 g of polyamic acid ester resin powder. Obtained. The molecular weight of this polyamic acid ester was Mn = 10,926 and Mw = 23,652.
Take 0.9682 g of the polyamic acid ester resin powder obtained in a 50 ml sample tube containing a stir bar, add 8.723 g of NMP, and stir at room temperature for 24 hours to dissolve, to obtain a polyamic acid ester solution (PAE-3). Obtained.

(Synthesis Example 5)
A 300 mL four-necked flask equipped with a stirrer was placed in a nitrogen atmosphere, 1.5123 g (14.0 mmol) of m-phenylenediamine and 1.0387 g (2.45 mmol) of DA-3, 121.76 g of NMP as a base 2.91 g (36.8 mmol) of pyridine was added and dissolved by stirring. Next, 4.9904 g (15.3 mmol) of 1,3DM-CBDE-Cl was added while stirring the diamine solution, and the mixture was reacted for 4 hours under water cooling. The obtained polyamic acid ester solution was poured into 641 g of water while stirring, and the precipitated white precipitate was collected by filtration, and then once with 641 g of water, once with 641 g of ethanol, and 130 g of ethanol. 4.39 g of polyamic acid ester resin powder was obtained by washing 3 times and drying. The molecular weight of this polyamic acid ester was Mn = 6,757 and Mw = 13,415.
Take 2.0738 g of the obtained polyamic acid ester resin powder in a 50 ml sample tube containing a stir bar, add 28.696 g of NMP, and stir at room temperature for 24 hours to dissolve, to obtain a polyamic acid ester solution (PAE-4). Obtained.

(Synthesis Example 6)
A 300 mL four-necked flask equipped with a stirrer is placed in a nitrogen atmosphere, 3.488 g (13.5 mmol) of DA-8 and 0.8571 g (2.39 mmol) of DA-4, 154.59 g of NMP, and pyridine as a base. 2.84 g (15.0 mmol) was added and dissolved by stirring. Next, while stirring this diamine solution, 4.8709 g (36.0 mmol) of 1,3DM-CBDE-Cl was added and reacted for 4 hours under water cooling. The obtained polyamic acid ester solution was poured into 814 g of water while stirring, and the precipitated white precipitate was collected by filtration, and then once with 814 g of water, once with 814 g of ethanol, and 207 g of ethanol. 7.46 g of polyamic acid ester resin powder was obtained by washing 3 times and drying. The molecular weight of this polyamic acid ester was Mn = 17,559 and Mw = 45,602.
Take 1.2935 g of the polyamic acid ester resin powder obtained in a 50 ml sample tube containing a stir bar, add 11.6417 g of NMP, stir at room temperature for 24 hours to dissolve, and prepare a polyamic acid ester solution (PAE-5). Obtained.

(Synthesis Example 7)
In a 100 ml four-necked flask containing a stirring bar, 2.4717 g (9.50 mmol) of CBDE was taken, 61.43 g of NMP was added, and the mixture was stirred to dissolve. Subsequently, 0.5077 g (5.02 mmol) of triethylamine, 1.5866 g (8.00 mmol) of 4,4′-diaminodiphenylmethane, and 0.8627 g (1.99 mmol) of DA-5 were added and dissolved by stirring. I let you. While stirring this solution, 8.30 g (30.0 mmol) of DMT-MM (15 ± 2 wt% hydrate) was added, and 11.71 g of NMP was further added, followed by stirring at room temperature for 18 hours. A solution was obtained. The viscosity of this polyamic acid ester solution at a temperature of 25 ° C. was 12.64 mPa · s. This polyamic acid ester solution was added to 500 g of methanol while stirring, and the deposited precipitate was collected by filtration, then washed with 180 g of methanol five times and dried to obtain 3.95 g of polyamic acid ester resin powder. Obtained. The molecular weight of this polyamic acid ester was Mn = 10,737 and Mw = 23,149.
Take 1.62 g of the polyamic acid ester resin powder obtained in a 50 ml sample tube containing a stir bar, add 14.5822 g of NMP, stir at room temperature for 24 hours to dissolve, and prepare a polyamic acid ester solution (PAE-6). Obtained.

(Synthesis Example 8)
In a 100 ml four-necked flask containing a stir bar, 2.3591 g (7.51 mmol) of BODE and 0.6525 g (2.51 mmol) of CBDE were added, and 32 g of NMP was added and dissolved by stirring. Subsequently, 0.53 g (5.24 mmol) of triethylamine, 0.9194 g (8.50 mmol) of p-phenylenediamine, and 0.695 g (1.50 mmol) of DA-6 were added and dissolved by stirring. While stirring this solution, 8.176 g (30.1 mmol) of DMT-MM (15 ± 2% by weight hydrate) was added, and 10.1 g of NMP was further added, and the mixture was stirred at room temperature for 18 hours. A solution was obtained. The viscosity of this polyamic acid ester solution at a temperature of 25 ° C. was 15.0 mPa · s. This polyamic acid ester solution was added to 330 g of methanol while stirring, the deposited precipitate was collected by filtration, subsequently washed with 110 g of methanol five times, and dried to obtain 3.60 g of polyamic acid ester resin powder. Obtained. The molecular weight of this polyamic acid ester was Mn = 6,757 and Mw = 13,415.
Take 1.75885 g of the polyamic acid ester resin powder obtained in a 50 ml sample tube containing a stir bar, add 16.253 g of NMP, stir at room temperature for 24 hours to dissolve, and prepare a polyamic acid ester solution (PAE-7). Obtained.

(Synthesis Example 9)
In a 100 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, 1.8258 g (16.9 mmol) of p-phenylenediamine and 1.5253 g (3.00 mmol) of D-7 were added, and 35.6 g of NMP was added. The mixture was stirred and dissolved while feeding nitrogen. While stirring the diamine solution, 4.4822 g (20.0 mmol) of 2.3.5-tricarboxycyclopentylacetic acid dianhydride was added, and NMP was further added so that the solid content concentration was 15% by weight. The solution was stirred for 24 hours to obtain a solution of polyamic acid (PAA-1). The viscosity of this polyamic acid solution at a temperature of 25 ° C. was 167 mPa · s. Moreover, the molecular weight of this polyamic acid was Mn = 16,223 and Mw = 47,846.

(Synthesis Example 10)
20.50 g of the polyamic acid (PAA-1) solution obtained in Synthesis Example 9 was taken in a 50 ml eggplant-shaped flask containing a stir bar, and 13.55 g of NMP was added and stirred. To this solution, 3.87 g (25.9 mmol) of 1-methyl-3-p-tolyltriazene was added and stirred at room temperature for 4 hours. After 4 hours, the reaction solution was added to 340 g of methanol while stirring, and the deposited precipitate was collected by filtration, subsequently washed 5 times with 110 g of methanol, and dried to obtain 2. a polyamic acid ester resin powder. 44 g was obtained. The molecular weight of this polyamic acid ester was Mn = 9,206 and Mw = 28,883.
Take 1.5485 g of the polyamic acid ester resin powder obtained in a 50 ml sample tube containing a stirring bar, add 13.9603 g of NMP, stir at room temperature for 24 hours to dissolve, and prepare a polyamic acid ester solution (PAE-8). Obtained.

(Synthesis Example 11)
A 300 mL four-necked flask equipped with a stirrer was placed in a nitrogen atmosphere, 2.4071 g (12.1 mmol) of 4,4′-diaminodiphenylmethane and 1.0871 g (2.15 mmol) of DA-7 were added, and 130.3 g of NMP was added. Then, 2.54 g (32.1 mmol) of pyridine as a base was added and dissolved by stirring. Next, while stirring the diamine solution, 4.3526 g (13.4 mmol) of 1,3DM-CBDE-Cl was added and reacted for 4 hours under water cooling. The obtained polyamic acid ester solution was poured into 686 g of water with stirring, and the precipitated white precipitate was collected by filtration, followed by once with 686 g of water, once with 686 g of ethanol, and 170 g of ethanol. By washing three times and drying, 4.58 g of polyamic acid ester resin powder was obtained. The molecular weight of this polyamic acid ester was Mn = 9,233 and Mw = 20,108.
Take 1.5485 g of the polyamic acid ester resin powder obtained in a 50 ml sample tube containing a stirring bar, add 13.9603 g of NMP, and stir at room temperature for 24 hours to dissolve, to obtain a polyamic acid ester solution (PAE-9). Obtained.

(Synthesis Example 12)
Into a 100 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube was added 1.848 g (9.23 mmol) of 4,4′-diaminodiphenyl ether and 2.1025 g (13.82 mmol) of 3,5-diaminobenzoic acid. 39.7 g of NMP was added, and dissolved by stirring while feeding nitrogen. While stirring this diamine solution, 4.8162 g (22.08 mmol) of pyromellitic dianhydride was added, NMP was further added so that the solid content concentration was 15% by weight, and the mixture was stirred at room temperature for 24 hours to polyamic acid. A solution of (PAA-2) was obtained. The viscosity of this polyamic acid solution at a temperature of 25 ° C. was 257 mPa · s. Moreover, the molecular weight of this polyamic acid was Mn = 13,620 and Mw = 28,299.

(Synthesis Example 13)
In a 100 mL four-necked flask equipped with a stirrer and a nitrogen introduction tube, 7.9663 g (40 mmol) of 4,4′-diaminodiphenylamine was added, 31.7 g of NMP was added, and the mixture was stirred and dissolved while feeding nitrogen. While stirring this diamine solution, 7.1339 g (36.01 mmol) of 1,2,3,4-butanetetracarboxylic dianhydride was added, and NMP was further added so that the solid content concentration was 25% by weight. The mixture was stirred at room temperature for 24 hours to obtain a polyamic acid (PAA-3) solution. The viscosity of this polyamic acid solution at a temperature of 25 ° C. was 2680 mPa · s. Moreover, the molecular weight of this polyamic acid was Mn = 8,176 and Mw = 16,834.

(Synthesis Example 14)
In a 100 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, 1.5987 g (8.02 mmol) of 4,4′-diaminodiphenylamine and 1.8304 g (12.03 mmol) of 3,5-diaminobenzoic acid were placed. , 56.7 g of NMP was added and stirred and dissolved while feeding nitrogen. While stirring the diamine solution, 3.7675 g (19.21 mmol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride was added, and NMP was further added so that the solid content concentration was 15% by mass. The mixture was stirred at room temperature for 24 hours to obtain a polyamic acid (PAA-4) solution. The viscosity of this polyamic acid solution at a temperature of 25 ° C. was 368 mPa · s. Moreover, the molecular weight of this polyamic acid was Mn = 15,117 and Mw = 34,638.

(Synthesis Example 15)
2.100 g (10.04 mmol) of 2,2′-dimethyl-4,4′-diaminobiphenyl was taken into a 100 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, and 29.6 g of NMP was added thereto. The solution was stirred and dissolved while feeding. While stirring this diamine solution, 0.902 g (4.60 mmol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride and 1.0905 g (5.00 mmol) of pyromellitic dianhydride were added, Further, NMP was added so that the solid content concentration was 10% by weight, and the mixture was stirred at room temperature for 24 hours to obtain a polyamic acid (PAA-5) solution. The viscosity of this polyamic acid solution at a temperature of 25 ° C. was 585.7 mPa · s. Moreover, the molecular weight of this polyamic acid was Mn = 13,936 and Mw = 37,376.

(Synthesis Example 16)
In a 100 mL four-necked flask with a stirrer and a nitrogen inlet tube, 1.9217 g (9.60 mmol) of 4,4′-diaminodiphenyl ether and 0.9028 g of 1-octadecanoxy-2,4-diaminobenzene (2.40 mmol) was taken, 36.62 g of NMP was added, and the mixture was stirred and dissolved while feeding nitrogen. While stirring the diamine solution, 2.3088 g (11.8 mmol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride was added, and NMP was further added so that the solid concentration was 10% by weight. The mixture was stirred at room temperature for 24 hours to obtain a solution of polyamic acid (PAA-6). The viscosity of this polyamic acid solution at a temperature of 25 ° C. was 115.6 mPa · s. Moreover, the molecular weight of this polyamic acid was Mn = 18,794 and Mw = 53,139.

(Synthesis Example 17)
In a 100 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, 1.986 g (9.63 mmol) of 4,4′-diaminodiphenylmethane and 0.9125 g (2.40 mmol) of DA-1 were taken, and 36 NMP was added. .59 g was added and dissolved by stirring while feeding nitrogen. While stirring the diamine solution, 2.3059 g (11.8 mmol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride was added, and NMP was further added so that the solid concentration was 10% by weight. The solution was stirred at room temperature for 24 hours to obtain a polyamic acid (PAA-7) solution. The viscosity of this polyamic acid solution at a temperature of 25 ° C. was 49.2 mPa · s. Moreover, the molecular weight of this polyamic acid was Mn = 14,544 and Mw = 37,862.

(Synthesis Example 18)
In a 100 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, 1.902 g (9.59 mmol) of 4,4′-diaminodiphenylmethane and 0.9833 g (2.41 mmol) of DA-2 were taken, and 36 NMP was added. .59 g was added and dissolved by stirring while feeding nitrogen. While stirring the diamine solution, 2.3137 g (11.8 mmol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride was added, and NMP was further added so that the solid content concentration was 10% by weight. The solution was stirred at room temperature for 24 hours to obtain a polyamic acid (PAA-8) solution. The viscosity of this polyamic acid solution at a temperature of 25 ° C. was 61.1 mPa · s. Moreover, the molecular weight of this polyamic acid was Mn = 15,110 and Mw = 40,878.

(Synthesis Example 19)
In a 50 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, 1.6494 g (15.3 mmol) of m-phenylenediamine and 1.1508 g (2.71 mmol) of DA-3 were added, and 30.8 g of NMP was added. The mixture was stirred and dissolved while feeding nitrogen. While stirring this diamine solution, 3.995 g (17.8 mmol) of 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride was added, and the solid content concentration became 15% by weight. NMP was added as described above and stirred at room temperature for 24 hours to obtain a solution of polyamic acid (PAA-9). The viscosity of this polyamic acid solution at a temperature of 25 ° C. was 80 mPa · s. Moreover, the molecular weight of this polyamic acid was Mn = 9,546 and Mw = 20,553.

(Synthesis Example 20)
To a 50 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, 3.294 g (12.8 mmol) of DA-8 and 0.8098 g (2.26 mmol) of DA-4 were taken, and 33.7 g of NMP was added. The solution was stirred and dissolved while feeding nitrogen. While stirring the diamine solution, 3.3297 g (14.9 mmol) of 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride was added, and the solid content concentration was further 15% by weight. NMP was added and stirred at room temperature for 24 hours to obtain a polyamic acid (PAA-10) solution. The viscosity of this polyamic acid solution at a temperature of 25 ° C. was 332.5 mPa · s. Moreover, the molecular weight of this polyamic acid was Mn = 17,058 and Mw = 39,0162.

(Synthesis Example 21)
In a 100 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, 1.9044 g (9.61 mmol) of 4,4′-diaminodiphenylmethane and 1.0487 g (2.41 mmol) of DA-5 were taken, and 37 mg of NMP was added. .49 g was added and dissolved by stirring while feeding nitrogen. While stirring the diamine solution, 2.3123 g (11.8 mmol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride was added, and NMP was further added so that the solid content concentration was 10% by weight. The mixture was stirred at room temperature for 24 hours to obtain a polyamic acid (PAA-11) solution. The viscosity of this polyamic acid solution at a temperature of 25 ° C. was 47 mPa · s. Moreover, the molecular weight of this polyamic acid was Mn = 7,520 and Mw = 15,403.

(Synthesis Example 22)
In a 50 mL four-necked flask equipped with a stirrer and a nitrogen introduction tube, 5.03 g (20.1 mmol) of octahydropentalene-1,3,4,6-tetracarboxylic dianhydride and p-phenylenediamine were added. 2.03 g (18.8 mmol) and 3.73 g (8.05 mmol) of DA-6 were added, 23.0 g of NMP was added and reacted at 40 ° C. for 5 hours, and then 1, 2, 3, 4 -1.28 g (6.53 mmol) of cyclobutanetetracarboxylic acid and 24.5 g of NMP were added and reacted at 40 ° C. for 6 hours to obtain a solution of polyamic acid (PAA-12). The molecular weight of this polyamic acid was Mn: 12,900 and Mw: 31,500.

(Synthesis Example 23)
In a 50 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, 2.526 g (12.7 mmol) of 4,4′-diaminodiphenylmethane and 1.1413 g (2.25 mmol) of DA-7 were taken, and NMP 31 .8 g was added and dissolved by stirring while feeding nitrogen. While stirring the diamine solution, 3.3266 g (14.8 mmol) of 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride was added, and the solid content concentration became 15% by weight. NMP was added and stirred at room temperature for 24 hours to obtain a solution of polyamic acid (PAA-13). The viscosity of this polyamic acid solution at a temperature of 25 ° C. was 111.6 mPa · s. Moreover, the molecular weight of this polyamic acid was Mn = 10,050 and Mw = 22,2353.

Example 1
In a 20 ml sample tube containing a stir bar, 1.4441 g of the polyamic acid ester solution (PAE-1) obtained in Synthesis Example 2 and 2.2827 g of the polyamic acid solution (PAA-2) obtained in Synthesis Example 12 were used. Then, 2.6117 g of NMP and 1.636 g of BCS were added and stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal aligning agent (A-1).

(Example 2)
In a 20 ml sample tube containing a stirrer, 1.4471 g of the polyamic acid ester solution (PAE-2) obtained in Synthesis Example 3 and 1.1812 g of the polyamic acid solution (PAA-3) obtained in Synthesis Example 13 were used. Then, 3.8092 g of NMP and 1.6005 g of BCS were added and stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal aligning agent (A-2).

(Example 3)
In a 20 ml sample tube containing a stir bar, 1.4544 g of the polyamic acid ester solution (PAE-3) obtained in Synthesis Example 4 and 2.1419 g of the polyamic acid solution (PAA-4) obtained in Synthesis Example 14 were used. Then, 2.8338 g of NMP and 1.6377 g of BCS were added and stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal aligning agent (A-3).

Example 4
In a 20 ml sample tube containing a stir bar, 1.4469 g of the polyamic acid ester solution (PAE-4) obtained in Synthesis Example 5 and 3.3168 g of the polyamic acid solution (PAA-5) obtained in Synthesis Example 15 were used. Then, 1.6505 g of NMP and 1.5985 g of BCS were added and stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal aligning agent (A-4).

(Example 5)
In a 20 ml sample tube containing a stir bar, 1.4491 g of the polyamic acid ester solution (PAE-5) obtained in Synthesis Example 6 and 1.1563 g of the polyamic acid solution (PAA-3) obtained in Synthesis Example 13 were used. Then, 3.8169 g of NMP and 1.6107 g of BCS were added and stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal aligning agent (A-5).

(Example 6)
In a 20 ml sample tube containing a stirring bar, 1.4613 g of the polyamic acid ester solution (PAE-6) obtained in Synthesis Example 7 and 1.1505 g of the polyamic acid solution (PAA-3) obtained in Synthesis Example 13 were used. Then, 3.8275 g of NMP and 1.6049 g of BCS were added and stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal aligning agent (A-6).

(Example 7)
In a 20 ml sample tube containing a stir bar, 1.4575 g of the polyamic acid ester solution (PAE-7) obtained in Synthesis Example 8 and 2.285 g of the polyamic acid solution (PAA-2) obtained in Synthesis Example 12 were used. Then, 2.6783 g of NMP and 1.6070 g of BCS were added and stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal aligning agent (A-7).

(Example 8)
In a 20 ml sample tube containing a stir bar, 1.4474 g of the polyamic acid ester solution (PAE-8) obtained in Synthesis Example 10 and 3.3261 g of the polyamic acid solution (PAA-5) obtained in Synthesis Example 15 were used. Then, 1.6521 g of NMP and 1.6016 g of BCS were added and stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal aligning agent (A-8).

Example 9
In a 20 ml sample tube containing a stirring bar, 1.4553 g of the polyamic acid ester solution (PAE-9) obtained in Synthesis Example 11 and 2.1457 g of the polyamic acid solution (PAA-4) obtained in Synthesis Example 14 were used. Then, 2.8221 g of NMP and 1.6070 g of BCS were added and stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal aligning agent (A-9).

(Comparative Example 1)
In a 20-ml sample tube containing a stir bar, 1.4888 g of the polyamic acid solution (PAA-6) obtained in Synthesis Example 16 and 2.2959 g of the polyamic acid solution (PAA-2) obtained in Synthesis Example 12 were taken. Then, 2.7135 g of NMP and 1.6059 g of BCS were added and stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal aligning agent (B-1).

(Comparative Example 2)
In a 20 ml sample tube containing a stir bar, 1.5064 g of the polyamic acid solution (PAA-7) obtained in Synthesis Example 17 and 1.1675 g of the polyamic acid solution (PAA-3) obtained in Synthesis Example 13 were taken. Then, 3.7665 g of NMP and 1.6164 g of BCS were added and stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal aligning agent (B-2).

(Comparative Example 3)
In a 20 ml sample tube containing a stir bar, 1.4819 g of the polyamic acid solution (PAA-8) obtained in Synthesis Example 18 and 2.1329 g of the polyamic acid solution (PAA-4) obtained in Synthesis Example 14 were taken. NMP (2.8033 g) and BCS (1.6191 g) were added and stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal aligning agent (B-3).

(Comparative Example 4)
Into a 20 ml sample tube containing a stir bar, 0.9658 g of the polyamic acid solution (PAA-9) obtained in Synthesis Example 19 and 3.3279 g of the polyamic acid solution (PAA-5) obtained in Synthesis Example 15 were taken. Then, 2.1364 g of NMP and 1.6117 g of BCS were added and stirred for 30 minutes with a magnetic stirrer to obtain a liquid crystal aligning agent (B-4).

(Comparative Example 5)
In a 20 ml sample tube containing a stir bar, 1.0459 g of the polyamic acid solution (PAA-10) obtained in Synthesis Example 20 and 1.1662 g of the polyamic acid solution (PAA-3) obtained in Synthesis Example 13 were taken. Then, 4.2537 g of NMP and 1.6159 g of BCS were added and stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal aligning agent (B-5).

(Comparative Example 6)
In a 20-ml sample tube containing a stir bar, 1.439 g of the polyamic acid solution (PAA-11) obtained in Synthesis Example 21 and 1.1662 g of the polyamic acid solution (PAA-3) obtained in Synthesis Example 13 were taken. Then, 3.824 g of NMP and 1.6237 g of BCS were added and stirred for 30 minutes with a magnetic stirrer to obtain a liquid crystal aligning agent (B-6).

(Comparative Example 7)
Into a 20 ml sample tube containing a stir bar, 0.7388 g of the polyamic acid solution (PAA-12) obtained in Synthesis Example 22 and 2.3087 g of the polyamic acid solution (PAA-2) obtained in Synthesis Example 12 were taken. Then, 3.3915 g of NMP and 1.6510 g of BCS were added and stirred for 30 minutes with a magnetic stirrer to obtain a liquid crystal aligning agent (B-7).

(Comparative Example 8)
In a 20 ml sample tube containing a stir bar, 0.9645 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 9 and 3.3282 g of the polyamic acid solution (PAA-5) obtained in Synthesis Example 15 are taken. Then, 2.2074 g of NMP and 1.6223 g of BCS were added and stirred for 30 minutes with a magnetic stirrer to obtain a liquid crystal aligning agent (B-8).

(Comparative Example 9)
In a 20-ml sample tube containing a stir bar, 0.9954 g of the polyamic acid solution (PAA-13) obtained in Synthesis Example 23 and 2.1578 g of the polyamic acid solution (PAA-4) obtained in Synthesis Example 14 were taken. NMP (3.2750 g) and BCS (1.6107 g) were added and stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal aligning agent (B-9).

(Example 10)
The liquid crystal aligning agent (A-1) obtained in Example 1 was filtered through a 1.0 μm membrane filter, spin-coated on a glass substrate with a transparent electrode, and dried on a hot plate at a temperature of 80 ° C. for 5 minutes. Then, an imidized film having a film thickness of 100 nm was formed by baking for 20 minutes in a hot air circulating oven at 230 ° C. This coating film is rubbed with a rayon cloth (roll diameter: 120 mm, rotation speed: 300 rpm, moving speed: 20 mm / sec, pushing amount: 0.2 mm), cleaned by irradiating with ultrasonic waves in pure water for 1 minute, and air blow After removing the water droplets at, the substrate was dried at 80 ° C. for 10 minutes to obtain a substrate with a liquid crystal alignment film. Two substrates with such a liquid crystal alignment film are prepared, and a 6 μm spacer is sprayed on the liquid crystal alignment film surface of one of the substrates, and then combined so that the rubbing directions of the two substrates are antiparallel, The periphery was sealed and the empty cell having a cell gap of 6 μm was produced.
Liquid crystals (MLC-6608, manufactured by Merck & Co., Inc.) were vacuum-injected into this empty cell at room temperature, and the inlet was sealed to obtain a liquid crystal cell. The liquid crystal cell was measured for pretilt angle and residual DC. The results are shown in Table 1.

(Example 11) to (Example 18) and (Comparative Example 10) to (Comparative Example 18)
A liquid crystal cell was produced in the same manner as in Example 10 except that each of the “liquid crystal aligning agents” shown in Table 1 below was used. For each liquid crystal cell, the pretilt angle and the residual DC were measured. The results are shown in Table 1.

(Example 19)
The liquid crystal aligning agent (A-1) obtained in Example 1 was filtered through a 1.0 μm membrane filter, spin-coated on a glass substrate with a transparent electrode, and dried on a hot plate at a temperature of 80 ° C. for 5 minutes. Then, an imidized film having a film thickness of 100 nm was formed by baking for 20 minutes in a hot air circulating oven at 230 ° C. This coating film is rubbed with a rayon cloth (roll diameter: 120 mm, rotation speed: 300 rpm, moving speed: 20 mm / sec, pushing amount: 0.2 mm), cleaned by irradiating with ultrasonic waves in pure water for 1 minute, and air blow After removing the water droplets at, the substrate was dried at 80 ° C. for 10 minutes to obtain a substrate with a liquid crystal alignment film. Two substrates with such a liquid crystal alignment film are prepared, and a 6 μm spacer is dispersed on the liquid crystal alignment film surface of one of the substrates, and then the two substrates are combined so that the alignment directions of the two substrates are twisted from parallel to 85 degrees. The periphery was sealed leaving the inlet, and an empty cell with a cell gap of 6 μm was produced.
A twisted nematic liquid crystal (MLC-2003 (C080), manufactured by Merck & Co., Inc.) was vacuum-injected into this empty cell at room temperature, and the injection port was sealed to obtain a liquid crystal cell. The liquid crystal cell was measured for pretilt angle and residual DC. The results are shown in Table 2.

(Example 20) to (Example 25) and (Comparative Example 19) to (Comparative Example 25)
A liquid crystal cell was produced in the same manner as in Example 19 except that each of the “liquid crystal aligning agents” shown in Table 2 below was used. For each liquid crystal cell, the pretilt angle and the residual DC were measured. The results are shown in Table 2.

The liquid crystal aligning agent of the present invention is widely useful for forming a liquid crystal alignment film such as in a TN element, STN element, TFT liquid crystal element, and further in a vertical alignment type liquid crystal display element.
The entire contents of the specification, claims, and abstract of Japanese Patent Application No. 2010-242526 filed on Oct. 28, 2010 are incorporated herein as the disclosure of the present invention.

Claims (10)

A polyamic acid ester having a structural unit of the following formula (1), a polyamic acid having a structural unit of the following formula (2), and an organic solvent, wherein the polyamic acid ester has the following formulas (3) and (4) And a liquid crystal aligning agent having a side chain structure having a pretilt angle developing ability, comprising at least one selected from the group consisting of (5) .

Wherein X ₁ and X ₂ are tetravalent organic groups, Y ₁ and Y ₂ are divalent organic groups, R ₁ is an alkyl group having 1 to 5 carbon atoms, and A ₁ , A ₂ is independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkenyl group or alkynyl group having 2 to 10 carbon atoms.

(In Formula (3), Z < ₁ > and Z < ₃ > are at least 1 sort (s) chosen from the group which consists of a single bond or following formula (B-1)-(B-16) each independently. , Z ₂ may have a single bond or a substituent, from a group consisting of an alkylene group having 1 to 10 carbon atoms, an alkenylene group having 2 to 10 carbon atoms, an alkynylene group having 2 to 10 carbon atoms, and an arylene group. Z ₄ is at least one selected, and Z ₄ is an optionally substituted aliphatic ring having 3 to 20 carbon atoms, an aromatic ring having 6 to 30 carbon atoms and a heterocyclic ring having 1 to 20 carbon atoms. At least one divalent cyclic group selected from the group consisting of the above, or a divalent organic group having 12 to 25 carbon atoms having a steroid skeleton, and Z ₅ may have a substituent, and the number of carbon atoms may be 3 -20 aliphatic ring, C6-C30 aromatic ring and C1-C20 Is at least one divalent cyclic group selected from the group consisting of heterocycle, a is an integer of 0 to 4, Z ₆ may have a substituent, an alkyl having 1 to 18 carbon atoms And at least one selected from the group consisting of a group, a fluorine-containing alkyl group having 1 to 18 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms, and a fluorine-containing alkoxyl group having 1 to 18 carbon atoms, and b is 1 to 4 Is an integer.
In Formula (4), W ₁ may have a substituent, and may be substituted from a group consisting of an aliphatic ring having 3 to 20 carbon atoms, an aromatic ring having 6 to 30 carbon atoms, and a heterocyclic ring having 1 to 20 carbon atoms. Is at least one selected trivalent cyclic group or a trivalent organic group having 12 to 25 carbon atoms having a steroid skeleton, W ₂ has the same definition as Z _{5 in} formula (3) , and c is W 4 is an integer of 0 to 4, W ₃ is the same definition as Z ₂ of formula (3) , W ₄ is the same definition as Z ₆ of formula (3) , d is an integer of 0 to 4, e is an integer of 1-4.
In Formula (5), E ₁ has the same definition as Z ₁ and Z ₃ in Formula (3) , E ₂ is an alkyl group having 4 to 30 carbon atoms or a fluorine-containing alkyl group, and f is 1 to It is an integer of 4. )

(In formulas (B-1) to (B-16), each R ₂ is independently a hydrogen atom or an optionally substituted alkyl group, alkenyl group, alkynyl group, aryl, which may have a substituent. Group or a combination thereof.)   The content of the polyamic acid ester and the content of the polyamic acid are 1/9 to 9/1 in a mass ratio of (content of polyamic acid ester / content of polyamic acid). Liquid crystal aligning agent.   The liquid crystal aligning agent according to claim 1 or 2, wherein a total content of the polyamic acid ester and the polyamic acid is 0.5 to 15% by mass with respect to the organic solvent. In the above formula (1), part or all of Y ₁ is a divalent organic group (Y ₁ ′) having at least one structure selected from the above formulas (3) to (5). The liquid crystal aligning agent in any one of 1-3 . The ratio of the _{Y 1} 'is the liquid crystal aligning agent of claim 4 for the entire _{Y 1,} 1 to 50 mol%. The liquid crystal aligning agent according to claim 5 , wherein the structure of Y ₁ ′ is at least one kind of structure selected from the following formulas [1-1] to [1-3].

(In the formulas [1-1] to [1-3], A ₃ and A ₄ are each independently a single bond or an alkyl group having 1 to 10 carbon atoms, and A ₅ is a single bond or 1 carbon atom. Is a divalent organic group having ˜20, A ₆ is a nitrogen atom or a trivalent organic group having 1 to 30 carbon atoms, and A ₇ and A ₈ are each independently divalent having 1 to 30 carbon atoms. Z is a side chain structure represented by the above formula (3) or (5), and W is a side chain structure represented by the above formula (4). The liquid crystal alignment according to any one of claims 1 to 6 , wherein X ₁ and X ₂ in the formulas (1) and (2) are each independently at least one selected from structures represented by the following formulas: Agent.

The liquid crystal aligning agent of according to any one of claims 1 to 7 at least one of the formula _(2), Y 2 is selected from structures represented by the following formula.

The manufacturing method of the liquid crystal aligning film which apply | coats and bakes the liquid crystal aligning agent in any one of Claims 1-8 . The manufacturing method of the liquid crystal aligning film which irradiates the polarized radiation to the film obtained by apply | coating and baking the liquid crystal aligning agent in any one of Claims 1-8 .