KR20230145112A - Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display device - Google Patents

Abstract

(R₁ ∼ R₄ 는 각각 독립적으로 수소 원자, 할로겐 원자, 탄소수 1 ∼ 6 의 알킬기, 탄소수 2 ∼ 6 의 알케닐기, 탄소수 2 ∼ 6 의 알키닐기, 불소 원자를 함유하는 탄소수 1 ∼ 6 의 1 가의 유기기, 또는 페닐기를 나타내고, R₁ ∼ R₄ 중 적어도 하나는 상기 정의 중의 수소 원자 이외의 기를 나타낸다. R 및 Z 는 각각 독립적으로, 수소 원자 또는 1 가의 유기기를 나타낸다. Y₁ 은 하기 식 (H) 로 나타내는 2 가의 유기기를 나타낸다.)
[화학식 2]

(R_a 는, 하이드록시기, 할로겐 원자 또는 탄소수 1 ∼ 3 의 1 가의 유기기를 나타낸다. a 는 1 ∼ 4 이다. R_a 가 복수 존재하는 경우, 각각 동일해도 되고 상이해도 된다. * 는 결합손을 나타낸다.)Providing a liquid crystal aligning agent, a liquid crystal aligning film, and a liquid crystal display element that can suppress afterimages generated by long-term alternating current driving and reduce the variation in the twist angle of the liquid crystal within the plane of the liquid crystal aligning film. do.
(Solution) Containing at least one type of polymer (A) selected from the group consisting of a polyimide precursor having a repeating unit (a1) represented by formula (1) and a polyimide that is an imidate of the polyimide precursor. Characterized by a liquid crystal aligning agent.
[Formula 1]

(R ₁ to R ₄ are each independently a hydrogen atom, a halogen atom, an alkyl group with 1 to 6 carbon atoms, an alkenyl group with 2 to 6 carbon atoms, an alkynyl group with 2 to 6 carbon atoms, or a fluorine atom containing 1 to 6 carbon atoms. Represents a valent organic group or a phenyl group, and at least one of R ₁ to R ₄ represents a group other than a hydrogen atom as defined above.R and Z each independently represent a hydrogen atom or a monovalent organic group. Y ₁ is represented by the following formula (H) represents a divalent organic group.)
[Formula 2]

(R _a represents a hydroxy group, a halogen atom, or a monovalent organic group having 1 to 3 carbon atoms. a is 1 to 4. When multiple R _a exists, they may be the same or different. * represents a bond represents.)

Description

Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display device

The present invention relates to a liquid crystal aligning agent, a liquid crystal aligning film, and a liquid crystal display element.

Liquid crystal displays are widely used as display units for personal computers, smartphones, mobile phones, televisions, etc. A liquid crystal display device usually includes a liquid crystal layer sandwiched between a display element substrate and a color filter substrate, a pixel electrode and a common electrode that apply an electric field to the liquid crystal layer, an alignment film that controls the orientation of liquid crystal molecules in the liquid crystal layer, and a pixel electrode supplied to the pixel electrode. It is equipped with a thin film transistor (TFT) that switches electrical signals. As driving methods for liquid crystal molecules, longitudinal electric field methods such as the TN method and VA method, and transverse electric field methods such as the IPS (In Plane Switching) driving method and FFS (Fringe Field Switching) driving method are known.

The liquid crystal alignment film that is most widespread industrially is a so-called rubbing process in which the surface of a film formed on an electrode substrate made of polyamic acid and/or polyimide imidized thereof is rubbed in one direction with a cloth such as cotton, nylon, or polyester. It is manufactured by carrying out processing. The rubbing treatment is an industrially useful method that is simple and highly productive. However, with the increase in performance, high definition, and enlargement of liquid crystal display elements, various problems such as scratches on the surface of the alignment film generated during the rubbing treatment, oscillation, influence by mechanical force or static electricity, and even unevenness within the alignment treatment surface are encountered. is becoming clear. As an alignment treatment method that replaces the rubbing treatment, a photo-alignment method that imparts liquid crystal alignment ability by irradiating polarized radiation is known. Photo-alignment methods using a photoisomerization reaction, a photo-crosslinking reaction, and a photodecomposition reaction have been proposed (for example, see Non-Patent Document 1 and Patent Documents 1 and 2).

Japanese Patent Publication No. 9-297313 Japanese Patent Publication No. 2004-206091

「Functional Materials」, November 1997, Vol.17, No.11, pages 13 to 22

The liquid crystal alignment film used in the liquid crystal display element of the IPS drive system or FFS drive system requires a high alignment regulation force to suppress afterimages (hereinafter also referred to as AC afterimages) generated by long-term alternating current drive. In addition, when performing alignment treatment by a photo-alignment method, the amount of light irradiation is a factor that affects energy cost and production speed, so it is desirable to be able to perform the alignment treatment with a small amount of light irradiation.

However, as a result of the present inventor's examination, for example, the liquid crystal alignment film that can realize liquid crystal alignment with a small amount of light irradiation in the alignment treatment by the photo-alignment method has the light irradiation amount at which a liquid crystal alignment film that can suppress AC afterimages is obtained. It has become clear that there are problems such as a narrow range of light irradiation amount from which a liquid crystal aligning film with a narrow range and small variation (non-uniformity) in the twist angle of the liquid crystal within the plane of the liquid crystal aligning film is narrow. Therefore, the risk of AC afterimage occurring due to liquid crystal driving increases, making it difficult to obtain a liquid crystal display element with high display quality excellent in contrast, and in a part of the liquid crystal alignment film obtained when increasing the screen size of the liquid crystal display element is attempted. There is concern that liquid crystal alignment becomes incomplete and that when image display is performed for a long time, variations in in-plane brightness occur and display quality deteriorates.

Therefore, the object of the present invention is to suppress the afterimage generated by long-term alternating current drive even when the range of light irradiation amount in the alignment treatment by the photo-alignment method is small, and furthermore, within the plane of the liquid crystal alignment film. To provide a liquid crystal aligning agent capable of obtaining with good efficiency a liquid crystal alignment film with high characteristics such as the ability to reduce the variation (non-uniformity) of the twist angle of the liquid crystal, the liquid crystal alignment film, and a liquid crystal display element using the liquid crystal alignment film. It's in the thing.

As a result of extensive research, the present inventor discovered that the above-described problem could be solved by using a liquid crystal aligning agent containing a specific component, and came to complete the present invention.

The present invention specifically has the following aspects.

Characterized by containing at least one type of polymer (A) selected from the group consisting of a polyimide precursor having a repeating unit (a1) represented by the following formula (1) and a polyimide that is an imidate of the polyimide precursor. Liquid crystal orientation agent.

[Formula 1]

(In formula (1), R ₁ to R ₄ each independently contain a hydrogen atom, a halogen atom, an alkyl group with 1 to 6 carbon atoms, an alkenyl group with 2 to 6 carbon atoms, an alkynyl group with 2 to 6 carbon atoms, or a fluorine atom. represents a monovalent organic group having 1 to 6 carbon atoms or a phenyl group, and at least one of R ₁ to R ₄ represents a group other than a hydrogen atom as defined above. R and Z each independently represent a hydrogen atom or a monovalent organic group. Y ₁ represents a divalent organic group represented by the formula (H) below.)

[Formula 2]

(In the formula (H), R _a represents a hydroxy group, a halogen atom, or a monovalent organic group having 1 to 3 carbon atoms. a is an integer of 1 to 4. In addition, when multiple R _a is present, each is the same. It can be done or it can be different. * indicates a bond.)

In addition, in this specification, “integer” may be omitted in cases where it is self-evident that “a is an integer of 1 to 4,” etc. In addition, * represents a bond in both cases.

According to the present invention, for example, even when the range of light irradiation amount in the alignment treatment by the photo-alignment method is small, AC afterimage can be suppressed, and further, the deviation of the twist angle of the liquid crystal within the plane of the liquid crystal alignment film ( A liquid crystal aligning agent that can obtain a liquid crystal aligning film with high characteristics such as the ability to reduce non-uniformity) with good efficiency, the liquid crystal aligning film, and a liquid crystal display element using the liquid crystal aligning film can be provided.

The mechanism by which the above-mentioned effects of the present invention are obtained is not necessarily clear, but is considered to be one of the factors described below. The polymer (A) contained in the liquid crystal aligning agent of this invention contains a repeating unit derived from substituted phenylenediamine. By including such a repeating unit, it becomes possible to adjust the imidation rate during thermal imidation and the intermolecular interaction of the polymer, and it becomes easy to control the glass transition temperature of the polymer during orientation treatment. Therefore, it is thought that the anisotropy of the alignment film was improved because the mobility of the polymer during the alignment treatment was increased, and the above effect was obtained.

1 is a schematic cross-sectional view of an example of a transverse electric field liquid crystal display element provided with a liquid crystal aligning film obtained from the liquid crystal aligning agent of the present invention.
Fig. 2 is a schematic cross-sectional view of another example of a transverse electric field liquid crystal display element provided with a liquid crystal aligning film obtained from the liquid crystal aligning agent of the present invention.

＜Polymer (A)＞

The liquid crystal aligning agent of the present invention is at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1) represented by the following formula (1) and a polyimide that is an imidate of the polyimide precursor (A) ) contains. In addition, the polymer (A) may be composed of one type or two or more types.

[Formula 3]

In the formula (1), R ₁ to R ₄ each independently represent a hydrogen atom, a halogen atom, an alkyl group with 1 to 6 carbon atoms, an alkenyl group with 2 to 6 carbon atoms, an alkynyl group with 2 to 6 carbon atoms, or a fluorine atom. It represents a monovalent organic group containing 1 to 6 carbon atoms or a phenyl group, and at least one of R ₁ to R ₄ represents a group other than a hydrogen atom as defined above.

R and Z each independently represent a hydrogen atom or a monovalent organic group. Y ₁ represents a divalent organic group represented by the formula (H) below.

[Formula 4]

In the above formula (H), R _a represents a hydroxy group, a halogen atom, or a monovalent organic group having 1 to 3 carbon atoms. a is 1 to 4. Moreover, when there are two or more R _a , each may be the same or different.

The halogen atom for R _a in the formula (H) includes a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and among these, a fluorine atom is preferable. In the above formula (H), a is preferably 1 to 3, more preferably 1 to 2, from the viewpoint of obtaining the effects of the present invention well.

The divalent organic group represented by the above formula (H) is preferably a divalent organic group represented by the following formula (H') from the viewpoint of obtaining the effects of the present invention well.

[Formula 5]

(R _a and a have the same meaning as the above formula (H))

Specific examples of the alkyl group having 1 to 6 carbon atoms for R ₁ to R ₄ include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, and tert-butyl group. , n-pentyl group, etc. Specific examples of the alkenyl group having 2 to 6 carbon atoms for R ₁ to R ₄ include vinyl group, propenyl group, butenyl group, etc., and these may be linear or branched. Specific examples of the alkynyl group having 2 to 6 carbon atoms for R ₁ to R ₄ include ethynyl group, 1-propynyl group, 2-propynyl group, 1-butynyl group, 2-butynyl group, 3-butynyl group, etc. can be mentioned. The halogen atom for R ₁ to R ₄ includes the halogen atom exemplified as R _a in the formula (H). Examples of the monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom for R ₁ to R ₄ include fluoromethyl group, trifluoromethyl group, pentafluoroethyl group, and pentafluoropropyl group. . From the viewpoint of high photoreactivity, it is preferable that R ₁ to R ₄ are each independently a hydrogen atom or a methyl group, at least one of R ₁ to R ₄ is a methyl group, and at least two of R ₁ to R ₄ are methyl groups. desirable. More preferably, R ₁ and R ₄ are methyl groups and R ₂ and R ₃ are hydrogen atoms.

The monovalent organic group in the formula (H) includes an alkyl group, and at least part of the hydrogen atoms on the alkyl group are halogen atoms (specific examples of the halogen atoms include the halogen atoms exemplified as R _a in the formula (H) above. Examples include a halogenated alkyl group, an alkoxy group, and a halogenated alkoxy group and an alkenyl group in which at least a portion of the hydrogen atoms on the alkoxy group is substituted with a halogen atom. The alkyl group having 1 to 3 carbon atoms includes those having 1 to 3 carbon atoms among the structures exemplified for the alkyl groups for R ₁ to R ₄ , and the halogenated alkyl group includes fluoromethyl and trifluoromethyl. , pentafluoroethyl group, pentafluoropropyl group, etc. Among them, the monovalent organic group having 1 to 3 carbon atoms is preferably a methyl group or a methoxy group.

The divalent organic group represented by the above formula (H) is preferably a divalent organic group represented by any of the following formulas (h-1) to (h-16) from the viewpoint of obtaining the effects of the present invention well.

[Formula 6]

The monovalent organic group for R and Z in the above formula (1) is a monovalent hydrocarbon group having 1 to 20 carbon atoms, and the methylene group of the hydrocarbon group is -O-, -S-, -CO-, and -COO -, -COS-, -NR ³ -, -CO-NR ³ -, -Si(R ³ ) ₂ - (However, R ³ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms, and R ³ is (if there is more than one, each R ³ may be the same or different), a monovalent group A substituted with -SO ₂ -, etc., such a monovalent hydrocarbon group or a hydrogen atom bonded to a carbon atom of the monovalent group A At least one halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom, etc.), hydroxy group, alkoxy group, nitro group, amino group, mercapto group, nitroso group, alkylsilyl group, alkoxysilyl group, silanol group , a monovalent group formed by substitution with a sulfino group, phosphino group, carboxyl group, cyano group, sulfo group, acyl group, etc., a monovalent group having a heterocycle, etc. The monovalent organic group for R and Z in the above formula (1) is an alkyl group with 1 to 10 carbon atoms, an alkenyl group with 2 to 10 carbon atoms, an alkynyl group with 2 to 10 carbon atoms, a tert-butoxycarbonyl group, or A 9-fluorenylmethoxycarbonyl group is preferable, an alkyl group having 1 to 3 carbon atoms is more preferable, and a methyl group is even more preferable.

From the viewpoint of obtaining the effects of the present invention, R and Z are each independently preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably a hydrogen atom or a methyl group.

From the viewpoint of obtaining the effects of the present invention, the polymer (A) is a polyhydric acid having a repeating unit (a1) represented by the formula (1) and a repeating unit (a2) represented by the formula (2) below. It may be at least one type of polymer selected from the group consisting of a mead precursor and a polyimide that is an imidate of the polyimide precursor. Additionally, the repeating unit (a2) may be composed of one type or two or more types.

[Formula 7]

In the formula (2), R ₁ to R ₄ , R and Z have the same meaning as in the formula (1). Y ₂ represents a divalent organic group represented by the formula (O) below.

[Formula 8]

In the formula (O), Ar each independently represents a benzene ring, a biphenyl structure, or a naphthalene ring. Any hydrogen atom on the Ar ring may be substituted with a halogen atom or a monovalent organic group. Q ₂ is -(CH ₂ ) _n - (n is 2 to 18), or a portion of -(CH ₂ ) _n - is -O-, -C(=O)- or -OC(=O)- Indicates a group substituted with any of the following.

In the formula (O), examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of the monovalent organic group include an alkyl group with 1 to 3 carbon atoms, an alkenyl group with 2 to 3 carbon atoms, an alkynyl group with 2 to 3 carbon atoms, a monovalent organic group with 1 to 3 carbon atoms containing a fluorine atom, etc. I can hear it. Specific examples of these monovalent organic groups include those exemplified by R ₁ to R ₄ above.

As the divalent organic group represented by the above formula (O), a divalent organic group represented by any of the following formulas (o-1) to (o-14) is preferable from the viewpoint of improving the liquid crystal orientation. In formula (o-10), m is preferably 2. In (o-14), m is more preferably 0 or 2.

[Formula 9]

[Formula 10]

(In equation (o-14), the two m are independent.)

From the viewpoint of obtaining the effect of the present invention, the polymer (A) is composed of the repeating unit (a1) represented by the formula (1), or the repeating unit (a1) and the repeating unit (a2) represented by the formula (2). ) together with a polyimide precursor having at least one selected from the group consisting of a repeating unit (a2') represented by the following formula (2') and a repeating unit (a3) represented by the following formula (3), and a polyimide thereof At least one type of polymer selected from the group consisting of polyimide, which is an imidate of a precursor, may be used.

[Formula 11]

In the above formulas ( ₂ ') and ( ₃ ), X _{2' and} N(D)- (D represents a carbamate-based protecting group)” represents a divalent organic group having 6 to 30 carbon atoms in the molecule. R and Z have the same meaning as in the case of formula (1) above.

[Formula 12]

In the above formula (O2), m is an integer of 0 to 2, and Ar _2' represents an unsubstituted or substituted benzene ring. However, when m is 0, Ar _2' represents an unsubstituted benzene ring, and when m is 1 to 2, Ar _2' each independently represents an unsubstituted benzene ring or an arbitrary hydrogen atom on the benzene ring. , a halogen atom or a monovalent organic group (for example, an alkyl group with 1 to 3 carbon atoms, an alkenyl group with 2 to 3 carbon atoms, an alkynyl group with 2 to 3 carbon atoms, a monovalent organic group with 1 to 3 carbon atoms containing a fluorine atom) etc.) represents a substituted benzene ring. Q _2' represents a single bond or -O-. When there are two or more Ar _2' and Q _2' , they may be the same or different.

As the divalent organic group represented by the above formula (O2), a divalent organic group represented by any of the following formulas (o2-1) to (o2-12) is preferable from the viewpoint of reducing the occurrence of AC afterimages.

[Formula 13]

D of Y ₃ in the above formula (3) represents a carbamate-based protecting group, and examples of the carbamate-based protecting group include tert-butoxycarbonyl group or 9-fluorenylmethoxycarbonyl group. . Specific examples of Y ₃ include a divalent organic group represented by the following formula (Dx).

[Formula 14]

In the formula (Dx), Q ₅ is a single bond, -(CH ₂ ) _n - (n is 1 to 20), or any -CH ₂ - of -(CH ₂ ) _n - is -O-, -Si(CH ₃ ) ₂ -, -COO-, -OCO-, -NQ ₉ -, -NQ ₉ -CO-, -CO-NQ ₉ -, -NQ ₉ -CO-NQ ₁₀ -, -NQ ₉ - It is a group substituted with COO- or -O-COO-, and Q ₉ and Q ₁₀ each independently represent a hydrogen atom or a monovalent organic group.

Q ₆ and Q ₇ each independently represent a group having -H, -NHD, -N(D) ₂ , -NHD, or a group having -N(D) ₂ . However, when m = 0, Q ₆ has a carbamate-based protecting group, and when m = 1, at least one of Q ₅ , Q ₆ and Q ₇ has a carbamate-based protecting group in the group. In addition, when Q ₆ and Q ₇ represent a group having -NHD or a group having -N(D) ₂ , the preferred carbon number of Q ₆ and Q ₇ is 1 to 30, more preferably 1 to 8. am.

The monovalent organic groups for Q ₉ and Q ₁₀ include an alkyl group with 1 to 3 carbon atoms, an alkenyl group with 2 to 3 carbon atoms, an alkynyl group with 2 to 3 carbon atoms, and a monovalent organic group with 1 to 3 carbon atoms containing a fluorine atom. and specific examples include those exemplified by R ₁ to R ₄ above and those having 1 to 3 carbon atoms.

Preferred specific examples of Y ₃ include a divalent organic group represented by any of the following formulas (Y3-1) to (Y3-9) from the viewpoint of reducing AC afterimages. Boc represents a tert-butoxycarbonyl group.

[Formula 15]

In the above formula (2') and formula (3), X _{2 '} and and tetravalent organic groups derived from anhydrides. From the viewpoint of obtaining the effects of the present invention, it is more preferable that X _2' and X ₃ are tetravalent organic groups represented by the following formula (g).

[Formula 16]

(R ₁ to R ₄ have the same meaning as R ₁ to R ₄ in the above formula (1))

[Formula 17]

[Formula 18]

The aromatic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of a carboxyl group bonded to an aromatic ring such as a benzene ring or naphthalene ring. Specific examples include a tetravalent organic group represented by any of the following formulas (Xa-1) to (Xa-2), and a tetravalent organic group represented by any of the following formulas (Xr-1) to (Xr-7). there is.

[Formula 19]

(x and y are each independently a single bond, ether, carbonyl, ester, alkanediyl group having 1 to 10 carbon atoms, 1,4-phenylene, sulfonyl, or amide bond. j and k are 0 or 1.)

[Formula 20]

The tetravalent organic group represented by the above formula (Xa-1) or (Xa-2) may have a structure represented by any of the following formulas (Xa-3) to (Xa-19).

[Formula 21]

[Formula 22]

The polymer (A) further has a repeating unit (a4) represented by the following formula (4) in addition to the repeating unit (a1), repeating unit (a2), repeating unit (a2'), and repeating unit (a3). At least one type of polymer selected from the group consisting of a polyimide precursor and a polyimide that is an imidate of the polyimide precursor may be used.

[Formula 23]

In the above formula (4), X ₄ represents a tetravalent organic group, and Y ₄ represents a divalent organic group. R and Z have the same meaning as R and Z in the above formula (1), respectively. However, Y ₄ has a group “-N(D)- (D represents a carbamate-based protecting group)” in the molecule, and is a divalent organic group with 6 to 30 carbon atoms excluding D and the above formula (O2) Structures other than the indicated divalent organic group are shown. In _{addition ,} when It represents the structure.

Specific examples of X ₄ include the tetravalent organic groups exemplified for X _2′ above. From the viewpoint of obtaining the effects of the present invention, it is preferable _that And, it is more preferable that it is a tetravalent organic group represented by the above formula (g).

Specific examples of the divalent organic group of Y ₄ include, in addition to the divalent organic groups exemplified in the above formula (H) and the above formula (O), divalent organic groups derived from diamine (two from diamine) described below. and divalent organic groups excluding amino groups).

4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminodiphenylmethane; Diamine which has a photo-alignment group, such as diamine represented by the following formula (g-1) - (g-9); diamines having a urea bond, such as diamines represented by the following formulas (u-1) to (u-3) (however, the diamines do not have a carbamate-based protecting group in the molecule); Diamines having an amide bond, such as diamines represented by the following formulas (u-4) to (u-7) (however, the diamines do not have a carbamate-based protecting group in the molecule); At least one nitrogen atom-containing structure selected from the group consisting of a nitrogen atom-containing heterocycle, a secondary amino group, and a tertiary amino group (hereinafter also referred to as a nitrogen atom-containing structure. However, the secondary amino group and the tertiary amino group) diamine having an amino group (the amino group does not bind to a carbamate-based protecting group); 2,4-diaminophenol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol; Diamines having a carboxyl group, such as 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 3,5-diaminobenzoic acid, or diamine compounds represented by the following formulas (3b-1) to (3b-4); 4-(2-(methylamino)ethyl)aniline, 4-(2-aminoethyl)aniline, 4,4'-diaminobenzophenone, 1-(4-aminophenyl)-1,3,3-trimethyl- 1H-indan-5-amine, 1-(4-aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H-inden-6-amine; diamines having a photopolymerizable group at the terminal, such as 2-(2,4-diaminophenoxy)ethyl methacrylate and 2,4-diamino-N,N-diallylaniline; Cholestanyloxy-3,5-diaminobenzene, Cholestanyloxy-3,5-diaminobenzene, Cholestanyloxy-2,4-diaminobenzene, Cholestanyl 3,5-diaminobenzoate, diamines having a steroid skeleton such as 3,5-diaminobenzoic acid cholesthenyl, 3,5-diaminobenzoic acid lanostanyl, and 3,6-bis(4-aminobenzoyloxy)cholestane; Diamine represented by the following formulas (V-1) to (V-6); Diamines having siloxane bonds such as 1,3-bis(3-aminopropyl)-tetramethyldisiloxane; Diamines having oxazoline ring structures such as the following formulas (Ox-1) and (Ox-2); 1-(4-(2,4-diaminophenoxy)ethoxy)phenyl)-2-hydroxy-2-methylpropanone, 2-(4-(2-hydroxy-2-methylpropanoyl) Phenoxy) ethyl-3,5-diaminobenzoate, 4,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, etc. Divalent oils derived from diamines such as diamines having a radical polymerization initiator function A group represented by any of the formulas (Y-1) to (Y-167) described in WO2018/117239.

[Formula 24]

[Formula 25]

[Formula 26]

In the above formula (3b-1), A ¹ is a single bond, -CH ₂ -, -C ₂ H ₄ -, -C(CH ₃ ) ₂ -, -CF ₂ -, -C(CF ₃ ) ₂ -, -O-, -CO-, -NH-, -N(CH ₃ )-, -CONH-, -NHCO-, -CH ₂ O-, -OCH ₂ -, -COO-, -OCO-, -CON( CH ₃ )- or -N(CH ₃ )CO- is represented, m1 and m2 are each independently 0 to 4, and m1+m2 is 1 to 4.

In the above formula (3b-2), m3 and m4 are each independently 1 to 5. In the above formula (3b-3), A ² represents a straight-chain or branched alkyl group having 1 to 5 carbon atoms, and m 5 has 1 to 5 carbon atoms. In the formula (3b-4), A ³ and A ⁴ are each independently a single bond, -CH ₂ -, -C ₂ H ₄ -, -C(CH ₃ ) ₂ -, -CF ₂ -, -C (CF ₃ ) ₂ -, -O-, -CO-, -NH-, -N(CH ₃ )-, -CONH-, -NHCO-, -CH ₂ O-, -OCH ₂ -, -COO-, It represents -OCO-, -CON(CH ₃ )- or -N(CH ₃ )-CO-, and m6 is 1 to 4.

[Formula 27]

In _the above formulas (V-1 ^{) to} (V- ₆ ⁾ , X ^v1 to -, -NHCO-, -CON(CH ₃ )-, -NH-, -O-, -CH ₂ O-, -CH ₂ OCO-, -COO-, or -OCO-, and X ^v5 is -O -, -CH ₂ O-, -CH ₂ OCO-, -COO-, or -OCO-. X _a is a single bond, -O-, -NH-, -O-(CH ₂ ) _m -O- (m is 1 to 6), -C(CH ₃ ) ₂ -, -CO-, -( CH ₂ ) _m - (m is 1 to 6), -SO ₂ -, -OC(CH ₃ ) ₂ -, -CO-(CH ₂ ) _m - (m is 1 to 6), -NH-( CH ₂ ) _m - (m represents 1 to 6), -SO ₂ -(CH ₂ ) _m - (m represents 1 to 6), -CONH-(CH ₂ ) _m - (m represents 1 to 6) ), -CONH-(CH ₂ ) _m -NHCO- (m is 1 to 6), -COO-(CH ₂ ) _m -OCO- (m is 1 to 6), -CONH-, -NH-( CH ₂ ) _m -NH- (m represents 1 to 6), or -SO ₂ -(CH ₂ ) _m -SO ₂ - (m represents 1 to 6), R ^v1 to R ^v4 , R ^1a ~R ^1b each independently represents an alkyl group with 1 to 20 carbon atoms, an alkoxy group with 1 to 20 carbon atoms, or an alkoxyalkyl group with 2 to 20 carbon atoms. k may be the same or different.

[Formula 28]

Examples of the nitrogen atom-containing heterocycle include pyrrole, imidazole, pyrazole, triazole, pyridine, pyrimidine, pyridazine, pyrazine, indole, benzoimidazole, purine, quinoline, isoquinoline, naphthyridine, Quinoxaline, phthalazine, triazine, carbazole, acridine, piperidine, piperazine, pyrrolidine, hexamethylene imine, etc. are mentioned. Among them, pyridine, pyrimidine, pyrazine, piperidine, piperazine, quinoline, carbazole or acridine are preferable.

The secondary amino group and tertiary amino group that the diamine having a nitrogen atom-containing structure may have are represented by the following formula (n), for example.

[Formula 29]

In the above formula (n), R represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms. “*1” represents a bond bonded to a hydrocarbon group. Examples of the monovalent hydrocarbon group of R in the formula (n) include alkyl groups such as methyl, ethyl, and propyl groups; Cycloalkyl groups such as cyclohexyl group; Aryl groups such as phenyl group and methylphenyl group can be mentioned. R is preferably a hydrogen atom or a methyl group.

Specific examples of diamines having a nitrogen atom-containing structure include, for example, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, 1,4-bis-(4-aminophenyl) )-piperazine, 3,6-diaminoacridine, compounds represented by the following formulas (Dp-1) to (Dp-8), or compounds represented by the following formulas (z-1) to (z-13) I can hear it.

[Formula 30]

[Formula 31]

[Formula 32]

From the viewpoint of obtaining the effect of the present invention, the polymer (A) preferably contains the total of the repeating unit (a1) and the imidized structural units of the repeating unit (a1) in an amount of 10 to 100 mol% of the total repeating units. It is more preferable that it contains 15 to 100 mol%. In addition, the total here also includes the case where either the repeating unit (a1) or the imidized structural unit of the repeating unit (a1) is 0 mol%. Hereinafter, when referring to the total, the case where 1 or 2 or more of the structural unit elements is 0 mol% is also included.

When the polymer (A) contains repeating units other than the repeating unit (a1) and the imidated structural units of the repeating unit (a1), the repeating unit (a1) and the imidated structural units of the repeating unit (a1) It is preferable that the total contains 10 to 95 mol% of all repeating units. The polymer (A) preferably contains the repeating unit (a1) and the total of the imidized structure and units of the repeating unit (a1) at 95 mol% or less, and more preferably at 90 mol% or less, of the total repeating units. , it is more preferable to contain 80 mol% or less. In addition, the polymer (A) preferably contains the total of the repeating unit (a1) and the imidized structural units of the repeating unit (a1) in an amount of 10 mol% or more, and preferably contains 15 mol% or more of the total repeating units. .

From the viewpoint of obtaining the effect of the present invention, the polymer (A) preferably contains the total of the repeating unit (a2) and the imidized structural units of the repeating unit (a2) of 5 mol% or more of the total repeating units, It is more preferable that it contains 10 mol% or more, more preferably 20 mol% or more, on the other hand, it is preferable that it contains 90 mol% or less, and it is more preferable that it contains 85 mol% or less. In addition, from the viewpoint of obtaining the effect of the present invention well, the polymer (A) has a total of the repeating unit (a2) and the imidized structural units of the repeating unit (a2) of 10 to 90 mol of the total repeating units. It is preferable to include %.

From the viewpoint of obtaining the effect of the present invention, it is preferable that the total of the repeating unit (a1), the repeating unit (a2), and their imidized structural units in the polymer (A) is 10 mol% or more of the total repeating units, It is more preferable that it is 20 mol% or more. When it contains repeating units other than the repeating unit (a1), the repeating unit (a2), and their imidated structural units, the total of the repeating unit (a1), the repeating unit (a2), and their imidated structural units is 95 moles. It is preferable that it is % or less, and it is more preferable that it is 90 mol% or less.

When the polymer (A) contains at least one of the repeating unit (a2') and the imidated structural unit of the repeating unit (a2'), from the viewpoint of obtaining the effect of the present invention well, the polymer (A) contains the repeating unit (a2') The total of the imidized structural units of a2') and the repeating unit (a2') is preferably 1 to 50 mol%, more preferably 1 to 40 mol%, and 1 to 30 mol% of the total repeating units. It is more preferable to include %. When the polymer (A) contains at least one of the repeating unit (a1) and its imidated structural unit, and at least one of the repeating unit (a2) and its imidated structural unit, the repeating unit (a2') and the repeating unit ( The total of imidized structural units of a2') is preferably 5 mol% or more, and more preferably 10 mol% or more.

From the viewpoint of obtaining the effect of the present invention, the polymer (A) contains at least one of the repeating unit (a1) and its imidated structural unit, and at least one of the repeating unit (a2) and its imidized structural unit, and a repeating unit. (a2') and at least any of its imidized structural units, and the sum of the repeating unit (a1), the repeating unit (a2), the repeating unit (a2') and their imidized structural units is 30 mol of the total repeating unit. It is preferable that it is % or more, and it is more preferable that it is 40 mol% or more. When the polymer (A) contains repeating units other than the repeating unit (a1), the repeating unit (a2), the repeating unit (a2'), and their imidized structural units, the repeating unit (a1), the repeating unit ( The total of a2), the repeating unit (a2'), and their imidized structural units is preferably 95 mol% or less, and more preferably 90 mol% or less.

When the polymer (A) contains at least one of the repeating unit (a3) and the imidated structural unit of the repeating unit (a3), from the viewpoint of obtaining the effect of the present invention well, the polymer (A) contains the repeating unit (a3) The total of the imidized structures of the repeating unit (a3) is preferably 1 to 40 mol%, more preferably 1 to 30 mol%, and even more preferably 1 to 25 mol% of the total repeating units. desirable.

The polymer (A) may include a repeating unit (a2'), a repeating unit (a3), and their imidized structural units.

When the polymer (A) contains at least any of the repeating unit (a4) and its imidated structural unit, from the viewpoint of obtaining the effect of the present invention, Y ₄ is a divalent polymer having no side chain structure of 4 or more carbon atoms. It is preferably composed of at least one of the repeating unit (a4), which is an organic group, and its imidated structural unit.

Examples of the divalent organic group that does not have a side chain structure of 4 or more carbon atoms include, from the other diamines mentioned above, 2-(2,4-diaminophenoxy)ethyl methacrylate, 2,4-diamino-N,N- Diallylaniline, diamines having the above steroid skeleton, diamines represented by the above formulas (V-1) to (V-6), 1-(4-(2,4-diaminophenoxy)ethoxy)phenyl)-2 -Hydroxy-2-methylpropanone, 2-(4-(2-hydroxy-2-methylpropanoyl)phenoxy)ethyl-3,5-diaminobenzoate, N-phenyl-3,6- A divalent organic group derived from a diamine selected from the group consisting of diamines excluding diaminocarbazole, diamines represented by (z-4) and (z-6), etc. can be mentioned.

When the polymer (A) contains at least one of the repeating unit (a4) and the imidated structural unit of the repeating unit (a4), from the viewpoint of obtaining the effect of the present invention well, the polymer (A) contains the repeating unit (a4) The total of the imidized structures of the repeating unit (a4) is preferably 1 to 90 mol%, more preferably 5 to 70 mol%, and even more preferably 10 to 30 mol% of the total repeating units. desirable.

＜Polymer (B)＞

The liquid crystal aligning agent of this invention may contain a polymer (B) which does not have the said repeating unit (a1) in a molecule|numerator other than the said polymer (A). In addition, the polymer (B) may be composed of one type or two or more types. From the viewpoint of obtaining the effect of the present invention, the polymer (B) is at least one selected from the group consisting of a repeating unit (b1) represented by the following formula (5) and an imidized structural unit of the repeating unit (b1). and polymers having repeating units. In addition, the repeating unit constituting the polymer (B) may be composed of one type or two or more types.

[Formula 33]

In the above formula (5), X ₅ is a tetravalent organic group, and Y ₅ is a divalent organic group. R and Z have the same meaning as R and Z in the above formula (1), respectively.

The _tetravalent organic group for A tetravalent organic group derived from , and specific examples include the tetravalent organic group exemplified by X ₄ above. From the viewpoint of obtaining the effect of the present invention, the aliphatic or alicyclic tetracarboxylic dianhydride is composed of a cyclobutane ring structure, a cyclopentane ring structure, and a cyclohexane ring structure, especially from the viewpoint of enhancing liquid crystal orientation. Tetracarboxylic dianhydride having at least one partial structure selected from the group is preferred. More _preferable It is a tetravalent organic group represented by -2) or a tetravalent organic group represented by the above formulas (Xr-1) to (Xr-7) (these are also collectively referred to as specific tetravalent organic groups).

From the viewpoint of obtaining the effects of the present invention, it is preferable that the polymer (B) contains at least 5 mol% of the _total repeating units in the polymer (B), wherein , it is more preferable to contain 10 mol% or more.

Examples of the divalent organic group for Y ₅ include the divalent organic groups exemplified for Y ₄ above. From the viewpoint of reducing residual images from residual DC, the polymer (B) includes Y ₅ diamine having the above-mentioned urea bond, diamine having the above-mentioned amide bond, diamine having the above-mentioned nitrogen atom-containing structure, and 2,4-diaminophenol. , 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, diamine having the above carboxyl group, 4,4'-diamino Divalent organic groups derived from diphenylmethane, 3,4'-diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, p-phenylenediamine and m-phenylenediamine (These are collectively referred to as specific divalent organic groups.) It is preferable that it is a polymer containing a phosphorus repeating unit.

From the viewpoint of increasing the transmittance, the polymer (B) has two or more types of repeating units represented by the formula (5) above, and is selected from the group consisting of diamine having the above-mentioned urea bond, diamine having the above-mentioned amide bond, or diamine having the above-described nitrogen atom-containing structure. It is more preferable to include a repeating unit having Y ₅ , which is a divalent organic group derived from diamine, and a repeating unit having Y ₅ , which is a divalent organic group derived from other diamines.

Polymer (B) contains repeating units in which Y ₅ is the specific divalent organic group described above in an amount of 1 mol% or more, preferably 5 mol%, of the total repeating units contained in polymer (B), from the viewpoint of reducing afterimages resulting from residual DC. It may contain mol% or more, more preferably 10 mol% or more, and even more preferably 20 mol% or more.

From the viewpoint of reducing afterimages from residual DC, the content ratio of polymer (A) and polymer (B) (mass ratio of polymer (A)/polymer (B)) is preferably 10/90 to 90/10, and 20/90. 80 to 90/10 is more preferable, and 20/80 to 80/20 is still more preferable.

<Method for producing polymer (A) and polymer (B)>

Polyamic acid ester, polyamic acid, and polyimide, which are the polyimide precursors of the polymer (A) and polymer (B) in the present invention, and polyimide, which is their imidized product, are described in, for example, WO2013/157586. It can be synthesized using already known methods as described above.

Specifically, it is synthesized by reacting a diamine component and a tetracarboxylic acid derivative component (condensation polymerization) in a solvent. Examples of the tetracarboxylic acid derivative component include tetracarboxylic dianhydride or a derivative thereof (tetracarboxylic acid dihalogenide, tetracarboxylic acid diester, or tetracarboxylic acid diester dihalide). . When a part of polymer (A) or (B) contains an amic acid structure, for example, a polymer (polyamic acid) having an amic acid structure is obtained by reacting a tetracarboxylic dianhydride component and a diamine component. . The solvent is not particularly limited as long as it dissolves the produced polymer.

The diamine component and the tetracarboxylic acid derivative component for obtaining the polyimide precursor of the polymer (A) are, respectively, the above-mentioned formula (1), formula (2), formula (2'), and formula ( 3) Depending on the repeating unit represented by formula (4), it is selected and used so that the structure of this repeating unit is obtained.

For example, when polymer (A) has a repeating unit represented by formula (1), the diamine component includes a structure of -N(Z)-Y ₁ -N(Z)- (Y ₁ , Z A diamine (hereinafter also referred to as specific diamine) having the same definition as above) is used, and as the tetracarboxylic acid derivative component, a structure of the following formula (g) (the definitions of R ₁ to R ₄ are as above) are the same) and a tetracarboxylic acid derivative having is used.

[Formula 34]

Diamine component and tetra to be used when obtaining a polyimide precursor of polymer (A) having repeating units represented by formula (2), formula (2'), formula (3), and formula (4) of polymer (A) The carboxylic acid derivative component is selected and used according to the diamine and tetracarboxylic acid derivatives used when obtaining the polyimide precursor having a repeating unit represented by the above formula (1), respectively.

In addition, the diamine component and the tetracarboxylic acid derivative component for obtaining the polyimide precursor of the polymer (B) are selected and used so as to obtain the structure of the repeating unit represented by the above-mentioned formula (5) of the polymer (B), respectively. do. That is, as the diamine component, a diamine having the structure of -N(Z)-Y ₅ -N(Z)- (the definitions of Y ₅ and Z are the same as above) is used, and as the tetracarboxylic acid derivative component, , a tetracarboxylic acid derivative having the structure of X ₅ (the definition of X ₅ is the same as above) is used.

Specific examples of the solvent for reacting the diamine component and the tetracarboxylic acid derivative component include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, N, Examples include N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, and 1,3-dimethyl-2-imidazolidinone. In addition, when the solvent solubility of the polymer is high, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, or the following formula [D-1] to formula [D A solvent represented by -3] can be used.

[Formula 35]

(In formula [D-1], D ¹ represents an alkyl group having 1 to 3 carbon atoms, in formula [D-2], D ² represents an alkyl group having 1 to 3 carbon atoms, and in formula [D-3], D ³ represents an alkyl group having 1 to 4 carbon atoms)

These solvents may be used individually or may be used in combination. In addition, even if it is a solvent that does not dissolve the polymer, it may be used by mixing with the solvent as long as the produced polymer does not precipitate.

When reacting the diamine component and the tetracarboxylic acid derivative component in a solvent, the reaction can be carried out at any concentration, but the concentration is preferably 1 to 50% by mass, more preferably 5 to 30% by mass. The reaction may be carried out at a high concentration at the beginning, and then the solvent may be added.

In the reaction, the ratio of the total number of moles of the diamine component and the total number of moles of the tetracarboxylic acid derivative component (total number of moles of the tetracarboxylic acid derivative component/total number of moles of the diamine component) is preferably 0.8 to 1.2. As in a typical condensation polymerization reaction, the closer this molar ratio is to 1.0, the larger the molecular weight of the produced polymer (A) and polymer (B) becomes.

Polyamic acid esters are, for example, [I] a method of reacting the polyamic acid obtained by the above method with an esterification agent, [II] a method of reacting tetracarboxylic acid diester and diamine, [III] tetracarboxylic acid diester. It can be obtained by known methods such as reacting a dihalide with a diamine.

Methods for obtaining polyimide include thermal imidization in which a solution containing polyimide precursors such as polyamic acid and polyamic acid ester obtained through the above reaction is heated as is, or catalytic imidization in which a catalyst is added to the solution. there is.

As for the polyimide in the polymer (A) of this invention, some or all of the repeating units of the polyimide precursor are ring-closed. In the above polyimide, the imidization rate is preferably 20 to 95%, preferably 30 to 95%, and more preferably 50 to 95%.

＜Solution viscosity/molecular weight of polymer＞

The polyamic acid, polyamic acid ester, and polyimide in the polymer (A) of the present invention have a solution viscosity of, for example, 10 to 1000 mPa·s when this is used as a solution with a concentration of 10 to 15% by mass. It is preferable from the viewpoint of sex, but is not particularly limited. In addition, the solution viscosity (mPa·s) of the polymer is 10 to 15 mass when prepared using a good solvent for the polymer (for example, γ-butyrolactone, N-methyl-2-pyrrolidone, etc.). This is the value measured at 25°C using an E-type rotational viscometer with respect to the % polymer solution.

The weight average molecular weight (Mw) of the polyamic acid, polyamic acid ester, and polyimide in terms of polystyrene measured by gel permeation chromatography (GPC) is preferably 1,000 to 500,000, and more preferably 2,000 to 300,000. . Moreover, the molecular weight distribution (Mw/Mn) expressed as the ratio between Mw and the number average molecular weight (Mn) in terms of polystyrene measured by GPC is preferably 15 or less, and more preferably 10 or less. By being within this molecular weight range, good orientation and stability of the liquid crystal display element can be ensured.

＜End sealant＞

When synthesizing the polymer (A) and polymer (B) in the present invention, an appropriate end-blocking agent may be used along with the above-mentioned tetracarboxylic acid derivative component and diamine component to form an end-blocked polymer. . The end-blocking polymer has the effect of improving the film hardness of the liquid crystal aligning film obtained by the coating film and improving the adhesion characteristics between the sealing agent and the liquid crystal aligning film.

Examples of the terminals of the polymer (A) and polymer (B) in the present invention include amino groups, carboxyl groups, acid anhydride groups, and derivatives thereof. The amino group, carboxyl group, acid anhydride group, and isocyanate group can be obtained by a normal condensation reaction, or by capping the ends using the following end capping agent, for example, using the following end capping agent, in the same manner. You can get it.

Examples of end capping agents include acetic anhydride, maleic anhydride, nadic anhydride, phthalic anhydride, itaconic anhydride, cyclohexanedicarboxylic anhydride, 3-hydroxyphthalic anhydride, trimellitic anhydride, 3-( 3-trimethoxysilyl)propyl)-3,4-dihydrofuran-2,5-dione, 4,5,6,7-tetrafluoroisobenzofuran-1,3-dione, 4-ethynylphthalic acid Acids such as anhydrides 1 Anhydride; Diester dicarbonate compounds such as di-tert-butyl dicarbonate and diallyl dicarbonate; Chlorocarbonyl compounds such as acryloyl chloride, methacryloyl chloride, and nicotinic acid chloride; Aniline, 2-aminophenol, 3-aminophenol, 4-aminosalicylic acid, 5-aminosalicylic acid, 6-aminosalicylic acid, 2-aminobenzoic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, cyclohexylamine, n-butylamine , monoamine compounds such as n-pentylamine, n-hexylamine, n-heptylamine, and n-octylamine; Monoisocyanate compounds such as isocyanates having unsaturated bonds such as ethyl isocyanate, phenyl isocyanate, naphthyl isocyanate, 2-acryloyloxyethyl isocyanate, and 2-methacryloyloxyethyl isocyanate; Isothiocyanate compounds, such as ethyl isothiocyanate and allyl isothiocyanate, are mentioned.

The usage ratio of the end capping agent is preferably 0.01 to 20 mol parts, and more preferably 0.01 to 10 mol parts, relative to a total of 100 mol parts of the diamine component to be used.

＜Liquid crystal alignment agent＞

The liquid crystal aligning agent of this invention contains a polymer (A) and, if necessary, a polymer (B). In addition to the polymer (A) and the polymer (B), the liquid crystal aligning agent of this invention may contain another polymer. Specific examples of other polymers include polysiloxane, polyester, polyamide, polyurea, polyurethane, polyorganosiloxane, cellulose derivative, polyacetal, polystyrene derivative, poly(styrene-maleic anhydride) copolymer, poly( A polymer selected from the group consisting of isobutylene-maleic anhydride) copolymer, poly(vinyl ether-maleic anhydride) copolymer, poly(styrene-phenylmaleimide) derivative, and poly(meth)acrylate. there is.

Specific examples of poly(styrene-maleic anhydride) copolymer include SMA1000, 2000, 3000 (manufactured by Cray Valley), GSM301 (manufactured by Gifu Shellac Manufacturing Company), etc., and poly(isobutylene-maleic acid) Specific examples of the anhydride) copolymer include Isovan-600 (manufactured by Kuraray Co., Ltd.), and specific examples of the poly(vinyl ether-maleic anhydride) copolymer include Gantrez AN-139 (methyl vinyl ether anhydride). Maleic acid resin, manufactured by Ashland Corporation) can be mentioned. Other polymers may be used individually by 1 type, or may be used in combination of 2 or more types. The content rate of other polymers is preferably 90 parts by mass or less, more preferably 10 to 90 parts by mass, and still more preferably 20 to 80 parts by mass with respect to a total of 100 parts by mass of the polymer contained in the liquid crystal aligning agent.

The liquid crystal aligning agent is used to produce a liquid crystal aligning film, and takes the form of a coating liquid from the viewpoint of forming a uniform thin film. Also in the liquid crystal aligning agent of this invention, it is preferable that it is a coating liquid containing the above-mentioned polymer component and an organic solvent. In that case, the concentration of the polymer in the liquid crystal aligning agent can be appropriately changed depending on the setting of the thickness of the coating film to be formed. From the point of view of forming a uniform and defect-free coating film, 1% by mass or more is preferable, and from the point of view of storage stability of the solution, 10% by mass or less is preferable. A particularly preferable polymer concentration is 2 to 8 mass%.

The organic solvent contained in the liquid crystal aligning agent is not particularly limited as long as the polymer component is dissolved uniformly. Specific examples include N,N-dimethylformamide, N,N-dimethylacetamide, N,N-dimethyllactamide, N,N-dimethylpropionamide, tetramethylurea, and N,N-diethylformamide. , N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethyl sulfoxide, γ-butyrolactone, γ-valerolactone, 1,3-dimethyl-2-imidazolidinone, Methyl ethyl ketone, cyclohexanone, cyclopentanone, 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, N-(n-propyl)-2-pyrroli Don, N-isopropyl-2-pyrrolidone, N-(n-butyl)-2-pyrrolidone, N-(tert-butyl)-2-pyrrolidone, N-(n-pentyl)-2 -Pyrrolidone, N-methoxypropyl-2-pyrrolidone, N-ethoxyethyl-2-pyrrolidone, N-methoxybutyl-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone Examples include money (they are also collectively referred to as “good solvents”). Among them, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide or γ -Butyrolactone is preferred. It is preferable that content of a good solvent is 20-99 mass % of the whole solvent contained in a liquid crystal aligning agent, it is more preferable that it is 20-90 mass %, and it is especially preferable that it is 30-80 mass %.

Moreover, as for the organic solvent contained in a liquid crystal aligning agent, in addition to the said solvent, it is preferable to use a mixed solvent using together the solvent (also called a poor solvent) which improves the coating property when applying a liquid crystal aligning agent and the surface smoothness of a coating film. do. 1-80 mass % of the whole solvent contained in a liquid crystal aligning agent is preferable, as for content of a poor solvent, 10-80 mass % is more preferable, and 20-70 mass % is especially preferable. The type and content of the poor solvent are appropriately selected depending on the coating device, application conditions, application environment, etc. of the liquid crystal aligning agent.

Specific examples of the poor solvent are given below, but are not limited to these.

Diisopropyl ether, diisobutyl ether, diisobutylcarbinol (2,6-dimethyl-4-heptanol), ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, 1,2-part Toxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, 4-hydroxy-4-methyl-2-pentanone, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, 3-ethoxybutyl acetate , 1-methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, ethylene glycol monoacetate, ethylene glycol diacetate, propylene carbonate, ethylene carbonate, ethylene glycol monobutyl ether, ethylene glycol monoisoamyl ether, ethylene glycol Monohexyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, 1-(2-butoxyethoxy)-2-propanol, 2-(2-butoxyethoxy)-1-propanol, propylene glycol monomethyl ether Acetate, propylene glycol diacetate, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monobutyl ether acetate, diethylene glycol monopropyl ether, diethylene glycol monoethyl ether acetate, di Ethylene glycol monobutyl ether acetate, 2-(2-ethoxyethoxy)ethyl acetate, diethylene glycol acetate, propylene glycol diacetate, n-butyl acetate, propylene glycol monoethyl ether acetate, cyclohexyl acetate, 4-methyl acetate -2-pentyl, 3-methoxymethyl propionate, 3-ethoxyethyl propionate, 3-methoxyethyl propionate, 3-methoxypropyl propionate, 3-methoxybutyl propionate, n-butyl lactate, isoamyl lactate, Diethylene glycol monoethyl ether, diisobutyl ketone (2,6-dimethyl-4-heptanone), etc. can be mentioned.

Poor solvents include, among others, diisobutylcarbinol, propylene glycol monobutyl ether, propylene glycol diacetate, diethylene glycol diethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, and 4-hydroxy- 4-methyl-2-pentanone, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, or diisobutyl ketone is preferred.

Preferred combinations of good solvents and poor solvents include N-methyl-2-pyrrolidone and ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone, and ethylene glycol monobutyl ether. , N-methyl-2-pyrrolidone, γ-butyrolactone and propylene glycol monobutyl ether, N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether, N-ethyl-2-pyrrolidone and 4 -Hydroxy-4-methyl-2-pentanone, N-ethyl-2-pyrrolidone and propylene glycol diacetate, N,N-dimethyllactamide and diisobutyl ketone, N-methyl-2-pyrrolidone and ethyl 3-ethoxypropionate, N-ethyl-2-pyrrolidone and ethyl 3-ethoxypropionate, N-methyl-2-pyrrolidone, ethyl 3-ethoxypropionate and dipropylene glycol monomethyl ether, N -Ethyl-2-pyrrolidone, ethyl 3-ethoxypropionate, propylene glycol monobutyl ether, N-methyl-2-pyrrolidone, ethyl 3-ethoxypropionate, diethylene glycol monopropyl ether, N-ethyl- 2-pyrrolidone, ethyl 3-ethoxypropionate, diethylene glycol monopropyl ether, N-methyl-2-pyrrolidone, ethylene glycol monobutyl ether acetate, N-ethyl-2-pyrrolidone, and dipropylene glycol. Dimethyl ether, N,N-dimethyllactamide and ethylene glycol monobutyl ether, N,N-dimethyllactamide and propylene glycol diacetate, N-ethyl-2-pyrrolidone, diethylene glycol diethyl ether, N-ethyl -2-pyrrolidone, diethylene glycol monoethyl ether, butyl cellosolve acetate, N-methyl-2-pyrrolidone, diethylene glycol monomethyl ether, butyl cellosolve acetate, N,N-dimethyllactamide and diethylene glycol diethyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone, 4-hydroxy-4-methyl-2-pentanone, diethylene glycol diethyl ether, N-ethyl-2- Pyrrolidone and N-methyl-2-pyrrolidone and 4-hydroxy-4-methyl-2-pentanone, N-ethyl-2-pyrrolidone and 4-hydroxy-4-methyl-2-pentanone Paddy and propylene glycol monobutyl ether, N-methyl-2-pyrrolidone and 4-hydroxy-4-methyl-2-pentanone and diisobutyl ketone, N-methyl-2-pyrrolidone and 4-hydroxy- 4-methyl-2-pentanone and dipropylene glycol monomethyl ether, N-methyl-2-pyrrolidone and 4-hydroxy-4-methyl-2-pentanone and propylene glycol monobutyl ether, N-methyl-2- Pyrrolidone, 4-hydroxy-4-methyl-2-pentanone, propylene glycol diacetate, N-ethyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone, and dipropylene glycol dimethyl ether. , γ-butyrolactone, 4-hydroxy-4-methyl-2-pentanone, diisobutyl ketone, γ-butyrolactone, 4-hydroxy-4-methyl-2-pentanone, propylene glycol diacetate, N -Methyl-2-pyrrolidone, γ-butyrolactone, propylene glycol monobutyl ether, diisobutyl ketone, N-methyl-2-pyrrolidone, γ-butyrolactone, propylene glycol monobutyl ether, and diiso Propyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone, propylene glycol monobutyl ether, diisobutylcarbinol, N-methyl-2-pyrrolidone, γ-butyrolactone, and dipropylene glycol. Dimethyl ether, N-methyl-2-pyrrolidone, propylene glycol monobutyl ether, dipropylene glycol dimethyl ether, N-ethyl-2-pyrrolidone, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, N- Ethyl-2-pyrrolidone, diethylene glycol diethyl ether, dipropylene glycol monomethyl ether, N-ethyl-2-pyrrolidone, propylene glycol monobutyl ether, propylene glycol diacetate, N-ethyl-2-p. Rolidone, propylene glycol monobutyl ether, diisobutyl ketone, N-ethyl-2-pyrrolidone, γ-butyrolactone, diisobutyl ketone, N-ethyl-2-pyrrolidone, and N,N-dimethyl. Lactone and diisobutyl ketone, N-methyl-2-pyrrolidone, ethylene glycol monobutyl ether and ethylene glycol monobutyl ether acetate, γ-butyrolactone, ethylene glycol monobutyl ether acetate and dipropylene glycol dimethyl ether, N -Ethyl-2-pyrrolidone, ethylene glycol monobutyl ether acetate, propylene glycol dimethyl ether, N-methyl-2-pyrrolidone, 4-methyl-2-pentyl acetate, ethylene glycol monobutyl ether, N-ethyl- 2-pyrrolidone, cyclohexyl acetate, diacetone alcohol cyclohexanone, propylene glycol monomethyl ether, cyclopentanone, propylene glycol monomethyl ether, N-methyl-2-pyrrolidone, cyclohexanone, propylene glycol monomethyl ether, etc. can be mentioned.

The liquid crystal aligning agent of this invention may further contain components (hereinafter also referred to as additive components) other than the polymer component and the organic solvent. Such additive components include adhesion aids to improve the adhesion between the liquid crystal alignment film and the substrate or between the liquid crystal alignment film and the sealant, compounds to increase the strength of the liquid crystal alignment film (hereinafter also referred to as crosslinking compounds), and compounds to promote imidization. compounds, dielectrics and conductive materials for adjusting the dielectric constant or electrical resistance of the liquid crystal alignment film.

The crosslinkable compound includes an oxiranyl group, an oxetanyl group, a protected isocyanate group, a protected isothiocyanate group, and an oxazoline ring structure from the viewpoint of exhibiting good resistance to AC afterimages and highly improving film strength. A compound having at least one group selected from the group consisting of a group containing a Meldrum acid structure, a cyclocarbonate group, and a group represented by the formula (d) below, or a compound represented by the formula (e) below. You can.

[Formula 36]

In the formula (d), R ₂ and R ₃ each independently represent a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or “*-CH ₂ -OH”. In the formula (e), A represents a (m+n) valent organic group having an aromatic ring, R and R' each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and m is 1 to 6. , n is 0 to 4. The arbitrary hydrogen atom of the aromatic ring may be a halogen atom, an alkyl group with 1 to 10 carbon atoms, an alkenyl group with 2 to 10 carbon atoms, an alkoxy group with 1 to 10 carbon atoms, a fluoroalkyl group with 1 to 10 carbon atoms, or a C2 to 10 alkyl group. It may be substituted with a fluoroalkenyl group or a fluoroalkoxy group having 1 to 10 carbon atoms.

Specific examples of compounds having an oxylanyl group include two or more compounds, such as compounds described in [0037] of Japanese Patent Application Laid-Open No. Hei 10-338880 and compounds having a triazine ring in the skeleton described in WO 2017/170483. Compounds having an oxylanyl group can be mentioned. Among these, N,N,N',N'-tetraglycidyl-m-xylenediamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N' ,N'-tetraglycidyl-4,4'-diaminodiphenylmethane, N,N,N',N'-tetraglycidyl-p-phenylenediamine, formula (r-1) ~ ( It may be a compound containing a nitrogen atom, such as a compound represented by r-3).

[Formula 37]

Specific examples of compounds having an oxetanyl group include compounds having two or more oxetanyl groups described in [0170] to [0175] of WO2011/132751 publication.

Specific examples of compounds having a protected isocyanate group include compounds having two or more protected isocyanate groups described in [0046] to [0047] in Japanese Patent Application Laid-Open No. 2014-224978, and [0119] to [0120] in WO2015/141598. Compounds having three or more protected isocyanate groups as described in and the like may be mentioned, and compounds represented by the following formulas (bi-1) to (bi-3) may be used.

[Formula 38]

Specific examples of compounds having a protected isothiocyanate group include compounds having two or more protected isothiocyanate groups described in Japanese Patent Application Laid-Open No. 2016-200798.

Specific examples of compounds having a group containing an oxazoline ring structure include compounds containing two or more oxazoline ring structures described in [0115] of Japanese Patent Application Laid-Open No. 2007-286597.

Specific examples of compounds having a group containing a Meldrum acid structure include compounds having two or more Meldrum acid structures described in WO2012/091088 publication.

Specific examples of compounds having a cyclocarbonate group include compounds described in WO2011/155577.

Examples of the alkyl group having 1 to 3 carbon atoms for R ₂ and R ₃ of the group represented by the formula (d) include methyl group, ethyl group, propyl group, and isopropyl group.

Specific examples of compounds having a group represented by the formula (d) include compounds having two or more groups represented by the formula (d) described in WO2015/072554 or Japanese Patent Application Laid-open No. 2016-118753. , compounds described in Japanese Patent Application Laid-Open No. 2016-200798, and the like, and may be compounds represented by the following formulas (hd-1) to (hd-8).

[Formula 39]

The (m+n) valent organic group having an aromatic ring in A of the above formula (e) is a (m+n) valent aromatic hydrocarbon group with 6 to 30 carbon atoms, or an aromatic hydrocarbon group with 6 to 30 carbon atoms bonded directly or through a linking group. Examples include a (m+n) valent organic group and a (m+n) valent group having an aromatic heterocyclic ring. Examples of the aromatic hydrocarbon group include benzene, naphthalene, and the like. Examples of the aromatic heterocycle include aromatic heterocycles represented by pyridine rings, among the structures exemplified in the nitrogen atom-containing heterocycles above. The linking group includes an alkylene group having 1 to 10 carbon atoms, -NR- (R is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms), or a group obtained by removing one hydrogen atom from the alkylene group, or divalent or trivalent cyclohexane. A ring, etc. may be mentioned. Additionally, any hydrogen atom of the alkylene group may be substituted with an organic group such as an alkyl group having 1 to 6 carbon atoms, a fluorine atom, or a trifluoromethyl group. Specific examples of the alkyl group having 1 to 5 carbon atoms for R and R' in the formula (e) include the alkyl groups exemplified for R ₁ to R ₄ in the formula (1).

Specific examples of the formula (e) include compounds described in WO2010/074269 and compounds represented by any of the following formulas (e-1) to (e-10).

[Formula 40]

The compounds exemplified above are examples of crosslinkable compounds and are not limited thereto. For example, those disclosed on pages 53 to 55 of publication WO2015/060357, etc. can be mentioned. Additionally, two or more types of crosslinkable compounds may be combined.

The content of the crosslinkable compound in the liquid crystal aligning agent of the present invention is preferably 0.5 to 20 parts by mass with respect to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent, the crosslinking reaction progresses, and further the AC afterimage From the viewpoint of exhibiting good resistance against radiation, the amount is more preferably 1 to 15 parts by mass.

Examples of the adhesion aid include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, 2-aminopropyltrimethoxysilane, and 2-aminopropyltri. Ethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-Ureidopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2- (3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3- Glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane , 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, tris-(trimethoxysilylpropyl)isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-mercapto Silane coupling agents such as propyltrimethoxysilane and 3-isocyanate propyltriethoxysilane can be mentioned.

When using a silane coupling agent, it is preferably 0.1 to 30 parts by mass, and more preferably 0.1 to 20 parts by mass, with respect to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent, from the viewpoint of expressing good resistance to AC afterimages. desirable.

Compounds for promoting the imidization include basic moieties (e.g., primary amino group, aliphatic heterocycle (e.g., pyrrolidine skeleton), aromatic heterocycle (e.g., imidazole ring, indole ring), or Compounds having an anidino group, etc.) (however, the crosslinking compound and adhesion aid are excluded), or compounds in which the basic moiety is generated during baking are preferable. More preferably, it is a compound in which the basic site is generated during firing, and specific examples include compounds represented by the following formulas (B-1) to (B-17). The content of the compound for promoting imidization is preferably 2 mol or less, more preferably 1 mol or less, and still more preferably 0.5 mol per 1 mol of amic acid or amic acid ester moiety of the polymer (A). A mole or less is good.

[Formula 41]

(D represents an organic group that is desorbed by heating, and is preferably either a tert-butoxycarbonyl group or a 9-fluorenylmethoxycarbonyl group. When there is a plurality of Ds, the plurality of Ds may be the same or different from each other. You can do it.)

The solid content concentration (the ratio that the total mass of components other than the solvent of the liquid crystal aligning agent accounts for to the total mass of the liquid crystal aligning agent) in the liquid crystal aligning agent of this invention is appropriately selected in consideration of viscosity, volatility, etc., but is preferably It is in the range of 1 to 10 mass%.

The range of a particularly preferable solid content concentration varies depending on the method used when applying the liquid crystal aligning agent to the substrate. As described in the process (1) described later, examples of the method for applying the liquid crystal aligning agent to the substrate include the roll coater method, spin coat method, printing method, and inkjet method. When using the roll coater method, it is particularly preferable that the solid content concentration is in the range of 4 to 10 mass%. When using the spin coating method, it is particularly preferable that the solid content concentration is in the range of 1.5 to 4.5 mass%. In the case of using the printing method, it is particularly preferable to set the solid content concentration in the range of 3 to 9% by mass and thereby set the solution viscosity in the range of 12 to 50 mPa·s. In the case of using the inkjet method, it is particularly preferable to set the solid content concentration in the range of 1 to 5% by mass, thereby setting the solution viscosity in the range of 3 to 15 mPa·s. The temperature when preparing the polymer composition is preferably 10 to 50°C, more preferably 20 to 30°C.

＜Liquid crystal alignment film＞

The liquid crystal aligning film of this invention is obtained from the said liquid crystal aligning agent. The liquid crystal aligning film of the present invention can be used for a horizontally aligned or vertically aligned (VA type) liquid crystal aligning film, and is a liquid crystal aligning film that is particularly preferable for a horizontally aligned liquid crystal display element such as an IPS type or an FFS drive type. Additionally, it is preferably used as a liquid crystal alignment film for photo-alignment processing. In addition, it can be effectively applied to various technical uses, for example, liquid crystal alignment films other than the above applications (liquid crystal alignment films for retardation films, liquid crystal alignment films for scanning antennas or liquid crystal array antennas, or liquid crystal alignment films for transmission and scattering type liquid crystal light control elements) ), or for other purposes, such as protective films (e.g. protective films for color filters), spacer films, interlayer insulating films, anti-reflective films, wiring coating films, anti-static films, motor insulating films (gate insulating films in flexible displays), etc. It can be applied.

The liquid crystal aligning film of this invention can be manufactured by the following processes (1)-(3), for example, Preferably, a method includes processes (1)-(4).

＜Step (1): Step of applying a liquid crystal alignment agent on a substrate＞

The liquid crystal aligning agent of the present invention is applied to one surface of the substrate on which the patterned transparent conductive film is formed by an appropriate coating method such as, for example, a roll coater method, a spin coat method, a printing method, or an inkjet method. Here, the substrate is not particularly limited as long as it is a substrate with high transparency. In addition to a glass substrate and a silicon nitride substrate, a plastic substrate such as an acrylic substrate or a polycarbonate substrate can also be used. In addition, in a reflective liquid crystal display element, an opaque material such as a silicon wafer can be used as long as it is only one side of the substrate, and a light-reflecting material such as aluminum can also be used for the electrode in this case. In addition, when manufacturing a liquid crystal display element of the IPS driving method or the FFS driving method, a substrate on which an electrode made of a transparent conductive film or metal film patterned in a comb shape is formed and a counter substrate on which no electrode is formed are used. do.

Methods for applying a liquid crystal aligning agent to a substrate and forming a film include screen printing, offset printing, flexographic printing, an inkjet method, or a spray method. Among them, a method of applying and forming a film by an inkjet method can be preferably used.

<Step (2): Process of baking the applied liquid crystal aligning agent>

Process (2) is a process of baking the liquid crystal aligning agent apply|coated on a board|substrate and forming a film|membrane. After applying the liquid crystal aligning agent on the substrate, the solvent is evaporated using a heating means such as a hot plate, a thermal circulation oven, or an IR (infrared) oven, or the polyamic acid or polyamic acid ester is thermally imidized. can be carried out or done. The drying and baking steps after applying the liquid crystal aligning agent of the present invention can be selected at any temperature and time, and may be performed multiple times. The calcination temperature can be, for example, 40 to 180°C. From the viewpoint of shortening the process, it may be carried out at 40 to 150°C. The firing time is not particularly limited, but is 1 to 10 minutes, preferably 1 to 5 minutes. When performing thermal imidization of polyamic acid or polyamic acid ester, the process of baking can be performed after the said baking process in the temperature range of, for example, 150-300 degreeC, Preferably it is 150-250 degreeC. The firing time is not particularly limited, but is 5 to 40 minutes, preferably 5 to 30 minutes.

Since the reliability of the liquid crystal display element may decrease if the film-like material after baking is too thin, the thickness is preferably 5 to 300 nm, and 10 to 200 nm is more preferable.

<Step (3): Process of performing orientation treatment on the film obtained in step (2)>

Step (3) is a step of subjecting the film obtained in step (2) to an orientation treatment, if necessary. That is, in horizontal alignment type liquid crystal display elements such as IPS drive type or FFS drive type, orientation ability imparting treatment is performed on the coating film. On the other hand, in a liquid crystal display element of a vertical alignment type such as VA mode or PSA mode, the formed coating film can be used as a liquid crystal alignment film as is, but the coating film may be subjected to an orientation ability imparting treatment. Examples of the alignment treatment method for the liquid crystal alignment film include a rubbing treatment method and a photo-alignment treatment method, and the photo-alignment treatment method is more preferable. In the photo-alignment treatment method, radiation deflected in a certain direction is irradiated on the surface of the film-like material, and in some cases, heat treatment is preferably performed at a temperature of 150 to 250 ° C. to achieve liquid crystal orientation (also referred to as liquid crystal orientation ability). One possible method is to grant a . As radiation, ultraviolet rays or visible rays having a wavelength of 100 to 800 nm can be used. Among these, ultraviolet rays have a wavelength of preferably 100 to 400 nm, and more preferably 200 to 400 nm.

The radiation dose is preferably 1 to 10,000 mJ/cm ² , more preferably 100 to 5,000 mJ/cm ² , more preferably 100 to 1,500 mJ/cm ² , and particularly preferably 100 to 1,000 mJ/cm ² And 100 to 400 mJ/cm ² is even more preferable. Conventionally, when a liquid crystal aligning agent is used, the amount of light irradiation in an orientation process is 100-5,000 mJ/cm ^<2> , but in the liquid crystal aligning agent of this invention, even if the amount of light irradiation in an orientation process is reduced, a liquid crystal aligning film A liquid crystal alignment film in which the variation (nonuniformity) of the liquid crystal orientation within the plane is suppressed can be obtained.

Moreover, when irradiating radiation, in order to improve liquid crystal orientation, you may irradiate the board|substrate with the said film-like substance while heating at 50-250 degreeC. The liquid crystal alignment film produced in this way can stably orientate liquid crystal molecules in a certain direction.

Moreover, by the above-mentioned method, the liquid crystal alignment film irradiated with polarized radiation can be contact-treated using water or a solvent, or the liquid crystal alignment film irradiated with radiation can be heat-processed.

The solvent used in the contact treatment is not particularly limited as long as it is a solvent that dissolves decomposition products generated from film-like substances by radiation irradiation. Specific examples include water, methanol, ethanol, 2-propanol, acetone, methyl ethyl ketone, 1-methoxy-2-propanol, 1-methoxy-2-propanol acetate, butyl cellosolve, ethyl lactate, and methyl lactate. , diacetone alcohol, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propyl acetate, butyl acetate, cyclohexyl acetate, etc. Among them, water, 2-propanol, 1-methoxy-2-propanol, or ethyl lactate are preferred in terms of versatility and solvent safety. More preferred are water, 1-methoxy-2-propanol, or ethyl lactate. The number of solvents may be one, or two or more types may be combined.

<Step (4): A step of heat treatment at 50 to 300°C on the film aligned in step (3)>

Heat treatment may be performed on the coating film irradiated with the above radiation. The temperature of this heat treatment is preferably 50 to 300°C, and more preferably 120 to 250°C. The heat treatment time is preferably 1 to 30 minutes, respectively.

＜Liquid crystal display device＞

The liquid crystal display element of this invention is equipped with the liquid crystal aligning film of this invention, and is manufactured as follows. Two substrates on which the liquid crystal alignment film obtained as described above was formed are prepared, and the liquid crystal is disposed between the two substrates arranged to face each other. Specifically, there are two methods listed below.

In the first method, two substrates are first arranged to face each other through a gap (cell gap) so that each liquid crystal alignment film faces each other. Next, the peripheral portions of the two substrates are bonded together using a sealant, and the liquid crystal composition is filled into the substrate surface and the cell gap defined by the sealant through the injection hole, brought into contact with the film surface, and then injected. Seal the hole.

The second method is called the ODF (One Drop Fill) method. For example, an ultraviolet light-curable sealant is applied to a predetermined location on one of the two substrates on which the liquid crystal alignment film is formed, and the liquid crystal composition is further dropped at several predetermined points on the surface of the liquid crystal alignment film. After that, the other substrate is bonded so that the liquid crystal alignment films face each other, and the liquid crystal composition is pressed and spread over the entire surface of the substrate and brought into contact with the film surface. Next, ultraviolet light is irradiated to the entire surface of the substrate to cure the sealant.

In the case of any of the above methods, it is further preferable to remove the flow orientation during liquid crystal charging by heating the used liquid crystal composition to a temperature at which it assumes an isotropic phase and then slowly cooling it to room temperature.

In addition, when the rubbing treatment is performed on the coating film, the two substrates are arranged to face each other so that the rubbing direction in each coating film is at a predetermined angle, for example, perpendicular or anti-parallel.

As the sealant, for example, an epoxy resin containing a curing agent and aluminum oxide spheres as a spacer can be used. Liquid crystals include nematic liquid crystals and smectic liquid crystals, and among them, nematic liquid crystals are preferable.

There is no particular limitation on the liquid crystal composition, and various liquid crystal compositions containing at least one type of liquid crystal compound (liquid crystal molecule) and having positive or negative dielectric anisotropy can be used. In addition, hereinafter, a liquid crystal composition having a positive dielectric anisotropy is also referred to as a positive liquid crystal, and a liquid crystal composition having a negative dielectric anisotropy is also referred to as a negative liquid crystal.

Liquid crystal compositions include liquid crystal compositions that exhibit a nematic phase, liquid crystal compositions that exhibit a smetic phase, and liquid crystal compositions that exhibit a cholesteric phase, and among these, liquid crystal compositions that exhibit a nematic phase are preferable.

The liquid crystal composition includes a fluorine atom, a hydroxy group, an amino group, a fluorine atom-containing group (e.g., trifluoromethyl group), a cyano group, an alkyl group, an alkoxy group, an alkenyl group, an isothiocyanate group, a heterocycle, and a cyclo It may contain a liquid crystal compound having an alkane, cycloalkene, steroid skeleton, benzene ring, or naphthalene ring, and may be a compound having two or more rigid moieties (mesogenic skeleton) in the molecule that exhibit liquid crystallinity (for example, a rigid It may also contain a bimesogenic compound in which two biphenyl structures or terphenyl structures are linked to an alkyl group.

The liquid crystal composition may further contain additives from the viewpoint of improving liquid crystal orientation. These additives include photopolymerizable monomers such as compounds having a polymerizable group; Optically active compounds (e.g., S-811 manufactured by Merck & Co., Ltd., etc.); Antioxidants; UV absorber; pigment; Antifoaming agent; A polymerization initiator or a polymerization inhibitor, etc. can be mentioned.

Positive liquid crystals include ZLI-2293, ZLI-4792, MLC-2003, MLC-2041, MLC-3019, or MLC-7081 manufactured by Merck & Co., Ltd.

Examples of negative liquid crystal include MLC-6608, MLC-6609, MLC-6610, or MLC-7026-100 manufactured by Merck & Co., Ltd.

Additionally, as a liquid crystal containing a compound having a polymerizable group, MLC-3023 manufactured by Merck & Co., Ltd. can be mentioned.

And, if necessary, a liquid crystal display element can be obtained by bonding a polarizing plate to the outer surface of the liquid crystal cell. Examples of the polarizing plate bonded to the outer surface of the liquid crystal cell include a polarizing plate in which a polarizing film called an "H film" in which iodine is absorbed while stretching polyvinyl alcohol is stretched and oriented is sandwiched between a cellulose acetate protective film, or a polarizing plate consisting of the H film itself. You can.

The IPS substrate, which is a comb electrode substrate used in the IPS system (mode), has a base material, a plurality of linear electrodes formed on the base material and arranged in a comb shape, and a liquid crystal alignment film formed on the base material so as to cover the linear electrodes. .

In addition, the FFS substrate, which is a comb electrode substrate used in the FFS system (mode), includes a base material, a surface electrode formed on the base material, an insulating film formed on the surface electrode, and a plurality of cells formed on the insulating film and arranged in a comb shape. It has a liquid crystal alignment film formed on a linear electrode and an insulating film so as to cover the linear electrode.

1 is a schematic cross-sectional view showing an example of an IPS mode transverse electric field liquid crystal display element provided with a liquid crystal aligning film obtained from the liquid crystal aligning agent of the present invention.

In the transverse electric field liquid crystal display element 1 illustrated in FIG. 1, between the comb electrode substrate 2 provided with the liquid crystal aligning film 2c and the opposing substrate 4 provided with the liquid crystal aligning film 4a, the liquid crystal 3 ) is narrowed down. The comb electrode substrate 2 includes a base material 2a, a plurality of linear electrodes 2b arranged in a comb shape, formed on the base material 2a, and covering the linear electrodes 2b on the base material 2a. It has a liquid crystal alignment film (2c) formed as follows. The opposing substrate 4 has a base material 4b and a liquid crystal aligning film 4a formed on the base material 4b. The liquid crystal aligning film (2c) is the liquid crystal aligning film of this invention. The liquid crystal aligning film 4c is also a liquid crystal aligning film of the present invention.

In the transverse electric field liquid crystal display element 1 of FIG. 1, when a voltage is applied to the linear electrodes 2b, an electric field is generated between the linear electrodes 2b as indicated by the electric field line L.

FIG. 2 is a schematic cross-sectional view showing an example of a transverse electric field liquid crystal display element in FFS mode provided with a liquid crystal aligning film obtained from the liquid crystal aligning agent of the present invention.

In the transverse electric field liquid crystal display element 1 illustrated in FIG. 2, between the comb electrode substrate 2 provided with the liquid crystal aligning film 2h and the opposing substrate 4 provided with the liquid crystal aligning film 4a, the liquid crystal 3 ) is narrowed down. The comb electrode substrate 2 is formed on a base material 2d, a surface electrode 2e formed on the base material 2d, an insulating film 2f formed on the surface electrode 2e, and the insulating film 2f. It has a plurality of linear electrodes 2g arranged in a comb shape, and a liquid crystal alignment film 2h formed on an insulating film 2f so as to cover the linear electrodes 2g. The opposing substrate 4 has a base material 4b and a liquid crystal aligning film 4a formed on the base material 4b. Liquid crystal aligning film (2h) is the liquid crystal aligning film of this invention. The liquid crystal aligning film 4a is also a liquid crystal aligning film of the present invention.

In the transverse electric field liquid crystal display element 1 of FIG. 2, when a voltage is applied to the surface electrode 2e and the linear electrode 2g, the surface electrode 2e and the linear electrode 2g, as indicated by the electric field line L, An electric field occurs between them.

Example

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these. The abbreviations of the compounds and the measurement methods for each characteristic are as follows.

Boc: tert-butoxycarbonyl group

Fmoc: 9-fluorenylmethyloxycarbonyl group

(specific diamines)

[Formula 42]

(Other diamines)

[Formula 43]

(Tetracarboxylic dianhydride)

[Formula 44]

(additive)

[Formula 45]

(menstruum)

NMP: N-methyl-2-pyrrolidone

BCS: Ethylene glycol monobutyl ether

(Measurement of molecular weight)

Using a room temperature gel permeation chromatography (GPC) device (GPC-101) (manufactured by Showa Denko) and columns (KD-803, KD-805) (manufactured by Showa Denko), molecular weight was measured under the following conditions. did.

Column temperature: 50℃

Eluent: N,N-dimethylformamide (as additives, lithium bromide monohydrate (LiBr·H ₂ O) is 30 mmol/L (liter), phosphoric acid/anhydrous crystal (o-phosphoric acid) is 30 mmol/L, tetrahydro Furan (THF) 10 mL/L)

Flow rate: 1.0 ml/min

Standard samples for creating a calibration curve: TSK standard polyethylene oxide (molecular weight: approximately 900,000, 150,000, 100,000, and 30,000) (manufactured by Tosoh Corporation) and polyethylene glycol (molecular weight: approximately 12,000, 4,000, and 1,000) (manufactured by Polymer Laboratories).

(Measurement of viscosity)

It was measured at a temperature of 25°C using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.), a sample volume of 1.1 mL, and a cone rotor TE-1 (1°34', R24).

＜Synthesis of polymer＞

(Synthesis Example 1)

In a 100 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, A1 (0.811 g, 7.50 mmol), WA-1 (1.02 g, 7.50 mmol), A2 (2.20 g, 9.00 mmol), A4 (2.39 g, 6.00 mmol), B1 (6.39 g, 28.5 mmol), and NMP (93.9 g) were added and stirred at 40°C for 20 hours to obtain a solution of polyamic acid (A-1) with a solid content concentration of 12% by mass (viscosity: 401 mPa). ·s) was obtained. The number average molecular weight (Mn) of this polyamic acid was 12,939 and the weight average molecular weight (Mw) was 38,921.

(Synthesis Example 2)

WA-1 (2.04 g, 15.0 mmol), A2 (2.20 g, 9.00 mmol), A4 (2.39 g, 6.00 mmol), B1 (6.39 g, 28.5 mmol) and NMP (95.5 g) were added and stirred at 40°C for 20 hours to obtain a solution (viscosity: 373 mPa·s) of polyamic acid (A-2) with a solid content concentration of 12% by mass. The Mn of this polyamic acid was 11,813 and the Mw was 37,191.

(Synthesis Example 3)

In a 100 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, A1 (0.811 g, 7.50 mmol), WA-2 (0.946 g, 7.50 mmol), A2 (2.20 g, 9.00 mmol), A4 (2.39 g, 6.00 mmol), B1 (6.46 g, 28.8 mmol), and NMP (93.9 g) were added and stirred at 40°C for 20 hours to obtain a solution of polyamic acid (A-3) with a solid content concentration of 12% by mass (viscosity: 399 mPa). ·s) was obtained. The Mn of this polyamic acid was 12,191 and the Mw was 38,811.

(Synthesis Example 4)

WA-2 (1.89 g, 15.0 mmol), A2 (2.20 g, 9.00 mmol), A4 (2.39 g, 6.00 mmol), B1 (6.46 g, 28.8 mmol) and NMP (94.9 g) were added and stirred at 40°C for 20 hours to obtain a solution (viscosity: 369 mPa·s) of polyamic acid (A-4) with a solid content concentration of 12% by mass. The Mn of this polyamic acid was 11,304 and the Mw was 37,191.

(Synthesis Example 5)

In a 100 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, A1 (0.811 g, 7.50 mmol), WA-3 (1.04 g, 7.50 mmol), A2 (2.20 g, 9.00 mmol), A4 (2.39 g, 6.00 mmol), B1 (6.39 g, 28.5 mmol), and NMP (94.1 g) were added and stirred at 40°C for 20 hours to obtain a solution of polyamic acid (A-5) with a solid content concentration of 12% by mass (viscosity: 372 mPa). ·s) was obtained. The Mn of this polyamic acid was 12,492 and the Mw was 40,113.

(Synthesis Example 6)

WA-3 (2.07 g, 15.0 mmol), A2 (2.20 g, 9.00 mmol), A4 (2.39 g, 6.00 mmol), B1 (6.39 g, 28.5 mmol) and NMP (95.7 g) were added and stirred at 40°C for 20 hours to obtain a solution (viscosity: 385 mPa·s) of polyamic acid (A-6) with a solid content concentration of 12% by mass. The Mn of this polyamic acid was 13,012 and the Mw was 40,200.

(Synthesis Example 7)

In a 100 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, A1 (0.811 g, 7.50 mmol), WA-4 (1.26 g, 7.50 mmol), A2 (2.20 g, 9.00 mmol), A4 (2.39 g, 6.00 mmol), B1 (6.39 g, 28.5 mmol), and NMP (95.7 g) were added and stirred at 40°C for 20 hours to obtain a solution of polyamic acid (A-7) with a solid content concentration of 12% by mass (viscosity: 370 mPa). ·s) was obtained. The Mn of this polyamic acid was 11,028 and the Mw was 37,190.

(Synthesis Example 8)

WA-4 (2.52 g, 15.0 mmol), A2 (2.20 g, 9.00 mmol), A4 (2.39 g, 6.00 mmol), B1 (6.39 g, 28.5 mmol) and NMP (99.0 g) were added and stirred at 40°C for 20 hours to obtain a solution (viscosity: 360 mPa·s) of polyamic acid (A-8) with a solid content concentration of 12% by mass. The Mn of this polyamic acid was 10,221 and the Mw was 36,821.

(Synthesis Example 9)

In a 100 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, A1 (0.487 g, 4.50 mmol), WA-1 (0.613 g, 4.50 mmol), A2 (2.20 g, 9.00 mmol), A4 (2.39 g, 6.00 mmol), A3 (1.92 g, 6.00 mmol), B1 (6.42 g, 28.7 mmol) and NMP (102 g) were added and stirred at 40°C for 20 hours to obtain a polyamic acid (A- 9) A solution (viscosity: 409 mPa·s) was obtained. The Mn of this polyamic acid was 13,001 and the Mw was 40,012.

(Synthesis Example 10)

WA-1 (1.23 g, 9.00 mmol), A2 (2.20 g, 9.00 mmol), A4 (2.39 g, 6.00 mmol), A3 (1.92 g, 6.00 mmol), B1 (6.46 g, 28.8 mmol), and NMP (104 g) were added and stirred at 40°C for 20 hours to obtain a solution of polyamic acid (A-10) with a solid content concentration of 12% by mass (viscosity: 415 mPa). ·s) was obtained. The Mn of this polyamic acid was 12,948 and the Mw was 40,889.

(Synthesis Example 11)

In a 100 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, A1 (0.487 g, 4.50 mmol), WA-3 (0.622 g, 4.50 mmol), A2 (2.20 g, 9.00 mmol), A4 (2.39 g, 6.00 mmol), A3 (1.92 g, 6.00 mmol), B1 (6.42 g, 28.7 mmol) and NMP (102 g) were added and stirred at 40°C for 20 hours to obtain a polyamic acid (A- 11) A solution (viscosity: 419 mPa·s) was obtained. The Mn of this polyamic acid was 12,978 and the Mw was 41,048.

(Synthesis Example 12)

WA-3 (1.24 g, 9.00 mmol), A2 (2.20 g, 9.00 mmol), A4 (2.39 g, 6.00 mmol), A3 (1.92 g, 6.00 mmol), B1 (6.42 g, 28.7 mmol) and NMP (103 g) were added and stirred at 40°C for 20 hours to obtain a solution of polyamic acid (A-12) with a solid content concentration of 12% by mass (viscosity: 401 mPa). ·s) was obtained. The Mn of this polyamic acid was 11,992 and the Mw was 39,171.

(Synthesis Example 13)

In a 100 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, A1 (0.487 g, 4.50 mmol), WA-4 (0.757 g, 4.50 mmol), A2 (2.20 g, 9.00 mmol), A4 (2.39 g) , 6.00 mmol), A3 (1.92 g, 6.00 mmol), B1 (6.39 g, 28.5 mmol) and NMP (103 g) were added and stirred at 40°C for 20 hours to obtain a polyamic acid (A) with a solid content concentration of 12% by mass. -13) solution (viscosity: 398 mPa·s) was obtained. The Mn of this polyamic acid was 12,091 and the Mw was 42,039.

(Synthesis Example 14)

WA-4 (1.51 g, 9.00 mmol), A2 (2.20 g, 9.00 mmol), A4 (2.39 g, 6.00 mmol), A3 (1.92 g, 6.00 mmol), B1 (6.39 g, 28.5 mmol), and NMP (103 g) were added and stirred at 40°C for 20 hours to obtain a solution of polyamic acid (A-14) with a solid content concentration of 12% by mass (viscosity: 366 mPa). ·s) was obtained. The Mn of this polyamic acid was 10,208 and the Mw was 35,029.

(Synthesis Example 15)

Add A6 (4.78 g, 24.0 mmol), A1 (0.649 g, 6.00 mmol), B2 (5.59 g, 28.5 mmol), and NMP (99.2 g) to a 100 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube. Then, by stirring at room temperature for 5 hours, a solution (viscosity: 200 mPa·s) of polyamic acid (A-15) with a solid content concentration of 10% by mass was obtained. The Mn of this polyamic acid was 14,101 and the Mw was 43,911.

(Synthesis Example 16)

Add A5 (5.37 g, 18.0 mmol), A1 (1.30 g, 12.0 mmol), B2 (5.41 g, 27.6 mmol), and NMP (68.5 g) to a 100 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube. Then, by stirring at room temperature for 5 hours, a solution (viscosity: 751 mPa·s) of polyamic acid (A-16) with a solid content concentration of 15% by mass was obtained. The Mn of this polyamic acid was 11,038 and the Mw was 37,102.

(Synthesis Example 17)

Add A5 (7.16 g, 24.0 mmol), A7 (1.19 g, 6.00 mmol), B2 (5.41 g, 27.6 mmol), and NMP (78.0 g) to a 100 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube. Then, by stirring at room temperature for 5 hours, a solution (viscosity: 761 mPa·s) of polyamic acid (A-17) with a solid content concentration of 15% by mass was obtained. The Mn of this polyamic acid was 10,951 and the Mw was 38,322.

(Synthesis Example 18 (Comparison))

In a 100 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, A1 (1.62 g, 15.0 mmol), A2 (2.20 g, 9.00 mmol), A4 (2.39 g, 6.00 mmol), B1 (6.39 g, 28.5 mmol) ) and NMP (92.4 g) were added and stirred at 40°C for 20 hours to obtain a solution of polyamic acid (RA-1).

<Preparation of liquid crystal aligning agent>

(Example 1)

NMP (9.33 g), BCS (4.00 g), and AD-2 (0.112 g) were added to the polyamic acid (A-1) solution (6.67 g) obtained in Synthesis Example 1, and stirred at room temperature for 2 hours. Liquid crystal aligning agent (V-1) was obtained.

(Examples 2 to 14)

Liquid crystal aligning agents (V-2) to (V-14) were obtained by operating in the same manner as in Example 1 except that the solution of the polyamic acid to be used was used as a solution of (A-2) to (A-14). .

(Example 15)

To the polyamic acid (A-9) solution (5.30 g) obtained in Synthesis Example 9, the polyamic acid (A-15) solution (9.54 g) obtained in Synthesis Example 15, NMP (3.78 g), BCS (9.00 g), AD The NMP 10 mass% diluted solution (0.800g) of -1 and the NMP 1 mass% diluted solution (1.59g) of AD-3 were added, it stirred at room temperature for 2 hours, and the liquid crystal aligning agent (V-15) was obtained.

(Example 16)

To the polyamic acid (A-10) solution (5.30 g) obtained in Synthesis Example 10, the polyamic acid (A-15) solution (9.54 g) obtained in Synthesis Example 15, NMP (3.78 g), BCS (9.00 g), AD The NMP 10 mass% diluted solution (0.800g) of -1 and the NMP 1 mass% diluted solution (1.59g) of AD-3 were added, it stirred at room temperature for 2 hours, and the liquid crystal aligning agent (V-16) was obtained.

(Example 17)

To the polyamic acid (A-9) solution (5.30 g) obtained in Synthesis Example 9, the polyamic acid (A-16) solution (6.36 g) obtained in Synthesis Example 16, NMP (6.96 g), BCS (9.00 g), AD The NMP 10 mass% diluted solution (0.800g) of -1 and the NMP 1 mass% diluted solution (1.59g) of AD-3 were added, it stirred at room temperature for 2 hours, and the liquid crystal aligning agent (V-17) was obtained.

(Example 18)

To the polyamic acid (A-9) solution (5.30 g) obtained in Synthesis Example 9, the polyamic acid (A-17) solution (6.36 g) obtained in Synthesis Example 17, NMP (6.96 g), BCS (9.00 g), AD The NMP 10 mass% diluted solution (0.800g) of -1 and the NMP 1 mass% diluted solution (1.59g) of AD-3 were added, it stirred at room temperature for 2 hours, and the liquid crystal aligning agent (V-18) was obtained.

(Example 19)

To the polyamic acid (A-10) solution (5.30 g) obtained in Synthesis Example 10, the polyamic acid (A-16) solution (6.36 g) obtained in Synthesis Example 16, NMP (6.96 g), BCS (9.00 g), AD The NMP 10 mass% diluted solution (0.800g) of -1 and the NMP 1 mass% diluted solution (1.59g) of AD-3 were added, it stirred at room temperature for 2 hours, and the liquid crystal aligning agent (V-19) was obtained.

(Example 20)

To the polyamic acid (A-10) solution (5.30 g) obtained in Synthesis Example 10, the polyamic acid (A-17) solution (6.36 g) obtained in Synthesis Example 17, NMP (6.96 g), BCS (9.00 g), AD The NMP 10 mass% diluted solution (0.800g) of -1 and the NMP 1 mass% diluted solution (1.59g) of AD-3 were added, it stirred at room temperature for 2 hours, and the liquid crystal aligning agent (V-20) was obtained.

(Comparative Example 1)

NMP (9.33 g) and BCS (4.00 g) were added to the polyamic acid (RA-1) solution (6.67 g) obtained in Synthesis Example 18, stirred at room temperature for 2 hours, and liquid crystal aligning agent (RV-1) was added. got it

(Comparative Example 2)

NMP (9.33 g), BCS (4.00 g), and AD-2 (0.112 g) were added to the polyamic acid (RA-1) solution (6.67 g) obtained in Synthesis Example 18, and stirred at room temperature for 2 hours. A liquid crystal aligning agent (RV-2) was obtained.

Using the liquid crystal aligning agent obtained above, an FFS drive liquid crystal cell was manufactured in the procedure shown below, and various evaluations were performed.

＜Configuration of FFS driven liquid crystal cell＞

A liquid crystal cell equipped with the configuration of an FFS mode liquid crystal display element was manufactured.

First, a substrate on which electrodes were formed was prepared. The substrate is a glass substrate having a rectangular shape of 30 mm x 50 mm and a thickness of 0.7 mm. On the substrate, an ITO electrode with a solid pattern constituting a counter electrode is formed as the first layer. On the counter electrode of the first layer, a SiN (silicon nitride) film formed as a second layer by a CVD (chemical vapor deposition) method is formed. The SiN film of the second layer has a film thickness of 300 nm and functions as an interlayer insulating film. On the SiN film of the second layer, a comb-shaped pixel electrode formed by patterning an ITO film as the third layer is disposed, forming two pixels, a first pixel and a second pixel. The size of each pixel is 10 mm vertically and 5 mm horizontally. At this time, the counter electrode of the first layer and the pixel electrode of the third layer are electrically insulated by the action of the SiN film of the second layer.

The pixel electrode of the third layer has a comb-tooth shape in which a plurality of electrode elements with a width of 3 μm bent at an inner angle of 160° at the center are arranged in parallel at intervals of 6 μm, and one pixel has a plurality of electrodes. It has a first area and a second area bordered by a line connecting the curved portion of the element.

Next, the liquid crystal aligning agent obtained above was filtered through a filter with a hole diameter of 1.0 μm, and then the prepared substrate with electrodes (first glass substrate) was prepared. Glass having a columnar spacer with a height of 4 μm and an ITO film formed on the back side was prepared. It was applied to the substrate (second glass substrate) by spin coating. After drying on an 80°C hot plate for 2 minutes, baking was performed in a 230°C hot air circulation oven for 30 minutes to form a coating film with a film thickness of 100 nm. The orientation treatment was performed by irradiating the irradiation amount shown in each table with linearly polarized ultraviolet rays with a wavelength of 254 nm at an extinction ratio of 26:1 through a polarizing plate to this coating film surface, and obtaining a substrate with a liquid crystal alignment film. In addition, the liquid crystal alignment film formed on the substrate with electrodes is aligned so that the direction dividing the inner angle of the pixel bending portion is perpendicular to the orientation direction of the liquid crystal, and the liquid crystal alignment film formed on the second glass substrate is prepared when the liquid crystal cell is manufactured. 1. Alignment treatment is performed so that the orientation direction of the liquid crystal on the glass substrate matches the orientation direction of the liquid crystal on the second glass substrate. The above two substrates were used as a set, a sealant (XN-1500T manufactured by Mitsui Chemicals) was printed on the substrate, and the other substrate was bonded with the liquid crystal alignment film surface facing at an orientation direction of 0°. After that, the sealant was cured to produce an empty cell. Liquid crystal MLC-3019 (manufactured by Merck & Co., Ltd.) was injected into this empty cell by a reduced-pressure injection method, the injection port was sealed, and an FFS driven liquid crystal cell was obtained. After that, the obtained liquid crystal cell was heated at 120°C for 1 hour, left to stand overnight, and then used for evaluation.

＜Evaluation of in-plane uniformity of contrast＞

Variation in the twist angle of the liquid crystal cell was evaluated using AxoStep manufactured by AXOMETRICS. The liquid crystal cell produced above was installed on a measurement stage, and the distribution of Circular Retardance within the pixel plane was measured in a state where no voltage was applied, and 3σ, which is three times the standard deviation (σ), was calculated. It can be said that the smaller the value of 3σ, the better the in-plane uniformity. As an evaluation standard, when the 3σ value was less than 1.00, it was considered “excellent,” when it was 1.00 or more and 1.15 or less, it was “good,” and when it was greater than 1.15, it was “bad.”

Table 3 shows the evaluation results performed on the liquid crystal display elements using each liquid crystal aligning agent of the above examples and comparative examples.

＜Stability evaluation of liquid crystal orientation＞

With respect to the FFS drive liquid crystal cell manufactured above, an alternating current voltage of ±5 V was applied at a frequency of 60 Hz for 120 hours in a constant temperature environment of 60°C. After that, the space between the pixel electrode and the opposing electrode of the liquid crystal cell was short-circuited, and the liquid was left at room temperature for one day. Regarding the liquid crystal cell that underwent the above treatment, the deviation between the orientation direction of the liquid crystal in the first area and the liquid crystal in the second area of the pixel in the state of no voltage application was calculated as an angle. Specifically, a liquid crystal cell is installed between two polarizing plates arranged so that the polarization axes are orthogonal, the backlight is turned on, the arrangement angle of the liquid crystal cell is adjusted so that the intensity of transmitted light in the first region of the pixel is minimal, and then the pixel The rotation angle required when the liquid crystal cell was rotated so that the intensity of the transmitted light in the second region was minimized was determined. It can be said that the stability of the liquid crystal orientation is better as the value of the rotation angle is smaller. As an evaluation standard, when it was 0.10 or less, it was considered “excellent,” when it was greater than 0.10 and less than 0.30, it was “good,” and when it was greater than 0.30, it was “poor.”

Table 3 shows the evaluation results performed on the liquid crystal display elements using each liquid crystal aligning agent of the above examples and comparative examples.

As can be seen from the above Table 3, the liquid crystal aligning film obtained from the liquid crystal aligning agent using specific diamine WA-1 to WA-4 is compared to the liquid crystal aligning film obtained from the liquid crystal aligning agent comprised from the diamine component which does not contain specific diamine. , over a wide range of light irradiation amounts, it exhibited at least one of the characteristics of high in-plane uniformity and high stability of liquid crystal orientation.

Industrial applicability

By using the liquid crystal aligning agent of this invention, the liquid crystal display element of an IPS drive type and an FFS drive type WHEREIN: A liquid crystal aligning film in which the afterimage generated by long-term alternating current drive was suppressed can be obtained. Therefore, use in liquid crystal display elements requiring high display quality can be expected. In addition, these elements are also useful in liquid crystal displays for display purposes, dimming windows and optical shutters that control the transmission and blocking of light.

In addition, the entire contents of the specification, claims, drawings and abstract of Japanese Patent Application No. 2021-022830 filed on February 16, 2021 are hereby cited and accepted as disclosure of the specification of the present invention.

1: Transverse electric field liquid crystal display device
2: Comb electrode substrate
2a: Description
2b: linear electrode
2c: liquid crystal alignment film
2d: base material
2e: cotton electrode
2f: insulating film
2g: linear electrode
2h: Liquid crystal alignment layer
3: liquid crystal
4: Opposite substrate
4a: Liquid crystal alignment layer
4b: Description
L: electric field lines

Claims (18)

Characterized by containing at least one type of polymer (A) selected from the group consisting of a polyimide precursor having a repeating unit (a1) represented by the following formula (1) and a polyimide that is an imidate of the polyimide precursor. Liquid crystal orientation agent.

(In formula (1), R ₁ to R ₄ each independently contain a hydrogen atom, a halogen atom, an alkyl group with 1 to 6 carbon atoms, an alkenyl group with 2 to 6 carbon atoms, an alkynyl group with 2 to 6 carbon atoms, or a fluorine atom. represents a monovalent organic group having 1 to 6 carbon atoms or a phenyl group, and at least one of R ₁ to R ₄ represents a group other than a hydrogen atom as defined above.
R and Z each independently represent a hydrogen atom or a monovalent organic group. Y ₁ represents a divalent organic group represented by the formula (H) below.)

(In formula (H), R _a represents a hydroxy group, a halogen atom, or a monovalent organic group having 1 to 3 carbon atoms. a is an integer of 1 to 4. In addition, when R _a is present in multiple numbers, Each may be the same or different. * indicates a bond.) According to claim 1,
The monovalent organic group in the formula (H) is an alkyl group, a halogenated alkyl group in which at least part of the hydrogen atoms on the alkyl group are substituted with halogen atoms, an alkoxy group, and a halogenated group in which at least part of the hydrogen atoms on the alkoxy group are substituted with halogen atoms. A liquid crystal aligning agent that is an alkoxy group or an alkenyl group. The method of claim 1 or 2,
A liquid crystal aligning agent in which the divalent organic group represented by the formula (H) is a divalent organic group represented by any of the following formulas (h-1) to (h-16).

(In formulas (h-1) to (h-16), * represents a bond) The method according to any one of claims 1 to 3,
The polymer (A) is at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a2) represented by the following formula (2) and a polyimide that is an imidate of the polyimide precursor. , liquid crystal aligning agent.

(In formula (2), R ₁ to R ₄ , R and Z have the same meaning as in the case of formula (1) above. Y ₂ represents a divalent organic group represented by the formula (O) below.)

(In formula (O), Ar each independently represents a benzene ring, a biphenyl structure, or a naphthalene ring. Any hydrogen atom on the ring of Ar may be substituted with a halogen atom or a monovalent organic group. Q ₂ is -(CH ₂ ) _n - (n is 2 to 18), or a part of -(CH ₂ ) _n - among -O-, -C(=O)- and -OC(=O)- Indicates which group is substituted. * indicates the bonding hand.) According to claim 4,
A liquid crystal aligning agent in which the divalent organic group represented by the formula (O) is a divalent organic group represented by any of the following formulas (o-1) to (o-14).

(In formulas (o-1) to (o-14), * represents a bond. In formula (o-14), the two m are each independent.) The method according to any one of claims 1 to 5,
A polyimide precursor in which the polymer (A) further has at least one selected from the group consisting of a repeating unit (a2') represented by the following formula (2') and a repeating unit (a3) represented by the following formula (3) And a liquid crystal aligning agent which is at least 1 type of polymer selected from the group which consists of polyimide which is an imidate of this polyimide precursor.

₍ In formulas (2' ₎ and (3), X _{2 '} and D) - (D represents a carbamate-based protecting group)" represents a divalent organic group having 6 to 30 carbon atoms in the molecule. R and Z have the same meaning as in the above formula (1).)

(In the formula (O2), m is an integer of 0 to 2, and Ar _2' represents an unsubstituted or substituted benzene ring. However, when m is 0, Ar _2' represents an unsubstituted benzene ring, and m When 1 or 2, Ar _2' each independently represents an unsubstituted benzene ring or a benzene ring in which any hydrogen atom on the benzene ring is substituted with a halogen atom or a monovalent organic group. Q _2' represents Represents a single bond or -O-. * Represents a bond. When multiple Ar _2' and Q _2' exist, they may be the same or different.) According to claim 6,
A liquid crystal aligning agent in which the divalent organic group represented by the above formula (O2) is a divalent organic group represented by any of the following formulas (o2-1) to (o2-12).

(In formulas (o2-1) to (o2-12), * represents a bond) The method according to any one of claims 1 to 7,
A liquid crystal aligning agent in which the polymer (A) contains the total of the repeating unit (a1) and the imidized structural units of the repeating unit (a1) in an amount of 10 to 95 mol% of all repeating units. According to any one of claims 2 to 8,
The liquid crystal aligning agent in which the said polymer (A) contains the total of the said repeating unit (a2) and the imidated structural unit of the said repeating unit (a2) in an amount of 10 to 90 mol% of all repeating units. According to claim 6,
Liquid crystal, wherein the polymer (A) contains the total of the repeating unit (a1), the repeating unit (a2), the repeating unit (a2'), and their imidized structural units in an amount of 30 mol% or more of the total repeating units. Orientation agent. The method according to any one of claims 1 to 10,
A liquid crystal aligning agent used in a liquid crystal aligning film for photo-alignment processing. A liquid crystal aligning film obtained from the liquid crystal aligning agent according to any one of claims 1 to 11. A liquid crystal display element comprising the liquid crystal alignment film according to claim 12. The manufacturing method of the liquid crystal alignment film for liquid crystal display elements containing the following processes (1) - (3).
Process (1): A process of applying the liquid crystal aligning agent according to any one of claims 1 to 11 on a substrate.
Process (2): Process of baking the applied liquid crystal aligning agent
Process (3): Process of subjecting the film obtained in process (2) to an orientation treatment as necessary. According to claim 14,
A method for producing a liquid crystal alignment film, wherein the alignment treatment is photo-alignment treatment. According to claim 15,
The manufacturing method of the liquid crystal alignment film whose radiation dose in the said photo-alignment process is 100-1,500 mJ/cm ^<2> . The method according to any one of claims 14 to 16,
The manufacturing method of a liquid crystal aligning film which further includes process (4) which heat-processes 50-300 degreeC with respect to the film|membrane orientation-processed in process (3). The method according to any one of claims 14 to 17,
A method of producing a liquid crystal alignment film, wherein the liquid crystal display element is an IPS drive type or FFS drive type liquid crystal display element.

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