KR20240082258A - Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display device - Google Patents

Abstract

(각 기호의 정의는 명세서에 기재된 바와 같다.)A liquid crystal aligning agent that expands the range of light irradiation from which a liquid crystal aligning film with a small deviation (non-uniformity) of the twist angle of the liquid crystal within the plane of the liquid crystal aligning film can be obtained, and is also used to obtain a liquid crystal aligning film that does not cause display unevenness resulting from the cleaning process. , a liquid crystal aligning agent that forms a liquid crystal aligning film with a high water contact angle, a liquid crystal aligning film obtained from the liquid crystal aligning agent, and a high-performance liquid crystal display element provided with the liquid crystal aligning film.
At least one type of polymer (P) selected from the group consisting of a polyimide precursor obtained using a diamine component containing diamine (0) represented by the following formula ( _DA ) and a polyimide that is an imidate of the polyimide precursor A liquid crystal aligning agent characterized by containing, a liquid crystal aligning film obtained from the liquid crystal aligning agent, and a liquid crystal display element having the liquid crystal aligning film.

(The definition of each symbol is as described in the specification.)

Description

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

This invention relates to a liquid crystal aligning agent, a liquid crystal aligning film obtained from the liquid crystal aligning agent, and a liquid crystal display element provided with the liquid crystal aligning film.

Liquid crystal display elements are used widely, from small applications such as mobile phones and smartphones to relatively large applications such as televisions and monitors. In addition, various driving methods with different electrode structures and physical properties of the liquid crystal molecules used have been developed, for example, TN (Twisted Nematic) method, STN (Super Twisted Nematic) method, VA (Vertical Alignment) method, IPS (In Liquid crystal display devices using various modes such as -Plane Switching (FFS) method and FFS (Fringe Field Switching) method are known. These liquid crystal display elements generally have a liquid crystal alignment film that is essential for controlling the alignment state of liquid crystal molecules. As materials for liquid crystal alignment films, polyamic acid and polyimide are generally used because they have good various characteristics such as heat resistance, mechanical strength, and affinity with liquid crystal.

Currently, the liquid crystal alignment film that is most widely used industrially is manufactured by performing a so-called rubbing alignment treatment in which the surface of a resin film such as polyimide formed on an electrode substrate is rubbed in one direction with a cloth such as cotton, nylon, or polyester. It is becoming. Rubbing orientation treatment is a useful method that is simple and highly productive. As an alignment treatment method that replaces the rubbing treatment, a photo-alignment treatment method that imparts liquid crystal alignment ability by irradiating polarized radiation is known. Photo-alignment treatment methods using photoisomerization reaction, photocrosslinking reaction, photodecomposition reaction, etc. have been proposed (for example, see Non-Patent Document 1, Patent Document 1, and Patent Document 2).

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

“Liquid Crystal Photo-Alignment Film”, Functional Materials, November 1997, Vol.17, No.11, pages 13 to 22

Recently, with the increase in performance of liquid crystal display elements, in addition to large-screen, high-definition liquid crystal televisions, application to automotive applications such as car navigation systems, meter panels, surveillance cameras, and medical camera monitors is being considered. Therefore, the demand for improved performance of liquid crystal display elements, especially high definition, is increasing, and liquid crystal alignment films are required to be able to further improve the various characteristics of liquid crystal display elements.

Additionally, as liquid crystal display elements become larger, a problem arises in which the twist angle of the liquid crystal within the plane of the liquid crystal display element slightly varies due to variations in the manufacturing process. This variation causes the brightness to become non-uniform within the plane when the liquid crystal display element is used for black display, which leads to lowering the quality of the liquid crystal display element.

In addition, in the rubbing alignment treatment or photo-alignment treatment, a cleaning process with a solvent may be performed after the alignment treatment in order to remove impurities. In this cleaning process, solvent cratering and droplet generation during air knife drying are generated, and the film surface is cleaned locally unevenly. In the resulting liquid crystal display element, display unevenness along the air knife direction is eliminated. There are times when it happens.

The present invention has been made in consideration of the above circumstances, and is a liquid crystal aligning agent that expands the range of light irradiation amount at which a liquid crystal aligning film with small deviation (non-uniformity) of the twist angle of the liquid crystal within the plane of the liquid crystal aligning film is obtained, and also results from the cleaning process. The purpose is to provide a liquid crystal aligning agent capable of forming a liquid crystal aligning film having a high water contact angle for obtaining a liquid crystal aligning film that does not cause display unevenness, and a liquid crystal display element provided with the liquid crystal aligning film.

As a result of intensive research in order to achieve the above-described problem, the present inventor found that a liquid crystal aligning agent containing a polymer using a diamine having a specific structure is effective for achieving the above-mentioned object, and completed the present invention.

The present invention relates to at least one polyimide precursor obtained by using a diamine component containing diamine (0) represented by the formula ( _DA ) below and a polyimide that is an imidate of the polyimide precursor. It is a liquid crystal aligning agent characterized by containing a polymer (P), a liquid crystal aligning film obtained from the liquid crystal aligning agent, and a liquid crystal display element having the liquid crystal aligning film.

[Formula 1]

(Ar represents a divalent aromatic group of any of a divalent benzene ring, biphenyl structure, or naphthalene ring, and any hydrogen atom on the benzene ring, biphenyl structure, or naphthalene ring may be substituted with a monovalent group. m , n are each independently integers from 1 to 3.

Any hydrogen atom on the benzene ring to which the amino groups at both ends are bonded may be substituted with a monovalent group.)

In addition, in the present invention, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Boc represents a tert-butoxycarbonyl group.

According to the present invention, it is a liquid crystal aligning agent that expands the range of light irradiation amount from which a liquid crystal aligning film with small deviation (non-uniformity) of the twist angle of the liquid crystal within the plane of the liquid crystal aligning film is obtained, and also does not cause display unevenness resulting from the cleaning process. A liquid crystal aligning agent that forms a liquid crystal aligning film with a high water contact angle for obtaining a liquid crystal aligning film, a liquid crystal aligning film obtained from the liquid crystal aligning agent, and a high-performance liquid crystal display element provided with the liquid crystal aligning film are obtained.

The mechanism by which the above effects of the present invention are obtained is not necessarily clear, but is roughly estimated as follows. The oxyaniline structure contained in the diamine (0) of the present invention allows a liquid crystal alignment film with a small variation in the twist angle of the liquid crystal to be obtained, and the water contact angle is increased by introducing a hydrophobic hydrocarbon such as an aromatic ring or alkylene. It seems that the effect has been achieved.

<Specific diamine>

The liquid crystal aligning agent of this invention is a polyimide precursor obtained using the diamine component containing diamine (0) (in this invention, it is also called specific diamine) represented by the following formula ( _DA ) as mentioned above, and its polyimide. It is characterized by containing at least one type of polymer (P) selected from the group consisting of polyimide, which is an imidate of the precursor.

[Formula 2]

In the above formula ( _DA ), Ar, m, and n are each as defined above.

In the above formula ( _DA ), m and n are preferably 1 to 2 from the viewpoint of obtaining high liquid crystal orientation.

The monovalent group substituting the hydrogen atom on the benzene ring, biphenyl structure, or naphthalene ring of Ar in the above formula ( _DA ) includes a halogen atom, an alkyl group with 1 to 3 carbon atoms, an alkenyl group with 2 to 3 carbon atoms, Alkoxy group with 1 to 3 carbon atoms, fluoroalkyl group with 1 to 3 carbon atoms, fluoroalkenyl group with 2 to 3 carbon atoms, fluoroalkoxy group with 1 to 3 carbon atoms, carboxyl group, hydroxy group, alkyloxy with 1 to 3 carbon atoms Carbonyl group, cyano group, nitro group, etc. can be mentioned. Among them, a halogen atom, an alkyl group with 1 to 3 carbon atoms, an alkoxy group with 1 to 3 carbon atoms, a fluoroalkyl group with 1 to 3 carbon atoms, or a fluoroalkoxy group with 1 to 3 carbon atoms is preferable.

Additionally, any hydrogen atom on the benzene ring to which the amino groups at both ends are bonded may be substituted with a monovalent group, and specific examples of the monovalent group include the monovalent groups exemplified by Ar in the formula ( _DA ) above. and the same thing can be mentioned as a preferable aspect.

Preferred examples of the divalent aromatic group represented by Ar include 1,4-phenylene, 1,3-phenylene, 2-methyl-1,4-phenylene, 2-ethyl-1,4-phenylene, 2- Propyl-1,4-phenylene, 2-isopropyl-1,4-phenylene, 2-methoxy-1,4-phenylene, 2-ethoxy-1,4-phenylene, 2-propoxy- 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-dimethyl-1,4-phenylene, 4-methyl-1,3-phenylene, 5-methyl-1,3 -Phenylene, 4-fluoro-1,3-phenylene, 2,3,5,6-tetramethyl-1,4-phenylene, biphenyl-4,4'-diyl, 2-methylbiphenyl- 4,4'-diyl, 2-ethylbiphenyl-4,4'-diyl, 2-propylbiphenyl-4,4'-diyl, 2-methoxybiphenyl-4,4'-diyl, 2-ethoxybi Phenyl-4,4'-diyl, 2-fluorobiphenyl-4,4'-diyl, 3-methylbiphenyl-4,4'-diyl, 3-ethylbiphenyl-4,4'-diyl, 3- Propylbiphenyl-4,4'-diyl, 3-methoxybiphenyl-4,4'-diyl, 3-ethoxybiphenyl-4,4'-diyl, 3-fluorobiphenyl-4,4'-diyl, 2,2'-dimethylbiphenyl-4,4'-diyl, 3,3'-dimethylbiphenyl-4,4'-diyl, biphenyl-3,3'-diyl, 5-methylbiphenyl-3, 3'-diyl, 5,5'-dimethylbiphenyl-3,3'-diyl, 1,5-naphthylene, 2,6-naphthylene, or 1-methyl-2,6-naphthylene, etc. there is.

Preferred examples of the above formula ( _DA ) include the following formulas (d _A -1) to (d _A -3). In the following formulas (d _A -1) to (d _A -3), any hydrogen atom on the benzene ring to which the amino group at both ends is bonded, the benzene ring to which the alkylene group is bonded, the biphenyl structure, or the naphthalene ring is 1 It may be substituted with a valent group, and specific examples of the monovalent group include the monovalent groups exemplified by Ar in the above formula ( _DA ), and the same can be cited as preferred embodiments. A more preferable monovalent group as a substituent for the hydrogen atom on the benzene ring to which the amino groups at both ends in the above formulas (d _A -1) to (d _A -3) are bonded is a methyl group. Moreover, when the hydrogen atoms on the benzene ring to which the amino groups at both ends are bonded are substituted, it is more preferable that 1 to 2 hydrogen atoms are substituted in each benzene ring, and it is still more preferable that one hydrogen atom is substituted. . At least one hydrogen atom on the benzene ring to which the amino groups at both ends are bonded is a halogen atom, an alkyl group with 1 to 3 carbon atoms, an alkoxy group with 1 to 3 carbon atoms, a fluoroalkyl group with 1 to 3 carbon atoms, or a fluorine group with 1 to 3 carbon atoms. It may be substituted with a loalkoxy group.

[Formula 3]

(m and n each independently have the above definitions.)

(Polymer (P))

The polymer (P) contained in the liquid crystal aligning agent of this invention is a polyimide precursor obtained using the diamine component containing the said diamine (0), or the imidide of this polyimide precursor. Here, the polyimide precursor is a polymer from which polyimide can be obtained by imidizing polyamic acid, polyamic acid ester, etc. Polymer (P) may be used individually by 1 type, or may be used in combination of 2 or more types.

The polymer (P) may be a polymer having at least one type of repeating unit selected from the group consisting of a repeating unit (p1) represented by the following formula (1) and an imidized structural unit of the repeating unit (p1).

[Formula 4]

_{( In} formula (1), )

The monovalent organic group for R and Z in the above formula (1) is a monovalent hydrocarbon group having 1 to 6 carbon atoms, and the methylene group of the hydrocarbon group is -O-, -S-, -CO-, - 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 6 carbon atoms), - At least one of the monovalent group A substituted with SO ₂ - or the like, the monovalent hydrocarbon group, or the hydrogen atom bonded to the carbon atom of the monovalent group A is a halogen atom, a hydroxy group, an alkoxy group, a nitro group, A monovalent group or heterocycle formed by substitution with an amino group, mercapto group, nitroso group, alkylsilyl group, alkoxysilyl group, silanol group, sulfino group, phosphino group, carboxyl group, cyano group, sulfo group, acyl group, etc. A monovalent group may be mentioned.

The monovalent organic group for R and Z in the above formula (1) includes, among others, 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 tert-group. A toxycarbonyl 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 appropriately 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.

Examples of X ₁ in the formula (1) include a tetravalent organic group derived from tetracarboxylic dianhydride or a derivative thereof described later. Preferred embodiments of tetracarboxylic dianhydride or its derivatives in X ₁ include preferred embodiments of tetracarboxylic dianhydride or derivatives thereof that can be used in the synthesis of polymer (P) described later.

Polyamic acid (P'), which is the polyimide precursor of the polymer (P), can be obtained through a polymerization reaction of a diamine component containing the diamine (0) and a tetracarboxylic acid component. The said diamine (0) may be used individually by 1 type, or may be used in combination of 2 or more types.

The amount of diamine (0) used is preferably 5 mol% or more, more preferably 10 mol% or more, and still more preferably 20 mol% or more, relative to all diamine components.

The diamine component used for producing the polyamic acid (P') may contain diamines other than diamine (0) (hereinafter also referred to as other diamines). When using other diamines in addition to the diamine (0), the amount of diamine (0) used relative to the diamine component is preferably 90 mol% or less, and more preferably 80 mol% or less.

Examples of other diamines are given below, but they are not limited to these. The other diamines mentioned above may be used individually by 1 type, or may be used in combination of 2 or more types. p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, m-phenylenediamine, 2,4-dimethyl-m-phenyl Lendiamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diamino Biphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl, 2,2'-difluoro-4 ,4'-diaminobiphenyl, 3,3'-difluoro-4,4'-diaminobiphenyl, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl , 3,3'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 4,4'-diaminobiphenyl, 3,3'-dia Minobiphenyl, 2,2'-diaminobiphenyl, 2,3'-diaminobiphenyl, diamine represented by the following formulas (d _AL -1) to (d _AL -10), 1,7-bis (4 -Aminophenoxy)heptane, 1,7-bis(3-aminophenoxy)heptane, 1,8-bis(4-aminophenoxy)octane, 1,8-bis(3-aminophenoxy)octane, 1 ,9-bis(4-aminophenoxy)nonane, 1,9-bis(3-aminophenoxy)nonane, 1,10-bis(4-aminophenoxy)decane, 1,10-bis(3-amino) Phenoxy)decane, 1,11-bis(4-aminophenoxy)undecane, 1,11-bis(3-aminophenoxy)undecane, 1,12-bis(4-aminophenoxy)dodecane, 1,12-bis(3-aminophenoxy)dodecane, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 4,4'-bis( 4-aminophenoxy)biphenyl, 4,4'-bis(4-aminophenoxy)diphenyl ether, 1,4-bis[4-(4-aminophenoxy)phenoxy]benzene, 1,2- Bis(6-amino-2-naphthyloxy)ethane, 1,2-bis(6-amino-2-naphthyl)ethane, 6-[2-(4-aminophenoxy)ethoxy]-2-naph Tylamine, 1,4-phenylenebis(4-aminobenzoate), 1,4-phenylenebis(3-aminobenzoate), 1,3-phenylenebis(4-aminobenzoate), 1, 3-phenylenebis(3-aminobenzoate), bis(4-aminophenyl)terephthalate, bis(3-aminophenyl)terephthalate, bis(4-aminophenyl)isophthalate, bis(3-aminophenyl) Isophthalate (hereinafter, these diamines are also referred to as other diamines (a)); Diamine having a photo-alignment group such as 4,4'-diaminoazobenzene or diaminothran; diamines having a photopolymerizable group at the terminal, such as 2-(2,4-diaminophenoxy)ethyl methacrylate or 2,4-diamino-N,N-diallylaniline; 1-(4-(2-(2,4-diaminophenoxy)ethoxy)phenyl)-2-hydroxy-2-methylpropanone, 2-(4-(2-hydroxy-2-methylpropanone) Diamines having a radical polymerization initiator function, such as panoyl)phenoxy)ethyl 3,5-diaminobenzoate; Diamines having an amide bond such as 4,4'-diaminobenzanilide, 1,3-bis(4-aminophenyl)urea, 1,3-bis(4-aminobenzyl)urea, 1,3-bis(4) Diamines having a urea bond, such as -aminophenethyl)urea; 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 2,2-bis[4-(4-aminophenoxy)phenyl] Propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis(4-aminophenyl)hexafluoropropane, 2,2-bis(3-aminophenyl) ) Hexafluoropropane, 2,2-bis (3-amino-4-methylphenyl) hexafluoropropane, 2,2-bis (4-aminophenyl) propane, 2,2-bis (3-aminophenyl) propane , 2,2-bis(3-amino-4-methylphenyl)propane, 4,4'-diaminobenzophenone, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl) ) Benzene, 1,4-bis (4-aminobenzyl) benzene; 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, 1,4 -bis-(4-aminophenyl)-piperazine, 3,6-diaminoacridine, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, N- [3-(1H-imidazol-1-yl)propyl]3,5-diaminobenzamide, 4-[4-[(4-aminophenoxy)methyl]-4,5-dihydro-4-methyl -2-oxazolyl]-benzenamine, or heterocyclic ring-containing diamines such as diamines represented by the following formulas (z-1) to (z-13), or 4,4'-diaminodiphenylamine, 4, 4'-diaminodiphenyl-N-methylamine, N,N'-bis(4-aminophenyl)-benzidine, N,N'-bis(4-aminophenyl)-N,N'-dimethylbenzidine, or , N,N'-bis(4-aminophenyl)-N,N'-dimethyl-1,4-benzenediamine, a heterocyclic ring containing a nitrogen atom, represented by diamines having a diphenylamine structure, such as secondary amino group. and a diamine having at least one nitrogen atom-containing structure (hereinafter also referred to as a specific nitrogen atom-containing structure) selected from the group consisting of a tertiary amino group (however, an amino group bound to a protecting group that is desorbed by heating and replaced by a hydrogen atom) does not have in the molecule) ; 2,4-diaminophenol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, 4,4'-diaminophenol Mino-3,3'-dihydroxybiphenyl; 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 3,5-diaminobenzoic acid, 4,4'-diaminobiphenyl-3-carboxylic acid, 4,4'-diaminodiphenylmethane -3-carboxylic acid, 1,2-bis(4-aminophenyl)ethane-3-carboxylic acid, 4,4'-diaminobiphenyl-3,3'-dicarboxylic acid, 4,4'-Diaminobiphenyl-2,2'-dicarboxylic acid, 3,3'-diaminobiphenyl-4,4'-dicarboxylic acid, 3,3'-diaminobiphenyl-2,4' -Dicarboxylic acid, 4,4'-diaminodiphenylmethane-3,3'-dicarboxylic acid, 1,2-bis(4-aminophenyl)ethane-3,3'-dicarboxylic acid, Diamines having a carboxyl group such as 4,4'-diaminodiphenyl ether-3,3'-dicarboxylic acid; 4-(2-(methylamino)ethyl)aniline, 4-(2-aminoethyl)aniline, 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; Groups of the following formulas (5-1) to (5-6), such as "-N(D)-" (D represents a protecting group that is removed by heating and replaced by a hydrogen atom, and is preferably a carbamate-based protecting group, More preferably, it is a tert-butoxycarbonyl group.) Diamine having, cholestanyloxy-3,5-diaminobenzene, cholestanyloxy-3,5-diaminobenzene, cholestanyloxy-2,4 -Diaminobenzene, 3,5-diaminobenzoic acid cholestanyl, 3,5-diaminobenzoic acid cholestanyl, 3,5-diaminobenzoic acid lanostanyl and 3,6-bis (4-aminobenzoyloxy) Diamines having steroid skeletons such as cholestane, diamines represented by the following formulas (V-1) to (V-2); Diamines having a siloxane bond such as 1,3-bis(3-aminopropyl)-tetramethyldisiloxane; Metaxylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, 1,3-bis(aminomethyl)cyclohexane, 1,4-diaminocyclohexane, 4,4'- Methylenebis(cyclohexylamine), a diamine in which two amino groups are bonded to a group represented by any of the formulas (Y-1) to (Y-167) described in International Publication No. 2018/117239, etc.

[Formula 5]

(In formulas (d _AL -6) and (d _AL -8), m1 and m2 each independently have the above definitions.)

[Formula 6]

[Formula 7]

[Formula 8]

[Formula 9]

In the above formula (V-1), m and n are each independently integers from 0 to 3, and satisfy 1 ≤ m + n ≤ 4. j is an integer of 0 or 1. X ¹ is -(CH ₂ ) _a -(A is 1 to 15 integers), -Conh-, -NHCO-, -co -N (CH ₃ ) -, -NH-, -o-, -CH ₂ O-, -CH ₂ -OCO-, -COO-, or -OCO-. R ¹ is a fluorine atom, a fluorine atom-containing alkyl group with 1 to 10 carbon atoms, a fluorine atom-containing alkoxy group with 1 to 10 carbon atoms, an alkyl group with 1 to 10 carbon atoms, an alkoxy group with 1 to 10 carbon atoms, and an alkoxy group with 2 to 10 carbon atoms. It represents a monovalent group such as an alkyl group. In the above formula (V-2), X ² represents -O-, -CH ₂ O-, -CH ₂ -OCO-, -COO-, or -OCO-. When there are two m, n, X ¹ , and R ¹ , each independently has the above definition.

The diamine component used in the production of the polyamic acid (P') contains at least one diamine selected from the group consisting of the other diamines (a) above, from the viewpoint of appropriately obtaining the effects of the present invention. It is desirable to do so.

When using other diamines in addition to the diamine (0), the amount of the other diamines is preferably 10 to 90 mol%, based on the total diamine components used in the production of polymer (P). Preferably it is 20 to 80 mol%.

(tetracarboxylic acid component)

When producing the polyamic acid (P'), the tetracarboxylic acid component to be reacted with the diamine component is not only tetracarboxylic dianhydride, but also tetracarboxylic acid, tetracarboxylic acid dihalide, and tetracarboxylic acid dialkyl ester. , or a tetracarboxylic acid dianhydride derivative such as tetracarboxylic acid dialkyl ester dihalide can also be used.

Examples of the tetracarboxylic dianhydride or its derivatives include acyclic aliphatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, aromatic tetracarboxylic dianhydride, and derivatives thereof. Among them, it is more preferable to include tetracarboxylic dianhydride or a derivative thereof having at least one partial structure selected from the group consisting of a benzene ring, a cyclobutane ring, a cyclopentane ring, and a cyclohexane ring. In particular, it is more preferable to include tetracarboxylic dianhydride or a derivative thereof having at least one structure selected from the group consisting of a cyclobutane ring, a cyclopentane ring, and a cyclohexane ring.

The said tetracarboxylic dianhydride or its derivative(s) may be used individually by 1 type, or may be used in combination of 2 or more types.

Additionally, acyclic aliphatic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxyl groups bonded to a chain hydrocarbon structure. However, it does not have to consist of only a chain hydrocarbon structure, and may have an alicyclic structure or an aromatic ring structure in part.

Alicyclic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxyl groups, including at least one carboxyl group bonded to the alicyclic structure. However, none of these four carboxyl groups are bonded to the aromatic ring. In addition, it does not need to be composed of only an alicyclic structure, and may have a chain hydrocarbon structure or an aromatic ring structure in part.

Aromatic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxyl groups, including at least one carboxyl group bonded to an aromatic ring. However, it does not need to be composed of only an aromatic ring structure, and may have a chain-type hydrocarbon structure or an alicyclic structure as part of it.

The tetracarboxylic acid component that can be used in the production of the polyamic acid (P') is preferably the following tetracarboxylic dianhydride or its derivatives (in the present invention, these are collectively referred to as specific tetracarboxylic acid derivatives) Also called) includes.

Acyclic aliphatic tetracarboxylic dianhydride such as 1,2,3,4-butane tetracarboxylic dianhydride; 1,2,3,4-Cyclobutanetetracarboxylic acid dianhydride, 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,3-dimethyl-1,2, 3,4-Cyclobutanetetracarboxylic dianhydride, 1,3-dichloro-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2 ,3,4-Cyclobutanetetracarboxylic acid dianhydride, 1,3-difluoro-1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,3-bis(trifluoromethyl) -1,2,3,4-Cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride Water, 3,3',4,4'-dicyclohexyltetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 4-(2,5-dioxotetrahydrofuran-3 -yl) tetrahydronaphthalene-1,2-dicarboxylic acid anhydride, 5-(2,5-dioxotetrahydrofuran-3-yl)-3a,4,5,9b-tetrahydronaphtho [1, 2-c]furan-1,3-dione, 5-(2,5-dioxotetrahydrofuran-3-yl)-8-methyl-3a,4,5,9b-tetrahydronaphtho[1,2 -c]furan-1,3-dione, bicyclo[2.2.2]octa-7-en-2,3,5,6-tetracarboxylic dianhydride, bicyclo[2.2.2]octane-2, Alicyclic tetracarboxylic acids such as 3,5,6-tetracarboxylic dianhydride, 2,4,6,8-tetracarboxybicyclo[3.3.0]octane-2:4,6:8-dianhydride, etc. dianhydride; Pyromellitic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-diphenylsulfone tetracarboxylic dianhydride, 1,4,5 ,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride, 3,3 ',4,4'-Biphenyltetracarboxylic dianhydride, 2,2',3,3'-Biphenyltetracarboxylic dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy )-2,2-Diphenylpropane dianhydride, ethylene glycol bisanhydrotrimellitate, 4,4'-(hexafluoroisopropylidene)diphthalic anhydride, 4,4'-carbonyldiphthalic anhydride, 4 Aromatic tetracarboxylic dianhydride such as 4'-(1,4-phenylenedioxy)bis(phthalic anhydride) or 4,4'-methylenedi(1,4-phenylenedimethylene)bis(phthalic anhydride) ; In addition, tetracarboxylic dianhydride described in Japanese Patent Publication No. 2010-97188, etc.

Preferred examples of the specific tetracarboxylic acid derivatives include 1,2,3,4-butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, and 1,2-dimethyl. -1,2,3,4-Cyclobutane tetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2,3,4-tetra Methyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-difluoro-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-bis( Trifluoromethyl)-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexane Tetracarboxylic dianhydride, 3,3',4,4'-dicyclohexyltetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 5-(2,5-dioxo Tetrahydrofuran-3-yl)-3a,4,5,9b-tetrahydronaphtho[1,2-c]furan-1,3-dione, 5-(2,5-dioxotetrahydrofuran-3 -yl)-8-methyl-3a,4,5,9b-tetrahydronaphtho[1,2-c]furan-1,3-dione, 2,4,6,8-tetracarboxybicyclo[3.3. 0]octane-2:4,6:8-dianhydride, pyromellitic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'- Diphenylsulfone tetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3',4,4 '-Diphenyl ether tetracarboxylic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic dianhydride, or their derivatives.

The usage ratio of the specific tetracarboxylic acid derivative is preferably 10 mol% or more, more preferably 20 mol% or more, and still more preferably 50 mol% or more, relative to the total tetracarboxylic acid components used.

(Liquid crystal aligning agent)

The liquid crystal aligning agent of this invention is a liquid composition in which the polymer (P) and other components used as needed are preferably dispersed or dissolved in an appropriate solvent.

The total content of the polymer components contained in the liquid crystal aligning agent of the present invention can be appropriately changed also by setting the thickness of the coating film to be formed, but in terms of forming a uniform and defect-free coating film, it is added to the total mass of the liquid crystal aligning agent. It is preferably 1% by mass or more, and from the viewpoint of storage stability of the solution, 10% by mass or less is preferable.

The content of the polymer (P) used in the present invention is preferably 1 to 100 parts by mass, more preferably 10 to 100 parts by mass, and more preferably 20 to 100 parts by mass, relative to a total of 100 parts by mass of the polymer contained in the liquid crystal aligning agent. Particularly desirable.

The liquid crystal aligning agent of this invention may contain other polymers other than polymer (P). Specific examples of other polymers include at least one polymer selected from the group consisting of a polyimide precursor obtained by using a diamine component without the above-mentioned specific diamine and a polyimide that is an imidate of the polyimide precursor (the present invention (also called polymer (B)), polysiloxane, polyester, polyamide, polyurea, polyorganosiloxane, cellulose derivative, polyacetal, polystyrene derivative, poly(styrene-maleic anhydride) copolymer, poly(isobutylene) -maleic anhydride) copolymer, poly(vinyl ether-maleic anhydride) copolymer, poly(styrene-phenylmaleimide) derivative, and poly(meth)acrylate.

Specific examples of poly(styrene-maleic anhydride) copolymer include SMA1000, SMA2000, SMA3000 (manufactured by Cray Valley), GSM301 (manufactured by Gigi Shellac Manufacturing Company), etc., and poly(isobutylene-maleic acid) Specific examples of the anhydride copolymer include Isobam-600 (manufactured by Kuraray Co., Ltd.). Specific examples of the poly(vinyl ether-maleic anhydride) copolymer include Gantrez AN-139 (methyl vinyl ether maleic anhydride resin, manufactured by Ashland Corporation).

Among them, polymer (B) is more preferable because it reduces the afterimage resulting from residual DC.

The other polymers mentioned above may be used individually, or may be used in combination of two 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.

Content of the said polymer (P) may be 90 mass parts or less, and may be 80 mass parts or less with respect to a total of 100 mass parts of polymers contained in a liquid crystal aligning agent.

(Polymer (B))

Specific examples of the tetracarboxylic acid component used in producing the polymer (B) include the same compounds as those exemplified for polymer (P), including preferred examples. The tetracarboxylic acid component used in the production of polymer (B) is more preferably tetracarboxylic acid having at least one partial structure selected from the group consisting of a benzene ring, a cyclobutane ring, a cyclopentane ring, and a cyclohexane ring. It is more preferable to include carboxylic acid dianhydride or a derivative thereof, more preferably the specific tetracarboxylic acid derivative, and most preferable to use a more preferable example of the specific tetracarboxylic acid derivative.

In addition, the amount of the specific tetracarboxylic acid derivative used is preferably 10 mol% or more, more preferably 20 mol% or more, and 50 mol%, relative to the total tetracarboxylic acid components used in the production of polymer (B). % or more is more preferable.

As a diamine component for obtaining polymer (B), the diamine exemplified in the said polymer (P) can be mentioned, for example. Among them, diamine, 3,3'-diaminodiphenyl ether, and 3,4'-diaminodiphenyl ether having at least one group selected from the group consisting of a urea bond, an amide bond, a carboxyl group, and a hydroxy group in the molecule. , 4,4'-diaminodiphenyl ether, diamines represented by the above formulas (d _AL -1) to (d _AL -10), and at least one member selected from the group consisting of diamines having the above specific nitrogen atom-containing structure. It is preferable to include diamine (in the present invention, these are also referred to as specific diamine (b)). The said diamine component may be used individually by 1 type of diamine, and may be used in combination of 2 or more types.

When using the above specific diamine (b), the usage amount is preferably 10 mol% or more, and more preferably 20 mol% or more of the total diamine components used in producing the polymer (B). When using diamines other than the specific diamine (b), the usage amount is preferably 90 mol% or less, and more preferably 80 mol% or less of the total diamine components used for production of the polymer (B).

(Manufacture of polyamic acid)

Manufacture of polyamic acid is carried out by reacting a diamine component and a tetracarboxylic acid component in an organic solvent. The ratio of the tetracarboxylic acid component and the diamine component used in the production reaction of the polyamic acid is preferably such that the acid anhydride group of the tetracarboxylic acid component is 0.5 to 2 equivalents per 1 equivalent of the amino group of the diamine component, More preferably, it is 0.8 to 1.2 equivalents. As in a normal polycondensation reaction, the closer the equivalent weight of the acid anhydride group of the tetracarboxylic acid component is to 1 equivalent, the larger the molecular weight of the polyamic acid produced.

The reaction temperature in the production of polyamic acid is preferably -20 to 150°C, and more preferably 0 to 100°C. Moreover, the reaction time is preferably 0.1 to 24 hours, and more preferably 0.5 to 12 hours. Production of polyamic acid can be carried out at any concentration. The concentration of polyamic acid is preferably 1 to 50 mass%, more preferably 5 to 30 mass%. The reaction may be carried out at a high concentration in the initial stage, and then a solvent may be added.

Specific examples of the organic solvent include cyclohexanone, cyclopentanone, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, and N,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, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene Solvents such as glycol monoethyl ether, ethylene glycol monopropyl ether, diethylene glycol monomethyl ether, or diethylene glycol monoethyl ether can be used.

(Manufacture of polyamic acid ester)

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.

(Manufacture of polyimide)

Polyimide can be obtained by ring-closing (imidizing) polyimide precursors such as the polyamic acid or polyamic acid ester. In addition, the imidation rate as used herein refers to the ratio of the imide group to the total amount of the imide group derived from tetracarboxylic dianhydride or its derivative and the carboxyl group (or its derivative). The imidization rate does not necessarily have to be 100% and can be arbitrarily adjusted depending on the use or purpose.

Methods for imidizing a polyimide precursor include thermal imidization in which a solution of the polyimide precursor is heated as is, or catalytic imidization in which a catalyst is added to the solution of the polyimide precursor.

The temperature in the case of thermally imidating a polyimide precursor in a solution is 100-400 degreeC, More preferably, it is 120-250 degreeC, and it is preferable to carry out while removing the water produced|generated by an imidation reaction to the outside of the system.

Catalyst imidization of the polyimide precursor can be performed by adding a basic catalyst and an acid anhydride to the solution of the polyimide precursor, and preferably stirring at -20 to 250°C, more preferably 0 to 180°C. The amount of the basic catalyst is preferably 0.5 to 30 mole times the amic acid group, more preferably 2 to 20 mole times, and the amount of the acid anhydride is preferably 1 to 50 mole times the amic acid group, more preferably 3 to 30 mole times the amic acid group. Basic catalysts include pyridine, triethylamine, trimethylamine, tributylamine, or trioctylamine, and among them, pyridine is preferable because it has an appropriate basicity to proceed with the reaction. Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, and pyromellitic anhydride. Among these, acetic anhydride is preferred because it facilitates purification after completion of the reaction. The imidization rate by catalyst imidization can be controlled by adjusting the catalyst amount, reaction temperature, and reaction time.

When recovering the produced polyimide precursor or polyimide from the polyimide precursor or polyimide reaction solution, the reaction solution may be added to a solvent to cause precipitation. Solvents used for precipitation include methanol, ethanol, isopropyl alcohol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, toluene, benzene, and water. The polymer precipitated by adding it to the solvent can be recovered by filtration and then dried under normal or reduced pressure, at room temperature, or by heating. Additionally, if the recovered polymer is redissolved in an organic solvent and the reprecipitation and recovery operation is repeated 2 to 10 times, impurities in the polymer can be reduced. Examples of solvents at this time include alcohols, ketones, and hydrocarbons. It is preferable to use three or more types of solvents selected from among these, as the purification efficiency further increases.

When producing the polyimide precursor or polyimide in the present invention, a tetracarboxylic acid component containing tetracarboxylic dianhydride or a derivative thereof, and a diamine component containing the above diamine, together with a suitable end capping agent. You may use to produce 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 terminal of the polyimide precursor or polyimide in the present invention include an amino group, a carboxyl group, an acid anhydride group, or a group derived from an end capping agent described later. The amino group, carboxyl group, and acid anhydride group can be obtained by a conventional condensation reaction, or by capping the ends using the following end capping agent.

Examples of end capping agents include acetic anhydride, maleic anhydride, nadic anhydride, phthalic anhydride, itaconic anhydride, 1,2-cyclohexanedicarboxylic anhydride, 3-hydroxyphthalic anhydride, and trimellitic anhydride. , 3-(3-trimethoxysilyl)propyl)-3,4-dihydrofuran-2,5-dione, 4,5,6,7-tetrafluoroisobenzofuran-1,3-dione, 4 - Acid anhydrides such as ethynyl phthalic anhydride; Diester bicarbonate compounds such as di-tert-butyl bicarbonate and diallyl bicarbonate; 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; Isocyanates having an unsaturated bond such as ethyl isocyanate, phenyl isocyanate, naphthyl isocyanate, or 2-acryloyloxyethyl isocyanate and 2-methacryloyloxyethyl isocyanate can be 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.

The weight average molecular weight (Mw) of the polyimide precursor 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 of the liquid crystal display element can be ensured.

The organic solvent contained in the liquid crystal aligning agent which concerns on this invention will not be specifically limited as long as the polymer (P) and other polymers added as needed are dissolved uniformly. For example, N,N-dimethylformamide, N,N-dimethylacetamide, N,N-dimethyllactonamide, N,N-dimethylpropionamide, tetramethylurea, 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-pyrrolidone, N-isopropyl-2-pyrrolidone, N-(n-butyl)-2-pyrrolidone, N-(tert-butyl)-2-pyrrolidone, N-(n-pentyl)-2-p Rolidone, N-(3-methoxypropyl)-2-pyrrolidone, N-(2-ethoxyethyl)-2-pyrrolidone, N-(4-methoxybutyl)-2-pyrrolidone , N-cyclohexyl-2-pyrrolidone (these are collectively referred to as good solvents), etc. 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, 20-90 mass % is more preferable, and 30-80 mass % is especially preferable.

Moreover, the organic solvent contained in a liquid crystal aligning agent is the use of the mixed solvent which used together the said solvent and the solvent (also called a poor solvent) which improves the coating property at the time of apply|coating a liquid crystal aligning agent and the surface smoothness of a coating film. desirable. Specific examples of poor solvents are given below, but are not limited to these. 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.

Poor solvents include, for example, diisopropyl ether, diisobutyl ether, diisobutylcarbinol (2,6-dimethyl-4-heptanol), ethylene glycol dimethyl ether, ethylene glycol diethyl ether, and ethylene glycol. Dibutyl ether, 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 mono Methyl ether acetate, 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, diethylene glycol mono Butyl ether acetate, 2-(2-ethoxyethoxy)ethyl acetate, diethylene glycol diacetate, propylene glycol diacetate, n-butyl acetate, propylene glycol monoethyl ether acetate, cyclohexyl acetate, 4-methyl-2 acetate. -Pentyl, 3-methoxymethyl propionate, ethyl 3-ethoxypropionate, 3-methoxypropyl propionate, 3-methoxybutyl propionate, n-butyl lactate, isoamyl lactate, diethylene glycol monoethyl ether, diiso Butyl ketone (2,6-dimethyl-4-heptanone), etc. can be mentioned.

Among them, diisobutylcarbinol, propylene glycol monobutyl ether, propylene glycol diacetate, diethylene glycol diethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, 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-dimethyllactonamide 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-dimethyllactoamide and ethylene glycol monobutyl ether, N,N-dimethyllactoamide and propylene glycol diacetate, N-ethyl-2-pyrrolidone and 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, and 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 monomethyl 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 monomethyl 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. Lactamide and diisobutyl ketone, N-methyl-2-pyrrolidone, ethylene glycol monobutyl ether, 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, 4-hydroxy-4-methyl-2-pentanone, cyclohexanone and propylene glycol monomethyl ether, cyclopentanone and propylene glycol monomethyl ether, N-methyl-2-p. Examples include rolidone, cyclohexanone, and propylene glycol monomethyl ether.

(Liquid crystal aligning agent)

In addition to the polymer (P), the other polymers, and the organic solvent, the liquid crystal aligning agent of the present invention may contain other components (hereinafter also referred to as additive components). Such additive components include, for example, a crosslinkable compound having at least one substituent selected from oxiranyl group, oxetanyl group, blocked isocyanate group, oxazoline group, cyclocarbonate group, hydroxy group and alkoxy group, And at least one crosslinkable compound selected from the group consisting of crosslinkable compounds having a polymerizable unsaturated group, a functional silane compound, a metal chelate compound, a curing accelerator, a surfactant, an antioxidant, a sensitizer, a preservative, and the resulting liquid crystal alignment film. Examples include compounds for adjusting dielectric constant or electrical resistance.

Preferred specific examples of the crosslinkable compound include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, and polypropylene glycol diglycidyl. Diyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, dibromoneopentyl glycol diglycidyl ether, 1,3,5,6 -Tetraglycidyl-2,4-hexanediol, bisphenol A-type epoxy resins such as Epicoat 828 (manufactured by Mitsubishi Chemical Corporation), bisphenol F-type epoxy resins such as Epicoat 807 (manufactured by Mitsubishi Chemical Corporation), YX-8000 Hydrogenated bisphenol A-type epoxy resins such as (manufactured by Mitsubishi Chemical Corporation), biphenyl skeleton-containing epoxy resins such as YX6954BH30 (manufactured by Mitsubishi Chemical Corporation), phenol novolak-type epoxy resins such as EPPN-201 (manufactured by Nippon Chemical Company), (o,m,p-)cresol novolak-type epoxy resins such as EOCN-102S (manufactured by Nippon Chemical Co., Ltd.), triglycidyl isocyanurate such as TEPIC (manufactured by Nissan Chemical Co., Ltd.), and Celoxide 2021P (Daicel Chemical Industries, Ltd.) alicyclic epoxy resins such as (manufactured by), N,N,N',N'-tetraglycidyl-m-xylylenediamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, Or compounds containing a tertiary nitrogen atom such as N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, tetrakis(glycidyloxymethyl)methane, etc. Compounds having two or more oxiranyl groups; Compounds having two or more oxetanyl groups described in paragraphs [0170] to [0175] of WO2011/132751; Colonate AP Stable M, Colonate 2503, 2515, 2507, 2513, 2555, Millionate MS-50 (above, manufactured by Tosoh Corporation), Takenate B-830, B-815N, B-820NSU, B-842N Compounds having a block isocyanate group such as B-846N, B-870N, B-874N, and B-882N (manufactured by Mitsui Chemicals Co., Ltd.); 2,2'-bis(2-oxazoline), 2,2'-bis(4-methyl-2-oxazoline), 2,2'-bis(5-methyl-2-oxazoline), 1,2 Compounds having an oxazoline group such as 4-tris-(2-oxazolinyl-2)-benzene and Epochros (manufactured by Nippon Catalyst Co., Ltd.); Compounds having a cyclocarbonate group described in paragraphs [0025] to [0030] and [0032] of publication WO2011/155577; N,N,N',N'-tetrakis(2-hydroxyethyl)adipoamide, 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl)propane, 2,2-bis (4-hydroxy-3,5-dimethoxymethylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl)-1,1,1,3,3,3-hexa Compounds having a hydroxy group or an alkoxy group such as fluoropropane; Glycerol mono(meth)acrylate, glycerol di(meth)acrylate (1,2-,1,3-form mixture), glycerol tris(meth)acrylate, glycerol 1,3-diglycerolate di(meth)acrylate Latex, pentaerythritol tri(meth)acrylate, diethylene glycol mono(meth)acrylate, triethylene glycol mono(meth)acrylate, tetraethylene glycol mono(meth)acrylate, pentaethylene glycol mono(meth)acrylate Compounds represented by hexaethylene glycol mono(meth)acrylate and hexaethylene glycol mono(meth)acrylate can be mentioned.

It is preferable that content of the said crosslinkable compound is 0.1-30 mass parts with respect to 100 mass parts of polymer components contained in a liquid crystal aligning agent, More preferably, it is 0.1-20 mass parts.

Compounds for adjusting the dielectric constant or electrical resistance include monoamines having a nitrogen atom-containing aromatic heterocycle, such as 3-picolylamine. It is preferable that content of the monoamine which has a nitrogen atom containing aromatic heterocycle is 0.1-30 mass parts with respect to 100 mass parts of polymer components contained in a liquid crystal aligning agent, More preferably, it is 0.1-20 mass parts.

Preferred specific examples of the functional silane compound include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltrimethoxysilane, Aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrime Toxysilane, 3-ureidopropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethyl Toxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxy Propylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, Tris [3-(trimethoxysilyl)propyl]isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-isocyanate propyltriethoxysilane, etc. It is preferable that content of a functional silane compound is 0.1-30 mass parts with respect to 100 mass parts of polymer components contained in a liquid crystal aligning agent, More preferably, it is 0.1-20 mass parts.

The solid content concentration in the liquid crystal aligning agent (the ratio of the total mass of components other than the solvent of the liquid crystal aligning agent to the total mass of the liquid crystal aligning agent) is appropriately selected in consideration of viscosity, volatility, etc., but is preferably 1 to 10. It is 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. For example, when using the spin coating method, it is particularly preferable that the solid content concentration is 1.5 to 4.5 mass%. In the case of using the printing method, it is particularly preferable to set the solid content concentration to 3 to 9% by mass, thereby setting the solution viscosity to 12 to 50 mPa·s. In the case of using the inkjet method, it is particularly preferable to set the solid content concentration to 1 to 5% by mass, thereby setting the solution viscosity to 3 to 15 mPa·s. The temperature when preparing the liquid crystal aligning agent is preferably 10 to 50°C, more preferably 20 to 30°C.

(Liquid crystal alignment film and liquid crystal display device)

The liquid crystal display element concerning this invention is equipped with the liquid crystal aligning film formed using the said liquid crystal aligning agent. The operation mode of the liquid crystal display element is not particularly limited, and includes, for example, TN method, STN method, vertical alignment method (including VA-MVA method, VA-PVA method, etc.), in-plane switching method (IPS method, FFS method) ), optical compensation bend method (OCB method), etc. can be applied to various operation modes.

The liquid crystal display device of the present invention is, for example, a method comprising the following steps (1) to (4), a method including steps (1) to (2) and (4), and steps (1) to ( 3), (4-2), and (4-4), or a method including steps (1) to (3), (4-3), and (4-4). .

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

Process (1) is a process of apply|coating a liquid crystal aligning agent on a board|substrate. Specific examples of step (1) are as follows.

A liquid crystal aligning agent 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, an inkjet method, or a spray method. Here, the material of the substrate is not particularly limited as long as it is a highly transparent substrate. In addition to glass and silicon nitride, plastics such as acrylic and polycarbonate 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 an IPS type or FFS type liquid crystal display device, a substrate on which an electrode made of a transparent conductive film or metal film patterned in a comb shape is formed and an opposing substrate on which no electrode is formed are used.

An IPS substrate, which is a comb electrode substrate used in an IPS type liquid crystal display device, includes, for example, a substrate, a plurality of linear electrodes formed on the substrate and arranged in a comb shape, and the linear electrodes are covered on the substrate. It has a liquid crystal alignment film formed.

In addition, the FFS substrate, which is a comb electrode substrate used in an FFS type liquid crystal display device, includes, for example, a base material, a surface electrode formed on the base material, an insulating film formed on the surface electrode, and a comb electrode formed on the insulating film. It has a plurality of linear electrodes arranged in a shape, and a liquid crystal alignment film formed on an insulating film so as to cover the linear electrodes.

More preferable examples of methods for applying a liquid crystal aligning agent to a substrate and forming a film include printing methods such as screen printing, offset printing, or flexo printing, spin coating methods, inkjet methods, or spray methods. Among them, coating and film forming methods by flexographic printing, spin coating, or inkjet methods 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. Specific examples of step (2) are as follows.

In step (1), 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 a solvent such as polyamic acid is evaporated. Thermal imidization of the polyimide precursor can be performed. The drying and baking steps after applying the liquid crystal aligning agent may be performed at any temperature and time, and may be performed multiple times. The temperature at which the liquid crystal aligning agent is baked can be carried out, for example, at 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 includes 1 to 10 minutes or 1 to 5 minutes. When performing thermal imidization of the polyimide precursor represented by polyamic acid, you may add the process of baking at, for example, 150-300 degreeC or 150-250 degreeC after the said process. The firing time is not particularly limited, but is, for example, 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, as the case may be. That is, in a liquid crystal display element of a horizontal alignment system such as an IPS system or an FFS system, an orientation ability imparting treatment is performed on the coating film. On the other hand, in a liquid crystal display element of a vertical alignment system such as a VA system or a PSA (Polymer Sustained Alignment) system, 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 alignment treatment method and a photo-alignment treatment method. Examples of the photo-alignment treatment method include irradiating radiation polarized in a certain direction to the surface of the film-like material and, in some cases, heat treatment to provide liquid crystal orientation (also referred to as liquid crystal orientation ability). As radiation, ultraviolet rays or visible rays with 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 , and more preferably 100 to 5,000 mJ/cm ² .

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.

Additionally, the coating film irradiated with polarized radiation by the above method or the coating film subjected to the rubbing orientation treatment may be subjected to contact treatment using water or a solvent. In addition, the film that has undergone the above-mentioned orientation treatment may be subjected to heat treatment without contact treatment. Additionally, heat treatment may be additionally performed on the film that has undergone the contact treatment.

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. The number of solvents may be one, or two or more types may be combined.

The temperature of the heat treatment for the coating film irradiated with the above radiation is more preferably 50 to 300°C, and still more preferably 120 to 250°C. The heat treatment time is preferably 1 to 30 minutes.

<Process (4): Process for manufacturing liquid crystal cells>

Two substrates on which the liquid crystal alignment film was formed as described above 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 injected and filled into the cell gap defined by the substrate surface and the sealant to bring it into contact with the film surface, and then the injection hole is sealed.

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 with a positive dielectric anisotropy is also referred to as a positive liquid crystal, and a liquid crystal composition with a negative dielectric anisotropy is also referred to as a negative liquid crystal.

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, a cycloalkane, It may contain a liquid crystal compound having a cycloalkene, a steroid skeleton, a benzene ring, or a naphthalene ring, or a compound having two or more rigid moieties (mesogenic skeletons) in the molecule that exhibit liquid crystallinity (for example, a rigid 2 It may contain a biphenyl structure, a bimesogenic compound in which a terphenyl structure is linked to an alkyl group, etc.). The liquid crystal composition may be a liquid crystal composition showing a nematic phase, a liquid crystal composition showing a smectic phase, or a liquid crystal composition showing a cholesteric phase.

Additionally, additives may be further added to the liquid crystal composition from the viewpoint of improving liquid crystal orientation. These additives include photopolymerizable monomers such as compounds having a polymerizable group ((meth)acryloyl group, etc.); Optically active compounds (e.g., S-811 manufactured by Merck & Co., Ltd., etc.); Antioxidants; UV absorber; pigment; Antifoaming agent; 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.

Negative liquid crystals include, for example, MLC-6608, MLC-6609, MLC-6610, MLC-6882, MLC-6886, MLC-7026, MLC-7026-000, MLC-7026-100 manufactured by Merck & Co., Ltd., or MLC-7029, etc. can be mentioned.

Moreover, in PSA mode, MLC-3023 manufactured by Merck & Co., Inc. can be cited as a liquid crystal containing a compound having a polymerizable group.

Additionally, the second method is a method called 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 addition, in any method, it is 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 orientation treatment is performed on the coating film, the two substrates are arranged to face each other so that the rubbing directions in each coating film are at a predetermined angle, for example, perpendicular or antiparallel.

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.

The liquid crystal aligning agent of this invention has a liquid crystal layer between a pair of board|substrates provided with electrodes, and contains a polymeric compound polymerized by at least one of an active energy ray and heat between a pair of board|substrates. It is also suitable for a liquid crystal display device (PSA type liquid crystal display device) manufactured through a process of arranging a liquid crystal composition and polymerizing a polymerizable compound by at least one of active energy ray irradiation and heating while applying a voltage between electrodes. It is used widely.

Furthermore, the liquid crystal aligning agent of the present invention has a liquid crystal layer between a pair of substrates provided with electrodes, and contains a polymerizable group polymerized by at least one of an active energy ray and heat between the pair of substrates. It is also preferably used for a liquid crystal display device (SC-PVA type liquid crystal display device) manufactured through a process of disposing a liquid crystal alignment film and applying a voltage between electrodes.

<Step (4-2): In case of PSA type liquid crystal display device>

The procedure is the same as (4) above except that the liquid crystal composition containing the polymerizable compound is injected or dropped. Examples of the polymerizable compound include polymerizable compounds having one or more polymerizable unsaturated groups such as an acrylate group or a methacrylate group in the molecule.

<Process (4-3): In case of SC-PVA liquid crystal display device>

After carrying out the same procedure as in (4) above, a method of manufacturing a liquid crystal display element through a process of irradiating ultraviolet rays, which will be described later, may be adopted. According to this method, as in the case of manufacturing the PSA type liquid crystal display device, a liquid crystal display device with excellent response speed can be obtained with a small amount of light irradiation. The compound having a polymerizable group may be a compound having one or more of the polymerizable unsaturated groups in the molecule, and its content is preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, based on 100 parts by mass of all polymer components. It is the mass part. Moreover, the polymer used for a liquid crystal aligning agent may have the said polymerizable group, For example, as such a polymer, the polymer obtained by using for reaction the diamine component containing the diamine which has the said photopolymerizable group at the terminal is mentioned. You can.

<Process (4-4): Process of irradiating ultraviolet rays>

The liquid crystal cell is irradiated with light while a voltage is applied between the conductive films of the pair of substrates obtained in (4-2) or (4-3) above. The voltage applied here can be, for example, direct current or alternating current of 5 to 50 V. In addition, as the light to be irradiated, for example, ultraviolet rays and visible rays containing light with a wavelength of 150 to 800 nm can be used, but ultraviolet rays containing light with a wavelength of 300 to 400 nm are preferable. As a light source of the irradiated light, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, an excimer laser, etc. can be used. The amount of light irradiated is preferably 1,000 to 200,000 J/m ² , and more preferably 1,000 to 100,000 J/m ² .

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 made of a polarizing film called "H film" in which iodine is absorbed while stretching polyvinyl alcohol and sandwiched between a cellulose acetate protective film, or a polarizing plate made of the H film itself. You can.

Example

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

(menstruum)

NMP: N-methyl-2-pyrrolidone

BCS: Ethylene glycol monobutyl ether

DMF: N,N-dimethylformamide

DMAc: N,N-dimethylacetamide

THF: tetrahydrofuran

IPA: 2-propanol

(Tetracarboxylic dianhydride)

CA-1: Compound represented by the following formula (CA-1)

[Formula 10]

(diamine)

DA-1 to DA-7: Compounds represented by the following formulas (DA-1) to (DA-7), respectively. Diamines included in the scope of the specific diamine of the present invention are compounds represented by the following formulas (DA-1), (DA-2), and (DA-7).

[Formula 11]

<Measurement of molecular weight>

It was measured using the room temperature GPC (gel permeation chromatography) device below, and Mn and Mw were calculated as values converted to polyethylene glycol and polyethylene oxide.

GPC device: GPC-101 (manufactured by Showa Denko), column: series of GPC KD-803 and GPC KD-805 (manufactured by Showa Denko), column temperature: 50°C, eluent: N,N-dimethylformamide (As additives, lithium bromide monohydrate (LiBr·H ₂ O) is 30 mmol/L, phosphoric acid/anhydrous crystal (o-phosphoric acid) is 30 mmol/L, and tetrahydrofuran (THF) is 10 mL/L), flow rate: 1.0 mL/min

Standard samples for preparing 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).

[Synthesis of monomers]

DA-1 was purchased and used as a commercial product (manufactured by Chemieliva Pharmaceutical).

DA-2 was synthesized using the synthesis method described in Journal of Molecular Structure (2018), 1169, 46-58.

DA-6 and DA-7 are new compounds that have not been disclosed in the literature, and the synthesis method is described in detail below.

(Monomer Synthesis Example 1; Synthesis of DA-6)

DA-6 was synthesized according to the route shown below.

[Formula 12]

3-(4-nitrophenoxy)propan-1-ol (manufactured by Chemieliva Pharmaceutical, 16.0 g, 81.1 mmol) was dissolved by adding dichloromethane (320 g) and then cooled under ice cooling. To this, triethylamine (12.3 g, 122 mmol), methanesulfonyl chloride (9.76 g, 85.2 mmol), and 4-dimethylaminopyridine (1.0 g, 8.1 mmol) were added, and stirred at room temperature for 15 hours. reacted. Pure water (160 g) was added to the reaction solution, the organic layer was recovered by separation, the liquid was separated and washed with 1N hydrochloric acid (80 g) and pure water (80 g) in that order, and the organic layer was concentrated to obtain DA-6-1. (Yield 20.8 g, 75.4 mmol, yield 93%).

[Formula 13]

To 2,6-dihydroxynaphthalene (5.00 g, 31.2 mmol), NMP (50 g), DA-6-1 (18.9 g, 68.7 mmol) and potassium carbonate (10.8 g, 78 mmol) were added, The reaction was stirred at 100°C for 18 hours. Crystals were precipitated by adding pure water (100 g) to the reaction solution. The obtained crystals were separated by filtration, washed for repulp with pure water, then DMF (500 g) was added to completely dissolve at 100°C and crystallized with methanol/water (1:1, volume ratio) to obtain DA-6-2 ( Quantity 15.2 g, 29.3 mmol, yield 94%).

[Formula 14]

For DA-6-2 (5.00 g, 9.64 mmol), DMF (50 g) and carbon-supported palladium (5% Pd carbon powder (50% water-containing product) K type, manufactured by N E Camcat Co., Ltd., 0.50 g ) was added and stirred for 12 hours at 80°C in a hydrogen atmosphere and under pressurized conditions (0.3 MPa). Since crystals had precipitated, DMF (100 g) was added, and the carbon-supported palladium was removed by filtration. IPA (150 g) was added to the obtained filtrate and crystallized to obtain DA-6 (amount 3.76 g, 8.20 mmol, yield 85%).

(Monomer Synthesis Example 2; Synthesis of DA-7)

DA-7 was synthesized according to the route shown below.

[Formula 15]

In a 500 mL four-necked flask, p-xylylenedichloride (7.0 g, 40 mmol) was dissolved in DMAc (140 g), 4-nitro-m-cresol (12.8 g, 84 mmol) and potassium carbonate (16.5 mmol). g, 120 mmol) was added and stirred at 90°C for 3 hours to cause reaction. After the reaction solution was cooled to room temperature, pure water (280 g) was added while stirring to precipitate crystals. The obtained crystals were separated by filtration, and the cake was washed in that order with pure water, THF, and acetonitrile (35 g each). After that, DA-7-1 was obtained by drying under reduced pressure at 40°C (yield: 15.5 g, 38 mmol, white solid, yield: 95%). From the ¹ H-NMR results shown below, it was confirmed that this solid was DA-7-1.

[Formula 16]

Under a nitrogen atmosphere, DA-7-1 (15.5 g, 38 mmol) obtained above, DMF (466 g), and carbon-supported platinum (3% Pt carbon powder (50% hydrated product)) were added to a 1 L four-necked flask. , manufactured by Evonik, 1.5 g) was added and replaced with a hydrogen atmosphere, followed by stirring at 50°C for 18 hours to cause reaction. After completion of the reaction, the carbon-supported platinum was removed using a membrane filter, and the filtrate was concentrated. IPA (150 g) was added to precipitate crystals, and after stirring at room temperature, the crystals were separated by filtration. The obtained crystals were cake-washed with IPA (75 g) and dried under reduced pressure at 40°C to obtain DA-7 (yield: 10.8 g, 31 mmol, gray solid, yield: 81%). From the ¹ H-NMR results shown below, it was confirmed that this solid was DA-7.

[Synthesis of polymer]

<Synthesis Example 1>

DA-3 (0.541 g, 5.00 mmol), DA-1 (1.60 g, 5.00 mmol) and NMP (15.7 g) were added to a 50 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, and nitrogen was added. It was dissolved by stirring at room temperature. After that, CA-1 (2.15 g, 9.60 mmol) and NMP (15.8 g) were added and stirred at 40°C for 24 hours to obtain a solution of polyamic acid (PAA-1) with a solid content concentration of 12% by mass. The Mn of this polyamic acid was 13,500 and the Mw was 39,800.

<Synthesis Example 2>

DA-3 (0.541 g, 5.00 mmol), DA-2 (1.98 g, 5.00 mmol) and NMP (18.5 g) were added to a 50 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, and nitrogen was added. It was dissolved by stirring at room temperature. After that, CA-1 (2.15 g, 9.60 mmol) and NMP (15.8 g) were added and stirred at 40°C for 24 hours to obtain a solution of polyamic acid (PAA-2) with a solid content concentration of 12% by mass. The Mn of this polyamic acid was 14,600 and the Mw was 45,600.

<Synthesis Example 3>

DA-3 (0.541 g, 5.00 mmol), DA-4 (1.46 g, 5.00 mmol) and NMP (14.7 g) were added to a 50 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, and nitrogen was added. It was dissolved by stirring at room temperature. After that, CA-1 (2.15 g, 9.60 mmol) and NMP (15.8 g) were added and stirred at 40°C for 24 hours to obtain a solution of polyamic acid (PAA-3) with a solid content concentration of 12% by mass. The Mn of this polyamic acid was 10,900 and the Mw was 29,700.

<Synthesis Example 4>

DA-3 (0.541 g, 5.00 mmol), DA-5 (1.22 g, 5.00 mmol) and NMP (12.9 g) were added to a 50 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, and nitrogen was added. It was dissolved by stirring at room temperature. After that, CA-1 (2.12 g, 9.45 mmol) and NMP (15.5 g) were added and stirred at 40°C for 24 hours to obtain a solution of polyamic acid (PAA-4) with a solid content concentration of 12% by mass. The Mn of this polyamic acid was 11,200 and the Mw was 28,500.

<Synthesis Example 5>

DA-3 (0.541 g, 5.00 mmol), DA-6 (2.29 g, 5.00 mmol) and NMP (20.8 g) were added to a 50 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, and nitrogen was added. It was dissolved by stirring at room temperature. After that, CA-1 (2.15 g, 9.60 mmol) and NMP (15.8 g) were added and stirred at 40°C for 24 hours to obtain a solution of polyamic acid (PAA-5) with a solid content concentration of 12% by mass. The Mn of this polyamic acid was 18,400 and the Mw was 139,800.

<Synthesis Example 6>

DA-3 (0.541 g, 5.00 mmol), DA-7 (1.74 g, 5.00 mmol) and NMP (16.7 g) were added to a 50 mL four-necked flask equipped with a stirring device and a nitrogen inlet tube, and nitrogen was added. It was dissolved by stirring at room temperature. After that, CA-1 (2.13 g, 9.49 mmol) and NMP (15.6 g) were added and stirred at 40°C for 24 hours to obtain a solution of polyamic acid (PAA-6) with a solid content concentration of 12% by mass. The Mn of this polyamic acid was 11,900 and the Mw was 30,400.

Table 1 shows the specifications of the polyamic acid solution obtained in the above synthesis example. In Table 1, the values in parentheses for the tetracarboxylic acid component and the diamine component represent the usage amount (molar parts) of each tetracarboxylic acid component and each diamine component relative to 100 mole parts of the total amount of the diamine component used in each polymerization process. indicates.

[Preparation of liquid crystal aligning agent]

<Example 1>

NMP (14.0 g) and BCS (6.00 g) were added to the solution (10.0 g) of polyamic acid (PAA-1) obtained in the above Synthesis Example 1, and stirred at room temperature for 30 minutes to prepare a liquid crystal aligning agent (AL-1). got it

<Examples 2 to 3, Comparative Examples 1 to 3>

Liquid crystal aligning agents (AL-2) to (AL- 6) obtained.

The specifications of the liquid crystal aligning agents obtained in the above examples and comparative examples are shown in Table 2.

Abnormalities such as cloudiness and precipitation were not observed in the liquid crystal aligning agents (AL-1) to (AL-6) obtained as described above, and it was confirmed that they were uniform solutions. Using the obtained liquid crystal aligning agent, evaluation of the in-plane uniformity of contrast and evaluation of the water contact angle were performed.

[Manufacture of liquid crystal cell]

The liquid crystal cell was manufactured in the order shown below using the liquid crystal aligning agent obtained above. After filtering the liquid crystal aligning agent through a filter with a pore diameter of 1.0 μm, it is applied to a glass substrate (40 mm long x 30 mm wide x 0.7 mm thick) on which an ITO electrode is formed by a spin coat method, and is applied on a hot plate at 80°C for 60 °C. After drying for a second, baking was performed in a 230 degreeC infrared heating furnace for 20 minutes, and the liquid crystal alignment film with a film thickness of 100 nm was formed. Orientation treatment is performed by irradiating either 400 mJ/cm ² , 600 mJ/cm ² , or 800 mJ/cm ² with linearly polarized ultraviolet rays with a wavelength of 254 nm at an extinction ratio of 26:1 through a polarizer on the coated film surface, It was baked again in an infrared heating furnace at 230 degreeC for 30 minutes, and the board|substrate (1st glass substrate) on which the liquid crystal alignment film was formed was obtained. A substrate with a liquid crystal alignment film (second glass substrate) was obtained in the same manner as above except that the alignment treatment was performed so that the orientation direction was perpendicular to the first glass substrate. The above two substrates are made into a set, and a bead spacer with a diameter of 4 ㎛ (Nikki Catalyst Chemical Company, Jinsa Ball, SW-D1) with a diameter of 4 μm is applied on one liquid crystal alignment film, leaving a liquid crystal injection port. A sealant (XN-1500T, manufactured by Mitsui Chemicals Co., Ltd.) was printed around the substrate, and another board was bonded so that the orientation direction in which the liquid crystal alignment film surface faces was 0°. After that, heat treatment was performed at 150°C for 60 minutes to cure the sealant and 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 a liquid crystal cell was obtained. After that, the obtained liquid crystal cell was heated at 120°C for 1 hour and then used for evaluation.

[Evaluation of in-plane uniformity of contrast]

The variation in the twist angle of the liquid crystal cell was evaluated using AxoStep manufactured by AXOMETRICS. The liquid crystal cell manufactured above was installed on a measurement stage, and the distribution of circular retardance within the pixel plane was measured in a state without voltage being 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, the case where the 3σ value was 3.00 or less was designated as “○”, the case where the 3σ value was greater than 3.00 and 5.00 or less was designated as “Δ”, and the case where the 3σ value was greater than 5.00 was designated as “×”. The results are shown in Table 3.

[Evaluation of water contact angle]

After filtering the liquid crystal aligning agent obtained above through a filter with a pore diameter of 1.0 μm, it was applied by spin coating to a glass substrate (40 mm long x 30 mm wide x 1.1 mm thick) on which ITO electrodes were formed, and then heated in a hot bath at 80°C. After drying on the plate for 60 seconds, baking was performed in an infrared heating furnace at 230°C for 20 minutes to form a liquid crystal alignment film with a film thickness of 100 nm. This coated film surface was irradiated with 500 mJ/cm ² of linearly polarized ultraviolet rays with a wavelength of 254 nm at an extinction ratio of 26:1 through a polarizing plate, and then baked in an infrared heating furnace at 230°C for 30 minutes to obtain a substrate with a liquid crystal alignment film. . For this substrate, the contact angle of water was measured using a fully automatic contact angle meter (DM-701, manufactured by Kyowa Interface Science Co., Ltd.). As an evaluation standard, the case where the water contact angle was greater than 50° was designated as “○”, and the case where the water contact angle was 50° or less was designated as “×”. The results are shown in Table 3.

As shown in Table 3, the liquid crystal aligning film obtained using the liquid crystal aligning agent (AL-1), (AL-2), and (AL-6) of Examples 1-3 is the liquid crystal aligning agent of Comparative Examples 1-3. Compared to the liquid crystal alignment film obtained using (AL-3) to (AL-5), good in-plane uniformity was shown in a wide exposure amount range, and the water contact angle was increased.

Industrial applicability

The liquid crystal aligning film obtained from the liquid crystal aligning agent of the present invention is widely used in liquid crystal display elements of various operation modes, for example, a liquid crystal aligning film for a retardation film, a liquid crystal aligning film for a scanning antenna or a liquid crystal array antenna, or a transmission and scattering type. It can also be used for the liquid crystal alignment film for liquid crystal light control elements.

The liquid crystal display element of the present invention can be effectively applied to devices having various functions, for example, liquid crystal televisions, watches, portable games, word processors, notebook computers, car navigation systems, camcorders, PDAs, and digital devices. It can be used in cameras, mobile phones, smartphones, various monitors, information displays, etc.

In addition, the entire contents of the specification, claims, drawings, and abstract of Japanese Patent Application No. 2021-177004 filed on October 28, 2021, and the specification of Japanese Patent Application No. 2021-189679 filed on November 22, 2021, The entire contents of the claims, drawings and abstract are hereby incorporated by reference and are hereby accepted as disclosure of the specification of the present invention.

Claims (13)

At least one type of polymer (P) selected from the group consisting of a polyimide precursor obtained using a diamine component containing diamine (0) represented by the following formula ( _DA ) and a polyimide that is an imidate of the polyimide precursor A liquid crystal aligning agent characterized in that it contains.

(Ar represents a divalent aromatic group of any of a divalent benzene ring, biphenyl structure, or naphthalene ring, and any hydrogen atom on the benzene ring, biphenyl structure, or naphthalene ring may be substituted with a monovalent group. m , n are each independently integers from 1 to 3.
Any hydrogen atom on the benzene ring to which the amino groups at both ends are bonded may be substituted with a monovalent group.) According to claim 1,
Ar is 1,4-phenylene, 1,3-phenylene, 2-methyl-1,4-phenylene, 2-ethyl-1,4-phenylene, 2-propyl-1,4-phenylene , 2-isopropyl-1,4-phenylene, 2-methoxy-1,4-phenylene, 2-ethoxy-1,4-phenylene, 2-propoxy-1,4-phenylene, 2 -Fluoro-1,4-phenylene, 2,3-dimethyl-1,4-phenylene, 4-methyl-1,3-phenylene, 5-methyl-1,3-phenylene, 4-fluoro -1,3-phenylene, 2,3,5,6-tetramethyl-1,4-phenylene, biphenyl-4,4'-diyl, 2-methylbiphenyl-4,4'-diyl, 2 -Ethylbiphenyl-4,4'-diyl, 2-propylbiphenyl-4,4'-diyl, 2-methoxybiphenyl-4,4'-diyl, 2-ethoxybiphenyl-4,4'-diyl , 2-fluorobiphenyl-4,4'-diyl, 3-methylbiphenyl-4,4'-diyl, 3-ethylbiphenyl-4,4'-diyl, 3-propylbiphenyl-4,4' -Diyl, 3-methoxybiphenyl-4,4'-diyl, 3-ethoxybiphenyl-4,4'-diyl, 3-fluorobiphenyl-4,4'-diyl, 2,2'-dimethylbiphenyl -4,4'-diyl, 3,3'-dimethylbiphenyl-4,4'-diyl, biphenyl-3,3'-diyl, 5-methylbiphenyl-3,3'-diyl, 5,5 A liquid crystal aligning agent selected from '-dimethylbiphenyl-3,3'-diyl, 1,5-naphthylene, 2,6-naphthylene, or 1-methyl-2,6-naphthylene. The method of claim 1 or 2,
The liquid crystal aligning agent wherein the diamine (0) is any diamine selected from the group consisting of the following formulas (d _A -1) to (d _A -3).

(In the above formulas (d _A -1) to (d _A -3), any hydrogen atom on the benzene ring to which the amino group at both ends is bonded, the benzene ring to which the alkylene group is bonded, the biphenyl structure, or the naphthalene ring is, m and n each independently have the above definitions.) The method according to any one of claims 1 to 3,
At least one hydrogen atom on the benzene ring to which the amino groups at both ends are bonded is a halogen atom, an alkyl group with 1 to 3 carbon atoms, an alkoxy group with 1 to 3 carbon atoms, a fluoroalkyl group with 1 to 3 carbon atoms, or a fluorine group with 1 to 3 carbon atoms. A liquid crystal aligning agent substituted with a Roalkoxy group. The method according to any one of claims 1 to 4,
Liquid crystal alignment, wherein the polymer (P) is a polymer having at least one type of repeating unit selected from the group consisting of a repeating unit (p1) represented by the following formula (1) and an imidized structural unit of the repeating unit (p1) my.

_{( In} formula ₍ 1), represents a hydrogen atom or a monovalent organic group.) The method according to any one of claims 1 to 5,
The polymer (P) is a tetracarboxylic acid containing the diamine component and acyclic aliphatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, aromatic tetracarboxylic dianhydride, or derivatives thereof. A liquid crystal aligning agent obtained by polycondensation reaction of components. The method according to any one of claims 1 to 6,
A liquid crystal aligning agent whose usage-amount of the said diamine (0) is 5 mol% or more with respect to the said diamine component. The method according to any one of claims 1 to 7,
In addition, it contains at least one type of polymer (B) selected from the group consisting of a polyimide precursor obtained by using a diamine component that does not contain the diamine (0) and a polyimide that is an imidate of the polyimide precursor. Liquid crystal orientation agent. A liquid crystal aligning film obtained from the liquid crystal aligning agent according to any one of claims 1 to 8. A liquid crystal display element comprising the liquid crystal alignment film according to claim 9. A method for manufacturing a liquid crystal display element, comprising the following steps (1) to (3).
Process (1): A process of applying the liquid crystal aligning agent according to any one of claims 1 to 8 on a substrate.
Step (2): A step of baking the applied liquid crystal aligning agent to obtain a film.
Step (3): A step of subjecting the film obtained in step (2) to an orientation treatment. According to claim 11,
A method of manufacturing a liquid crystal display element, wherein the alignment treatment is photo-alignment treatment. Diamine represented by the following formula DA-7.