WO2021060268A1

WO2021060268A1 - Liquid crystal aligning agent for vertical alignment, liquid crystal alignment film, and liquid crystal display element

Info

Publication number: WO2021060268A1
Application number: PCT/JP2020/035773
Authority: WO
Inventors: 慎躍大野; 雄介山本
Original assignee: 日産化学株式会社
Priority date: 2019-09-24
Filing date: 2020-09-23
Publication date: 2021-04-01
Also published as: KR20220069916A; CN114514303A; JPWO2021060268A1; TW202126795A

Abstract

Provided are: a liquid crystal aligning agent that is for forming a liquid crystal alignment film for vertical alignment (VA) and that has a high refractive index and a high light transmittance due to not having any coloration; a liquid crystal alignment film obtained from said liquid crystal aligning agent; and a liquid crystal display element having said liquid crystal alignment film.　This liquid crystal aligning agent for vertical alignment is characterized by containing at least one polymer (P) selected from the group consisting of polyimides and polyimide precursors obtained by using a diamine component including a diamine (0) represented by formula (0). (A and A' each independently represent a single-ring group, a fused-ring group, or a group obtained through binding of two said single-ring groups, and at least one of A and A' represents a fused-ring group. L represents a single bond or -X₁-Q-X₂-. X₁ and X₂ each independently represent a single bond, an oxygen atom, or a sulfur atom. Q represents an alkylene group having 1 or 2 carbon atoms.)

Description

Liquid crystal alignment agent for vertical alignment, liquid crystal alignment film, and liquid crystal display element

The present invention comprises a liquid crystal alignment agent for vertical alignment (VA), a liquid crystal alignment film obtained from the liquid crystal alignment agent, a liquid crystal display element provided with the liquid crystal alignment film, a novel diamine suitable for them, and a heavy weight. Regarding coalescence.

Liquid crystal display elements are widely used from small applications such as mobile phones and smartphones to relatively large applications such as televisions and monitors. The liquid crystal display element is generally configured by arranging a pair of electrode substrates so as to face each other with a predetermined gap (several μm) and enclosing a liquid crystal between the electrode substrates. Then, by applying a voltage between the transparent conductive films constituting each electrode of the electrode substrate, the display on the liquid crystal display element is performed. These liquid crystal display elements have a liquid crystal alignment film that is indispensable for controlling the arrangement state of liquid crystal molecules.

On the other hand, as a liquid crystal display element, various driving methods have been developed in which the electrode structure and the physical characteristics of the liquid crystal molecules used are different. For example, various modes such as TN (Twisted Nematic) method, STN (Super Twisted Nematic) method, VA (Vertical Alignment) method, IPS (In-Plane Switching) method, and FFS (fringe field switching) method are known. ..
Among them, the VA (vertical orientation) type liquid crystal display element has a wide viewing angle, a fast response speed, a large contrast, and the rubbing process can be eliminated in the production process. Therefore, there is a particular need for an increase in size. Widely used mainly for expensive TVs and monitors.

International Publication No. 2008/117615 Japanese Patent Application Laid-Open No. 2008-76950

By the way, the above-mentioned transparent conductive film in the liquid crystal display element is usually formed of a composition (ITO) containing indium oxide as a main component and doped with several% tin oxide, and its refractive index is determined by the liquid crystal alignment film. It has a high value unlike the refractive index of. Therefore, when the light from the display light source is to be transmitted to the electrode substrate, the light is reflected at the interface between the transparent conductive film and the liquid crystal alignment film in each electrode substrate. As a result, the light transmittance of the electrode substrate cannot be sufficiently obtained, which causes a problem that the display brightness is lowered.
In particular, in recent years, ultra-high-definition panels such as 4K and 8K have been developed, but these panels occupy a large amount of black matrix (BM), TFT, etc., and the aperture ratio of the panel decreases. It is important to improve the transmittance of the display unit.

Therefore, the present inventors have formed the transparent conductive film in order to increase the refractive index of the liquid crystal alignment film from the viewpoint that the above-mentioned problems can be solved by reducing the difference between the refractive index of the transparent conductive film and the refractive index of the liquid crystal alignment film. Various materials were examined. Specifically, in order to increase the refractive index of the liquid crystal alignment film, various types of polymers contained in the liquid crystal alignment agent forming the liquid crystal alignment film were searched for.

As a result, by selecting a specific polymer, a liquid crystal alignment film having a refractive index close to that of the transparent conductive film could be obtained, but on the other hand, a liquid crystal alignment film having a high refractive index was formed. It has been clarified that the polymer to be produced has a coloring property in many cases. A liquid crystal alignment film formed from a liquid crystal alignment agent containing a colorable polymer has a low light transmittance and causes a decrease in display brightness, and as a result, the above object is not achieved.

In view of the above circumstances, an object of the present invention is a liquid crystal alignment agent for forming a liquid crystal alignment film for VA (vertical alignment) having a high light transmittance because it has a high refractive index but no coloring property. An object of the present invention is to provide a liquid crystal alignment film obtained from an agent and a liquid crystal display element having the liquid crystal alignment film.

As a result of diligent research to achieve the above object, the present inventor finds that a liquid crystal aligning agent containing a partially novel polymer having a specific structure is effective for achieving the above object. The present invention has been completed.
The present invention is at least one selected from the group consisting of a polyimide precursor obtained by using a diamine component containing a diamine (0) represented by the following formula (0) and a polyimide which is an imide of the polyimide precursor. A liquid crystal alignment agent for vertical alignment (VA), which contains a polymer (P), a liquid crystal alignment film obtained from the liquid crystal alignment agent, and a vertical alignment type liquid crystal display element having the liquid crystal alignment film. It is in.

(A and A'independently represent a monocyclic group, a fused ring group, or a group in which two monocyclic groups are bonded, and at least one of A and A'represents a fused ring group. L represents a single bond or -X _1- Q-X _2- group. X ₁ and X ₂ independently represent a single bond, an oxygen atom or a sulfur atom. Q is 1 carbon or 1 carbon atom or a sulfur atom. Represents 2 alkylene groups.)

According to the present invention, a liquid crystal alignment agent for vertical alignment (VA) that forms a liquid crystal alignment film having a high light transmittance because it has a high refractive index but no coloring property can be obtained. Since the liquid crystal alignment film on which the liquid crystal alignment agent is formed has a high refractive index, the difference between the refractive index of the transparent conductive film in the liquid crystal display element and the refractive index of the liquid crystal alignment film can be reduced, and the difference between the refractive index and the refractive index of the liquid crystal alignment film can be reduced. Since it does not have colorability, it is possible to obtain a vertically oriented (VA) type liquid crystal display element having high light transmission and high display brightness.

As described above, the liquid crystal aligning agent of the present invention is made from a polyimide precursor obtained by using a diamine component containing a diamine (0) represented by the following formula (0) and a polyimide which is an imide of the polyimide precursor. It is characterized by containing at least one polymer (P) selected from the above group.

In the above formula (0), A, A', L, X ₁ and X ₂ are as defined above, respectively.

The monocyclic group in A and A'refers to a divalent group obtained by removing two hydrogen atoms from the monocyclic ring. Examples of the monocycle include benzene; a 5-membered heterocycle such as furan, thiophene, pyrrole, oxazole, thiazole, imidazole, and pyrazole; and a 6-membered heterocycle such as pyran, pyrone, pyridine, pyridazine, pyrimidine, and pyrazine. The single ring is preferably benzene or pyridine. When the monocyclic ring is benzene, the monocyclic group is a phenylene group.

The condensed ring group in A and A'refers to a divalent group obtained by removing two hydrogen atoms from the condensed ring. Examples of the fused ring include condensed polycyclic aromatic hydrocarbons such as naphthalene, tetraline, inden, fluorene, anthracene, phenanthrene and pyrene; benzofuran, thionaphthene, indole, carbazole, coumarin, benzo-pyrone, quinoline, isoquinoline, aclysine, etc. Examples thereof include fused polycyclic heterocycles such as phthalazine, quinazoline and quinoxaline. The fused ring is preferably naphthalene, anthracene, pyrene, indole, carbazole, coumarin, benzo-pyrone, quinoline, or isoquinoline.
The group in which the two monocyclic groups are bonded is preferably a biphenyl structure or a bipyridine group.

Among them, A and A'preferably a phenylene group, a pyridinyl group, a naphthylene group, an anthracenyl group, a quinolinyl group, a biphenyl structure or a bipyridinyl group from the viewpoint of obtaining the effects of the present invention.
L is a single bond, -O- (CH ₂ ) _n- (n is an integer of 1 or 2), or -O- (CH ₂ ) _n- O- (n is an integer of 1 or 2). .) Is preferable.
Specific examples of the diamine (0) represented by the above formula (0) include the following formulas (d-1) to (d-21).

A preferable specific example of the diamine (0) represented by the above formula (0) is a diamine represented by the following formula (1).

In the above formula (1), A, L, X ₁ and X ₂ are as defined above, respectively.

As a preferable specific example of the diamine (1) represented by the above formula (1), among the above formulas (d-1) to (d-21), the formulas (d-1) to (d-7), ( Examples thereof include d-13) to (d-14), (d-17) to (d-18) and (d-21).

The polymer (P) contained in the liquid crystal aligning agent of the present invention is selected from the group consisting of the structures represented by the following formulas (S1) to (S3) in addition to the diamine represented by the above formula (0). It is preferable that the polymer is at least one selected from the group consisting of a polyimide precursor obtained by using a diamine component containing a diamine (s) having at least one kind and a polyimide which is an imide of the polyimide precursor. ..

In the formula [S1], X ¹ and X ² are independently single-bonded,-(CH ₂ ) _a- (a is an integer of 1 to 15), -CONH-, -NHCO-, and -CON. (CH ₃ )-, -NH-, -O-, -COO-, -OCO- or-((CH ₂ ) _a1- A ₁ ) _m1- (a 1 is an integer from 1 to 15, and A ₁ is oxygen. atom or -COO- the stands, if .m ₁ _{m 1} is an integer of 1 or 2 is 2, a plurality of a1 and _{a 1} represent each independently have the definitions). G ¹ and G ² each independently represent a divalent cyclic group selected from a divalent aromatic group having 6 to 12 carbon atoms and a divalent alicyclic group having 3 to 8 carbon atoms. Any hydrogen atom on the cyclic group may be an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, or a fluorine-containing alkoxy group having 1 to 3 carbon atoms. Alternatively, it may be substituted with a fluorine atom. m and n are independently integers of 0 to 3, and the total of m and n is 1 to 6, preferably 1 to 4. R ¹ represents an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an alkoxy alkyl group having 2 to 20 carbon atoms, and any hydrogen atom forming ^{R 1 is substituted with a fluorine atom.} You may.
Examples of the divalent cyclic group in G ¹ and G ² include a cyclopropylene group, a cyclohexylene group and a phenylene group. Any hydrogen atom on these cyclic groups can be an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, or a fluorine-containing alkoxy group having 1 to 3 carbon atoms. It may be substituted with a group or a fluorine atom.

In formula [S2], X ³ is a single bond, _{-CONH-, -NHCO-, -CON (CH 3} )-, _{-NH-, -O-, -CH 2} O-, -COO- or -OCO-. Represents. R ² represents an alkyl group having 1 to 20 carbon atoms or an alkoxy alkyl group having 2 to 20 carbon ^{atoms, and any hydrogen atom forming R 2} may be substituted with a fluorine atom.
Further, R ² is preferably an alkyl group having 3 to 20 carbon atoms or an alkoxyalkyl group having 2 to 20 carbon atoms from the viewpoint of enhancing the liquid crystal orientation.

In formula [S3], X ⁴ represents -CONH-, -NHCO-, -O-, -CH ₂ O-, -OCH _{2-, -COO- or -OCO-.} R ³ represents a structure having a steroid skeleton. Further, R ³ preferably has a structure containing a cholestanyl group, a cholesteryl group or a lanostenyl group.

Preferred specific examples of the formula [S1] include the following formulas [S1-x1] to [S1-x7].

In the above formula, R ¹ is an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an alkoxyalkyl group having 2 to 20 carbon atoms. X ^p is-(CH ₂ ) _a- (a is an integer of 1 to 15), -CONH-, -NHCO-, -CON (CH ₃ )-, _{-NH-, -O-, -CH 2} O-, -CH ₂ OCO-, -COO-, or -OCO-. A ₁ is an oxygen atom or -COO- * (however, the bond with "*" binds to (CH ₂ ) _a2 ), and A ₂ is an oxygen atom * -COO- (however, "*"). a given binding hands _(CH ₂₎ binds to _a2), _{a 3} is 0 or _1, a 1, _{a 2} are each independently an integer of 1 ~ 10, Cy 1 , 4-Cyclohexylene group or 1,4-phenylene group.
As a preferable specific example of the formula [S2], X ³ is any of -O-, -CH ₂ O-, -COO- or -OCO-, and R ² is an alkyl group having 3 to 20 carbon atoms or an alkyl group. preferably if an alkoxyalkyl group having 2 to 20 carbon atoms, more preferably R ² is an alkyl group having 3 to 20 carbon atoms, any hydrogen atoms that form the R ² is substituted with a fluorine atom May be good.

A preferable specific example of the above formula [S3] is the following formula [S3-x]. In the formula [S3-x], X is the formula [X1], the formula [X2] or [X3], and Col is the formula [Col1], the formula [Col2] or the formula [Col3], and G Is a formula [G1], a formula [G2], a formula [G3], or a formula [G4]. Me represents a methyl group.

Preferred diamines (s) having the structures represented by the above formulas (S1) to (S3) include diamines represented by the following formulas (d1) or (d2).

In the formulas (d1) and (d2), Y represents the side chain structure represented by the above formulas [S1] to [S3], and the two Ys in the formula (d2) may be the same or different. You may be. In addition, X is a single bond, -O-, -C (CH ₃ ) _2- , -NH-, -CO-,-(CH ₂ ) _m- , -SO _2- , -O- (CH ₂ ) _m. _{_{_{_{-O -, - O-C (}}}} CH 3) 2 -, - CO- (CH 2) m -, - NH- (CH 2) m -, - SO 2 - (CH 2) m -, - CONH- ( _{_{CH 2) m -, - CONH-}} (CH 2) m -NHCO -, - COO- (CH 2) m -OCO -, - COO -, - CONH -, - NH- (CH 2) m -NH-, -SO _2- (CH ₂ ) represents _m- SO _2-. m is an integer from 1 to 8.

Preferred specific examples of the diamine of the above formula (d1) include the following formulas (d1-1) to (d1-18).

(N is an integer from 1 to 20.)

Examples of the diamine represented by the above formula (d2) include structures selected from the group consisting of the following formulas (d2-1) to (d2-6).

In the above formula, X ^p1 to X ^p8 ^{are independently synonymous with X p} in the above formulas [S1-x1] to [S1-x6], and X ^s1 to X ^s4 are independent and −O. _{-, - CH 2 O -,} - OCH 2 -, - COO- or -OCO- _indicates, the _{X a ~ X f, -O -} , - NH -, - O- (CH 2) m -O-, -C (CH ₃ ) _2- , -CO-, -COO-, -CONH-,-(CH ₂ ) _m- , -SO _2- , -OC (CH ₃ ) _2- , -CO- (CH) _{_{_{_{2) m -, - NH- (}}}} CH 2) m -, - NH- (CH 2) m -NH -, - SO 2 - (CH 2) m -, - SO 2 - (CH 2) m -SO 2 -, -CONH- (CH ₂ ) _m- , -CONH- (CH ₂ ) _m -NHCO-, or -COO- (CH ₂ ) _m- OCO-, and R ^1a to R ^1h are independent of each other. It represents an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an alkoxyalkyl group having 2 to 20 carbon atoms. m is 1 to 8.

(Production of polymer (P))
The polymer (P) contained in the liquid crystal aligning agent of the present invention contains a diamine component containing the diamine (0), preferably a diamine component containing a diamine (s) in addition to the diamine (0). It is a polyimide precursor obtained by using it, or a polyimide which is an imidized product of the polyimide precursor. Here, the polyimide precursor is a polymer capable of obtaining a polyimide by imidization of a polyamic acid, a polyamic acid ester, or the like.

The polyamic acid (P), which is a polyimide precursor of the polymer (P), is a diamine component containing the diamine (0), preferably a diamine component containing a diamine (s) in addition to the diamine (0). It can be obtained by a polymerization reaction with a tetracarboxylic acid component.
In this case, the amount of the diamine (0) used is preferably 1 to 100 mol%, more preferably 1 to 99 mol%, still more preferably 5 to 95 mol%, based on the diamine component to be reacted with the tetracarboxylic acid component. ..

When diamine (s) is used in addition to the above diamine (0), the amount of diamine (s) used is preferably 1 to 99 mol% with respect to the diamine component to be reacted with the tetracarboxylic acid component, and 1 to 95 mol%. More preferably mol%.

The diamine component used in the production of the polyamic acid (P) may contain diamines other than diamine (0) and diamine (s) (hereinafter, these are also referred to as other diamines). Examples of other diamines are given below, but the present invention is not limited thereto.

Diamines with carboxy groups such as p-phenylenediamine, m-phenylenediamine, 4- (2- (methylamino) ethyl) aniline, 3,5-diaminobenzoic acid, 4,4'-diaminodiphenylmethane, 3,3' -Diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 4,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, 1,2-bis (4-aminophenyl) ethane, 1 , 3-bis (4-aminophenyl) propane, 1,4-bis (4-aminophenyl) butane, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene , 1,2-bis (4-aminophenoxy) ethane, 1,2-bis (4-amino-2-methylphenoxy) ethane, 1,3-bis (4-aminophenoxy) propane, 1,4-bis ( 4-aminophenoxy) butane, 1,5-bis (4-aminophenoxy) pentane, 1,6-bis (4-aminophenoxy) hexane, 4- (2- (4-aminophenoxy) ethoxy) -3- Fluoroaniline, di (2- (4-aminophenoxy) ethyl) ether, 4-amino-4'-(2- (4-aminophenoxy) ethoxy) biphenyl, 2,2'-dimethyl-4,4'-diamino Biphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 1,4-diaminonaphthalene, 1,5-diaminonaphthalene, 2,6-diaminonaphthalene, 2,7-diaminonaphthalene, 2,2'- Bis [4- (4-aminophenoxy) phenyl] propane, 2,2'-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2'-bis (4-aminophenyl) propane, 1 , 3-Bis (4-aminophenethyl) urea and other amine-bonded diamines, diamines represented by the following formulas (a-1) to (a-6), preferably 2- (2,4-diamino) methacrylate. Phenoxy) ethyl, diamine having a photopolymerizable group such as 2,4-diamino-N, N-diallylaniline at the end, diamine having a radical initiation function such as the following formulas (R1) to (R5), 2,6- Diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, the following formulas (z-1) to (z-18), etc. Diami with a heterocycle Diamine having a diphenylamine skeleton such as the following formulas (Dp-1) to (Dp-3), an organosiloxane-containing diamine such as 1,3-bis (3-aminopropyl) -tetramethyldisiloxane, and the following formula (5). Groups such as -1) to (5-11) "-N (D)-" (D represents a protecting group that is desorbed by heating and replaced with a hydrogen atom, and is preferably a tert-butoxycarbonyl group. ), Diamines having an oxazoline structure such as the following formulas (Ox-1) to (Ox-2), diamines described in International Publication No. 2016/125870, and the like.

(D1 indicates an integer of 2 to 10.)

(N represents an integer from 2 to 10.)

(Boc represents a tert-butoxycarbonyl group.)

Among them, p-phenylenediamine, 3,5-diaminobenzoic acid, 4,4'-diaminodiphenylmethane, 4,4'-diaminobenzophenone, 2, 2'-dimethyl-4,4'-diaminobiphenyl, 2- (2,4-diaminophenoxy) ethyl methacrylate, 2,4-diamino-N, N-diallylaniline, according to the above formulas (R1) to (R5). The diamine represented, the diamine represented by the above formulas (z-1) to (z-18), the diamine represented by the above formulas (5-1) to (5-11), the above formula (Ox-1). The diamine represented by (Ox-2) is preferable.
When other diamines are used in addition to the above diamine (0), the amount of the other diamines used is preferably 1 to 99 mol%, more preferably 5 to 9 mol%, based on the total diamine components used. It is 95 mol%.
When other diamines are used in addition to the above diamines (0) and diamines (s), the amount of the diamines (s) used is preferably 98 mol% or less with respect to the diamine component to be reacted with the tetracarboxylic acid component. More preferably, it is 94 mol% or less.

The amount of the other diamine used is preferably 5 to 40 mol%, more preferably 10 to 40 mol%, based on the total diamine component used in the production of the polyamic acid (P).

In the liquid crystal display element using the PSA method or the SC-PVA mode, from the viewpoint of increasing the response speed, 4,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, a diamine having a photopolymerizable group at the end, and the above formula ( One or more of the diamines represented by R1) to (R5) and the diamines represented by the above formulas (z-1) to (z-18) can be used in the production of the polyamic acid (P). The amount used is preferably 1 to 40 mol%, more preferably 5 to 40 mol%, based on the total diamine component used in the production of the polyamic acid (P).

(Tetracarboxylic acid component)
When the polyamic acid (P) is produced, the tetracarboxylic acid component to be reacted with the diamine component is not only tetracarboxylic dianhydride, but also tetracarboxylic acid, tetracarboxylic acid dihalide, tetracarboxylic acid dialkyl ester, or tetracarboxylic dianoxide. Derivatives of tetracarboxylic dianhydride such as acid dialkyl ester dihalide can also be used.

Examples of the tetracarboxylic dianhydride or its derivative include aromatic tetracarboxylic dianhydride, aliphatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, and derivatives thereof. Here, the aromatic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups including at least one carboxy group bonded to the aromatic ring. The aliphatic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups bonded to a chain hydrocarbon structure. However, it does not have to be composed of only a chain hydrocarbon structure, and a part thereof may have an alicyclic structure or an aromatic ring structure.

The alicyclic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups including at least one carboxy group bonded to the alicyclic structure. However, none of these four carboxy groups are bonded to the aromatic ring. Further, it is not necessary to have only an alicyclic structure, and a chain hydrocarbon structure or an aromatic ring structure may be partially provided.

Among them, the tetracarboxylic dianhydride or a derivative thereof is preferably represented by the following formula (T).

However, in the formula (T), X represents a structure selected from the group consisting of the following (x-1) to (x-13).

In the above formula (x-1), R ¹ to R ⁴ independently represent a hydrogen atom, a methyl group, an ethyl group, a propyl group, a chlorine atom or a phenyl group. R ⁵ and R ⁶ each independently represent a hydrogen atom or a methyl group. j and k are independently 0 or 1, respectively, and A ₁ and A ₂ are independently single bonds, ether (-O-), carbonyl (-CO-), ester (-COO-), respectively. ), phenylene, sulfonyl group (-SO ₂ - represents) or amide groups (-CONH-), 2 pieces of _{a 2} may be the same or may be different. * 1 is a bond that binds to one acid anhydride group, and * 2 is a bond that binds to the other acid anhydride group.

Preferred specific examples of the above formulas (x-12) and (x-13) include the following formulas (x-14) to (x-29). * Represents a bond.

As a preferable specific example of the tetracarboxylic dianhydride represented by the above formula (T) or a derivative thereof, X is the above formulas (x-1) to (x-7), (x-11) to (x). The one selected from -13) can be mentioned.

The proportion of the tetracarboxylic dianhydride or its derivative represented by the above formula (T) is preferably 1 mol% or more, more preferably 5 mol% or more, based on 1 mol of the total tetracarboxylic acid component used. Preferably, 10 mol% or more is more preferable.
The tetracarboxylic dianhydride and its derivative used for producing the polyamic acid (P) may contain a tetracarboxylic dianhydride other than the above formula (T) or a derivative thereof.

The polyamic acid (P) is produced by reacting the diamine component and the tetracarboxylic acid component in a solvent (polycondensation). The solvent is not particularly limited as long as the produced polymer dissolves.
Specific examples of the above solvent include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, 1,3-dimethyl. -2-Imidazolidinone can be mentioned. When the polymer has high solvent solubility, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, or the following formulas [D-1] to [D-3] can be used. The indicated solvents can be used.

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

These solvents may be used alone or in combination. Further, even if the solvent does not dissolve the polymer, it may be mixed with the above solvent and used as long as the produced polymer does not precipitate.
When the diamine component and the tetracarboxylic acid component are reacted in a solvent, the reaction can be carried out at an arbitrary concentration, but the concentration of the diamine component and the tetracarboxylic acid component with respect to the solvent is preferably 1 to 50 mass by mass. %, More preferably 5 to 30% by mass. The initial reaction can be carried out at a high concentration and then the solvent can be added.
In the reaction, the ratio of the total number of moles of the diamine component to the total number of moles of the tetracarboxylic acid component (total number of moles of the diamine component / total number of moles of the tetracarboxylic acid component) is 0.8 to 1.2. Is preferable. Similar to a normal polycondensation reaction, the closer the molar ratio is to 1.0, the larger the molecular weight of the specific polymer produced.

The polyamic acid ester which is a polyimide precursor is, for example, [I] a method of reacting a polyamic acid obtained by the above synthesis reaction with an esterifying agent, [II] a method of reacting a tetracarboxylic acid diester with a diamine, [II] a method of reacting a tetracarboxylic acid diester with a diamine. III] It can be obtained by a known method such as a method of reacting a tetracarboxylic acid diester dihalide with a diamine.

[Polyimide]
The polyimide contained in the liquid crystal alignment agent of the present invention is a polyimide obtained by ring-closing the above-mentioned polyimide precursor. In polyimide, the ring closure rate (also referred to as imidization rate) of the amic acid group does not necessarily have to be 100%, and can be arbitrarily adjusted according to the application and purpose.

Examples of the method of imidizing the polyimide precursor to obtain polyimide include thermal imidization in which the solution of the polyimide precursor is heated as it is, or catalytic imidization in which a catalyst is added to the solution of the polyimide precursor. The temperature at which the polyimide precursor is thermally imidized in the solution is 100 to 400 ° C., preferably 120 to 250 ° C., and it is preferable to remove the water generated by the imidization reaction from the outside of the system.

The catalytic imidization of the polyimide precursor can be carried out by adding a basic catalyst and an acid anhydride to the solution of the polyimide precursor and stirring at −20 to 250 ° C., preferably 0 to 180 ° C. The amount of the basic catalyst is 0.5 to 30 mol times, preferably 2 to 20 mol times, that of the amic acid group, and the amount of acid anhydride is 1 to 50 mol times, preferably 3 to 30 mol times that of the amic acid group. It is double. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, and tributylamine trioctylamine. Among them, pyridine is preferable because it has an appropriate basicity for advancing the reaction. Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, pyromellitic anhydride and the like. Among them, acetic anhydride is preferable because it facilitates purification after the reaction is completed. The imidization rate by catalytic imidization can be controlled by adjusting the amount of catalyst, the reaction temperature, and the reaction time.

When recovering the produced polyimide from the reaction solution for imidization of the polyimide precursor, the reaction solution may be added to a solvent for precipitation. Examples of the solvent used for precipitation include methanol, ethanol, isopropyl alcohol, acetone, hexane, butyl cellsolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, toluene, benzene, water and the like. The polymer which has been put into a solvent and precipitated can be collected by filtration and then dried at normal temperature or by heating under normal pressure or reduced pressure. Further, by repeating the operation of redistributing the polymer recovered by precipitation in a solvent and recovering by reprecipitation 2 to 10 times, impurities in the polymer can be reduced. Examples of the solvent at this time include alcohols, ketones hydrocarbons, and the like, and it is preferable to use three or more kinds of solvents selected from these because the purification efficiency is further improved.

The polystyrene-equivalent weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) of the polyimide precursor and the polyimide is preferably 1,000 to 500,000, more preferably 2,000 to 300,000. Is. The molecular weight distribution (Mw / Mn) represented by the ratio of Mw to the polystyrene-equivalent number average molecular weight (Mn) measured by GPC is preferably 15 or less, more preferably 10 or less. Within such a molecular weight range, good orientation of the liquid crystal display element can be ensured.

(Liquid crystal alignment agent)
The liquid crystal alignment agent of the present invention is a liquid composition in which the polymer (P) and other components used as needed are preferably dispersed or dissolved in a suitable solvent.

In the liquid crystal alignment agent of the present invention, for the purpose of improving, for example, electrical properties, vertical orientation, and solution properties, in addition to the polymer (P), other polymers (hereinafter, other polymers) are also used. ) May be contained. As a specific example of the other polymer, at least one selected from the group consisting of the structures represented by the above formulas (S1) to (S3) in addition to the above polymer (P) from the viewpoint of enhancing the vertical orientation. It may contain at least one polymer selected from the group consisting of a polyimide precursor obtained by using a diamine component containing a seed-bearing diamine and a polyimide which is an imide of the polyimide precursor.
The content ratio of the other polymers is preferably 90 parts by mass or less, more preferably 10 to 90 parts by mass, and further 20 to 80 parts by mass with respect to 100 parts by mass of the total amount of the polymers contained in the liquid crystal alignment agent. preferable.

Other polymers are not particularly limited, and are main skeletons such as polyimide precursors, polyimides, polysiloxanes, polyesters, polyamides, cellulose derivatives, polyacetals, polystyrene derivatives, poly (styrene-phenylmaleimide) derivatives, and poly (meth) acrylates. Can be mentioned. Among them, at least one selected from the group consisting of polyimide precursors, polyimides, polyamides, polyorganosiloxanes, poly (meth) acrylates and polyesters is preferable. Among them, at least one selected from the group consisting of polyimide precursors, polyimides and polysiloxanes is more preferable. In addition, other polymers may be used in combination of 2 or more types.

The liquid crystal alignment agent of the present invention may contain other components other than the above, if necessary. Examples of the component include a crosslinkable compound having at least one substituent selected from an epoxy group, an isocyanate group, an oxetanyl group, a cyclocarbonate group, a blocked isocyanate group, a hydroxy group and an alkoxy group, and a polymerizable unsaturated group. At least one compound selected from the group consisting of crosslinkable compounds having a functional group, a functional silane compound, a metal chelate compound, a curing accelerator, a surfactant, an antioxidant, a sensitizer, an antiseptic, and a dielectric of a liquid crystal alignment film. Examples include compounds for adjusting the rate and electrical resistance.
Preferred specific examples of the crosslinkable compound include compounds represented by the following formulas (CL-1) to (CL-11). Examples of the compound for adjusting the dielectric constant and the electric resistance of the liquid crystal alignment film include monoamines having a nitrogen-containing aromatic heterocycle such as 3-picorylamine.

Examples of the organic solvent used in the liquid crystal alignment agent of the present invention include N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N-ethyl-2-pyrrolidone, and N- (n-propyl). -2-Pyrrolidone, N-isopropyl-2-pyrrolidone, N- (n-butyl) -2-pyrrolidone, N- (tert-butyl) -2-pyrrolidone, N- (n-pentyl) -2-pyrrolidone, N -Methoxypropyl-2-pyrrolidone, N-ethoxyethyl-2-pyrrolidone, N-methoxybutyl-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone, 3-methoxy-N, N-dimethylpropanamide, 3-butoxy- N, N-dimethylpropanamide, γ-butyrolactone, γ-butyrolactam, N, N-dimethylformamide, N, N-dimethylacetamide, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monomethyl ether, butyl lactate, Butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, butyl 3-methoxypropionate, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene Glycol-n-propyl ether, ethylene glycol-i-propyl ether, ethylene glycol monobutyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol diacetate, diethylene glycol dimethyl ether , Diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, diisobutylcarbinol (2,6-dimethyl-4-heptanol) , Diisobutylketone, isoamylpropionate, isoamylisobutyrate, diisopentyl ether, ethylene carbonate, propylene carbonate and the like. These can be used by mixing two or more kinds.

The solid content concentration in the liquid crystal alignment agent (the ratio of the total mass of the components other than the solvent of the liquid crystal alignment agent to the total mass of the liquid crystal alignment agent) is appropriately selected in consideration of viscosity, volatility, etc., but is preferable. It is in the range of 1 to 10% by mass. From the viewpoint of forming a uniform and defect-free coating film, 1% by mass or more is preferable, and from the viewpoint of storage stability of the solution, 10% by mass or less is preferable. A particularly preferable concentration of the polymer is 2 to 8% by mass.

<Liquid crystal alignment film>
The liquid crystal alignment film for vertical alignment using the liquid crystal alignment agent of the present invention can be produced by sequentially performing the steps of applying, drying and firing the above liquid crystal alignment agent on a substrate. The substrate used at this time is not particularly limited as long as it is a highly transparent substrate, and in addition to the glass substrate, a plastic substrate such as an acrylic substrate or a polycarbonate substrate can also be used. From the viewpoint of process simplification, it is preferable to use a substrate on which an ITO electrode or the like for driving a liquid crystal is formed. Further, in the reflective liquid crystal display element, an opaque substrate such as a silicon wafer can be used if only one substrate is used, and a material that reflects light such as aluminum can also be used as the electrode in this case.

Examples of the method for applying the liquid crystal alignment agent include screen printing, offset printing, flexographic printing inkjet method, dip method, roll coater method, slit coater method, spinner method, and spray method. From the viewpoint of enhancing, a method of applying by flexographic printing or an inkjet method is preferable.

After applying the liquid crystal alignment agent on the substrate, it is dried at 40 to 150 ° C. by a heating means such as a hot plate or a heat circulation type oven IR (infrared) type oven, depending on the solvent used for the liquid crystal alignment agent. Then, the liquid crystal alignment film can be obtained by firing at a temperature of preferably 150 to 300 ° C., more preferably 180 to 250 ° C.

If the thickness of the liquid crystal alignment film after firing is too thick, it is disadvantageous in terms of power consumption of the liquid crystal display element, and if it is too thin, the reliability of the liquid crystal display element may decrease. Therefore, it is preferably 5 to 300 nm, more preferably. Is 10 to 100 nm.

<Liquid crystal display element>
The liquid crystal display element of the present invention includes the liquid crystal alignment film.
In the VA type liquid crystal display element, the coating film formed as described above can be used as it is as a liquid crystal alignment film, but if necessary, a rubbing treatment or a PSA treatment described later may be performed.

The liquid crystal aligning agent of the present invention has a liquid crystal composition having a liquid crystal layer between a pair of substrates provided with electrodes, and contains a polymerizable compound polymerized by at least one of active energy rays and heat between the pair of substrates. It is also preferably used for a liquid crystal display element manufactured through a step of arranging an object and polymerizing a polymerizable compound by at least one of irradiation and heating of active energy rays while applying a voltage between electrodes. Here, the voltage to be applied can be, for example, a direct current or an alternating current of 5 to 50 V. Further, as the active energy ray, ultraviolet rays are suitable. The ultraviolet rays include ultraviolet rays having a wavelength of 300 to 400 nm, preferably ultraviolet rays having a wavelength of 310 to 360 nm. The irradiation amount of light is preferably 0.1 to 20 J / cm ² , and more preferably 1 to 20 J / cm ² .

As a method for manufacturing a liquid crystal display element using the liquid crystal alignment agent of the present invention, for example, the above liquid crystal alignment agent is applied onto a pair of substrates having a conductive film to form a coating film, and a coating film is formed through a layer of liquid crystal molecules. There is a method in which the liquid crystal cells are arranged so as to face each other so that the coating films are opposed to each other, and the liquid crystal cells are irradiated with light in a state where a voltage is applied between the conductive films of the pair of substrates.

The above liquid crystal display element controls the pre-tilt of liquid crystal molecules by the PSA (Polymer Sustained Alignment) method. In the PSA method, a small amount of a photopolymerizable compound, for example, a photopolymerizable monomer is mixed in a liquid crystal material, a liquid crystal cell is assembled, and then an ultraviolet ray is applied to the photopolymerizable compound in a state where a predetermined voltage is applied to the liquid crystal layer. The pretilt of the liquid crystal molecules is controlled by the polymer produced by irradiating the liquid crystal molecules. Since the orientation state of the liquid crystal molecules when the polymer is formed is memorized even after the voltage is removed, the pretilt of the liquid crystal molecules can be adjusted by controlling the electric field or the like formed in the liquid crystal layer. Further, since the PSA method does not require a rubbing process, it is suitable for forming a vertically oriented liquid crystal layer in which it is difficult to control the pre-tilt by the rubbing process.

The liquid crystal display element of the present invention is a liquid crystal display element obtained by obtaining a substrate with a liquid crystal alignment film from the liquid crystal alignment agent of the present invention by the above-mentioned method, and then producing a liquid crystal cell by a known method.
As a method for producing a liquid crystal cell, a pair of substrates on which a liquid crystal alignment film is formed is prepared, a spacer is sprayed on the liquid crystal alignment film of one substrate, the liquid crystal alignment film surface is on the inside, and the other is produced. Examples thereof include a method in which the substrates of the above are bonded and the liquid crystal is injected under reduced pressure to seal the liquid crystal, and a method in which the liquid crystal is dropped on the liquid crystal alignment film surface on which the spacer is sprayed and then the substrates are bonded and sealed.

As described above, the liquid crystal may be mixed with a polymerizable compound that polymerizes by ultraviolet irradiation or heat. The polymerizable compound is a compound having at least one polymerizable unsaturated group such as an acrylate group or a methacrylate group in the molecule, for example, a polymerizable compound represented by the following formulas (M-1) to (M-3). Compounds can be mentioned.

At that time, the content of the polymerizable compound is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the liquid crystal component. If the amount of the polymerizable compound is less than 0.01 parts by mass, the polymerizable compound does not polymerize and the orientation of the liquid crystal cannot be controlled. If the amount is more than 10 parts by mass, the number of unreacted polymerizable compounds increases and the liquid crystal display element. The seizure characteristics of the polymer are reduced. After producing the liquid crystal cell, the polymerizable compound is polymerized by irradiating the liquid crystal cell with heat or ultraviolet rays while applying an AC / DC voltage to the liquid crystal cell. Thereby, the orientation of the liquid crystal molecules can be controlled.

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 that polymerizes between the pair of substrates by at least one of active energy rays and heat. It may also be used in a liquid crystal display element manufactured through a step of arranging an alignment film and applying a voltage between electrodes, that is, in SC-PVA mode. Here, ultraviolet rays are suitable as the active energy rays. As the ultraviolet rays, the ultraviolet rays used in the PSA method can be applied including a preferable embodiment. In the case of polymerization by heating, the heating temperature is 40 to 120 ° C, preferably 60 to 80 ° C. Further, ultraviolet rays and heating may be performed at the same time.

In order to obtain a liquid crystal alignment film containing a polymerizable group that polymerizes from at least one of active energy rays and heat, a method of adding a compound containing this polymerizable group to a liquid crystal aligning agent or a polymer containing a polymerizable group A method using an ingredient can be mentioned. Specific examples of the polymer containing a polymerizable group include a polymer obtained by using a diamine having a function of polymerizing by the above-mentioned light irradiation.

The present invention will be specifically described below with reference to examples, but the present invention is not construed as being limited to these examples. In the following, the abbreviations of the compounds and the measurement method of each property are as follows. Unless otherwise specified, the numerical values are based on mass.

(Boc represents a tert-butoxycarbonyl group.)

(Tetracarboxylic dianhydride)

(Organic solvent)
NMP: N-methyl-2-pyrrolidone, BCS: Butyl cellosolve THF: tetrahydrofuran

[viscosity]
For the viscosity of the polyamic acid solution, etc., use an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.), sample volume 1.1 mL (milliliter), cone rotor TE-1 (1 ° 34', R24), temperature 25. Measured at ° C.

[Measurement of molecular weight]
The molecular weight of the polyimide precursor and the polyimide can be determined by using a room temperature gel permeation chromatography (GPC) apparatus (GPC-101) (manufactured by Showa Denko) and a column (KD-803, KD-805) (manufactured by Shodex). It was measured as follows.
Column temperature: 50 ° C
Eluent: N, N-dimethylformamide (as an additive, lithium bromide monohydrate (LiBr · H ₂ O) is 30 mmol / L (liter), phosphoric acid / anhydrous crystal (o-phosphoric acid) is 30 mmol / L. L, tetrahydrofuran (THF) is 10 ml / L)
Flow velocity: 1.0 ml / min Standard sample for preparing a calibration curve: TSK standard polyethylene oxide (molecular weight; about 900,000, 150,000, 100,000 and 30,000) (manufactured by Tosoh Corporation) and polyethylene glycol (molecular weight; about) 12,000, 4,000 and 1,000) (manufactured by Polymer Laboratory).

[Measurement of imidization rate]
20 mg of polyimide powder is placed in an NMR (nuclear magnetic resonance) sample tube (NMR sampling tube standard, φ5 (manufactured by Kusano Kagaku Co., Ltd.)) and deuterated dimethyl sulfoxide (DMSO-d 6,0.05 mass% TMS (tetramethylsilane)). (Mixed product) (0.53 ml) was added and ultrasonically applied to completely dissolve. This solution was measured for proton NMR at 500 MHz with an NMR measuring machine (JNW-ECA500) (manufactured by JEOL Datum). The imidization rate is determined by using a proton derived from a structure that does not change before and after imidization as a reference proton, and the peak integrated value of this proton and the proton peak derived from the NH group of amic acid appearing in the vicinity of 9.5 to 10.0 ppm. It was calculated by the following formula using the integrated value.
Imidization rate (%) = (1-α · x / y) × 100
In the above formula, x is the integrated proton peak value derived from the NH group of amic acid, y is the integrated peak value of the reference proton, and α is one NH group proton of the amic acid in the case of polyamic acid (imidization rate is 0%). It is the number ratio of the reference protons to.

<Synthesis example of compound [DA-n-2]>
Compound [DA-n-2] was synthesized according to the following scheme.

(Synthesis of compound [1])
To dimethylformamide (1050 g), 6-bromonaphthalene-2-ol (150 g, 672 mmol) was added, and the mixture was cooled under ice-cooling. Sodium hydride (60%, 29.6 g) was added little by little, and the mixture was stirred under ice-cooling for 1 hour, benzyl bromide (121 g) was added, and the mixture was stirred at room temperature for 1 hour. Further, under water cooling, pure water (750 g) is added little by little and stirred to precipitate crystals, filtered, and the filter is slurry-washed with methanol (750 g), filtered, and the filter is dried to produce a compound [ 1] was obtained (yield: 207 g, yield: 98%, white crystals).
^{1 1} H-NMR (400 MHz, DMSO-d ₆ , δ (ppm)): 8.13 (d, 1H, J = 2.0 Hz), 7.85 (d, 1H, J = 9.2 Hz), 7. 78 (d, 1H, J = 8.8Hz), 7.58 (dd, 1H, J = 8.8Hz, 2.4Hz), 7.53-7.48 (m, 3H), 7.44-7 .40 (m, 2H), 7.38-7.33 (m, 1H), 7.30 (dd, 1H, J = 9.0Hz, 2.6Hz), 5.22 (s, 2H).

(Synthesis of compound [2])
To tetrahydrofuran (1000 g), tert-butoxysodium (82.6 g) and benzophenone imine (126 g) were added, and the mixture was stirred at room temperature for 30 minutes. Compounds [1] (207 g, 661 mmol), Pd ₂ (dba) ₃ (tris (dibenzylideneacetone) dipalladium (0), 3.03 g) and BINAP (2,2'-bis (diphenylphosphino)- 1,1'-binaphthyl (6.17 g) was added, and the mixture was stirred at 65 ° C. for 23 hours under a nitrogen atmosphere. After cooling to room temperature, 1N hydrochloric acid (1000 g) was added, and the mixture was stirred at room temperature for 15 minutes to separate the aqueous layer. Further, ethyl acetate (200 g), hexane (100 g) and 1N hydrochloric acid (500 g) were added to the organic layer, and the mixture was added to the separated aqueous layer. Under water cooling, sodium hydroxide (80 g) was added to make it alkaline. The organic layer was separated, washed with saturated aqueous sodium chloride solution, dried over sodium sulfate, filtered, and the filtrate was concentrated to obtain a crude product (154 g). Ethyl acetate (462 g) was added to the crude product to dissolve it by heating at 70 ° C., and then hexane (770 g) was added to cool the crude product. Then, this was filtered and the filter medium was dried to obtain compound [2] (yield: 124 g, yield: 74%, light brown crystals).
^{1 1} H-NMR (400 MHz, DMSO-d ₆ , δ (ppm)): 7.50-7.43 (m, 4H), 7.42-7.37 (m, 2H), 7.35-7. 30 (m, 1H), 7.19 (d, 1H, J = 2.8Hz), 7.04 (dd, 1H, J = 8.8Hz, 2.8Hz), 6.90 (dd, 1H, J) = 8.8Hz, 2.0Hz), 6.80 (d, 1H, J = 2.0Hz), 5.13 (br, 4H).

(Synthesis of compound [3])
Compound [2] (124 g, 497 mmol) and di-tert-butyl dicarbonate (130 g) were added to dichloromethane (1000 g), and the mixture was stirred at room temperature for 20 hours. Since the reaction was not completed, di-tert-butyl dicarbonate (10 g) was additionally added, and the mixture was further stirred at room temperature for 20 hours. Saturated aqueous sodium hydrogen carbonate solution (1 L) and dichloromethane (300 g) were added and separated. The organic layer was washed in the order of pure water (450 mL) and saturated aqueous sodium chloride solution (300 mL), dried over sodium sulfate, filtered, and the filtrate was concentrated to obtain a crude product (198 g). Ethyl acetate (600 g) was added to the crude product to dissolve it by heating at 70 ° C., and then hexane (1000 g) was added and cooled. Then, this was filtered and the filter medium was dried to obtain compound [3] (yield: 142 g, yield: 82%, white crystals).
^{1 1} H-NMR (400 MHz, DMSO-d ₆ , δ (ppm)): 9.46 (s, 1H), 8.02 (s, 1H), 7.69 (t, 2H, J = 8.6 Hz) , 7.52-7.49 (m, 2H), 7.45 (dd, 1H, J = 9.0Hz, 2.2Hz), 7.43-7.39 (m, 2H), 7.37- 7.32 (m, 2H), 7.17 (dd, 1H, J = 9.0Hz, 2.6Hz), 5.18 (s, 2H), 1.50 (s, 9H).

(Synthesis of compound [4])
Compound [3] (122 g, 349 mmol) and 5% palladium carbon (12.2 g) were added to ethanol (976 g), and the mixture was stirred at 40 ° C. for 96 hours under a hydrogen atmosphere. Compound [4] was obtained by filtering 5% palladium carbon and concentrating the filtrate (yield: 89.3 g, yield: 99%, white crystals).
^{1 1} H-NMR (400 MHz, DMSO-d ₆ , δ (ppm)): 9.52 (s, 1H), 9.37 (s, 1H), 7.94 (s, 1H), 7.62-7 .59 (m, 1H), 7.56 (d, 1H, J = 9.2Hz), 7.39 (dd, 1H, J = 9.0Hz, 2.2Hz), 7.04-7.00 ( m, 2H), 1.50 (s, 9H).

(Synthesis of compound [5])
To dimethyl sulfoxide (500 g), 4-chloronitrobenzene (100 g, 635 mmol), ethylene glycol (551 g) and sodium hydroxide (23.1 g) were added, and the mixture was stirred at 100 ° C. for 19 hours. After cooling to room temperature, ethyl acetate (560 g) and pure water (700 g) were added to separate the liquids. After recovering the upper layer, ethyl acetate (300 g) was added to the lower layer to separate the liquids, and the upper layers were combined. Pure water (400 g) and saturated aqueous sodium chloride solution (200 g) were added to the combined upper layer, and the layers were separated again. The ethyl acetate layer was dried over sodium sulfate, filtered, and the filtrate was concentrated to obtain a crude product (a crude product was obtained. 110g). Ethyl acetate (330 g) was added to the crude product to dissolve it by heating at 60 ° C., and then hexane (550 g) was added to cool the crude product. Then, this was filtered and the filter medium was dried to obtain compound [5] (yield: 64.2 g, yield: 55%, pale yellow crystals).
^{1 1} H-NMR (400 MHz, DMSO-d ₆ , δ (ppm)): 8.21 (d, 2H, J = 9.4 Hz), 7.16 (d, 2H, J = 9.4 Hz), 4. 97 (t, 1H, J = 5.6Hz), 4.15 (t, 2H, J = 4.8Hz), 3.77-3.73 (m, 2H).

(Synthesis of compound [6])
Compound [5] (63.2 g, 345 mmol) was added to dichloromethane (1264 g), and the mixture was cooled under ice-cooling. To this was added triethylamine (52.4 g), tosyl lolide (69.0 g) and 4-dimethylaminopyridine (1.26 g), and the mixture was stirred at room temperature for 19 hours. Pure water (632 g) is added, and the solution is separated to recover the dichloromethane layer. 1N Hydrochloric acid (300 g), pure water (300 g), and saturated aqueous sodium chloride solution (300 g) are separated and washed in this order, and dried over anhydrous sodium sulfate. The mixture was filtered and the filtrate was concentrated to give compound [6] (yield: 108 g, yield: 93%, white crystals).
^{1 1} H-NMR (400 MHz, DMSO-d ₆ , δ (ppm)): 8.18 (d, 2H, J = 9.2 Hz), 7.80 (d, 2H, J = 8.6 Hz), 7. 47 (d, 2H, J = 8.6Hz), 7.05 (d, 2H, J = 9.2Hz), 4.40-4.37 (m, 2H), 4.35-4.31 (m) , 2H), 2.41 (s, 3H).

(Synthesis of compound [7])
Compound [4] (45.0 g, 174 mmol), compound [6] (61.5 g) and potassium carbonate (36.0 g) were added to dimethylformamide (360 g), and the mixture was stirred at 80 ° C. for 21 hours. After cooling to room temperature, pure water (720 g) was added to precipitate crystals. After filtration, the filter medium was slurry-washed with methanol (360 g), filtered, and the filter medium was dried to obtain compound [7] (yield: 67.2 g, yield: 91%, pale ocher crystals). ..
^{1 1} H-NMR (400 MHz, DMSO-d ₆ , δ (ppm)): 9.47 (s, 1H), 8.23 (d, 2H, J = 9.2 Hz), 8.02 (s, 1H) , 7.72-7.69 (m, 2H), 7.46 (dd, 1H, J = 8.8Hz, 2.0Hz), 7.31 (d, 1H, J = 2.4Hz), 7. 24 (d, 2H, J = 9.2Hz), 7.14 (dd, 1H, J = 9.0Hz, 2.6Hz), 4.56-4.53 (m, 2H), 4.46-4 .43 (m, 2H), 1.50 (s, 9H).

(Synthesis of compound [8])
Compound [7] (73.1 g, 172 mmol) was added to chloroform (1096 g), trifluoroacetic acid (98.1 g) was added while stirring under water cooling, and the mixture was stirred at 50 ° C. for 19 hours. After cooling to room temperature, triethylamine (87.0 g) and pure water (1096 g) were added to precipitate crystals. After filtering, the filter product was slurry-washed with methanol (365 g), filtered, and the filter product was dried to obtain a crude product (49.5 g). Dimethylformamide (124 g) was added to the crude product, and the mixture was heated and dissolved at 80 ° C., and then methanol (248 g) was added and cooled to precipitate crystals. The mixture was filtered and the filtrate was dried to obtain compound [8] (yield: 47.3 g, yield: 85%, orange crystals).
^{1 1} H-NMR (400 MHz, DMSO-d ₆ , δ (ppm)): 8.23 (d, 2H, J = 9.2 Hz), 7.51 (dd, 1H, J = 8.8 Hz, 2.4 Hz) ), 7.45 (dd, 1H, J = 8.8Hz, 2.4Hz), 7.24 (dd, 2H, J = 9.2Hz, 2.4Hz), 7.27 (s, 1H), 7 .01 (d, 1H, J = 9.2Hz), 6.91 (d, 1H, J = 8.8Hz), 6.80 (s, 1H), 5.15 (br, 2H), 4.55 -4.51 (m, 2H), 4.41-4.37 (m, 2H).

(Synthesis of compound [DA-n-2])
Compound [8] (46.4 g, 143 mmol) and 5% palladium carbon (4.6 g) were added to dimethylformamide (371 g), and the mixture was stirred at 60 ° C. for 19 hours under a hydrogen atmosphere. Since the reaction did not proceed much, the mixture was stirred at 60 ° C. for 8 hours in an autoclave under a 0.4 MPa hydrogen atmosphere. After nitrogen substitution, 5% palladium carbon was filtered and the filtrate was concentrated to bring the content to 80 g. Dimethylformamide (46 g) was added and dissolved by heating at 90 ° C., and then methanol (210 g) was added and cooled to precipitate crystals. Then, this was filtered and the filtrate was dried to obtain compound [DA-n-2] (yield: 33.4 g, yield: 79%, pale purple crystals).
¹ H-NMR (400 MHz, DMSO-d ₆ , δ (ppm)): 7.50 (d, 1H, J = 8.8 Hz), 7.44 (d, 1H, J = 8.8 Hz), 7. 13 (d, 1H, J = 2.8Hz), 7.00 (dd, 1H, J = 8.8Hz, 2.8Hz), 6.90 (dd, 1H, J = 8.8Hz, 2.4Hz) , 6.79 (d, 1H, J = 2.4Hz), 6.71 (d, 2H, J = 8.8Hz), 6.52 (d, 2H, J = 8.8Hz), 5.13 ( br, 2H), 4.63 (br, 2H), 4.28-4.25 (m, 2H), 4.20-4.17 (m, 2H).

<Synthesis of compound [DA-n-3]>
Compound [DA-n-3] was synthesized according to the following scheme.

(Synthesis of compound [9])
6-Bromo-2-naphthaleneamine (30.0 g, 135 mmol), tetrahydrofuran (450 g), (4-nitrophenyl) boronic acid (27.2 g, 163 mmol), methanol (300 g), carbonate in a four-necked flask. Cesium (132 g, 405 mmol) and water (150 g) were charged and replaced with nitrogen. Tetrakis (triphenylphosphine) palladium (0) (3.12 g, 2.70 mmol) was added thereto, the mixture was replaced with nitrogen, and the mixture was stirred overnight at 55 ° C. After completion of the reaction, the reaction solution was added to water (750 g) to precipitate crystals, and the crystals were collected by filtration. Isopropyl alcohol (216 g) was added to the obtained crystals, and the mixture was heated and stirred at 65 ° C., and toluene (300 g) was added while cooling to room temperature for crystallization. This was filtered, the cake was washed with toluene and hexane, and the crystals were dried to obtain compound [9] (yield: 28.0 g, 106 mmol, yield 78%).
^{1 1} H-NMR (500 MHz, DMSO-d ₆ , δ (ppm)): 8.30 (d, J = 8.5 Hz, 2H), 8.13 (s, 1H), 8.03 (d, J = 8.6Hz, 2H), 7.72 (d, J = 8.8Hz, 2H), 7.63 (d, J = 8.7Hz, 1H), 7.00 (d, J = 8.5Hz, 1H) ), 6.85 (s, 1H), 5.63 (s, 2H).

(Synthesis of compound [DA-n-3])
To compound [9] (28.0 g, 106 mmol), N, N-dimethylformamide (224 g) was added and replaced with nitrogen, then 5% palladium carbon (hydrous product, 2.24 g) was added and replaced with nitrogen, and hydrogen was substituted. A tedler bag was attached and the mixture was stirred at room temperature overnight. After completion of the reaction, palladium carbon was removed by passing through a membrane filter, the filtrate was added to water (248 g) to precipitate crystals, and the crystals were filtered to recover the crystals (wet). Isopropyl alcohol (50 g) was added to the obtained crystals, and the mixture was heated and stirred at 55 ° C., and toluene (74 g) was added while cooling to room temperature for crystallization. The crystals were collected by filtration (crystal A). The filtrate was concentrated, crystallized again with isopropyl alcohol (55 ° C.)-toluene (room temperature), filtered, and the crystals were recovered (crystal B). The obtained crystals A and B were dried and compounded [DA-n-. 3] was obtained. (Yield: 17.6 g, 75.1 mmol, yield 71%).
^{1 1} H-NMR (500 MHz, DMSO-d ₆ , δ (ppm)): 7.76 (s, 1H), 7.60 (d, J = 8.7 Hz, 1H), 7.53-7.49 ( m, 2H), 7.41 (d, J = 8.2Hz, 2H), 6.92 (d, J = 8.7Hz, 1H), 6.80 (s, 1H), 6.66 (d, J = 8.2Hz, 2H), 5.25 (s, 4H).

<Synthesis example of compound [DA-n-9]>
Compound [DA-n-9] was synthesized according to the following scheme.

(Synthesis of compound [4])
Compound [4], which is a synthetic intermediate in [DA-n-2], was used.
(Synthesis of compound [10])
Ethylene glycol ditosylate (60.7 g, 164 mmol), compound [4] (89.3 g) and potassium carbonate (56.7 g) were added to dimethylformamide (607 g), and the mixture was stirred at 80 ° C. for 22 hours. After cooling to room temperature, pure water (1200 g) was added to precipitate crystals. Then, it was filtered, and the filter product was slurry-washed with methanol (450 g), filtered, and the filter product was dried to obtain a crude product (83.9 g). Dimethylformamide (839 g) was added to the crude product, and the mixture was heated and dissolved at 90 ° C., and then methanol (839 g) was added and cooled to precipitate crystals. Then, the mixture was filtered and the filtrate was dried to obtain compound [10] (yield: 71.2 g, yield: 80%, orange crystals).
^{1 1} H-NMR (400 MHz, DMSO-d ₆ , δ (ppm)): 9.43 (s, 2H), 7.99 (br, 2H), 7.67 (d, 4H, J = 8.8 Hz) , 7.43 (dd, 2H, J = 8.8Hz, 2.4Hz), 7.28 (d, 2H, J = 2.4Hz), 7.12 (dd, 2H, J = 8.8Hz, 2) .4Hz), 4.42 (s, 4H), 1.47 (s, 18H).

(Synthesis of compound [DA-n-9])
Compound [10] (71.2 g, 129 mmol) was added to chloroform (1143 g), and the mixture was cooled under water cooling. Trifluoroacetic acid (160 g) was added thereto, and the mixture was stirred at 50 ° C. for 24 hours. After cooling to room temperature, triethylamine (142 g) and pure water (1143 g) were added to precipitate crystals. Then, it was filtered, and the filter product was slurry-washed with methanol (400 g), filtered, and the filter product was dried to obtain a crude product (37.5 g). Dimethylformamide (225 g) was added to the crude product, and the mixture was heated and dissolved at 90 ° C., and then methanol (225 g) was added and cooled to precipitate crystals. The compound DA-n-9 was obtained by filtration and drying the filter (yield: 33.5 g, yield: 75%, pale reddish purple crystals).
^{1 1} H-NMR (400 MHz, DMSO-d ₆ , δ (ppm)): 7.51 (d, 2H, J = 8.8 Hz), 7.45 (d, 2H, J = 8.8 Hz), 7. 17 (d, 2H, J = 2.4Hz), 7.02 (dd, 2H, J = 8.8Hz, 2.4Hz), 6.91 (dd, 2H, J = 8.8Hz, 2.4Hz) , 6.80 (d, 2H, J = 2.4Hz), 5.14 (br, 4H), 4.37 (s, 4H).

<Synthesis example of compound [DA-n-10]>
Compound [DA-n-10] was synthesized according to the following scheme.

(Synthesis of compound [11])
N, N-dimethylformamide (216 g) and potassium carbonate (33 g, 239 mmol) were added to tert-butyl (5-hydroxy-1-naphthalenyl) carbamate (27.0 g, 104 mmol), and the mixture was stirred at 80 ° C. Next, a solution of 1,2-bis (4-methylbenzenesulfonate) -1,2-ethanediol (18.0 g, 496 mmol) in N, N-dimethylformamide (162 g) was added dropwise with a dropping funnel at 80 ° C. It was heated and stirred overnight. After completion of the reaction, the reaction solution was poured into water (2268 g) to precipitate crystals. The mixture was filtered using a Büchner funnel to obtain sticky black-purple crystals (93 g). N, N-dimethylformamide was added to the obtained crude product, dissolved by heating at 80 ° C., crystallized with methanol while cooling to room temperature, filtered and dried to obtain compound [11] (yield: 28). 0.0 g, 51.4 mmol, yield 67%).
^{1 1} H-NMR (500 MHz, DMSO-d ₆ , δ (ppm)): 9.14 (s, 2H), 7.98 (d, J = 10.0 Hz, 2H), 7.64 (d, J = 10.0Hz, 2H), 7.55 (d, J = 10.0Hz, 2H), 7.46 (t, J = 7.5Hz, 2H), 7.39 (t, J = 7.5Hz, 2H) ), 7.13 (d, J = 10.0Hz, 2H), 4.65 (s, 4H), 1.49 (s, 18H).

(Synthesis of compound [DA-n-10])
Chloroform (374 g) and potassium carbonate (33 g, 239 mmol) were added to compound [11] (28.0 g, 51.4 mmol), and the mixture was stirred at 80 ° C. Next, trifluoroacetic acid (31.0 g, 313 mmol) was slowly added dropwise with a dropping funnel, and the mixture was heated and stirred at 50 ° C. for 6 hours, and gray crystals were precipitated in the reaction system. After cooling to 25 ° C., the reaction solution was poured into water (374 g) and filtered. To the obtained crystals, triethylamine and water were added and stirred to liberate the diamine from the trifluoroacetic acid salt, filtered again, washed with methanol and then hexane, and dried to obtain the compound [DA-n-10]. Obtained (yield: 9.30 g, 27.0 mmol, yield 86%).
^{1 1} H-NMR (500 MHz, DMSO-d ₆ , δ (ppm)): 7.65 (d, J = 7.5 Hz, 2H), 7.41 (d, J = 8.0 Hz, 2H), 7. 29 (t, J = 8.0Hz, 2H), 7.12 (t, J = 8.0Hz, 2H), 7.00 (t, J = 7.5Hz, 2H), 6.67 (d, J) = 7.5Hz, 2H), 5.62 (s, 4H), 4.56 (s, 4H).

<Synthesis of DA-v-7>
Compound [DA-v-7] was synthesized according to the following scheme. "MeO" represents a methoxy group.

(Synthesis of Compound 3 (3a, 3b mixture))
Magnesium (15.39 g, 63.3 mmol, 1.5 eq.) Is added to a four-necked flask, vacuum dried with a vacuum pump for 1 hour, then THF (100 g) is added with a syringe, and the mixture is stirred at room temperature. did. Next, a solution of compound 1 (100 g, 42.2 mmol) in THF (300 g) was added slowly and dropwise at a rate of gently refluxing. Then, the reaction solution was cooled to 0 ° C., and a solution of Compound 2 (105.60 g, 42.2 mmol, 1.0 eq.) In THF (200 g) was added dropwise. After the dropping was completed, the temperature of the reaction solution was returned to room temperature, and the mixture was stirred at room temperature for 3 hours. Then, toluene (1 L) was added to dilute the reaction solution, the reaction solution was cooled to 0 ° C. again, and a 10% acetic acid solution (500 g) was gradually added dropwise.
Next, the aqueous layer is removed by a liquid separation operation, the organic layer is washed with saturated brine (1 L), saturated aqueous sodium hydrogen carbonate solution (1 L), and saturated brine (1 L), and the organic layer is washed with anhydrous magnesium sulfate. Was dried. Then, it was filtered and distilled by an evaporator to obtain 172 g of a crude crystal of compound 3. The obtained crude crystals were used as they were in the next reaction.

(Synthesis of Compound 4)
A mixture of crude crystals of compound 3 (172 g, 422 mmol) and p-toluenesulfonic acid monohydrate (4.82 g, and 25.3 mmol, 0.06 eq.) In dehydrated toluene (MS4A dehydrated product, 2 L) under reflux. , The reaction was carried out for 2 hours while draining water. After completion of the reaction, about half of the amount of toluene used was distilled off with an evaporator, and then the solution was stirred at room temperature to precipitate a solid. The obtained solid was filtered to obtain crystals of compound 4 (gain: 150 g, yield 91%).

(Synthesis of Compound 5 (mixture of 5a and 5b))
A mixture of compound 4 (108 g, 276 mmol), 5% palladium carbon (hydrous product, 11 g, 10 wt%), ethyl acetate (1 L) and ethanol (1 L) was stirred in the presence of hydrogen at room temperature. After completion of the reaction, toluene (2 L) was added to dissolve the crystals, the reaction mixture was filtered through Celite, and Celite was washed with 1 L of toluene. When the filtrate was concentrated under reduced pressure, the target compound 5 was obtained (gain: 103.3 g, yield 95%).

(Synthesis of Compound 6)
_{BBr 3} (1.0 M-CH ₂ Cl ₂ , 243 mL, 1.01 mol) was added dropwise to a solution of compound 5 (95.4 g, 243 mmol) in methylene chloride (800 mL) at 0 ° C. under nitrogen substitution. After the dropping, the mixture was stirred at 0 ° C. for 2 hours. After completion of the reaction, the reaction solution was added little by little to the distilled water. The extract was extracted with ethyl acetate (1 L), and the extract was washed twice with 500 mL of distilled water. The organic layer was dried over magnesium sulfate, and the solvent was evaporated under reduced pressure. The obtained crude product was recrystallized from ethanol, filtered, and washed with ethanol to obtain the target compound 6 (18.6 g obtained, 21% yield).

(Synthesis of Compound 8)
Compound 7 (5.35 g, 26.4 mmol) in a mixture of compound 6 (10.0 g, 26.4 mmol), potassium carbonate (11.0 g, 79.2 mmol, 3 eq.), And toluene (50 g) under reflux. ) Intoluene (20 g) solution was added dropwise. After the dropping, the mixture was stirred at reflux overnight. After completion of the reaction, the reaction solution was cooled to about 60 ° C., ethyl acetate (500 g) was added, and the mixture was washed 3 times with distilled water. The organic layer was dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The obtained crude product was recrystallized from an acetonitrile / ethanol (2: 1) solution, filtered, and then the filtered crystals were washed with ethanol to obtain crude crystals of Compound 8. The crude crystals were purified by column chromatography (SiO ₂ , CHCl ₃ ) to obtain crystals of compound 8 (yield 7.1 g, yield 49%).

(Synthesis of DA-v-7)
A mixture of Compound 8 (12.2 g, 22.4 mmol), 5% palladium carbon (hydrous product, 1.22 g, 10 wt%) and 1,4-dioxane (120 g) was stirred at 60 ° C. for 4 hours in the presence of hydrogen. did. After completion of the reaction, nitrogen substitution was carried out, and then the mixture was filtered through Celite at 60 ° C. The filtrate was evaporated under reduced pressure to give a crude product. The crude product was recrystallized from 2-propanol / ethyl acetate (2: 1) to obtain the desired product, DA-v-7 (gain: 8.0 g, yield: 74%).
^{1 1} H-NMR (500 MHz, CDCl ₃ , δ (ppm)): 7.725 (1H, d), 7.577 (2H, m), 7.272 (2H, m), 7.102 (1H, s) ), 6.791 (1H, d), 6.207 (1H, d), 6.117 (1H, dd), 3.621 (4H, road), 2.553 (1H, m), 2.067. -0.863 (31H, m).

[Synthesis of polyamic acid]
<Synthesis example 1>
1.66 g (7.00 mmol) of DA-4, 2.89 g (8.75 mmol) of DA-5, 5.30 g (7.00 mmol) of DA-v-6 in a 100 mL four-necked flask with a stirrer. , DA-13 was weighed in 2.43 g (12.3 mmol), 49.1 g of NMP was added, and the mixture was stirred and dissolved. While stirring this diamine solution, 7.53 g (33.6 mmol) of DC-3 was added, 30.1 g of NMP was further added, and the mixture was stirred at 60 ° C. for 15 hours to obtain a polyamic acid (AR1, viscosity: 649 mPa · s). , A solution having a number average molecular weight of 14,231) was obtained.

<Synthesis Examples 2 to 13>
The polyamic acid solution (AR2) shown in Table 1 below was carried out in the same manner as in Synthesis Example 1 except that the diamine component and the acid dianhydride component were changed to those shown in Table 1 below. -(A-R9) and (A-B1)-(A-B4) were obtained. The viscosity and molecular weight of the obtained polyamic acid are also shown in Table 1 below.

[Preparation of liquid crystal alignment agent]
<Example 1>
NMP (6.0 g) and BCS (8.0 g) were added to the solution (6.0 g) of the polyamic acid (AR1) obtained above, and the mixture was stirred at room temperature for 10 hours to obtain the polyamic acid (AR1). A liquid crystal aligning agent (R1) containing 6% by mass, 54% by mass of NMP, and 40% by mass of BCS was obtained.

<Synthesis Examples 2 to 13>
As shown in Table 2 below, instead of the polyamic acid (A-R1), except that the polyamic acids (A-R2) to (A-R9) and (A-B1) to (A-B4) were used. By carrying out in the same manner as in Example 1, the liquid crystal alignment agents (R2) to (R9) and (B1) to (B4) of Examples 2 to 13 shown in Table 2 were obtained, respectively.
In Examples 1 to 13 of Table 2, Examples 1 to 3 and 6 to 9 are comparative examples, and Examples 4, 5, 10 to 13 are examples of the present invention.

The solid content ratio in Table 2 above represents the content ratio of the polymer solid content with respect to 100 parts by mass of the liquid crystal aligning agent, and the solvent composition ratio represents the content ratio (parts by mass) in each organic solvent.

<Examples 14 to 21>
The liquid crystal alignment agent (R1) obtained in Example 1 and the liquid crystal alignment agent (R4) obtained in Example 4 are mixed so that their mass ratios are 3: 7, and the mixture is stirred at room temperature for 3 hours. , Example 14 liquid crystal alignment agent (B5) was prepared.
Further, in Examples 15 to 21, by carrying out in the same manner as in Example 14 except that the combination of the liquid crystal alignment agents used was changed to those shown in Table 3 below, Examples 15 to 21 shown in Table 3 below, respectively. Liquid crystal alignment agents (B6 to B8, R10 to R13) were prepared.

<Examples 22 to 35>
A liquid crystal alignment film and a liquid crystal cell were prepared as described below, and the characteristics of each of the prepared liquid crystal cells were evaluated. The results are shown in Table 4 below. In the following examples, Examples 22 to 25 and 28 to 31 are examples of the present invention, and Examples 26, 27 and 32 to 35 are comparative examples.
[Preparation of liquid crystal alignment film]
Using the liquid crystal alignment agents prepared in Examples 1 to 21, a liquid crystal alignment film was prepared as follows. Each liquid crystal alignment agent is spin-coated on a quartz substrate or a silicon wafer, dried on a hot plate at 70 ° C. for 90 seconds, and then baked in a hot air circulation oven (MB1-1G3030X, manufactured by Denko) at 230 ° C. for 20 minutes. , A liquid crystal alignment film having a film thickness of 100 nm was formed.

[Measurement of refractive index of liquid crystal alignment film]
Using a spectroscopic ellipsometer (M-2000, manufactured by JA Woollam), fitting by a Cauchy model was performed, and the refractive index at a wavelength of 250 to 800 nm was measured. The results are shown in Table 4. Table 4 shows the refractive index at a wavelength of 550 nm. When the refractive index was larger than 1.62, it was regarded as "good", and when it was 1.62 or less, it was regarded as "poor".

[Measurement of transmittance of liquid crystal alignment film]
A measurement cell was prepared using two quartz substrates. A liquid crystal alignment film was formed on one of the two sheets, and a quartz substrate on which the liquid crystal alignment film was not formed was attached with the side surface on which the liquid crystal alignment film was formed inside. In the meantime, a refracting liquid (contact liquid, manufactured by Shimadzu Device Manufacturing Co., Ltd.) was inserted using a dropper to prepare a measurement cell. The refracting liquid was used from 11 types in 0.01 increments of 1.60 to 1.70 according to the respective refractive index.
Using an ultraviolet-visible spectrophotometer (UV-2600, manufactured by Shimadzu Corporation), the transmittance of the measurement cell prepared above at a wavelength of 380 to 800 nm was measured. The results are shown in Table 4. Table 4 shows the average value of the transmittance at a wavelength of 380 to 800 nm.
When the transmittance was greater than 99.0%, it was evaluated as "good", and when it was 99.0% or less, it was evaluated as "poor".

"Preparation of liquid crystal alignment film and liquid crystal cell"
Using the liquid crystal alignment agent prepared in each of the above examples, a liquid crystal cell was prepared as follows.
Each liquid crystal alignment agent was spin-coated on the ITO surface of an ITO electrode substrate having an ITO electrode pattern having a pixel size of 100 μm × 300 μm and a line / space of 5 μm, and dried on a hot plate at 70 ° C. for 90 seconds. , 230 ° C., hot air circulation type oven (MB1-1G3030X, manufactured by Denko) for 30 minutes to form a liquid crystal alignment film having a film thickness of 100 nm.
Further, the liquid crystal aligning agent is spin-coated on the ITO surface on which the electrode pattern is not formed, dried on a hot plate at 70 ° C. for 90 seconds, and then placed in a hot air circulation oven (MB1-1G3030X, manufactured by Denko) at 230 ° C. It was baked for 20 minutes to form a liquid crystal alignment film having a film thickness of 100 nm.

For the above two substrates, a 4 μm bead spacer was sprayed on the liquid crystal alignment film of one of the substrates, and then a sealant (solvent type thermosetting type epoxy resin) was printed on the bead spacers. Next, the surface of the other substrate on which the liquid crystal alignment film was formed was turned inside, and after bonding with the previous substrate, the sealant was cured to prepare an empty cell. A liquid crystal MLC-3023 (trade name manufactured by Merck & Co., Inc.) containing a polymerizable compound was injected into the empty cell by a reduced pressure injection method to prepare a liquid crystal cell.

Then, with a DC voltage of 15 V applied to the liquid crystal cell, UV was irradiated at ^{10 J / cm 2} from the outside of the liquid crystal cell through a filter that cuts a wavelength of 325 nm or less. The illuminance of UV was measured using an ultraviolet irradiation degree meter (UV-MO3A manufactured by ORC). After that, for the purpose of inactivating the unreacted polymerizable compound remaining in the liquid crystal cell, UV (UV lamp: UV lamp:) was used using a UV-FL irradiation device (manufactured by Toshiba Litec) in a state where no voltage was applied. FLR40SUV32 / A-1) was irradiated for 30 minutes.

"Evaluation of liquid crystal cell"
The method for evaluating the characteristics of each liquid crystal cell produced as described above is as follows.
(Evaluation of vertical orientation)
The liquid crystal cell was sandwiched between cross Nicol polarizing plates, and the liquid crystal cell was rotated in a state where the backlight was irradiated from the rear part, and it was visually observed whether the liquid crystal was vertically oriented by the change of brightness. The evaluation criteria are as follows.
◯: The liquid crystal is vertically oriented. X: The liquid crystal is not vertically oriented.

The entire contents of the specification, claims and abstract of Japanese Patent Application No. 2019-173271 filed on September 24, 2019 are cited here and incorporated as disclosure of the specification of the present invention. Is.

Claims

At least one polymer (P) selected from the group consisting of a polyimide precursor obtained by using a diamine component containing a diamine (0) represented by the following formula (0) and polyimide which is an imide of the polyimide precursor. ), A liquid crystal aligning agent for vertical alignment.

(In the formula (0), A and A'independently represent a monocyclic group, a condensed ring group, or a group in which two monocyclic groups are bonded, and at least one of A and A'is Representing a fused ring group. L represents a single bond or -X 1- Q-X 2- group. X 1 and X 2 independently represent a single bond, an oxygen atom or a sulfur atom. Q Represents an alkylene group having 1 or 2 carbon atoms.)
Claim 1 in which the fused ring group is a divalent group obtained by removing two hydrogen atoms from a fused ring which is any one of naphthalene, anthracene, pyrene, indole, carbazole, coumarin, benzo-pyrone, quinoline, or isoquinoline. The liquid crystal alignment agent according to.
The liquid crystal alignment agent according to claim 1 or 2, wherein the diamine (0) is a diamine represented by the following formula (1).

(In the formula (1), A represents a monocyclic group, a condensed ring group, or a group in which two monocyclic groups are bonded, and L represents a single bond or -X 1- Q-X 2- . X 1 and X 2 independently represent a single bond, an oxygen atom or a sulfur atom, and Q represents an alkylene group having 1 or 2 carbon atoms.
The liquid crystal alignment agent according to claim 3, wherein in the formula (1), A is a phenylene group, a pyridinyl group, a naphthylene group, an anthracenyl group, a quinolinyl group, a biphenyl structure, or a bipyridinyl group.
The diamines represented by the formula (1) are the following formulas (d-1) to (d-7), (d-13) to (d-14), (d-17) to (d-18) and The liquid crystal alignment agent according to claim 3 or 4, which is any diamine selected from the group consisting of (d-21).
The diamine (0) is selected from the group consisting of the following formulas (d-8) to (d-12), (d-15), (d-16), (d-19) and (d-20). The liquid crystal alignment agent according to claim 1, which is any diamine.
Claim 1 obtained by using a diamine component further containing a diamine (s) in which the polymer (P) has at least one selected from the group consisting of the structures represented by the following formulas (S1) to (S3). The liquid crystal alignment agent according to any one of 6 to 6.

(X 1 and X 2 are independent, single bond,-(CH 2 ) a- (a is an integer of 1 to 15), -CONH-, -NHCO-, -CON (CH 3 )- , -NH-, -O-, -COO-, -OCO- or-((CH 2 ) a1- A 1 ) m1- (a1 is an integer from 1 to 15, and A 1 is an oxygen atom or -COO- , And m 1 is an integer of 1 to 2. When m 1 is 2, a plurality of a 1 and A 1 have the above definitions independently of each other). G 1 and G 2 are independent of each other. Then, it represents a divalent cyclic group selected from a divalent aromatic group having 6 to 12 carbon atoms and a divalent alicyclic group having 3 to 8 carbon atoms. Any hydrogen atom on the cyclic group represents. , An alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxy group having 1 to 3 carbon atoms, or a fluorine atom may be substituted. .M and n are independently integers of 0 to 3, and the sum of m and n is 1 to 6. R 1 is an alkyl group having 1 to 20 carbon atoms and an alkoxy having 1 to 20 carbon atoms. Any hydrogen atom representing a group or an alkoxyalkyl group having 2 to 20 carbon atoms and forming R 1 may be substituted with a fluorine atom.)

(X 3 represents a single bond, -CONH-, -NHCO-, -CON (CH 3 )-, -NH-, -O-, -CH 2 O-, -COO- or -OCO- R 2 Represents an alkyl group having 1 to 20 carbon atoms or an alkoxyalkyl group having 2 to 20 carbon atoms, and any hydrogen atom forming R 2 may be substituted with a fluorine atom.)

(X 4 represents -CONH-, -NHCO-, -O-, -CH 2 O-, -OCH 2- , -COO- or -OCO-. R 3 represents a structure having a steroid skeleton.)
The liquid crystal alignment agent according to claim 7, wherein the diamine (s) is a diamine represented by the following formula (d1) or formula (d2).

(X is a single bond, -O-, -C (CH 3 ) 2- , -NH-, -CO-,-(CH 2 ) m- , -SO 2- , -O- (CH 2 ) m- O -, - O-C ( CH 3) 2 -, - CO- (CH 2) m -, - NH- (CH 2) m -, - SO 2 - (CH 2) m -, - CONH- (CH 2) m -, - CONH- ( CH 2) m -NHCO -, - COO- (CH 2) m -OCO -, - COO -, - CONH -, - NH- (CH 2) m -NH- or - It represents SO 2- (CH 2 ) m- SO 2-. M is an integer of 1 to 8. Y represents any structure of the above formulas (S1) to (S3), and in the formula (d2). The two Ys may be the same or different.)
The liquid crystal alignment agent according to claim 8, wherein the diamine represented by the formula (d1) is any diamine selected from the group consisting of the following formulas (d1-1) to (d1-18).

(N is an integer from 1 to 20.)
The liquid crystal alignment agent according to claim 8, wherein the diamine represented by the formula (d2) is any diamine selected from the group consisting of the following formulas (d2-1) to (d2-6).

(X p1 to X p8 are independently each of-(CH 2 ) a- (a is an integer of 1 to 15), -CONH-, -NHCO-, -CON (CH 3 )-,-. NH -, - O -, - CH 2 O -, - CH 2 OCO -, - COO-, or -OCO- .X s1 ~ X s4 representative of a is independently, -O -, - CH 2 O- , -OCH 2- , -COO- or -OCO-. X a to X f are -O-, -NH-, -O- (CH 2 ) m- O-, -C (CH 3 ) 2 -, -CO-, -COO-, -CONH-,-(CH 2 ) m- , -SO 2- , -OC (CH 3 ) 2- , -CO- (CH 2 ) m- , -NH - (CH 2) m -, - NH- (CH 2) m -NH -, - SO 2 - (CH 2) m -, - SO 2 - (CH 2) m -SO 2 -, - CONH- (CH 2 ) Represents m- , -CONH- (CH 2 ) m- NHCO-, or -COO- (CH 2 ) m- OCO-. R 1a to R 1h are independently alkyl having 1 to 20 carbon atoms. Represents a group, an alkoxy group having 1 to 20 carbon atoms, or an alkoxyalkyl group having 2 to 20 carbon atoms. M is an integer of 1 to 8).
Any of claims 1 to 10 obtained by the polymerization reaction of the polymer (P) with the diamine component and a tetracarboxylic acid component containing a tetracarboxylic dianhydride represented by the following formula (T). The liquid crystal aligning agent according to item 1.

(X represents a structure selected from the following formulas (x-1) to (x-13).)

(R 1 to R 4 independently represent a hydrogen atom, a methyl group, an ethyl group, a propyl group, a chlorine atom or a phenyl group. R 5 and R 6 independently represent a hydrogen atom or a methyl group, respectively. J and k are independently integers of 0 or 1 , respectively. A 1 and A 2 independently represent a single bond, ether, carbonyl, ester, phenylene, sulfonyl or amide group. , Two A 2s may be the same or different. * 1 is a bond that binds to one acid anhydride group, and * 2 is a bond that binds to the other acid anhydride group. It is a hand.)
The liquid crystal alignment agent according to claim 11, wherein X in the formula (T) is any one of the formulas (x-1) to (x-7) and (x-11) to (x-13).
The liquid crystal alignment agent according to any one of claims 1 to 12, wherein the diamine (0) is contained in an amount of 1 to 100 mol% in the total diamine component.
The liquid crystal alignment agent according to any one of claims 7 to 13, wherein the diamine (s) is contained in an amount of 1 to 99 mol% in the total diamine component.
A liquid crystal alignment film for vertical alignment formed by using the liquid crystal alignment agent according to any one of claims 1 to 14.
A liquid crystal display element including the liquid crystal alignment film according to claim 15.
The liquid crystal aligning agent according to any one of claims 1 to 14 is applied onto a pair of substrates having a conductive film to form a coating film so that the coating films face each other via a layer of liquid crystal molecules. A method for manufacturing a liquid crystal display element, which forms a liquid crystal cell by arranging the liquid crystal cells facing each other and irradiates the liquid crystal cell with light in a state where a voltage is applied between the conductive films of the pair of substrates.
A diamine represented by the following formula (2-1) or (2-2).
A polymer obtained from the diamine component containing the diamine according to claim 18.
A polyimide precursor or an imidized polyimide obtained by a polycondensation reaction between a diamine-containing diamine component according to claim 18 and a tetracarboxylic acid component.