TW201947029A - Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element - Google Patents

Abstract

The present invention includes a polymer obtained from diamine components including at least one first diamine represented by general formula [I] and at least one second diamine having a side-chain structure selected from groups represented by general formulas [S1] to [S3], and an organic solvent. (In formula [I], Z1 represents an S atom or an O atom, and * represents a site for bonding to other groups; any of the hydrogen atoms in the benzene ring may be substituted with a monovalent organic group.) (In formula [S1], X1 and X2 each independently represent a single bond, -(CH2)a- (where a is an integer of 1-15), -CONH-, -NHCO-, -COs-NH-, -O-, -COO-, -OCO-, or -((CH2)a1-A1)m1-. Therein, each of the plurality of a1 independently represents an integer of 1-15, each of the plurality of A1 independently represents an oxygen atom -COO-, and m1 is 1-2. G1 and G2 each independently represent a divalent cyclic group selected from C6-12 divalent aromatic groups and C3-8 divalent alicyclic groups. Any of the hydrogen atoms in the cyclic group may be substituted with at least one selected from the group consisting of C1-3 alkyl groups, C1-3 alkoxyl groups, C1-3 fluorine-containing alkyl groups, C1-3 fluorine-containing alkoxyl groups, and fluorine atoms. m and n each independently represent an integer of 0-3, where the sum of m and n is 1-4. R1 represents a C1-20 alkyl, a C1-20 alkoxy, or a C2-20 alkoxyalkyl. Any of the hydrogens that form the R1 may be substituted with fluorine.) (In formula [S2], X3 represents a single bond, -CONH-, -NHCO-, -CON(CH3)-, -NH-, -O-, -CH2O-, -COO-, or -OCO. R2 represents a C1-20 alkyl or a C2-20 alkoxyalkyl; any of the hydrogens that form R2 may be substituted with fluorine.) (In formula [S3], X4 represents -CONH-, -NHCO-, -O-, -COO-, or -OCO-; R3 represents a structure having a steroid backbone.).

Description

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

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

Liquid crystal display elements are currently widely used as thinner. Lightweight display. It is known that the display characteristics of a liquid crystal display element are greatly affected by the alignment of the liquid crystal, the size of the pretilt angle of the liquid crystal, the stability of the pretilt angle, and the electrical characteristics. In order to improve the display characteristics of such a liquid crystal display element, the phase characteristics Compared with the liquid crystal material used, it is more important that the liquid crystal alignment film is in direct contact with the liquid crystal and has a liquid crystal alignment film that determines the alignment state.

At present, liquid crystal alignment films are mainly used as a liquid crystal alignment agent for a polyamic acid or polyimide resin solution. These are coated on a substrate and then fired. The coating film surface is formed by applying pressure (that is, performing a so-called rubbing treatment).

A method for obtaining a liquid crystal alignment film from polyimide or polyamic acid as a precursor thereof, a resin solution can be produced by a simple process called coating and firing to have excellent heat resistance and solvent resistance. The coating film can easily align the liquid crystal by rubbing. Therefore, it has been widely used in industry.

In addition, in order to improve the display characteristics of liquid crystal display elements, by selecting various structures of fluoric acid or polyimide, or resins with different blending characteristics, etc., to further improve the alignment of the liquid crystal, improve the control of the pretilt angle, and Various techniques have been proposed for its stability, improving the voltage retention rate, or making it difficult to accumulate the accumulated charge for the DC voltage, and improving the ease of release of the accumulated charge. For example, Patent Document 1 proposes a polyfluorene resin having a specific repeating unit for obtaining a high voltage holding ratio. In addition, Patent Document 2 proposes to use a soluble polyfluorene imide having a nitrogen atom in addition to the fluorenimine group to reduce the time until the afterimage disappears.

However, with the progress of high performance of liquid crystal display elements, power saving of display devices, and improvement of durability in various environments, the voltage retention rate in high temperature environments is low, resulting in contrast. Problems such as reduction, or problems such as burn-in caused by charge accumulation during continuous driving for a long period of time will become significant. It is difficult to solve both problems at the same time using only the technology proposed in the past. .
[Prior technical literature]
[Patent Literature]

[Patent Document 1] Japanese Unexamined Patent Publication No. 2-287324
[Patent Document 2] Japanese Patent Application Laid-Open No. 10-104633

[Problems to be Solved by the Invention]

In view of such circumstances, the present invention aims to provide a liquid crystal alignment agent, a liquid crystal alignment film, and a liquid crystal display element for the relaxation of accumulated charge for fast and reliable (especially the reliability after aging at high temperature and humidity). .

[Means for solving problems]

As a result of intensive research, the present inventors have found that by introducing a specific diamine having a furan ring and a thiophene ring together with a diamine having a specific side chain structure as a diamine component, it is possible to ensure good afterimage characteristics and high Reliability, thus completing the present invention.

The liquid crystal alignment agent of the present invention which achieves the above object is characterized by including a polymer obtained with a diamine component and an organic solvent, and the diamine component contains at least 1 of the first diamine represented by the following formula [I]. And at least one kind of second diamine having a side chain structure selected from the group represented by the following formulae [S1] to [S3].

(In the formula [I], Z ¹ represents an S atom or an O atom, * represents a site bonded to another group, and an arbitrary hydrogen atom of a benzene ring may be substituted with a monovalent organic group).

(In the formula [S1], X ¹ and X ² each independently represent a single bond,-(CH ₂ ) _a- (a is an integer of 1 to 15), -CONH-, -NHCO-, -COs-NH-,- O-, -COO-, -OCO-, or-((CH ₂ ) _a1 -A ₁ ) _m1- , where a plurality of a1 are each independently an integer of 1 to 15, and a plurality of A ₁ each independently represent an oxygen atom or- COO-, m ₁ is 1 to 2, G ¹ and G ² each independently represent a divalent cyclic group selected from a divalent aromatic group having 6 to 12 carbon atoms or a divalent alicyclic group having 3 to 8 carbon atoms An arbitrary hydrogen atom on the aforementioned cyclic group may be selected from 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, and 1 to 3 carbon atoms. Substituted by at least one of the group consisting of a fluorine-containing alkoxy group or a fluorine atom, m and n are each independently an integer of 0 to 3 and the total of m and n is 1 to 4, R ¹ represents a carbon number of 1 An alkyl group of ~ 20, an alkoxy group of 1 to 20 carbons, or an alkoxyalkyl group of 2 to 20 carbons, any hydrogen forming R ¹ may be substituted by fluorine).

(In the formula [S2], 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 alkoxy group having 2 to 20 carbon atoms Alkyl, any hydrogen that forms R ² may be replaced by fluorine).

(In the formula [S3], X ⁴ represents -CONH-, -NHCO-, -O-, -COO-, or -OCO-, and R ³ represents a structure having a steroid skeleton).

The polymer is preferably at least one polymer selected from the group consisting of a polyimide precursor and a polyimide which is a polyimide, and the polyimide precursor has a A polycondensate obtained by using a diamine having a structure represented by the aforementioned formula [1] and a tetracarboxylic dianhydride.

The first diamine has a specific characteristic represented by the following formula [II].

(In the formula [II], the definition of Z ¹ is the same as the above formula [I], P ² independently represents a single bond or the structure of the following formula [II-1], n represents an integer of 1 to 3, and Arbitrary hydrogen atoms may be substituted by a monovalent organic group).

(In formula [II-1], P ³ represents a single bond, -O-, -COO-, -OCO-,-(CH ₂ ) _l- , -O (CH ₂ ) _m O-, -CONH- And -NHCO- divalent organic groups (l and m represent integers from 1 to 5), * ₁ represents a site bonded to a benzene ring in formula [II], and * ₂ represents an amine with formula [II] Base bond).

The side chain structure represented by the aforementioned formula [S1] is preferably at least one selected from the group consisting of the following formulas [S1-x1] to [S1-x7].

(In the formulas [S1-x1] to [S1-x7], R ¹ represents an alkyl group having 1 to 20 carbon atoms, and X ^p represents
-(CH ₂ ) _a- (a is an integer from 1 to 15), -CONH-, -NHCO-,
-CON (CH ₃ )-, -NH-, -O-, -CH ₂ O-, -COO-, or -OCO-, and A ₁ represents an oxygen atom or -COO- * (but the "*" bond is attached The junction is bonded to (CH ₂ ) _a2 ), A ₂ represents an oxygen atom or * -COO- (but the bond with "*" is bonded to (CH ₂ ) _a2 ), and a3 is 0 or An integer of 1, a1 and a2 are each independently an integer of 2 to 10, and Cy represents 1,4-cyclohexyl or 1,4-phenylene).

In a diamine having a side chain structure represented by the aforementioned formula [S2], X ³ is -CONH-, -NHCO-, -O-, -CH ₂ O-, -COO-, or -OCO-, R ² is preferably an alkyl group having 3 to 20 carbon atoms or an alkoxyalkyl group having 2 to 20 carbon atoms.

The side chain structure represented by the aforementioned formula [S3] preferably has a structure represented by the following formula [S3-x].

(In formula [S3-x], X represents formula [X1] or formula [X2], Col represents at least one selected from the group consisting of formulas [Col1] to [Col3], and G represents formula [G1] ~ Formula [G4], where * represents a bonding position).

It is preferable that the said diamine component contains at least 1 sort (s) chosen from the diamine represented by following formula [1] and [2].

(In the formula [2], X represents a single bond, -O-, -C (CH ₃ ) _2- , -NH-, -CO-,-(CH ₂ ) _m- , -SO ₂ -or the like Divalent organic groups formed by any combination, m is an integer of 1 to 8, and two Y's each independently represent at least one selected from the side chain structure represented by the aforementioned formulas [S1] to [S3], and, In the formula [1], Y represents at least one selected from the side chain structures represented by the aforementioned formulas [S1] to [S3].

The liquid crystal alignment film of the present invention that achieves the above-mentioned object is specifically obtained by using the liquid crystal alignment agent.

The liquid crystal display element of the present invention which achieves the above-mentioned object is characterized by including the liquid crystal alignment film.

[Effect of the invention]

According to the present invention, a liquid crystal alignment agent, a liquid crystal alignment film, and a liquid crystal display element can be provided which are capable of alleviating the accumulated charge for quickness and reliability (especially reliability after aging at high temperature and humidity), and for improvement.

[Best Mode for Implementing Invention]

Hereinafter, the present invention will be described in more detail.

The liquid crystal alignment agent of the present invention includes a polymer obtained by using a diamine component, and an organic solvent, the diamine component including a first diamine having a structure represented by the formula [I], and The second diamine compound having a side chain structure represented by S1] to [S3], first, the diamine will be described.

＜ First diamine compound ＞
The first diamine compound has a structure represented by the following formula [I].

(In the formula [I], Z ¹ represents an S atom or an O atom, * represents a site bonded to another group, and an arbitrary hydrogen atom of a benzene ring may be substituted with a monovalent organic group).

Examples of the monovalent organic group in the formula [I] include: a hydrocarbon group; a hydroxyl group, a carboxyl group, a hydrocarbon group including a hydroxyl group, a thiol group, or a carboxyl group; Linked hydrocarbon groups; silicon atom-containing hydrocarbon groups; halogenated hydrocarbon groups; amine groups; amine groups are inert groups protected by urethane-based protecting groups such as t-butoxycarbonyl and the like. However, the hydrocarbon group may be any of a straight chain, a branched chain, and a cyclic chain, and may be a saturated hydrocarbon or an unsaturated hydrocarbon. In addition, a part of the hydrogen atom of the hydrocarbon group may be substituted with a carboxyl group, a hydroxyl group, a thiol group, a silicon atom, a halogen atom, or the like, or may be connected by a bonding group such as an ether bond, an ester bond, or a amide bond.

The alkylene group having 1 to 3 carbon atoms may be any of a straight chain, a branched chain, and a cyclic chain. Specific examples include methylene, ethylidene, n-propylidene, isopropylidene, cyclodextyl, 1-methyl-dextyl, 2-methyl-dextyl , 1,1-dimethyl-n-propyl, 1,2-dimethyl-n-propyl, 2,2-dimethyl-n-propyl, 1-ethyl-n- Propane, 1,2-dimethyl-cyclopropane, 2,3-dimethyl-cyclopropane, 1-ethyl-cyclopropane, 2-ethyl-cyclopropane, 1,1,2-trimethyl-n-propyl, 1,2,2-trimethyl-n-propyl, 1-ethyl-1-methyl-n-propyl, 1- Ethyl-2-methyl-n-propyl, 2-n-propyl-cyclopropyl, 1-isopropyl-cyclopropyl, 2-isopropyl-cyclopropyl, 1, 2,2-trimethyl-cyclopropyl, 1,2,3-trimethyl-cyclopropyl, 2,2,3-trimethyl-cyclopropyl, 1-ethyl-2- Methyl-cyclopropane, 2-ethyl-1-methyl-cyclopropane, 2-ethyl-2-methyl-cyclopropane, and 2-ethyl-3-methyl-cyclopropane Propyl and so on.

Depending on the application, various monovalent organic groups or alkylene groups having 1 to 3 carbon atoms can be selected.

In the structure of the above formula [I], the bonding position of the benzene ring to the five-membered ring, as far as the point of charge movement, is represented by the following formula [I-1], is Z ¹ located on the five-membered ring. Carbon atoms of the next wall are preferred.

The specific first diamine compound may be represented by the following formula [I-2], for example, and preferably the diamine represented by the following formula [I-3], and more preferably the formula [I-4 ] Is a diamine.

In formulas [I-2] to [I-4], the definition of Z ¹ is the same as that in the case of the aforementioned formula [I], and Q ¹ and Q ² are each independently a single bond or a divalent organic group, that is, Q ¹ and Q ² may be mutually different structures. In addition, two Q ^{2 in} Formula [I-4] may have mutually different structures. Furthermore, as in the case of the above formula [I], an arbitrary hydrogen atom of the benzene ring may be substituted with a monovalent organic group.

As a preferable example of the said specific 1st diamine compound, the diamine represented by following formula [II] is mentioned, and the diamine represented by formula [II-1] is more preferable.

The definition of Z ¹ in the formula [II] and the formula [II-1] is the same as the formula [I]. The two P ² each independently represent a single bond or a structure of the following formula [III]. In the same manner as in the case of the above formula [I], an arbitrary hydrogen atom of a benzene ring may be substituted with a monovalent organic group.

In the above formula [III], P ³ represents a group selected from a single bond, -O-,
-COO-, -OCO-,-(CH ₂ ) _l- , -O (CH ₂ ) _m O-, -CONH-, and
Divalent organic group in the group formed by -NHCO-, where l and m represent integers of 1 to 5. Among them, in terms of relaxation of the accumulated charge, P ^{3 is} preferably a single bond, -O-, -COO-, -OCO-, -CONH-, or -NHCO-. In addition, * ₁ represents the site | part bonded to the benzene ring in Formula [2], and * ₂ represents the site | part bonded to the amine group in Formula [II].
N in the formula [II] and the formula [II-1] represents an integer of 1 to 3. It is preferably 1 or 2.

Specific examples of the diamine represented by the formula [II] include, but are not limited to, the diamine represented by the following formulas [4-1-1] to [4-1-12]. Among them, in terms of easing the accumulated charge, it is preferably [4-1-1], [4-1-2], [4-1-4] to [4-1-12], and particularly preferred is [4-1-1], [4-1-8] ~ [4-1-12].

＜ Synthesis method of the first diamine compound ＞
Next, the main synthesis method of the diamine of this invention is demonstrated. The method described below is a synthesis example and is not limited to this.

The diamine of the present invention can be obtained by reducing a dinitro compound and converting a nitro group into an amine group, as shown in the following reaction formula. In the following reaction formula, a diamine substituted with a hydrogen atom such as a benzene ring and a saturated hydrocarbon moiety other than a halogen atom such as a fluorine atom or a monovalent organic group other than an amine group is described as an example.

The method for reducing the dinitro compound is not particularly limited, and examples thereof include the use of palladium-carbon, platinum oxide, Raleigh nickel, platinum black, rhodium-alumina, platinum sulfide and the like as catalysts, and ethyl acetate, A method for reducing in solvents such as toluene, tetrahydrofuran, dioxane, and alcohols by hydrogen, hydrazine, hydrogen chloride, and the like. If necessary, an autoclave or the like may be used under pressure. On the other hand, when an unsaturated bond site is included in a substituent structure that replaces a hydrogen atom of a benzene ring or a saturated hydrocarbon portion, if palladium carbon or platinum carbon is used, the unsaturated bond site may be reduced to a saturated bond. Therefore, it is preferable to use reducing metals such as reduced iron, tin, and tin chloride as catalysts for the reduction conditions.

The above reaction can be performed in the presence of a base. The base used is not particularly limited as long as it can be synthesized, and examples include potassium carbonate, sodium carbonate, cesium carbonate, sodium alkoxide, potassium alkoxide, sodium hydroxide, and potassium hydroxide. , Inorganic bases such as sodium hydride, organic bases such as pyridine, dimethylaminopyridine, trimethylamine, triethylamine, tributylamine, and the like. In addition, depending on the case, when a palladium catalyst such as dibenzylideneacetone palladium or diphenylphosphinoferrocene palladium or a copper catalyst is used in combination, the yield can be improved.

The first diamine compound of the present invention obtained in this manner can be used as a polyimide precursor such as polyamic acid or polyamic acid ester, polyimide, polyurea, polyamidine, etc. These are collectively referred to as "polymers"). This polymer can be used as a liquid crystal alignment agent in a predetermined organic solvent, for example, but it is not limited to this application.

<Second diamine with a specific side chain structure>
In this embodiment, the second diamine system having a specific side chain structure is represented by, for example, the following formulas [1] and [2].

In the above formula [2], X represents a single bond, -O-,
-C (CH ₃ ) _2- , -NH-, -CO-, -NHCO-, -COO-,-(CH ₂ ) _m- ,
-SO ₂ -or a divalent organic group formed by any combination thereof. Among them, X is preferably a single bond, -O-, -NH-, -O- (CH ₂ ) _m -O-. Examples of "these arbitrary combinations" include -O- (CH ₂ ) _m -O-, -OC (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- and the like, but are not limited thereto. m is an integer from 1 to 8.

In the above formulas [1] and [2], Y independently represents at least one selected from the side chain structures represented by the formulas [S1] to [S3]. The details of the side chain structure represented by the formulas [S1] to [S3] will be described later.

In the above formula [2], the position of Y may be a meta position or an adjacent position from the position of X, and is preferably an adjacent position. That is, the above formula [2] is preferably the following formula [2 '].

In addition, in the above formula [2], the positions of the two amine groups (-NH ₂ ) may be any positions on the benzene ring, and are preferably represented by the following formulas [2] -a1 to [2] -a3 The position is preferably the following formula [2] -a1. In the following formula, X is the same as that in the above formula [2]. In addition, the following formulas [2] -a1 to [2] -a3 are for explaining the positions of two amine groups, and the symbol of Y shown in the above formula [2] is omitted.

Therefore, based on the above formulas [2 '] and [2] -a1 ~ [2] -a3, the above formula [2] is preferably selected from the following formulas [2] -a1-1 ~ [2] -a3-2 Any one of the structures is preferably a structure represented by the following formula [2] -a1-1. In the following formulae, X and Y are the same as those in the formula [2], respectively.

These two side chain diamines represented by the formula [2] may be used alone or in combination of two or more. Depending on the characteristics required for a liquid crystal alignment film or a liquid crystal display element, one type may be used alone or two or more types may be used in combination, and when two or more types are used in combination, the ratio and the like may be appropriately adjusted.

In the above formulae [1] and [2], Y represents a specific side chain structure selected from the group represented by the following formulae [S1] to [S3]. Hereinafter, the specific side chain structure will be described in the order of the formulas [S1] to [S3].

An example of the specific side chain structure is a diamine having a specific side chain structure represented by the following formula [S1].

In the above formula [S1], X ¹ and X ² each independently represent a single bond,-(CH ₂ ) _a- (a is an integer from 1 to 15), -CONH-, -NHCO-,
-CON (CH ₃ )-, -NH-, -O-, -COO-, -OCO- or
-((CH ₂ ) _a1 -A ₁ ) _m1- . Wherein the plurality of a1 are each independently an integer of 1 to 15, a plurality of A ₁ each independently represent an oxygen atom or -COO-, m ₁ is 1 to 2.

Among these, X ¹ and X ² are each independently preferably a single bond,-(CH ₂ ) _a- (a is an integer of 1 to 15), -O- from the viewpoint of availability of raw materials or ease of synthesis. , -CH ₂ O- or -COO-. Also preferably, X ¹ and X ² are each independently a single bond,-(CH ₂ ) _a- (a is an integer from 1 to 10), -O-, -CH ₂ O-, or
-COO-.

In the formula [S1], G ¹ and G ² each independently represent a divalent cyclic group selected from a divalent aromatic group having 6 to 12 carbon atoms or a divalent alicyclic group having 3 to 8 carbon atoms. Arbitrary hydrogen atoms on this cyclic group may be alkyl having 1 to 3 carbon atoms, alkoxy having 1 to 3 carbon atoms, fluorine-containing alkyl group having 1 to 3 carbon atoms, and fluorine containing 1 to 3 carbon atoms. Substituted by an alkoxy or fluorine atom. m and n are each independently an integer of 0 to 3 and the total of m and n is 1 to 4.

In the above formula [S1], 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 forms an arbitrary hydrogen of R ¹ Can be replaced by fluorine. Among them, examples of the divalent aromatic group having 6 to 12 carbon atoms include phenylene, phenylene, and naphthalene. Examples of the divalent alicyclic group having 3 to 8 carbon atoms include a cyclopropyl group and a cyclohexyl group.

Therefore, as a preferable specific example of the above-mentioned formula [S1], the following formulas [S1-x1] to [S1-x7] can be cited, but are not limited to these.

In the formulas [S1-x1] to [S1-x7], R ¹ is the same as that in the formula [S1]. X ^p represents-(CH ₂ ) _a- (a is an integer from 1 to 15),
-CONH-, -NHCO-, -CON (CH ₃ )-, -NH-, -O-, -CH ₂ O-,
-COO- or -OCO-. A ₁ represents an oxygen atom or -COO- * (the bonding portion with "*" is bonded to (CH ₂ ) _a2 ). A ₂ represents an oxygen atom or * -COO- (the bonding portion with "*" is bonded to (CH ₂ ) _a2 ). a ₃ is an integer of 0 or 1, and a ₁ and a ₂ are each independently an integer of 2-10. Cy, that is, a group described by "Cy" in a cyclohexane ring, represents 1,4-cyclohexyl or 1,4-phenylene.

An example of the specific side chain structure is a specific side chain structure represented by the following formula [S2].

In the above formula [S2], X ³ represents a single bond, -CONH-, -NHCO-,
-CON (CH ₃ )-, -NH-, -O-, -CH ₂ O-, -COO-, or -OCO-. Among them, from the viewpoint of liquid crystal alignment, X ^{3 is} preferably -CONH-,
-NHCO -, - 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 that forms R ² may be substituted with fluorine. Among these, from the viewpoint of liquid crystal alignment, R ^{2 is} preferably an alkyl group having 3 to 20 carbon atoms or an alkoxyalkyl group having 2 to 20 carbon atoms.

Furthermore, as an example of the specific side chain structure, a specific side chain structure represented by the following formula [S3] is mentioned.

In the above formula [S3], X ⁴ represents -CONH-, -NHCO-, -O-,
-COO- or -OCO-. R ³ represents a structure having a steroid skeleton. The steroid skeleton here is a skeleton represented by the following formula (st), which has three six-membered rings and one five-membered ring bonded.

As an example of the said formula [S3], although the following formula [S3-x] is mentioned, it is not limited to this.

In the formula [S3-x], X represents the formula [X1] or [X2]. In addition, Col represents at least one member selected from the group consisting of the formulas [Col1] to [Col3], and G represents at least one member selected from the group consisting of the formulas [G1] to [G4]. ＊ indicates a part bonded to another base.

Examples of preferred combinations of X, Col, and G in the above-mentioned formula [S3-x] include the combination of the formula [X1] and the formulas [Col1] and [G2]; the formula [X1] and the formula [ The combination of Col2] and [G2]; the combination of formula [X2] and [Col1] and [G2]; the combination of formula [X2] and [Col2] and [G2]; the formula [X1] and [Col3] And [G1].

Further, as a specific example of the formula [S3], a structure obtained by removing a hydroxy group from a steroid compound described in paragraph [0024] of Japanese Patent Application Laid-Open No. 4-281427 can be mentioned; A structure obtained by removing a chloro group from a steroid compound described in paragraph [0030]; a structure obtained by removing an amine group from a steroid compound described in paragraph [0038] of the same publication; and a steroid described in paragraph [0042] of the same publication A structure obtained by removing a halogen group from a compound; and a structure described in paragraphs [0018] to [0022] of Japanese Patent Application Laid-Open No. 8-146421.

These diamines having specific side chain structures represented by the above formulae [S1] to [S3] can be used alone or in combination of two or more. Depending on the characteristics required for a liquid crystal alignment film or a liquid crystal display element, one type may be used alone or two or more types may be used in combination, and when two or more types are used in combination, the ratio and the like may be appropriately adjusted.

As such, the diamine component of the present invention contains a diamine having a structure represented by the above formula [I] and a specific side chain selected from the group represented by the above formulas [S1] to [S3] Diamine made of at least one kind of structured diamine.

Among these, as the diamine having a side chain structure selected from the group represented by the above formulae [S1] to [S3], for example, there can be mentioned, for example, those having the following formulae [1-S1] to [1-S3] , [2-S1] ~ [2-S3] structure of the diamine.

In the formulae [1-S1] and [2-S1], X ¹ , X ² , G ¹ , G ² , R ¹ , m, and n are the same as those in the formula [S1]. In the formulas [1-S2] and [2-S2], X ³ and R ² are the same as those in the formula [S2]. In the formulas [1-S3] and [2-S3], X ⁴ and R ³ are the same as those in the formula [S3].

Among them, as the diamine represented by the above-mentioned formulas [1-S1] to [1-S3], for example, a specific structure as shown below may be mentioned, but it is not limited thereto.

Examples of the diamine represented by the formulae [2-S1] to [2-S3] include specific structures as shown below, but the invention is not limited thereto.

<Other diamines: diamines with photoreactive side chains>
The diamine component of this embodiment may contain the diamine which has a photoreactive side chain as another diamine. The diamine component contains a diamine having a photoreactive side chain, and a photoreactive side chain can be introduced into a specific polymer or a polymer other than the polymer.

Examples of the diamine having a photoreactive side chain include, but are not limited to, a diamine represented by the following formula [VIII] or [IX].

In the formulae [VIII] and [IX], the position of the two amine groups (-NH ₂ ) may be any position on the benzene ring. For example, a bond group with respect to a side chain may include a benzene ring. Position 2, 3, Position 2, 4, Position 2, 5, Position 2, 6, Position 3, 4, or Position 3, 5. The point of reactivity when synthesizing a polyamic acid is preferably a position of 2,4, a position of 2,5, or a position of 3,5. Considering the ease of synthesizing diamines, the positions of 2,4 and 3,5 are also preferred.

In the formula [VIII], R ⁸ represents a single bond, -CH _2- , -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-,
-CH ₂ O-, -N (CH ₃ )-, -CON (CH ₃ )-, or -N (CH ₃ ) CO-. In particular, R ^{8 is} preferably a single bond, -O-, -COO-, -NHCO-, or -CONH-.

In the formula [VIII], R ⁹ represents a single bond or an alkylene group having 1 to 20 carbon atoms which may be substituted with a fluorine atom. Alkylene
-CH ₂ -can be optionally substituted by -CF ₂ -or -CH = CH-, and if it is not adjacent to any of the following groups, it may be substituted by any of these groups: -O-,
-COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbocyclic or heterocyclic ring. The bivalent carbocyclic ring or heterocyclic ring can be specifically exemplified by the following formula (1a), but is not limited thereto.

In addition, in the formula [VIII], R ^{9 is} preferably a single bond or an alkylene group having 1 to 12 carbon atoms in terms of ease of formation and synthesis by a general organic synthesis method.

In the above formula [VIII], R ¹⁰ represents a photoreactive group selected from the group consisting of the following formula (1b). Among these, from the viewpoint of photoreactivity, R ^{10 is} preferably a methacryl group, acryl group, or a vinyl group.

In the formula [IX], Y ₁ represents -CH _2- , -O-,
-CONH-, -NHCO-, -COO-, -OCO-, -NH- or -CO-. Y ₂ represents an alkylene group having 1 to 30 carbon atoms, a divalent carbocyclic ring or a heterocyclic ring. Herein, one or a plurality of hydrogen atoms in the alkylene group, the divalent carbocyclic ring or the heterocyclic ring may be substituted with a fluorine atom or an organic group. If Y ₂ is not adjacent to the following bases,
-CH ₂ -can be replaced by: -O-, -NHCO-, -CONH-,
-COO-, -OCO-, -NH-, -NHCONH-, -CO-.

In the above formula [IX], Y ₃ represents -CH _2- , -O-,
-CONH-, -NHCO-, -COO-, -OCO-, -NH-, -CO- or a single bond. Y ₄ represents cassia hydrazone. Y ₅ represents a single bond, an alkylene group having 1 to 30 carbon atoms, a divalent carbocyclic ring or a heterocyclic ring. Herein, one or a plurality of hydrogen atoms in the alkylene group, the divalent carbocyclic ring or the heterocyclic ring may be substituted with a fluorine atom or an organic group. In Y ₅ , if the following groups are not adjacent to each other, -CH ₂ -may be replaced by these groups: -O-, -NHCO-, -CONH-, -COO-, -OCO-,- NH-,
-NHCONH-, -CO-. Y ₆ represents a photopolymerizable group such as acrylfluorenyl or methacrylfluorenyl.

As such a diamine having a photoreactive side chain represented by the above formula [VIII] or [IX], specific examples include the following formula (1c), but are not limited thereto.

In the formula (1c), X ⁹ and X ¹⁰ each independently represent a single bond, -O-, -COO-, -NHCO-, or -NH- (that is, a bonding group). Y represents an alkylene group having 1 to 20 carbon atoms which may be substituted by a fluorine atom.

Examples of the diamine having a photoreactive side chain include a diamine of the following formula [VII]. The diamine of the formula [VII] has a radical generating structure in a side chain. In the radical generating structure, ultraviolet rays are irradiated to decompose and generate radicals.

In the above formula [VII], Ar represents at least one aromatic hydrocarbon group selected from the group consisting of phenylene, naphthyl and phenylene. The hydrogen atoms of these rings may be replaced by halogen atoms. To replace. The carbonyl-bonded Ar system is related to the absorption wavelength of ultraviolet rays. Therefore, when a longer wavelength is used, a structure having a longer conjugated length such as a naphthyl group or a diphenyl group is preferred. On the other hand, if Ar has a structure such as a naphthyl group or a biphenyl group, the solubility may be deteriorated. In this case, the difficulty of synthesis will be increased. As long as it is in the range of 250 nm to 380 nm of the ultraviolet wavelength, sufficient characteristics can be obtained even with a phenyl group. Therefore, Ar is preferably a phenyl group.

In the Ar, a substituent may be provided on the aromatic hydrocarbon group. As examples of the substituent herein, an electron-donating organic group such as an alkyl group, a hydroxyl group, an alkoxy group, or an amine group is preferred.

In the formula [VII], R ₁ and R ₂ each independently represent an alkyl group having 1 to 10 carbon atoms, an alkoxy group, a benzyl group, or a phenethyl group. In the case of an alkyl group or an alkoxy group, a ring can be formed by R ₁ and R ₂ .

In the above formula [VII], T ₁ and T ₂ each independently represent a single bond, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-,
-CH ₂ O-, -N (CH ₃ )-, -CON (CH ₃ )-, or -N (CH ₃ ) CO- bonding group.

In Formula [VII], S represents a single bond, an unsubstituted or substituted carbon atom having 1 to 20 carbon atoms. Alkylene
-CH ₂ -or -CF ₂ -may be optionally substituted by -CH = CH-, and if it is not adjacent to any of the radicals listed below, it may be substituted by such radicals: -O- ,
-COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbocyclic ring, a divalent heterocyclic ring.

In the formula [VII], Q represents a structure selected from the following formula (1d).

In the formula (1d), R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. R ₃ represents -CH _2- , -NR-, -O-, or -S-.

In the above formula [VII], Q is preferably an electron-donating organic group, and an alkyl group, a hydroxyl group, an alkoxy group, an amine group, or the like is also preferred as exemplified in the example of Ar. When Q is an amine derivative, the polymerization of polyamic acid, which is a precursor of polyimide, may cause defects such as the formation of a salt between the carboxylic acid group and the amine group. Alkoxy is more preferred.

In the above formula [VII], the positions of the two amine groups (-NH ₂ ) may be any of o-phenylenediamine, m-phenylenediamine, or p-phenylenediamine, but In terms of reactivity with acid dianhydride, m-phenylene diamine or p-phenylene diamine is preferred.

Therefore, as a preferable specific example of the above-mentioned formula [VII], in terms of ease of synthesis, high versatility, characteristics, etc., the following formula can be cited. In the following formula, n is an integer of 2 to 8.

These diamines having a photoreactive side chain represented by the above formula [VII], [VIII], or [IX] may be used alone or in combination of two or more. Depending on the characteristics of liquid crystal alignment, pretilt angle, voltage holding characteristics, accumulated charge, etc. when the liquid crystal alignment film is made, the response speed of the liquid crystal when the liquid crystal display element is made, it can be used alone or as a mixture of two. When the above is used, and when two or more kinds are used in combination, the ratio and the like may be appropriately adjusted.

In this embodiment, if the diamine component includes a photoreactive side chain diamine, the photoreactive side chain diamine is preferably 10 to 70 mole% of the total diamine component, and 10 ~ 60 mol% is more preferred.

<Other diamines: Diamines other than the above>
Other diamines that can be contained in the diamine component used to obtain the specific polymer are not limited to the above-mentioned diamines having a photoreactive side chain and the like. Examples of the diamine other than the diamine having a photoreactive side chain include a diamine represented by the following formula [3].

In the above formula [3], A ₁ and A ₂ each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms or an alkynyl group having 2 to 5 carbon atoms. Among these, in terms of the reactivity of the monomers, A ₁ and A _{2 are} preferably a hydrogen atom or a methyl group. In the case of exemplifying the structure of Y ₁ , the following formulae (Y-1) to (Y-160), (Y-162) to (Y-168), and (Y-170) to (Y-174) ).

In the above formula, particularly regarding a structure in which a range of n is not described, n is an integer of 1 to 6. In the above formula, Me represents a methyl group.

In the above formula, Boc represents a tert-butoxycarbonyl group.

The other diamines including the diamine having a photoreactive side chain described above can be used in combination of one kind or two or more kinds. When the diamine component contains other diamines, the specific diamine in the specific polymer is preferably 10 mol% to 95 mol% of the total diamine component, and more preferably 20 mol% to 95 mol%.

<Tetracarboxylic acid component>
Examples of the tetracarboxylic acid component used to obtain the specific polymer include tetracarboxylic acid, tetracarboxylic dianhydride, tetracarboxylic dihalide, tetracarboxylic acid dialkyl, or tetracarboxylic acid dialkyl. Dihalides are also collectively referred to as tetracarboxylic acid components in the present invention.

As the tetracarboxylic acid component, a tetracarboxylic dianhydride or a derivative thereof, a tetracarboxylic acid, a tetracarboxylic acid dihalide, a tetracarboxylic acid dialkyl ester, or a tetracarboxylic acid dialkyl ester can be used. (These are collectively referred to as the first tetracarboxylic acid component).

Examples of the tetracarboxylic dianhydride include aliphatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, and aromatic tetracarboxylic dianhydride. Specific examples of these include the following groups [G-1] to [G-5].

As the [G-1] aliphatic tetracarboxylic dianhydride, for example, 1,2,3,4-butanetetracarboxylic dianhydride (1,2,3,4-butanetetracarboxylic dianhydride), etc .;

Examples of the [G-2] alicyclic tetracarboxylic dianhydride include acid dianhydrides such as the following formulae (X1-1) to (X1-13).

In the formulae (X1-1) to (X1-4), R ₃ to R ₂₃ each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, and a carbon number 2 An alkynyl group of ~ 6, a monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, or a phenyl group. R _M represents a hydrogen atom or a methyl group. In the formula (X1-13), Xa represents a tetravalent organic group represented by the following formulae (Xa-1) to (Xa-7).

[G-3] 3-oxabicyclo [3.2.1] octane-2,4-dione-6-spiro-3 '-(tetrahydrofuran-2', 5'-dione), 3,5, 6-tricarboxy-2-carboxymethylnorbornane-2: 3,5: 6-dianhydride, 4,9-dioxatricyclo [5.3.1.02,6] undecane-3,5,8 10-tetraketone, etc .;

[G-4] Pyrene is an aromatic tetracarboxylic dianhydride, for example, pyromite anhydride, 4,4 '-(hexafluoroisopropylidene) diphthalic anhydride, 3,3', 4,4 ' -Diphenylphosphonium tetracarboxylic dianhydride, acid dianhydride represented by the following formulae (Xb-1) to (Xb-10), etc., and

[G-5] An acid dianhydride represented by the formulae (X1-44) to (X1-52), a tetracarboxylic dianhydride described in Japanese Patent Application Laid-Open No. 2010-97188.

The tetracarboxylic acid components described above can be used alone or in combination of two or more. Depending on the characteristics required for a liquid crystal alignment film or a liquid crystal display element, one type may be used alone or two or more types may be used in combination, and when two or more types are used in combination, the ratio and the like may be appropriately adjusted.

＜ Manufacturing method of specific polymer ＞
The specific polymer is obtained by a method in which the diamine component (diamine component formed from a plurality of first diamines and second diamines) of the present embodiment described above is reacted with a tetracarboxylic acid component. . Examples of the method include a method in which a diamine component composed of one or more types of diamines is selected from the group consisting of a tetracarboxylic dianhydride and a derivative of a tetracarboxylic acid. A method in which at least one of the tetracarboxylic acid components is reacted to obtain polyamic acid. Specifically, a method of obtaining polyamic acid by polycondensing a first- or second-stage diamine with a tetracarboxylic dianhydride can be used.

In order to obtain polyalkylamino acid alkyl esters, a method of polycondensing a tetracarboxylic acid having a carboxylic acid group dialkylated and a first- or second-stage diamine can be used; and a halogenated carboxylic acid group can be used. A method of polycondensation of a tetracarboxylic acid dihalide and a first or second order diamine; a method of converting a carboxyl group of a polyamic acid into an ester. In order to obtain a polyimide, the method of making the said polyamic acid or a polyalkylamic acid alkyl ester ring-close | closing, and making it into a polyimide can be used.

The reaction of the diamine component and the tetracarboxylic acid component is usually carried out in a solvent. The solvent used at this time is not particularly limited as long as the produced polyfluorene imide precursor is a soluble solvent. Examples of the solvent include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone or γ-butyrolactone, N, N-dimethylformamidine, N, N-dimethylacetamidamine, dimethylsulfinium or 1,3-dimethyl-imidazolinone. When the solvent solubility of the polyimide precursor is high, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, or the following formula can be used. Solvents indicated by [D-1] to [D-3].

In the formula [D-1], D ¹ represents an alkyl group having 1 to 3 carbon atoms. In the formula [D-2], D ² represents an alkyl group having 1 to 3 carbon atoms. In 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 of two or more. Even if the polyimide precursor is a solvent that does not dissolve, as long as the produced polyimide precursor is within a range that does not precipitate, it can be mixed with the solvent and used. In addition, the water in the solvent will hinder the polymerization reaction and further cause the produced polyimide precursor to be hydrolyzed. Therefore, it is preferable to use a solvent that has been dehydrated and dried.

When the diamine component and the tetracarboxylic acid component are reacted in a solvent, the following method can be cited: dispersing or dissolving the diamine component in a solvent to obtain a solution and stirring, and then directly or dispersing or dissolving the tetracarboxylic acid component A method for adding to a diamine component solution after being in a solvent; conversely, a method for dispersing or dissolving a tetracarboxylic acid component in a solvent to obtain a solution, and then adding a diamine component to the solution; adding a diamine component alternately With the tetracarboxylic acid component method, these methods can be used. In addition, when a diamine component or a tetracarboxylic acid component is reacted by using a plurality of types, the reaction may be performed in a state of being mixed in advance, or the reactions may be individually performed sequentially, and further, the low The molecular weight is mixed to make a polymer.

The temperature at which the diamine component and the tetracarboxylic acid component are subjected to polycondensation polymerization may be selected at any temperature of -20 to 150 ° C, preferably in the range of -5 to 100 ° C. The reaction can be carried out at any concentration, but if the concentration is too low, it will be difficult to obtain a polymer with a high molecular weight. When the concentration is too high, the viscosity of the reaction solution will become too high, making it difficult to stir uniformly. Therefore, it is preferably 1 to 50% by mass, and still more preferably 5 to 30% by mass. It may be carried out at a high concentration at the beginning of the reaction, and then a solvent may be added later.

In the polymerization reaction of the polyfluorene imide precursor, the ratio of the total molar number of the diamine component to the total molar number of the tetracarboxylic acid component is preferably 0.8 to 1.2. It is the same as the ordinary polycondensation reaction. When the molar ratio is closer to 1.0, the molecular weight of the resulting polyfluorene imine precursor will increase.

Polyimide is a polyimide obtained by closing the polyimide precursor. The polyimide has a ring closure ratio (also called amidation ratio) of amidate groups. It is 100% and can be adjusted arbitrarily according to the use or purpose. Examples of the method for polyimide precursor polyimide include thermally imidizing the solution of the polyimide precursor directly, or adding a catalyst to the polyimide precursor. The catalyst in the solution of the substance is imidized.

In the case where the polyfluorene imine precursor is subjected to thermal hydrazone imidization in a solution, the temperature is 100 to 400 ° C, preferably 120 to 250 ° C, so as to simultaneously carry out water generated by the hydrazone imidization reaction. It is better to remove to the outside. Polyimide precursor catalyst 醯 imidization can be performed by adding alkaline catalyst and anhydride to the solution of polyimide precursor, and stirring at -20 ~ 250 ℃, preferably 0 ~ 180 ℃ .

The amount of alkaline catalyst is 0.5 to 30 mol times, preferably 2 to 20 mol times, and the amount of acid anhydride is 1 to 50 mol times, preferably 3 to 30 mol times. 30 mol times. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine. Among them, a pyridine system is preferred because it has a moderate basicity during the reaction. Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, and pyromelite dianhydride. In particular, when acetic anhydride is used, it is preferable to facilitate purification after completion of the reaction. The rate of amidine imidation obtained by catalyst amidine imidization can be controlled by adjusting the amount of catalyst, 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 poured into a solvent to precipitate. Examples of the solvent used for the precipitation include methanol, ethanol, isopropanol, acetone, hexane, butyl cyrus, heptane, methyl ethyl ketone, methyl isobutyl ketone, toluene, benzene, and water. After the polymer which was put into the solvent and precipitated was collected by filtration, the polymer may be dried under normal pressure or reduced pressure, or at normal temperature or by heating. In addition, the polymer recovered by precipitation is re-dissolved in a solvent, and if the operation of re-precipitation recovery is repeated 2 to 10 times, impurities in the polymer can be reduced. Examples of the solvent at this time include alcohols, ketones, and hydrocarbons. When three or more solvents selected from these are used, it is preferable because the efficiency of purification can be further improved.

Examples of more specific methods for producing the polyalkylamino alkyl esters of the present invention are shown in the following (1) to (3), respectively.

(1) Production method by esterification reaction of polyamic acid The method is, for example, producing polyamino acid from a diamine component and a tetracarboxylic acid component, and chemically reacting the carboxyl group (COOH group) (that is, , To perform an esterification reaction) to produce a polyalkylamino alkyl ester. The esterification reaction is to react the polyamidic acid and the esterifying agent at -20 to 150 ° C (preferably 0 to 50 ° C) for 30 minutes to 24 hours (preferably 1 to 4 hours) in the presence of a solvent. .

The esterification agent is preferably one which can be easily removed after the esterification reaction, and examples thereof include N, N-dimethylformamide dimethyl acetal and N, N-dimethylformamide diamine. Ethyl acetal, N, N-dimethylformamide dipropyl acetal, N, N-dimethylformamide dineopentylbutyl acetal, N, N-dimethylformamide Di-t-butyl acetal, 1-methyl-3-p-tolyltriazene, 1-ethyl-3-p-tolyltriazene, 1-propyl-3-p-tolyl Triazene, 4- (4,6-dimethoxy-1,3,5-triazin-2-yl) -4-methyl morpholine chloride and the like. The use amount of the esterifying agent is preferably 2 to 6 mol equivalents relative to the repeating unit of the polyamic acid. Among them, 2 to 4 mole equivalents are preferred.

Examples of the solvent used in the above-mentioned esterification reaction include the solvent used in the reaction between the diamine component and the tetracarboxylic acid component in terms of the solubility of polyamic acid in the solvent. Among them, N, N-dimethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone or γ-butyrolactone is preferred. These solvents may be used singly or in combination of two or more kinds. The concentration of the polyamic acid in the solvent of the above-mentioned esterification reaction is preferably 1 to 30% by mass from the point that the precipitation of the polyamic acid is not easily caused. Among them, 5 to 20% by mass is preferred.

(2) A method for producing by reacting a diamine component with a tetracarboxylic acid diester dichloride. This method is, for example, combining a diamine component and a tetracarboxylic acid diester dichloride in the presence of a base and a solvent, with- A method of reacting at 20 to 150 ° C (preferably 0 to 50 ° C) for 30 minutes to 24 hours (preferably 1 to 4 hours). As the base, pyridine, triethylamine, 4-dimethylaminopyridine, and the like can be used. Among these, in order to carry out the reaction stably, pyridine is preferable. The amount of the base used is preferably an amount that can be easily removed after the reaction, and is preferably 2 to 4 times moles relative to the tetracarboxylic acid diester dichloride. Among them, 2 to 3 times the mole is more preferable.

Regarding the solvent, in terms of the solubility of the obtained polymer (that is, the polyalkylamic acid alkyl ester) with respect to the solvent, a solvent used in the reaction between the diamine component and the tetracarboxylic acid component is mentioned. Among them, N, N-dimethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone or γ-butyrolactone is preferred. These solvents can be used alone or in combination of two or more.

The concentration of the polyalkylamic acid alkyl ester in the reaction solvent is preferably 1 to 30% by mass from the point that precipitation of the polyalkylamic acid alkyl ester is not easily caused. Among them, 5 to 20% by mass is preferred. In addition, in order to prevent the hydrolysis of the tetracarboxylic acid diester dichloride, it is preferable that the solvent used in the production of the polyalkylamino acid alkyl ester be dehydrated as much as possible. Furthermore, the reaction is carried out in a nitrogen environment, and it is preferable to prevent outside air from being mixed.

(3) Production method by reaction of a diamine component and a tetracarboxylic acid diester The method is, for example, the diamine component and a tetracarboxylic acid diester in the presence of a condensation agent, a base, and a solvent at a temperature of 0 to 150 ° C. (Preferably 0 to 100 ° C) a method of polycondensation reaction for 30 minutes to 24 hours (preferably 3 to 15 hours).

As the condensing agent, triphenylphosphite, dicyclohexylcarbodiimide, 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride, N can be used. , N'-carbonyldiimidazole, dimethoxy-1,3,5-triazinylmethylmorpholinium, O- (benzotriazol-1-yl) -N, N, N ', N '-Tetramethylurea tetrafluoroborate, O- (benzotriazol-1-yl) -N, N, N', N'-tetramethylurea hexafluorophosphate, (2,3-dihydro 2-thio-3-benzoxazolyl) diphenylphosphonate and the like. The use amount of the condensing agent is preferably 2 to 3 times mole, particularly 2 to 2.5 times mole, relative to the tetracarboxylic acid diester.

As the base, tertiary amines such as pyridine and triethylamine can be used. The amount of the base used is preferably an amount that can be easily removed after the polycondensation reaction, and is preferably 2 to 4 times mole compared to the diamine component, and more preferably 2 to 3 times mole. Examples of the solvent used for the polycondensation reaction in terms of the solubility of the obtained polymer (that is, polyalkylamino acid alkyl ester) with respect to the solvent include those used for the diamine component and the tetracarboxylic acid component. Solvents in the reaction. Among them, N, N-dimethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone or γ-butyrolactone is preferred. These solvents can be used singly or in combination of two or more kinds.

In addition, by adding a Lewis acid as an additive in the polycondensation reaction, the reaction can be efficiently performed. The Lewis acid is preferably a lithium halide such as lithium chloride or lithium bromide. The amount of the Lewis acid to be used is preferably 0.1 to 10 times the mole of the diamine component. Among them, 2.0 to 3.0 times the mole is preferred.

When the polyalkylamino acid alkyl ester is recovered from the solution of the polyalkylamino acid ester obtained by the methods (1) to (3) described above, the reaction solution may be added to a solvent to precipitate it. Examples of the solvent used for the precipitation include water, methanol, ethanol, 2-propanol, hexane, butylcellulose, acetone, and toluene. In order to remove the additives and catalysts used for the polymer which is put into the solvent and precipitated, it is preferable to perform the washing operation with the above solvent multiple times. After washing, filtering, and recovering, the polymer can be dried under normal pressure or reduced pressure, or at normal temperature or by heating. In addition, if the polymer recovered by precipitation is re-dissolved in a solvent and the operation of re-precipitation and recovery is repeated 2 to 10 times, impurities in the polymer can be reduced. The polyalkylamino acid ester is preferably produced by the above-mentioned (2) or (3).

＜ Liquid crystal alignment agent ＞
The liquid crystal alignment agent of the present invention contains the specific polymer described above, but may contain two or more kinds of specific polymers having different structures. In addition to the specific polymer, other polymers (that is, polymers that do not have a divalent group represented by formula (I) (that is, those obtained without the specific diamine represented by formula [I]) polymer)). Examples of the polymer include polyamic acid, polyimide, polyamidate, polyester, polyamidine, polyurea, polyorganosiloxane, cellulose derivative, polyacetal, Polystyrene or a derivative thereof, poly (styrene-phenylmaleimide) derivative, poly (meth) acrylate, and the like. When the liquid crystal alignment agent of the present invention contains other polymers, the proportion of the specific polymer is preferably 5% by mass or more with respect to the entire polymer component, and may be, for example, 5 to 95% by mass.

The liquid crystal alignment agent is generally in the form of a coating liquid in terms of forming a uniform thin film. The liquid crystal alignment agent of the present invention is also preferably a coating liquid containing the polymer component and an organic solvent capable of dissolving the polymer component. At this time, the concentration of the polymer in the liquid crystal alignment agent can be appropriately changed according to the thickness of the coating film to be formed. In terms of forming a uniform and defect-free coating film, it is preferably 1% by mass or more, and in terms of storage stability of the solution, 10% by mass or less is preferable. The concentration of the particularly good polymer is 2 to 8% by mass.

The organic solvent contained in the liquid crystal alignment agent is not particularly limited as long as it can dissolve the polymer component uniformly. If specific examples are given, such as N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidine Ketones, dimethyl sulfene, γ-butyrolactone, 1,3-dimethyl-imidazolinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, and the like. Among these, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, or γ-butyrolactone is preferably used.

In addition, in addition to the above solvents, the organic solvent contained in the liquid crystal alignment agent of the present invention may be a solvent that can improve the coating property or the surface smoothness of the coating film when the liquid crystal alignment agent is applied. The following are specific examples of the organic solvent, but are not limited thereto.

For example: ethanol, isopropanol, 1-butanol, 2-butanol, isobutanol, tert-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1 -Butanol, isoamyl alcohol, tert-pentanol, 3-methyl-2-butanol, neopentyl alcohol, 1-hexanol, 2-methyl-1-pentanol, 2-methyl-2- Amyl alcohol, 2-ethyl-1-butanol, 1-heptanol, 2-heptanol, 3-heptanol, 1-octanol, 2-octanol, 2-ethyl-1-hexanol, cyclohexanol Alcohol, 1-methylcyclohexanol, 2-methylcyclohexanol, 3-methylcyclohexanol, 2,6-dimethyl-4-heptanol, 1,2-ethylene glycol, 1,2 -Propylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 2 -Methyl-2,4-pentanediol, 2-ethyl-1,3-hexanediol, diisopropyl ether, dipropyl ether, dibutyl ether, dihexyl ether, dioxane, ethyl Glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, 1,2-butoxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether , 4-hydroxy-4-methyl-2-pentanone, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, 2-pentanone, 3-pentanone, 2-hexanone, 2 -Heptanone, 4-heptanone, 2,6-dimethyl-4- Ketone, 4,6-dimethyl-2-heptanone, 3-ethoxybutyl acetate, 1-methylpentyl acetate, 2-ethylbutyl acetate, 2-ethyl Hexyl acetate, ethylene glycol monoacetate, ethylene glycol diacetate, propylene carbonate, ethyl carbonate, 2- (methoxymethoxy) ethanol, ethylene glycol monobutyl ether , Ethylene glycol monoisoamyl ether, ethylene glycol monohexyl ether, 2- (hexyloxy) ethanol, furfuryl alcohol, diethylene glycol, propylene glycol, propylene glycol monobutyl ether, 1- (butoxyethoxy ) Propanol, propylene glycol monomethyl ether acetate, dipropylene glycol, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol Dimethyl ether, tripropylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monoethyl ether Acid ester, ethylene glycol diacetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 2- (2-ethoxyethoxy) ethyl ethyl Acid ester, diethylene glycol acetate, triethylene glycol, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether Ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate , Ethyl 3-ethoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, 3 -Propyl methoxypropionate, butyl 3-methoxypropionate, methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, isoamyl lactate, according to the above formula [D- 1] ~ [D-3] Solvents etc.

Among them, organic solvents are 1-hexanol, cyclohexanol, 1,2-ethylene glycol, 1,2-propylene glycol, propylene glycol monobutyl ether, diethylene glycol diethyl ether, and 4-hydroxy-4. -Methyl-2-pentanone, ethylene glycol monobutyl ether or dipropylene glycol dimethyl ether is preferred. The type and content of such a solvent can be appropriately selected depending on the coating device, coating conditions, coating environment, and the like of the liquid crystal alignment agent.

The liquid crystal alignment agent of the present invention may further contain components other than the polymer component and the organic solvent. Examples of such additional components include adhesion promoters for improving the adhesion between the liquid crystal alignment film and the substrate, or adhesion between the liquid crystal alignment film and the sealing material, and the improvement of the strength of the liquid crystal alignment film. Crosslinking agents, dielectric materials or conductive materials used to adjust the dielectric constant or resistance of liquid crystal alignment films. Specific examples of such additional components include the poor solvents or crosslinkable compounds disclosed in paragraphs [0104] to page 60, paragraph [0116] of International Publication No. 2015/060357.

The liquid crystal alignment agent of the present invention may contain, in addition to the above, a polymer other than the specific polymer described in the present invention, a dielectric substance for the purpose of changing electrical characteristics such as the dielectric constant and conductivity of the liquid crystal alignment film, A silane coupling agent for the purpose of improving the adhesion between the liquid crystal alignment film and the substrate, a crosslinkable compound for the purpose of improving the film hardness or density when the liquid crystal alignment film is made, and further achieving a coating film during firing In the case of polyimide precursors, the polyimide precursors can be efficiently carried out at the time, and the imidation accelerator can be used for the purpose of imidation by heating.

Examples of the compound for improving the adhesion between the liquid crystal alignment film and the substrate include functional silane-containing compounds or epoxy-containing compounds, such as 3-aminopropyltrimethoxysilane and 3-aminopropyltriamine. Ethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane , 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2 -Aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidotriethoxysilane, N-ethoxycarbonyl-3 -Aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxy Silylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane , 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonylethyl Ester, N-benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane , N-phenyl-3-aminopropyltriethoxysilane, N-bis (oxyethylene) -3-aminopropyltrimethoxysilane, N-bis (oxyethylene) -3 -Aminopropyltriethoxysilane, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl Glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, 2,2-dibromo neopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl ether Glyceryl-2,4-hexanediol, N, N, N ', N',-tetraglycidyl-m-xylylenediamine, 1,3-bis (N, N-diglycidylamino) (Methyl) cyclohexane or N, N, N ', N',-tetraglycidyl-4, 4'-diaminodiphenylmethane and the like.

In addition, the liquid crystal alignment agent of the present invention may be used to increase the mechanical strength of the liquid crystal alignment film, and additives such as the following may be added.

The aforementioned additive is preferably 0.1 to 30 parts by mass relative to 100 parts by mass of the polymer component contained in the liquid crystal alignment agent. If it is less than 0.1 parts by mass, this effect cannot be expected, and if it exceeds 30 parts by mass, the alignment of the liquid crystal will be lowered, so it is more preferably 0.5 to 20 parts by mass.

＜ Liquid crystal alignment film ＞
The liquid crystal alignment film of the present invention is obtained by using the liquid crystal alignment agent. By using the liquid crystal alignment agent of the present invention, particularly the VA method (especially the PSA mode) suitable for a method in which liquid crystal molecules in a vertical alignment with respect to a substrate responds by an electric field, can provide an excellent voltage retention rate and an accumulated charge. The relaxation is a liquid crystal alignment film or a liquid crystal display element which is fast and has excellent afterimage characteristics. If an example of a method for obtaining a liquid crystal alignment film is given, after applying the liquid crystal alignment agent of the present invention to a substrate, it is dried and fired as required to obtain a cured film, and the cured film is directly used as a liquid crystal alignment film. Yes. The cured film may be rubbed or irradiated with polarized light or light of a specific wavelength, or treated with an ion beam, or irradiated with a voltage applied to the liquid crystal display element after filling the liquid crystal as an alignment film for PSA. UV. In particular, it can be used as an alignment film for PSA.

The substrate for applying the liquid crystal alignment agent is not particularly limited as long as it is a substrate having high transparency, and a plastic substrate such as an acrylic substrate or a polycarbonate substrate can be used together with a glass substrate or a silicon nitride substrate. At this time, in terms of simplification of the process, it is preferable to use a substrate formed with an ITO electrode or the like for liquid crystal driving. Further, in a reflective liquid crystal display element, if only one substrate is used, an opaque object such as a silicon wafer may be used, and in this case, an electrode such as aluminum that reflects light may be used.

The coating method of the liquid crystal alignment agent is not particularly limited, and it is generally screen printing, lithography, flexographic printing, inkjet, etc. in the industry. As other coating methods, such as a dip method, a roll coater method, a slit coater method, a spin coater method, a spray method, etc., these can be used according to the purpose. After the liquid crystal alignment agent is applied to the substrate, the solvent is evaporated and fired by heating means such as a hot plate, a thermal cycle type oven, and an IR (infrared) type oven. Steps of drying and firing after applying the liquid crystal alignment agent can be selected at any temperature and time. The drying step is not necessary, but if the entire substrate is not constant within a period from coating to firing, or if firing is not performed directly after coating, the drying step is preferred. This drying is only required to remove the solvent to such an extent that the shape of the coating film does not deform due to the transportation of the substrate or the like, and the drying means is not particularly limited. Examples thereof include a method of drying on a hot plate at a temperature of 40 ° C. to 150 ° C. (preferably 60 ° C. to 100 ° C.) for 0.5 to 30 minutes (preferably 1 to 5 minutes).

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

If the thickness of the fired liquid crystal alignment film is too thin, the reliability of the liquid crystal display element may be reduced. Therefore, it is preferably 5 to 300 nm, and more preferably 10 to 200 nm. As the liquid crystal alignment film of the present invention, a liquid crystal alignment film that is a liquid crystal display element of the VA method (particularly, the PSA mode) can be used.

<Liquid crystal display element and manufacturing method thereof>
The liquid crystal display element can be formed into a liquid crystal cell by a well-known method after forming a liquid crystal alignment film on a substrate according to the method described above. A specific example of the liquid crystal display device is a liquid crystal display device having a vertical alignment method including a liquid crystal cell. The liquid crystal display device includes two substrates arranged in an opposite manner, a liquid crystal layer provided between the substrates, and a substrate and a liquid crystal. The liquid crystal alignment film formed between the layers by a liquid crystal alignment agent. Specifically, it is a liquid crystal display element having a vertical alignment method including a liquid crystal cell. The liquid crystal alignment agent is coated on two substrates and fired to form a liquid crystal alignment film. The liquid crystal alignment film is opposed to the liquid crystal alignment film. Two substrates are arranged, a liquid crystal layer composed of liquid crystal is sandwiched between the two substrates (that is, a liquid crystal layer is provided by contacting the liquid crystal alignment film), and the liquid crystal alignment film and the liquid crystal layer are irradiated with ultraviolet rays while applying a voltage. To make.

The substrate of the liquid crystal display element is not particularly limited as long as it is a substrate having high transparency, but is usually a substrate having a transparent electrode for driving liquid crystals formed on the substrate. As a specific example, the same as the substrate described in the above-mentioned liquid crystal alignment film can be exemplified. Although a conventional substrate provided with an electrode pattern or a projection pattern can be used, in a liquid crystal display element, a liquid crystal alignment agent containing the polyfluorene-imide polymer of the present invention is used, and even if it is formed on a single-sided substrate, for example, 1 μm A line / slit electrode pattern of ~ 10 μm, and a structure in which no slit pattern or protrusion pattern is formed on the opposite substrate can also be operated. With the structure of the liquid crystal display element, the manufacturing process at the time of manufacturing can be simplified and high transmittance can be obtained. .

Further, in a high-performance element such as a TFT-type element, a member that forms an element like a transistor between an electrode for liquid crystal driving and a substrate can be used.

In the case of a transmissive liquid crystal display element, a substrate as described above is generally used, but for a reflective liquid crystal display element, if only one substrate is used, an opaque substrate such as a silicon wafer may be used. At this time, the electrode formed on the substrate may also use a material that reflects light, such as aluminum.

The liquid crystal material constituting the liquid crystal layer of the liquid crystal display element is not particularly limited, and conventional liquid crystal materials used in the vertical alignment method can be used, for example, negative liquid crystals such as MLC-6608, MLC-6609, and MLC-3023 manufactured by Merck. . In the PSA mode, for example, a liquid crystal containing a polymerizable compound represented by the following formula can be used.

As a method of sandwiching a liquid crystal layer between two substrates, a known method can be exemplified. For example, the following method can be mentioned: a pair of substrates on which a liquid crystal alignment film is formed is prepared, and spacers such as beads are dispersed on the liquid crystal alignment film of one substrate, so that the surface on the side where the liquid crystal alignment film is formed is located on the inner side. Method to attach another substrate, inject liquid crystal under reduced pressure, and seal. In addition, a liquid crystal cell can be prepared by the following method, and a pair of substrates on which a liquid crystal alignment film is formed is prepared. A spacer such as beads is dispersed on a liquid crystal alignment film of a substrate, and the liquid crystal is dropped, and then formed into The one side of the liquid crystal alignment film is placed inside so that the other substrate is bonded and sealed. The thickness of the spacer is preferably 1 to 30 μm, and more preferably 2 to 10 μm.

The step of producing a liquid crystal cell by applying a voltage to the liquid crystal alignment film and the liquid crystal layer while irradiating ultraviolet rays can be exemplified by the following method: by applying a voltage between the electrodes provided on the substrate, the liquid crystal alignment film is applied. An electric field is applied to the liquid crystal layer, and ultraviolet rays are irradiated while the electric field is maintained. Here, the voltage applied between the electrodes is, for example, 5 to 30 Vp-p, and preferably 5 to 20 Vp-p. The amount of ultraviolet radiation is, for example, 1 to 60 J, and preferably 40 J or less. If the amount of ultraviolet radiation is small, the decrease in reliability caused by the destruction of the components constituting the liquid crystal display element can be suppressed, and the ultraviolet irradiation time can be reduced. It is suitable for improving manufacturing efficiency.

As described above, when a voltage is applied to the liquid crystal alignment film and the liquid crystal layer while irradiating ultraviolet rays, the polymerizable compound reacts to form a polymer, and the polymer can memorize the oblique direction of the liquid crystal molecules, which can accelerate the obtained Response speed of liquid crystal display elements. When applying a voltage to the liquid crystal alignment film and the liquid crystal layer while irradiating ultraviolet rays, the liquid crystal alignment film and the liquid crystal layer are selected from a polyimide precursor having a side chain orienting the liquid crystal vertically and a photoreactive side chain, and a polyimide precursor At least one of the polyfluorene imines obtained by amidine imidization reacts with the photoreactive side chains of the polymer, or the photoreactive side chains of the polymer react with the polymerizable compound. The response speed of the obtained liquid crystal display element can be accelerated.

Next, set the polarizing plate. Specifically, it is preferable that a pair of polarizing plates is bonded to a surface opposite to the liquid crystal layer of the two substrates.

The liquid crystal alignment film and the liquid crystal display element of the present invention are not limited to the above-mentioned structure or manufacturing method as long as the liquid crystal alignment agent of the present invention is used, and other well-known methods can also be used for production. Steps until a liquid crystal display element is obtained from a liquid crystal alignment agent are disclosed in, for example, paragraph [0074] on page 17 to paragraph [0082] on page 19 in Japanese Patent Application Laid-Open No. 2015-135393.

When the polymer has a photoreactive side chain, the polymerizable compound is polymerized and the photoreactive side chains are reacted with each other, or the photoreactive side chain that the polymer has is reacted with the polymerizable compound. Therefore, the liquid crystal alignment can be more efficiently fixed and a liquid crystal display element having an excellent response speed can be obtained.

[Example]

The following examples are given to explain the present invention in more detail, but the present invention is not limited to such a progressive explanation. The compounds used are as follows.

≫Synthesis example of 1st amine≫
＜ Organic solvents ＞
NMP: N-methyl-2-pyrrolidone
NEP: N-ethyl-2-pyrrolidone
GBL: γ-butyrolactone
BCS: butyl cellosolve
PB: propylene glycol monobutyl ether
DME: Dipropylene glycol dimethyl ether
DAA: 4-hydroxy-4-methyl-2-pentanone
DEDG: Diethylene glycol diethyl ether
DIBK: 2,6-dimethyl-4-heptanone
DIPE: Diisopropyl ether
DIBC: 2,6-dimethyl-4-heptanol
Pd / C: Palladium Carbon
DMSO: Dimethyl sulfene
THF: tetrahydrofuran

＜ Additives ＞
LS-4668: 3-glycidoxypropyltriethoxysilane

( ¹ H-NMR measurement)
Equipment: Varian NMR system 400NB (400MHz) (made by Varian) and JMTC-500 / 54 / SS (500MHz) (made by JEOL)
Measurement solvents: CDCl ₃ (deuterated chloroform), DMSO-d ₆ (deuterated dimethyl sulfene)
Reference materials: TMS (tetramethylsilane) (δ: 0.0 ppm, ¹ H) and CDCl ₃ (δ: 77.0 ppm, ¹³ C)

＜ Synthesis of the first diamine (DA-1) ＞

In a 2 L (liter) four-necked flask, 2,5-dibromothiophene (50 g, 208 mmol), 4-nitrophenylboronic acid (72.9 g, 436 mmol), sodium carbonate (110 g, 1040 mmol), and dimethyl Methylformamide (500 g), pure water (100 g). Thereafter, triphenylphosphine palladium (2.5 g) was added at room temperature under a nitrogen atmosphere, the temperature was raised to 100 ° C, and the mixture was stirred for 48 hours. After confirming the completion of the reaction by HPLC (high performance liquid chromatography), the obtained solid was filtered under reduced pressure, and reslurried with pure water (500 g). The precipitated crystals were filtered under reduced pressure, reslurried and washed with acetonitrile (350 g), 80 ° C, and dried to obtain powder crystals (1) (yield 42 g, yield 50%).
The NMR measurement results are as follows.
1H-NMR (DMSO-d ₆ ): 8.32-8.28 (4H, m), 8.03-8.00 (4H, m), 7.94 (2H, s)

A mixture of compound (1) (20 g, 61.3 mmol), 5 mass% Pt / C (50% water-containing type), activated carbon (2.0 g), and dioxane (100 g) was added under a hydrogen pressure condition at 80 Stir at 24 ° C for 24 hours. After the reaction was completed, the catalyst was filtered and then concentrated to dryness. The obtained solid was recrystallized with ethyl acetate (200 g) and toluene (200 g), and the precipitated crystals were filtered under reduced pressure, washed with methanol (50 g), and dried to obtain powder crystal DA-1. (Yield: 8 g, yield: 50%).
The NMR measurement results are as follows.
1H-NMR (DMSO-d ₆ ): 7.34-7.27 (4H, m), 7.09 (2H, s), 7.09-6.55 (4H, m), 5.28 (4H, s)

＜ Synthesis of the first diamine (DA-2) ＞

In a 3 L (liter) four-necked flask, zinc chloride (120.3 g, 882 mmol) was added, the temperature was raised to 100 ° C, and vacuum drying was performed by an oil pump for 1 hour. Then, at room temperature under a nitrogen environment, toluene (460 g), diethylamine (45.0 g, 615 mmol), t-butanol (46.4 g, 626 mmol), and 2-bromo-4-nitrophenylethyl were sequentially added. Ketone (100.0 g, 410 mmol) and 4-nitroacetophenone (104.2 g, 631 mmol) were stirred at room temperature for 3 days. After confirming the completion of the reaction by HPLC (high performance liquid chromatography), a 5% sulfuric acid aqueous solution (400 g) was added and neutralized, and the mixture was stirred at room temperature for 1 hour. The precipitated crystals were filtered under reduced pressure, washed with toluene (200 g), pure water (300 g), and methanol (200 g) and then dried to obtain crude crystals. Tetrahydrofuran (1340 g) was used to dissolve all the obtained crude crystals, and then ethanol (1340 g) was added, followed by stirring at 5 ° C for 1 hour. The precipitated crystals were filtered under reduced pressure, washed with ethanol (200 g), and dried to obtain powder crystals (1) (yield 63 g, yield 45%).
The NMR measurement results are as follows.
1H-NMR (DMSO-d ₆ ): 8.40-8.36 (4H, m), 8.28-8.24 (4H, m), 3.53 (4H, s)

A 2 L (liter) four-necked flask was charged with compound (1) (50 g, 152 mmol), acetic anhydride (1000 g), and sulfuric acid (10 g) and acetic anhydride (200 g) were added dropwise. After the dropwise addition was completed, the temperature was raised to 140 ° C, and the mixture was stirred for 3 hours. After confirming the completion of the reaction by HPLC (high performance liquid chromatography), the reaction solution was added to cold water (5000 g) and stirred for 1 hour. The precipitated crystals were filtered under reduced pressure, reslurried and washed with acetonitrile (500 g) at 80 ° C, and dried to obtain powder crystals (2) (yield 42 g, yield 90%).
The NMR measurement results are as follows.
1H-NMR (DMSO-d ₆ ): 8.34-8.31 (4H, m), 8.16-8.13 (4H, m), 7.56 (2H, s)

A mixture of compound (2) (40 g, 129 mmol), 5 mass% Pt / C (50% water-containing type), activated carbon (4.0 g), and tetrahydrofuran (400 g) was stirred at 60 ° C. under a hydrogen pressure condition for 12 hours. hour. After the reaction was completed, the catalyst was filtered and then concentrated to dryness. The obtained solid was recrystallized from acetonitrile (400 g), and the precipitated crystals were filtered under reduced pressure, washed with methanol (50 g), and dried to obtain powder crystal DA-2 (yield 20 g, yield). 77%).
The NMR measurement results are as follows.
1H-NMR (DMSO-d ₆ ): 7.42-7.38 (4H, m), 6.61-6.56 (6H, m), 5.28 (2H, s)

≫Synthesis Example of Poly 醯 imide-based Polymer≫
In the following, DA-2 (ie, [A1]) synthesized in the above Synthesis Example, [A2] synthesized in the same manner, and DA-1 (ie, [A3]) synthesized in the above Synthesis Example are used as follows. Synthesis of polyfluorene imide polymers.

(liquid crystal)
MLC-3023 (Merck, liquid crystal containing negative polymerizable compound)

(1st diamine)
Compounds represented by the following formulas [A1] to [A3]
A1: Compound represented by formula [A1]
A2: Compound represented by formula [A2]
A3: Compound represented by formula [A3]

(Second Diamine)
Compounds represented by the following formulas [B1] to [B3]
B1: Compound represented by formula [B1]
B2: Compound represented by formula [B2]
B3: Compound represented by formula [B3]

(Other diamine ingredients)
Compounds represented by the following formulas [C1] to [C6]
C1: Compound represented by formula [C1]
C2: Compound represented by formula [C2]
C3: Compound represented by formula [C3]
C4: Compound represented by formula [C4]
C5: Compound represented by formula [C5]
C6: a compound represented by the formula [C6]

(Tetracarboxylic acid component)
Compounds represented by the following formulas [D1] to [D4]
D1: 1,2,3,4-cyclobutane tetracarboxylic dianhydride
D2: Bicyclic [3,3,0] octane-2,4,6,8-tetracarboxylic dianhydride
D3: TCA
D4: BTDA

(Solvent)
NMP: N-methyl-2-pyrrolidone
BCS: ethylene glycol monobutyl ether

(Determination of the ratio of amidine imidization of polyimide)
20 mg of polyfluorene imine powder was put into an NMR (nuclear magnetic resonance) sample tube (NMR sampling tube stand, ϕ5 (manufactured by Kusano Science Co., Ltd.)), and deuterated dimethylimide (DMSO-d ₆ , 0.05 mass% TMS) (Tetramethylsilane) (0.53ml), and completely dissolved by ultrasonic. This solution was measured with a NMR measuring machine (JNW-ECA500) (manufactured by JEOL DATUM) at 500 MHz for proton NMR. The hydrazone imidization rate uses protons from a structure that does not change before and after hydrazone imidization as the reference protons. The cumulative peak value of the protons is used to compare the NH groups from hydrazones that appear near 9.5 to 10.0 ppm. The cumulative value of the proton peak is obtained by the following formula.
醯 Imidization rate (%) = (1-α ・ x / y) × 100
In the above formula, x is the cumulative value of the proton peaks of the NH group derived from ammonium acid, y is the cumulative value of the peaks of the standard protons, and α is relative to 醯Proportion of the number of reference protons per NH matrix proton of amino acid.

(Viscosity measurement)
In the synthesis example or comparative synthesis example, the viscosity of the polyfluorene-imide polymer was measured using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.) with a sample volume of 1.1 mL and a tapered rotor TE-1 (1 ° 34 ', R24), and a temperature of 25 ° C.

＜ Synthesis of Polyfluorene-based Polymers ＞
The synthesis of the polyfluorene-imide-based polymer was performed as described below. The results are shown in Table 1.

[Synthesis example 1]
After D2 (2.50 g, 10.0 mmol), A1 (3.50 g, 14.0 mmol), and B1 (2.28 g, 6.00 mmol) were mixed in NMP (39.9 g) and reacted at 50 ° C for 3 hours, D1 ( 1.69 g, 8.60 mmol), and reacted at 40 ° C. for 3 hours to obtain a polyamic acid solution having a resin solid content concentration of 20% by mass. When the viscosity of this polyamic acid solution was measured, it was 756 mPa.s.
NMP was added to the obtained polyamidic acid solution (20.0g) and diluted to 6.5% by mass, and then acetic anhydride (3.984g) and pyridine (1.24g) were added as the imidization catalyst, and the temperature was changed to 50 ° C. Allow to react for 3 hours. This reaction solution was poured into methanol (234 ml), and the obtained precipitate was collected by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyfluorene imide powder (1). The polyimide has a fluorene imidization rate of 51%.

[Synthesis example 2]
D2 (2.50 g, 10.0 mmol), A1 (2.00 g, 8.00 mmol), B1 (2.28 g, 6.00 mmol), C1 (0.65 g, 6.00 mmol) were mixed in NMP (36.7 g), and the temperature was adjusted at 50 ° C. After reacting for 3 hours, D1 (1.75 g, 8.90 mmol) was added and reacted at 40 ° C. for 3 hours to obtain a polyamic acid solution having a resin solid content concentration of 20% by mass. When the viscosity of this polyamic acid solution was measured, it was 717 mPa.s.
After adding NMP to the obtained polyamidic acid solution (20.0 g) and diluting it to 6.5% by mass, acetic anhydride (4.35 g) and pyridine (1.35 g) were added as the phosphonium imidization catalyst. The reaction was allowed to proceed at 3 ° C for 3 hours. This reaction solution was poured into methanol (235 ml), and the obtained precipitate was collected by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyfluorene imide powder (2). The polyimide has a fluorene imidization rate of 51%.

[Synthesis example 3]
D2 (2.50 g, 10.0 mmol), A1 (2.00 g, 8.00 mmol), B1 (2.28 g, 6.00 mmol), C2 (2.05 g, 6.00 mmol) were mixed in NMP (42.6 g), and the temperature was adjusted at 50 ° C. After reacting for 3 hours, D1 (1.81 g, 9.24 mmol) was added and reacted at 40 ° C. for 3 hours to obtain a polyamic acid solution having a resin solid content concentration of 20% by mass. When the viscosity of this polyamic acid solution was measured, it was 784 mPa.s.
After adding NMP to the obtained polyamidic acid solution (20.0 g) and diluting it to 6.5% by mass, acetic anhydride (3.78 g) and pyridine (1.17 g) as the phosphonium imidization catalyst were added, and The reaction was allowed to proceed at 3 ° C for 3 hours. This reaction solution was poured into methanol (233 ml), and the obtained precipitate was collected by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyfluorene imide powder (3). The polyimide has a fluorene imidation rate of 60%.

[Synthesis example 4]
D2 (2.50 g, 10.0 mmol), A1 (3.50 g, 14.0 mmol), B2 (3.03 g, 4.00 mmol), C3 (0.66 g, 2.00 mmol) were mixed in NMP (45.7 g), and the mixture was allowed to stand at 50 ° C. After reacting for 3 hours, D1 (1.73 g, 8.80 mmol) was added and reacted at 40 ° C. for 3 hours to obtain a polyamic acid solution having a resin solid content concentration of 20% by mass. When the viscosity of this polyamic acid solution was measured, it was 990 mPa.s.
NMP was added to the obtained polyamidic acid solution (20.0g) and diluted to 6.5% by mass, and then acetic anhydride (3.50g) and pyridine (1.09g) were added as the imidization catalyst, and the content was adjusted to 50%. The reaction was allowed to proceed at 3 ° C for 3 hours. This reaction solution was poured into methanol (265 ml), and the obtained precipitate was collected by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyfluorene imide powder (4). The polyimide has a fluorene imidization rate of 54%.

[Synthesis example 5]
After D2 (2.50 g, 10.0 mmol), A2 (3.50 g, 14.0 mmol), and B1 (2.28 g, 6.00 mmol) were mixed in NMP (41.0 g) and reacted at 50 ° C for 3 hours, D1 ( 1.95 g, 9.96 mmol), and reacted at 40 ° C. for 3 hours to obtain a polyamic acid solution having a resin solid content concentration of 20% by mass. When the viscosity of this polyamic acid solution was measured, it was 374 mPa.s.
After adding NMP to the obtained polyamidic acid solution (20.0 g) and diluting it to 6.5% by mass, acetic anhydride (3.98 g) and pyridine (1.24 g) of the imidization catalyst were added, and the temperature was changed to 50 ° C. Allow to react for 3 hours. This reaction solution was poured into methanol (234 ml), and the obtained precipitate was collected by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyfluorene imide powder (5). The polyimide has a fluorene imidization rate of 59%.

[Synthesis example 6]
D3 (4.44 g, 19.8 mmol), A1 (2.00 g, 8.00 mmol), B1 (2.28 g, 6.00 mmol), C1 (0.65 g, 6.00 mmol) were mixed in NMP (37.5 g), and the temperature was adjusted at 60 ° C. This reaction was carried out for 6 hours to obtain a polyamic acid solution having a resin solid content concentration of 20% by mass. When the viscosity of this polyamic acid solution was measured, it was 834 mPa.s.
NMP was added to the obtained polyamidic acid solution (20.0 g) and diluted to 6.5% by mass, and then acetic anhydride (4.34 g) and pyridine (1.34 g) were added as the phosphonium imidization catalyst. The reaction was allowed to proceed at 3 ° C for 3 hours. This reaction solution was poured into methanol (336 ml), and the obtained precipitate was collected by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyfluorene imide powder (6). The polyimide has a fluorinated imidization rate of 45%.

[Synthesis example 7]
After D2 (2.50 g, 10.0 mmol), A1 (3.50 g, 14.0 mmol), and B3 (2.61 g, 6.00 mmol) were mixed in NMP (41.7 g) and reacted at 50 ° C for 3 hours, D1 ( 1.80 g, 9.20 mmol) and reacted at 40 ° C. for 3 hours to obtain a polyamic acid solution having a resin solid content concentration of 20% by mass. When the viscosity of this polyamic acid solution was measured, it was 761 mPa.s.
NMP was added to the obtained polyamic acid solution (20.0 g) and diluted to 6.5% by mass, and then acetic anhydride (3.86 g) and pyridine (1.20 g) were added as the fluorinated imidization catalyst. The reaction was allowed to proceed at 3 ° C for 3 hours. This reaction solution was poured into methanol (266 ml), and the obtained precipitate was collected by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyfluorene imide powder (7). The polyimide has a fluorene imidization rate of 55%.

[Synthesis example 8]
D2 (2.50 g, 10.0 mmol), A1 (2.00 g, 8.00 mmol), B1 (2.28 g, 6.00 mmol), C1 (0.65 g, 6.00 mmol) were mixed in NMP (39.9 g), and the temperature was adjusted at 50 ° C. After reacting for 3 hours, D4 (1.92 g, 6.00 mmol) was added and reacted at 23 ° C. for 1 hour, and D1 (0.61 g, 3.10 mmol) was further added to react at 23 ° C. for 3 hours to obtain a solid resin. A 20% by mass polyamic acid solution. When the viscosity of this polyamic acid solution was measured, it was 805 mPa.s.
After adding NMP to the obtained polyamidic acid solution (20.0 g) and diluting it to 6.5% by mass, acetic anhydride (4.02 g) and pyridine (1.25 g) were added as the phosphonium imidization catalyst. The reaction was allowed to proceed at 3 ° C for 3 hours. This reaction solution was poured into methanol (234 ml), and the obtained precipitate was collected by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyfluorene imide powder (8). The polyimide has a hydrazone imidation rate of 47%.

[Synthesis example 9]
D2 (2.50 g, 10.0 mmol), A3 (2.13 g, 8.00 mmol), B1 (2.28 g, 6.00 mmol), C6 (0.65 g, 6.00 mmol) were mixed in NMP (37.2 g), and the temperature was adjusted at 50 ° C. After reacting for 3 hours, D1 (1.74 g, 8.83 mmol) was added and reacted at 40 ° C. for 3 hours to obtain a polyamic acid solution having a resin solid content concentration of 20% by mass. When the viscosity of this polyamic acid solution was measured, it was 833 mPa.s.
After adding NMP to the obtained polyamidic acid solution (20.0 g) and diluting it to 6.5% by mass, acetic anhydride (4.29 g) and pyridine (1.33 g) as the phosphonium imidization catalyst were added, and The reaction was allowed to proceed at 3 ° C for 3 hours. This reaction solution was poured into methanol (403 ml), and the obtained precipitate was collected by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyfluorene imide powder (9). The polyimide has a fluorene imidization rate of 50%.

[Comparative Synthesis Example 1]
After D2 (2.50 g, 10.0 mmol), B1 (2.28 g, 6.00 mmol), and C5 (3.49 g, 14.0 mmol) were mixed in NMP (40.2 g) and reacted at 50 ° C for 3 hours, D1 ( 1.76 g, 9.00 mmol), and reacted at 40 ° C. for 3 hours to obtain a polyamic acid solution having a resin solid content concentration of 20% by mass. When the viscosity of this polyamic acid solution was measured, it was 758 mPa.s.
After adding NMP to the obtained polyamidic acid solution (20.0 g) and diluting it to 6.5% by mass, acetic anhydride (3.99 g) and pyridine (1.24 g) as the phosphonium imidization catalyst were added, and The reaction was allowed to proceed at 3 ° C for 3 hours. This reaction solution was poured into methanol (234 ml), and the obtained precipitate was collected by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyfluorene imide powder (R1). The polyimide has a fluorene imidation ratio of 46%.

[Comparative Synthesis Example 2]
D2 (2.50 g, 10.0 mmol), B1 (2.28 g, 6.00 mmol), C1 (0.65 g, 6.00 mmol), C4 (1.99 g, 8.00 mmol) were mixed in NMP (36.8 g), and the temperature was adjusted at 50 ° C. After reacting for 3 hours, D1 (1.76 g, 9.0 mmol) was added and reacted at 40 ° C. for 3 hours to obtain a polyamic acid solution having a resin solid content concentration of 20% by mass. When the viscosity of this polyamic acid solution was measured, it was 786 mPa.s.
After adding NMP to the obtained polyamidic acid solution (20.0 g) and diluting it to 6.5% by mass, acetic anhydride (4.35 g) and pyridine (1.35 g) were added as the phosphonium imidization catalyst. The reaction was allowed to proceed at 3 ° C for 3 hours. This reaction solution was poured into methanol (235 ml), and the obtained precipitate was collected by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyfluorene imide powder (R2). The polyimide has a fluorene imidization rate of 52%.

＜ Modulation of liquid crystal alignment agent ＞
The examples and comparative examples describe preparation examples of the liquid crystal alignment agent. The liquid crystal alignment agent obtained in the Example and the comparative example was used for manufacture of a liquid crystal display element, and various evaluations.

<Example 1>
To the polyfluorene imine powder (1) (3.00 g) obtained in Synthesis Example 1, NMP (27.0 g) was added, and the mixture was dissolved by stirring at 70 ° C for 24 hours. BCS (20.0 g) was added to this solution to obtain a liquid crystal alignment agent (V-1). No abnormality such as turbidity or precipitation was found in the liquid crystal alignment agent, and it was confirmed that the liquid crystal alignment agent was a uniform solution.

<Example 2> to <Example 8>
The liquid crystal alignment agents (V-2) to (V-8) were obtained in the same manner as in Example 1 except that the polyfluorene imine powders (2) to (8) were prepared. No abnormality such as turbidity or precipitation was found in the liquid crystal alignment agent, and it was confirmed that the liquid crystal alignment agent was a uniform solution.

<Example 9>
To the polyfluorene imine powder (9) (3.00 g) obtained in Synthesis Example 9, NMP (57.0 g) was added, and the mixture was stirred at 70 ° C for 24 hours to dissolve. To this solution, BCS (15.0 g) was added to obtain a liquid crystal alignment agent (V-9). No abnormality such as turbidity or precipitation was found in the liquid crystal alignment agent, and it was confirmed that the liquid crystal alignment agent was a uniform solution.

〈Comparative example 1〉
To the polyfluorene imide powder (R1) (3.00 g) obtained in Comparative Synthesis Example 1, NMP (27.0 g) and BCS (20.0 g) were added and stirred at 70 ° C for 24 hours to obtain a liquid crystal alignment agent (V- R1). No abnormality such as turbidity or precipitation was found in the liquid crystal alignment agent, and it was confirmed that the liquid crystal alignment agent was a uniform solution.

〈Comparative example 2〉
A liquid crystal alignment agent (V-R2) was obtained in the same manner as in Comparative Example 1 except that the polyfluorene imine powder (R2) was prepared. No abnormality such as turbidity or precipitation was found in the liquid crystal alignment agent, and it was confirmed that the liquid crystal alignment agent was a uniform solution.

<Example 10>
The liquid crystal alignment agent (V-4) (3.00 g) obtained in Example 4 and the liquid crystal alignment agent (V-R1) (7.00 g) obtained in Comparative Example 1 were mixed and stirred at room temperature for 3 hours to obtain a liquid crystal. Aligning agent (V-10). No abnormality such as turbidity or precipitation was found in the liquid crystal alignment agent, and it was confirmed that the liquid crystal alignment agent was a uniform solution.

<Example 11>
Except changing the liquid crystal alignment agent used in Example 6 to the liquid crystal alignment agent (V-6) (3.00 g) obtained in Example 6 and the liquid crystal alignment agent (V-R2) (7.00 g) obtained in Comparative Example 2, The same operation as in Example 10 was performed to obtain a liquid crystal alignment agent (V-11).

Using the obtained liquid crystal alignment agents (V-1) to (V-11), a liquid crystal display element was produced and a liquid crystal display element was produced, and evaluation of vertical alignment, evaluation of voltage holding ratio, and evaluation of afterimage characteristics were performed. The results are shown in Table 2.

In addition, liquid crystal display elements (V-R1) to (V-R2) of the comparative examples were used to fabricate a liquid crystal display element, and evaluation of vertical alignment, evaluation of voltage holding ratio, and evaluation of afterimage characteristics were performed. The results are shown in Table 2.

＜ Production of liquid crystal display element for evaluation ＞
The liquid crystal alignment agents (V-1) to (V-11) obtained in the examples and the liquid crystal alignment agents (V-R1) to (V-R2) obtained in the comparative examples were added using a thin-film filter having a pore size of 1 μm. Filtered. The obtained solution was spin-coated on the ITO surface of a 40 mm × 30 mm glass substrate with an ITO electrode (length: 40 mm, width: 30 mm, thickness: 1.1 mm) which had been washed with pure water and IPA (isopropyl alcohol). The ITO substrate with a liquid crystal alignment film with a thickness of 100 nm was obtained by heating at 70 ° C. for 90 seconds on a hot plate and 230 minutes at 230 ° C. for a thermal cycle type clean oven. Two pieces of the obtained ITO substrate with a liquid crystal alignment film were prepared, and a bead spacer with a diameter of 4 μm was coated on the liquid crystal alignment film surface of one of the substrates (Nippon Kasei Kasei Kasei Corporation, silk ball, SW-D1) .

Next, the surroundings were coated with a sealant (XN-1500T manufactured by Mitsui Chemicals). Next, the side where the liquid crystal alignment film is formed on the other substrate is used as the inner side, and after bonding to the previous substrate, the sealant is hardened to produce an empty cell. Liquid crystal MLC-3023 (trade name, manufactured by Merck) was injected into the empty cell by a reduced pressure injection method to prepare a liquid crystal cell.

In a state where a DC voltage of 15 V was applied to the liquid crystal cell, UV (1st-UV) of a high-pressure mercury lamp passing through a filter of 325 nm or less at 10 J / cm ² was irradiated from the outside of the liquid crystal cell. Thereafter, without applying a voltage to the liquid crystal cell, a fluorescent UV lamp (FLR40SUV32 / A-1) was used for 30 minutes (2nd-UV) to passivate the unreacted polymerizable compound existing in the liquid crystal cell. . In addition, the measurement of the amount of ultraviolet irradiation was performed by connecting a UV-35 photoreceptor to UV-M03A manufactured by ORC Corporation.

＜ Evaluation ＞
(Vertical alignment)
The liquid crystal alignment of the liquid crystal display device was observed with a polarizing microscope (ECLIPSE E600WPOL) (manufactured by Nikon Corporation) to confirm whether the liquid crystal was vertically aligned. Specifically, those in which defects caused by the flow of liquid crystals or bright spots caused by alignment defects are not found are good. The evaluation results are shown in Table 2.

(reliability)
The voltage retention rate (%) after the release of the application of the liquid crystal display element for evaluation prepared above as described above at an application time of 60 microseconds and an interval of 1667 milliseconds was measured at 60 ° C at 60 ° C. Thereafter, it was left in a high-temperature, high-humidity oven at 85 ° C for 8 days, and the voltage retention rate (%) was measured at 60 ° C in the same manner. As the measurement device, VHR-1 manufactured by TOYO Corporation was used. The evaluation results are shown in Table 2. A voltage retention rate of 40% or more after a high-temperature and high-humidity test was regarded as good, and a case of less than 40% was regarded as defective.

(Afterimage characteristics)
Using the prepared liquid crystal display element for evaluation, an AC voltage of 7.8 Vp-p (30 Hz) and a DC voltage of 3 V were applied and driven at a temperature of 23 ° C for 96 hours. Thereafter, the voltage (residual DC) generated in the liquid crystal cell immediately after the DC voltage was released and after 3 hours was determined by the scintillation erasing method. The results are shown in Table 2. The residual DC voltage accumulated immediately after the DC voltage was released was considered to be good if the residual DC voltage was 70 mV or less after 3 hours, and poor if the accumulated DC voltage was 70 mV or more.

Claims (10)

A liquid crystal alignment agent comprising a polymer obtained by using a diamine component and an organic solvent, the diamine component including at least one kind of a first diamine represented by the following formula [I], and At least one of the second diamines in the side chain structure of the group represented by the following formulae [S1] to [S3], (In the formula [I], Z ¹ represents an S atom or an O atom, * represents a site bonded to another group, and an arbitrary hydrogen atom of a benzene ring may be substituted by a monovalent organic group) (In the formula [S1], X ¹ and X ² each independently represent a single bond,-(CH ₂ ) _a- (a is an integer of 1 to 15), -CONH-, -NHCO-, -COs-NH-,- O -, - COO-, -OCO- or _{- ((CH 2) a1 -A} 1) m1 -, wherein the plurality of a1 are each independently an integer of 1 to 15, a plurality of a ₁ each independently represent an oxygen atom or a - COO-, m ₁ is 1 to 2, G ¹ and G ² each independently represent a divalent cyclic group selected from a divalent aromatic group having 6 to 12 carbon atoms or a divalent alicyclic group having 3 to 8 carbon atoms An arbitrary hydrogen atom on the aforementioned cyclic group may be selected from 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, and 1 to 3 carbon atoms. Substituted by at least one of the group consisting of a fluorine-containing alkoxy group or a fluorine atom, m and n are each independently an integer of 0 to 3 and the total of m and n is 1 to 4, R ¹ represents a carbon number of 1 ~ 20 alkyl groups, 1 ~ 20 carbon alkoxy groups, or 2 ~ 20 carbon alkoxyalkyl groups, any hydrogen forming R ¹ may be replaced by fluorine) (In formula [S2], 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 forming R ² may be substituted by fluorine) (In the formula [S3], X ⁴ represents -CONH-, -NHCO-, -O-, -COO-, or -OCO-, and R ³ represents a structure having a steroid skeleton). The liquid crystal alignment agent according to claim 1, wherein the polymer is at least one polymer selected from the group consisting of a polyimide precursor and a polyimide that is a polyimide, the polymer The polyfluorene imide precursor is a condensation polymer obtained by using a diamine having a structure represented by the formula [I] and a tetracarboxylic dianhydride. The liquid crystal alignment agent according to claim 1, wherein the first diamine is represented by the following formula [II], (In the formula [II], the definition of Z ¹ is the same as the above formula [I], P ² independently represents a single bond or the structure of the following formula [II-1], n represents an integer of 1 to 3, and a benzene ring (Any hydrogen atom can be replaced by a monovalent organic group) (Formula [II-1] in, P ³ represents a group selected single bond, -O -, - COO -, - OCO-, - (CH 2) l -, - O (CH 2) m O -, - CONH- And -NHCO- divalent organic groups (l and m represent integers from 1 to 5), * ₁ represents a site bonded to a benzene ring in formula [II], and * ₂ represents an amine with formula [II] Base bond). The liquid crystal alignment agent according to claim 2, wherein the first diamine is represented by the following formula [II], (In the formula [II], the definition of Z ¹ is the same as the above formula [I], P ² independently represents a single bond or the structure of the following formula [II-1], n represents an integer of 1 to 3, and a benzene ring (Any hydrogen atom can be replaced by a monovalent organic group) (Formula [II-1] in, P ³ represents a group selected single bond, -O -, - COO -, - OCO-, - (CH 2) l -, - O (CH 2) m O -, - CONH- And -NHCO- divalent organic groups (l and m represent integers from 1 to 5), * ₁ represents a site bonded to a benzene ring in formula [II], and * ₂ represents an amine with formula [II] Base bond). The liquid crystal alignment agent according to any one of claims 1 to 4, wherein the side chain structure represented by the aforementioned formula [S1] is selected from the group consisting of the following formulas [S1-x1] to [S1-x7] At least 1 in the group, (In the formulae [S1-x1] to [S1-x7], R ¹ represents an alkyl group having 1 to 20 carbon atoms, and X ^p represents-(CH ₂ ) _a- (a is an integer of 1 to 15), -CONH- , -NHCO-, -CON (CH ₃ )-, -NH-, -O-, -CH ₂ O-, -COO-, or -OCO-, A ₁ represents an oxygen atom or -COO- * (but, with "*" Is bonded to (CH ₂ ) _a2 ), and A ₂ represents an oxygen atom or * -COO- (but the "*" bonded portion is bonded to (CH ₂ ) _a2 ) , A3 is an integer of 0 or 1, a1 and a2 are each independently an integer of 2 to 10, and Cy represents 1,4-cyclohexyl or 1,4-phenylene). The liquid crystal alignment agent according to any one of claims 1 to 4, wherein in a diamine having a side chain structure represented by the aforementioned formula [S2], X ³ is -CONH-, -NHCO-, -O- , -CH ₂ O-, -COO-, or -OCO-, and R ² is an alkyl group having 3 to 20 carbon atoms or an alkoxyalkyl group having 2 to 20 carbon atoms. The liquid crystal alignment agent according to any one of claims 1 to 4, wherein the side chain structure represented by the aforementioned formula [S3] has a structure represented by the following formula [S3-x], (In formula [S3-x], X represents formula [X1] or formula [X2], Col represents at least one selected from the group consisting of formulas [Col1] to [Col3], and G represents formula [G1] ~ Formula [G4], where * represents a bonding position). The liquid crystal alignment agent according to any one of claims 1 to 4, wherein the diamine component contains at least one selected from the diamines represented by the following formulas [1] and [2], (In formula [1], Y represents at least one selected from the side chain structures represented by the aforementioned formulas [S1] to [S3], and in formula [2], X represents a single bond, -O-, -C (CH ₃ ) _2- , -NH-, -CO-,-(CH ₂ ) _m- , -SO ₂ -or any combination thereof, m is an integer from 1 to 8, 2 Each Y independently represents at least one selected from the side chain structures represented by the aforementioned formulas [S1] to [S3]. A liquid crystal alignment film is specifically obtained by using the liquid crystal alignment agent according to any one of claim 1 to claim 8. A liquid crystal display element is characterized by including a liquid crystal alignment film of claim 8.