TWI865463B - Diamine compound, polymer, liquid crystal alignment agent, liquid crystal alignment film and liquid crystal display device - Google Patents

Abstract

A diamine compound, a polymer, a liquid crystal alignment agent, a liquid crystal alignment film and a liquid crystal display device are provided. The diamine compound is a diamine compound (b1-1) represented by formula (I). The polymer (A-1) is obtained by reacting a first mixture. The first mixture includes a tetracarboxylic dianhydride compound (a1) and a diamine compound (b1), wherein the diamine compound (b1) includes the diamine compound (b1-1) represented by formula (I). A liquid crystal alignment agent includes the polymer (A-1) and a solvent (B).

Description

Diamine compound, polymer, liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element

The present invention relates to a diamine compound, a polymer, a liquid crystal alignment agent, a liquid crystal alignment film and a liquid crystal display element, and in particular to a diamine compound, a polymer, a liquid crystal alignment agent, a liquid crystal alignment film and a liquid crystal display element that can be used to produce a liquid crystal display element with good electric field memory effect and environmental resistance.

As working modes of liquid crystal display elements, various liquid crystal display elements are known, such as twisted nematic (TN) type or super twisted nematic (STN) type, vertical alignment (VA) type, in-plane switching (IPS) type, fringe field switching (FFS) type, optically compensated bend (OCB) type, etc., which use liquid crystal molecules with positive dielectric anisotropy. In order to control the alignment of each liquid crystal molecule, a liquid crystal alignment film formed of an organic film is mainly used (patent documents 1 to 4).

Since the liquid crystal molecules of the above-mentioned TN type, STN type and other liquid crystal alignment films respond quickly, and the above-mentioned VA type and other liquid crystal alignment films have a certain tilt direction when the liquid crystal is driven, they each need to have a pre-tilt angle characteristic. As a method of imparting a pre-tilt angle characteristic, in the case of the former, it is usually a friction method, and in the case of the latter, it is usually a friction method, or a method of providing protrusions on the surface of the substrate. The dust or static electricity generated in the friction method step sometimes causes problems such as poor display or circuit damage. On the other hand, the method of providing protrusions on the surface of the substrate sometimes damages the brightness of the resulting liquid crystal display element, so these methods all have problems.

Therefore, as a method of providing a pre-tilt angle instead of these methods, a so-called photo-alignment method has been proposed in which a photosensitive film is irradiated with ultraviolet rays in a direction tilted relative to the film normal line (Patent Document 5). However, a liquid crystal display element manufactured using the liquid crystal alignment agent described in Patent Document 5 has problems such as electric field memory effect and poor environmental resistance of the liquid crystal display element, which is not conducive to application.

On the other hand, as a method of imparting liquid crystal alignment ability to a coating film formed by a liquid crystal alignment agent containing polyamide, etc., in recent years, a photoalignment method using photoisomerization, photodimerization, photodecomposition, etc. has been proposed as a technology to replace the friction method. The photoalignment method is a method in which anisotropy is imparted to a radiation-sensitive organic thin film formed on a substrate by irradiating the film with polarized or non-polarized radiation, thereby controlling the alignment of liquid crystal molecules. According to this method, compared with the previous friction method, the generation of dust or static electricity in the step can be suppressed, thereby suppressing the generation of poor display or a decrease in yield caused by dust, etc. In addition, it also has the advantage of being able to uniformly impart liquid crystal alignment ability to an organic thin film formed on a substrate.

Specifically, the technical literature of the photoalignment method is Patent Document 6. Patent Document 6 proposes a liquid crystal alignment agent having a conjugated enone repeating unit and an imide structure. However, the liquid crystal display element made with the liquid crystal alignment agent described in Patent Document 6 also has the problem of poor electric field memory effect and environmental resistance of the liquid crystal display element. [Prior technical literature] [Patent literature] [Patent literature 1] Japanese Patent Publication No. 56-91277 [Patent literature 2] Japanese Patent Publication No. 1-120528 [Patent literature 3] Japanese Patent Publication No. 11-258605 [Patent literature 4] Japanese Patent Publication No. 2002-250924 [Patent literature 5] Japanese Patent Publication No. 2004-83810 [Patent literature 6] Japanese Patent Publication No. 2005-037654

Therefore, how to improve the electric field memory effect and poor environmental resistance of liquid crystal display elements to meet the current industry requirements is a problem that technicians in this field are eager to solve.

In view of this, the present invention provides a diamine compound that can form a polymer. The polymer can be used to make a liquid crystal alignment agent and a liquid crystal alignment film for a liquid crystal display element, which can improve the electric field memory effect and poor environmental resistance of the above-mentioned liquid crystal display element.

The present invention provides a diamine compound, which is a diamine compound (b1-1) represented by formula (I). Formula (I): In formula (I), ^X1 and ^X2 each independently represent a single bond, , , , , , , , , , or , wherein R ¹⁴ represents hydrogen or an alkyl group having 1 to 4 carbon atoms; x represents 0 or 1; y represents an integer from 0 to 4; R ¹ represents a methylene group or an alkylene group having 2 to 4 carbon atoms; R ³ each independently represents an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a halogen atom or a cyano group; R ² represents an organic group represented by formula (IA) or a monovalent organic group having a steroid skeleton and having 17 to 40 carbon atoms; Formula (IA): In formula (IA), ^R4 represents fluorine or methyl; ^R5 , ^R6 and ^R7 each independently represent a single bond, -O-, , , , , , methylene or an alkylene radical having 2 to 3 carbon atoms; R ⁸ represents or , wherein R ¹⁰ and R ¹¹ each independently represent fluorine or methyl, and * represents a bonding position; ^R9 represents hydrogen, fluorine, an alkyl group having 1 to 12 carbon atoms, a fluoroalkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms substituted with fluorine, _-OCH2F , _-OCHF2 , or _-OCF3 ; a represents an integer from 0 to 2; b, c, and d each independently represent an integer from 0 to 4; e, f, and g each independently represent an integer from 0 to 3; i and j each independently represent an integer from 0 to 2; * represents a bonding position; when ^R4 , ^R5 , ^R6 , ^R7 , ^R8 , ^R10 , or ^R11 is plural, each independently represents the same or different groups.

In one embodiment of the present invention, in the diamine compound (b1-1) represented by the formula (I), when x is 0, ^X1 is , , , , , , , , , or , wherein R ¹⁴ represents hydrogen or an alkyl group having 1 to 4 carbon atoms; when x is 1, X ¹ is a single bond.

In one embodiment of the present invention, in the diamine compound (b1-1) represented by the formula (I), when x is 0, ^X1 is , , , or .

In one embodiment of the present invention, in the diamine compound (b1-1) represented by the formula (I), R ⁵ , R ⁶ and R ⁷ each independently represent a single bond, , , , , methylene or an alkylene group having 2 to 3 carbon atoms.

In one embodiment of the present invention, in the diamine compound (b1-1) represented by formula (I), when e+f+g<3, f and g are not simultaneously 0; when f≧1, b≧1; when g≧1, c+d≧1.

The present invention provides a polymer (A-1) prepared by reacting a first mixture, wherein the first mixture comprises a tetracarboxylic dianhydride compound (a1) and a diamine compound (b1). The diamine compound (b1) comprises a diamine compound (b1-1) represented by formula (I) as described above.

In one embodiment of the present invention, the diamine compound (b1) further includes a diamine compound (b1-2) represented by formula (II). Formula (II): In formula (II), R ¹⁵ and R ¹⁷ each independently represent , , , , or ; R ¹⁶ represents an alkylene group having 2 to 10 carbon atoms; R ¹⁸ represents a single bond, a methylene group or an ethylene group; Y ¹ represents a monovalent organic group having 17 to 40 carbon atoms and a steroid skeleton.

In one embodiment of the present invention, the diamine compound (b1) further includes a diamine compound (b1-3) represented by formula (III). Formula (III): In formula (III), Y ² each independently represents , , , , , , , or ; ^Y3 each independently represents a single bond, a divalent aliphatic hydrocarbon group having 1 to 20 carbon atoms, a divalent alicyclic hydrocarbon group, or a divalent aromatic hydrocarbon group; Y4 ^each independently represents a single bond, , , , , , , , , or , wherein m represents an integer from 1 to 5; Y ⁵ each independently represents a nitrogen-containing aromatic heterocyclic group; k represents an integer from 1 to 4.

In one embodiment of the present invention, the diamine compound (b1-1) represented by formula (I) is used in an amount of 50 to 100 parts by mole based on 100 parts by mole of the diamine compound (b1).

In one embodiment of the present invention, based on 100 parts by mole of the diamine compound (b1), the diamine compound (b1-2) represented by formula (II) is used in an amount of 5 to 30 parts by mole.

In one embodiment of the present invention, based on 100 parts by mole of the diamine compound (b1), the diamine compound (b1-3) represented by formula (III) is used in an amount of 1 to 20 parts by mole.

The present invention also provides a liquid crystal alignment agent comprising the above polymer (A-1) and a solvent (B).

In one embodiment of the present invention, the liquid crystal alignment agent further comprises a polymer (A-2). The polymer (A-2) is prepared by reacting a second mixture. The second mixture comprises a tetracarboxylic dianhydride compound (a2) and a diamine compound (b2).

In one embodiment of the present invention, based on 100 parts by weight of the polymer (A-1), the amount of the solvent (B) is 1000 parts by weight to 3500 parts by weight.

In one embodiment of the present invention, based on 100 parts by weight of the total amount of the polymer (A-1) and the polymer (A-2), the amount of the polymer (A-1) is 30 parts by weight to 95 parts by weight.

In one embodiment of the present invention, based on the total usage of the polymer (A-1) and the polymer (A-2) being 100 parts by weight, the usage of the solvent (B) is 1000 parts by weight to 3500 parts by weight.

The present invention further provides a liquid crystal alignment film, which is formed by the above-mentioned liquid crystal alignment agent.

The present invention also provides a liquid crystal display element, which includes the above-mentioned liquid crystal alignment film.

Based on the above, when the diamine compound with a specific structure is applied to form a polymer, a liquid crystal alignment agent and a liquid crystal display element, the liquid crystal display element made using the liquid crystal alignment agent can have good electric field memory effect and environmental resistance, and is thus suitable for liquid crystal alignment films and liquid crystal display elements.

In order to make the above features and advantages of the present invention more clearly understood, embodiments are specifically cited below and described in detail with reference to the accompanying drawings.

> Diamine compounds >

The diamine compound is a diamine compound (b1-1) represented by formula (I). Formula (I)

In formula (I), ^X1 and ^X2 each independently represent a single bond, , , , , , , , , , or , wherein R ¹⁴ represents hydrogen or an alkyl group having 1 to 4 carbon atoms.

In formula (I), x represents 0 or 1. When x is 0, ^X1 preferably represents , , , , , , , , , or ; preferably , , , or , wherein R ¹⁴ represents hydrogen or an alkyl group having a carbon number of 1 to 4. When x is 1, X ¹ preferably represents a single bond.

In formula (I), y represents an integer from 0 to 4; preferably, it represents an integer from 0 to 3; more preferably, it represents an integer from 0 to 2.

In formula (I), ^R1 represents a methylene group or an alkylene group having 2 to 4 carbon atoms; preferably, it represents a methylene group or an alkylene group having 2 to 3 carbon atoms; more preferably, it represents a methylene group.

In formula (I), R ³ represents an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a halogen atom or a cyano group; preferably, it represents an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a fluorine atom or a cyano group.

In formula (I), ^R2 represents an organic group represented by formula (IA) or a monovalent organic group having a steroid skeleton and having 17 to 40 carbon atoms.

Formula (IA)

In formula (IA), R ⁴ represents fluorine or methyl.

In formula (IA), R ⁵ , R ⁶ and R ⁷ each independently represent a single bond, -O-, , , , , , methylene or alkylene with 2 to 3 carbon atoms; preferably, each independently represents a single bond, -O-, , , , methylene or an alkylene group having 2 to 3 carbon atoms.

In formula (IA), R ⁸ represents or , wherein R ¹⁰ and R ¹¹ each independently represent fluorine or methyl; * represents a bonding position; i and j each independently represent an integer from 0 to 2.

In formula (I-A), a represents an integer from 0 to 2; b, c and d each independently represent an integer from 0 to 4, preferably each independently represent an integer from 0 to 2; e, f and g each independently represent an integer from 0 to 3, preferably each independently represent an integer from 0 to 2. When e+f+g<3, f and g cannot be 0 at the same time. When f≧1, b≧1. When g≧1, c+d≧1.

In formula (I-A), * represents a bonding position.

In formula (IA), when there are plural R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ¹⁰ or R ¹¹ , each independently represents the same or different group.

Specifically, when f and g are not 0, when a represents 2, each of the plurality of R ^4s may represent the same or different groups; when b, c and d each independently represent an integer of 2 to 4, each of the plurality of R ^5s may represent the same or different groups, each of the plurality of R ^6s may represent the same or different groups, and each of the plurality of R ^7s may represent the same or different groups; when e represents 2 or 3, each of the plurality of R ^8s may represent the same or different groups. In addition, when i represents 2, each of the plurality of R ^10s may represent the same or different groups. When j represents 2, each of the plurality of R ^11s may represent the same or different groups.

In formula (IA), R ⁹ represents hydrogen, fluorine, alkyl having 1 to 12 carbon atoms, fluoroalkyl having 1 to 12 carbon atoms, alkoxy having 1 to 12 carbon atoms, alkoxy having 1 to 12 carbon atoms substituted with fluorine, -OCH ₂ F, -OCHF ₂ , or -OCF ₃ .

Specific examples of the organic group represented by formula (IA) include at least one of the organic groups represented by formula (IA-1) to formula (IA-9). Formula (IA-1) Formula (IA-2) Formula (IA-3) Formula (IA-4) Formula (IA-5) Formula (IA-6) Formula (IA-7) Formula (IA-8) Formula (IA-9)

In formula (IA-1) to formula (IA-9), the group represented by R ⁹ is the same as the group represented by R ⁹ in formula (IA), and will not be described separately here.

The steroid skeleton in the monovalent organic group having a steroid skeleton and having 17 to 40 carbon atoms refers to a cyclopentano-perhydro phenanthrene skeleton or a skeleton in which one or more of the carbon-carbon bonds contained therein are changed to double bonds. Examples of the monovalent organic group having such a steroid skeleton include a group represented by the following formula (IBa), formula (IBb), formula (IBc) or formula (IBd), wherein * indicates a bonding position. Formula (IBa) Formula (IBb) Formula (IBc) Formula (IBd)

In Formula (IBa), Formula (IBb), Formula (IBc) and Formula (IBd), A and ^I each independently represent a group represented by any one of the following structural formulas, wherein * represents a bonding position.

Specific examples of the monovalent organic group having a steroid skeleton and having 17 to 40 carbon atoms include organic groups represented by formula (IB-1), formula (IB-2), formula (IB-3) or formula (IB-4), wherein * represents a bonding position.

Specific examples of the diamine compound (b1-1) represented by formula (I) preferably include compounds represented by formula (I-1) to formula (I-9), and more preferably include compounds represented by formula (I-1) to formula (I-3), formula (I-6), formula (I-7), and formula (I-9). Formula (I-1) Formula (I-2) Formula (I-3) Formula (I-4) Formula (I-5) Formula (I-6) Formula (I-7) Formula (I-8) Formula (I-9)

When the polymer (A-1) in the following liquid crystal alignment agent does not use the diamine compound (b1-1), the liquid crystal alignment film and liquid crystal display element formed by the liquid crystal alignment agent have problems of electric field memory effect and poor environmental resistance. > Liquid Crystal Alignment Agent >

The present invention provides a liquid crystal alignment agent, including a polymer (A-1) and a solvent (B). In other embodiments, the liquid crystal alignment agent may further include a polymer (A-2). In addition, if necessary, the liquid crystal alignment agent may further include an additive (C). The following will describe in detail the various components of the liquid crystal alignment agent used in the present invention. Polymer (A-1)

The polymer (A-1) includes a polyamic acid polymer, a polyimide polymer, a polyimide-based block copolymer or a combination of the above polymers, wherein the polyimide-based block copolymer includes a polyamic acid block copolymer, a polyimide block copolymer, a polyamic acid-polyimide block copolymer or a combination of the above copolymers.

The polymer (A-1) is prepared by reacting a first mixture comprising a tetracarboxylic dianhydride compound (a1) and a diamine compound (b1). The tetracarboxylic dianhydride compound (a1), the diamine compound (b1) and the method for preparing the polymer (A-1) are described in detail below. Tetracarboxylic dianhydride compound (a1)

The tetracarboxylic dianhydride compound (a1) includes tetracarboxylic dianhydride compounds such as aliphatic tetracarboxylic dianhydride compounds, alicyclic tetracarboxylic dianhydride compounds, aromatic tetracarboxylic dianhydride compounds, or tetracarboxylic dianhydride compounds represented by the following formula (1-1) to formula (1-6).

Specific examples of the aliphatic tetracarboxylic dianhydride compound include aliphatic tetracarboxylic dianhydride such as ethanetetracarboxylic dianhydride or butanetetracarboxylic dianhydride. However, the present invention is not limited thereto, and the aliphatic tetracarboxylic dianhydride compound may further include other suitable aliphatic tetracarboxylic dianhydride compounds.

Specific examples of the alicyclic tetracarboxylic dianhydride compounds include 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dichloro-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3 The present invention can be used to prepare alicyclic tetracarboxylic acid dianhydride compounds such as 4-cyclopentane tetracarboxylic acid dianhydride, 1,2,4,5-cyclohexane tetracarboxylic acid dianhydride, 3,3',4,4'-dicyclohexyl tetracarboxylic acid dianhydride, cis-3,7-dibutylcycloheptyl-1,5-diene-1,2,5,6-tetracarboxylic acid dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride or dicyclo[2.2.2]-oct-7-ene-2,3,5,6-tetracarboxylic acid dianhydride. However, the present invention is not limited thereto, and the alicyclic tetracarboxylic acid dianhydride compound can further include other suitable alicyclic tetracarboxylic acid dianhydride compounds.

Specific examples of the aromatic tetracarboxylic dianhydride compounds include 3,4-dicarboxy-1,2,3,4-tetrahydronaphthalene-1-succinic dianhydride, benzene tetracarboxylic dianhydride, 2,2',3,3'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-biphenyl tetracarboxylic dianhydride, 1,4,5,8-naphthalene tetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 3,3'-4,4'-diphenylethane tetracarboxylic dianhydride, 3,3 ',4,4'-dimethyldiphenylsilane tetracarboxylic dianhydride, 3,3',4,4'-tetraphenylsilane tetracarboxylic dianhydride, 1,2,3,4-furan tetracarboxylic dianhydride, 2,3,3',4'-diphenyl ether tetracarboxylic dianhydride, 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenyl sulfide dianhydride, 2,3,3',4'-diphenyl sulfide tetracarboxylic dianhydride, 3,3',4,4'-diphenyl sulfide tetracarboxylic dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenyl sulfide (3,4-dicarboxyphenoxy)diphenylsulfone dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenylpropane dianhydride, 3,3',4,4'-perfluoroisopropylidene diphthalic acid dianhydride, 2,2',3,3'-diphenyltetracarboxylic acid dianhydride, 2,3,3',4'-diphenyltetracarboxylic acid dianhydride, 3,3',4,4'-diphenyltetracarboxylic acid dianhydride, bis(phthalic acid)phenylphosphine oxide dianhydride, p-phenylene-bis(triphenylphthalic acid) dianhydride, m-phenylene-bis(triphenylphthalic acid) phthalic acid) dianhydride, bis(triphenylphthalic acid)-4,4'-diphenyl ether dianhydride, bis(triphenylphthalic acid)-4,4'-diphenylmethane dianhydride, ethylene glycol-bis(dehydrated trimellitate), propylene glycol-bis(dehydrated trimellitate), 1,4-butanediol-bis(dehydrated trimellitate), 1,6-hexanediol-bis(dehydrated trimellitate), 1,8-octanediol-bis(dehydrated trimellitate), 2,2-bis(4-hydroxyphenyl)propane-bis(dehydrated trimellitate), 2, 3,4,5-Tetrahydrofurantetracarboxylic dianhydride, 1,3,3a,4,5,9b-Hexahydro-5-(tetrahydro-2,5-dioxofuran-3-yl)naphtho[1,2-c]furan-1,3-dione, 1,3,3a,4,5,9b-Hexahydro-5-(tetrahydro-2,5-dioxofuran-3-yl)naphtho[1,2-c]furan-1,3-dione, 3,3a,4,5,9b-hexahydro-5-methyl-5-(tetrahydro-2,5-dioxy-3-furanyl)-naphtho[1,2-c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-5-ethyl-5-(tetrahydro-2,5-dioxy-3-furanyl)-naphtho[1,2-c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-7-methyl-5-(tetrahydro-2,5-dioxy-3-furanyl)-naphtho[1,2-c]-furan-1,3-dione 1,3-dione, 1,3,3a,4,5,9b-hexahydro-7-ethyl-5-(tetrahydro-2,5-dioxo-3-furyl)-naphtho[1,2-c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-8-methyl-5-(tetrahydro-2,5-dioxo-3-furyl)-naphtho[1,2-c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-7-ethyl-5-(tetrahydro-2,5-dioxo-3-furyl)-naphtho[1,2-c]-furan-1,3-dione, The aromatic tetracarboxylic acid dianhydride compounds include 1,3-dione, 1,3,3a,4,5,9b-hexahydro-5,8-dimethyl-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-c]-furan-1,3-dione, or 5-(2,5-dioxo-tetrahydrofuranyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic acid dianhydride. However, the present invention is not limited thereto, and the aromatic tetracarboxylic acid dianhydride compounds may further include other suitable aromatic tetracarboxylic acid dianhydride compounds.

The tetracarboxylic dianhydride compounds represented by Formula (1-1) to Formula (1-6) are shown below. Formula (1-1) Formula (1-2) Formula (1-3) Formula (1-4) Formula (1-5) In formula (1-5), ^A1 represents a divalent group containing an aromatic ring; r represents 1 or 2; ^A2 and ^A3 each independently represent hydrogen or an alkyl group. Formula (1-6) In formula (1-6), ^A4 represents a divalent group containing an aromatic ring; ^A5 and ^A6 may each independently represent hydrogen or an alkyl group.

Specific examples of the tetracarboxylic dianhydride compound (a1) represented by the formula (1-5) include tetracarboxylic dianhydride compounds represented by the formula (1-5-1) to the formula (1-5-3). Formula (1-5-1) Formula (1-5-2) Formula (1-5-3)

Specific examples of the tetracarboxylic dianhydride compound (a1) represented by the formula (1-6) include tetracarboxylic dianhydride compounds represented by the formula (1-6-1). Formula (1-6-1)

The above-mentioned tetracarboxylic dianhydride compound (a1) may be used alone or in combination of two or more.

Specific examples of the tetracarboxylic dianhydride compound (a1) preferably include 1,2,3,4-cyclobutane tetracarboxylic acid dianhydride, 1,2,3,4-cyclopentane tetracarboxylic acid dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 1,2,4,5-cyclohexane tetracarboxylic acid dianhydride, 3,4-dicarboxy-1,2,3,4-tetrahydronaphthalene-1-succinic acid dianhydride, pyromellitic acid dianhydride, dianhydride), 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-biphenyl tetracarboxylic dianhydride or a combination thereof, more preferably 1,2,3,4-cyclobutane tetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentyl acetic dianhydride, benzene tetracarboxylic dianhydride or a combination thereof. Diamine compound (b1)

The diamine compound (b1) includes at least one diamine compound (b1-1) represented by formula (I). In addition, the diamine compound (b1) may further include at least one of a diamine compound (b1-2) represented by formula (II) and a diamine compound (b1-3) represented by formula (III). Furthermore, the diamine compound (b1) may also include other diamine compounds (b1-4). The diamine compound (b1-1), the diamine compound (b1-2), the diamine compound (b1-3) and other diamine compounds (b1-4) are described in detail below. Diamine compound (b1-1)

The diamine compound (b1-1) has been described in the above-mentioned "Diamine Compounds" and will not be described again here. When the polymer (A-1) in the liquid crystal alignment agent does not use the diamine compound (b1-1), the liquid crystal alignment film and liquid crystal display element formed by the liquid crystal alignment agent have problems of electric field memory effect and poor environmental resistance.

Based on 100 mol parts of the diamine compound (b1), the diamine compound (b1-1) represented by formula (I ) may be used in an amount of 50 mol parts to 100 mol parts, preferably 55 mol parts to 100 mol parts, and more preferably 65 mol parts to 100 mol parts.

The diamine compound (b1-2) is a diamine compound represented by formula (II). Formula (II)

In formula (II), R ¹⁵ and R ¹⁷ each independently represent an ether group, a thioether group, a thioester group or an ester group. Specifically, R ¹⁵ and R ¹⁷ each independently represent , , , , or .

In formula (II), R ¹⁶ represents an alkylene group having 2 to 10 carbon atoms, preferably an alkylene group having 2 to 4 carbon atoms.

In formula (II), R ¹⁸ represents a single bond, a methylene group or an ethylene group; preferably, it represents a single bond or a methylene group.

In formula (II), ^Y1 represents a monovalent organic group having a steroid skeleton and having 17 to 40 carbon atoms. The steroid skeleton is the same as the steroid skeleton represented by ^R2 in formula (I), and will not be described in detail herein.

Specific examples of the diamine compound (b1-2) include diamine compounds represented by formula (II-1) to formula (II-29), preferably at least one of the diamine compounds represented by formula (II-10), formula (II-18), formula (II-24), formula (II-22), and formula (II-26). Formula (II-1) Formula (II-2) Formula (II-3) Formula (II-4) Formula (II-5) Formula (II-6) Formula (II-7) Formula (II-8) Formula (II-9) Formula (II-10) Formula (II-11) Formula (II-12) Formula (II-13) Formula (II-14) Formula (II-15) Formula (II-16) Formula (II-17) Formula (II-18) Formula (II-19) Formula (II-20) Formula (II-21) Formula (II-22) Formula (II-23) Formula (II-24) Formula (II-25) Formula (II-26) Formula (II-27) Formula (II-28) Formula (II-29)

The diamine compound (b1-2) represented by formula (II) can be synthesized by a known organic synthesis method. For example, the compound represented by formula (II-1), formula (II-2), formula (II-7) or formula (II-8) is synthesized by reacting anhydrous succinic acid with cholesterol or cholestanol, respectively, and then forming an acyl chloride with thionyl chloride, for example, and reacting dinitrophenol with the acyl chloride in the presence of a base having a greater equivalent than the acyl chloride, and then performing a reduction reaction using an appropriate reducing agent such as tin chloride to complete the above synthesis.

The synthesis of the compound represented by formula (II-3), formula (II-4), formula (II-9) or formula (II-10) can be accomplished by subjecting anhydrous succinic acid to an addition reaction with cholesterol or cholesteranol, respectively, and then subjecting the adduct to an esterification reaction with dinitrobenzoyl chloride in the presence of potassium carbonate, followed by a reduction reaction using an appropriate reducing agent such as tin chloride to complete the above synthesis.

The compound represented by formula (II-5) or formula (II-11) can be synthesized by tosylation of cholesterol or cholestanol with tosyl chloride, to obtain tosylated cholesterol or tosylated cholestanol, and then reacting butanediol with an excess of dinitrobenzyl chloride in the presence of an alkali to obtain dinitrobenzylbutanediol monoester, and the tosylated cholestanol are heated in a suitable organic solvent to form an ether group, and then a reduction reaction is carried out using a suitable reducing agent such as tin chloride to complete the above synthesis.

The synthesis of the compound represented by formula (II-6) or formula (II-12) can be carried out by subjecting anhydrous succinic acid to an addition reaction with cholesterol or cholesterol stanol, respectively, reducing the carbonyl group of the aforementioned adduct to a methylene group with lithium aluminum hydride, subjecting the aforementioned reduced product to an esterification reaction with 2,4-dinitrochlorobenzene in the presence of a base such as potassium tert-butoxide, and then subjecting the reduced product to a reduction reaction using an appropriate reducing agent such as tin chloride; or subjecting the reduced product to an esterification reaction with 2,4-dinitrochlorobenzene in the presence of a base such as potassium tert-butoxide. In the presence of a potassium alkoxide base, 2,4-dinitrochlorobenzene is reacted with an excess of butanediol to obtain 1-(4-hydroxybutoxy)-2,4-dinitrobenzene, and the tosylated cholesterol or tosylated cholesterol stanol prepared by the above method are heated in a suitable organic solvent to form an ether group, and then a suitable reducing agent such as tin chloride is used to carry out a reduction reaction to complete the above synthesis.

The compound represented by formula (II-13) can be synthesized by reacting 2,4-dinitrochlorobenzene with an excess of ethylene glycol in the presence of a base such as potassium tert-butoxide to obtain 1-(4-hydroxyethoxy)-2,4-dinitro benzene, and tosylated cholestanol prepared as described above, heating them in a suitable organic solvent to form an ether group, and then using a suitable reducing agent such as tin chloride to carry out a reduction reaction to complete the above synthesis.

The compound represented by formula (II-14), formula (II-15) or formula (II-16) can be synthesized using lanosterol, lumisterol or ergosterol as a starting material, respectively, and according to the synthesis method of formula (II-6).

The compound represented by formula (II-17) or formula (II-18) can be synthesized by mesylation of cholesterol or cholesteranol with methanesulfonyl chloride, followed by substitution reaction with excess ethylene glycol to synthesize a monoether compound, and then reacting the monoether compound with 3,5-dinitrobenzoyl chloride in the presence of alkali to synthesize a dinitro compound, followed by reduction reaction using a suitable reducing agent such as palladium carbon to complete the above synthesis.

The synthesis of the compound represented by formula (II-19) or formula (II-20) can be carried out by using potassium hydroxide to form an alkoxide from cholestanol or cholesterol, respectively, and then reacting with an excess of dibromopropane to form an ether group to obtain an intermediate. Subsequently, in the presence of potassium carbonate, the intermediate is reacted with 3,5-dinitrobenzoic acid to synthesize a dinitro compound, and then a suitable reducing agent such as palladium carbide is used to carry out a reduction reaction to complete the above synthesis.

The compound represented by formula (II-21) or formula (II-22) can be synthesized by subjecting anhydrous succinic acid to an addition reaction with cholesterol or cholesteranol, respectively, and then reacting the adduct with 3,5-(N,N-diallyl) aminophenol in the presence of N,N-dicyclohexylcarbodiimide, and then removing the allyl group with 1,3-dimethylbarbituric acid and tetrakistriphenyl phosphinepalladium to obtain the compound.

The synthesis of the compound represented by formula (II-23) or formula (II-24) can be carried out by subjecting anhydrous succinic acid to an addition reaction with cholesterol or cholesteranol, respectively, and then using a borane-tetrahydrofuran complex (Borane-oxolane complex) to reduce the carbonyl group to an alcohol as an intermediate; in the presence of an alkali, the aforementioned intermediate is reacted with 3,5-dinitrobenzoyl chloride to synthesize a dinitro compound, and then a reduction reaction is carried out using a suitable reducing agent such as palladium carbide to complete the above synthesis.

The compound represented by formula (II-25) or formula (II-26) can be synthesized by subjecting anhydrous glutaric acid-substituted succinic acid to an addition reaction with cholesterol or cholesteranol, respectively, and then synthesizing according to the synthesis method of formula (II-4) or formula (II-10).

The synthesis of the compound represented by formula (II-27), formula (II-28) or formula (II-29) can be carried out by hydrogenating lanosterol, ergosterol or ergosterol using a suitable hydrogenation catalyst as the starting material and synthesizing it according to the synthesis method of formula (II-14), formula (II-15) or formula (II-16).

When the diamine compound (b1) in the polymer (A-1) in the liquid crystal alignment agent includes the diamine compound (b1-2), the liquid crystal alignment film and the liquid crystal display element formed by the liquid crystal alignment agent can have a better electric field memory effect.

Based on 100 mol parts of the diamine compound (b1), the diamine compound (b1-2) represented by formula ( II) may be used in an amount of 5 mol parts to 30 mol parts, preferably 7 mol parts to 27 mol parts, and more preferably 10 mol parts to 25 mol parts.

The diamine compound (b1-3) is a diamine compound (b1-3) represented by formula (III). Formula (III): In formula (III), Y ² each independently represents , , , , , , , or ; Y ³ each independently represents a single bond, a divalent aliphatic hydrocarbon group having 1 to 20 carbon atoms, a divalent alicyclic hydrocarbon group, or a divalent aromatic hydrocarbon group; Y ⁴ each independently represents a single bond, , , , , , , , , or , wherein m represents an integer from 1 to 5; Y ⁵ each independently represents a nitrogen-containing aromatic heterocyclic group; and k represents an integer from 1 to 4.

In detail, the bonding positions of the two amine groups (-NH ₂ ) in formula (III) are not particularly limited. Specifically, the two amine groups on the benzene ring are at the 2,3 position, 2,4 position, 2,5 position, 2,6 position, 3,4 position or 3,5 position, etc., relative to the bonding group (Y ² ) of the side chain. From the viewpoint of reactivity when synthesizing polyamine, the bonding positions of the two amine groups are preferably at the 2,4 position, 2,5 position or 3,5 position. And from the perspective of ease of synthesizing a diamine compound, the bonding positions of the two amine groups are more preferably at the 2,4 position or 2,5 position.

In formula (III), Y ² each independently represents , , , , , , , or In terms of ease of synthesizing the diamine compound, Y ² is preferably independently represented by , , , , , or .

In formula (III), Y ³ each independently represents a single bond, a divalent aliphatic alkyl group having 1 to 20 carbon atoms, a divalent alicyclic alkyl group, or a divalent aromatic alkyl group. The divalent aliphatic alkyl group having 1 to 20 carbon atoms may be linear or branched, and may have an unsaturated bond, and is preferably a divalent aliphatic alkyl group having 1 to 10 carbon atoms. Specific examples of the alicyclic ring in the divalent alicyclic hydrocarbon group include a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, a cyclooctane ring, a cyclononane ring, a cyclodecane ring, a cycloundecane ring, a cyclododecane ring, a cyclotridecane ring, a cyclotetradecane ring, a cyclopentadecane ring, a cyclohexadecane ring, a cycloheptadecane ring, a cyclooctadecane ring, a cyclononadecane ring, a cycloeicosane ring, a tricycloeicosane ring, a tricyclodocosane ring, a bicycloheptane ring, a cyclotetradecane ring, a cyclopentadecane ring, a cyclohexadecane ring, a cycloheptadecane ring, a cyclooctadecane ring, a cyclononadecane ring, a cycloeicosane ring, a tricycloeicosane ring, a tricyclodocosane ring, a bicycloheptane ring, a ring), decahydronaphthalene ring, norbornene ring, or adamantane ring.

Specific examples of the aromatic ring in the divalent aromatic hydrocarbon group include a benzene ring, a naphthyl ring, a tetrahydronaphthyl ring, an azulene ring, an indene ring, a fluorene ring, an anthracene ring, a phenanthrene ring, or a phenalene ring.

Specifically, in formula (III), Y ³ preferably independently represents a single bond, a methylene group, a straight chain or branched alkylene group having 2 to 10 carbon atoms, a straight chain or branched alkenylene group having 2 to 10 carbon atoms, a straight chain or branched alkynylene group having 2 to 10 carbon atoms, a divalent alicyclic hydrocarbon group, or a divalent aromatic hydrocarbon group, wherein the alicyclic ring in the divalent alicyclic hydrocarbon group is a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, a norbornene ring, or an adamantane ring, and the aromatic ring in the divalent aromatic hydrocarbon group is a benzene ring, a naphthyl ring, a tetrahydronaphthyl ring, a fluorene ring, or anthracene ring. ^Y3 is more preferably each independently a single bond, a methylene group, a straight or branched alkylene group having 2 to 10 carbon atoms, a straight or branched alkenylene group having 2 to 10 carbon atoms, a divalent alicyclic hydrocarbon group, or a divalent aromatic hydrocarbon group, wherein the alicyclic ring in the divalent alicyclic hydrocarbon group is a cyclohexane ring, a norbornene ring, or an adamantane ring, and the aromatic ring in the divalent aromatic hydrocarbon group is a benzene ring, a naphthalene ring, a fluorene ring, or an anthracene ring. ^Y3 is even more preferably each independently a single bond, a methylene group, a straight or branched alkylene group having 2 to 10 carbon atoms, a cyclohexylene group, a phenylene group, or a naphthylene group. ^Y3 is particularly preferably each independently a single bond, a methylene group, a straight or branched alkylene group having 2 to 5 carbon atoms, or a phenylene group.

In formula (III), Y ⁴ each independently represents a single bond, , , , , , , , , or , wherein m represents an integer from 1 to 5. Y ⁴ preferably each independently represents a single key, , , , , or , where m represents an integer from 1 to 5.

In formula (III), Y ⁵ each independently represents a nitrogen-containing aromatic heterocyclic group. Specifically, the nitrogen-containing aromatic heterocyclic group is a nitrogen-containing aromatic heterocyclic group having at least one structure selected from the group consisting of formula (III-A), formula (III-B) and formula (III-C). In formula (III-C), R ¹⁹ represents a linear or branched alkyl group having 1 to 5 carbon atoms.

Specific examples of the nitrogen-containing aromatic heterocyclic ring in ^Y5 include a pyrrole ring, an imidazole ring, an oxazole ring, a thiazole ring, a pyrazole ring, a pyridine ring, a pyrimidine ring, a quinoline ring, a pyrazoline ring, an isoquinoline ring, a carbazole ring, a purine ring, a thiadiazole ring, a pyridazine ring, a pyrazoline ring, a triazine ring, a pyrazolidine ring, a triazole ring, a pyrazine ring, The ring is preferably a pyrrolyl group, an imidazolyl group, a pyrazolyl group, a pyridyl group, a pyrimidyl group, a oxazolyl group, a triazinyl group, a triazolyl group, a pyrazinyl group or a benzimidazolyl group. ^{The ring} is preferably a pyrrolyl group, an imidazolyl group, a pyrazolyl group, a pyridyl group or a pyrimidyl group.

In addition, ^Y4 is preferably bonded to a substituent that is not adjacent to ^Y5 in the formula (III-A), formula (III-B) and formula (III-C).

In formula (III), k represents an integer of 1 to 4. From the viewpoint of reactivity with tetracarboxylic dianhydride compounds, k is preferably an integer of 1 to 3. When k represents an integer of 2 to 4, each of the plurality of Y ² , Y ³ , Y ⁴ , and Y ⁵ in the plurality of "-Y ² -Y ³ -Y ⁴ -Y ⁵ " may represent the same or different groups.

In formula (III), the preferred combination of Y ² , Y ³ , Y ⁴ , Y ⁵ and k is: Y ² is , , , , , or ; ^Y3 is a methylene group, a linear or branched alkylene group having 2 to 10 carbon atoms, a linear or branched alkenylene group having 2 to 10 carbon atoms, a divalent alicyclic hydrocarbon group, or a divalent aromatic hydrocarbon group, wherein the alicyclic ring in the divalent alicyclic hydrocarbon group is a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, a norbornene ring, or an adamantane ring, and the aromatic ring in the divalent aromatic hydrocarbon group is a benzene ring, a naphthalene ring, a tetrahydronaphthalene ring, a fluorene ring, or an anthracene ring; ^Y4 is a single bond, , , , , , or (m is an integer from 1 to 5); the nitrogen-containing aromatic heterocyclic ring in Y ⁵ is a pyrrole ring, an imidazole ring, an oxazole ring, a thiazole ring, a pyrazole ring, a pyridine ring, a pyrimidine ring, a quinoline ring, a pyrazoline ring, an isoquinoline ring, a carbazole ring, a purine ring, a thiadiazole ring, a oxazine ring, a pyrazoline ring, a triazine ring, a pyrazolinane ring, a triazole ring, a pyrazine ring, a benzimidazole ring, a phenanthroline ring, an indole ring, a quinoxaline ring, a benzothiazole ring, a phenothiazine ring, an oxadiazole ring or an acridine ring; and k is 1 or 2.

In formula (III), a more preferred combination of Y ² , Y ³ , Y ⁴ , Y ⁵ and k is: Y ² is , , , , or ; ^Y3 is methylene, a linear or branched alkylene group having 2 to 10 carbon atoms, a linear or branched alkenylene group having 2 to 10 carbon atoms, a divalent alicyclic hydrocarbon group, or a divalent aromatic hydrocarbon group, wherein the alicyclic ring in the divalent alicyclic hydrocarbon group is a cyclohexane ring, a norbornene ring, or an adamantane ring, and the aromatic ring in the divalent aromatic hydrocarbon group is a benzene ring, a naphthalene ring, a fluorene ring, or an anthracene ring; ^Y4 is a single bond, , , , , , or (m is an integer from 1 to 5); Y ⁵ is pyrrolyl, imidazolyl, pyrazolyl, pyridinyl, pyrimidinyl, pyrazolinyl, carbazolyl, oxazinyl, pyrazolinyl, triazinyl, pyrazolinalkyl, triazolyl, pyrazinyl or benzimidazolyl; and k is 1 or 2.

In formula (III), a more preferred combination of Y ² , Y ³ , Y ⁴ , Y ⁵ and k is: Y ² is , , , , ,or ; Y ³ is methylene, a linear or branched alkylene or phenylene having 2 to 5 carbon atoms; Y ⁴ is a single bond, , , , , ,or (m is an integer from 1 to 5); Y ⁵ is pyrrolyl, imidazolyl, pyrazolyl, pyridinyl or pyrimidinyl; and k is 1, 2 or 3.

Specific examples of the diamine compound (b1-3) include diamine compounds of combinations of Y ² , Y ³ , Y ⁴ , Y ⁵ and k described in Tables I to VIII.

Table I Diamine compound (b1-3) NO. Y ² Y ³ Y ⁴ Y ⁵ 1 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyrrolyl 2 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Imidazolyl 3 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyrazolyl 4 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyridyl 5 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyrimidine 6 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyrrolyl 7 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Imidazolyl 8 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyrazolyl 9 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyridyl 10 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyrimidine 11 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyrrolyl 12 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Imidazolyl 13 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyrazolyl 14 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyridyl 15 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyrimidine 16 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyrrolyl 17 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Imidazolyl 18 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyrazolyl 19 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyridyl 20 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyrimidine

Table II Diamine compound (b1-3) NO. Y ² Y ³ Y ⁴ Y ⁵ twenty one Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyrrolyl twenty two Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Imidazolyl twenty three Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyrazolyl twenty four Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyridyl 25 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyrimidine 26 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyrrolyl 27 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Imidazolyl 28 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyrazolyl 29 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyridyl 30 Methylene, straight or branched alkylene with 2 to 5 carbon atoms Single button Pyrimidine

Table III Diamine compound (b1-3) NO. Y ² Y ³ Y ⁴ Y ⁵ 31 Phenyl Pyrrolyl 32 Phenyl Imidazolyl 33 Phenyl Pyrazolyl 34 Phenyl Pyridyl 35 Phenyl Pyrimidine 36 Phenyl Pyrrolyl 37 Phenyl Imidazolyl 38 Phenyl Pyrazolyl 39 Phenyl Pyridyl 40 Phenyl Pyrimidine 41 Phenyl Pyrrolyl 42 Phenyl Imidazolyl 43 Phenyl Pyrazolyl 44 Phenyl Pyridyl 45 Phenyl Pyrimidine 46 Phenyl Pyrrolyl 47 Phenyl Imidazolyl 48 Phenyl Pyrazolyl 49 Phenyl Pyridyl 50 Phenyl Pyrimidine 51 Phenyl (m: 1~5) Pyrrolyl 52 Phenyl (m: 1~5) Imidazolyl 53 Phenyl (m: 1~5) Pyrazolyl 54 Phenyl (m: 1~5) Pyridyl 55 Phenyl Pyrrolyl 56 Phenyl Imidazolyl 57 Phenyl Pyrazolyl 58 Phenyl Pyridyl 59 Phenyl Pyrimidine 60 Phenyl Pyrrolyl

Table IV Diamine compound (b1-3) NO. Y ² Y ³ Y ⁴ Y ⁵ 61 Phenyl Imidazolyl 62 Phenyl Pyrazolyl 63 Phenyl Pyridyl 64 Phenyl Pyrimidine 65 Phenyl Pyrrolyl 66 Phenyl Imidazolyl 67 Phenyl Pyrazolyl 68 Phenyl Pyridyl 69 Phenyl Pyrimidine 70 Phenyl Pyrrolyl 71 Phenyl Imidazolyl 72 Phenyl Pyrazolyl 73 Phenyl Pyridyl 74 Phenyl Pyrimidine 75 Phenyl (m: 1~5) Pyrrolyl 76 Phenyl (m: 1~5) Imidazolyl 77 Phenyl (m: 1~5) Pyrazolyl 78 Phenyl (m: 1~5) Pyridyl

Table V Diamine compound (b1-3) NO. Y ² Y ³ Y ⁴ Y ⁵ 79 Phenyl Pyrrolyl 80 Phenyl Imidazolyl 81 Phenyl Pyrazolyl 82 Phenyl Pyridyl 83 Phenyl Pyrimidine 84 Phenyl Pyrrolyl 85 Phenyl Imidazolyl 86 Phenyl Pyrazolyl 87 Phenyl Pyridyl 88 Phenyl Pyrimidine 89 Phenyl Pyrrolyl 90 Phenyl Imidazolyl 91 Phenyl Pyrazolyl 92 Phenyl Pyridyl 93 Phenyl Pyrimidine 94 Phenyl Pyrrolyl 95 Phenyl Imidazolyl 96 Phenyl Pyrazolyl 97 Phenyl Pyridyl 98 Phenyl Pyrimidine 99 Phenyl (m: 1~5) Pyrrolyl 100 Phenyl (m: 1~5) Imidazolyl 101 Phenyl (m: 1~5) Pyrazolyl 102 Phenyl (m: 1~5) Pyridyl 103 Phenyl Pyrrolyl 104 Phenyl Imidazolyl 105 Phenyl Pyrazolyl 106 Phenyl Pyridyl 107 Phenyl Pyrimidine 108 Phenyl Pyrrolyl 109 Phenyl Imidazolyl 110 Phenyl Pyrazolyl

Table VI Diamine compound (b1-3) NO. Y ² Y ³ Y ⁴ Y ⁵ 111 Phenyl Pyridyl 112 Phenyl Pyrimidine 113 Phenyl Pyrrolyl 114 Phenyl Imidazolyl 115 Phenyl Pyrazolyl 116 Phenyl Pyridyl 117 Phenyl Pyrimidine 118 Phenyl Pyrrolyl 119 Phenyl Imidazolyl 120 Phenyl Pyrazolyl 121 Phenyl Pyridyl 122 Phenyl Pyrimidine 123 Phenyl (m: 1~5) Pyrrolyl 124 Phenyl (m: 1~5) Imidazolyl 125 Phenyl (m: 1~5) Pyrazolyl 126 Phenyl (m: 1~5) Pyridyl

Table VII Diamine compound (b1-3) NO. Y ² Y ³ Y ⁴ Y ⁵ 127 Phenyl Pyrrolyl 128 Phenyl Imidazolyl 129 Phenyl Pyrazolyl 130 Phenyl Pyridyl 131 Phenyl Pyrimidine 132 Phenyl Pyrrolyl 133 Phenyl Imidazolyl 134 Phenyl Pyrazolyl 135 Phenyl Pyridyl 136 Phenyl Pyrimidine 137 Phenyl Pyrrolyl 138 Phenyl Imidazolyl 139 Phenyl Pyrazolyl 140 Phenyl Pyridyl 141 Phenyl Pyrimidine 142 Phenyl Pyrrolyl 143 Phenyl Imidazolyl 144 Phenyl Pyrazolyl 145 Phenyl Pyridyl 146 Phenyl Pyrimidine 147 Phenyl (m: 1~5) Pyrrolyl 148 Phenyl (m: 1~5) Imidazolyl 149 Phenyl (m: 1~5) Pyrazolyl 150 Phenyl (m: 1~5) Pyridyl 151 Phenyl Pyrrolyl 152 Phenyl Imidazolyl 153 Phenyl Pyrazolyl 154 Phenyl Pyridyl 155 Phenyl Pyrimidine

Table VIII Diamine compound (b1-3) NO. Y ² Y ³ Y ⁴ Y ⁵ 156 Phenyl Pyrrolyl 157 Phenyl Imidazolyl 158 Phenyl Pyrazolyl 159 Phenyl Pyridyl 160 Phenyl Pyrimidine 161 Phenyl Pyrrolyl 162 Phenyl Imidazolyl 163 Phenyl Pyrazolyl 164 Phenyl Pyridyl 165 Phenyl Pyrimidine 166 Phenyl Pyrrolyl 167 Phenyl Imidazolyl 168 Phenyl Pyrazolyl 169 Phenyl Pyridyl 170 Phenyl Pyrimidine 171 Phenyl Pyrrolyl 172 Phenyl (m: 1~5) Imidazolyl 173 Phenyl (m: 1~5) Pyrazolyl 174 Phenyl (m: 1~5) Pyridyl

The method for producing the diamine compound (b1-3) of the present invention is not particularly limited, and can be produced, for example, by the following method: first synthesizing a dinitro compound represented by formula (III-D), and then reducing the nitro group to an amino group in the presence of a catalyst, a solvent, and a hydride. Formula (III-D) In formula (III-D), Y ² , Y ³ , Y ⁴ , Y ⁵ and k are synonymous with Y ² , Y ³ , Y ⁴ , Y ⁵ and k in formula (III), and are not further described herein.

Specific examples of the catalyst are not particularly limited but may include palladium-carbon, platinum dioxide, Raney nickel, platinum black, rhodium-alumina, platinum sulfide-carbon, or a combination of the above catalysts. Specific examples of the solvent are not particularly limited but may include ethyl acetate, toluene, tetrahydrofuran, dioxane, alcohols, or a combination of the above solvents. Specific examples of the hydride are not particularly limited but may include hydrogen, hydrazine, hydrogen chloride, or a combination of the above compounds.

The dinitro compound represented by formula (III-D) is synthesized by a method in which ^Y3 and ^Y5 are bonded via ^Y4 ; then ^Y3 is bonded to a benzene ring containing a dinitro group via ^Y2 ; or a benzene ring containing a dinitro group is bonded to ^Y3 via ^Y2 , then ^Y3 is bonded to ^Y5 via ^Y4 .

^Y2 is , , , , , , , or These binding groups can be formed by known organic synthesis methods.

For example, in ^Y2 or In the case of , the dinitro compound represented by formula (III-D) can be obtained by reacting a halogen derivative containing a dinitro group with a hydroxy derivative containing Y ³ , Y ⁴ and Y ⁵ in the presence of a base; or by reacting a hydroxy derivative containing a dinitro group with a halogen substituted derivative containing Y ³ , Y ⁴ and Y ⁵ in the presence of a base.

In ^Y2 In the case of , the dinitro compound represented by formula (III-D) can be obtained by reacting a halogen derivative containing a dinitro group with an amino group-substituted derivative containing Y ³ , Y ⁴ and Y ⁵ in the presence of a base.

In ^Y2 In the case of, the dinitro compound represented by formula (III-D) can be obtained by reacting a hydroxy derivative containing a dinitro group with an acid chloride compound containing Y ³ , Y ⁴ and Y ⁵ in the presence of a base.

In ^Y2 In the case of , the dinitro compound represented by formula (III-D) can be obtained by reacting an acyl chloride compound containing a dinitro group with an amino-substituted compound containing Y ³ , Y ⁴ and Y ⁵ in the presence of a base.

In ^Y2 In the case of , the dinitro compound represented by formula (III-D) can be obtained by reacting an amino-substituted compound with an acyl chloride compound containing a dinitro group containing Y ³ , Y ⁴ and Y ⁵ in the presence of a base.

Specific examples of the halogen derivatives containing a dinitro group and the derivatives containing a dinitro group include 3,5-dinitrochlorobenzene, 2,4-dinitrochlorobenzene, 2,4-dinitrofluorobenzene, 3,5-dinitrobenzoyl chloride, 3,5-dinitrobenzoic acid, 2,4-dinitrobenzoyl chloride, 2,4-dinitrobenzoic acid, 3,5-dinitro benzyl chloride, 2,4-dinitrobenzyl chloride, dinitro group-containing halogen derivatives and dinitro group-containing derivatives may be used alone or in combination in view of the availability of raw materials and reactivity.

Specific examples of the diamine compound (b1-3) preferably include at least one of the diamine compounds represented by formula (III-1) to formula (III-6). Formula (III-1) Formula (III-2) Formula (III-3) Formula (III-4) Formula (III-5) Formula (III-6)

When the diamine compound (b1) in the polymer (A-1) in the liquid crystal alignment agent includes the diamine compound (b1-3), the liquid crystal alignment film and the liquid crystal display element formed by the liquid crystal alignment agent can have better environmental resistance.

Based on 100 mol parts of the diamine compound (b1), the diamine compound (b1-3) represented by formula (III) may be used in an amount of 1 mol to 20 mol parts, preferably 3 mol to 18 mol parts, and more preferably 5 mol to 15 mol parts. Other diamine compounds (b1-4)

Specific examples of other diamine compounds (b1-4) include 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 4,4'-diaminoheptane, 1,3-diamino-2,2-dimethylpropane, 1,6-diamino-2,5-dimethylhexane, 1,7-diamino-2,5-dimethylheptane, 1,7-diamino-4,4- Dimethylheptane, 1,7-diamino-3-methylheptane, 1,9-diamino-5-methylnonane, 2,11-diaminododecane, 1,12-diaminooctadecane, 1,2-bis(3-aminopropoxy)ethane, 4,4'-diaminodicyclohexylmethane, 4,4'-diamino-3,3'-dimethyldicyclohexylamine, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane (1,4-diaminocyclohexane), isophoronediamine, tetrahydrodicyclopentadienediamine, tricyclo[6.2.1.0 ^2,7 ]-undecylenedimethyl diamine, 4,4'-methylenebis(cyclohexylamine), 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylethane, 4,4'-diaminodiphenylsulfone, 4,4'-diaminobenzanilide, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 1,5-diaminonaphthalene, 5-amino-1-(4'-aminophenyl)-1,3, 3-Trimethylhydroindene, 6-amino-1-(4'-aminophenyl)-1,3,3-trimethylhydroindene, hexahydro-4,7-methanedihydroindene dimethylenediamine, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, 4,4'-diaminobenzophenone, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis(4-aminophenyl)hexafluoropropane, 2,2-bis[4-(4-aminophenyl) 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 9,9-bis(4-aminophenyl)-10-hydroanthracene, 9,10-bis(4-aminophenyl)anthracene, 2,7-diaminofluorene, 9,9-bis(4-aminophenyl)fluorene, 4,4'-methylene-bis(2-chloroaniline), 4,4'-( p-phenylene isopropylidene)bisaniline, 4,4'-(m-phenylene isopropylidene)bisaniline, 2,2'-bis[4-(4-amino-2-trifluoromethylphenoxy)phenyl]hexafluoropropane, 4,4'-bis[(4-amino-2-trifluoromethyl)phenoxy]-octafluorobiphenyl, 5-[4-(4-n-pentylcyclohexyl)cyclohexyl]phenylmethylene-1,3-diaminobenzene (5-[4-(4-n-pentylcyclohexyl)cyclohexyl]phenyl methylene-1,3-diaminobenzene), 1,1-bis[4-(4-aminophenoxy)phenyl]-4-(4-ethylphenyl)cyclohexane, or other diamine compounds (b1-4) represented by formula (2-1) to formula (2-25). However, the present invention is not limited thereto, and other diamine compounds (b1-4) may further include other suitable diamine compounds.

Other diamine compounds represented by formula (2-1) to formula (2-25) are shown below.

Formula (2-1) In formula (2-1), B ¹ represents , , , , or ; ^B2 represents a steryl group, a trifluoromethyl group, a fluoro group, an alkyl group having 2 to 30 carbon atoms, or a monovalent group derived from a nitrogen atom-containing cyclic structure such as pyridine, pyrimidine, triazine, piperidine and piperazine.

Specific examples of other diamine compounds represented by formula (2-1) include 2,4-diaminophenyl ethyl formate, 3,5-diaminophenyl ethyl formate, 2,4-diaminophenyl propyl formate, 3,5-diaminophenyl propyl formate, 1-dodecoxy-2,4-diaminobenzene, 1-hexadecoxy-2,4-diaminobenzene, 1-octadecoxy-2,4-diaminobenzene, or other diamine compounds represented by formula (2-1-1) to formula (2-1-4). Formula (2-1-1) Formula (2-1-2) Formula (2-1-3) Formula (2-1-4)

Formula (2-2): In formula (2-2), B ³ represents , , , , or ; ^B4 and ^B5 represent an aliphatic ring extension, an aromatic ring extension or a heterocyclic group; ^B6 represents an alkyl group having 3 to 18 carbon atoms, an alkoxy group having 3 to 18 carbon atoms, a fluoroalkyl group having 1 to 5 carbon atoms, a fluoroalkoxy group having 1 to 5 carbon atoms, a cyano group or a halogen atom.

Specific examples of other diamine compounds represented by formula (2-2) include diamine compounds represented by formula (2-2-1) to formula (2-2-13). Formula (2-2-1) Formula (2-2-2) Formula (2-2-3) Formula (2-2-4) Formula (2-2-5) Formula (2-2-6) Formula (2-2-7) Formula (2-2-8) Formula (2-2-9) Formula (2-2-10) Formula (2-2-11) Formula (2-2-12) Formula (2-2-13) In Formula (2-2-10) to Formula (2-2-13), q represents an integer from 3 to 12.

Formula (2-3) In formula (2-3), ^B7 represents hydrogen, an acyl group having 1 to 5 carbon atoms, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or a halogen; s represents an integer from 1 to 3. When s represents an integer of 2 or 3, multiple ^B7s may be the same or different.

Specific examples of the diamine compound represented by formula (2-3) include (1) when s is 1: p-diaminobenzene, m-diaminobenzene, o-diaminobenzene or 2,5-diaminotoluene, etc.; (2) when s is 2: 4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl (2,2'-dimethyl-4,4'-diaminobiphenyl); diphenyl), 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 2,2'-dichloro-4,4'-diaminobiphenyl, 3,3'-dichloro-4,4'-diaminobiphenyl, 2,2',5,5'-tetrachloro-4,4'-diaminobiphenyl, 2,2'-dichloro-4,4'-diamino-5,5'-dimethoxybiphenyl or 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl; (3) when s is 3: 1,4-bis(4'-aminophenyl)benzene or a combination thereof. Specific examples of the diamine compound represented by formula (2-3) preferably include p-diaminobenzene, 2,2'-dimethyl-4,4'-diaminobiphenyl or a combination thereof.

Formula (2-4) In formula (2-4), t represents an integer from 2 to 12.

Formula (2-5) In formula (2-5), v represents an integer from 1 to 5.

Specific examples of the diamine compound represented by the formula (2-5) include 4,4'-diaminodiphenyl sulfide.

Formula (2-6) In formula (2-6), ^B8 and ^B10 each independently represent a divalent organic group, and ^B9 represents a divalent group derived from a nitrogen atom-containing cyclic structure such as pyridine, pyrimidine, triazine, piperidine and piperazine.

Formula (2-7) In formula (2-7), B ¹¹ , B ¹² , B ¹³ and B ¹⁴ each independently represent a alkyl group having 1 to 12 carbon atoms; w represents an integer of 1 to 3; and z represents an integer of 1 to 20.

Formula (2-8) In formula (2-8), B ¹⁵ represents or a cyclohexylene group; B ¹⁶ represents a methylene group; B ¹⁷ represents a phenylene group or a cyclohexylene group; B ¹⁸ represents a hydrogen group or a heptyl group.

Specific examples of the diamine compound represented by the formula (2-8) include diamine compounds represented by the formula (2-8-1) to the formula (2-8-2). Formula (2-8-1) Formula (2-8-2)

Other diamine compounds represented by formula (2-9) to formula (2-25) are shown below. Formula (2-9) Formula (2-10) Formula (2-11) Formula (2-12) Formula (2-13) Formula (2-14) Formula (2-15) Formula (2-16) Formula (2-17) Formula (2-18) Formula (2-19) Formula (2-20) Formula (2-21) Formula (2-22) Formula (2-23) Formula (2-24) Formula (2-25) In formula (2-17) to formula (2-25), B ¹⁹ represents an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms; and B ²⁰ represents hydrogen, an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms.

Specific examples of other diamine compounds (b1-4) may also include diamine compounds having a chalcone structure such as 3,3’-diaminochalcone, 4,4’-diaminochalcone, 3,4’-diaminochalcone or 3,4-diaminochalcone; 3,3’-diaminostilbene, 4,4’-diaminostilbene, 4,4’-diaminostilbene-2,2’-sulfonic acid; diamine compounds having a stilbene structure, such as 4,4'-bis(4-amino-1-naphthylazo)-2,2'-stilbene sulfonic acid; 1,2-diamino anthraquinone, 1,4-diamino anthraquinone, 1,5-diamino anthraquinone or 1,4-diamino anthraquinone-2,3-dicyano-9,10-anthraquinone; diamine compounds having an anthraquinone structure such as anthraquinone-2,3-dicyano-9,10-anthraquinone; or diamine compounds having a carbazole structure such as 3,6-diaminocarbazole.

Specific examples of other diamine compounds (b1-4) preferably include 1,2-diaminoethane, 4,4'-diaminodicyclohexylmethane, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 5-[4-(4-n-pentylcyclohexyl)cyclohexyl]phenylmethylene-1,3-diaminobenzene, 1,1-bis[4-(4-aminophenoxy)phenyl]-4-(4-ethylphenyl)cyclohexane, 2,4-diaminophenyl ethyl formate, 2,2'-dimethyl-4,4'- Diaminobiphenyl, 4,4'-methylenebis(cyclohexylamine), 1,4-diaminocyclohexane, a diamine compound represented by formula (2-1-1), a diamine compound represented by formula (2-1-2), a diamine compound represented by formula (2-2-1), a diamine compound represented by formula (2-2-11), p-diaminobenzene, m-diaminobenzene, o-diaminobenzene, a diamine compound represented by formula (2-8-1), 3,3'-diaminochalcone or 4,4'-diaminostilbene, etc.

Specific examples of other diamine compounds (b1-4) preferably include p-diaminobenzene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 4,4'-methylenebis(cyclohexylamine), 1,4-diaminocyclohexane, 3,3'-diaminochalcone or a combination thereof.

Based on 100 mol parts of the diamine compound (b1), the amount of the other diamine compounds (b1-4) can be 0 mol parts to 70 mol parts, preferably 0 mol parts to 60 mol parts, and more preferably 0 mol parts to 50 mol parts. Method for preparing polymer (A-1) Method for preparing polyamide polymer

The method for preparing a polyamine polymer is to first dissolve a first mixture in a solvent, wherein the first mixture includes a tetracarboxylic dianhydride compound (a1) and a diamine compound (b1), and perform a polycondensation reaction at a temperature of 0°C to 100°C. After reacting for 1 to 24 hours, the reaction solution is subjected to reduced pressure distillation in an evaporator to obtain a polyamine polymer. Alternatively, the reaction solution is poured into a large amount of an anhydrous solvent to obtain a precipitate. Then, the precipitate is dried by reduced pressure drying to obtain a polyamine polymer. Based on the usage of 100 mol parts of the tetracarboxylic dianhydride compound (a1), the usage of the diamine compound (b1) can be 20 mol parts to 200 mol parts, preferably 30 mol parts to 120 mol parts.

The solvent used in the polymerization reaction may be the same as or different from the solvent in the liquid crystal alignment agent described below, and there is no particular limitation on the solvent used in the polymerization reaction, as long as it can dissolve the reactants and the products. Specific examples of the solvent include (1) aprotic polar solvents, such as N-methyl-2-pyrrolidone (NMP), N,N-dimethylacetamide, N,N-dimethylformamide, dimethyl sulfoxide, γ-butyrolactone, tetramethyl urea or hexamethylphosphoric acid triamide; (2) phenolic solvents, such as m-cresol, xylenol, phenol or halogenated phenols; or combinations of the above solvents. However, the present invention is not limited thereto, and the solvent may further include other suitable solvents. Based on the total usage of the first mixture being 100 parts by weight, the usage of the solvent used in the polycondensation reaction may be 200 parts by weight to 2000 parts by weight, preferably 300 parts by weight to 1800 parts by weight.

In the polycondensation reaction, the solvent may be used together with an appropriate amount of a poor solvent, wherein the poor solvent will not cause the polyamine polymer to precipitate. Specific examples of poor solvents include (1) alcohols, such as methanol, ethanol, isopropanol, cyclohexanol, ethylene glycol, propylene glycol, 1,4-butanediol or triethylene glycol; (2) ketones, such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and other ketones; (3) esters, such as methyl acetate, ethyl acetate, butyl acetate, diethyl oxalate, diethyl malonate or ethylene glycol ethyl ether acetate and other esters; (4) ethers, such as diethyl ether, ethyl acetate, diethyl oxalate, diethyl malonate or ethylene glycol ethyl ether acetate and other esters. (5) halogenated hydrocarbons, such as dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene or o-dichlorobenzene; (6) hydrocarbons, such as tetrahydrofuran, hexane, heptane, octane, benzene, toluene or xylene or a combination of the above-mentioned poor solvents. However, the present invention is not limited thereto, and the poor solvent may further include other suitable solvents. Based on the total usage of the first mixture of 100 parts by weight, the usage of the poor solvent may be 0 parts by weight to 60 parts by weight, preferably 0 parts by weight to 50 parts by weight. Polyimide polymer

The method for preparing the polyimide polymer is to first dissolve a first mixture in a solvent, wherein the first mixture includes a tetracarboxylic dianhydride compound (a1) and a diamine compound (b1), and perform a polycondensation reaction to form a polyamide polymer. Then, in the presence of a dehydrating agent and a catalyst, further heat and perform a dehydration ring-closing reaction, so that the amide functional group in the polyamide polymer is converted into an imide functional group (i.e., imidization) through the dehydration ring-closing reaction, and the polyimide polymer is obtained.

The solvent used in the polycondensation reaction and the dehydration ring-closing reaction can be the same as the solvent in the liquid crystal alignment agent described below, so it is not described here in detail. Based on the usage of 100 parts by weight of the polyamine polymer, the usage of the solvent used in the dehydration ring-closing reaction can be 200 parts by weight to 2000 parts by weight, preferably 300 parts by weight to 1800 parts by weight.

In order to obtain a better degree of imidization of the polyamide polymer, the operating temperature of the dehydration ring-closing reaction is preferably 40°C to 200°C, more preferably 40°C to 150°C. If the operating temperature of the dehydration ring-closing reaction is lower than 40°C, the imidization reaction is incomplete, thereby reducing the degree of imidization of the polyamide polymer. However, if the operating temperature of the dehydration ring-closing reaction is higher than 200°C, the weight average molecular weight of the obtained polyimide polymer is low.

The imidization rate of the polymer (A-1) is usually 30% or less, preferably 20% or less, and more preferably 10% or less.

The dehydrating agent used in the dehydration ring-closing reaction can be selected from anhydride compounds, wherein specific examples of anhydride compounds include acetic anhydride, propionic anhydride, trifluoroacetic anhydride or a combination thereof. Based on 1 mol of the polyamide polymer, the amount of the dehydrating agent used can be 0.01 mol to 20 mol. Specific examples of the catalyst used in the dehydration ring-closing reaction include (1) pyridine compounds, such as pyridine, trimethylpyridine or dimethylpyridine; (2) tertiary amine compounds, such as triethylamine and other tertiary amine compounds; or a combination of the above compounds. Based on the amount of the dehydrating agent used being 1 mol, the amount of the catalyst used can be 0.5 mol to 10 mol. Polyimide-based block copolymers

The polyimide-based block copolymer includes a polyamic acid block copolymer, a polyimide block copolymer, a polyamic acid-polyimide block copolymer or a combination of the above copolymers.

The method for preparing the polyimide-based block copolymer is preferably to first dissolve the starting material in a solvent and conduct a polycondensation reaction, wherein the starting material includes at least one polyamic acid polymer and/or at least one polyimide polymer mentioned above, and may further include a tetracarboxylic dianhydride compound (a1) and a diamine compound (b1).

The starting materials include the tetracarboxylic dianhydride compound (a1) and the diamine compound (b1) used in the preparation of the polyamide polymer, and the solvent used in the polycondensation reaction can be the same as the solvent in the liquid crystal alignment agent described below, which will not be described in detail herein.

Based on 100 parts by weight of the starting material, the amount of the solvent used in the polycondensation reaction can be 200 to 2000 parts by weight, preferably 300 to 1800 parts by weight. The operating temperature of the polycondensation reaction is preferably 0°C to 200°C, more preferably 0°C to 100°C.

Specific examples of the starting materials include (1) two polyamic acid polymers having different terminal groups and different structures; (2) two polyimide polymers having different terminal groups and different structures; (3) polyamic acid polymers and polyimide polymers having different terminal groups and different structures; (4) a polyamic acid polymer, a tetracarboxylic dianhydride compound and a diamine compound, wherein at least one of the tetracarboxylic dianhydride compound and the diamine compound has a structure different from that of the tetracarboxylic dianhydride compound and the diamine compound used to form the polyamic acid polymer; (5) a polyimide polymer, a tetracarboxylic dianhydride compound and a diamine compound, wherein at least one of the tetracarboxylic dianhydride compound and the diamine compound has a structure different from that of the tetracarboxylic dianhydride compound and the diamine compound used to form the polyimide polymer; (6) a polyamic acid polymer, a polyimide polymer, a tetracarboxylic dianhydride compound, and a diamine compound. (7) two kinds of polyamic acid polymers, tetracarboxylic acid dianhydride compounds and diamine compounds having different structures; (8) two kinds of polyimide polymers, tetracarboxylic acid dianhydride compounds and diamine compounds having different structures; 9) two polyamic acid polymers whose terminal groups are acid anhydride groups and have different structures, and a diamine compound; (10) two polyamic acid polymers whose terminal groups are amine groups and have different structures, and a tetracarboxylic dianhydride compound; (11) two polyimide polymers whose terminal groups are acid anhydride groups and have different structures, and a diamine compound; or (12) two polyimide polymers whose terminal groups are amine groups and have different structures, and a tetracarboxylic dianhydride compound.

In the range that does not affect the efficacy of the present invention, the polyamic acid polymer, polyimide polymer and polyimide-based block copolymer can preferably be a terminal-modified polymer after molecular weight adjustment. By using a terminal-modified polymer, the coating performance of the liquid crystal alignment agent can be improved. The terminal-modified polymer can be prepared by adding a monofunctional compound while the polyamic acid polymer is being subjected to a polycondensation reaction. Specific examples of the monofunctional compound include (1) monoanhydrides, such as maleic anhydride, phthalic anhydride, itaconic anhydride, n-decylsuccinic anhydride, n-dodecylsuccinic anhydride, n-tetradecylsuccinic anhydride or n-hexadecylsuccinic anhydride; (2) monoamine compounds, such as aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, n-undecylamine, n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecylamine, n-octadecylamine or n-eicosylamine; (3) monoisocyanate compounds, such as monoisocyanate compounds such as phenyl isocyanate or naphthyl isocyanate; or combinations of the above monofunctional compounds. However, the present invention is not limited thereto, and the monofunctional compound may further include other suitable monofunctional compounds.

In the liquid crystal alignment agent, based on the total usage of polymer (A-1) and the polymer (A-2) described below being 100 parts by weight, the usage of polymer (A-1) can be 30 parts by weight to 95 parts by weight, preferably 40 parts by weight to 90 parts by weight, and more preferably 50 parts by weight to 90 parts by weight. When the usage of polymer (A-1) in the liquid crystal alignment agent falls within the above range, the liquid crystal alignment film and liquid crystal display element formed by the liquid crystal alignment agent can have a better electric field memory effect. Polymer (A-2)

The liquid crystal alignment agent may further include a polymer (A-2) other than the polymer (A-1). The polymer (A-2) is prepared by reacting a second mixture including a tetracarboxylic dianhydride compound (a2) and a diamine compound (b2).

The tetracarboxylic dianhydride compound (a2) is not particularly limited and may be the same as or different from the tetracarboxylic dianhydride compound (a1) in the above-mentioned polymer (A-1).

The diamine compound (b2) is not particularly limited and may be the same as or different from the diamine compound (b1-2), the diamine compound (b1-3) or the diamine compound (b1-4) in the above-mentioned polymer (A-1).

The method for preparing the polymer (A-2) is not particularly limited and can be, for example, the same as the method for preparing the polymer (A-1), so it will not be described in detail here.

In the liquid crystal alignment agent, based on 100 parts by weight of the total amount of the polymer (A-1) and the polymer (A-2), the amount of the polymer (A-1) can be 5 parts by weight to 70 parts by weight, preferably 10 parts by weight to 60 parts by weight, and more preferably 10 parts by weight to 50 parts by weight. Solvent (B)

Specific examples of the solvent (B) include N-methyl-2-pyrrolidone, γ-butyrolactone, γ-butyrolactamide, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol n-propyl ether, ethylene glycol isopropyl ether, ethylene glycol n-butyl ether, ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, ethylene glycol n-butyl ether diethylene glycol monoethyl ether acetate, N,N-dimethylformamide, N,N-dimethylacetamide (N,N-dimethyl acetamide), or any combination of the above solvents. The solvent (B) is preferably N-methyl-2-pyrrolidone, ethylene glycol n-butyl ether, N,N-dimethylacetamide, or a combination of the above solvents. However, the present invention is not limited thereto, and the solvent (B) may further include other suitable solvents. The solvent (B) may be used alone or in combination of multiple solvents.

When the liquid crystal alignment agent includes a polymer (A-1) and a solvent (B), based on 100 parts by weight of the polymer (A-1), the amount of the solvent (B) used can be 1000 parts by weight to 3500 parts by weight, preferably 1000 parts by weight to 3200 parts by weight, and more preferably 1000 parts by weight to 3000 parts by weight.

When the liquid crystal alignment agent comprises polymer (A-1), polymer (A-2) and solvent (B), based on the total usage of polymer (A-1) and polymer (A-2) being 100 parts by weight, the usage of solvent (B) may be 1000 parts by weight to 3500 parts by weight, preferably 1000 parts by weight to 3200 parts by weight, and more preferably 1000 parts by weight to 3000 parts by weight. Additive (C)

The liquid crystal alignment agent may also selectively add an additive (C) within the scope of not affecting the efficacy of the present invention. The additive (C) may be an epoxy compound, a silane compound having a functional group, or a combination thereof. The additive (C) is used to improve the adhesion between the liquid crystal alignment film and the substrate surface. The additive (C) may be used alone or in combination.

Specific examples of epoxy compounds include 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-dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol, N,N,N', N'-tetracycloxypropyl-m-xylene diamine, 1,3-bis(N,N-dicycloxypropylaminomethyl)cyclohexane, N,N,N',N'-tetracycloxypropyl-4,4'-diaminodiphenylmethane, N,N-dicycloxypropyl-p-cycloxypropyloxyaniline, 3-(N-allyl-N-cycloxypropyl)aminopropyltrimethoxysilane or 3-(N,N-dicycloxypropyl)aminopropyltrimethoxysilane or a combination thereof. However, the present invention is not limited thereto, and the epoxy compound may further include other suitable epoxy compounds.

Based on 100 parts by weight of the polymer (A-1), the amount of the epoxy compound used is generally 40 parts by weight or less, preferably 0.1 to 30 parts by weight.

Specific examples of the silane compound having a functional group include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltrimethoxysilane, and the like. ethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4,7-triazdecane, 10-triethoxysilyl-1,4,7-triazdecane, 9-trimethoxysilyl-3,6-diazononyl acetate, 9-triethoxysilyl-3,6-diazononyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis(ethylene oxide)-3-aminopropyltrimethoxysilane, N-bis(ethylene oxide)-3-aminopropyltriethoxysilane, or a combination thereof. However, the present invention is not limited thereto, and the silane compound having a functional group may further include other suitable silane compounds having a functional group.

Based on the usage of polymer (A-1) being 100 parts by weight, the usage of silane compound is generally less than 10 parts by weight, preferably 0.5 parts by weight to 10 parts by weight. > Method for preparing liquid crystal alignment agent >

The preparation method of the liquid crystal alignment agent of the present invention is not particularly limited, and it can be prepared by a general mixing method. For example, a solvent (B) is added to the polymer (A-1) or a mixture of the polymer (A-1) and the polymer (A-2) at a temperature of 0°C to 200°C, and an additive (C) can be optionally added; and then the mixture is continuously stirred with a stirring device until dissolved. The temperature at which the polymer is added to the solvent (B) is preferably 20°C to 60°C.

At 25°C, the viscosity of the liquid crystal alignment agent of the present invention is generally 15 cps to 35 cps, preferably 17 cps to 33 cps, and more preferably 20 cps to 30 cps. > Method for preparing liquid crystal alignment film >

The liquid crystal alignment agent of the present invention can form a liquid crystal alignment film by a photoalignment method.

The method of forming a liquid crystal alignment film is, for example, to apply a liquid crystal alignment agent onto a substrate to form a coating, and irradiate the coating with polarized or non-polarized ultraviolet light from a direction inclined relative to the coating surface; or irradiate the coating with polarized ultraviolet light from a direction perpendicular to the coating surface, thereby imparting liquid crystal alignment energy to the coating.

First, the liquid crystal alignment agent of the present invention is applied to the transparent conductive film side of the substrate provided with a patterned transparent conductive film by an appropriate coating method such as roller coating, spin coating, printing or ink-jet. After coating, the coated surface is subjected to a pre-bake treatment and then a post-bake treatment to form a coating film. The purpose of the above-mentioned pre-bake treatment is to volatilize the organic solvent in the pre-coating layer. The conditions of the pre-bake treatment are, for example, 0.1 to 5 minutes at a temperature of 40°C to 120°C. The temperature of the post-bake treatment can be 120°C to 300°C, preferably 150°C to 250°C. The post-baking treatment time may be 5 to 200 minutes, more preferably 10 to 100 minutes. The coating film thickness after post-baking is preferably 0.001 μm to 1 μm, more preferably 0.005 μm to 0.5 μm.

The substrate may be, for example, a transparent substrate made of glass such as float glass or sodium calcium glass; or plastic such as polyethylene terephthalate, polybutylene terephthalate, polyether sulfide, or polycarbonate.

The transparent conductive film may be a NESA film formed of SnO ₂ or an Indium Tin Oxide (ITO) film formed of In ₂ O ₃ -SnO _2. To form these transparent conductive film patterns, photo-etching technology or a method of using a mask when forming the transparent conductive film may be used.

When applying the liquid crystal alignment agent, in order to improve the adhesion between the substrate or the transparent conductive film and the coating, a functional silane compound, a titanium ester compound (titanate), etc. can be pre-coated on the substrate and the transparent conductive film.

Next, a liquid crystal alignment film is formed from the coating by irradiating the coating with polarized or unpolarized ultraviolet light to impart liquid crystal alignment ability. Here, the radiation may include, for example, ultraviolet light with a wavelength of 150 to 800 nm and visible light, and preferably ultraviolet light with a wavelength of 300 to 400 nm. When the radiation used is polarized light (linearly polarized light or partially polarized light), it can be irradiated from a direction perpendicular to the coating surface, and in order to impart a pre-tilt angle, it can also be irradiated from an oblique direction. On the other hand, when irradiating unpolarized radiation, it must be irradiated from a direction oblique to the coating surface.

The light source for irradiating radiation may be, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, or an excimer laser. The ultraviolet light in the above-mentioned preferred wavelength region can be obtained by using the above-mentioned light source in combination with, for example, a filter, a diffraction grating, or the like.

The radiation exposure is preferably 1 J/ ^m2 or more and less than 10000 J/ ^m2 , more preferably 10 J/ ^m2 to 3000 J/ ^m2 . In addition, when imparting liquid crystal alignment ability to a coating formed by a conventionally known liquid crystal alignment agent by a photoalignment method, a radiation exposure of 10000 J/ ^m2 or more is required. However, if the liquid crystal alignment agent of the present invention is used, even if the radiation exposure during the photoalignment method is 3000 J/m2 ^or less, further 1000 J/m2 ^or less, and further 300 J/ ^m2 or less, a good liquid crystal alignment ability can be imparted, thereby helping to reduce the manufacturing cost of liquid crystal display elements. > Method for manufacturing liquid crystal display element >

The liquid crystal display element of the present invention comprises a liquid crystal alignment film formed by the above liquid crystal alignment agent. The liquid crystal display element of the present invention can be manufactured as follows.

Two substrates with liquid crystal alignment films formed thereon are prepared, and liquid crystal is placed between the two substrates to produce a liquid crystal cell. For example, the following two methods can be used to produce a liquid crystal cell.

The first method: First, two substrates are arranged opposite to each other with a gap (cell gap) between them so that their respective liquid crystal alignment films face each other; the peripheral parts of the two substrates are bonded together using a sealant; the liquid crystal is injected into the cell gap divided by the substrate surface and the sealant; and the injection hole is closed, so that a liquid crystal cell can be manufactured.

The second method is called the One Drop Fill (ODF) method. First, a UV-curable sealing material is applied to a predetermined portion of one of the two substrates that form the liquid crystal alignment film. Liquid crystal is dripped onto the surface of the liquid crystal alignment film. Then, the other substrate is attached so that the liquid crystal alignment films face each other. Next, the entire surface of the substrate is irradiated with UV light to cure the sealing agent, thereby manufacturing a liquid crystal cell.

In any of the above methods, it is desirable to heat the liquid crystal cell to a temperature at which the liquid crystal is in an isotropic phase and then slowly cool it to room temperature to remove the flow alignment when the liquid crystal is filled.

Then, by attaching a polarizing plate to the outer surface of the liquid crystal cell, the liquid crystal display element of the present invention can be obtained. Here, when the liquid crystal alignment film is horizontally aligned, by adjusting the angle formed by the polarization direction of the linear polarized light radiation irradiated in the two substrates forming the liquid crystal alignment film and the angle between each substrate and the polarizing plate, a liquid crystal display element having a TN type or STN type liquid crystal cell can be obtained. On the other hand, when the liquid crystal alignment film is vertically aligned, by constituting the liquid crystal cell so that the directions of the easy-to-align axes of the two substrates forming the liquid crystal alignment film are parallel, and bonding the polarizing plate to the liquid crystal cell so that the polarization direction forms a 45° angle with the easy-to-align axis, a liquid crystal display element having a vertically aligned liquid crystal cell can be formed.

Specific examples of the sealant include alumina balls as spacers or epoxy resins containing a curing agent.

Specific examples of liquid crystals include nematic liquid crystals and discotic liquid crystals.

In the case of a TN-type or STN-type liquid crystal cell, specific examples of nematic liquid crystals having positive dielectric anisotropy preferably include biphenyl-based liquid crystals, phenyl cyclohexane-based liquid crystals, ester liquid crystals, terphenyl liquid crystals, biphenyl cyclohexane-based liquid crystals, pyrimidine-based liquid crystals, dioxane-based liquid crystals, bicyclooctane-based liquid crystals, cubane-based liquid crystals, and the like. In addition, the aforementioned liquid crystal may be further added with additives such as cholesteric liquid crystals such as cholesterol chloride, cholesterol nonabenzoate, and cholesterol carbonate; chiral agents sold under the trade names "C-15" and "CB-15" (manufactured by Merck); and ferroelectric liquid crystals such as p-decyloxybenzylidene-p-amino-2-methyl butyl cinnamate.

On the other hand, in the case of a vertically aligned liquid crystal cell, specific examples of nematic liquid crystals with negative dielectric anisotropy preferably include dicyanobenzene-based liquid crystals, pyridazine-based liquid crystals, Schiff base-based liquid crystals, azoxy-based liquid crystals, biphenyl-based liquid crystals, phenyl cyclohexane-based liquid crystals or a combination thereof.

The polarizing plate used on the outside of the liquid crystal cell can be a polarizing plate formed by sandwiching a polarizing film called "H film" made by stretching and aligning polyvinyl alcohol and absorbing iodine with a cellulose acetate protective film, or a polarizing plate formed by the H film itself.

The liquid crystal display element of the present invention manufactured in this way has excellent display performance, and the display performance will not deteriorate even if used for a long time.

1 is a side view of a liquid crystal display device according to an embodiment of the present invention. The liquid crystal display device 100 includes a first unit 110, a second unit 120 and a liquid crystal unit 130, wherein the second unit 120 is separated from the first unit 110 and the liquid crystal unit 130 is disposed between the first unit 110 and the second unit 120.

The first unit 110 includes a first substrate 112, a first conductive film 114 and a first liquid crystal alignment film 116, wherein the first conductive film 114 is located between the first substrate 112 and the first liquid crystal alignment film 116. In addition, the first liquid crystal alignment film 116 in the first unit 110 is located on a side of the first unit 110 close to the liquid crystal unit 130.

The second unit 120 includes a second substrate 122, a second conductive film 124, and a second liquid crystal alignment film 126, wherein the second conductive film 124 is located between the second substrate 122 and the second liquid crystal alignment film 126. In addition, the second liquid crystal alignment film 126 in the second unit 120 is located on a side of the second liquid crystal alignment film 126 close to the liquid crystal unit 130. In other words, the liquid crystal unit 130 is located between the first liquid crystal alignment film 116 and the second liquid crystal alignment film 126.

The first substrate 112 and the second substrate 122 are selected from transparent materials, wherein the transparent materials include alkali-free glass, sodium calcium glass, hard glass (Pyles glass), quartz glass, polyethylene terephthalate, polybutylene terephthalate, polyether sulfide or polycarbonate used in liquid crystal display devices. However, the present invention is not limited thereto, and the materials of the first substrate 112 and the second substrate 122 can also be selected from other suitable materials.

The materials of the first conductive film 114 and the second conductive film 124 are selected from materials such as tin oxide (SnO ₂ ) or indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ). However, the present invention is not limited thereto, and the materials of the first conductive film 114 and the second conductive film 124 may also be selected from other suitable materials.

The first liquid crystal alignment film 116 and the second liquid crystal alignment film 126 are each the above-mentioned liquid crystal alignment films, and their function is to make the liquid crystal unit 130 form a pre-tilt angle. In addition, when a voltage is applied to the first conductive film 114 and the second conductive film 124, an electric field can be generated between the first conductive film 114 and the second conductive film 124. This electric field can drive the liquid crystal unit 130, thereby changing the arrangement of the liquid crystal molecules in the liquid crystal unit 130. Preparation Example of Diamine Compound (b1-1)

Preparation Examples 1 to 6 of the diamine compound (b1-1) are described below. Preparation Example 1

The compound represented by formula (I-1) (hereinafter referred to as "diamine compound (b1-1-1)") was synthesized according to the following synthesis route 1. [Synthesis route 1]

Place 105 g of hydroquinone, 135 g of potassium carbonate (K ₂ CO ₃ ) and 700 ml of acetonitrile (ACN) in a 3-liter four-necked flask, stir and heat to 80°C. Then drop a mixed solution of 100 g of 4,4,4-trifluorobutyl methanesulfonate and 500 ml of acetonitrile into the four-necked flask. After the drop is complete, keep the temperature at 80°C for 4 hours. Then, add 190 g of a 25 wt% sodium hydroxide aqueous solution and reflux at 80°C for 30 minutes. Then, add 415 ml of water and keep the temperature at 80°C for 1 hour. After the reaction was completed, filtration was performed, and the filtrate was collected and dried, and then separated by column chromatography to obtain about 65 g of R1OH solid.

Next, 120 g of R1OH solid, 95 g of 4-formylcinnamic acid, 12 g of 4-dimethylaminopyridine (DMAP) and 1080 ml of dichloromethane (CH ₂ Cl ₂ ) were placed in a 2-liter four-necked flask and stirred. During the stirring process, 125 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC.HCl) was added, and after the addition, the temperature was raised to 40°C and refluxed at 40°C for 6 hours. After the reaction was completed, the mixture was extracted twice with 540 ml of water, and the organic layer was collected and dehydrated with anhydrous magnesium sulfate, and then filtered and dried. The solid obtained after drying was heated and dissolved in 300 g of isopropanol, and then allowed to stand for crystallization after cooling. The crystals were collected by filtration and dried to obtain about 130 g of R3A solid.

Then, 64 g of R3A solid and 560 ml of dimethylformamide (DMF) were placed in a 3-liter three-necked flask and stirred to dissolve, and then 150 g of potassium peroxymonosulfate (Oxone) was added and reacted at room temperature for 3 hours. After the reaction was completed, the solution was drained and the solid was washed 3 times with 1300 ml of water. Thereafter, it was washed once with 1300 ml of methanol. The washed solid was collected and vacuum dried to obtain about 55 g of R3B solid.

Next, 67 g of R3B solid, 60 g of 2-(N,N-di-Boc-2,4-diaminophenyl)-1-ethanol (t-Boc DPE), 2 g of 4-dimethylaminopyridine and 340 ml of dichloromethane were placed in a 5-liter four-necked flask and stirred. 40 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloric acid (EDC.HCl) was added during stirring, and the temperature was raised to 40°C after addition, and refluxed at 40°C for 6 hours. After the reaction was completed, the mixture was extracted twice with 2500 ml of water, and the organic layer was collected and filtered and dried after dehydration with anhydrous magnesium sulfate. The solid obtained after drying was heated and dissolved in 370 g of isopropanol, and then allowed to stand for crystallization after cooling. The crystals were collected by filtration and dried to obtain about 100 g of R4B solid.

Then, 100 g of R4B solid and 1400 ml of dichloromethane were placed in a 5-liter four-necked flask and stirred. During the stirring process, 135 g of Tin(II) trifluoromethanesulfonate (Sn(OTf) ₂ ) was added, and after the addition, the temperature was raised to 40°C in nitrogen and refluxed for 1.5 hours. After the reaction was completed, 1600 ml of ethyl acetate was poured into the flask and stirred. Then, 970 ml of 2.5M sodium hydroxide aqueous solution was poured into the flask and stirred for 30 minutes. Then, the solution was poured into a 2-liter separatory flask, allowed to stand, and the upper organic layer was collected. Subsequently, the mixture was extracted 4 times with 970 ml of a 2.5 M sodium hydroxide aqueous solution, and then extracted 10 times with 970 ml of water. The organic layer after extraction was dehydrated with anhydrous magnesium sulfate, filtered and dried, and then washed with 200 g of methanol, filtered and dried to collect the solid. The solid was then dissolved in 300 g of acetonitrile by heating, and allowed to stand for crystallization after cooling. The crystals were collected by filtration and dried to obtain about 48 g of RPADA solid (i.e., diamine compound b1-1-1 represented by formula (I-1)). Preparation Example 2

The compound represented by formula (I-2) (hereinafter referred to as "diamine compound (b1-1-2)") was synthesized according to the following Synthesis Route 2. [Synthesis Route 2]

65 g of 4-methylcinnamic acid, 100 g of 4-(4-heptylcyclohexyl)phenol (7CPO) and 4.5 g of 4-dimethylaminopyridine were placed in a 2-liter four-necked flask. 730 ml of dichloromethane was added to the four-necked flask, and 84 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloric acid (EDC.HCl) was added during stirring. Then, the mixture was reacted at 40°C for 6 hours. After the reaction was completed, water was added for extraction, and the organic layer was collected and filtered to dryness after dehydration with anhydrous magnesium sulfate. The solid obtained after drying was washed with isopropanol by heating, and then filtered and collected to obtain about 130 g of R3CHO solid.

Next, 80 g of R3CHO solid and 620 ml of dimethylformamide were placed in a 1-liter three-necked flask and stirred. After the R3CHO solid was dissolved, 170 g of potassium hydrogen persulfate (Oxone) was added and reacted at room temperature for 3 hours. After the reaction was completed, the solvent was drained to obtain a solid, and the solid was washed with pure water and methanol. After washing, vacuum drying was performed to obtain about 75 g of R3COOH solid.

Then, 46.7 g of R3COOH solid and 250 ml of toluene were placed in a 0.5 liter three-necked flask and stirred to dissolve. Then, 0.09 g of dimethylformamide (DMF) was added and the temperature was raised to 75°C. Subsequently, 13.6 g of thionyl chloride (SOCl ₂ ) was slowly dripped in, and after the dripping was completed, the temperature was raised to 80°C and reacted for 5 minutes. Then, the temperature was lowered to 40°C. 26.5 g of 2,4-dinitrophenyl-ethanol and 0.6 g of 4-dimethylaminopyridine were dissolved in 12.4 g of pyridine and dripped into the above three-necked flask and stirred for 12 hours. Then, the temperature was raised to 60°C, 20 ml of methanol was added, and the temperature was maintained at 45°C for 1 hour. Finally, the solvent was drained and washed with methanol to obtain about 57 g of precipitated R3DiNO-L solid.

Next, 48.4 g of R3DiNO-L solid and 440 ml of anisole were placed in a 3-liter four-necked flask and stirred. In addition, 186 ml of pure water and 7.7 g of Pt/C were placed in a 2-liter flask and stirred, and then 0.13 g of ammonium metavanadate (NH ₄ VO ₃ ) and 0.7 g of hypophosphorous acid (H ₃ PO ₂ ) aqueous solution (50 wt%) were added to prepare a mixed solution. The above mixed solution was poured into a four-necked flask and heated to 65°C. Subsequently, 30 g of hydrazine (NH ₂ NH ₂ ) was dripped in. After all the drips were added, the temperature was raised to 80°C and reacted for 4 hours. Subsequently, the solution was filtered, and the filtrate was extracted with ethyl acetate and water and then dried to obtain a solid. Next, the solid was washed with ethyl acetate by heating, and then filtered and collected to obtain about 30 g of RPADA3 solid (ie, diamine compound b1-1-2 represented by formula (I-2)). Preparation Example 3

The compound represented by formula (I-3) (hereinafter referred to as "diamine compound (b1-1-3)") was synthesized according to the following Synthesis Route 3. [Synthesis Route 3]

Place 140 g of tetrahydropyranyloxy phenol, 180 g of 4-(4,4,4-trifluorobutoxy)benzoic acid and 8.8 g of 4-dimethylaminopyridine in a 3-liter four-necked flask. Add 1600 g of dichloromethane to the four-necked flask, and add 150 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloric acid (EDC.HCl) while stirring. After the addition, react at room temperature for 8 hours. After the reaction is complete, add water for extraction, collect the organic layer, remove water with anhydrous magnesium sulfate, filter and dry. The solid obtained after drying is then washed with isopropanol and heated. After washing, the solid was collected by filtration and vacuum dried to obtain about 270 g of R5THP solid.

Next, 270 g of R5THP solid, 65 ml of methanol and 1200 ml of dichloromethane were placed in a 2 liter four-necked flask and stirred. During the stirring process, 170 g of 12 wt% p-toluenesulfonic acid acetic acid solution was added dropwise. After addition, the mixture was reacted at room temperature for 2 hours. After the reaction was completed, water was added for extraction, and the solvent was dried after extraction to obtain about 210 g of R5OH solid.

Then, 70 grams of R5OH solid, 36 grams of 4-formylcinnamic acid and 2.5 grams of 4-dimethylaminopyridine were placed in a 1-liter four-necked flask, and 550 grams of dichloromethane were added and stirred. Subsequently, 47.3 grams of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloric acid (EDC.HCl) were added dropwise during stirring. After the addition, the mixture was reacted at 40°C for 8 hours. After the reaction was completed, water was added for extraction, the organic layer was collected and filtered after dehydration with anhydrous magnesium sulfate. The solid obtained after drying was then washed with isopropanol and heated. After washing, the solid was collected by filtration and vacuum dried to obtain about 87 grams of R5BCHO solid.

Next, 87 g of R5BCHO solid and 583 ml of dimethylformamide were placed in a 1-liter three-necked flask and stirred to dissolve. Then 160 g of potassium persulfate (Oxone) was added and reacted at room temperature for 3 hours. After the reaction was completed, the solution was drained and the solid was washed 3 times with 1600 ml of water. Thereafter, it was washed once with 800 ml of methanol. The washed solid was collected and vacuum dried to obtain about 44 g of R5BCOOH solid.

Then, 44 g of R5BCOOH solid, 30 g of 2-(N,N-di-tert-butyloxycarbonyl-2,4-diaminophenyl)-1-ethanol (t-Boc DPE), 2 g of 4-dimethylaminopyridine and 850 ml of dichloromethane were placed in a 1 liter four-necked flask and stirred. During the stirring process, 20 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloric acid (EDC.HCl) was added, and the mixture was refluxed at room temperature for 6 hours. After the reaction was completed, the mixture was extracted with 350 ml of water, and the organic layer was collected and filtered to dryness after dehydration with anhydrous magnesium sulfate. The solid obtained after drying was heated and dissolved in isopropanol, and then allowed to stand for crystallization after cooling. The crystals were collected by filtration and dried to obtain about 70 g of R5BBoc solid.

Next, 50 g of R5BBoc solid and 1200 ml of dichloromethane were placed in a 5-liter four-necked flask and stirred. 62 g of tin(II) trifluoromethanesulfonate (Sn(OTf) ₂ ) was added during the stirring process. After the addition, the temperature was raised to 40°C in nitrogen and refluxed for 1.5 hours. After the reaction was completed, 2000 ml of ethyl acetate was poured into the flask and stirred. Then, 450 ml of 2.5M sodium hydroxide aqueous solution was poured into the flask and stirred for 30 minutes. Then, the solution was poured into a 2-liter separatory flask, left to stand, and the upper organic layer was collected. Subsequently, the mixture was extracted four times with 450 ml of a 2.5 M sodium hydroxide aqueous solution, and then extracted four times with 200 ml of water. The organic layer after extraction was dehydrated with anhydrous magnesium sulfate, filtered and dried, and then washed with methanol, filtered and dried to collect the solid. The solid was then dissolved in acetonitrile by heating, cooled, and allowed to stand for crystallization. The crystals were filtered, collected, and dried to obtain about 28 g of RPADA5B solid (i.e., diamine compound b1-1-3 represented by formula (I-3)). Preparation Example 4

The compound represented by the formula (I-6) (hereinafter referred to as "diamine compound (b1-1-4)") was synthesized according to the following Synthesis Route 4. [Synthesis Route 4]

285 g of 4-hydroxycinnamic acid (4-hydroxycinnamic acid), 293 g of 3,4-Dihydro-2H-pyran (DHP) and 1800 ml of dichloromethane were placed in a 3-liter four-necked flask and stirred evenly. During the stirring process, 20.6 g of trifluoroacetic acid (2,2,2-Trifluoroacetic acid, TFA) was added dropwise. Then, the mixture was reacted at 40°C for 6 hours. After the reaction was completed, the solid was collected by vacuum filtration. The collected solid was then washed with 1300 g of methanol at 50°C and then dried to obtain about 345 g of R4-COOH solid.

Next, 124 g of R4-COOH solid, 137 g of 4-(4-heptylcyclohexyl)phenol (7CPO) and 6.1 g of 4-dimethylaminopyridine were placed in a 3 liter four-necked flask. 830 ml of dichloromethane was added to the four-necked flask, and 105 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloric acid (EDC.HCl) was added during stirring. Afterwards, the reaction was carried out at 40°C for 8 hours. After the reaction was completed, water was added for extraction, the organic layer was collected and filtered after dehydration with anhydrous magnesium sulfate. The solid obtained after drying was then washed with isopropanol and heated. After washing, the solid was collected by filtration and vacuum dried to obtain about 210 g of R4-7CPO solid.

Then, 110 g of R4-7CPO solid and 670 ml of dichloromethane were added to a 3-liter flask and stirred. 140 g of 12 wt% p-toluenesulfonic acid acetic acid solution was added dropwise during stirring. Thereafter, the reaction was carried out at room temperature for 2 hours. After the reaction was completed, a small amount of methanol was added. Subsequently, the solvent was drained, and the mixture was extracted with dichloromethane and saturated sodium bicarbonate aqueous solution, and finally extracted with water, and the organic layer was collected. The organic layer was dehydrated with anhydrous magnesium sulfate, filtered and dried, and about 80 g of R4-OH solid was obtained.

Next, 20.7 g of 2,4-dinitrophenylethanol and 96.5 g of toluene were placed in a 0.5 liter three-necked flask, and 0.1 g of dimethylformamide was added, and the temperature was raised to 75°C. Subsequently, 12 g of sulfoxide chloride was slowly added, and the temperature was maintained at 80°C after the addition, and the reaction was continued. After the solution became yellow and clear, the temperature was lowered to 30°C. 46 g of R4-OH solid and 0.56 g of 4-dimethylaminopyridine were dissolved in 22 g of pyridine, and then dripped into the three-necked flask. After the addition was completed, the mixture was stirred at room temperature for 12 hours, and then the temperature was raised to 60°C and 80 g of methanol was added. After the temperature was maintained at 45°C for 1 hour, the solvent was drained to obtain about 44 g of R4-DiNO solid.

Then, 80 g of R4-DiNO solid, 85 g of reduced iron and 40 g of ammonium chloride (NH ₄ Cl) were placed in a 5 liter four-necked flask, 950 g of water and 1050 g of ethyl acetate (EA) were added to the flask, stirred evenly, and then heated to 70°C and reacted at 70°C for 2 hours. After the reaction was completed, diatomaceous earth was filtered at 70°C, and the aqueous layer was removed after the filtrate was separated, and the organic layer was collected and dehydrated with anhydrous magnesium sulfate, filtered and dried to obtain about 35 g of RPADA4 solid (i.e., diamine compound b1-1-4 represented by formula (I-6)). Preparation Example 5

The compound represented by formula (I-7) (hereinafter referred to as "diamine compound (b1-1-5)") was synthesized according to the following synthesis route 5. [Synthesis route 5]

65 g of 4-methylcinnamic acid, 100 g of 4-(4-heptylcyclohexyl)phenol (7CPO) and 4.5 g of 4-dimethylaminopyridine were placed in a 2-liter four-necked flask. 730 ml of dichloromethane was added to the four-necked flask, and 84 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloric acid (EDC.HCl) was added during stirring. Then, the mixture was reacted at 40°C for 6 hours. After the reaction was completed, water was added for extraction, the organic layer was collected and filtered after dehydration with anhydrous magnesium sulfate. The solid obtained after drying was then washed with isopropanol by heating. Afterwards, the solid was filtered and collected to obtain about 130 g of R3CHO solid.

Next, 80 g of R3CHO solid and 620 ml of dimethylformamide were placed in a 1-liter three-necked flask and stirred. After the R3CHO solid was dissolved, 170 g of potassium persulfate (Oxone) was added and reacted at room temperature for 3 hours. After the reaction was completed, the solvent was drained to obtain a solid, which was then washed with pure water and methanol. After washing, the solid was collected by filtration and vacuum dried to obtain about 75 g of R3COOH light yellow solid.

Then, add 68.5 g of R3COOH light yellow solid, 28.1 g of 2,4-dinitrophenol, 3.73 g of 4-dimethylaminopyridine and 1250 ml of 0.125M dichloromethane into a 1 liter four-necked flask and stir. Add 34.5 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloric acid (EDC.HCl) during stirring. Then, reflux the reaction at 40°C for 6 hours. After the reaction is completed, add water for extraction, collect the organic layer, remove water with anhydrous magnesium sulfate, filter and dry. The solid obtained after drying is then washed with isopropanol and heated. After washing, the solid was collected by filtration and vacuum dried to obtain about 50 g of R3DiNO solid.

Next, 28.3 g of R3DiNO solid and 270 ml of anisole were placed in a 2-liter four-necked flask and stirred; in addition, 115 ml of pure water and 6 g of Pt/C were placed in a 2-liter flask and stirred, and then 0.08 g of ammonium metavanadate and 0.42 g of hypophosphorous acid aqueous solution (50 wt%) were added to prepare a mixed solution. The above mixed solution was poured into a four-necked flask and heated to 65°C. Subsequently, 18.4 g of hydrazine was dripped in, and after all dripped in, the temperature was raised to 80°C and reacted for 4 hours. Subsequently, the solution was filtered, and the filtrate was extracted with ethyl acetate and water and then dried to obtain a solid. Next, the solid was washed with ethyl acetate by heating, and then filtered and collected to obtain about 10 g of RPADA3M solid (ie, diamine compound b1-1-5 represented by formula (I-7)). Preparation Example 6

The compound represented by formula (I-9) (hereinafter referred to as "diamine compound (b1-1-6)") was synthesized according to the following Synthesis Route 6. [Synthesis Route 6]

Place 45 g of 4-methylcinnamic acid, 100 g of 5α-cholestan-3β-ol and 3.2 g of 4-dimethylaminopyridine in a 2-liter four-necked flask. Add 520 ml of dichloromethane to the four-necked flask, and add 60 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloric acid (EDC.HCl) while stirring. Then, react at 40°C for 6 hours. After the reaction is completed, add water for extraction, collect the organic layer, remove water with anhydrous magnesium sulfate, filter and dry. The solid obtained after drying is then washed with isopropanol by heating. Thereafter, the solid was filtered and collected to obtain about 120 g of R6CHO solid.

Next, 80 g of R6CHO solid and 500 ml of dimethylformamide were placed in a 1-liter three-necked flask and stirred. After the R6CHO solid was dissolved, 135 g of potassium persulfate (Oxone) was added and reacted at room temperature for 3 hours. After the reaction was completed, the solvent was drained to obtain a solid, which was then washed with pure water and methanol. After washing, the solid was collected by filtration and vacuum dried to obtain about 60 g of R6COOH solid.

Then, 120 g of R6COOH solid and 200 ml of toluene were placed in a 1 liter three-necked flask and stirred to dissolve, and then 0.2 g of dimethylformamide was added and the temperature was raised to 75°C. Subsequently, 23 g of sulfoxide chloride was slowly dripped in, and the temperature was raised to 80°C after the dripping was completed, and the reaction was carried out at 80°C for 5 minutes. Then, the temperature was lowered to 30°C. 40 g of 2,4-dinitrophenylethanol and 1 g of 4-dimethylaminopyridine were dissolved in 40 g of pyridine and dripped into the above three-necked flask, and the stirring was continued for 12 hours. Afterwards, the temperature was raised to 60°C, and 150 ml of methanol was added, and the temperature was maintained at 45°C for 1 hour. Finally, the solvent was drained and then washed with methanol to obtain about 90 g of precipitated R6DiNO solid.

Next, 50 g of R6DiNO solid and 400 ml of anisole were placed in a 1-liter four-necked flask and stirred; in addition, 160 ml of pure water and 10 g of Pt/C were placed in a 2-liter flask and stirred, and then 0.12 g of ammonium metavanadate and 0.6 g of hypophosphorous acid aqueous solution (50 wt%) were added to prepare a mixed solution. The above mixed solution was poured into a four-necked flask and heated to 65°C. Subsequently, 26 g of hydrazine was dripped in, and after all dripped in, the temperature was raised to 80°C and reacted for 4 hours. Subsequently, the solution was filtered, and the filtrate was extracted with ethyl acetate and water and then dried to obtain a solid. Next, the solid was washed with ethyl acetate by heating, and then filtered and collected to obtain about 20 g of RPADA6 solid (i.e., diamine compound b1-1-6 represented by formula (I-9)). Preparation Example of Diamine Compound (b1-2)

For example, the preparation example of diamine compound (b1-2) can refer to the content of Taiwan Patent Publication No. TW201536862A. In detail, the preparation method of the compound represented by formula (II-10) (hereinafter referred to as "diamine compound (b1-2-1)") can refer to the content of page 40, line 8 to page 41, line 21 of the aforementioned patent disclosure; the preparation method of the compound represented by formula (II-18) (hereinafter referred to as "diamine compound (b1-2-2)") can refer to the content of page 41, line 22 to page 44, line 1 of the aforementioned patent disclosure; the compound represented by formula (II-24) (hereinafter referred to as "diamine compound (b1-2-3)" For the preparation method of the compound represented by formula (II-22) (hereinafter referred to as "diamine compound (b1-2-4)"), reference may be made to the contents of page 45, line 26 to page 47, line 11 of the aforementioned patent disclosure; and for the preparation method of the compound represented by formula (II-26) (hereinafter referred to as "diamine compound (b1-2-5)"), reference may be made to the contents of page 47, line 12 to page 49, line 4 of the aforementioned patent disclosure. Preparation Example of Diamine Compound (b1-3)

For example, the preparation example of the diamine compound (b1-3) can refer to the content of Taiwan Patent Publication No. TW201546120A. In detail, the preparation method of the compound represented by formula (III-1) (hereinafter referred to as "diamine compound (b1-3-1)") can refer to the contents of paragraphs [0144] to [0146] of the aforementioned patent disclosure; the preparation method of the compound represented by formula (III-2) (hereinafter referred to as "diamine compound (b1-3-2)") can refer to the contents of paragraphs [0147] to [0149] of the aforementioned patent disclosure; the preparation method of the compound represented by formula (III-3) (hereinafter referred to as "diamine compound (b1-3-3)") can refer to the contents of paragraphs [0150] to [0152] of the aforementioned patent disclosure. The preparation method of the compound represented by formula (III-4) (hereinafter referred to as "diamine compound (b1-3-4)") can refer to the contents of paragraphs [0153] to [0155] of the aforementioned patent disclosure; the preparation method of the compound represented by formula (III-5) (hereinafter referred to as "diamine compound (b1-3-5)") can refer to the contents of paragraphs [0156] to [0158] of the aforementioned patent disclosure; and the preparation method of the compound represented by formula (III-6) (hereinafter referred to as "diamine compound (b1-3-6)") can refer to the contents of paragraphs [0159] to [0161] of the aforementioned patent disclosure. Synthesis Example of Polymer (A-1)

Synthesis Examples A-1-1-1 to A-1-1-6, Synthesis Examples A-1-2-1 to A-1-2-6, Synthesis Examples A-1-3-1 to A-1-3-6, and Synthesis Examples A-1-4-1 to A-1-4-6 of the polymer (A- 1 ) are described below.

A nitrogen inlet, a stirrer, a condenser and a thermometer were set on a 500 ml four-necked conical flask, and nitrogen was introduced. Then, 0.025 mol (50 mol%) of the diamine compound b1-1-1 obtained in Preparation Example 1, 0.025 mol (50 mol%) of other diamine compounds (b1-4-1) and 80 g of N-methyl-2-pyrrolidone (abbreviated as NMP) were added to the four-necked conical flask, and stirred at room temperature until dissolved. Then, 0.05 mol (100 mol%) of 2,3,5-tricarboxycyclopentylacetic dianhydride (abbreviated as a1-1) and 20 g of NMP were added, and the mixture was reacted at room temperature for 2 hours. After the reaction was completed, the reaction solution was poured into 1500 ml of water to precipitate the polymer. Then, the obtained polymer was filtered, and the washing and filtering were repeated three times with methanol, and the polymer was placed in a vacuum oven and dried at a temperature of 60°C to obtain polymer A-1-1-1. Synthesis Examples A-1-1-2 to A-1-1-6 , Synthesis Examples A-1-2-1 to A-1-2-6 , Synthesis Examples A-1-3-1 to A-1-3-6 , and Synthesis Examples A-1-4-1 to A-1-4-6

Synthesis Examples A-1-1-2 to A-1-1-6, Synthesis Examples A-1-2-1 to A-1-2-6, Synthesis Examples A-1-3-1 to A-1-3-6, and Synthesis Examples A-1-4-1 to A-1-4-6 are prepared by the same steps as Synthesis Example A-1-1-1, except that the types of polymer raw materials and their amounts used are changed (as shown in Table 1). Synthesis Examples of Polymer (A-2) Synthesis Examples A-2-1 to A-2-6

Synthesis Examples A-2-1 to A-2-6 were prepared by the same steps as Synthesis Example A-1-1-1, except that the types of polymer raw materials and their amounts were changed (as shown in Table 2). Comparative Synthesis Examples of Polymer (A-1) Comparative Synthesis Examples A'-1-1 to A'-1-5

Comparative Synthesis Examples A'-1-1 to A'-1-5 were prepared by the same steps as Synthesis Example A-1-1-1, except that the types of polymer raw materials and their usage amounts were changed (as shown in Table 3).

The compounds corresponding to the numbers in Tables 1 to 3 are shown below. Abbreviation Element a1-1 2,3,5-tricarboxycyclopentylacetic acid dianhydride a1-2 1,2,3,4-cyclobutane tetracarboxylic acid dianhydride a1-3 Pyromellitic dianhydride b1-1-1 Formula (I-1) b1-1-2 Formula (I-2) b1-1-3 Formula (I-3) b1-1-4 Formula (I-6) b1-1-5 Formula (I-7) b1-1-6 Formula (I-9) b1-2-1 Formula (II-10) b1-2-2 Formula (II-18) b1-2-3 Formula (II-24) b1-2-4 Formula (II-22) b1-2-5 Formula (II-26) b1-3-1 Formula (III-1) b1-3-2 Formula (III-2) b1-3-3 Formula (III-3) b1-3-4 Formula (III-4) b1-3-5 Formula (III-5) b1-3-6 Formula (III-6) b1-4-1 p-diaminobenzene b1-4-2 2,2'-dimethyl-4,4'-diamino diphenyl b1-4-3 4,4'-methylenebis(cyclohexylamine) b1-4-4 1,4-diaminocyclohexane b1-4-5 3,3'-diaminochalcone b1-4-6 b1-4-7 b1-4-8 b1-4-9 Formula (2-1-1) a2-1 2,3,5-tricarboxycyclopentylacetic acid dianhydride a2-2 1,2,3,4-cyclobutane tetracarboxylic acid dianhydride a2-3 Pyromellitic dianhydride b2-1 p-diaminobenzene b2-2 2,2'-dimethyl-4,4'-diamino diphenyl b2-3 4,4'-methylenebis(cyclohexylamine) b2-4 1,4-diaminocyclohexane

Table 1 Ingredients (unit: mole%) Synthesis Example A-1-1-1 A-1-1-2 A-1-1-3 A-1-1-4 A-1-1-5 A-1-1-6 Tetracarboxylic dianhydride compound (a1) a1-1 100 100 a1-2 100 100 a1-3 100 100 Diamine compound (b1) Diamine compound (b1-1) b1-1-1 50 b1-1-2 60 b1-1-3 70 b1-1-4 80 b1-1-5 90 b1-1-6 100 Diamine compound (b1-2) b1-2-1 b1-2-2 b1-2-3 b1-2-4 b1-2-5 Diamine compound (b1-3) b1-3-1 b1-3-2 b1-3-3 b1-3-4 b1-3-5 b1-3-6 Other diamine compounds (b1-4) b1-4-1 50 30 b1-4-2 30 b1-4-3 20 b1-4-4 10 10 b1-4-5 b1-4-6 b1-4-7 b1-4-8 b1-4-9

Table 1 (continued) Ingredients (unit: mole%) Synthesis Example A-1-2-1 A-1-2-2 A-1-2-3 A-1-2-4 A-1-2-5 A-1-2-6 Tetracarboxylic dianhydride compound (a1) a1-1 a1-2 100 100 100 a1-3 100 100 100 Diamine compound (b1) Diamine compound (b1-1) b1-1-1 80 b1-1-2 70 b1-1-3 50 b1-1-4 60 b1-1-5 75 b1-1-6 65 Diamine compound (b1-2) b1-2-1 5 b1-2-2 10 b1-2-3 15 30 b1-2-4 20 b1-2-5 25 Diamine compound (b1-3) b1-3-1 b1-3-2 b1-3-3 b1-3-4 b1-3-5 b1-3-6 Other diamine compounds (b1-4) b1-4-1 20 25 10 b1-4-2 5 b1-4-3 30 b1-4-4 5 b1-4-5 b1-4-6 b1-4-7 b1-4-8 b1-4-9

Table 1 (continued) Ingredients (unit: mole%) Synthesis Example A-1-3-1 A-1-3-2 A-1-3-3 A-1-3-4 A-1-3-5 A-1-3-6 Tetracarboxylic dianhydride compound (a1) a1-1 100 100 100 a1-2 100 100 a1-3 100 Diamine compound (b1) Diamine compound (b1-1) b1-1-1 80 b1-1-2 85 b1-1-3 75 b1-1-4 60 b1-1-5 50 b1-1-6 60 Diamine compound (b1-2) b1-2-1 b1-2-2 b1-2-3 b1-2-4 b1-2-5 Diamine compound (b1-3) b1-3-1 1 b1-3-2 3 b1-3-3 5 b1-3-4 10 b1-3-5 15 b1-3-6 20 Other diamine compounds (b1-4) b1-4-1 14 40 b1-4-2 15 b1-4-3 25 b1-4-4 twenty two 20 b1-4-5 b1-4-6 b1-4-7 b1-4-8 b1-4-9

Table 1 (continued) Ingredients (unit: mole%) Synthesis Example A-1-4-1 A-1-4-2 A-1-4-3 A-1-4-4 A-1-4-5 A-1-4-6 Tetracarboxylic dianhydride compound (a1) a1-1 100 a1-2 100 100 100 a1-3 100 100 Diamine compound (b1) Diamine compound (b1-1) b1-1-1 80 b1-1-2 90 b1-1-3 70 b1-1-4 60 b1-1-5 50 b1-1-6 70 Diamine compound (b1-2) b1-2-1 10 b1-2-2 5 b1-2-3 30 b1-2-4 20 b1-2-5 25 10 Diamine compound (b1-3) b1-3-1 5 b1-3-2 10 b1-3-3 5 b1-3-4 20 b1-3-5 5 b1-3-6 10 Other diamine compounds (b1-4) b1-4-1 5 b1-4-2 10 b1-4-3 b1-4-4 10 b1-4-5 b1-4-6 b1-4-7 b1-4-8 b1-4-9

Table 2 Ingredients (unit: mole%) Synthesis Example A-2-1 A-2-2 A-2-3 A-2-4 A-2-5 A-2-6 Tetracarboxylic dianhydride compound (a2) a2-1 100 50 a2-2 100 100 100 a2-3 100 50 Diamine compound (b2) b2-1 100 70 10 b2-2 100 20 80 b2-3 100 90 b2-4 10 20

Table 3 Ingredients (unit: mole%) Comparative Synthesis Example A'-1-1 A'-1-2 A'-1-3 A'-1-4 A'-1-5 Tetracarboxylic dianhydride compound (a1) a1-1 100 100 a1-2 100 100 a1-3 100 Diamine compound (b1) Diamine compound (b1-1) b1-1-1 b1-1-2 b1-1-3 b1-1-4 b1-1-5 b1-1-6 Diamine compound (b1-2) b1-2-1 30 b1-2-2 b1-2-3 b1-2-4 b1-2-5 Diamine compound (b1-3) b1-3-1 20 b1-3-2 b1-3-3 b1-3-4 b1-3-5 b1-3-6 Other diamine compounds (b1-4) b1-4-1 50 b1-4-2 30 b1-4-3 b1-4-4 10 10 b1-4-5 50 b1-4-6 60 70 b1-4-7 70 b1-4-8 80 b1-4-9 20 Embodiments and comparative examples of liquid crystal alignment agent, liquid crystal alignment film and liquid crystal display element

The following describes Examples 1 to 36 and Comparative Examples 1 to 8 of a liquid crystal alignment agent, a liquid crystal alignment film, and a liquid crystal display element. Example 1 a. Liquid crystal alignment agent

100 parts by weight of the polymer (A-1-1-1) was added to 1200 parts by weight of N-methyl-2-pyrrolidone (B-1) and 800 parts by weight of ethylene glycol n-butyl ether (B-2), and stirred at room temperature until dissolved, thereby preparing the liquid crystal alignment agent of Example 1. b. Liquid crystal alignment film and liquid crystal display element

The above-mentioned liquid crystal alignment agent is applied to two glass substrates having a conductive film composed of ITO (indium-tin-oxide) by a printer (manufactured by Nippon Shashin Printing Co., Ltd., model S15-036) to form a pre-coating layer. After that, the glass substrate is placed on a heating plate and pre-baked at a temperature of 100°C for 5 minutes. Then, post-baking is performed in a circulation oven at a temperature of 220°C for 30 minutes. Finally, after the alignment treatment, a glass substrate with a liquid crystal alignment film of Example 1 formed thereon can be obtained.

Of the two glass substrates with liquid crystal alignment films formed thereon, one is coated with hot-press glue, and the other is sprinkled with a 4 μm spacer. Next, the two glass substrates are bonded together, and a pressure of 10 kg is applied by a hot press at a temperature of 150°C. Then, liquid crystal is injected using a liquid crystal injection machine (manufactured by Shimadzu Corporation, model ALIS-100X-CH). Next, the liquid crystal injection port is sealed with ultraviolet curing glue, and the ultraviolet curing glue is hardened by irradiating with ultraviolet light, and the liquid crystal is annealed in an oven at a temperature of 60°C for 30 minutes to obtain the liquid crystal display element of Example 1.

The liquid crystal display element of Example 1 was evaluated by the evaluation methods described below, and the results are shown in Table 4 .

The liquid crystal alignment agents, liquid crystal alignment films and liquid crystal display devices of Examples 2 to 36 were prepared in the same steps as Example 1, except that the types and amounts of components were changed, as shown in Table 4. The liquid crystal display devices prepared in Examples 2 to 36 were evaluated by the evaluation method described below, and the results are shown in Table 4. Comparative Examples 1 to 8

The liquid crystal alignment agents, liquid crystal alignment films and liquid crystal display elements of Comparative Examples 1 to 8 were prepared respectively in the same steps as Example 1, except that the types and amounts of components were changed, as shown in Table 5. The liquid crystal display elements prepared in Comparative Examples 1 to 8 were evaluated in the evaluation method described below, and the results are shown in Table 5.

The compounds corresponding to the numbers in Table 4 and Table 5 are shown below. Abbreviation Element A-1-1-1 Polymer A-1-1-1 A-1-1-2 Polymer A-1-1-2 A-1-1-3 Polymer A-1-1-3 A-1-1-4 Polymer A-1-1-4 A-1-1-5 Polymer A-1-1-5 A-1-1-6 Polymer A-1-1-6 A-1-2-1 Polymer A-1-2-1 A-1-2-2 Polymer A-1-2-2 A-1-2-3 Polymer A-1-2-3 A-1-2-4 Polymer A-1-2-4 A-1-2-5 Polymer A-1-2-5 A-1-2-6 Polymer A-1-2-6 A-1-3-1 Polymer A-1-3-1 A-1-3-2 Polymer A-1-3-2 A-1-3-3 Polymer A-1-3-3 A-1-3-4 Polymer A-1-3-4 A-1-3-5 Polymer A-1-3-5 A-1-3-6 Polymer A-1-3-6 A-1-4-1 Polymer A-1-4-1 A-1-4-2 Polymer A-1-4-2 A-1-4-3 Polymer A-1-4-3 A-1-4-4 Polymer A-1-4-4 A-1-4-5 Polymer A-1-4-5 A-1-4-6 Polymer A-1-4-6 A'-1-1 Polymer A'-1-1 A'-1-2 Polymer A'-1-2 A'-1-3 Polymer A'-1-3 A'-1-4 Polymer A'-1-4 A'-1-5 Polymer A'-1-5 A-2-1 Polymer A-2-1 A-2-2 Polymer A-2-2 A-2-3 Polymer A-2-3 A-2-4 Polymer A-2-4 A-2-5 Polymer A-2-5 A-2-6 Polymer A-2-6 B-1 N-methyl-2-pyrrolidone (NMP) B-2 Ethylene glycol n-butyl ether B-3 N,N-dimethylacetamide C-1 N,N,N',N'-tetraepoxypropyl-4,4'-diaminodiphenyl methane C-2 N,N-epoxypropyl-p-glycidoxyaniline Evaluation method > Electric field memory effect >

The liquid crystal display elements of Examples 1 to 36 and Comparative Examples 1 to 8 were evaluated using a liquid crystal evaluation device (manufactured by CHUO PRECISION INDUSTRIAL CO., LTD., model OMS-CM4RD) according to the method described in " T. J. Scheffer, et.al., J. Appl. Phys., vol. 19, 2013 (1980) ." Specifically, the pre-tilt angle was measured using the crystal rotation method of He-Ne laser light and recorded as P _m . Then, an alternating current of 60 Hz and 16 volts was applied and placed on a light-emitting diode (LED) backlight source. After 36 hours, the pre-tilt angle was measured again and recorded as P _n . The change in pre-tilt angle was calculated using the following formula. The smaller the change in pre-tilt angle, the better the electric field memory effect of the liquid crystal display element. Conversely, the larger the change in pre-tilt angle, the worse the electric field memory effect of the liquid crystal display element, and may even cause the problem of being unable to perform photo-alignment. Pre-tilt angle change = | _Pm - _Pn |

The evaluation criteria for pre-tilt angle change are as follows: ◎: Pre-tilt angle change ≤ 0.3°; ○: 0.3°＜Pre-tilt angle change ≤ 0.6°; △: 0.6°＜Pre-tilt angle change ≤ 1.0°; ╳: 1.0°＜Pre-tilt angle change, or photo-alignment cannot be performed. > Environmental Resistance >

The liquid crystal display elements of Examples 1 to 36 and Comparative Examples 1 to 8 were placed in an environment with a temperature of 65°C and a relative humidity of 85%. After 120 hours, the ion density of the liquid crystal display elements of Examples 1 to 36 and Comparative Examples 1 to 8 was measured using an electrical measuring machine (manufactured by Dongyang Company, Model 6254). The test conditions were to apply a 1.7 volt voltage and a 0.01 Hz triangle wave at a temperature of 60°C. In the current-voltage waveform, the peak area in the range of 0 volts to 1 volt was calculated to measure the ion density (pC). The lower the ion density, the better the environmental resistance. Conversely, the higher the ion density, the worse the environmental resistance.

The evaluation criteria for ion density are as follows: ◎: ion density <20; ○: 20≦ ion density <40; △: 40≦ ion density <50; ╳: 50≦ ion density.

Table 4 Ingredients (unit: weight parts) Embodiment 1 2 3 4 5 6 7 8 9 10 11 12 Polymer (A-1) A-1-1-1 100 30 A-1-1-2 100 40 A-1-1-3 100 50 A-1-1-4 100 70 A-1-1-5 100 90 A-1-1-6 100 95 A-1-2-1 A-1-2-2 A-1-2-3 A-1-2-4 A-1-2-5 A-1-2-6 A-1-3-1 A-1-3-2 A-1-3-3 A-1-3-4 A-1-3-5 A-1-3-6 A-1-4-1 A-1-4-2 A-1-4-3 A-1-4-4 A-1-4-5 A-1-4-6 A'-1-1 A'-1-2 A'-1-3 A'-1-4 A'-1-5 Polymer (A-2) A-2-1 70 A-2-2 60 A-2-3 50 A-2-4 30 A-2-5 10 A-2-6 5 Solvent (B) B-1 1200 800 1000 900 850 1500 800 B-2 800 1000 800 1500 300 850 2000 1000 750 B-3 1000 800 100 600 300 500 1500 Additive(C) C-1 C-2 Evaluation results Electric field memory effect ○ ○ ○ ○ ○ ○ ◎ ◎ ◎ ◎ ◎ ◎ Environmental resistance ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

Table 4 (continued) Ingredients (unit: weight parts) Embodiment 13 14 15 16 17 18 19 20 twenty one twenty two twenty three twenty four Polymer (A-1) A-1-1-1 A-1-1-2 A-1-1-3 A-1-1-4 A-1-1-5 A-1-1-6 A-1-2-1 100 A-1-2-2 100 A-1-2-3 100 A-1-2-4 100 A-1-2-5 100 A-1-2-6 100 A-1-3-1 100 A-1-3-2 100 A-1-3-3 100 A-1-3-4 100 A-1-3-5 100 A-1-3-6 100 A-1-4-1 A-1-4-2 A-1-4-3 A-1-4-4 A-1-4-5 A-1-4-6 A'-1-1 A'-1-2 A'-1-3 A'-1-4 A'-1-5 Polymer (A-2) A-2-1 A-2-2 A-2-3 A-2-4 A-2-5 A-2-6 Solvent (B) B-1 1000 1200 800 1000 1000 1500 B-2 1000 600 1000 800 1500 300 1000 2000 1000 B-3 1000 800 100 600 500 1000 350 1500 Additive(C) C-1 C-2 Evaluation results Electric field memory effect ◎ ◎ ◎ ◎ ◎ ◎ ○ ○ ○ ○ ○ ○ Environmental resistance ○ ○ ○ ○ ○ ○ ◎ ◎ ◎ ◎ ◎ ◎

Table 4 (continued) Ingredients (unit: weight parts) Embodiment 25 26 27 28 29 30 31 32 33 34 35 36 Polymer (A-1) A-1-1-1 A-1-1-2 A-1-1-3 A-1-1-4 A-1-1-5 A-1-1-6 A-1-2-1 30 A-1-2-2 40 A-1-2-3 A-1-2-4 A-1-2-5 A-1-2-6 A-1-3-1 A-1-3-2 A-1-3-3 60 A-1-3-4 70 A-1-3-5 A-1-3-6 A-1-4-1 100 A-1-4-2 100 A-1-4-3 100 A-1-4-4 100 A-1-4-5 100 95 A-1-4-6 100 90 A'-1-1 A'-1-2 A'-1-3 A'-1-4 A'-1-5 Polymer (A-2) A-2-1 70 5 A-2-2 30 A-2-3 A-2-4 40 A-2-5 60 A-2-6 10 Solvent (B) B-1 800 1000 1200 800 1000 1000 1500 1500 B-2 750 1000 600 1000 800 1500 300 2000 1000 B-3 1000 800 100 600 300 350 Additive(C) C-1 3 2 C-2 1 3 Evaluation results Electric field memory effect ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ Environmental resistance ◎ ◎ ◎ ◎ ◎ ◎ ○ ○ ◎ ◎ ◎ ◎

Table 5 Ingredients (unit: weight parts) Comparison Example 1 2 3 4 5 6 7 8 Polymer (A-1) A-1-1-1 A-1-1-2 A-1-1-3 A-1-1-4 A-1-1-5 A-1-1-6 A-1-2-1 A-1-2-2 A-1-2-3 A-1-2-4 A-1-2-5 A-1-2-6 A-1-3-1 A-1-3-2 A-1-3-3 A-1-3-4 A-1-3-5 A-1-3-6 A-1-4-1 A-1-4-2 A-1-4-3 A-1-4-4 A-1-4-5 A-1-4-6 A'-1-1 100 A'-1-2 100 50 A'-1-3 100 70 A'-1-4 100 80 A'-1-5 100 Polymer (A-2) A-2-1 50 A-2-2 30 A-2-3 20 A-2-4 A-2-5 A-2-6 Solvent (B) B-1 1000 1200 800 1000 1000 B-2 1000 600 1000 800 1500 300 B-3 1000 800 100 600 500 Additive(C) C-1 C-2 Evaluation results Electric field memory effect ╳ ╳ ╳ ╳ ╳ ╳ ╳ ╳ Environmental resistance ╳ ╳ ╳ ╳ ╳ ╳ ╳ ╳ > Evaluation Results >

As can be seen from Tables 4 and 5, the liquid crystal alignment film and the liquid crystal display element formed by the liquid crystal alignment agent using the diamine compound (b1-1) (Examples 1 to 36) have good electric field memory effect and environmental resistance compared to the liquid crystal alignment agent without the diamine compound (b1-1) (Comparative Examples 1 to 8). In other words, the liquid crystal alignment film and the liquid crystal display element formed by the liquid crystal alignment agent without the diamine compound (b1-1) (Comparative Examples 1 to 8) have the problem of poor electric field memory effect and environmental resistance.

When the usage amount of the polymer (A-1) in the liquid crystal alignment agent is within the range of 30 parts by weight to 95 parts by weight (Examples 7 to 12), the liquid crystal alignment film and liquid crystal display element formed by the liquid crystal alignment agent can have a better electric field memory effect.

When the diamine compound (b1) in the polymer (A-1) in the liquid crystal alignment agent includes the diamine compound (b1-2) (Examples 13 to 18, 31 and 32), the liquid crystal alignment film and liquid crystal display element formed by the liquid crystal alignment agent can have a better electric field memory effect.

When the diamine compound (b1) in the polymer (A-1) in the liquid crystal alignment agent includes the diamine compound (b1-3) (Examples 19 to 24, 33 and 34), the liquid crystal alignment film and liquid crystal display element formed by the liquid crystal alignment agent can have better environmental resistance.

When the diamine compound (b1) in the polymer (A-1) in the liquid crystal alignment agent includes a diamine compound (b1-2) and a diamine compound (b1-3) (Examples 25 to 30, 35 and 36), the liquid crystal alignment film and liquid crystal display element formed by the liquid crystal alignment agent can have better electric field memory effect and better environmental resistance.

In summary, the polymer in the liquid crystal alignment agent of the present invention is prepared by reacting a tetracarboxylic dianhydride compound and a diamine compound having a specific structure. Therefore, when the liquid crystal alignment agent is used to form a liquid crystal alignment film, the liquid crystal display element using the liquid crystal alignment film has good electric field memory effect and environmental resistance, and is therefore suitable for liquid crystal alignment films and liquid crystal display elements.

Although the present invention has been disclosed as above by the embodiments, they are not intended to limit the present invention. Any person with ordinary knowledge in the relevant technical field can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be defined by the scope of the attached patent application.

100: Liquid crystal display element 110: First unit 112: First substrate 114: First conductive film 116: First liquid crystal alignment film 120: Second unit 122: Second substrate 124: Second conductive film 126: Second liquid crystal alignment film 130: Liquid crystal unit

FIG. 1 is a side view of a liquid crystal display element according to an embodiment of the present invention.

100: Liquid crystal display element

110: Unit 1

112: first substrate

114: first conductive film

116: first liquid crystal alignment film

120: Unit 2

122: Second substrate

124: Second conductive film

126: second liquid crystal alignment film

130: Liquid crystal unit

Claims (17)

A diamine compound, which is a diamine compound (b1-1) represented by formula (I):

In formula (I), ^X1 and ^X2 each independently represent a single bond, -O-,

,

,

or

, wherein R ¹⁴ represents hydrogen or an alkyl group having 1 to 4 carbon atoms; x represents 0 or 1; y represents an integer from 0 to 4; R ¹ represents a methylene group or an alkylene group having 2 to 4 carbon atoms; R ³ each independently represents an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a halogen atom or a cyano group; R ² represents an organic group represented by formula (IA) or a monovalent organic group having a steroid skeleton and having 17 to 40 carbon atoms;

In formula (IA), R ⁴ represents fluorine or methyl; R ⁵ , R ⁶ and R ⁷ each independently represent a single bond, -O-,

,

,

,

,

, methylene or alkylene having 2 to 3 carbon atoms; R ⁸ represents

or

, wherein R ¹⁰ and R ¹¹ each independently represent fluorine or methyl, * represents a bonding position; R ⁹ represents hydrogen, fluorine, an alkyl group having 1 to 12 carbon atoms, a fluoroalkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms substituted with fluorine, -OCH ₂ F, -OCHF ₂ , -OCF ₃ ; a represents an integer from 0 to 2; b, c and d each independently represent an integer from 0 to 4; e, f and g each independently represent an integer from 0 to 3; i and j each independently represent an integer from 0 to 2; * represents a bonding position; when R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ¹⁰ or R ¹¹ is plural, each independently represents the same or different groups, When e+f+g<3, f and g are not 0 at the same time; when f≧1, b≧1; when g≧1, c+d≧1. The diamine compound as described in item 1 of the patent application, wherein in the diamine compound (b1-1) represented by formula (I), when x is 0, ^X1 is -O-,

,

,

,

,

,

,

,

,

or

, wherein R ¹⁴ represents hydrogen or an alkyl group having 1 to 4 carbon atoms; when x is 1, X ¹ is a single bond. The diamine compound as described in item 1 of the patent application, wherein in the diamine compound (b1-1) represented by formula (I), when x is 0, ^X1 is -O-,

,

,

or

The diamine compound as described in claim 1, wherein in the diamine compound (b1-1) represented by formula (I), R ⁵ , R ⁶ and R ⁷ each independently represent a single bond, -O-,

,

,

, methylene or an alkylene group having 2 to 3 carbon atoms. A polymer (A-1) is prepared by reacting a first mixture, wherein the first mixture comprises a tetracarboxylic dianhydride compound (a1) and a diamine compound (b1), wherein the diamine compound (b1) comprises a diamine compound (b1-1) represented by formula (I) as described in any one of items 1 to 4 of the scope of the application. The polymer (A-1) as described in claim 5, wherein the diamine compound (b1) further comprises a diamine compound (b1-2) represented by formula (II):

In formula (II), R ¹⁵ and R ¹⁷ each independently represent -O-, -S-,

,

,

or

; R ¹⁶ represents an alkylene group having 2 to 10 carbon atoms; R ¹⁸ represents a single bond, a methylene group or an ethylene group; Y ¹ represents a monovalent organic group having 17 to 40 carbon atoms and a steroid skeleton. The polymer (A-1) as described in claim 5, wherein the diamine compound (b1) further comprises a diamine compound (b1-3) represented by formula (III):

In formula (III), ^Y2 each independently represents -O-, -NH-,

,

,

、-CH ₂ O-、

,

or

; Y ³ each independently represents a single bond, a divalent aliphatic hydrocarbon group having 1 to 20 carbon atoms, a divalent alicyclic hydrocarbon group, or a divalent aromatic hydrocarbon group; Y ⁴ each independently represents a single bond, -O-, -NH-,

,

,

,

,

,

,

or

, wherein m represents an integer from 1 to 5; Y ⁵ each independently represents a nitrogen-containing aromatic heterocyclic group; and k represents an integer from 1 to 4. The polymer (A-1) as described in item 5 of the patent application, wherein the amount of the diamine compound (b1-1) represented by formula (I) is 50 to 100 mol parts based on 100 mol parts of the diamine compound (b1). The polymer (A-1) as described in item 6 of the patent application, wherein the amount of the diamine compound (b1) used is 100 mol parts, and the amount of the diamine compound (b1-2) represented by formula (II) used is 5 mol parts to 30 mol parts. The polymer (A-1) as described in item 7 of the patent application, wherein the amount of the diamine compound (b1) used is 100 mol parts, and the amount of the diamine compound (b1-3) represented by formula (III) used is 1 mol part to 20 mol parts. A liquid crystal alignment agent, comprising a polymer (A-1) as described in any one of items 5 to 10 of the patent application scope and a solvent (B). The liquid crystal alignment agent as described in item 11 of the patent application further includes a polymer (A-2), wherein the polymer (A-2) is prepared by reacting a second mixture, and the second mixture includes a tetracarboxylic dianhydride compound (a2) and a diamine compound (b2). As described in item 11 of the patent application, the amount of the liquid crystal alignment agent is 100 parts by weight based on the amount of the polymer (A-1) used being 100 parts by weight, and the amount of the solvent (B) used being 1000 parts by weight to 3500 parts by weight. As described in item 12 of the patent application, the liquid crystal alignment agent, wherein the total amount of the polymer (A-1) and the polymer (A-2) used is 100 parts by weight, and the amount of the polymer (A-1) used is 30 parts by weight to 95 parts by weight. As described in item 12 of the patent application, the liquid crystal alignment agent, based on the total usage of the polymer (A-1) and the polymer (A-2) being 100 parts by weight, the usage of the solvent (B) is 1000 parts by weight to 3500 parts by weight. A liquid crystal alignment film, which is formed by a liquid crystal alignment agent as described in any one of items 11 to 15 of the patent application scope. A liquid crystal display element, comprising a liquid crystal alignment film as described in item 16 of the patent application scope.

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