CN106010583B - Liquid crystal alignment agent, liquid crystal alignment film and liquid crystal display assembly - Google Patents

Abstract

The invention provides a liquid crystal alignment agent, a liquid crystal alignment film and a liquid crystal display assembly. The liquid crystal aligning agent comprises a polymer (A) and a solvent (B). The polymer (A) is obtained by reacting a mixture comprising a tetracarboxylic dianhydride component (a) and a diamine component (b). Tetracarboxylic dianhydride component (a)Comprising a tetracarboxylic dianhydride compound (a-1) represented by the formula (1). The diamine component (b) includes a diamine compound (b-1) represented by formula (2). The invention can improve the ultraviolet reliability of the liquid crystal alignment film.

Description

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

technical field

The present invention relates to a liquid crystal alignment agent, a liquid crystal alignment film and a liquid crystal display component, in particular to a liquid crystal alignment agent capable of forming a liquid crystal alignment film with good ultraviolet reliability, a liquid crystal alignment film formed by the liquid crystal alignment agent and A liquid crystal display component having the above-mentioned liquid crystal alignment film.

Background technique

In recent years, due to the increasing demands of consumers on the wide viewing angle characteristics of liquid crystal displays year by year, the requirements on the electrical characteristics or display characteristics of wide viewing angle liquid crystal display components have become more stringent than before. Among the wide viewing angle liquid crystal display components, vertical alignment liquid crystal display components are most commonly studied. Therefore, in order to have better electrical properties and display properties, liquid crystal alignment films have become one of the important research objects to improve the properties of vertical alignment liquid crystal display components, especially after large-scale liquid crystal TVs are widely used. For displays that mainly display text or still images, it is even more necessary to maintain reliability for long-term use.

Japanese Patent Application Laid-Open No. 9-176651 discloses a liquid crystal alignment film with a high pretilt angle. The tetracarboxylic dianhydride compound containing a steroid skeleton and the diamine compound containing a steroid skeleton are used in the liquid crystal alignment film at the same time, so that the liquid crystal alignment film can still maintain a high pretilt angle after the reliability test. However, the liquid crystal alignment film has the problem of poor UV reliability. Specifically, after the liquid crystal alignment film is irradiated with ultraviolet rays for a period of time, the voltage retention rate of the liquid crystal display will drop significantly, which in turn will cause problems such as a decrease in the contrast of the liquid crystal display.

Therefore, how to provide a liquid crystal alignment agent capable of forming a liquid crystal alignment film with good ultraviolet reliability, so that when the liquid crystal alignment film formed is applied to a liquid crystal display module, it can still maintain a high voltage retention rate under long-term ultraviolet irradiation , is actually a problem that those skilled in the art want to solve urgently.

Contents of the invention

In view of this, the present invention provides a liquid crystal alignment agent, a liquid crystal alignment film and a liquid crystal display component, so as to improve the ultraviolet reliability of the liquid crystal alignment film.

The present invention provides a liquid crystal alignment agent, which includes a polymer (A) and a solvent (B). The polymer (A) is obtained by reacting a mixture including a tetracarboxylic dianhydride component (a) and a diamine component (b). The tetracarboxylic dianhydride component (a) includes a tetracarboxylic dianhydride compound (a-1) represented by formula (1). The diamine component (b) includes a diamine compound (b-1) represented by formula (2).

Specifically, the tetracarboxylic dianhydride compound (a-1) represented by formula (1) is as follows.

In formula (1), P ¹ , P ² , P ³ and P ⁴ each independently represent a single bond or a methylene group; j represents an integer of 1 to 3.

In addition, the diamine compound (b-1) represented by formula (2) is as follows.

In formula (2), Y ¹ represents an alkylene group having a carbon number of 1 to 12; Y ² represents a group having a steroid skeleton or a group represented by formula (2-1), wherein, represented by formula (2-1) The basis for is as follows.

In formula (2-1), R ¹ each independently represents a fluorine atom or a methyl group; R ² represents a hydrogen atom, a fluorine atom, an alkyl group with 1 to 12 carbons, a fluoroalkyl group with 1 to 12 carbons, a carbon Alkoxy group with a number of 1 to 12, -OCH ₂ F, -OCHF ₂ or -OCF ₃ ; Z ¹ , Z ² and Z ³ each independently represent a single bond, an alkylene group with a carbon number of 1 to 3, -O -, Z ⁴ are independently indicated R ^a and R ^b each independently represent a fluorine atom or a methyl group, h and i each independently represent 0, 1 or 2; a represents 0, 1 or 2; b, c and d each independently represent an integer from 0 to 4; e, f and g each independently represent an integer of 0 to 3, and e+f+g≧1.

In one embodiment of the present invention, based on the total number of moles of the tetracarboxylic dianhydride component (a) being 100, the amount of the tetracarboxylic dianhydride compound (a-1) used is 5 to 50 moles.

In one embodiment of the present invention, based on the total moles of the diamine component (b) being 100 moles, the amount of the diamine compound (b-1) used is 3 to 20 moles.

In an embodiment of the present invention, the imidization rate of the above-mentioned polymer (A) is 30% to 90%.

The present invention further provides a liquid crystal alignment film formed from the above-mentioned liquid crystal alignment agent.

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

Based on the above, the liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display assembly of the present invention have good ultraviolet reliability of the liquid crystal alignment film formed by the liquid crystal alignment agent, and are suitable for liquid crystal display assemblies.

In order to make the above-mentioned features and advantages of the present invention more comprehensible, the following specific embodiments are described in detail with reference to the accompanying drawings.

Description of drawings

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

Explanation of reference signs:

100: liquid crystal display component;

110: first unit;

112: the first substrate;

114: the first conductive film;

116: a first liquid crystal alignment film;

120: second unit;

122: a second substrate;

124: the second conductive film;

126: a second liquid crystal alignment film;

130: a liquid crystal unit.

Detailed ways

<Liquid crystal alignment agent>

The present invention provides a liquid crystal alignment agent, which includes a polymer (A) and a solvent (B). In addition, the liquid crystal alignment agent may further include an additive (C) if necessary.

Each component of the liquid crystal alignment agent used in the present invention will be described in detail below.

It is explained here that (meth)acrylic acid is used to represent acrylic acid and/or methacrylic acid, and (meth)acrylate is used to represent acrylate and/or methacrylate; similarly, (meth) Acryloyl means acryloyl and/or methacryloyl.

Polymer (A)

The polymer (A) is obtained by reacting a mixture including a tetracarboxylic dianhydride component (a) and a diamine component (b).

Specifically, the polymer (A) includes polyamic acid, polyimide, polyamic acid-polyimide block copolymer, or a combination of these polymers. Wherein, the polyimide series block copolymer comprises polyamic acid block copolymer, polyimide block copolymer, polyamic acid-polyimide block copolymer or the polyamic acid block copolymer combination. Polyamic acid polymers, polyimide polymers and polyamic acid-polyimide block copolymers can all be formed by the mixture reaction of tetracarboxylic dianhydride component (a) and diamine component (b). be made of.

Tetracarboxylic dianhydride component (a)

The tetracarboxylic dianhydride component (a) includes a tetracarboxylic dianhydride compound (a-1) and a tetracarboxylic dianhydride compound (a-2).

Tetracarboxylic dianhydride compound (a-1)

Tetracarboxylic dianhydride compound (a-1) is a compound represented by formula (1).

In formula (1), P ¹ , P ² , P ³ and P ⁴ each independently represent a single bond or a methylene group; j represents an integer of 1 to 3. In formula (1), j preferably represents 1 to 2, and more preferably represents 1.

In the tetracarboxylic dianhydride compound (a-1) represented by formula (1), specific examples where j represents 1 include but are not limited to bicyclo[3.3.0]octane-2,4,6,8-tetracarboxylic acid Dianhydride (compound represented by formula (1-1)), bicyclo[4.3.0]nonane-2,4,7,9-tetracarboxylic dianhydride (compound represented by formula (1-2)), Bicyclo[4.4.0]decane-2,4,8,10-tetracarboxylic dianhydride (compound represented by formula (1-3)), bicyclo[4.4.0]decane-2,4,7, 9-tetracarboxylic dianhydride (compound represented by formula (1-4)), or a combination thereof.

In addition, in the tetracarboxylic dianhydride compound (a-1) represented by formula (1), specific examples where j represents 2 include, but are not limited to, tricyclo[6.3.0.0 ^2,6 ]undecane-3,5, 9,11-tetracarboxylic dianhydride (compound represented by formula (1-5)).

Specific examples of the tetracarboxylic dianhydride compound (a-1) represented by the formula (1) preferably include bicyclo[3.3.0]octane-2,4,6,8-tetracarboxylic dianhydride (formulated by the formula (1-1) represented), bicyclo[4.3.0]nonane-2,4,7,9-tetracarboxylic dianhydride (compound represented by formula (1-2)), tricyclo[6.3. 0.0 ^2,6 ] Undecane-3,5,9,11-tetracarboxylic dianhydride (compound represented by formula (1-5)), or a combination thereof.

The tetracarboxylic dianhydride compound (a-1) may have an isomer structure, and either one type of isomer or a mixture of isomers may be used. Taking bicyclo[3.3.0]octane-2,4,6,8-tetracarboxylic dianhydride as an example, it can have the following formula (1-1-a), formula (1-1-b) or formula ( The structure shown in 1-1-c).

Bicyclo[3.3.0]octane-2,4,6,8-tetracarboxylic dianhydride can be synthesized, for example, by the following method. First, 2,5-norbornadiene (2,5-norbornadiene) and dicyclopentadiene (dicyclopentadiene) were reacted in an autoclave at a temperature of 190°C for 20 hours to form tetracyclic [6.2.1.1 ^3,6 .0 ^2,7 ]Dodeca-4,9-diene. Next, the resulting compound was subjected to an ozonolysis reaction (Ozonolysis) in methanol at -30°C, and then oxidatively decomposed using hydrogen peroxide in a mixed solvent of formic acid and acetic acid to form a bicyclic [3.3.0] Octane-2,4,6,8-tetracarboxylic acid (Bicyclo[3.3.0]octane-2,4,6,8-tetracarboxylic acid, BOTA for short). Add BOTA to acetic anhydride and heat treatment to obtain bicyclo[3.3.0]octane-2,4,6,8-tetracarboxylic dianhydride. In addition, BOTA can also be formed by oxidizing tetracyclo[6.2.1.1 ^3,6 .0 ^2,7 ]dodeca-4,9-diene with potassium permanganate.

Based on the total amount of tetracarboxylic dianhydride component (a) used as 100 moles, the amount of tetracarboxylic dianhydride compound (a-1) used can be from 5 moles to 50 moles, preferably from 8 moles to 45 moles, More preferably, it is 10 mol to 40 mol. When the liquid crystal alignment agent does not use the tetracarboxylic dianhydride compound (a-1), the liquid crystal alignment film has the problem of poor UV reliability.

Tetracarboxylic dianhydride compound (a-2)

Tetracarboxylic dianhydride compound (a-2) comprises aliphatic tetracarboxylic dianhydride compound, alicyclic tetracarboxylic dianhydride compound, aromatic tetracarboxylic dianhydride compound, by formula (I-1) to formula ( At least one of the tetracarboxylic dianhydride compounds represented by I-6), or a combination of the above-mentioned compounds.

Although the specific example of an aliphatic tetracarboxylic dianhydride compound, an alicyclic tetracarboxylic dianhydride compound, and an aromatic tetracarboxylic dianhydride compound is mentioned below, this invention is not limited to these specific examples.

Specific examples of the aliphatic tetracarboxylic dianhydride compound may include, but are not limited to, ethanetetracarboxylic dianhydride, butane tetracarboxylic dianhydride, or combinations of the above compounds.

Specific examples of alicyclic tetracarboxylic dianhydride compounds may include, but are not limited to, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2-dimethyl-1,2,3,4- Cyclobutane tetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,3-dichloro-1,2,3,4-cyclobutane Butane tetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2,3,4-cyclopentane tetracarboxylic Acid dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3',4,4'-dicyclohexyltetracarboxylic dianhydride, cis-3,7-dibutylcycloheptane 1,5-diene-1,2,5,6-tetracarboxylic dianhydride or 2,3,5-tricarboxycyclopentylacetic dianhydride or a combination of the above compounds.

Specific examples of aromatic tetracarboxylic dianhydride compounds may include, but are not limited to, 3,4-dicarboxy-1,2,3,4-tetrahydronaphthalene-1-succinic dianhydride, pyromellitic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-biphenylsulfone tetracarboxylic dianhydride, 1,4,5,8-naphthalene tetracarboxylic Acid dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 3,3'-4,4'-diphenylethanetetracarboxylic dianhydride, 3,3',4,4'- Dimethyldiphenylsilane tetracarboxylic dianhydride, 3,3',4,4'-tetraphenylsilane tetracarboxylic dianhydride, 1,2,3,4-furan tetracarboxylic dianhydride, 4, 4'-bis(3,4-dicarboxyphenoxy)diphenylsulfide dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenylsulfone dianhydride, 4,4'- Bis(3,4-dicarboxyphenoxy)diphenylpropane dianhydride (4,4'-bis(3,4-dicarboxyphenoxy)diphenylpropane dianhydride), 3,3',4,4'-perfluoroiso Propyl diphthalic dianhydride, 3,3',4,4'-diphenyltetracarboxylic dianhydride, bis(phthalic acid)phenylphosphine oxide dianhydride, p-phenylene-bis(tri Phenylphthalic acid) dianhydride, m-phenylene-bis(triphenylphthalic acid) dianhydride, bis(triphenylphthalic acid)-4,4'-diphenylether dianhydride, bis (Triphenylphthalic acid)-4,4'-diphenylmethane dianhydride, ethylene glycol-bis(anhydrotrimellitate), propylene glycol-bis(anhydrotrimellitate), 1,4 -Butanediol-bis(anhydrotrimellitate), 1,6-Hexanediol-bis(anhydrotrimellitate), 1,8-octanediol-bis(anhydrotrimellitate) , 2,2-bis(4-hydroxyphenyl)propane-bis(dehydrated trimellitate), 2,3,4,5-tetrahydrofuran tetracarboxylic dianhydride, 1,3,3a,4,5, 9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furyl)-naphtho[1,2-c]-furan-1,3-dione {(1,3, 3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)naphtho[1,2-c]furan-1,3-dione)}, 1,3,3a,4 ,5,9b-Hexahydro-5-methyl-5-(tetrahydro-2,5-dioxo-3-furyl)-naphtho[1,2-c]-furan-1,3- Diketone, 1,3,3a,4,5,9b-hexahydro-5-ethyl-5-(tetrahydro-2,5-dipentoxy-3-furyl)-naphtho[1,2 -c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-7-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, 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-8-ethyl-5-(tetra Hydrogen-2,5-dioxo-3-furyl)-naphtho[1,2-c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro -5,8-Dimethyl-5-(tetrahydro-2,5-dioxo-3-furyl)-naphtho[1,2-c]-furan-1,3-dione, 5 -Aromatic tetracarboxylic dianhydride compounds such as (2,5-dipentoxytetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic dianhydride or combinations of the above-mentioned compounds.

The tetracarboxylic dianhydride compounds represented by formula (I-1) to formula (I-6) are shown below.

In formula (I-5), A ¹ represents a divalent group containing an aromatic ring; r represents an integer from 1 to 2; A ² and A ³ may be the same or different, and may each independently represent a hydrogen atom or an alkyl group. Specific examples of the tetracarboxylic dianhydride compound represented by formula (I-5) include at least one of the compounds represented by formula (I-5-1) to formula (I-5-3).

In formula (I-6), A ⁴ represents a divalent group containing an aromatic ring; A ⁵ and A ⁶ may be the same or different, and each independently represents a hydrogen atom or an alkyl group. The tetracarboxylic dianhydride compound represented by formula (I-6) is preferably a compound represented by formula (I-6-1).

The tetracarboxylic dianhydride compound (a-2) can be used individually or in combination of multiple types.

Specific examples of the tetracarboxylic dianhydride compound (a-2) preferably include 1,2,3,4-cyclobutane tetracarboxylic dianhydride (1,2,3,4-cyclobutane tetracarboxylic dianhydride), 1, 2,3,4-cyclopentanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride (2,3,5-tricarboxycyclopentylacetic dianhydride), 1,2,4,5-cyclohexyl Alkanetetracarboxylic dianhydride, 3,4-dicarboxy-1,2,3,4-tetrahydronaphthalene-1-succinic dianhydride, pyromellitic dianhydride, 3,3', 4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-biphenyl sulfone tetracarboxylic dianhydride, a compound represented by formula (I-1), or a combination of these compounds.

Based on the total number of moles of the tetracarboxylic dianhydride component (a) being 100 moles, the amount of the tetracarboxylic dianhydride compound (a-2) can be from 50 moles to 95 moles, preferably from 55 moles to 92 moles, And more preferably from 60 mol to 90 mol.

Based on 100 moles of the total moles of the diamine component (b), the tetracarboxylic dianhydride component (a) is preferably used in an amount ranging from 20 moles to 200 moles, more preferably from 30 moles to 120 moles.

Diamine component (b)

The diamine component (b) includes a diamine compound (b-1) and a diamine compound (b-2).

Diamine compound (b-1)

The diamine compound (b-1) is a compound represented by formula (2).

In formula (2), Y ¹ represents an alkylene group having a carbon number of 1 to 12; Y ² represents a group having a steroid (cholesterol, steroid) skeleton or a group represented by formula (2-1).

The group represented by formula (2-1) is as follows.

In formula (2-1), R ¹ each independently represents a fluorine atom or a methyl group; R ² represents a hydrogen atom, a fluorine atom, an alkyl group with 1 to 12 carbons, a fluoroalkyl group with 1 to 12 carbons, a carbon Alkoxy group with a number of 1 to 12, -OCH ₂ F, -OCHF ₂ or -OCF ₃ ; Z ¹ , Z ² and Z ³ each independently represent a single bond, an alkylene group with a carbon number of 1 to 3, -O -, Z ⁴ are independently indicated R ^a and R ^b each independently represent a fluorine atom or a methyl group, h and i each independently represent 0, 1 or 2; a represents 0, 1 or 2; b, c and d each independently represent an integer from 0 to 4; e, f and g each independently represent an integer of 0 to 3, and e+f+g≧1.

Specific examples of the diamine compound (b-1) include at least one of the compounds represented by formula (2-2) to formula (2-19).

The diamine compound (b-1) can be produced by a general organic synthesis method. For example, the compounds represented by formula (2-2) to formula (2-19) can be added maleic anhydride on the compound having steroid skeleton or by the compound represented by formula (2-20) respectively, In the presence of potassium, a dinitrobenzoyl chloride compound is added for esterification. Then, a suitable reducing agent such as tin chloride is added to perform a reduction reaction to synthesize a diamine compound (b-1).

In formula (2-20), the definitions of R ¹ , R ² , Z ¹ , Z ² , Z ³ , Z ⁴ , a, b, c, d, e, f and g are the same as in formula (2-1) The definitions of R ¹ , R ² , Z ¹ , Z ² , Z ³ , Z ⁴ , a, b, c, d, e, f and g are the same, and will not be repeated here.

The compound represented by formula (2-20) can be synthesized by methods such as Grignard reaction or Friedal-Crafts acylation reaction (Friedal-Crafts acylation reaction), which are generally used to synthesize liquid crystal compounds. .

The diamine compound (b-1) represented by formula (2) is preferably selected from formula (2-2), formula (2-7), formula (2-10), formula (2-15), formula ( 2-17), at least one of the group consisting of diamine compounds represented by formula (2-18).

Based on the usage amount of diamine component (b) being 100 moles, the usage amount of diamine compound (b-1) can be 3 moles to 20 moles, preferably 4 moles to 18 moles, and more preferably 5 moles to 15 moles. When the liquid crystal alignment agent does not use the diamine compound (b-1), the liquid crystal alignment film has the problem of poor UV reliability.

Diamine compound (b-2)

Diamine compounds (b-2) include aliphatic diamine compounds, alicyclic diamine compounds, aromatic diamine compounds, diamine compounds with structural formula (II-1) to formula (II-30), or combinations thereof .

Specific examples of aliphatic diamine compounds include, but are not limited to, 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 Alkanes, or combinations of the above compounds.

Specific examples of alicyclic diamine compounds include, but are not limited to, 4,4'-diaminodicyclohexylmethane, 4,4'-diamino-3,3'-dimethyldicyclohexylamine, 1, 3-Diaminocyclohexane, 1,4-diaminocyclohexane, isophoronediamine, tetrahydrodicyclopentadienediamine, tricyclo[6.2.1.0 ^2,7 ]-undeca Carbenedimethyldiamine, 4,4'-methylenebis(cyclohexylamine), or a combination of the above compounds.

Specific examples of aromatic diamine compounds include, but are not limited to, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylethane, 4,4'-diaminodiphenyl Sulfone, 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-methyleneindenylidene dimethylenediamine, 3,3'-diaminobenzophenone, 3,4'-diaminodi Benzophenone, 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-aminophenoxy)phenyl] Sulfone, 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 [9,10-bis(4-aminophenyl)anthracene], 2,7 -Diamino fluorene, 9,9-bis(4-aminophenyl) fluorene, 4,4'-methylene-bis(2-chloroaniline), 4,4'-(p-phenylene iso Propylene)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-pentyl Cyclohexyl)cyclohexyl]phenyl-methylene-1,3-diaminobenzene {5-[4-(4-n-pentylcyclohexyl)cyclohexyl]phenylmethylene-1,3-diaminobenzene}, 1,1-bis [4-(4-aminophenoxy)phenyl]-4-(4-ethylphenyl)cyclohexane{1,1-bis[4-(4-aminophenoxy)phenyl]-4-(4 -ethylphenyl)cyclohexane}, or a combination of the above compounds.

Diamine compounds having structural formula (II-1) to formula (II-30) are shown below.

In formula (II-1), B ¹ represents -O-, B ² represents a group having a steroid (steroid) skeleton, a trifluoromethyl group, a fluoro group, an alkyl group with a carbon number of 2 to 30, or a group derived from pyridine, pyrimidine, triazine, piperidine or piperazine, etc. A monovalent group with a ring structure of a nitrogen atom.

Specific examples of compounds represented by formula (II-1) include, but are not limited to, 2,4-diaminophenyl ethyl formate (2,4-diaminophenyl ethyl formate), 3,5-diaminophenyl formic acid ethyl Esters (3,5-diaminophenyl ethylformate), 2,4-diaminophenyl propyl formate (2,4-diaminophenyl propyl formate), 3,5-diaminophenyl propyl formate (3,5-diaminophenyl propyl formate), 1-dodecyloxy-2,4-diaminobenzene (1-dodecoxy-2,4-diaminobenzene), 1-hexadecyloxy-2,4-diaminobenzene (1 -hexadecoxy-2,4-diaminobenzene), 1-octadecyloxy-2,4-diaminobenzene (1-octadecoxy-2,4-diaminobenzene), from formula (II-1-1) to formula ( At least one of the compounds represented by II-1-6), or a combination of the above compounds.

Compounds represented by formula (II-1-1) to formula (II-1-6) are shown below.

In formula (II-2), ^B1 is the same as ^B1 in formula (II-1), and ^B3 and ^B4 each independently represent a divalent alicyclic ring, a divalent aromatic ring or a divalent heterocyclic group; ^B5 represents an alkyl group with a carbon number of 3 to 18, an alkoxy group with a carbon number of 3 to 18, a fluoroalkyl group with a carbon number of 1 to 5, a fluoroalkoxy group with a carbon number of 1 to 5, a cyano group or halogen atom.

Specific examples of the compound represented by formula (II-2) include at least one of the compounds represented by formula (II-2-1) to formula (II-2-13). Specifically, compounds represented by formula (II-2-1) to formula (II-2-13) are shown below.

In formula (II-2-10) to formula (II-2-13), s represents an integer of 3 to 12.

In formula (II-3), ^B6 each independently represents a hydrogen atom, an acyl group with 1 to 5 carbons, an alkyl group with 1 to 5 carbons, an alkoxy group with 1 to 5 carbons, or a halogen atom, and B ⁶ in each repeating unit may be the same or different; u represents an integer of 1 to 3.

Specific examples of compounds represented by formula (II-3) include when u is 1: p-diaminobenzene, m-diaminobenzene, o-diaminotoluene, or 2,5-diaminotoluene, etc.; when u When it is 2: 4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-di Aminobiphenyl, 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, etc.; or when u is 3: 1 , 4-bis(4'-aminophenyl)benzene and so on.

Specific examples of the compound represented by formula (II-3) preferably include p-diaminobenzene, 2,5-diaminotoluene, 4,4'-diaminobiphenyl, 3,3'-dimethyl Oxy-4,4'-diaminobiphenyl, 1,4-bis(4'-aminophenyl)benzene or a combination of the above compounds.

In formula (II-4), v represents an integer of 2 to 12.

In formula (II-5), w represents an integer of 1 to 5. The compound represented by formula (II-5) is preferably 4,4'-diamino-diphenylsulfide.

In formula (II-6), B ⁷ and B ⁹ each independently represent a divalent organic group, and B ⁷ and B ⁹ can be the same or different; B ⁸ represents a group derived from pyridine, pyrimidine, triazine, piperidine or piperidine A divalent group with a ring structure containing a nitrogen atom such as oxazine.

In formula (II-7), B ¹⁰ , B ¹¹ , B ¹² and B ¹³ each independently represent a hydrocarbon group with a carbon number of 1 to 12, and B ¹⁰ , B ¹¹ , B ¹² and B ¹³ may be the same or different; X1 Each independently represents an integer of 1 to 3; X2 represents an integer of 1 to 20.

In formula (II-8), B ¹⁴ represents an oxygen atom or a cyclohexylene group; B ¹⁵ represents a methylene group (methylene, -CH ₂ -); B ¹⁶ represents a phenylene group or a cyclohexylene group; B ¹⁷ represents a hydrogen atom or a heptyl group.

Specific examples of the compound represented by formula (II-8) include a compound represented by formula (II-8-1), a compound represented by formula (II-8-2), or a combination of the above compounds.

Compounds represented by formula (II-9) to formula (II-30) are shown below.

In formula (II-17) to formula (II-25), B ¹⁸ preferably represents an alkyl group with a carbon number of 1 to 10 or an alkoxy group with a carbon number of 1 to 10; B ¹⁹ preferably represents a hydrogen atom , an alkyl group having 1 to 10 carbons or an alkoxy group having 1 to 10 carbons.

The diamine compound (b-2) can be used individually or in combination of several types.

Specific examples of diamine compounds (b-2) preferably include, but are not limited to, 1,2-diaminoethane, 4,4'-diaminodicyclohexylmethane, 4,4'-diaminodicyclohexylmethane, 4,4'-diaminobis Phenylmethane, 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, ethyl 2,4-diaminophenylcarboxylate, 1- Octadecyloxy-2,4-diaminobenzene, a compound represented by formula (II-1-1), a compound represented by formula (II-1-2), a compound represented by formula (II-1-4) Compounds represented by formula (II-1-5), compounds represented by formula (II-2-1), compounds represented by formula (II-2-11), p-diaminobenzene, meta - Diaminobenzene, o-diaminobenzene, a compound represented by formula (II-8-1), a compound represented by formula (II-26) to formula (II-30), or a combination of the above compounds.

Based on the usage amount of diamine component (b) being 100 moles, the usage amount of diamine compound (b-2) can be 80 moles to 97 moles, preferably 82 moles to 96 moles, and more preferably 85 moles to 95 moles.

When the polymer (A) in the liquid crystal alignment agent contains the diamine compound (b-2) represented by formula (II-1), formula (II-2), formula (II-26) to formula (II-30) When at least one kind is used, the ultraviolet reliability of the liquid crystal display component can be further improved.

Process for preparing polymer (A)

The polymer (A) may include at least one of polyamic acid and polyimide. In addition, the polymer (A) may further include a polyimide-based block copolymer. The preparation methods of the above-mentioned various polymers are further described below.

Method for preparing polyamic acid

The method for preparing polyamic acid is to first dissolve the mixture in a solvent, wherein the mixture includes tetracarboxylic dianhydride component (a) and diamine component (b), and carry out polycondensation at a temperature of 0°C to 100°C reaction. After reacting for 1 hour to 24 hours, the reaction solution is distilled under reduced pressure with an evaporator to obtain polyamic acid. Alternatively, the reaction solution is poured into a large amount of poor solvent to obtain a precipitate. Then, the precipitate is dried under reduced pressure to obtain polyamic acid.

The solvent used in the polycondensation reaction may be the same as or different from the solvent in the liquid crystal alignment agent described below, and the solvent used in the polycondensation reaction is not particularly limited as long as it can dissolve the reactants and products. The solvents preferably include but are not limited to (1) aprotic polar solvents, such as: N-methyl-2-pyrrolidinone (N-methyl-2-pyrrolidinone, NMP for short), N,N-dimethylacetamide , N,N-dimethylformamide, dimethyl sulfoxide, γ-butyrolactone, tetramethylurea or hexamethylphosphoric triamine and other aprotic polar solvents; or (2) phenolic solvents , For example: phenolic solvents such as m-cresol, xylenol, phenol or halogenated phenols. Based on 100 parts by weight of the total mixture, the solvent used in the polycondensation reaction is preferably used in an amount of 200 to 2000 parts by weight, and more preferably 300 to 1800 parts by weight.

It should be noted that in the polycondensation reaction, the solvent can be combined with an appropriate amount of poor solvent, and the poor solvent will not cause the precipitation of polyamic acid. Poor solvents can be used alone or in combination, and they include but are not limited to (1) alcohols, such as: methanol, ethanol, isopropanol, cyclohexanol, ethylene glycol, propylene glycol, 1,4- Alcohols such as butylene glycol or triethylene glycol; (2) ketones, such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.; (3) esters, For example: esters of methyl acetate, ethyl acetate, butyl acetate, diethyl oxalate, diethyl malonate or ethylene glycol ethyl ether acetate; (4) ethers, such as: diethyl ether, 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, or diethylene glycol Ethers such as dimethyl ether; (5) halogenated hydrocarbons, such as dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene or o- Halogenated hydrocarbons such as dichlorobenzene; or (6) hydrocarbons, such as tetrahydrofuran, hexane, heptane, octane, benzene, toluene or xylene or any combination of the above solvents. Based on 100 parts by weight of the diamine component (b), the amount of the poor solvent is preferably 0 to 60 parts by weight, and more preferably 0 to 50 parts by weight.

Method for preparing polyimide

The method for preparing polyimide is obtained by heating the polyamic acid prepared by the above method for preparing polyamic acid in the presence of a dehydrating agent and a catalyst. During the heating process, the amic acid functional group in the polyamic acid can be converted into an imide functional group through a dehydration dead cycle reaction (ie, imidization).

The solvent used in the dehydration dead cycle reaction can be the same as the solvent (B) in the liquid crystal alignment agent, so it will not be repeated here. Based on the amount of polyamic acid used as 100 parts by weight, the amount of solvent used in the dehydration dead cycle reaction is preferably 200 to 2000 parts by weight, and more preferably 300 to 1800 parts by weight.

In order to obtain a better degree of imidization of the polyamic acid, the operating temperature of the dead cycle dehydration reaction is preferably from 40°C to 200°C, more preferably from 40°C to 150°C. If the operating temperature of the dehydration dead cycle reaction is lower than 40° C., the imidization reaction will not be complete, and the degree of imidization of the polyamic acid will be reduced. However, if the operating temperature of the dehydration dead cycle reaction is higher than 200° C., the weight average molecular weight of the obtained polyimide is low.

The dehydrating agent used in the dehydration dead cycle reaction can be selected from acid anhydride compounds, for example, acid anhydride compounds such as acetic anhydride, propionic anhydride or trifluoroacetic anhydride. Based on 1 mole of the polyamic acid, the amount of the dehydrating agent is 0.01 mole to 20 mole. The catalyst used in the dehydration dead cycle reaction can be selected from (1) pyridine compounds, such as: pyridine compounds such as pyridine, collidine or lutidine; (2) tertiary amine compounds, such as: Tertiary amine compounds such as triethylamine. Based on 1 mole of the dehydrating agent, the catalyst can be used in an amount of 0.5 moles to 10 moles.

The imidization rate of the polymer (A) may be 30% to 90%, preferably 35% to 85%, and more preferably 40% to 80%. When the imidization rate of the polymer (A) in the liquid crystal alignment agent is within the above range, the UV reliability of the formed liquid crystal alignment film can be further improved.

Method for preparing polyimide-based block copolymers

Polyimide block copolymer is selected from polyamic acid block copolymer, polyimide block copolymer, polyamic acid-polyimide block copolymer or the above-mentioned polymer random combination.

The method for preparing polyimide-based block copolymers is preferably to first dissolve the starting material in a solvent, and carry out polycondensation reaction, wherein the starting material includes at least one polyamic acid and/or at least one polyamic acid imide, and may further include a carboxylic anhydride component and a diamine component.

The carboxylic anhydride component and the diamine component in the starter can be the same as the tetracarboxylic dianhydride component (a) and the diamine component (b) used in the method for preparing polyamic acid, and used for polyamic acid The solvent in the condensation reaction may be the same as the solvent in the liquid crystal alignment agent described below, which will not be repeated here.

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

The starting material preferably includes but is not limited to (1) two kinds of polyamic acids with different end groups and different structures; (2) two kinds of polyimides with different end groups and different structures; (3) Polyamic acid and polyimide with different terminal groups and different structures; (4) polyamic acid, carboxylic anhydride component and diamine component, wherein at least one of the carboxylic anhydride component and the diamine component One is different from the structure of the carboxylic anhydride component and the diamine component used to form polyamic acid; (5) polyimide, carboxylic anhydride component and diamine component, wherein, the carboxylic anhydride component and the diamine component At least one of the amine components is different from the structure of the carboxylic anhydride component and the diamine component used to form the polyimide; (6) polyamic acid, polyimide, carboxylic anhydride component and diamine Components, wherein at least one of the carboxylic anhydride component and the diamine component is different from the structure of the carboxylic anhydride component and the diamine component used to form polyamic acid or polyimide; (7) two (8) Two kinds of polyimides, carboxylic anhydride components and diamine components with different structures; (9) Two kinds of terminal groups Anhydride-based polyamic acid and diamine components with different structures; (10) two kinds of polyamic acid and carboxylic anhydride components with amine-based terminal groups and different structures; (11) two kinds of terminal groups with acid anhydride or (12) two kinds of polyimide and carboxylic acid anhydride components whose terminal groups are amine groups and have different structures.

The polyamic acid, polyimide, and polyimide-based block copolymers are preferably end-modified polymers that have been first adjusted in molecular weight within the range that does not affect the efficacy of the present invention. By using terminal-modified polymers, the coating performance of the liquid crystal alignment agent can be improved. The method of preparing the end-modified polymer can be obtained by adding a monofunctional compound while the polyamic acid undergoes polycondensation reaction.

Specific examples of monofunctional compounds include but are not limited to (1) monobasic acid anhydrides, such as: maleic anhydride, phthalic anhydride, itaconic anhydride, n-decyl succinic anhydride, n-dodecyl succinic anhydride, n-tetradecyl anhydride, Monobasic acid anhydrides such as alkyl succinic anhydride or n-hexadecyl succinic 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, Monoamine compounds such as n-octadecylamine or n-eicosylamine; or (3) monoisocyanate compounds, such as monoisocyanate compounds such as phenyl isocyanate or naphthyl isocyanate.

solvent (B)

The solvent used in the liquid crystal alignment agent of the present invention is not particularly limited, as long as it can dissolve the polymer (A) and any other components and does not react with it. The solvent used may also use together the poor solvent used at the time of synthesizing this polyamic acid at the same time.

Specific examples of the solvent (B) include, but are not limited to, N-methyl-2-pyrrolidone, γ-butyrolactone, γ-butyrolactam, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol mono Methyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol n-propyl ether, ethyl Glycol isopropyl ether, ethylene glycol n-butyl ether, ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol dimethyl ether, Ethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate or N,N-dimethylformamide or N,N-dimethylacetamide (N,N-dimethylacetamide), etc. The solvent (B) can be used individually or in combination of multiple types.

Based on 100 parts by weight of the polymer (A), the used amount of the solvent (B) is 800 to 4000 parts by weight, preferably 900 to 3500 parts by weight, and more preferably 1000 to 3000 parts by weight.

Additive (C)

In the range that does not affect the effectiveness of the present invention, the liquid crystal alignment agent can optionally add additives (C), wherein the additives (C) include compounds with at least two epoxy groups, silane compounds with functional groups, or a combination thereof.

Compounds having at least two epoxy groups include, but are not limited to, 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-Di Bromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraepoxypropyl-2,4-hexanediol, N,N,N',N'-tetraepoxypropyl- m-Xylylenediamine, 1,3-bis(N,N-diepoxypropylaminomethyl)cyclohexane, N,N,N',N'-tetraepoxypropyl-4,4 '-diaminodiphenylmethane, 3-(N,N-diepoxypropyl)aminopropyltrimethoxysilane, or a combination of the above compounds.

The compound which has at least two epoxy groups can be used individually or in combination of several types.

Based on 100 parts by weight of the polymer (A), the compound having at least two epoxy groups may be used in an amount of 0 to 40 parts by weight, and preferably 0.1 to 30 parts by weight.

Specific examples of silane compounds having functional groups include, but are not limited to, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltrimethoxysilane, -Aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyl Methyldimethoxysilane, 3-ureidopropyltrimethoxysilane (3-ureidopropyltrimethoxy silane), 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyl Trimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltri Ethylenetriamine, 10-trimethoxysilyl-1,4,7-triazidecane, 10-triethoxysilyl-1,4,7-triazidecane, 9-trimethoxysilane -3,6-diazinonyl acetate, 9-triethoxysilyl-3,6-diazinonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N -Benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N - bis(oxyethylene)-3-aminopropyltrimethoxysilane, N-bis(oxyethylene)-3-aminopropyltriethoxysilane, or a combination of the aforementioned compounds.

The silane compound which has a functional group can be used individually or in combination of several types.

Based on 100 parts by weight of the polymer (A), the amount of the silane compound having a functional group may be 0 to 10 parts by weight, and preferably 0.5 to 10 parts by weight.

The additive (C) is preferably used in an amount of 0.5 to 50 parts by weight, and more preferably 1 to 45 parts by weight, based on 100 parts by weight of the total polymer (A).

<Preparation method of liquid crystal alignment agent>

The preparation method of the liquid crystal alignment agent is not particularly limited, and a general mixing method can be used for preparation. For example, the polymer (A) is first added to the solvent (B) at a temperature of 0° C. to 200° C., and the additive (C) is optionally added. Next, use a stirring device to continue stirring until it dissolves. Furthermore, additionally, it is preferable to add the solvent (B) at a temperature of 20°C to 60°C.

<Manufacturing Method of Liquid Crystal Alignment Film>

The liquid crystal alignment film of the present invention can be formed from the above-mentioned liquid crystal alignment agent.

Specifically, the preparation method of the liquid crystal alignment film may be, for example: coating the liquid crystal alignment agent on the surface of the substrate by roll coating method, spin coating method, printing method or ink-jet method. , forming a precoat. Next, pre-bake treatment, post-bake treatment, and alignment treatment are performed on the pre-coat layer to obtain a substrate on which a liquid crystal alignment film is formed.

The purpose of the pre-baking treatment is to volatilize the organic solvent in the pre-coating. The operating temperature of the pre-baking treatment is preferably from 30°C to 120°C, more preferably from 40°C to 110°C, and especially preferably from 50°C to 100°C.

There is no special limitation on the alignment treatment, and the cloth made of fibers such as nylon, rayon or cotton can be wound on the drum and rubbed in a certain direction for alignment.

The purpose of the post-baking treatment step is to make the polymer in the pre-coating layer further undergo a dead cycle dehydration (imidization) reaction. The operating temperature of the post-baking treatment is preferably from 150°C to 300°C, more preferably from 180°C to 280°C, and especially preferably from 200°C to 250°C.

<Liquid crystal display module and manufacturing method thereof>

The liquid crystal display component of the present invention includes a liquid crystal alignment film formed by the liquid crystal alignment agent of the present invention. The liquid crystal display module of the present invention can be manufactured as follows.

Prepare two substrates on which the liquid crystal alignment film is formed as described above, arrange liquid crystal between the two substrates, and manufacture a liquid crystal cell. In order to manufacture a liquid crystal cell (cell), the following two methods are mentioned, for example.

The first method: first, two substrates are arranged oppositely across a gap (intercellular gap), so that their respective liquid crystal alignment films face each other; the peripheral parts of the two substrates are bonded together using a sealant; Liquid crystal is injected into the intercellular space divided by the sealant; and the injection hole is closed, so that the liquid crystal cell can be manufactured.

The second method: a method called the One Drop Fill (ODF for short) method. First of all, on a predetermined position on one of the two substrates forming the liquid crystal alignment film, for example, an ultraviolet curable sealing material is coated; liquid crystal is dropped on the surface of the liquid crystal alignment film; then, the other substrate is bonded to make the liquid crystal alignment film facing each other; next, the entire surface of the substrate is irradiated with ultraviolet light to cure the sealant, whereby a liquid crystal cell can be manufactured.

In the case of using any of the above methods, it is desirable to heat the liquid crystal cell to the temperature at which the liquid crystal used is in the isotropic phase, and then slowly cool it to room temperature, thereby removing the flow alignment when filling the liquid crystal.

Then, the liquid crystal display module of the present invention can be obtained by attaching a polarizer to the outer surface of the liquid crystal cell.

As the sealing agent, for example, an epoxy resin containing a curing agent and alumina balls as spacers can be used.

The polarizing plate used on the outside of the liquid crystal cell includes a polarizing film called a "H film" obtained by sandwiching polyvinyl alcohol (polyvinyl alcohol) stretch alignment with cellulose acetate protective films and absorbing iodine. ) to form a polarizer or a polarizer formed by the H film itself.

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

FIG. 1 is a side view of a liquid crystal display module according to an embodiment of the present invention. The liquid crystal display assembly 100 includes a first unit 110 , a second unit 120 and a liquid crystal unit 130 , wherein the second unit 120 is disposed separately 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, and the first liquid crystal alignment film 116 is located on one side of the liquid crystal cell 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, and the second liquid crystal alignment film 126 is located on the other side of the liquid crystal cell 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, etc., wherein the transparent materials include but not limited to alkali-free glass, soda-lime glass, hard glass (Pyles glass), quartz, etc. used in liquid crystal display devices. Glass, polyethylene terephthalate, polybutylene, terephthalate, polyethersulfone or polycarbonate, etc. The materials of the first conductive film 114 and the second conductive film 124 are selected from tin oxide (SnO ₂ ), indium oxide-tin oxide (In ₂ O ₃ —SnO ₂ ), and the like.

The first liquid crystal alignment film 116 and the second liquid crystal alignment film 126 are each the above-mentioned liquid crystal alignment film, 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 may be generated between the first conductive film 114 and the second conductive film 124 . The electric field can drive the liquid crystal unit 130 , thereby changing the arrangement of the liquid crystal molecules in the liquid crystal unit 130 . The liquid crystals used in the liquid crystal unit 130 can be used alone or in combination, and the liquid crystals include but are not limited to diaminobenzene liquid crystals, pyridazine (pyridazine) liquid crystals, Schiff Base (shiff Base) liquid crystals, azoxy ( azoxy) liquid crystals, biphenyl liquid crystals, phenylcyclohexane liquid crystals, ester liquid crystals, terphenyl, biphenylcyclohexane liquid crystals, pyrimidine ( pyrimidine-based liquid crystals, dioxane-based liquid crystals, bicyclooctane-based liquid crystals, or cubane-based liquid crystals, etc. Cholesteryl liquid crystals such as cholesteryl nonanoate and cholesterylcarbonate, or chiral agents with trade names "C-15" and "CB-15" (manufactured by Merck & Co., Ltd.), Or a ferroelectric liquid crystal such as p-decyloxybenzylidene-p-amino-2-methylbutyl cinnamate.

Synthesis example of polymer (A)

Synthesis Example A-1-1 to Synthesis Example A-1-3 of the polymer (A) are described below.

Synthesis Example A-1-1

A nitrogen inlet, a stirrer, a condenser, and a thermometer were arranged on a four-necked conical flask with a volume of 500 milliliters, and nitrogen was introduced. Then, in the four-necked conical flask, add 1.51 grams (0.0025 moles) of the diamine compound represented by formula (2-10) (abbreviated as b-1-1), 9.42 grams (0.0475 moles) of 4,4'- Diaminodiphenylmethane (4,4'-diaminodiphenylmethane) is referred to as (b-2-1), and 80 grams of N-methyl-2-pyrrolidone (N-methyl-2-pyrrolidone, referred to as NMP), and stirred at room temperature until dissolved. Then, add 1.25 grams (0.005 moles) of tetracarboxylic dianhydride compounds represented by formula (1-1) (abbreviated as a-1-1), 8.82 grams (0.045 moles) of 1,2,3,4- Cyclobutane tetracarboxylic dianhydride (1,2,3,4-cyclobutane tetracarboxylic dianhydride) (abbreviated as a-2-1) and 20 grams of NMP were reacted at room temperature for 2 hours. After the reaction was finished, the reaction solution was poured into 1500 milliliters of water, so that the polymer was precipitated. Then, the obtained polymer was filtered, washed with methanol and filtered three times, placed in a vacuum oven, and dried at a temperature of 60° C. to obtain the polymer (A-1-1).

Synthesis Example A-1-2 to Synthesis Example A-1-3

Synthesis Example A-1-2 to Synthesis Example A-1-3 are the same steps as Synthesis Example A-1-1 to prepare polymer (A-1-2) to polymer (A-1-3) respectively , and its difference lies in: changing the type and usage amount of the monomer (as shown in Table 1).

Synthesis Example of Polymer

Synthesis Example A-2-1 to Synthesis Example A-2-10 of the polymer are described below.

Synthesis Example A-2-1

A nitrogen inlet, a stirrer, a condenser, and a thermometer were arranged on a four-necked conical flask with a volume of 500 milliliters, and nitrogen was introduced. Then, in the four-necked conical flask, add 1.51 grams (0.0025 moles) of the diamine compound represented by formula (2-10) (abbreviated as b-1-1), 9.42 grams (0.0475 moles) of 4,4'- Diaminodiphenylmethane (4,4'-diaminodiphenylmethane) is referred to as (b-2-1), and 80 grams of N-methyl-2-pyrrolidone (N-methyl-2-pyrrolidone, referred to as NMP), and stirred at room temperature until dissolved. Then, add 1.25 grams (0.005 moles) of tetracarboxylic dianhydride compounds represented by formula (1-1) (abbreviated as a-1-1), 8.82 grams (0.045 moles) of 1,2,3,4- Cyclobutane tetracarboxylic dianhydride (1,2,3,4-cyclobutane tetracarboxylic dianhydride) (referred to as a-2-1) and 20 grams of NMP. After reacting at room temperature for 6 hours, 97 g of NMP, 2.55 g of acetic anhydride, and 19.75 g of pyridine were added, the temperature was raised to 60° C., and stirring was continued for 2 hours to carry out imidization reaction. After the reaction was finished, the reaction solution was poured into 1500 milliliters of water, so that the polymer was precipitated. Then, the obtained polymer was filtered, washed with methanol and filtered three times, placed in a vacuum oven, and dried at a temperature of 60° C. to obtain the polymer (A-2-1).

Synthesis Example A-2-2 to Synthesis Example A-2-10

Synthesis Example A-2-2 to Synthesis Example A-2-10 are the same steps as Synthesis Example A-2-1 to prepare polymer (A-2-2) to polymer (A-2-10) respectively , and its difference lies in: changing the type and usage amount of the monomer (as shown in Table 1).

Comparative Synthesis Example A-3-1 to Comparative Synthesis Example A-3-3 of Polymers

Comparing Synthesis Example A-3-1 to Comparison Synthesis Example A-3-3 is to prepare respectively polymer (A-3-1) to polymer (A-3- 3), and its difference is: change the kind of monomer and its usage amount (as shown in Table 2).

Comparative Synthesis Example A-3-4 to Comparative Synthesis Example A-3-6 of Polymers

Comparative synthesis example A-3-4 to comparison synthesis example A-3-6 is to prepare polymer (A-3-4) to polymer (A-3- 6), and its difference lies in: change the type and usage amount of monomer, catalyst and dehydrating agent (as shown in Table 2).

The compounds corresponding to the abbreviations in Table 1 and Table 2 are as follows.

Abbreviation Ingredients

Bicyclo[3.3.0]octane-2,4,6,8-tetracarboxylic dianhydride

Bicyclo[4.3.0]nonane-2,4,7,9-tetracarboxylic dianhydride

Tricyclo[6.3.0.0 ^2,6 ]undecane-35911-tetracarboxylic dianhydride

a-2-1

1,2,3,4-cyclobutane tetracarboxylic dianhydride (1,2,3,4-cyclobutane tetracarboxylic dianhydride)

a-2-2Pyromellitic dianhydride

b-2-1 4,4'-Diaminodiphenylmethane (4,4'-diaminodiphenylmethane)

b-2-2 4,4'-diaminodiphenyl ether (4,4'-diaminodiphenyl ether)

b-2-3 p-diaminobenzene (p-diaminobenzene)

b-2-4 1-octadecoxy-2,4-diaminobenzene (1-octadecoxy-2,4-diaminobenzene)

Table 2

Examples and Comparative Examples of Liquid Crystal Alignment Agents, Liquid Crystal Alignment Films, and Liquid Crystal Display Modules

Examples 1 to 13 and Comparative Examples 1 to 6 of liquid crystal alignment agents, liquid crystal alignment films, and liquid crystal display components are described below:

a. Liquid crystal alignment agent

Weigh the polymer (A-1-1) of 100 weight parts, the N-methyl-2-pyrrolidone (abbreviated as B-1) of 1200 weight parts and the ethylene glycol n-butyl ether (abbreviated as B-1) of 600 weight parts -2), and stirring and mixing at room temperature to form the liquid crystal alignment agent of Example 1.

b. Liquid crystal alignment film and liquid crystal display components

The above-mentioned liquid crystal alignment agent was coated on two glass substrates with a conductive film made of ITO (indium-tin-oxide) with a printing machine (manufactured by Nippon Photo Printing Co., Ltd., model number S15-036) to form a preliminary coating. Afterwards, the glass substrate was placed on a heating plate, and prebaked at a temperature of 100° C. for 5 minutes. Next, post-baking was performed in a circulating oven at a temperature of 220° C. for 30 minutes. Finally, after the alignment treatment, the glass substrate on which the liquid crystal alignment film of Embodiment 1 is formed can be obtained.

Of the two glass substrates obtained above on which the liquid crystal alignment film was formed, one of them was coated with hot pressing adhesive, and the other was sprinkled with a 4 μm spacer. Next, the two glass substrates were bonded together, and a pressure of 10 kg was applied by a hot press, and thermal compression bonding was carried out at a temperature of 150° C. Then, liquid crystal injection was performed with a liquid crystal injection machine (manufactured by Shimadzu Corporation, model number ALIS-100X-CH). Next, seal the liquid crystal injection port with UV-curable glue, light the UV-curable glue with UV light, and perform liquid crystal annealing treatment (annealing treatment) in an oven at a temperature of 60°C and a time of 30 minutes. , the liquid crystal display module of Example 1 can be obtained.

The liquid crystal display module of Example 1 was evaluated by various evaluation methods described below, and the results are shown in Table 3.

Example 2 to Example 13

The liquid crystal alignment agents, liquid crystal alignment films, and liquid crystal display components of Examples 2 to 13 were prepared in the same steps as in Example 1, and the difference is that the types and amounts of ingredients were changed, as shown in Table 3. Show. The liquid crystal display components prepared in Examples 2 to 13 were evaluated in the following evaluation manner, and the results are shown in Table 3.

Comparative Example 1 to Comparative Example 6

The liquid crystal alignment agents, liquid crystal alignment films, and liquid crystal display components of Comparative Example 1 to Comparative Example 6 were prepared in the same steps as in Example 1, except that the types and amounts of ingredients were changed, as shown in Table 4 . The liquid crystal display modules prepared in Comparative Example 1 to Comparative Example 6 were evaluated in the following evaluation manner, and the results are shown in Table 4.

The compounds corresponding to the abbreviations in Table 3 and Table 4 are as follows.

Evaluation method

a. Imidization rate

The imidization rate refers to the ratio of the number of imide rings calculated based on the total amount of the number of amic acid functional groups and the number of imide rings in the polymer, expressed as a percentage.

The detection method is to dry the polymers of the synthesis examples under reduced pressure, and dissolve them in a suitable deuteration solvent, such as deuterated dimethyl sulfoxide, using tetramethylsilane as a reference substance, from The imidization ratio (%) can be calculated from the result of measuring ¹ H-NMR ( ¹ H-Nuclear magnetic resonance, ¹ H-NMR) at room temperature (for example, 25° C.) from mathematical formula (1).

Δ1: The peak area generated by the chemical shift of NH protons near 10ppm;

Δ2: peak area of other protons;

α: the number ratio of one proton of NH group to other protons in the precursor of the polymer (polyamic acid).

b. UV reliability

The UV reliability of liquid crystal alignment film is evaluated by the voltage retention rate of liquid crystal display components. Further, the measurement method of the voltage holding ratio of the liquid crystal display component is as follows.

The voltage holding ratios of the liquid crystal display components of Example 1 to Example 13 and Comparative Example 1 to Comparative Example 6 were respectively measured using an electrical measuring machine (manufactured by Toyo Corporation, Model 6254). The test condition is to apply a voltage of 4 volts, release the voltage after 2 milliseconds, and measure the voltage retention rate (referred to as VHR1) after 1667 milliseconds from the release. Next, after irradiating the liquid crystal display assembly with 4200mJ/cm ² of ultraviolet light (the model of the ultraviolet light irradiation machine is KN-SH48K1; manufactured by Guangneng Xingye), measure the voltage retention rate (meter) after the ultraviolet light irradiation under the same test conditions for VHR2). Finally, the percentage change of the voltage retention rate (calculated as VHR ^UV (%)) can be obtained by calculating with the mathematical formula (2). A lower percentage change in voltage retention indicates better UV reliability.

The evaluation criteria for the percentage change in the voltage retention rate are as follows.

◎: VHR ^UV <5%

○: 5%≤VHR ^UV <10%

△: 10%≤VHR ^UV <20%

╳: 20%≤VHR ^UV

table 3

Table 3 (continued)

Table 4

<Evaluation result>

It can be known from Table 3 and Table 4 that the liquid crystal alignment film formed by simultaneously using tetracarboxylic dianhydride compound (a-1) and diamine compound (b-1) in polymer (A) (Example 1 to Example 13) compared to the UV reliability of the liquid crystal alignment film (Comparative Examples 1, 3, 4 and 6) formed by using the polymer (A) that does not contain the tetracarboxylic dianhydride compound (a-1); Moreover, the UV reliability of the liquid crystal alignment films (Comparative Examples 2, 3, 5 and 6) formed by using the polymer (A) not containing the diamine compound (b-1) is not good.

In addition, when the imidization rate of the polymer (A) in the liquid crystal alignment agent is 30% to 90%, the UV reliability of the formed liquid crystal alignment film (Examples 7-12) is better.

Also, when the polymer (A) in the liquid crystal alignment agent contains diamine compounds (b-2) represented by formula (II-1), formula (II-2), formula (II-26) to formula (II-30) ), the UV reliability of the formed liquid crystal alignment films (Examples 3, 6, 9 and 12) is particularly good.

In summary, the polymer in the liquid crystal alignment agent of the present invention is formed by a tetracarboxylic dianhydride component containing a tetracarboxylic dianhydride compound of a specific structure and a diamine component containing a diamine compound of a specific structure, Therefore, when the liquid crystal alignment agent is applied to a liquid crystal alignment film, the liquid crystal alignment film has better ultraviolet reliability, and thus is suitable for liquid crystal display components.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the various embodiments of the present invention. scope.

Claims (4)

1. A liquid crystal alignment agent, characterized in that, comprising: polymer (A); and solvent (B), Wherein, the polymer (A) is obtained by the reaction of a mixture, and the mixture includes a tetracarboxylic dianhydride component (a) and a diamine component (b), The tetracarboxylic dianhydride component (a) includes a tetracarboxylic dianhydride compound (a-1) represented by formula (1), In formula (1), P ¹ , P ² , P ³ and P ⁴ each independently represent a single bond or a methylene group; j represents an integer from 1 to 3, wherein, based on the tetracarboxylic dianhydride component (a) The total number of moles is 100, and the usage amount of the tetracarboxylic dianhydride compound (a-1) is 5 moles to 50 moles; and The diamine component (b) includes a diamine compound (b-1) represented by formula (2), In formula (2), Y ¹ represents an alkylene group having a carbon number of 1 to 12; Y ² represents a group having a steroid skeleton or a group represented by formula (2-1), In formula (2-1), R ¹ each independently represents a fluorine atom or a methyl group; R ² represents a hydrogen atom, a fluorine atom, an alkyl group with 1 to 12 carbons, a fluoroalkyl group with 1 to 12 carbons, a carbon Alkoxy, -OCH ₂ F, -OCHF ₂ or -OCF ₃ with a number of 1 to 12; Z ¹ , Z ² and Z ³ each independently represent a single bond, an alkylene group having 1 to 3 carbon atoms, -O-, Z ⁴ are independently indicated R ^a and R ^b each independently represent a fluorine atom or a methyl group, h and i each independently represent 0, 1 or 2; a represents 0, 1 or 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, and e+f+g≥1, wherein, based on the The total number of moles of the diamine component (b) is 100 moles, and the usage amount of the diamine compound (b-1) is 3 moles to 20 moles. 2 . The liquid crystal alignment agent according to claim 1 , wherein the imidization rate of the polymer (A) is 30% to 90%. 3 . 3. A liquid crystal alignment film, characterized in that it is formed from the liquid crystal alignment agent according to claim 1 or 2. 4. A liquid crystal display module, characterized in that it comprises the liquid crystal alignment film according to claim 3.