CN110337608B

CN110337608B - Liquid crystal aligning agent, liquid crystal alignment film, liquid crystal element and polyorganosiloxane

Info

Publication number: CN110337608B
Application number: CN201880013894.4A
Authority: CN
Inventors: 村上嘉崇; 片桐宽; 广瀬阳一; 冈田敬
Original assignee: JSR Corp
Current assignee: JSR Corp
Priority date: 2017-03-07
Filing date: 2018-02-20
Publication date: 2023-01-17
Anticipated expiration: 2038-02-20
Also published as: WO2018163802A1; CN110337608A; KR102225388B1; JPWO2018163802A1; TW201839111A; TWI785018B; KR20190102074A; JP7226305B2

Abstract

The present disclosure relates to a liquid crystal aligning agent, a liquid crystal alignment film, a liquid crystal device, and a polyorganosiloxane. The liquid crystal aligning agent contains a silicon-containing compound having a cyclic ether group and a functional group B which reacts with the cyclic ether group. An example of the functional group B of the silicon-containing compound is a functional group that reacts with a cyclic ether group by heat. An example of the silicon-containing compound is a polymer [ P ] having a siloxane skeleton. According to the liquid crystal aligning agent of the present disclosure, a liquid crystal element excellent in reliability against heat can be obtained.

Description

Liquid crystal aligning agent, liquid crystal alignment film, liquid crystal element and polyorganosiloxane

Cross reference to related applications

The present application is based on japanese application No. 2017-43288 filed on 3/7/2017, and the contents of the description are cited in the present application.

Technical Field

The present disclosure relates to a liquid crystal aligning agent, a liquid crystal alignment film, a liquid crystal device, and a polyorganosiloxane.

Background

As the liquid crystal element, various liquid crystal elements are known, such as a liquid crystal element using a Nematic liquid crystal having positive dielectric anisotropy, typified by a Twisted Nematic (TN) type, a Super Twisted Nematic (STN) type, or the like, a Vertical Alignment (VA) type liquid crystal element using a Vertical (homeotropic) Alignment mode of a Nematic liquid crystal having negative dielectric anisotropy, and a lateral electric Field type liquid crystal element Switching a liquid crystal aligned In parallel (homeotropic) by an electric Field parallel to a substrate, typified by an In-Plane Switching (IPS) type, a Fringe Field Switching (FFS) type, or the like.

These liquid crystal elements are provided with a liquid crystal alignment film having a function of aligning liquid crystal molecules in a certain direction. As a material used for producing the liquid crystal alignment film, polyamic acid, polyimide, polyamide, polyester, polyorganosiloxane, and the like are known, and particularly, polyamic acid and polyimide have been used preferably since long since they are excellent in heat resistance, mechanical strength, affinity with liquid crystal molecules, and the like (for example, see patent documents 1 to 3). In the production of a liquid crystal device, the liquid crystal alignment film is formed using a liquid crystal aligning agent in which these polymer components are dissolved in an organic solvent.

Patent document 4 discloses a liquid crystal aligning agent containing a polyorganosiloxane obtained by reacting a mixture of trifunctional and tetrafunctional hydrolyzable silane compounds in the presence of oxalic acid and an alcohol. Patent document 4 describes that a liquid crystal alignment film formed from the liquid crystal aligning agent is excellent in vertical alignment properties and heat resistance.

Liquid crystal elements have been mainly marketed as televisions, mobile and tablet computers, but have been widely used as display devices in recent years. Liquid crystal elements find wide new applications such as in-vehicle devices, digital signage, and industrial applications, and are used in a variety of applications.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. Hei 4-153622

Patent document 2: japanese patent laid-open No. 56-91277A

Patent document 3: japanese patent laid-open publication No. 11-258605

Patent document 4: japanese patent laid-open publication No. Hei 9-281502

Disclosure of Invention

Problems to be solved by the invention

In the new market of liquid crystal devices, durability under severe use environments is sometimes required, and high reliability over the conventional technology is sometimes required. For example, if the heat-resistant material is used at a high temperature in summer or in a hot zone, heat resistance (thermal reliability) is required for a long time. On the other hand, the contribution rate of the liquid crystal alignment film in direct contact with the liquid crystal layer is large for the display quality of the liquid crystal display panel. Therefore, it is required that the liquid crystal alignment film hardly change in voltage holding ratio and driving characteristics and hardly cause a reduction in display quality even when the liquid crystal display panel is exposed to a high temperature condition.

The present disclosure has been made in view of the above circumstances, and an object thereof is to provide a liquid crystal element having excellent reliability against heat.

Means for solving the problems

According to the present disclosure, the following means are provided.

< 1 > a liquid crystal aligning agent comprising a silicon-containing compound having a cyclic ether group and a functional group B reactive with the cyclic ether group.

< 2 > a liquid crystal alignment film formed using the liquid crystal aligning agent according to the < 1 >.

< 3 > a liquid crystal device comprising the liquid crystal alignment film according to the above < 2 >.

< 4 > a polyorganosiloxane having a cyclic ether group and a functional group B which reacts with the cyclic ether group.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the liquid crystal aligning agent of the present disclosure, a liquid crystal element excellent in reliability against heat can be obtained.

Detailed Description

< liquid Crystal aligning agent >

The liquid crystal aligning agent of the present disclosure contains a silicon-containing compound having a cyclic ether group and a functional group that reacts with the cyclic ether group (hereinafter, also referred to as "silicon-containing compound [ a ]"). The silicon-containing compound [ A ] has a silicon-containing structure with high thermal stability and a self-crosslinkable group. Hereinafter, each component contained in the liquid crystal aligning agent of the present disclosure and other components optionally blended will be described.

< silicon-containing Compound [ A ] >)

The cyclic ether group of the silicon-containing compound [ A ] is preferably an oxetanyl group or an oxetanyl group, and more preferably an oxetanyl group, in view of high reactivity due to heat. The functional group that reacts with the cyclic ether group (hereinafter, also referred to as "functional group B") is preferably a functional group that reacts with the cyclic ether group by heat, in view of self-crosslinking by heating at the time of post-baking and further improving the storage stability of the liquid crystal aligning agent. Specific examples of the functional group B include a carboxyl group, an isocyanate group, a hydroxyl group, an amino group, and an alkoxymethyl group, and examples thereof include a carboxyl group, an isocyanate group, and a group in which a hydroxyl group or an amino group is protected with a protecting group. Among them, the functional group B is preferably a carboxyl group or a protected carboxyl group (hereinafter, also referred to as "protected carboxyl group") in terms of better storage stability and higher reactivity with a cyclic ether group by heating.

The protected carboxyl group is preferably one which is released by heat to form a carboxyl group. Specific examples of the protected carboxyl group include: a structure represented by the following formula (1), an acetal ester structure of a carboxylic acid, a ketal ester structure of a carboxylic acid, and the like.

[ solution 1]

(in the formula (1), R ¹¹ 、R ¹² And R ¹³ Each independently is an alkyl group having 1 to 10 carbon atoms or a monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, or R ¹¹ And R ¹² Are bonded to each other and R ¹¹ And R ¹² The bonded carbon atoms together form a C4-20 divalent alicyclic hydrocarbon group or cyclic ether group, and R ¹³ An alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms. "+" indicates a bond)

Examples of the silicon-containing compound [ A ] include low-molecular silane compounds and polyorganosiloxanes. When the silicon-containing compound [ A ] is a low molecular weight silane compound, for example, an alkoxysilane compound having a cyclic ether group and a functional group B can be mentioned. Among them, the silicon-containing compound [ a ] is preferably a polymer having a siloxane skeleton, that is, a polyorganosiloxane having a cyclic ether group and a functional group B (hereinafter, also referred to as "polymer [ P ]"), in terms of obtaining a liquid crystal device having a higher effect of improving thermal reliability, a high solvent resistance of the obtained liquid crystal alignment film, and a better liquid crystal alignment property and voltage holding ratio.

< Polymer [ P ] >, and

the method for synthesizing the polymer [ P ] is not particularly limited, and preferred synthesis methods include the following methods 1 to 3.

Method 1; a method in which a hydrolyzable silane compound (S1) having a cyclic ether group alone or a mixture of a silane compound (S1) and another hydrolyzable silane compound is subjected to hydrolytic condensation to synthesize a polyorganosiloxane having a cyclic ether group in a side chain (hereinafter, also referred to as "polyorganosiloxane E"), and then the polyorganosiloxane E is reacted with a carboxylic acid having an amino group (hereinafter, also referred to as "amino group-containing carboxylic acid") to obtain a polyorganosiloxane having an amino group in a side chain, and further the obtained amino group-containing polyorganosiloxane is reacted with a carboxylic acid anhydride.

Method 2; a method in which a mixture of a hydrolyzable silane compound (S2) having an amino group and a silane compound (S1), or a mixture of a silane compound (S1) and a silane compound (S2) and another hydrolyzable silane compound is subjected to hydrolytic condensation to synthesize a polyorganosiloxane (hereinafter, also referred to as "polyorganosiloxane M") having an amino group and a cyclic ether group in a side chain, and the resulting polyorganosiloxane M is reacted with a carboxylic acid anhydride.

Method 3; a method in which polyorganosiloxane E is synthesized by hydrolytic condensation of a silane compound (S1) alone or a mixture of a silane compound (S1) and another hydrolyzable silane compound, and then polyorganosiloxane E is reacted with an amino group-containing carboxylic acid.

Among these, the method 1 is preferable in that a polymer having high solubility in a solvent and high heat resistance can be obtained easily.

As the silane compound (S1), a hydrolyzable silane compound having an oxetanyl group or an oxetanyl group can be preferably used. Specific examples thereof include: glycidoxymethyltrimethoxysilane, glycidoxymethyltriethoxysilane, 2-glycidoxyethyltrimethoxysilane, 2-glycidoxyethyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3, 4-epoxycyclohexyl) ethyltriethoxysilane, (meth) acrylic acid (3-ethyloxetan-3-yl) methyl group, (meth) acrylic acid (3-methyloxetan-3-yl) methyl group and the like. The silane compound (S1) may be used alone or in combination of two or more.

As the silane compound (S2), a hydrolyzable silane compound having a primary amino group or a secondary amino group can be preferably used. Specific examples thereof include: 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane and the like. Further, one kind of the silane compound (S2) may be used alone, or two or more kinds may be used in combination.

The other silane compound is not particularly limited, and is a silane compound other than the silane compounds (S1) and (S2), and examples thereof include: tetraalkoxysilane compounds such as tetramethoxysilane and tetraethoxysilane; alkoxy silane compounds containing an alkyl group or an aryl group such as methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane and dimethyldiethoxysilane; sulfur-containing alkoxysilane compounds such as 3-mercaptopropyltriethoxysilane and mercaptomethyltriethoxysilane;

unsaturated bond-containing alkoxysilane compounds such as 3- (meth) acryloyloxypropyltrimethoxysilane, 3- (meth) acryloyloxypropylmethyldimethoxysilane, 3- (meth) acryloyloxypropylmethyldiethoxysilane, and vinyltriethoxysilane; an alkoxysilane compound having an acid anhydride group such as trimethoxysilylpropyl succinic anhydride; nitrogen-containing alkoxysilane compounds such as N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, and 3-triethoxysilyl-N- (1, 3-dimethyl-butylene) propylamine. As the other silane compound, one of these may be used alone, or two or more of these may be used in combination.

Examples of the amino group-containing carboxylic acid include: 3-aminobenzoic acid, 4-aminocyclohexanecarboxylic acid, 3-aminocyclohexanecarboxylic acid, 6-amino-2-naphthoic acid, β -alanine, glycine, 3-aminocyclopentanecarboxylic acid, 5-aminopentanoic acid, 4-aminohydrocinnamic acid, 4-aminophenylacetic acid, 4- (aminomethyl) benzoic acid, and the like. As the amino group-containing carboxylic acid, one of these may be used alone, or two or more of these may be used in combination.

The carboxylic anhydride may have one acid anhydride group, and the remaining structure is not particularly limited. Examples of the carboxylic acid anhydride include: trimellitic anhydride, 4-nitrophthalic anhydride, 3-nitrophthalic anhydride, 4-ethynylphthalic anhydride, 4- (1-propynyl) phthalic anhydride, 4-phenylethynylphthalic anhydride, 4-methylphthalic anhydride, phthalic anhydride, maleic anhydride, succinic anhydride, itaconic anhydride, allylsuccinic anhydride, 1, 2-cyclohexanedicarboxylic anhydride, 1-cyclohexene-1, 2-dicarboxylic anhydride, cis-4-cyclohexene-1, 2-dicarboxylic anhydride, 5-norbornene-2, 3-dicarboxylic anhydride, o-carboxyphenylacetic acid (Homophthalic acid) anhydride, glutaric anhydride, 3-trimethoxysilylpropyl succinic anhydride, cyclohexane-1, 2, 4-tricarboxylic acid-1, 2-anhydride, and the like. As the carboxylic acid anhydride, one of these may be used alone, or two or more thereof may be used in combination.

(hydrolytic condensation reaction)

In methods 1 to 3, the hydrolytic condensation reaction using a hydrolyzable silane compound is carried out by reacting one or more hydrolyzable silane compounds with water, preferably in the presence of an appropriate catalyst and an organic solvent, as described above. In methods 1 and 3, the ratio of the silane compound (S1) to be used is preferably 5 mol% or more, and more preferably 10 mol% or more, based on the total amount of monomers used for synthesizing the polyorganosiloxane.

In method 2, the silane compound (S1) is used in a proportion of preferably 5 to 99 mol%, more preferably 10 to 95 mol%, based on the total amount of monomers used for synthesizing the polyorganosiloxane. The proportion of the silane compound (S2) used is preferably 0.5 to 50 mol%, more preferably 1 to 40 mol%, based on the total amount of monomers used for synthesizing the polyorganosiloxane.

In the hydrolysis condensation reaction, the proportion of water used is preferably 1 to 30 moles per 1 mole of the silane compound (total amount) used in the reaction. Examples of the catalyst to be used include acids, alkali metal compounds, organic bases, titanium compounds, and zirconium compounds. Among them, preferred are tertiary organic amines or quaternary organic amines, such as: tertiary organic amines such as triethylamine, tri-n-propylamine, tri-n-butylamine, pyridine, 4-dimethylaminopyridine and the like; quaternary organic amines such as tetramethylammonium hydroxide. The amount of the catalyst to be used is appropriately determined depending on the kind of the catalyst, reaction conditions such as temperature, and the like, and is preferably 0.01 to 3 times by mol based on the total amount of the silane compounds.

Examples of the organic solvent used in the hydrolysis-condensation reaction include hydrocarbons, ketones, esters, ethers, and alcohols. Specific examples of these include hydrocarbons such as toluene and xylene; examples of the ketone include methyl ethyl ketone, methyl isobutyl ketone, methyl-n-amyl ketone, diethyl ketone, and cyclohexanone; examples of the ester include ethyl acetate, butyl acetate, isoamyl acetate, propylene glycol monomethyl ether acetate, 3-methoxybutyl acetate, and ethyl lactate; examples of the ether include ethylene glycol dimethyl ether, ethylene glycol diethyl ether, tetrahydrofuran, and the like; examples of the alcohol include 1-hexanol, 4-methyl-2-pentanol, ethylene glycol monomethyl ether, and ethylene glycol monoethyl ether. Among these, it is preferable to use an organic solvent which is not water-soluble or hardly water-soluble. The amount of the organic solvent to be used is preferably 10 to 10,000 parts by mass based on 100 parts by mass of the total of the silane compounds used in the reaction.

The hydrolytic condensation reaction is preferably carried out by heating with an oil bath or the like. In this case, the heating temperature is preferably 130 ℃ or lower, and the heating time is preferably 0.5 to 12 hours. After the reaction is completed, the organic solvent layer separated from the reaction solution is dried with a drying agent as necessary, and then the solvent is removed, whereby the target polyorganosiloxane can be obtained. The method for synthesizing the polyorganosiloxane is not limited to the above-mentioned hydrolytic condensation reaction, and may be carried out by a method of reacting a hydrolyzable silane compound in the presence of oxalic acid and an alcohol, for example.

(reaction (1) of polyorganosiloxane E with amino group-containing carboxylic acid)

In method 1, a cyclic ether group of polyorganosiloxane E is reacted with a carboxyl group of an amino group-containing carboxylic acid to obtain polyorganosiloxane having an amino group in a side chain. The reaction is preferably carried out in the presence of a suitable catalyst and an organic solvent.

As the catalyst used in the reaction, for example, a hardening accelerator can be used in addition to the organic base which can be preferably used. Specific examples of these include primary organic amines, secondary organic amines, tertiary organic amines, quaternary organic amine salts, and the like; examples of the hardening accelerator include tertiary amines, imidazole derivatives, organic phosphorus compounds, quaternary phosphonium salts, diazabicycloalkenes, organometallic compounds, quaternary ammonium halides, metal halides, latent hardening accelerators, and the like. Examples of the latent hardening accelerator include: high melting point dispersion type latent curing accelerators (e.g., amine addition type accelerators), microcapsule type latent curing accelerators, amine salt type latent curing accelerators, high temperature dissociation type thermal cationic polymerization type latent curing accelerators, and the like. Among these, a quaternary organic amine salt or a quaternary ammonium halide is preferably used as the catalyst.

Specific examples of the catalyst include quaternary organic amine salts such as tetramethylammonium hydroxide; examples of the quaternary ammonium halide include tetraethylammonium bromide, tetra-n-butylammonium bromide, tetraethylammonium chloride, and tetra-n-butylammonium chloride. As the catalyst, one or more selected from these can be used. The proportion of the catalyst used is preferably 0.01 to 100 parts by mass, more preferably 0.1 to 20 parts by mass, relative to 100 parts by mass of polyorganosiloxane E.

Examples of the organic solvent used for the reaction of polyorganosiloxane E with carboxylic acid include: ketones, ethers, esters, amides, alcohols, and the like. Specific examples of the organic solvent include ketones such as methyl ethyl ketone, methyl isobutyl ketone, methyl-n-amyl ketone, diethyl ketone, cyclohexanone, and the like; examples of the ether include ethylene glycol dimethyl ether, ethylene glycol diethyl ether, tetrahydrofuran, dioxane, etc.;

examples of the ester include ethyl acetate, n-butyl acetate, isoamyl acetate, propylene glycol monomethyl ether acetate, 3-methoxybutyl acetate, and ethyl lactate; examples of the amide include formamide, N-methylformamide, N-dimethylformamide, N-ethylformamide, N-diethylformamide, acetamide, N-methylacetamide, N-dimethylacetamide, N-ethylacetamide, N-diethylacetamide, N-methylpropanamide, N-methylpyrrolidone, N-formylmorpholine, N-formylpiperidine, N-formylpyrrolidine, N-acetylmorpholine, N-acetylpiperidine, and N-acetylpyrrolidine;

examples of the alcohol include 1-hexanol, 4-methyl-2-pentanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol mono-n-butyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, and propylene glycol mono-n-propyl ether, and one or more selected from these can be used.

The use ratio of the organic solvent is preferably a ratio such that the total mass of the components other than the organic solvent in the reaction solution accounts for 0.1 to 50 mass%, more preferably 5 to 50 mass%, of the total amount of the reaction solution.

The proportion of the amino group-containing carboxylic acid to be used is appropriately set in accordance with the number of functional groups B introduced into the side chain of the polyorganosiloxane E, but is preferably 0.005 to 0.5 mol based on 1mol of the silane compound (total amount) used for the synthesis of the polyorganosiloxane, from the viewpoint of sufficiently obtaining the effect of improving the thermal reliability of the liquid crystal cell and the solvent resistance of the liquid crystal alignment film by the introduction of the functional groups B. The lower limit of the use ratio is more preferably 0.01 mol or more, and still more preferably 0.05 mol or more. The upper limit is more preferably 0.4 mol or less, and still more preferably 0.3mol or less.

In method 1, in the reaction of polyorganosiloxane E with an amino group-containing carboxylic acid, a carboxylic acid having a functional group (hereinafter, also referred to as "functional group-containing carboxylic acid") may be used in combination for the purpose of introducing a functional group (hereinafter, also referred to as "functional group") which imparts a desired function to the polymer into polyorganosiloxane E. When the functional group-containing carboxylic acid is used together with the amino group-containing carboxylic acid, the total use ratio of the functional group-containing carboxylic acids is preferably 0.05 to 0.8 mol, more preferably 0.1 to 0.7 mol, based on 1mol of the silane compound (total amount) used in the synthesis of the polyorganosiloxane, in order to introduce a sufficient amount of the functional group without inhibiting the introduction of the amino group.

The reaction of polyorganosiloxane E with the amino group-containing carboxylic acid is carried out at a temperature of preferably 0 to 200 ℃ and more preferably 50 to 150 ℃ for preferably 0.1 to 50 hours and more preferably 0.5 to 20 hours. After the reaction is completed, the organic solvent layer separated from the reaction solution is dried with a drying agent as necessary, and then the solvent is removed, whereby an amino group-containing polyorganosiloxane can be obtained.

(reaction of polyorganosiloxane with amino group and carboxylic anhydride)

In methods 1 and 2, an amino group of polyorganosiloxane and an acid anhydride group of carboxylic acid anhydride are reacted. Thus, a polyorganosiloxane having an epoxy group and a carboxyl group in a side chain can be obtained as the polymer [ P ].

From the viewpoint of sufficiently obtaining the effect of improving the thermal reliability of the liquid crystal cell and the solvent resistance of the liquid crystal alignment film by introducing the functional group B (here, a carboxyl group) into the polyorganosiloxane side chain, the proportion of the carboxylic anhydride to be used is preferably 0.1 to 2.0 moles per 1 mole of the amino groups (total amount) of the polyorganosiloxane. The lower limit of the use ratio is more preferably 0.2 mol or more, and still more preferably 0.3mol or more. The upper limit is more preferably 1.5 mol or less, and still more preferably 1.2 mol or less.

The reaction is preferably carried out in a suitable organic solvent. Examples of the organic solvent to be used include: aprotic polar solvents, phenolic solvents, alcohols, ketones, esters, ethers, halogenated hydrocarbons, and the like. Preferred examples of the organic solvent include at least one selected from the group consisting of N-methyl-2-pyrrolidone, N-dimethylacetamide, N-dimethylformamide, dimethyl sulfoxide, γ -butyrolactone, tetramethylurea, hexamethylphosphoric triamide, m-cresol, xylenol, and halogenated phenol.

In the reaction, the reaction temperature is preferably-20 ℃ to 100 ℃, and more preferably 0 ℃ to 80 ℃. The reaction time is preferably 1 to 48 hours, more preferably 2 to 12 hours. The obtained reaction solution may be directly used for the preparation of the liquid crystal aligning agent, or the polymer [ P ] contained in the reaction solution may be isolated by a known isolation method and then used for the preparation of the liquid crystal aligning agent.

(reaction (2) of polyorganosiloxane E with amino group-containing carboxylic acid)

In method 3, the cyclic ether group of polyorganosiloxane E is reacted with the amino group of the amino group-containing carboxylic acid. Thus, a polyorganosiloxane having an epoxy group and a carboxyl group in a side chain can be obtained as the polymer [ P ].

From the viewpoint of sufficiently obtaining the effect of improving the thermal reliability of the liquid crystal element and the solvent resistance of the liquid crystal alignment film by introducing the carboxyl group into the side chain of the polyorganosiloxane, the proportion of the amino group-containing carboxylic acid to be used is preferably 0.005 to 0.5 mol based on 1mol of the silane compound (total amount) used in the synthesis of the polyorganosiloxane. The lower limit of the use ratio is more preferably 0.01 mol or more, and still more preferably 0.05 mol or more. The upper limit is more preferably 0.4 mol or less, and still more preferably 0.3mol or less.

The reaction is optionally carried out in the presence of a suitable catalyst in a suitable solvent. Examples of the catalyst include: magnesium oxide, calcium oxide, potassium carbonate, and the like. The solvent is preferably one capable of uniformly dissolving or decomposing the amino group-containing polyorganosiloxane and the carboxylic acid anhydride, and examples thereof include N-methyl-2-pyrrolidone and tetrahydrofuran. In the reaction, the reaction temperature is preferably-20 ℃ to 180 ℃, and more preferably 10 ℃ to 120 ℃. The reaction time is preferably 1 to 72 hours, more preferably 2 to 48 hours. The resultant reaction solution can be subjected to isolation of the polymer [ P ] contained in the reaction solution by a known isolation method and then subjected to preparation of a liquid crystal aligning agent.

In the case of obtaining a polyorganosiloxane having a functional group as the polymer [ P ] in the methods 2 and 3, the polyorganosiloxane having a cyclic ether group may be reacted with the functional group-containing carboxylic acid before the polyorganosiloxane having an amino group is reacted with the carboxylic anhydride in the method 2, and the polyorganosiloxane having a cyclic ether group may be reacted with the functional group-containing carboxylic acid before the polyorganosiloxane is reacted with the amino group-containing carboxylic acid in the method 3. The following description of method 1 is applied to the reaction conditions of the polyorganosiloxane with a cyclic ether group and the carboxylic acid containing a functional group.

The following flow A1, flow A2, flow B and flow C show examples of the methods 1 to 3. In the method 1, when an epoxy group-containing silane compound is used as the silane compound (S1), 3-aminobenzoic acid is used as the amino group-containing carboxylic acid, and trimellitic anhydride is used as the carboxylic anhydride, the polymer [ P ] can be obtained by the following scheme A1 (beta cleavage of epoxy group) and scheme A2 (alpha cleavage of epoxy group).

[ solution 2]

[ solution 3]

(Process A1 and Process A)In 2, L ¹ Is a divalent linking group, R ¹ Being hydrogen atoms)

In the method 2, when an epoxy group-containing silane compound is used as the silane compound (S1) and trimellitic anhydride is used as the carboxylic anhydride, the polymer [ P ] can be obtained by the following scheme B.

[ solution 4]

(in scheme B, L ¹ And L ² Each independently is a divalent linking group)

In the method 3, in the case of using an epoxy group-containing silane compound as the silane compound (S1) and 4-aminobenzoic acid as the amino group-containing carboxylic acid, the polymer [ P ] can be obtained by the following scheme C.

[ solution 5]

(in scheme C, L ¹ Is a divalent linking group, R ³ Being hydrogen atoms)

According to the above-mentioned scheme A1, scheme A2 and scheme B, polyorganosiloxanes having a cyclic ether group (here, an oxetanyl group) and a carboxyl group, and polyorganosiloxanes having a cyclic ether group and an amino group can be obtained as the polymer [ P ]. Further, according to the above-mentioned scheme C, as the polymer [ P ], a polyorganosiloxane having a cyclic ether group and a carboxyl group can be obtained.

(functional group)

The polymer [ P ] preferably has a functional group in a side chain according to a driving mode of a liquid crystal element to be applied. For example, when the liquid crystal aligning agent is used for manufacturing a vertical alignment type or horizontal alignment type liquid crystal device, the polymer [ P ] preferably has an alignment-developing site for aligning liquid crystal molecules as a functional group. When a polymer film formed of a liquid crystal aligning agent is provided with liquid crystal aligning properties by a photo-alignment method, the polymer [ P ] preferably has a photo-alignment group as a functional group. In addition, in the case where the alignment regulating force of the liquid crystal molecules is increased by light irradiation from the outside of the liquid crystal cell after the liquid crystal cell is constructed, the polymer [ P ] preferably has a group containing a carbon-carbon unsaturated bond as a functional group.

[ site for showing orientation ]

The alignment-developing site is a group that can control the alignment direction of liquid crystal molecules in the liquid crystal layer in a polymer film formed using a liquid crystal aligning agent. Further, the alignment of the liquid crystal molecules can be controlled without irradiating the alignment-developing portion with light. Specific examples of the orientation-developing site include a group represented by the following formula (3).

[ solution 6]

(in the formula (3), R ^I Is a monovalent group formed by substituting at least one hydrogen atom of an alkyl group having 1 to 40 carbon atoms, a fluoroalkyl group having 1 to 40 carbon atoms, an alkyl group having 1 to 40 carbon atoms with a cyano group, a nitro group or a fluorine atom, or a hydrocarbon group having 17 to 51 carbon atoms and having a steroid skeleton. Z ^I Is a single bond, O-, COO-or OCO- (wherein the bond attached with R is ^I Side). R ^II Is cyclohexylene or phenylene, and the hydrogen atom bonded to the ring may be substituted by cyano group, nitro group, fluorine atom, trifluoromethyl group or alkyl group having 1 to 3 carbon atoms. n1 is 1 or 2, and when n1 is 2, two R are ^II May be the same or different from each other. n2 is 0 or 1.Z is a linear or branched member ^II Is a single bond, O-, COO-or OCO- (wherein the bond attached with R is ^II Side). n3 is an integer of 0 to 2, and n4 is 0 or 1. Wherein, in the case of n2=0 and n4=0, R ^I Carbon number of 4 or more)

As "- (R) in said formula (3) ^II ) _n1 Examples of the divalent group represented by-include 1, 4-phenylene, 1, 4-cyclohexylene, 4 '-biphenylene, 4' -dicyclohexylene and the following formulas

[ solution 7]

(wherein a bond with "+" is bonded to Z ^I Bond)

The groups represented by each of the above groups are preferable as divalent groups.

[ photo-alignment group ]

The photo-alignment group is a functional group that imparts anisotropy to the film by a photo-isomerization reaction, a photo-dimerization reaction, a photo-decomposition reaction, or a photo-fries rearrangement reaction caused by light irradiation. Specific examples of the photo-alignment group include an azobenzene-containing group having azobenzene or a derivative thereof as a basic skeleton, a cinnamic acid-containing group having cinnamic acid or a derivative thereof (cinnamic acid structure) as a basic skeleton, a chalcone-containing group having chalcone or a derivative thereof as a basic skeleton, a benzophenone-containing group having benzophenone or a derivative thereof as a basic skeleton, a coumarin-containing group having coumarin or a derivative thereof as a basic skeleton, and a cyclobutane-containing group having cyclobutane or a derivative thereof as a basic skeleton. Among them, a group having a cinnamic acid structure represented by the following formula (5) is preferable in terms of high sensitivity to light or easy introduction into a polymer side chain. The polymer [ P ] is preferable in that the high-speed response of the obtained liquid crystal element can be improved by having a pretilt angle developing site together with the structure represented by the following formula (5).

[ solution 8]

( In the formula (5), R is a fluorine atom or a cyano group. a' is an integer of 0 to 4. When a 'is 2 or more, a plurality of R's may be the same or different. "" indicates a bond )

[ group containing carbon-carbon unsaturated bond ]

Examples of the group containing a carbon-carbon unsaturated bond include a group represented by the following formula (4).

[ solution 9]

(in the formula (4), R is a hydrogen atom or a methyl group, X ^I And X ^II Respectively 1, 4-phenylene and alkanediyl group having 1 to 8 carbon atoms, and Z is an oxygen atom, -COO-, or-OCO- (wherein a bond having "-" is attached to X ^II A, b, c, and d are each 0 or 1. Wherein, when c is 0 and d is 1, X ^II Is 1, 4-phenylene, c is 0 when b is 0)

Specific examples of the group represented by the formula (4) include: vinyl, allyl, p-vinylphenyl, (meth) acryloyloxyalkyl, 4- ((meth) acryloyloxyalkyl) phenyl, ((meth) acryloyloxyphenyl) alkyl, 4- ((meth) acryloyloxyalkyl) phenyl, (meth) acryloyloxyalkyl, 6- { [6- (acryloyloxy) hexanoyl ] oxy } hexyl and the like.

When the polymer [ P ] is a polymer having a functional group in a side chain, examples of the polymer include (I) a method of synthesizing the polymer by polymerization using a monomer having a functional group, and (II) a method of introducing the polymer [ P ] or its precursor into a side chain by utilizing a cyclic ether group. Among these, the compound (II) is preferable in that the introduction rate of the functional group can be easily adjusted. Among them, it is preferable to produce the polyorganosiloxane having a cyclic ether group (polyorganosiloxane E in methods 1 and 3, polyorganosiloxane M in method 2) by reacting with a compound having a functional group B and a functional group (hereinafter, also referred to as "side chain precursor [ C ]").

The polymer [ P ] may have only one of an orientation-exhibiting site, a photo-orientation group, and a group containing a carbon-carbon unsaturated bond as a functional group, or may have a plurality of types. In the case where the polymer [ P ] has a plurality of such functional groups, one functional group and the other functional group may be present in the same side chain or may be present in different side chains. In addition, all of the functional groups may be contained in a single kind of polymer, or may be used as a mixture of a polymer having a part of the desired functional groups and a polymer having the remaining functional groups. Of course, three or more polymers may be used in combination as the polymer [ P ], and two or more polymers having the same functional group may be used in combination. Since any method is possible, the polymer [ P ] may be used as long as each functional group is contained in a single substance or a mixture as a whole.

The weight average molecular weight (Mw) of the polymer [ P ] in terms of polystyrene as measured by Gel Permeation Chromatography (GPC) is preferably 1,000 to 300,000, more preferably 2,000 to 100,000. When the polymer [ P ] is a modified polymer modified with a compound having a functional group, the weight-average molecular weight of the polymer before modification is preferably within the above range. The molecular weight distribution (Mw/Mn) represented by the ratio of Mw to the number average molecular weight (Mn) in terms of polystyrene measured by GPC is preferably 5 or less, more preferably 4 or less. The polymer [ P ] used for the preparation of the liquid crystal aligning agent may be only one kind, or two or more kinds may be combined.

In terms of sufficiently obtaining the effect of improving the thermal reliability of the obtained liquid crystal cell, the content ratio of the polymer [ P ] in the liquid crystal aligning agent is preferably 0.1 part by mass or more, more preferably 0.5 part by mass or more, and further preferably 1 part by mass or more, relative to 100 parts by mass of all the polymers contained in the liquid crystal aligning agent. When another polymer is blended, the content of the polymer [ P ] is preferably 50 parts by mass or less, more preferably 25 parts by mass or less, and still more preferably 20 parts by mass or less, based on 100 parts by mass of the other polymer contained in the liquid crystal aligning agent.

< other ingredients >

The liquid crystal aligning agent of the present disclosure contains the polymer [ P ] as described above, but may contain other components shown below as needed.

(other Polymer)

The liquid crystal aligning agent of the present disclosure may contain a polymer (hereinafter, also referred to as "other polymer") different from the polymer [ P ] for the purpose of obtaining an effect of improving various performances such as electrical characteristics, liquid crystal alignment properties, reliability, or the like, or achieving cost reduction, or the like. The main skeleton of the other polymer is not particularly limited. Examples of the other polymer include polymers having a main skeleton of polyamide acid, polyimide, polyamic acid ester, polyamide, polyorganosiloxane other than polymer [ P ], polyester, cellulose derivative, polyacetal, polystyrene derivative, poly (styrene-phenylmaleimide) derivative, poly (meth) acrylate, and the like. In the present specification, "(meth) acrylate" means that acrylate and methacrylate are included.

From the viewpoint of electrical characteristics, affinity for liquid crystal, mechanical strength, affinity for the polymer [ P ], and the like, it is preferable to use at least one polymer selected from the group consisting of polyamic acids, polyamic acid esters, polyimides, and polymers of monomers having a polymerizable unsaturated bond (hereinafter, also referred to as "polymer [ Q").

The blending ratio of the polymer [ Q ] is preferably 100 parts by mass or more, more preferably 100 to 2000 parts by mass, and still more preferably 200 to 1500 parts by mass, based on 100 parts by mass of the polymer [ P ] used for producing the liquid crystal aligning agent.

(Polyamic acid, polyamic acid ester and polyimide)

The polyamic acid, polyamic acid ester, and polyimide contained in the liquid crystal aligning agent can be synthesized according to a conventionally known method. For example, the polyamic acid can be obtained by reacting tetracarboxylic dianhydride with diamine. The polyamic acid ester can be obtained, for example, by a method of reacting a polyamic acid with an esterifying agent (for example, methanol, ethanol, N-dimethylformamide diethyl acetal, or the like). The polyimide can be obtained, for example, by subjecting a polyamic acid to dehydration ring closure and imidization. The polyimide preferably has an imidization ratio of 20 to 95%, more preferably 30 to 90%. The imidization ratio is a ratio of the number of imide ring structures to the total of the number of amic acid structures and the number of imide ring structures of the polyimide expressed as a percentage.

Examples of tetracarboxylic acids used in the polymerization include: aliphatic tetracarboxylic acid dianhydrides such as butane tetracarboxylic acid dianhydride and ethylenediamine tetraacetic acid dianhydride; 1,2,3, 4-cyclobutanetetracarboxylic dianhydride, 1, 3-dimethyl-1, 2,3, 4-cyclobutanetetracarboxylic dianhydride, 2,3, 5-tricarboxycyclopentylacetic dianhydride, 5- (2, 5-dioxotetrahydrofuran-3-yl) -3a,4,5,9 b-tetrahydronaphthalene [1,2-c ] furan-1, 3-dione, 5- (2, 5-dioxotetrahydrofuran-3-yl) -8-methyl-3a, 4,5,9 b-tetrahydronaphthalene [1,2-c ] furan-1, 3-dione, 2,4,6, 8-tetracarboxybicyclo [3.3.0] octane-2, 4, 6-tetracarboxylic dianhydride, 8-cyclopentanetetracarboxylic dianhydride, cyclohexanetetracarboxylic dianhydride, or the like alicyclic tetracarboxylic dianhydride; other than aromatic tetracarboxylic dianhydrides such as pyromellitic dianhydride, 4,4' - (hexafluoroisopropylidene) diphthalic anhydride, p-phenylenebis (trimellitic acid monoester anhydride), ethyleneglycol bis (trimellitic anhydride), and 1, 3-propyleneglycolbis (trimellitic anhydride), tetracarboxylic dianhydrides described in japanese unexamined patent publication No. 2010-97188 can be used. Further, the tetracarboxylic dianhydride may be used alone or in combination of two or more.

Examples of the diamine used in the polymerization include: aliphatic diamines such as ethylenediamine and tetramethylenediamine; alicyclic diamines such as p-cyclohexanediamine and 4,4' -methylenebis (cyclohexylamine); hexadecyloxydiaminobenzene, cholestanyloxydiaminobenzene, cholestanyl diaminobenzoate, cholesteryl ester of diaminobenzoate, lanostanyl ester of diaminobenzoate, 3, 6-bis (4-aminobenzoyloxy) cholestane, 3, 6-bis (4-aminophenoxy) cholestane, 1-bis (4- ((aminophenyl) methyl) phenyl) -4-butylcyclohexane, 2, 5-diamino-N, N-diallylaniline, the following formulae (8-1) to (8-3)

[ solution 10]

Side chain type aromatic diamines such as the compounds represented by the above formulae; p-phenylenediamine, 4' -diaminodiphenylmethane, 4' -diaminodiphenylamine, 4-aminophenyl-4 ' -aminobenzoate, 4' -diaminoazobenzene, 3, 5-diaminobenzoic acid, 1, 5-bis (4-aminophenoxy) pentane, bis [2- (4-aminophenyl) ethyl ] adipic acid, bis (4-aminophenyl) amine, N-bis (4-aminophenyl) methylamine, N, aromatic diamines of non-side chain type such as N ' -bis (4-aminophenyl) -benzidine, 2' -dimethyl-4, 4' -diaminobiphenyl, 2' -bis (trifluoromethyl) -4,4' -diaminobiphenyl, 4' -diaminodiphenyl ether, 2-bis [4- (4-aminophenoxy) phenyl ] propane, 4' - (phenylenediisopropylidene) dianiline, 1, 4-bis (4-aminophenoxy) benzene, 4- (4-aminophenoxycarbonyl) -1- (4-aminophenyl) piperidine, and 4,4' - [4,4' -propane-1, 3-diylbis (piperidine-1, 4-diyl) ] diphenylamine; diaminoorganosiloxanes such as 1,3-bis (3-aminopropyl) -tetramethyldisiloxane, and diamines described in JP 2010-97188A may be used. Further, one diamine may be used alone, or two or more diamines may be used in combination.

The polyamic acid, polyamic acid ester, and polyimide contained in the liquid crystal alignment agent preferably have a weight average molecular weight (Mw) in terms of polystyrene measured by GPC of 1,000 to 500,000, more preferably 2,000 to 300,000. The molecular weight distribution (Mw/Mn) is preferably 7 or less, more preferably 5 or less. The polyamic acid, polyamic acid ester, and polyimide contained in the liquid crystal alignment agent may be one kind alone, or two or more kinds may be combined.

(Polymer of monomer having polymerizable unsaturated bond)

As for the polymer of the monomer having a polymerizable unsaturated bond (hereinafter, also referred to as "polymer PAc"), examples of the polymerizable unsaturated bond of the monomer constituting the polymer PAc include: (meth) acryloyl, vinyl, styryl, maleimido, and the like. Specific examples of the monomer having such a polymerizable unsaturated bond include: (meth) acrylic compounds such as unsaturated carboxylic acids, unsaturated carboxylic acid esters, and unsaturated polycarboxylic acid anhydrides; aromatic vinyl compounds such as styrene, methylstyrene and divinylbenzene; conjugated diene compounds such as 1, 3-butadiene and 2-methyl-1, 3-butadiene; maleimide compounds such as N-methylmaleimide, N-cyclohexylmaleimide and N-phenylmaleimide. The monomers having a polymerizable unsaturated bond may be used singly or in combination of two or more.

The polymer PAc is preferably a poly (meth) acrylate. The poly (meth) acrylate may be a polymer containing only a (meth) acrylic compound, or may be a polymer containing a (meth) acrylic compound and another monomer. As the other monomers, there may be mentioned: conjugated diene compounds, aromatic vinyl compounds, maleimide compounds, and the like. The poly (meth) acrylate preferably has 30% by mass or more of a structural unit derived from a (meth) acrylic compound, more preferably 40% by mass or more, still more preferably 50% by mass or more, and particularly preferably 70% by mass or more.

The (meth) acrylic compound used in the polymerization is not particularly limited, and specific examples thereof include unsaturated carboxylic acids such as (meth) acrylic acid, α -ethylacrylic acid, maleic acid, fumaric acid, itaconic acid, vinyl benzoic acid, and the like;

examples of the unsaturated carboxylic acid ester include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, allyl (meth) acrylate, cyclohexyl (meth) acrylate, and tricyclo [5.2.1.0 ] meth) acrylate ^2,6 ]Decyl-8-yl, dicyclopentyl (meth) acrylate, benzyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, trimethoxysilylpropyl (meth) acrylate, 2-trifluoroethyl (meth) acrylate, 2, 3-pentafluoropropyl (meth) acrylate, methoxyethyl (meth) acrylate, N (meth) acrylate, N-dimethylaminoethyl ester, methoxypolyethylene glycol (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, glycidyl (meth) acrylate, 3, 4-epoxycyclohexylmethyl (meth) acrylate, 3, 4-epoxybutyl (meth) acrylate, 4-hydroxybutyl glycidyl acrylate, and the like;

examples of the unsaturated polycarboxylic acid anhydride include maleic anhydride, itaconic anhydride, and cis-1, 2,3, 4-tetrahydrophthalic anhydride. Further, the (meth) acrylic compound may be used singly or in combination of two or more of these.

The polymerization reaction using the (meth) acrylic compound is preferably performed by radical polymerization. As the polymerization initiator used in the polymerization reaction, for example, azo compounds such as 2,2' -azobis (isobutyronitrile), 2' -azobis (2, 4-dimethylvaleronitrile), and 2,2' -azobis (4-methoxy-2, 4-dimethylvaleronitrile) can be preferably used. The proportion of the polymerization initiator used is preferably 0.01 to 40 parts by mass relative to 100 parts by mass of the total monomers used in the reaction.

The polymerization reaction of the (meth) acrylic compound is preferably carried out in an organic solvent. Examples of the organic solvent used in the reaction include: alcohols, ethers, ketones, amides, esters, hydrocarbon compounds, and the like. Among these, at least one selected from the group consisting of alcohols and ethers is preferably used, and partial ethers of polyhydric alcohols are more preferably used. Preferred specific examples thereof include: diethylene glycol methyl ethyl ether, propylene glycol monomethyl ether acetate, and the like. As the organic solvent, one of these solvents may be used alone or two or more of these solvents may be used in combination.

In the polymerization reaction of the (meth) acrylic compound, the reaction temperature is preferably 30 to 120 ℃ and the reaction time is preferably 1 to 36 hours. The amount (a) of the organic solvent used is preferably such that the total amount (b) of the monomers used in the reaction is 0.1 to 50% by mass relative to the total amount (a + b) of the reaction solution.

The number average molecular weight (Mn) in terms of polystyrene measured by GPC on a poly (meth) acrylate is preferably 250 to 500,000, more preferably 500 to 100,000, and still more preferably 1,000 to 50,000.

Examples of the other components other than the above include: a compound having at least one epoxy group in the molecule (except for the compound corresponding to the silicon-containing compound [ A ]), a functional silane compound (except for the compound corresponding to the silicon-containing compound [ A ]), an antioxidant, a metal chelate compound, a hardening accelerator, a crosslinking agent, a surfactant, a filler, a dispersant, a photosensitizer, and the like. The blending ratio of the other components may be appropriately selected depending on each compound within a range not impairing the effects of the present disclosure.

(solvent)

The liquid crystal aligning agent of the present disclosure is prepared as a composition in which a polymer component and optionally formulated components are preferably dissolved or dispersed in an organic solvent to form a solution. Examples of the organic solvent to be used include: aprotic polar solvents, phenolic solvents, alcohols, ketones, esters, ethers, halogenated hydrocarbons, and the like. The solvent component may be one of these solvents, or may be a mixed solvent of two or more of these solvents.

Specific examples of the organic solvent to be used include: n-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 1, 2-dimethyl-2-imidazolidinone, γ -butyrolactone, γ -butyrolactam, N-dimethylformamide, N-dimethylacetamide, 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 (butyl cellosolve), 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, diethylene glycol monoethyl ether acetate, diisobutyl ketone, isopentyl propionate, isopentyl isobutyrate, diisoamyl ether, ethylene carbonate, propylene carbonate, cyclohexane, octanol, tetrahydrofuran, and the like. The hydrocarbon solvent not containing an amide structure may be used for the purpose of application to a plastic substrate or low-temperature calcination.

The solvent component is preferably at least one selected from the group consisting of compounds represented by the following formulae (E-1) to (E-5) and a solvent (hereinafter, also referred to as "specific solvent") having a boiling point of 180 ° or less at 1 atm. These specific solvents are preferable in that the coating property (printability) of the liquid crystal aligning agent is good and a liquid crystal element having excellent liquid crystal aligning property and electric characteristics can be obtained even when the liquid crystal aligning agent is heated at low temperature (for example, 200 ℃ or lower) during film formation.

[ solution 11]

(in the formula (E-1), R ⁴¹ Is alkyl or CH with 1 to 4 carbon atoms ₃ CO-，R ⁴² Is alkanediyl having 1 to 4 carbon atoms or- (R) ⁴⁷ -O)r-R ⁴⁸ - (wherein, R) ⁴⁷ And R ⁴⁸ Each independently is an alkanediyl group having 2 or 3 carbon atoms, R is an integer of 1 to 4), R ⁴³ Is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms)

[ solution 12]

(in the formula (E-2), R ⁴⁴ An alkanediyl group having 1 to 4 carbon atoms)

[ solution 13]

(in the formula (E-3), R ⁴⁵ And R ⁴⁶ Each independently an alkyl group having 1 to 8 carbon atoms)

[ solution 14]

R ⁴⁹ -R ⁵⁰ -OH (E-4)

(in the formula (E-4), R ⁴⁹ Is a hydrogen atom or a hydroxyl group, in R ⁴⁹ In the case of a hydrogen atom, R ⁵⁰ Is a hydrocarbon group having 1 to 9 carbon atoms, in which R ⁴⁹ In the case of hydroxy, R ⁵⁰ Is a divalent hydrocarbon group having 1 to 9 carbon atoms or a divalent group having an oxygen atom between the carbon-carbon bonds)

[ chemical 15]

R ⁵¹ -COO-R ⁵² (E-5)

(in the formula (E-5), R ⁵¹ And R ⁵² Each independently is a monovalent hydrocarbon group having 1 to 6 carbon atoms or the carbon-carbon bondMonovalent radicals having oxygen atoms)

Specific examples of the specific solvent include propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol methyl ethyl ether, 3-methoxy-1-butanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monopropyl ether, ethylene glycol-n-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, and the like;

examples of the compound represented by the formula (E-2) include cyclobutanone, cyclopentanone, cyclohexanone;

examples of the compound represented by the formula (E-3) include acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, diethyl ketone, methyl-isobutyl ketone, methyl-n-amyl ketone, ethyl-n-butyl ketone, methyl-n-hexyl ketone, di-isobutyl ketone, trimethylnonanone, cyclopentanone, cyclohexanone, cycloheptanone, cyclooctanone, methylcyclohexanone, 2, 4-pentanedione, acetonylacetone, diisobutyl ketone, and the like;

examples of the compound represented by the formula (E-4) include methanol, ethanol, propanol, butanol, pentanol, 3-methoxybutanol, hexanol, heptanol, octanol, furfuryl alcohol, phenol, cyclohexanol, methylcyclohexanol, 3, 5-trimethylcyclohexanol, benzyl alcohol, diacetone alcohol and other mono-alcohols, and ethylene glycol, 1, 2-propylene glycol, 1, 3-butanediol, 2, 4-pentanediol and other polyhydric alcohols;

examples of the compound represented by the formula (E-5) include partial ethers of polyhydric alcohols (for example, partial ethers of polyhydric alcohols such as ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether, ethylene glycol mono-2-ethylbutyl ether, diethylene glycol monomethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monopropyl ether, etc.), methyl acetate, ethyl acetate, propyl acetate, n-butyl acetate, isobutyl acetate, t-butyl acetate, 3-methoxybutyl acetate, 2-ethylhexyl acetate, methyl acetoacetate, ethyl acetoacetate, ethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monopropyl ether acetate, dipropylene glycol monomethyl ether acetate, diethylene glycol, methoxytriethylene glycol acetate, ethyl propionate, n-butyl propionate, di-n-butyl oxalate, methyl lactate, ethyl lactate, n-butyl lactate, n-pentyl lactate, diethyl malonate, dimethyl phthalate, etc. One kind of the specific solvent may be used alone, or two or more kinds may be used in combination.

The use ratio of the specific solvent is preferably 10% by mass or more, more preferably 20% by mass or more, and still more preferably 50% by mass or more, relative to the total amount of the solvents used for producing the liquid crystal aligning agent. The upper limit of the use ratio of the specific solvent is preferably 95% by mass or less, more preferably 90% by mass or less, and still more preferably 80% by mass or less, relative to the total amount of the solvents used for producing the liquid crystal aligning agent.

The concentration of the solid component in the liquid crystal aligning agent (the ratio of the total mass of the components other than the solvent of the liquid crystal aligning agent to the total mass of the liquid crystal aligning agent) is appropriately selected in consideration of viscosity, volatility, and the like, and is preferably in the range of 1 to 10 mass%. When the solid content concentration is less than 1% by mass, the film thickness of the coating film becomes too small to obtain a good liquid crystal alignment film. On the other hand, when the solid content concentration exceeds 10 mass%, the film thickness of the coating film becomes too large to obtain a good liquid crystal alignment film, and the viscosity of the liquid crystal alignment agent tends to increase to lower the coatability.

< liquid Crystal alignment film and liquid Crystal element >

The liquid crystal alignment film of the present disclosure is formed of the liquid crystal alignment agent prepared in the manner described. The liquid crystal element of the present disclosure includes a liquid crystal alignment film formed using the liquid crystal alignment agent described above. The operation mode of the liquid crystal In the liquid crystal element is not particularly limited, and can be applied to various modes such as TN type, STN type, VA type (including Vertical Alignment-Multi-domain Vertical Alignment (VA-MVA) type, vertical Alignment-pattern Vertical Alignment (VA-PVA) type, etc.), IPS (In-Plane Switching) type, FFS (Fringe Field Switching) type, optically Compensated Bend (OCB), polymer Sustained Alignment (PSA) type, and the like. The liquid crystal element can be manufactured by a method including, for example, the following steps 1 to 3. In step 1, the substrate is used differently depending on the desired operation mode. The operation modes in step 2 and step 3 are common.

< step 1: formation of coating film

First, a liquid crystal aligning agent is applied to a substrate, and preferably, the coated surface is heated, thereby forming a coating film on the substrate. Examples of the substrate include glass such as float glass and soda glass; transparent substrates comprising plastics such as polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polycarbonate, and poly (alicyclic olefin). As the transparent conductive film provided on one surface of the substrate, a transparent conductive film containing tin oxide (SnO) can be used ₂ ) A film of (Nesa) (registered trademark of PPG Corp., USA) containing indium oxide-tin oxide (In) ₂ O ₃ -SnO ₂ ) An Indium Tin Oxide (ITO) film of (a). In the case of manufacturing a TN type, STN type, or VA type liquid crystal element, two substrates provided with a patterned transparent conductive film are used. On the other hand, in the case of manufacturing an IPS-type or FFS-type liquid crystal element, a substrate provided with electrodes patterned into a comb-tooth shape and an opposing substrate provided with no electrodes are used. The liquid crystal aligning agent is preferably applied to the substrate by a lithographic method, a flexographic method, a spin coating method, a roll coater method or an ink jet method on the electrode formation surface.

After the liquid crystal alignment agent is applied, it is preferable to perform preliminary heating (prebaking) for the purpose of preventing dripping of the applied liquid crystal alignment agent, and the like. The pre-baking temperature is preferably 30-200 ℃, and the pre-baking time is preferably 0.25-10 minutes. Thereafter, a calcination (post-baking) step is carried out for the purpose of completely removing the solvent and, if necessary, thermally imidizing the amic acid structure present in the polymer. In this case, the calcination temperature (post-baking temperature) is preferably 80 to 300 ℃, and the post-baking time is preferably 5 to 200 minutes. The film thickness of the film formed in this manner is preferably 0.001 to 1 μm.

< step 2: orientation treatment

In the case of producing a TN-type, STN-type, IPS-type, or FFS-type liquid crystal cell, the coating film formed in step 1 is subjected to a treatment (alignment treatment) for imparting liquid crystal alignment properties. This imparts alignment of the liquid crystal molecules to the coating film to form a liquid crystal alignment film. As the alignment treatment, there can be mentioned: rubbing treatment for imparting liquid crystal alignment energy to a coating film by rubbing the coating film in a certain direction with a roller wrapped with a cloth containing fibers such as nylon, rayon, cotton, and the like; and photo-alignment treatment for applying liquid crystal alignment energy to the coating film formed on the substrate by irradiating the coating film with light. On the other hand, in the case of producing a vertical alignment type liquid crystal element, the coating film formed in the step 1 may be used as it is as a liquid crystal alignment film, but the coating film may be subjected to an alignment treatment.

The light irradiation for photo-alignment can be performed by a method of irradiating the coating film after the post-baking step, a method of irradiating the coating film after the pre-baking step and before the post-baking step, a method of irradiating the coating film during heating of the coating film in at least any one of the pre-baking step and the post-baking step, or the like. As the radiation to be irradiated to the coating film, for example, ultraviolet rays and visible rays including light having a wavelength of 150nm to 800nm can be used. Preferably, the ultraviolet light contains light having a wavelength of 200nm to 400 nm. When the radiation is polarized light, the radiation may be linearly polarized light or partially polarized light. When the radiation used is linearly polarized light or partially polarized light, the irradiation may be performed from a direction perpendicular to the substrate surface, from an oblique direction, or a combination thereof. The irradiation direction in the case of unpolarized radiation is set to be an oblique direction.

Examples of the light source used include a low-pressure mercury lamp, a high-pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, and an excimer laser. The irradiation dose of the radiation is preferably 400J/m ² ～50,000J/m ² More preferably 1,000J/m ² ～20,000J/m ² . After the irradiation with light for imparting alignment energy, a treatment of cleaning the surface of the substrate with, for example, water, an organic solvent (for example, methanol, isopropyl alcohol, 1-methoxy-2-propanol acetate, butyl cellosolve, ethyl lactate, or the like) or a mixture of these, or a treatment of heating the substrate may be performed.

< step 3: construction of liquid Crystal cell

Two substrates on which liquid crystal alignment films are formed in this manner are prepared, and liquid crystal is disposed between the two substrates disposed opposite to each other, thereby manufacturing a liquid crystal cell. In the production of a liquid crystal cell, for example, there are: a method of arranging two substrates in opposition to each other with a gap therebetween so that liquid crystal alignment films are opposed to each other, bonding peripheral portions of the two substrates together with a sealant, injecting and filling liquid crystal into a cell gap surrounded by the surfaces of the substrates and the sealant, and sealing an injection hole; a method using an ODF (one drop filling) method, and the like. As the sealant, for example, an epoxy resin containing a curing agent and alumina balls as spacers can be used. The liquid crystal includes nematic liquid crystal and smectic liquid crystal, and among them, nematic liquid crystal is preferable. In the PSA mode (including a case where a compound having a polymerizable group (low-molecular or polymer) is contained in a liquid crystal alignment film), after a liquid crystal cell is constructed, a treatment of irradiating the liquid crystal cell with light while applying a voltage between conductive films provided on a pair of substrates is performed.

Then, a polarizing plate is attached to the outer surface of the liquid crystal cell as necessary to produce a liquid crystal element. Examples of the polarizing plate include a polarizing plate in which a polarizing film called an "H film" in which iodine is absorbed while polyvinyl alcohol is stretched and oriented, is sandwiched between cellulose acetate protective films, and a polarizing plate including an H film itself.

The liquid crystal element of the present disclosure can be effectively applied to various applications, for example, various display devices such as a timepiece, a portable game machine, a word processor, a notebook Personal computer, a car navigation system, a video camera, a Personal Digital Assistant (PDA), a Digital camera, a mobile phone, a smart phone, various monitors, a liquid crystal television, and an information display, and a light adjusting film. In addition, a liquid crystal element formed using the liquid crystal aligning agent of the present disclosure can also be applied to a retardation film.

Examples

The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

In this example, the weight average molecular weight Mw, the number average molecular weight (Mn), and the molecular weight distribution (Mw/Mn) of the polymer were measured by the following methods.

< weight average molecular weight (Mw), number average molecular weight (Mn) and molecular weight distribution (Mw/Mn) >)

Mw and Mn were measured by Gel Permeation Chromatography (GPC) under the following conditions. The molecular weight distribution (Mw/Mn) was calculated from the Mw and Mn thus obtained.

The device comprises the following steps: showa electrician (thigh) "GPC-101"

GPC column: "GPC-KF-801", "GPC-KF-802", "GPC-KF-803", and "GPC-KF-804" manufactured by Shimadzu GLC (Strand)

Mobile phase: tetrahydrofuran (THF)

Temperature of the pipe column: 40 deg.C

Flow rate: 1.0 mL/min

Sample concentration: 1.0% by mass

Sample injection amount: 100 μ L

A detector: differential refractometer

Standard substance: monodisperse polystyrene

< Synthesis of Polymer >

[ example 1A ]

Polymer (P-1) was synthesized according to the following scheme 1.

[ chemical 16]

A1000 ml three-necked flask was charged with 100.0g of 2- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, 500g of methyl isobutyl ketone and 10.0g of triethylamine, and mixed at room temperature. Then, after 100g of deionized water was added dropwise over 30 minutes from the addition funnel, mixed under reflux and reacted at 80 ℃ for 6 hours. After the reaction was completed, the organic layer was taken out, washed with a 0.2 mass% ammonium nitrate aqueous solution until the washed water became neutral, and then the solvent and water were distilled off under reduced pressure. Methyl isobutyl ketone was added in an appropriate amount to obtain a 50 mass% solution of polyorganosiloxane (E-1) having an epoxy group.

A500 ml three-necked flask was charged with 26.69g (0.3 mol equivalent) of the side chain precursor (ca-1), 3.09g (0.1 mol equivalent) of m-aminobenzoic acid, 2.00g of tetrabutylammonium bromide, 80g of a solution containing polyorganosiloxane (E-1), and 239g of methyl isobutyl ketone, and stirred at 110 ℃ for 4 hours. After cooling to room temperature, the liquid-separation washing operation was repeated 10 times with distilled water. Thereafter, the organic layer was recovered, and concentration and dilution with NMP were repeated 2 times by a rotary evaporator to obtain a 15 mass% NMP solution of the polymer (P-1) intermediate. After 0.44g (0.1 mol equivalent) of trimellitic anhydride was added to 50g of the intermediate solution, the solution was prepared using NMP so that the solid content concentration became 10 mass%, and then stirred at room temperature for 4 hours to obtain a NMP solution of the polymer (P-1).

Example 2A to example 12A and comparative Synthesis examples 1 to 4

Polymerization was carried out in the same manner as in example 1A except that the kinds and amounts of the compounds used in the synthesis were changed to those shown in Table 1 below, whereby polymers (P-2) to (P-12) and polymers (R-1) to (R-4) were obtained.

[ Table 1]

The values in table 1 represent the use ratio (mol%) of carboxylic acid and carboxylic acid anhydride to the number of epoxy groups in the epoxy group-containing polyorganosiloxane. The abbreviations for the compounds in table 1 are as follows.

(side chain precursor [ C ])

ca-1 to ca-5: compounds represented by the following formulae (ca-1) to (ca-5)

[ solution 17]

(amino group-containing carboxylic acid)

cb-1: 3-aminobenzoic acid

cb-2: 4-aminobenzoic acid

(Carboxylic anhydride)

an-1: trimellitic anhydride

an-2: 4-Nitrophthalic anhydride

an-3: 4-ethynylphthalic anhydride

an-4: maleic anhydride

an-5: cyclohexane-1, 2, 4-tricarboxylic acid-1, 2-anhydride

[ example 13A ]

Polymer (P-13) was synthesized according to scheme 2 below.

[ solution 18]

A1000 ml three-necked flask was charged with 90.0g of 2- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, 7.3g of 3-aminopropyltrimethoxysilane, 500g of methyl isobutyl ketone and 10.0g of triethylamine, and mixed at room temperature. Then, after 100g of deionized water was added dropwise over 30 minutes from the addition funnel, the mixture was mixed under reflux and the reaction was carried out at 80 ℃ for 6 hours. After the reaction was completed, the organic layer was taken out, washed with a 0.2 mass% ammonium nitrate aqueous solution until the washed water became neutral, and then the solvent and water were distilled off under reduced pressure. Methyl isobutyl ketone was added in an appropriate amount to obtain a 50 mass% solution of polyorganosiloxane (E-2) having an epoxy group and an amino group.

A500 ml three-necked flask was charged with 26.69g (0.3 mol equivalent) of the side chain precursor (ca-1), 2.00g of tetrabutylammonium bromide, 80g of the polyorganosiloxane (E-2) -containing solution, and 239g of methyl isobutyl ketone, and stirred at 110 ℃ for 4 hours. After cooling to room temperature, the liquid separation washing operation was repeated 10 times with distilled water. Thereafter, the organic layer was recovered, and concentration and dilution with NMP were repeated 2 times by a rotary evaporator to obtain a 15 mass% NMP solution of the polymer (P-13) intermediate. After 0.45g (0.1 mol equivalent) of trimellitic anhydride was added to 50g of the intermediate solution, the solution was prepared using NMP so that the solid content concentration became 10 mass%, and then stirred at room temperature for 4 hours to obtain a NMP solution of the polymer (P-13).

[ example 14A ]

Polymer (P-14) was synthesized according to the following scheme 3.

[ solution 19]

A500 ml three-necked flask was charged with 26.69g (0.3 mol equivalent) of the side chain precursor (ca-1), 3.09g (0.1 mol equivalent) of m-aminobenzoic acid, 2.00g of tetrabutylammonium bromide, 80g of a solution containing polyorganosiloxane (E-1), and 239g of methyl isobutyl ketone, and stirred at 110 ℃ for 4 hours. After cooling to room temperature, the liquid separation washing operation was repeated 10 times with distilled water. Thereafter, the organic layer was collected, and concentration and dilution with NMP were repeated 2 times by a rotary evaporator to obtain a 15 mass% NMP solution of a polyorganosiloxane having an epoxy group and a functional group (referred to as "polymer (R-1)").

Then, 0.13g (0.1 mol equivalent) of magnesium oxide and 0.44g (0.1 mol equivalent) of m-aminobenzoic acid were added to 50g of the solution containing the polymer (R-1), and the mixture was stirred at 80 ℃ for 24 hours. After cooling to room temperature, the mixture was poured into water to dissolve magnesium oxide. Next, extraction was performed using a mixed solution of diethylene glycol diethyl ether and cyclohexane, and the separation and washing operation was repeated 10 times with distilled water. Thereafter, the organic layer was recovered, and concentration and dilution with NMP were repeated 2 times by a rotary evaporator, thereby obtaining a 10 mass% NMP solution of the polymer (P-14).

[ Synthesis example 1]

13.8g (70.0 mmol) of 1,2,3, 4-cyclobutanetetracarboxylic dianhydride as tetracarboxylic dianhydride and 16.3g (76.9 mmol) of 2,2 '-dimethyl-4, 4' -diaminobiphenyl as diamine were dissolved in 170g of NMP and reacted at 25 ℃ for 3 hours, thereby obtaining a solution containing 10 mass% of polyamic acid. Then, the polyamic acid solution was poured into a large excess of methanol to precipitate a reaction product. The precipitate was washed with methanol and dried at 40 ℃ for 15 hours under reduced pressure, thereby obtaining polyamic acid (PAA-1).

[ Synthesis example 2]

In a 200mL two-necked flask, 16.0g (113 mmol) of glycidyl methacrylate and 4.0g (46.5 mmol) of methacrylic acid as polymerization monomers, 0.6g (2.4 mmol) of 2,2' -azobis (2, 4-dimethylvaleronitrile) as a radical polymerization initiator, 1.0g (4.2 mmol) of 2, 4-diphenyl-4-methyl-1-pentene as a chain transfer agent, and 86.4g of NMP as a solvent were charged under nitrogen, and polymerized at 70 ℃ for 5 hours to obtain a target polymer (referred to as "Polymer (PM-1)"). The weight-average molecular weight Mw of the obtained polymer (PM-1) was 20000 and the molecular weight distribution Mw/Mn was 2.1 as measured in terms of polystyrene by GPC.

Comparative Synthesis example 5A

Polymer (PM-2) was synthesized according to scheme 4 below.

[ solution 20]

In a 1000mL eggplant type flask equipped with a stirrer, 10.0g of 3, 4-epoxycyclohexylmethyl methacrylate, 20.1g (1 mol equivalent) of a side chain precursor (ca-1), 500g of cyclopentane and 1.64g (0.1 mol equivalent) of tetrabutylammonium bromide were charged, and the mixture was stirred at 110 ℃ for 4 hours. Thereafter, 300g of cyclohexane and 400g of cyclopentanone were added to the reaction solution, and 5 times of liquid-separation washing were performed with 400g of distilled water. Thereafter, the organic layer was gradually concentrated by a rotary evaporator until the internal volume became 50g, and a white solid precipitated in the process was collected by filtration. By vacuum-drying the white solid, 23.0g of compound (MI-6) was obtained.

Then, 10.0g (16.9 mmol) of the compound (MI-6) as a polymerization monomer, 6.0g (30.5 mmol) of 3, 4-epoxycyclohexylmethyl methacrylate and 4.0g (46.5 mmol) of methacrylic acid, 0.6g (2.4 mmol) of 2,2' -azobis (2, 4-dimethylvaleronitrile) as a radical polymerization initiator, 1.0g (4.2 mmol) of 2, 4-diphenyl-4-methyl-1-pentene as a chain transfer agent and 86.4g of NMP as a solvent were charged in a 200mL two-necked flask under nitrogen and polymerized at 70 ℃ for 5 hours to obtain an objective polymer (referred to as "Polymer (PM-2)"). The weight-average molecular weight Mw of the obtained polymer (PM-2) was 20000 and the molecular weight distribution Mw/Mn was 2.0, as measured in terms of polystyrene by GPC.

< production and evaluation of liquid Crystal display element (1) >)

[ example 1B ]

1. Preparation of liquid Crystal Aligning agent (AL-1)

To 100 parts by mass of the polymer (P-1) obtained in example 1A as the polymer [ P ], NMP and Butyl Cellosolve (BC) were added as solvents to prepare a solution having a solvent composition of NMP/BC =50/50 (mass ratio) and a solid content concentration of 4.0 mass%. The solution was filtered using a filter having a pore size of 1 μm, thereby preparing a liquid crystal aligning agent (AL-1).

2. Manufacture of optical vertical liquid crystal display element

The prepared liquid crystal aligning agent (AL-1) was coated on a transparent electrode surface of a transparent electrode-equipped glass substrate including an ITO film using a spinner, and pre-baked on a hot plate at 80 ℃ for 1 minute. Thereafter, the resultant was heated at 230 ℃ for 1 hour in an oven in which the inside of the chamber was replaced with nitrogen gas, thereby forming a coating film having a thickness of 0.1. Mu.m. Then, the surface of the coating film was irradiated with polarized ultraviolet rays 1,000J/m containing a bright line of 313nm from a direction inclined at 40 ℃ from the substrate normal line using an Hg-Xe lamp and a Glan-Taylor prism ² Thus, a liquid crystal alignment film was produced. The same operation was repeated to produce a pair (two sheets) of substrates having liquid crystal alignment films.

An epoxy resin adhesive containing alumina balls having a diameter of 3.5 μm was applied to the outer periphery of the surface having the liquid crystal alignment film of one of the substrates by screen printing, then the liquid crystal alignment films of the pair of substrates were opposed to each other, pressure-bonded so that the projection directions of the optical axes of ultraviolet rays of the respective substrates on the substrate surfaces became antiparallel, and the adhesive was heat-cured at 150 ℃ for 1 hour. Then, a gap between the substrates is filled with negative type liquid crystal (MLC-6608, manufactured by Merck) from the liquid crystal injection port, and then the liquid crystal injection port is sealed with an epoxy adhesive. Further, in order to remove the flow alignment at the time of liquid crystal injection, the liquid crystal was heated at 130 ℃ and then gradually cooled to room temperature. Next, polarizing plates were bonded to both outer surfaces of the substrate so that the polarization directions thereof were orthogonal to each other and that the angle of 45 ° was formed with respect to the projection direction of the optical axis of the ultraviolet ray of the liquid crystal alignment film on the substrate surface, thereby producing a liquid crystal display element.

3. Evaluation of liquid Crystal alignment Properties

In the liquid crystal display element manufactured as described above, the presence or absence of an abnormal domain (domain) in a bright-dark change when a voltage of 5V is turned ON/OFF (ON/OFF) (applied/released) was observed by an optical microscope, the case where no abnormal domain was present was denoted by "a", the case where an abnormal domain was partially present was denoted by "B", and the case where an abnormal domain was present as a whole was denoted by "C", and the liquid crystal alignment was evaluated. As a result, the liquid crystal alignment property was "a" in the above examples.

4. Evaluation of solvent resistance of liquid Crystal alignment film

After a liquid crystal alignment agent (AL-1) was applied to a silicone substrate using a spinner, the substrate was prebaked at 90 ℃ for 2 minutes on a hot plate to form a coating film having a thickness of 1.0. Mu.m. The resulting coating film was heated on a hot plate at 230 ℃ for 30 minutes. After the resulting membrane was immersed in NMP for 1 minute, it was dried at 100 ℃ for 5 minutes. The rate of change Δ Dnmp of the film thickness before and after immersion was determined by the following equation (1), and solvent resistance was evaluated by the rate of change Δ Dnmp.

Δ Dnmp = [ ((film thickness before immersion) - (film thickness after immersion))/(film thickness before immersion) ] × 100

···(1)

The evaluation was performed by assuming "a" when the rate of change Δ Dnmp was-2% or more and 2% or less, "B" when the rate of change Δ Dnmp was within a range of-5% or more and less than-2% or within a range of more than 2% and 5% or less, and "C" when the rate of change Δ Dnmp was more than 5% or less than-5%. The examples were evaluated for solvent resistance "A".

5. Evaluation of Voltage Holding Ratio (VHR)

In the liquid crystal display device manufactured as described above, after a voltage of 5V was applied at intervals of 167 msec with an application time of 60 μ sec, the voltage holding ratio was measured from the start of application release to after 167 msec. The measurement apparatus used VHR-1 manufactured by Toyo technology (Strand). In this case, the voltage holding ratio is "a" when the voltage holding ratio is 90% or more, "B" when the voltage holding ratio is 80% or more and less than 90%, C "when the voltage holding ratio is 50% or more and less than 80%, and D" when the voltage holding ratio is less than 50%. As a result, the voltage holding ratio was evaluated as "B" in the above examples.

6. Evaluation of thermal reliability

The liquid crystal display element thus manufactured was heated in an oven set at 110 ℃ for 500 hours. The voltage holding ratio before and after heating was measured by the above-described method, and the decrease in the voltage holding ratio after heating was evaluated. In this case, the case where the voltage holding ratio is reduced to 20% or less is referred to as "a", the case where the voltage holding ratio is 20% or more and less than 40% is referred to as "B", and the case where the voltage holding ratio is 40% or more is referred to as "C". As a result, the thermal reliability in the examples was evaluated as "A".

7. Evaluation of printability

The prepared liquid crystal alignment agent (AL-1) was applied to the transparent electrode surface of a glass substrate with a transparent electrode including an ITO film using a flat liquid crystal alignment film printer (manufactured by japan portrait printing (ply), heated on a hot plate at 80 ℃ for 1 minute to remove the solvent, and then heated on a hot plate at 200 ℃ for 10 minutes to form an average film thickness measured by a stylus film thickness meter (manufactured by kola-Tencor) (ply)) as

Coating the film of (2).

The coating film was observed with an optical microscope at a magnification of 20 times, and the presence or absence of uneven printing and pinholes was checked. In the evaluation, a case where all of the printing unevenness and the pinholes were not observed was defined as "a", a case where at least one of a part of the printing unevenness and the pinholes was observed was defined as "B", and a case where at least one of the printing unevenness and the pinholes was observed as a whole was defined as "C". As a result, the printability was evaluated as "B" in the above examples.

Example 2B to example 15B, and comparative example 1B to comparative example 4B and comparative example 7B

Liquid crystal aligning agents were obtained in the same solid content concentrations as in example 1B, except that the formulation compositions were changed as shown in table 2 below. Further, an optical homeotropic liquid crystal display element was produced in the same manner as in example 1B using each liquid crystal aligning agent, and various evaluations were performed using the obtained liquid crystal display element. The results are shown in table 2 below. In table 2, with respect to the numerical values of the compound [ a ], the other polymers, and the additive, the use ratio [ parts by mass ] of each compound to 100 parts by mass of the total of the polymer components used for the preparation of the liquid crystal aligning agent is shown in example 1B, example 8B, comparative example 1B, and comparative example 2B, the use ratio [ parts by mass ] of each compound to 100 parts by mass of the total of the polyamide acid (PAA-1) used for the preparation of the liquid crystal aligning agent is shown in example 2B to example 7B, example 9B, example 10B, example 11B to example 18B, and comparative example 3B to comparative example 7B, and the use ratio [ parts by mass ] of each compound to 100 parts by mass of the total of the polymer (PM-1) used for the preparation of the liquid crystal aligning agent is shown in example 11B.

< production and evaluation of liquid Crystal display element (2) >

[ example 16B ]

1. Preparation of liquid Crystal Aligning agent (AL-16)

To 10 parts by mass of the polymer (P-8) obtained in the above-mentioned example 8A as the polymer [ P ], 100 parts by mass of the polyamic acid (PAA-1) obtained in the above-mentioned synthesis example 1 as another polymer and 3-methoxy-1-butanol (MB), NMP and Butyl Cellosolve (BC) as solvents were added to prepare a solution having a solvent composition of MB/NMP/BC =30/20/50 (mass ratio) and a solid content concentration of 4.0 mass%. The solution was filtered using a filter having a pore size of 1 μm, thereby preparing a liquid crystal aligning agent (AL-16).

2. Manufacturing method of optical horizontal type liquid crystal display element

The prepared liquid crystal aligning agent (AL-16) was applied to the transparent electrode surface of a glass substrate with a transparent electrode including an ITO film using a spinner, and pre-baked on a hot plate at 80 ℃ for 1 minute. Thereafter, the resultant was heated at 230 ℃ for 1 hour in an oven in which the inside of the oven was purged with nitrogen gas, thereby forming a coating film having a thickness of 0.1 μm. Then, the surface of the coating film was irradiated with polarized ultraviolet rays 1,000J/m containing a bright line of 313nm from a direction inclined at 90 ℃ from the substrate normal line using an Hg-Xe lamp and a Glan-Taylor prism ² Thus, a liquid crystal alignment film was produced. The same operation was repeated to produce a pair (two sheets) of substrates having liquid crystal alignment films.

An epoxy resin adhesive containing alumina balls having a diameter of 3.5 μm was applied to the outer periphery of the surface having the liquid crystal alignment film of one of the substrates by screen printing, the liquid crystal alignment films of the pair of substrates were opposed to each other, pressure-bonded so that the projection direction of the optical axis of ultraviolet light of each substrate on the substrate surface became horizontal, and the adhesive was heat-cured at 150 ℃ for 1 hour. Then, a gap between the substrates was filled with positive liquid crystal (MLC-7028-100, manufactured by Merck), and then the liquid crystal injection port was sealed with an epoxy adhesive. Further, in order to remove the flow alignment at the time of liquid crystal injection, the liquid crystal was heated at 130 ℃ and then gradually cooled to room temperature. Next, polarizing plates were bonded to both outer surfaces of the substrate so that their polarization directions were orthogonal to each other and that an angle of 90 ° was formed with respect to the projection direction of the optical axis of the ultraviolet ray of the liquid crystal alignment film on the substrate surface, thereby producing a liquid crystal display element.

3. Evaluation of

The produced horizontal type liquid crystal display device was evaluated for liquid crystal alignment properties, solvent resistance, voltage Holding Ratio (VHR), thermal reliability, and printability in the same manner as in example 1B. The results are shown in table 2 below.

Comparative example 5B

Liquid crystal aligning agents were obtained by preparing the liquid crystal composition at the same solid content concentration as in example 16B, except that the formulation composition was changed as shown in table 2 below. Further, a horizontal type liquid crystal display element was produced in the same manner as in example 16B using each liquid crystal aligning agent, and various evaluations were performed in the same manner as in example 1B using the obtained liquid crystal display element. The results are shown in table 2 below.

< production and evaluation of liquid Crystal display element (3) >)

[ example 17B ]

1. Preparation of liquid Crystal Aligning agent (AL-17)

A liquid crystal aligning agent (AL-17) was prepared at the same solid content concentration as in example 16B, except that the formulation composition was changed as shown in table 2 below.

Production of PSA type liquid Crystal display element

The prepared liquid crystal aligning agent (AL-17) was applied to the transparent electrode surface of a glass substrate with a transparent electrode including an ITO film using a spinner, and pre-baked on a hot plate at 80 ℃ for 1 minute. Thereafter, the resultant was heated at 230 ℃ for 1 hour in an oven in which the inside of the chamber was replaced with nitrogen gas, thereby forming a coating film having a thickness of 0.1. Mu.m. The same operation was repeated to produce a pair (two sheets) of substrates having liquid crystal alignment films.

An epoxy resin adhesive containing alumina balls having a diameter of 3.5 μm was applied to the outer periphery of the surface having the liquid crystal alignment film of one of the substrates by screen printing, and then the liquid crystal alignment films of the pair of substrates were opposed to each other, and the adhesive was thermally cured at 150 ℃ for 1 hour. Then, a gap between the substrates is filled with negative type liquid crystal (MLC-6608, manufactured by Merck) from the liquid crystal injection port, and then the liquid crystal injection port is sealed with an epoxy adhesive. Further, in order to remove the flow alignment at the time of liquid crystal injection, the liquid crystal was heated at 130 ℃ and then gradually cooled to room temperature.

Next, an alternating current of 10V was applied between a pair of electrodes at a frequency of 60Hz, and an ultraviolet irradiation apparatus using a metal halide lamp as a light source was used in a state of driving the liquid crystal at a rate of 100,000J/m ² The irradiation amount of (3) is irradiated with ultraviolet rays. Furthermore, the irradiation amount is such thatA value measured with a light meter measuring with a 365nm wavelength reference. Then, polarizing plates were bonded to both outer surfaces of the substrate so that the polarizing directions thereof were orthogonal to each other and that the angle of 45 ° was formed with respect to the projection direction of the optical axis of the ultraviolet ray of the liquid crystal alignment film on the substrate surface, thereby producing a liquid crystal display element.

3. Evaluation of

The PSA liquid crystal display device thus manufactured was evaluated for liquid crystal alignment properties, solvent resistance, voltage Holding Ratio (VHR), thermal reliability, and printability in the same manner as in example 1B. The results are shown in table 2 below.

Example 18B and comparative example 6B

Liquid crystal aligning agents were obtained in the same solid content concentrations as in example 16B, except that the formulation compositions were changed as shown in table 2 below. Further, a liquid crystal display element was produced using each liquid crystal aligning agent in the same manner as in example 17B, and various evaluations were performed using the obtained liquid crystal display element in the same manner as in example 1B. The results are shown in table 2 below.

[ Table 2]

In table 2, the numerical value of the solvent indicates the blending ratio (parts by mass) of each solvent with respect to 100 parts by mass of the total amount of solvents used for preparing the liquid crystal aligning agent. The abbreviation of the solvent is as follows.

NMP: n-methyl-2-pyrrolidone

BC: butyl cellosolve

MB: 3-methoxy-1-butanol

CPN: cyclopentanone

PGME: propylene glycol monomethyl ether

EDM: diethylene glycol methyl ethyl ether

PGMEA: propylene glycol monomethyl ether acetate

From the results of the above examples, it is understood that liquid crystal display elements having excellent reliability against heat can be obtained according to examples 1B to 18B using the liquid crystal aligning agent containing the silicon-containing compound [ a ]. In addition, the obtained liquid crystal display device is excellent in the liquid crystal alignment property and the voltage holding ratio in addition to the thermal reliability, and the liquid crystal alignment film is also excellent in the solvent resistance and the printability. On the other hand, comparative examples 1B to 7B using the liquid crystal aligning agent not containing the silicon-containing compound [ A ] are inferior in thermal reliability to examples. Further, not only the thermal reliability but also the solvent resistance, the voltage holding ratio and the printability were observed in combination, and the balance of the examples was improved well.

The present disclosure is described in terms of embodiments, and it is to be understood that the present disclosure is not limited to the embodiments or configurations. The present disclosure also includes various modifications and equivalent variations. In addition, various combinations or modes, and further, other combinations or modes including only one element, one or more, or one or less of these elements are also included in the scope or the idea of the present disclosure.

Claims

1. A liquid crystal aligning agent contains a silicon-containing compound having a cyclic ether group and a functional group B which is reactive with the cyclic ether group, the functional group B being a carboxyl group.

2. The liquid crystal aligning agent according to claim 1, wherein the silicon-containing compound is a polymer [ P ] having a siloxane skeleton.

3. The liquid crystal aligning agent according to claim 2, wherein the polymer [ P ] has a photo-aligning group.

4. The liquid crystal aligning agent according to claim 2 or 3, wherein the polymer [ P ] has an alignment-developing site for aligning liquid crystal molecules.

5. The liquid crystal aligning agent according to claim 2 or 3, wherein the polymer [ P ] has a group containing a carbon-carbon unsaturated bond.

6. The liquid crystal aligning agent according to claim 2 or 3, further comprising a polymer [ Q ] different from the polymer [ P ].

7. The liquid crystal aligning agent according to claim 6, wherein the polymer [ Q ] is at least one selected from the group consisting of polyamic acids, polyamic acid esters, polyimides, and polymers of monomers having polymerizable unsaturated bonds.

8. A liquid crystal alignment film formed from the liquid crystal aligning agent according to any one of claims 1 to 7.

9. A liquid crystal cell comprising the liquid crystal alignment film according to claim 8.

10. A polyorganosiloxane having a cyclic ether group and a functional group B which is reactive with the cyclic ether group, the functional group B being a carboxyl group.