TWI785018B - Liquid crystal alignment agent, liquid crystal alignment film, liquid crystal element and polyorganosiloxane - Google Patents

Abstract

The liquid crystal alignment agent contains a silicon-containing compound having a cyclic ether group and a functional group B reactive with the cyclic ether group. An example of the functional group B that the silicon-containing compound has is a functional group that reacts with a cyclic ether group by heat. An example of a silicon-containing compound is a polymer [P] having a siloxane skeleton.

Description

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

The disclosure relates to a liquid crystal alignment agent, a liquid crystal alignment film, a liquid crystal element and polyorganosiloxane.

[Cross-reference of related applications]

This application is based on Japanese application number 2017-43288 filed on March 7, 2017, and the content of the description is cited in this application.

As a liquid crystal element, a nematic liquid crystal having a positive dielectric anisotropy represented by a twisted nematic (Twisted Nematic, TN) type, a super twisted nematic (Super Twisted Nematic, STN) type, etc. is known. A liquid crystal element, or a vertical alignment (Vertical Alignment, VA) type liquid crystal element using a homeotropic alignment mode of a nematic liquid crystal having negative dielectric anisotropy, and in-plane switching (In-Plane Switching, IPS) Type, fringe field switching (Fringe Field Switching, FFS) type, etc., using an electric field parallel to the substrate to switch the parallel (homogeneous) aligned liquid crystal and other liquid crystal elements.

These liquid crystal elements include a liquid crystal alignment film having a function of aligning liquid crystal molecules in a certain direction. As the material used in the production of the liquid crystal alignment film, Known polyamic acid, polyimide, polyamide, polyester, polyorganosiloxane, etc., especially polyamic acid and polyimide due to heat resistance, mechanical strength, and affinity with liquid crystal molecules Since they are excellent, they have been used preferably since ancient times (for example, refer to Patent Document 1 to Patent Document 3). When manufacturing a liquid crystal element, a liquid crystal alignment film is formed using a liquid crystal alignment agent obtained by dissolving these polymer components in an organic solvent.

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

With regard to LCD components, the previous main markets were TV sets, mobile phones. Tablet PCs, etc., but have been widely used as display devices in recent years. For liquid crystal elements, for example, a wide range of new applications have been found for vehicle-mounted devices, digital signage, and industrial use, and they are used in various situations.

[Prior art literature] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open No. 4-153622

[Patent Document 2] Japanese Patent Laid-Open No. 56-91277

[Patent Document 3] Japanese Patent Laid-Open No. 11-258605

[Patent Document 4] Japanese Patent Laid-Open No. 9-281502

With regard to the novel market of liquid crystal components, it is sometimes required to Durability requires higher reliability than previous technologies. For example, when it is assumed to be used at a high temperature in summer or in a tropical region, long-term heat resistance (thermal reliability) is required. On the other hand, for the display quality of the liquid crystal display panel, the liquid crystal alignment film in direct contact with the liquid crystal layer has a large contribution rate. Therefore, as a liquid crystal alignment film, even when the liquid crystal display panel is exposed to high temperature conditions, it is required that the voltage retention rate and driving characteristics are not easily changed, and the display quality is not easily deteriorated.

This disclosure is made in view of the above circumstances, and one of the objects is to provide a liquid crystal element excellent in thermal reliability.

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

<1> A liquid crystal alignment agent containing 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 alignment agent as described in <1>.

<3> A liquid crystal element comprising the liquid crystal alignment film as described in said <2>.

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

According to the liquid crystal alignment agent of this disclosure, the liquid crystal element excellent in the reliability to heat can be obtained.

<<Liquid crystal alignment agent>>

The liquid crystal alignment agent disclosed herein contains a silicon-containing compound (hereinafter also referred to as "silicon-containing compound [A]") having a cyclic ether group and a functional group reactive with the cyclic ether group. The silicon-containing compound [A] has a silicon-containing structure with high thermal stability and a self-crosslinking group. Hereinafter, each component contained in the liquid crystal alignment agent of this disclosure, and other components arbitrarily blended as needed are demonstrated.

<Silicon-containing compound [A]>

The cyclic ether group contained in the silicon-containing compound [A] is preferably an oxetanyl group or an oxiranyl group, more preferably an oxiranyl group, in terms of high reactivity due to heat. . In terms of self-crosslinking by heating during post-baking and better storage stability of the liquid crystal alignment agent, 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 a cyclic ether group by heat. Specific examples of the functional group B include carboxyl, isocyanate, hydroxyl, amine, and alkoxymethyl, groups in which carboxyl, isocyanate, hydroxyl, or amine are protected with protecting groups, and the like. In terms of better storage stability and higher reactivity with cyclic ether groups by heating, the functional group B is preferably a carboxyl group or a protected carboxyl group (hereinafter also referred to as "protected carboxyl group") .

The protected carboxyl group is preferably detached 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.

(In formula (1), R ¹¹ , R ¹² and R ¹³ are each independently an alkyl group with 1 to 10 carbons or a monovalent alicyclic hydrocarbon group with 3 to 20 carbons, or R ¹¹ and R ¹² are bonded to each other And together with the carbon atoms bonded by R ¹¹ and R ¹² , a divalent alicyclic hydrocarbon group or cyclic ether group with 4 to 20 carbons is formed, and R ¹³ is an alkyl group with 1 to 10 carbons, and an alkyl group with 2 to 2 carbons Alkenyl group with 10 or aryl group with carbon number 6~20. "*" indicates bond)

Examples of the silicon-containing compound [A] include low-molecular-weight silane compounds, polyorganosiloxanes, and the like. 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, etc. are mentioned. In terms of obtaining a liquid crystal element with higher thermal reliability improvement effect, higher solvent resistance of the obtained liquid crystal alignment film, and better liquid crystal alignment and voltage retention, the silicon-containing compound [A] Preferably, it is 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]").

<polymer[P]>

The synthesis method of the polymer [P] is not particularly limited, but the following methods 1 to 3 are exemplified as preferable synthesis methods.

． Method 1: by treating the hydrolyzable silane compound (S1) alone or the mixture of the silane compound (S1) and other hydrolyzable silane compounds having a cyclic ether group Polyorganosiloxane (hereinafter, also referred to as "polyorganosiloxane E") having a cyclic ether group in the side chain is synthesized by hydrolytic condensation, and then polyorganosiloxane E is combined with a carboxyl group having an amino group Acid (hereinafter, also referred to as "amino group-containing carboxylic acid") reaction to obtain polyorganosiloxane having amino groups in the side chain, and further, the obtained amino group-containing polyorganosiloxane and carboxylic anhydride method of response.

． Method 2: by hydrolytic condensation of 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 other hydrolyzable silane compounds Synthesizing polyorganosiloxane having amine groups and cyclic ether groups in the side chain (hereinafter also referred to as "polyorganosiloxane M"), and then reacting the obtained polyorganosiloxane M with carboxylic anhydride method.

． Method 3: Polyorganosiloxane E is synthesized by hydrolytic condensation of silane compound (S1) alone or a mixture of silane compound (S1) and other hydrolyzable silane compounds, and then polyorganosiloxane E is mixed with Amino carboxylic acid reaction method.

Among these, it is preferable to use method 1 at the point that it is simple and can obtain a polymer having high solubility in a solvent and high heat resistance.

As the silane compound (S1), a hydrolyzable silane compound having an oxetanyl group or an oxiranyl group can be preferably used. Specific examples thereof include: glycidyloxymethyltrimethoxysilane, glycidyloxymethyltriethoxysilane, 2-glycidyloxyethyltrimethoxysilane, 2-glycidyloxy 3-Glycidoxypropyltriethoxysilane, 3-Glycidoxypropyltrimethoxysilane, 3-Glycidoxypropyltriethoxysilane, 3-Glycidoxypropylmethyldimethoxy Silane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, (meth)acrylic acid (3-ethyloxetane (alk-3-yl)methyl, (meth)acrylic acid (3-methyloxetan-3-yl)methyl, and the like. In addition, silane compound (S1) may be used individually by 1 type, and may use it in combination of 2 or more types.

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-aminopropyltrimethoxysilane, Ethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxy Silane, N-phenyl-3-aminopropyltrimethoxysilane, etc. In addition, silane compound (S2) may be used individually by 1 type, and may use it in combination of 2 or more types.

Other silane compounds are silane compounds other than silane compound (S1) and silane compound (S2), and are not particularly limited, for example, tetraalkoxysilane compounds such as tetramethoxysilane and tetraethoxysilane; methyl Alkoxysilane compounds containing alkyl or aryl groups such as triethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, dimethyldiethoxysilane, etc.; 3-mercaptopropyltriethyl Sulfur-containing alkoxysilane compounds such as oxysilane and mercaptomethyltriethoxysilane; 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropyl Alkoxysilane compounds containing unsaturated bonds such as methyldimethoxysilane, 3-(meth)acryloxypropylmethyldiethoxysilane, and vinyltriethoxysilane; trimethoxysilane Alkoxysilane compounds containing acid anhydride groups such as silyl propyl succinic anhydride; N-ethoxycarbonyl-3-aminopropyl trimethoxysilane, 3-ureidopropyl trimethoxysilane, 3- Nitrogen-containing alkoxysilane compounds such as ureidopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylene)propylamine, etc. as other silane compounds One of these may be used alone, or two or more of them may be used in combination.

Examples of amino group-containing carboxylic acids include: 3-aminobenzoic acid, 4-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, etc. Regarding the amino group-containing carboxylic acid, one of these may be used alone, or two or more of them may be used in combination.

The carboxylic acid anhydride is not particularly limited as long as it has one acid anhydride group. Examples of carboxylic anhydrides include trimellitic anhydride, 4-nitrophthalic anhydride, 3-nitrophthalic anhydride, 4-ethynylphthalic anhydride, 4-(1-propyne base) phthalic anhydride, 4-phenylethynyl phthalic anhydride, 4-methylphthalic anhydride, phthalic anhydride, maleic anhydride, succinic anhydride, itaconic anhydride, allyl Succinic anhydride, 1,2-cyclohexanedicarboxylic anhydride, 1-cyclohexene-1,2-dicarboxylic anhydride, cis-4-cyclohexene-1,2-dicarboxylic anhydride, 5-nor Bornene-2,3-dicarboxylic anhydride, Homophthalic acid anhydride, glutaric anhydride, 3-trimethoxysilylpropyl succinic anhydride, cyclohexane-1,2,4-tricarboxylic anhydride Acid-1,2-anhydride, etc. As for the carboxylic anhydride, one of these may be used alone, or two or more of them may be used in combination.

(hydrolysis condensation reaction)

In methods 1 to 3, the hydrolytic condensation reaction using a hydrolyzable silane compound is carried out by reacting one or more kinds of hydrolyzable silane compounds with water, preferably in the presence of a suitable catalyst and an organic solvent. And proceed. In Method 1 and Method 3, the ratio of the silane compound (S1) to the total amount of monomers used in the synthesis of polyorganosiloxane is preferably 5 mol% or more, more preferably 10 mol% or less superior.

In addition, in Method 2, the usage ratio of the silane compound (S1) is preferably 5 mol % to 99 mol %, more preferably Set as 10 mol%~95 mol%. The usage ratio of the silane compound (S2) is preferably 0.5 mol % to 50 mol %, more preferably 1 mol %, based on the total amount of monomers used in the synthesis of polyorganosiloxane ~40 mole %.

During the hydrolysis and condensation reaction, the proportion of water used is preferably 1 mol to 30 mol relative to 1 mol of the silane compound (total amount) used in the reaction. As a catalyst to be used, an acid, an alkali metal compound, an organic base, a titanium compound, a zirconium compound etc. are mentioned, for example. Among them, tertiary organic amines or quaternary organic amines are preferred, for example, triethylamine, tri-n-propylamine, tri-n-butylamine, pyridine, 4-dimethylaminopyridine, etc. Tertiary organic amines; quaternary organic amines such as tetramethylammonium hydroxide. The usage amount of the catalyst should be appropriately set according to the type of the catalyst, reaction conditions such as temperature, etc., for example, it is preferably 0.01 times mole to 3 times mole relative to the total amount of the silane compound.

Examples of the organic solvent used in the hydrolysis condensation reaction include hydrocarbons, ketones, esters, ethers, alcohols and the like. As specific examples of these, hydrocarbons include toluene, xylene, etc., and ketones include methyl ethyl ketone, methyl isobutyl ketone, methyl-n-amyl ketone, diethyl ketone, and cyclohexanone. etc.; esters include ethyl acetate, butyl acetate, isoamyl acetate, propylene glycol monomethyl ether acetate, 3-methoxybutyl acetate, ethyl lactate, etc.; ethers include ethylene glycol Dimethyl ether, ethylene glycol diethyl ether, tetrahydrofuran, etc.; alcohols such as 1-hexanol, 4-methyl-2-pentanol, ethylene glycol monomethyl ether, ethylene glycol Alcohol monoethyl ether, etc. Among these, it is preferable to use a water-insoluble or poorly water-soluble organic solvent. The usage ratio of the organic solvent is preferably 10 to 10,000 parts by mass relative to 100 parts by mass in total of the silane compounds used in the reaction.

The said hydrolysis condensation reaction is preferably implemented by heating with an oil bath etc., for example. At this time, the heating temperature is preferably set to 130° C. or lower, and the heating time is preferably set to 0.5 hours to 12 hours. After completion of the reaction, if necessary, the organic solvent layer fractionated from the reaction solution is dried with a desiccant, and then the solvent is removed to obtain the target polyorganosiloxane. In addition, the synthesis method of polyorganosiloxane is not limited to the said hydrolysis-condensation reaction, For example, the method of making a hydrolyzable silane compound react in the presence of oxalic acid and alcohol, etc. can also be performed.

(Reaction of Polyorganosiloxane E with Amino-Containing Carboxylic Acid (1))

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

As a catalyst used for the reaction, for example, a curing accelerator can be used in addition to an organic base, which is preferably used. As specific examples of these, organic bases include primary organic amines, secondary organic amines, tertiary organic amines, and quaternary organic amine salts; hardening accelerators include tertiary amines, imidazole derivatives, and organic phosphorus compounds. , Quaternary phosphonium salts, diazabicycloolefins, organometallic compounds, quaternary ammonium halides, metal halides, latent hardening accelerators, etc. Examples of latent hardening accelerators include: high-melting point dispersion type latent hardening accelerators (such as amine addition type accelerators, etc.), microcapsule type latent hardening accelerators, amine salt type latent hardening accelerators, pyrolysis Release type thermal cationic polymerization type latent hardening accelerator, etc. As the catalyst, among these, quaternary organic amine salts or quaternary ammonium halides are preferably used.

As specific examples of the catalyst, quaternary organic amine salts include tetramethylammonium hydroxide, etc.; quaternary ammonium halides include tetraethylammonium bromide, tetra-n-butylammonium bromide, chloride Tetraethylammonium, tetra-n-butylammonium chloride, etc. As a catalyst, one or more types 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 between polyorganosiloxane E and carboxylic acid include ketones, ethers, esters, amides, alcohols, and the like. As a specific example of the organic solvent, the ketone can include, for example, methyl ethyl ketone, methyl isobutyl ketone, methyl-n-amyl ketone, diethyl ketone, cyclohexanone, etc.; the ether such as Ethylene glycol dimethyl ether, ethylene glycol diethyl ether, tetrahydrofuran, dioxane, etc. can be mentioned; Examples of the ester include ethyl acetate, n-butyl acetate, isoamyl acetate, propylene glycol monomethyl ether acetate, 3-methoxybutyl acetate, ethyl lactate, etc.; said amides, for example, include formamide, N-methylformamide, N,N-dimethylformamide, N-ethyl Formamide, N,N-Diethylformamide, Acetamide, N-Methylacetamide, N,N-Dimethylacetamide, N-Ethylacetamide, N,N- Diethylacetamide, N-methylacrylamide, N-methylpyrrolidone, N-formylmorpholine, N-formylpiperidine, N-formylpyrrolidine, N-ethyl Acyl morpholine, N-acetylpiperidine, N-acetylpyrrolidine, etc.; the alcohol can be, for example, 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 Ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, etc., one or more selected from these can be used.

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

The proportion of the amino group-containing carboxylic acid used is appropriately set according to the number of functional groups B introduced into the side chain of polyorganosiloxane E, but the thermal reliability of the liquid crystal device brought about by the introduction of functional groups B can be sufficiently obtained. From the viewpoint of improving the solvent resistance of the polyorganosiloxane and the solvent resistance of the liquid crystal alignment film, it is preferably set at 0.005 mol to 0.5 mol with respect to 1 mol of the silane compound (total amount) used in the synthesis of polyorganosiloxane Ear. The lower limit of the usage ratio is more preferably at least 0.01 mol, and still more preferably at least 0.05 mol. In addition, the upper limit is more preferably at most 0.4 mol, and still more preferably at most 0.3 mol.

In Method 1, when polyorganosiloxane E is reacted with an amino group-containing carboxylic acid, a functional group that imparts a desired function to the polymer (hereinafter also referred to as "functional group") is introduced into polyorganosiloxane E. For the purpose of "reactive group"), a carboxylic acid having a functional group (hereinafter also referred to as "functional group-containing carboxylic acid") may be used in combination. In the case of using a functional group-containing carboxylic acid together with an amino group-containing carboxylic acid, in order to introduce a sufficient amount of the functional group without inhibiting the introduction of the amino group, it is preferable to use the functional group-containing carboxylic acid The total usage ratio is 0.05 to 0.8 mol, more preferably 0.1 to 0.7 mol with respect to 1 mol of the silane compound (total amount) used for the synthesis of the polyorganosiloxane.

The reaction between polyorganosiloxane E and amino-containing carboxylic acid is carried out at a temperature of preferably 0°C to 200°C, more preferably 50°C to 150°C, preferably 0.1 hour to 50 hours, more preferably 0.5 hours ~ 20 hours. After the reaction, if necessary, the organic solvent layer separated from the reaction solution is dried with a desiccant, and then the solvent is removed to obtain an amino group-containing polyorganosiloxane.

(reaction of polyorganosiloxane with amine group and carboxylic acid anhydride)

In method 1 and method 2, the amino group which polyorganosiloxane has, and the acid anhydride group which carboxylic anhydride has are made to react. Thereby, the polyorganosiloxane which has an epoxy group and a carboxyl group in a side chain can be obtained as a polymer [P].

From the point of view 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 brought about by the introduction of the functional group B (here, a carboxyl group) toward the polyorganosiloxane side chain, The usage ratio of the carboxylic anhydride is preferably 0.1 mol to 2.0 mol with respect to 1 mol of amino groups (total amount) that the polyorganosiloxane has. The lower limit of the usage ratio is more preferably 0.2 mol or more, still more preferably 0.3 mol or more. In addition, the upper limit is more preferably at most 1.5 mol, and still more preferably at most 1.2 mol.

The reaction is preferably carried out in an appropriate organic solvent. Examples of the organic solvent used include aprotic polar solvents, phenolic solvents, alcohols, ketones, esters, ethers, halogenated hydrocarbons, and hydrocarbons. As a preferable organic solvent, can enumerate and be selected from N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethylsulfoxide, One or more species selected from the group consisting of γ-butyrolactone, tetramethylurea, hexamethylphosphoryltriamine, m-cresol, xylenol and halogenated phenol.

In the above reaction, the reaction temperature is preferably -20°C to 100°C, more preferably 0°C to 80°C. The reaction time is preferably 1 hour to 48 hours, more preferably 2 hours to 12 hours. The obtained reaction solution may be directly used for the preparation of a liquid crystal alignment agent, or may be used for the preparation of a liquid crystal alignment agent after isolating the polymer [P] contained in the reaction solution using a known isolation method.

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

In method 3, the cyclic ketone group which polyorganosiloxane E has, and the amine group which the amine group-containing carboxylic acid has are made to react. Thereby, the polyorganosiloxane which has an epoxy group and a carboxyl group in a side chain can be obtained as a 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 to the side chain of the polyorganosiloxane, the use of the amino group-containing carboxylic acid The ratio is preferably 0.005 mol to 0.5 mol with respect to 1 mol of the silane compound (total amount) used for the synthesis of the polyorganosiloxane. The lower limit of the usage ratio is more preferably at least 0.01 mol, and still more preferably at least 0.05 mol. Moreover, as for an upper limit, it is more preferable that it is 0.4 mol or less, and it is still more preferable that it is 0.3 mol or less.

The reaction is carried out in a suitable solvent in the presence of a suitable catalyst, if necessary. As a catalyst, magnesium oxide, calcium oxide, potassium carbonate, etc. are mentioned, for example. The solvent is preferably one that can uniformly dissolve or decompose the amino group-containing polyorganosiloxane and carboxylic anhydride, and examples thereof include N-methyl-2-pyrrolidone, tetrahydrofuran, and the like. In the above reaction, the reaction temperature is preferably -20°C~180°C, more preferably 10°C~120°C. The reaction time is preferably 1 hour to 72 hours, more preferably 2 hours to 48 hours. earned The reaction solution can be used for preparation of a liquid crystal alignment agent after isolating the polymer [P] contained in the reaction solution using a known isolation method.

In method 2 and method 3, in the case of obtaining a polyorganosiloxane having a functional group as the polymer [P], in method 2, before reacting a polyorganosiloxane having an amino group with a carboxylic anhydride Reaction of a polyorganosiloxane having a cyclic ether group with a carboxylic acid containing a functional group. Regarding method 3, the polyorganosiloxane having a cyclic ether group can be reacted before reacting the polyorganosiloxane with an amino group-containing carboxylic acid. Polyorganosiloxanes are reacted with carboxylic acids containing functional groups. Regarding the reaction conditions of the polyorganosiloxane having a cyclic ether group and the functional group-containing carboxylic acid, the description of Method 1 is applied.

An example of Method 1 to Method 3 is shown in Flow A1, Flow A2, Flow B, and Flow C below. In method 1, when using epoxy group-containing silane compound as silane compound (S1), using 3-aminobenzoic acid as amino group-containing carboxylic acid, and using trimellitic anhydride as carboxylic anhydride, it can be obtained by Polymer [P] was obtained by the following process A1 (beta cleavage of epoxy group) and process A2 (α cleavage of epoxy group).

(In process A1 and process A2, L ¹ is a divalent linking group, R ¹ is a hydrogen atom)

In 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 process B.

(In process B, L ¹ and L ² are independently divalent linking groups)

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

(In scheme C, L ¹ is a divalent linking group, R ³ is a hydrogen atom)

According to the process A1, process A2 and process B, as the polymer [P], a polyorganosiloxane having a cyclic ether group (here, an oxirane group) and a carboxyl group, and a polyorganosiloxane having a cyclic ether group can be obtained. A polyorganosiloxane with amino groups. In addition, according to the scheme C, a polyorganosiloxane having a cyclic ether group and a carboxyl group can be obtained as the polymer [P].

(functional basis)

It is preferable that polymer [P] has a functional group in a side chain according to the driving mode of the applied liquid crystal element. For example, when a liquid crystal alignment agent is used in the manufacture of a vertical alignment type or a horizontal alignment type liquid crystal element, the polymer [P] preferably has a liquid crystal The orientation display site of the crystal molecular alignment is used as a functional group. In addition, when imparting liquid crystal alignment energy to a polymer film formed of a liquid crystal alignment agent by a photo-alignment method, it is preferable that the polymer [P] has a photo-alignment group as a functional group. In addition, in the case of increasing the alignment restriction force of liquid crystal molecules by irradiating light from the outside of the liquid crystal cell after construction of the liquid crystal cell, the polymer [P] preferably has a group containing a carbon-carbon unsaturated bond as functional basis.

[Orientation display site]

The alignment display site is a group that can control the alignment direction of the liquid crystal molecules in the liquid crystal layer in a polymer film formed using a liquid crystal alignment agent. Furthermore, the alignment exhibiting portion can control the alignment of the liquid crystal molecules without light irradiation. As a specific example of an alignment expression part, the group etc. which are represented by following formula (3) are mentioned, for example.

(In the formula (3), R ^I is an alkyl group with 1 to 40 carbons, a fluoroalkyl group with 1 to 40 carbons, and a group formed by substituting at least one hydrogen atom of an alkyl group with 1 to 40 carbons by a cyano group. A valent group, a cyano group, a nitro group or a fluorine atom, or a hydrocarbon group with a carbon number of 17 to 51 with a steroid skeleton. Z ^I is a single bond, *-O-, *-COO- or *-OCO- (wherein, with The bonding bond of "*" is the R ^I side). R ^II is a cyclohexyl or phenylene group, and the hydrogen atom bonded to the ring can also be cyano, nitro, fluorine atom, trifluoromethyl or carbon number 1 ~3 alkyl substitution. n1 is 1 or 2, when n1 is 2, the two R ^II can be the same or different from each other. n2 is 0 or 1. Z ^II is a single bond, *-O-, *-COO -or *-OCO-(wherein, the bonding bond with "*" is on the R ^II side). n3 is an integer of 0~2, and n4 is 0 or 1. Among them, in the case of n2=0 and n4=0 , R ^I is more than 4 carbon number)

Examples of the divalent group represented by "-(R ^II ) _n1 -" in the formula (3) include 1,4-phenylene, 1,4-cyclohexylene, 4,4'-extension Phenyl, 4,4'-bicyclohexyl, following formula

(In the formula, the bond with "*" is bonded with Z ^I )

The groups represented respectively are preferred divalent groups.

[Photoalignment group]

The photoalignment group is a functional group that imparts anisotropy to the film by photoisomerization reaction, photodimerization reaction, photodecomposition reaction, and photofries rearrangement reaction caused by light irradiation. Specific examples of photoalignment groups include azobenzene-containing groups containing azobenzene or derivatives thereof as a basic skeleton, cinnamic acid-containing groups containing cinnamic acid or derivatives thereof (cinnamic acid structure) as a basic skeleton, and A structural group, a chalcone-containing group containing chalcone or a derivative thereof as a basic skeleton, a benzophenone-containing group containing a benzophenone or a derivative thereof as a basic skeleton, a group containing coumarin or its A coumarin-containing group containing a derivative as a basic skeleton, a group containing cyclobutane or a derivative thereof as a basic skeleton Structures containing cyclobutane, etc. Among them, a group having a cinnamic acid structure represented by the following formula (5) is preferable at the point of high sensitivity to light or at the point of being easily introduced into a polymer side chain. Polymer [P] is preferable at the point which can improve the high-speed response of the obtained liquid crystal element by having a pretilt angle expressing part with the structure represented by following formula (5).

(In 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 may be the same or different. "*" represents a bond)

[group containing carbon-carbon unsaturated bond]

As a group containing a carbon-carbon unsaturated bond, the group represented by following formula (4), etc. are mentioned, for example.

(In formula (4), R is a hydrogen atom or a methyl group, X ^I and X ^II are respectively 1,4-phenylene, alkanediyl with 1 to 8 carbons, Z is an oxygen atom, -COO-* or -OCO-* (wherein, the bonding bond with "*" is bonded to X ^II ), a, b, c and d are respectively 0 or 1. Wherein, when c is 0 and d is 1, X ^II is 1,4-phenylene, when b is 0, c is 0)

Specific examples of the group represented by the formula (4) include vinyl, allyl, p-vinylphenyl, (meth)acryloxyalkyl, 4-((methyl) Acryloxy)alkyl)phenyl, ((meth)acryloxy)phenyl)alkyl, 4-((meth)acryloxyalkoxy)phenyl, (meth)acrylic Acyloxyalkoxyalkyl, 6-{[6-(acryloxy)hexyl]oxy}hexyl and the like.

When the polymer [P] is a polymer having a functional group in the side chain, examples of the polymer include (I) a method synthesized by polymerization using a monomer having a functional group, (II) A method of introducing a side chain using a cyclic ether group possessed by the polymer [P] or its precursor, and the like. Among these, (II) is preferable in terms of simple and easy adjustment of the introduction rate of the functional group. Among them, it is preferable to combine a polyorganosiloxane having a cyclic ether group (polyorganosiloxane E in method 1 and method 3, polyorganosiloxane M in method 2), and a polyorganosiloxane having a functional group B and a compound of a functional group (hereinafter, also referred to as "side chain precursor [C]") are reacted and produced.

In addition, the polymer [P] may have only one kind of functional group among an alignment developing site, a photoalignment group, and a group containing a carbon-carbon unsaturated bond, or may have multiple types. When the polymer [P] has multiple functional groups, one functional group and the other functional groups may exist in the same side chain or may exist in different side chains. In addition, all of the functional groups may be contained in a single type of polymer, or a polymer having a part of the desired functional groups and a polymer having the remaining functional groups may be used as a mixture. Of course, three or more polymers may be mixed and used as the polymer [P], or two or more polymers having the same functional group may be mixed and used. polymer. Since any aspect may be used, the polymer [P] should just have each functional group as a single thing or a mixture as a whole.

The polymer [P] preferably has a polystyrene-equivalent weight average molecular weight (Mw) measured by gel permeation chromatography (Gel Permeation Chromatography, GPC) of 1,000 to 300,000, more preferably 2,000 to 100,000. Among them, when the polymer [P] is a modified polymer modified using a compound having a functional group, it is preferable that the weight average molecular weight of the polymer before modification is within the above-mentioned range. The molecular weight distribution (Mw/Mn) represented by the ratio of Mw and the polystyrene-equivalent number average molecular weight (Mn) measured by GPC is preferably 5 or less, more preferably 4 or less. Furthermore, the polymer [P] used in the preparation of the liquid crystal alignment agent may be only one kind, or two or more kinds may be combined.

In terms of the effect of improving the thermal reliability of the obtained liquid crystal element, the content ratio of the polymer [P] in the liquid crystal alignment agent is relatively small relative to 100 parts by mass of all the polymers contained in the liquid crystal alignment agent. Preferably, it is 0.1 mass part or more, More preferably, it is 0.5 mass part or more, More preferably, it is 1 mass part or more. In addition, when preparing other polymers, the content of the polymer [P] is preferably at most 50 parts by mass, more preferably at most 25 parts by mass, relative to 100 parts by mass of other polymers contained in the liquid crystal alignment agent. , and more preferably 20 parts by mass or less.

<other ingredients>

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

(other polymers)

In order to improve various properties such as electrical characteristics, liquid crystal alignment, and reliability, or to achieve cost reduction, the liquid crystal alignment agent disclosed in the present disclosure may contain a polymer different from the polymer [P] (hereinafter, also referred to as as "other polymers"). The main skeleton of other polymers is not particularly limited. Examples of other polymers include polyamic acid, polyimide, polyamic acid ester, polyamide, polyorganosiloxane other than polymer [P], polyester, cellulose derivatives, Polyacetals, polystyrene derivatives, poly(styrene-phenylmaleimide) derivatives, poly(meth)acrylates, and other main-skeleton polymers. In addition, in this specification, "(meth)acrylate" means including acrylate and methacrylate.

From the viewpoint of electrical properties, affinity with liquid crystal, mechanical strength, affinity with polymer [P], etc., it is preferable to use polyamic acid, polyamic acid ester, etc. , polyimide, and at least one polymer of the group consisting of a polymer of a monomer having a polymerizable unsaturated bond (hereinafter also referred to as "polymer [Q]").

With respect to 100 parts by mass of the polymer [P] used in the preparation of the liquid crystal alignment agent, the blending ratio of the polymer [Q] is preferably 100 parts by mass or more, more preferably 100 parts by mass to 2000 parts by mass, Furthermore, it is more preferable to set it as 200 mass parts - 1500 mass parts.

(polyamide acid, polyamide ester and polyimide)

The polyamic acid, polyamic acid ester, and polyimide contained in the liquid crystal alignment agent can be synthesized according to a previously known method. For example, polyamic acid can be obtained by reacting tetracarboxylic dianhydride and diamine. Polyamic acid ester can be obtained by, for example, reacting polyamic acid with an esterifying agent (such as methanol, ethanol, N,N-dimethylformamide diethyl acetal, etc.) And get. Polyimide can be obtained, for example, by dehydrating and ring-closing polyamic acid, followed by imidization. Furthermore, the polyimide preferably has an imidization rate of 20%-95%, more preferably 30%-90%. The imidization ratio is a percentage representing the ratio of the number of imide ring structures to the sum of the number of amic acid structures and the number of imide ring structures in polyimide.

Examples of tetracarboxylic acids used for polymerization include aliphatic tetracarboxylic dianhydrides such as butane tetracarboxylic dianhydride and ethylenediaminetetraacetic dianhydride; 1,2,3,4-cyclobutanetetracarboxylic Acid dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 5-(2,5 -Dioxotetrahydrofuran-3-yl)-3a,4,5,9b-tetrahydronaphthalene[1,2-c]furan-1,3-dione, 5-(2,5-dioxotetrahydrofuran- 3-yl)-8-methyl-3a,4,5,9b-tetrahydronaphthalene[1,2-c]furan-1,3-dione, 2,4,6,8-tetracarboxybicyclo[3.3 .0] Octane-2:4,6:8-dianhydride, cyclopentanetetracarboxylic dianhydride, cyclohexanetetracarboxylic dianhydride and other alicyclic tetracarboxylic dianhydride; pyromellitic dianhydride , 4,4'-(hexafluoroisopropylidene) diphthalic anhydride, p-phenylene bis(trimellitic monoester anhydride), ethylene glycol bis(trimellitic anhydride), 1,3-propanediol bis Aromatic tetracarboxylic dianhydrides, such as (trimellitic anhydride), etc., can use the tetracarboxylic dianhydride of Unexamined-Japanese-Patent No. 2010-97188 other than that. In addition, tetracarboxylic dianhydride may be used individually by 1 type, and may use it in combination of 2 or more types.

In addition, examples of the diamine used in the polymerization include aliphatic diamines such as ethylenediamine and tetramethylenediamine; p-cyclohexanediamine, 4,4'-methylenebis(cyclo Hexylamine) and other alicyclic diamines; hexadecyloxydiaminobenzene, cholestanyloxydiaminobenzene, cholestyl diaminobenzoate, cholestyl diaminobenzoate, Lanostyl diaminobenzoate, 3,6-bis(4-aminobenzoyloxy)cholestane, 3,6-bis(4-aminophenoxy)cholestane, 1,1-bis(4-((aminophenyl)methyl)phenyl)-4-butylcyclohexane, 2,5-diamino-N,N-diallylaniline, the following Formula (8-1)~Formula (8-3)

Side-chain aromatic diamines such as the compounds represented respectively; p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylamine, 4-amino Phenyl-4'-aminobenzoate, 4,4'-diaminoazobenzene, 3,5-diaminobenzoic acid, 1,5-bis(4-aminophenoxy)pentyl Alkane, bis[2-(4-aminophenyl)ethyl]adipic acid, bis(4-aminophenyl)amine, N,N-bis(4-aminophenyl)methylamine, N ,N'-bis(4-aminophenyl)-benzidine, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-bis(trifluoromethyl) -4,4'-diaminobiphenyl, 4,4'-diaminodiphenyl ether, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 4, 4'-(phenylenediisopropylidene)bisaniline, 1,4-bis(4-aminophenoxy)benzene, 4-(4-aminophenoxycarbonyl)-1-(4- Non-side chain aromatic Diamines; diaminoorganosiloxanes such as 1,3-bis(3-aminopropyl)-tetramethyldisiloxane, etc.; recorded diamines. In addition, diamine may be used individually by 1 type, and may use it in combination of 2 or more types.

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

(Polymers of monomers having polymerizable unsaturated bonds)

Regarding polymers of monomers having polymerizable unsaturated bonds (hereinafter also referred to as "polymer PAc"), examples of polymerizable unsaturated bonds contained in monomers constituting polymer PAc include: (methyl ) acryl group, vinyl group, styryl group, maleimide group, etc. Specific examples of monomers having these polymerizable unsaturated bonds include (meth)acrylic compounds such as unsaturated carboxylic acids, unsaturated carboxylic acid esters, and unsaturated polyvalent carboxylic acid anhydrides; styrene, methyl Aromatic vinyl compounds such as styrene and divinylbenzene; conjugated diene compounds such as 1,3-butadiene and 2-methyl-1,3-butadiene; N-methylmaleimide , N-cyclohexylmaleimide, N-phenylmaleimide and other maleimide compounds. In addition, the monomer which has a polymerizable unsaturated bond can be used individually by 1 type or in combination of 2 or more types.

The polymer PAc is preferably 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 other monomers. Examples of such other monomers include conjugated diene compounds, aromatic vinyl compounds, maleimide compounds, and the like. The poly(meth)acrylate preferably has 30% by mass or more derived from (meth)acrylic acid The structural unit of the compound is more preferably at least 40% by mass, still more preferably at least 50% by mass, and most preferably at least 70% by mass.

The (meth)acrylic acid-based compound used for polymerization is not particularly limited, and specific examples thereof include (meth)acrylic acid, α-ethacrylic acid, maleic acid, fumaric acid, itaconic acid, and unsaturated carboxylic acids. acid, vinyl benzoic acid, etc.; unsaturated carboxylic acid esters include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, (meth)acrylate base) allyl acrylate, cyclohexyl (meth)acrylate, tricyclo[5.2.1.0 ^2,6 ]dec-8-yl (meth)acrylate, dicyclopentyl (meth)acrylate, (meth)acrylate base) benzyl acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, trimethoxysilylpropyl (meth)acrylate, 2,2,2 (meth)acrylate -Trifluoroethyl, 2,2,3,3,3-pentafluoropropyl (meth)acrylate, methoxyethyl (meth)acrylate, N,N-dimethyl (meth)acrylate Amino ethyl ester, methoxy polyethylene glycol (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, glycidyl (meth)acrylate, (meth)acrylate Base) 3,4-epoxycyclohexylmethyl acrylate, 3,4-epoxybutyl (meth)acrylate, 4-hydroxybutyl glycidyl acrylate, etc. Toic anhydride, itaconic anhydride, cis-1,2,3,4-tetrahydrophthalic anhydride, etc. In addition, these (meth)acrylic-type compounds can be used individually by 1 type or in combination of 2 or more types.

The polymerization reaction using a (meth)acrylic compound is preferably performed by radical polymerization. As a polymerization initiator used in this polymerization reaction, for example, 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylpenta Nitrile), 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile) and other azo compounds. The usage ratio of the polymerization initiator is preferably 0.01 to 40 parts by mass relative to 100 parts by mass in total of the monomers used in the reaction.

The polymerization reaction of (meth)acrylic compound is preferably carried out in an organic solvent. Examples of the organic solvent used in this reaction include alcohols, ethers, ketones, amides, esters, and hydrocarbon compounds. Among these, it is preferable to use at least one selected from the group consisting of alcohols and ethers, and it is more preferable to use partial ethers of polyhydric alcohols. Preferable specific examples thereof include, for example, diethylene glycol methyl ether, propylene glycol monomethyl ether acetate, and the like. In addition, as an organic solvent, these can be used individually by 1 type or in combination of 2 or more types.

During the polymerization reaction of the (meth)acrylic compound, the reaction temperature is preferably set at 30° C. to 120° C., and the reaction time is preferably set at 1 hour to 36 hours. In addition, the usage-amount (a) of the organic solvent is preferably such that the total amount (b) of the monomers used in the reaction becomes 0.1% by mass to 50% by mass with respect to the total amount (a+b) of the reaction solution.

The polystyrene-equivalent number average molecular weight (Mn) measured by GPC with respect to poly(meth)acrylate becomes like this. Preferably it is 250-500,000, More preferably, it is 500-100,000, More preferably, it is 1,000-50,000.

As other components, in addition to the above, for example, compounds having at least one epoxy group in the molecule (except for compounds corresponding to the silicon-containing compound [A]), functional silane compounds (except for compounds corresponding to compound containing silicon compound [A]), antioxidant, metal chelate compound, hardening accelerator, crosslinking agent, Surfactants, fillers, dispersants, photosensitizers, etc. The compounding ratio of other components can be suitably selected according to each compound in the range which does not impair the effect of this indication.

(solvent)

The liquid crystal alignment agent disclosed in the present disclosure is prepared in the form of a solution-like composition obtained by dissolving or dispersing the polymer component and optional optional components preferably in an organic solvent. Examples of the organic solvent used include aprotic polar solvents, phenolic solvents, alcohols, ketones, esters, ethers, halogenated hydrocarbons, and hydrocarbons. The solvent component may be one of these, or a mixed solvent of two or more.

Specific examples of the organic solvent used include, for example, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 1,2-dimethyl-2-imidazolidone, γ-butyrolactone, γ-butyrolactam, N,N-dimethylformamide, N,N-dimethylacetamide, 4-hydroxy-4-methyl-2-pentanone, ethyl Glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxy propionate, ethyl ethoxy propionate, 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 di Diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diisobutyl ketone, isoamyl propionate , isopentyl isobutyrate, diisoamyl ether, ethylene carbonate, propylene carbonate, cyclohexane, octanol, tetrahydrofuran, etc. Furthermore, the hydrocarbon-based solvent not containing an imide structure can be used for the purpose of being able to realize application to plastic substrates or low-temperature calcination.

As the solvent component, it is preferable to use at least one selected from the group consisting of compounds represented by the following formulas (E-1) to (E-5) respectively, and 1 atm A solvent having a boiling point of 180° or less (hereinafter also referred to as "specific solvent"). With these specific solvents, the applicability (printability) of the liquid crystal alignment agent can be improved, and even when the film is heated at a low temperature (for example, below 200° C.), a liquid crystal alignment agent and an excellent electrical property can be obtained. It is preferable in terms of a liquid crystal element.

(In formula (E-1), R ⁴¹ is an alkyl group with 1 to 4 carbons or CH ₃ CO-, R ⁴² is an alkanediyl group with 1 to 4 carbons or -(R ⁴⁷ -O)rR ⁴⁸ -( Wherein, R ⁴⁷ and R ⁴⁸ are independently alkanediyl with 2 or 3 carbons, r is an integer of 1 to 4), R ⁴³ is a hydrogen atom or an alkyl group with 1 to 4 carbons)

(In the formula (E-2), ^R44 is an alkanediyl group with 1 to 4 carbon atoms)

(In formula (E-3), R ⁴⁵ and R ⁴⁶ are each independently an alkyl group with 1 to 8 carbons)

[Chem. 14] R ⁴⁹ -R ⁵⁰ -OH (E-4)

(In formula (E-4), R ⁴⁹ is a hydrogen atom or a hydroxyl group, when R ⁴⁹ is a hydrogen atom, R ⁵⁰ is a hydrocarbon group with 1 to 9 carbons, and when R ⁴⁹ is a hydroxyl group, R ⁵⁰ is A divalent hydrocarbon group with 1 to 9 carbons or a divalent group with an oxygen atom between the carbon-carbon bonds)

[Chem. 15]R ⁵¹ -COO-R ⁵² (E-5)

(In formula (E-5), R ⁵¹ and R ⁵² are each independently a monovalent hydrocarbon group with 1 to 6 carbons or a monovalent group with an oxygen atom between the carbon-carbon bonds)

As specific examples of specific solvents, the compounds represented by the formula (E-1) include, for example, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol methyl ether, 3-methoxy-1 - Butanol, Ethylene Glycol Monomethyl Ether, Ethylene Glycol Monoethyl Ether, Diethanol Monopropyl Ether, Ethylene Glycol-N-Butyl Ether (Butyl Cellosolve), Ethylene Glycol Dimethyl Ether, Ethylene Glycol Ether Acetate , diethylene glycol dimethyl ether, etc.; the compound represented by the formula (E-2) can include, for example, cyclobutanone, cyclopentanone, and cyclohexanone; the compound represented by the formula (E-3) is, for example, 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 Ketone, di-isobutyl ketone, trimethylnonanone, cyclopentanone, cyclohexanone, cycloheptanone, cyclooctanone, methylcyclohexanone, 2,4-pentanedione, acetonylacetone, di Isobutyl ketone, etc.; the compound represented by the formula (E-4) can include, for example, methanol, ethanol, propanol, butanol, pentanol, 3-methoxybutanol, hexanol, heptanol, octanol , furfuryl alcohol, phenol, cyclohexanol, methylcyclohexanol, 3,3,5-trimethylcyclohexanol, benzyl alcohol, diacetone alcohol and other monoalcohols or ethylene glycol, 1,2-propanediol, 1 , 3-butanediol, 2,4-pentanediol and other polyhydric alcohols; the compound represented by the formula (E-5) can include, 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-ethyl butyl ether, diethylene glycol monomethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monopropyl ether and other polyol ethers), methyl acetate, ethyl acetate, propyl acetate, n-butyl acetate, isobutyl acetate , tertiary butyl acetate, 3-methoxybutyl acetate, 2-ethylhexyl acetate, methyl acetylacetate, ethyl acetylacetate, ethylene glycol monomethyl ether acetate, diethylene glycol Monomethyl ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, dipropylene glycol monomethyl ether acetate, Glycol acetate, 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. In addition, as a specific solvent, 1 type may be used individually, and 2 or more types may be used in combination.

Relative to the total amount of the solvent used in the preparation of the liquid crystal alignment agent, specific The usage ratio of the solvent is preferably at least 10% by mass, more preferably at least 20% by mass, and still more preferably at least 50% by mass. In addition, with respect to the total amount of solvents used in the preparation of the liquid crystal alignment agent, the upper limit of the use ratio of the specific solvent is preferably set to 95% by mass or less, more preferably set to 90% by mass or less, and further preferably set to 90% by mass or less. 80% by mass or less.

The solid content concentration in the liquid crystal alignment agent (the ratio of the total mass of components other than the solvent of the liquid crystal alignment agent to the total mass of the liquid crystal alignment agent) is appropriately selected in consideration of viscosity, volatility, etc., and is preferably 1% by mass to 10% by mass % range. When the solid content concentration is less than 1% by mass, the film thickness of the coating film becomes too small, and it becomes difficult to obtain a favorable liquid crystal alignment film. On the other hand, when the solid content concentration exceeds 10% by mass, the film thickness of the coating film becomes too large, making it difficult to obtain a good liquid crystal alignment film, and the viscosity of the liquid crystal alignment agent increases, which tends to reduce the applicability. .

<<Liquid crystal alignment film and liquid crystal element>>

The liquid crystal alignment film disclosed in the present disclosure is formed from the liquid crystal alignment agent prepared in the above manner. In addition, the liquid crystal element disclosed herein 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, for example, it can be applied to TN type, STN type, VA type (including Vertical Alignment-Multi-domain Vertical Alignment (Vertical Alignment-Multi-domain Vertical Alignment, VA-MVA) type, Vertical Alignment-Patterned Vertical Alignment (Vertical Alignment-Patterned Vertical Alignment, VA-PVA) type, etc.), IPS (In-Plane Switching) type, FFS (Fringe Field Switching) type, Optically Compensated Bend (Optically Compensated Bend, OCB), Polymer continuous compounding Various modes such as Polymer Sustained Alignment (PSA) type. A liquid crystal element can be manufactured by the method including the following steps 1-3, for example. In step 1, different substrates are used depending on the desired operation mode. All operation modes in step 2 and step 3 are common.

<Step 1: Formation of coating film>

Firstly, the liquid crystal alignment agent is coated on the substrate, and the coated surface is preferably heated to form a coating film on the substrate. As the substrate, for example, glass such as float glass and soda glass; including polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polycarbonate, poly(alicyclic olefin), etc. Plastic transparent substrate. As the transparent conductive film provided on one side of the substrate, a NESA film (registered trademark of PPG Corporation of the United States) containing tin oxide (SnO ₂ ), a film containing indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ) can be used. Indium tin oxide (Indium tin oxide, ITO) film, etc. In the case of manufacturing a TN-type, STN-type, or VA-type liquid crystal element, two substrates provided with patterned transparent conductive films are used. On the other hand, when manufacturing an IPS-type or FFS-type liquid crystal element, a substrate provided with electrodes patterned into a comb-shaped shape and a counter substrate provided with no electrodes are used. The coating of the liquid crystal alignment agent on the substrate is preferably performed on the electrode formation surface by lithographic printing, flexographic printing, spin coating, roll coater or inkjet.

After applying the liquid crystal alignment agent, it is preferable to perform preheating (prebaking) for the purpose of preventing dripping of the applied liquid crystal alignment agent. The pre-baking temperature is preferably 30° C. to 200° C., and the pre-baking time is preferably 0.25 minutes to 10 minutes. Thereafter, to completely remove the solvent and optionally thermally imide the amide acid structures present in the polymer A calcination (post-bake) step is carried out for this purpose. The calcination temperature (post-baking temperature) at this time is preferably 80° C. to 300° C., and the post-baking time is preferably 5 minutes to 200 minutes. The film thickness of the film formed in this way is preferably 0.001 μm to 1 μm.

<Step 2: Alignment Processing>

When manufacturing a TN-type, STN-type, IPS-type or FFS-type liquid crystal element, the coating film formed in the above step 1 is subjected to a treatment (alignment treatment) for imparting liquid crystal alignment ability. Thereby, the alignment energy of a liquid crystal molecule is given to a coating film, and it becomes a liquid crystal alignment film. As the alignment treatment, it is possible to enumerate: a rubbing treatment in which the coating film is given liquid crystal alignment energy by rubbing the coating film in a certain direction with a roller wrapped with a cloth containing fibers such as nylon, rayon, cotton cloth, etc.; Photo-alignment treatment, such as photo-alignment treatment, which imparts liquid crystal alignment energy to the coating film by light irradiation on the coating film on it. On the other hand, in the case of producing a vertical alignment type liquid crystal element, the coating film formed in the above step 1 can be directly used as a liquid crystal alignment film, but the coating film can also be subjected to an alignment treatment.

Light irradiation for photoalignment can be performed by methods such as 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. As the radiation irradiated to the coating film, for example, ultraviolet rays and visible rays including light having a wavelength of 150 nm to 800 nm can be used. Ultraviolet rays including light having a wavelength of 200 nm to 400 nm are preferable. When the radiation is polarized, it may be linearly polarized or partially polarized. In the case where the radiation used is linearly polarized or partially polarized, the irradiation may be performed from a direction perpendicular to the substrate surface, or from an oblique direction, or These can be combined. Let the irradiation direction in the case of non-polarized radiation be an oblique direction.

As the light source used, a low-pressure mercury lamp, a high-pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, an excimer laser, etc. are mentioned, for example. The radiation dose is preferably 400J/m ² -50,000J/m ² , more preferably 1,000J/m ² -20,000J/m ² . After irradiation with light for imparting alignment energy, water, organic solvents (such as methanol, isopropanol, 1-methoxy-2-propanol acetate, butyl cellosolve, ethyl lactate, etc.) can be used Or a mixture of these is used to clean the surface of the substrate or to heat the substrate.

<Step 3: Construction of liquid crystal cell>

A liquid crystal cell is manufactured by preparing two substrates on which the liquid crystal alignment film is formed as described above, and disposing liquid crystal between the two substrates facing each other. When manufacturing a liquid crystal cell, for example, two substrates are arranged facing each other across a gap so that the liquid crystal alignment films face each other, and the peripheral parts of the two substrates are bonded together using a sealant, and the liquid crystal is injected and filled into the liquid crystal cell. A method of sealing the injection hole in the cell gap surrounded by the surface of the substrate and a sealant; a method of using a liquid crystal drop filling (one drop filling, ODF) method, etc. As the sealing agent, for example, an epoxy resin containing a curing agent and alumina balls as spacers can be used. Examples of liquid crystals include nematic liquid crystals and smectic liquid crystals, among which nematic liquid crystals are preferred. In the PSA mode (including the case where a compound (low molecular weight or polymer) having a polymerizable group is contained in the liquid crystal alignment film), after the construction of the liquid crystal cell, a voltage is applied between the conductive films of the pair of substrates. In the state, the liquid crystal cell is subjected to light irradiation treatment.

Next, if necessary, a polarizing plate is bonded to the outer surface of the liquid crystal cell to prepare a liquid crystal cell. Examples of the polarizing plate include a polarizing plate in which a polarizing film called “H film” made of polyvinyl alcohol on one side is sandwiched between cellulose acetate protective films, or a polarizing plate including the H film itself. It is formed by absorbing iodine on one side of the extended alignment.

The disclosed liquid crystal element can be effectively used in various applications, such as clocks, portable game machines, word processors, notebook personal computers, car navigation systems, video cameras, personal digital assistants (Personal Digital Assistant) , PDA), digital cameras, mobile phones, smart phones, various monitors, LCD TVs, information displays and other display devices, or dimming films, etc. In addition, the liquid crystal element formed by using the liquid crystal alignment agent disclosed herein can also be applied to a retardation film.

[Example]

Hereinafter, although an Example demonstrates concretely, this 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. In addition, the molecular weight distribution (Mw/Mn) was calculated from the obtained Mw and Mn.

Device: "GPC-101" by Showa Denko Co., Ltd.

GPC column: Combination of "GPC-KF-801", "GPC-KF-802", "GPC-KF-803" and "GPC-KF-804" manufactured by Shimadzu GLC Co., Ltd.

Mobile Phase: Tetrahydrofuran (THF)

Column temperature: 40°C

Flow rate: 1.0mL/min

Sample concentration: 1.0% by mass

Sample injection volume: 100μL

Detector: Differential refractometer

Standard material: monodisperse polystyrene

<Synthesis of Polymer>

[Example 1A]

Polymer (P-1) was synthesized according to Scheme 1 below.

Put 100.0 g of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 500 g of methyl isobutyl ketone, and 10.0 g of triethylamine into a 1000 ml three-necked flask, and mix them at room temperature. Then, drop 100 g of deionized water in 30 minutes from the dropping funnel Thereafter, mixing was performed under reflux and a reaction was performed at 80° C. for 6 hours. After completion of the reaction, the organic layer was taken out, and the organic layer was 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. An appropriate amount of methyl isobutyl ketone was added to obtain a 50 mass % solution of polyorganosiloxane (E-1) having an epoxy group.

Add 26.69g (0.3mol equivalent) of the side chain precursor (ca-1), 3.09g (0.1mol equivalent) of m-aminobenzoic acid, 2.00g of tetrabutylammonium bromide, and polyorganosiloxane into a 500ml three-necked flask. 80 g of a solution of alkane (E-1) and 239 g of methyl isobutyl ketone were stirred at 110° C. for 4 hours. After cooling to room temperature, the liquid separation and washing operation was repeated 10 times with distilled water. Thereafter, the organic layer was recovered, and concentration and NMP dilution were repeated twice by a rotary evaporator to obtain a 15% by mass NMP solution of the polymer (P-1) intermediate. After adding 0.44 g (0.1 mol equivalent) of trimellitic anhydride to 50 g of the intermediate solution, the solid content concentration was prepared using NMP to be 10% by mass, and stirred at room temperature for 4 hours, thereby An NMP solution of polymer (P-1) was obtained.

[Example 2A～Example 12A and Comparative Synthesis Example 1～Comparison Synthesis Example 4]

Polymerization was carried out in the same manner as in Example 1A, except that the types and amounts of the compounds used in the synthesis were those shown in Table 1 below, to obtain polymers (P-2) to polymers (P-12 ), each polymer of polymer (R-1) ~ polymer (R-4).

[Table 1]

The numerical value in Table 1 shows the usage ratio (mol %) of carboxylic acid and carboxylic anhydride with respect to the number of epoxy groups which epoxy group-containing polyorganosiloxane has. The abbreviations of the compounds in Table 1 are as follows.

(side chain precursor [C])

ca-1~ca-5: Compounds represented by the following formula (ca-1) ~ formula (ca-5), respectively

[chemical 17]

(Amine-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.

[chemical 18]

In a 1000ml three-necked flask, 90.0g of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 7.3g of 3-aminopropyltrimethoxysilane, 500g of methyl isobutyl ketone and 10.0 g of triethylamine was mixed at room temperature. Then, after adding 100 g of deionized water dropwise from the dropping funnel over 30 minutes, it was mixed under reflux and reacted at 80° C. for 6 hours. After completion of the reaction, the organic layer was taken out, and the organic layer was 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. An appropriate amount of methyl isobutyl ketone was added to obtain a 50 mass % solution of polyorganosiloxane (E-2) having epoxy groups and amino groups.

In a 500ml three-necked flask, add 26.69g (0.3mol equivalent) of side chain precursor (ca-1), 2.00g of tetrabutylammonium bromide, 80g of solution containing polyorganosiloxane (E-2) and methyl iso 239 g of butyl ketone was stirred at 110° C. for 4 hours. After cooling to room temperature, the liquid separation and washing operation was repeated 10 times with distilled water. Thereafter, the organic layer was recovered, and concentration and NMP dilution were repeated twice using a rotary evaporator to obtain a 15% by mass NMP solution of the polymer (P-13) intermediate. After adding 0.45 g (0.1 mol equivalent) of trimellitic anhydride to 50 g of the intermediate solution, it was prepared using NMP so that the solid content concentration became 10% by mass, and then carried out at room temperature for 4 hours. Stirring while stirring, thereby obtaining the NMP solution of the polymer (P-13).

[Example 14A]

Polymer (P-14) was synthesized according to Scheme 3 below.

Add 26.69g (0.3mol equivalent) of the side chain precursor (ca-1), 3.09g (0.1mol equivalent) of m-aminobenzoic acid, 2.00g of tetrabutylammonium bromide, and polyorganosiloxane into a 500ml three-necked flask. 80 g of a solution of alkane (E-1) and 239 g of methyl isobutyl ketone were stirred at 110° C. for 4 hours. After cooling to room temperature, the liquid separation and washing operation was repeated 10 times with distilled water. Thereafter, the organic layer was recovered, and concentrated twice and diluted with NMP by a rotary evaporator to obtain a polyorganosiloxane having an epoxy group and a functional group (referred to as "polymer (R-1) ”) of 15% by mass NMP solution.

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

[Synthesis Example 1]

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

[Synthesis Example 2]

Under nitrogen, 16.0 g (113 mmol) of glycidyl methacrylate and 4.0 g (46.5 mmol) of methacrylic acid, and 2,2' - 0.6 g (2.4 mmol) of azobis(2,4-dimethylvaleronitrile), 1.0 g (4.2 mmol) of 2,4-diphenyl-4-methyl-1-pentene as a chain transfer agent , and 86.4 g of NMP as a solvent were polymerized at 70° C. for 5 hours to obtain the target polymer (this is referred to as “polymer (PM-1)”). About the obtained polymer (PM-1), the weight average molecular weight Mw measured by the polystyrene conversion by GPC was 20000, and the molecular weight distribution Mw/Mn was 2.1.

[Comparative Synthesis Example 5A]

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

Add 10.0 g of 3,4-epoxycyclohexylmethyl methacrylate, 20.1 g (1 mol equivalent) of side chain precursor (ca-1) and 500 g of cyclopentane into a 1000 mL eggplant-shaped flask with a stirring bar and 1.64 g (0.1 mol equivalent) of tetrabutylammonium bromide, and stirred at 110° C. for 4 hours. Then, 300 g of cyclohexane and 400 g of cyclopentanone were added to the reaction liquid, and liquid separation washing was performed 5 times with 400 g of distilled water. Thereafter, the organic layer was slowly concentrated with a rotary evaporator until the inner volume became 50 g, and the white solid deposited on the way was recovered by filtration. Compound (MI-6) 23.0 g was obtained by vacuum-drying the said white solid.

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

<Production and Evaluation of Liquid Crystal Display Devices (1)>

[Example 1B]

1. Preparation of liquid crystal alignment agent (AL-1)

NMP and butyl cellosolve (Butyl Cellosolve, BC) as a solvent were added to 100 parts by mass of the polymer (P-1) obtained in the above-mentioned Example 1A as the polymer [P] to prepare a solvent composition of NMP /BC=50/50 (mass ratio), a solution having a solid content concentration of 4.0% by mass. The liquid crystal alignment agent (AL-1) was prepared by filtering the solution through a filter with a pore size of 1 μm.

2. Manufacture of optical vertical type liquid crystal display element

The prepared liquid crystal alignment agent (AL-1) was coated on the transparent electrode surface of the glass substrate with transparent electrodes including the ITO film using a spinner, and pre-baked on a heating plate at 80° C. for 1 minute. Then, it heated at 230 degreeC for 1 hour in the oven which replaced the inside of a chamber with nitrogen, and formed the coating film with a film thickness of 0.1 micrometer. Next, using a Hg-Xe lamp and a Glan-Taylor fluoride, the surface of the coating film was irradiated with 1,000 J/m ² of polarized ultraviolet light including a bright line of 313 nm from a direction inclined 40° from the normal line of the substrate to form a liquid crystal alignment membrane. Repeat the same operation to make a pair (two pieces) of substrates with liquid crystal alignment films.

The epoxy resin loaded with alumina balls with a diameter of 3.5 μm was bonded by screen printing The adhesive is coated on the outer periphery of the surface with the liquid crystal alignment film of one of the substrates, and then the liquid crystal alignment film faces of the pair of substrates are facing each other, and the projection direction of the optical axis of the ultraviolet rays of each substrate on the substrate surface is Pressure bonding was performed in an anti-parallel manner, and the adhesive was thermally cured at 150° C. for 1 hour. Next, after filling the gap between the substrates from the liquid crystal injection port with a negative liquid crystal (MLC-6608, manufactured by Merck), the liquid crystal injection port was sealed with an epoxy-based adhesive. Furthermore, in order to remove the flow alignment at the time of liquid crystal injection, this was heated at 130 degreeC, and it cooled gradually to room temperature. Next, the polarizers are attached to the outer sides of the substrate with their polarization directions perpendicular to each other and at an angle of 45° to the projection direction of the ultraviolet light of the liquid crystal alignment film on the substrate surface, thereby manufacturing a liquid crystal display element.

3. Evaluation of liquid crystal alignment

For the manufactured liquid crystal display element, the voltage of 5V was turned on through optical microscope observation. The presence or absence of an abnormal domain (domain) in the light and dark change at the time of turning off (ON.OFF) (applied.Release), let the case of no abnormal domain be "A", and the case of some abnormal domains be "B". , the liquid crystal alignment was evaluated by setting the case where there were abnormal domains as a whole as "C". As a result, the liquid crystal alignment was "A" in the above-described examples.

4. Evaluation of solvent resistance of liquid crystal alignment film

After coating the liquid crystal alignment agent (AL-1) on the silicone substrate using a spinner, prebaking was performed on a hot plate at 90° C. for 2 minutes to form a coating film with a film thickness of 1.0 μm. The obtained coating film was heated on a hot plate at 230° C. for 30 minutes. After immersing the obtained film in NMP for 1 minute, it dried at 100 degreeC for 5 minutes. Calculate the change rate ΔDnmp of the film thickness before and after immersion by the following formula (1). ΔDnmp evaluates solvent resistance.

△Dnmp=[((film thickness before immersion)-(film thickness after immersion))/(film thickness before immersion)]×100…(1)

The evaluation was made as "A" when the rate of change ΔDnmp was -2% to 2%, in the range of -5% to less than -2%, or in the range of more than 2% to 5% It was performed as "B" when it was within, and as "C" when it was greater than 5% or less than -5%. In the above Examples, the solvent resistance "A" was evaluated.

5. Evaluation of voltage retention rate (VHR)

About the liquid crystal display element manufactured above, after the voltage of 5V was applied for the application time of 60 microseconds, and the interval of 167 milliseconds, the voltage retention rate from the start of application release to 167 milliseconds after was measured. As a measurement device, VHR-1 manufactured by Toyo Technology Co., Ltd. was used. At this time, the case where the voltage retention rate is 90% or more is set as "A", the case of 80% or more and less than 90% is set as "B", and the case of 50% or more and less than 80% is "B". C" and set the case of less than 50% to "D". As a result, the voltage retention rate was evaluated as "B" in the above-described examples.

6. Evaluation of thermal reliability

About the liquid crystal display element produced above, it heated for 500 hours in the oven set at 110 degreeC. The voltage retention rate before and after heating was measured by the said method, and the fall of the voltage retention rate after heating was evaluated. At this time, reduce the voltage retention rate to 20% or less The case below is set as "A", the case of 20% or more and less than 40% is set as "B", and the case of 40% or more is set as "C". As a result, the thermal reliability was evaluated as "A" in the above Examples.

7. Evaluation of printability

Regarding the prepared liquid crystal alignment agent (AL-1), use a flat-plate liquid crystal alignment film printer (manufactured by Nippon Photo Printing Co., Ltd.), and apply it to the transparent electrode surface of a glass substrate with a transparent electrode comprising an ITO film. After removing the solvent, heat on a hot plate at 80°C for 1 minute, and then heat on a hot plate at 200°C for 10 minutes to form ) with an average film thickness of 800Å.

The coating film was observed with an optical microscope at a magnification of 20 times, and the presence or absence of printing unevenness and pinholes was checked. The evaluation was made "A" when both uneven printing and pinholes were not observed, "B" when at least one of uneven printing and pinholes were observed partly, and "B" when all the uneven printing and pinholes were observed. The case of at least one of printing unevenness and pinholes was set to "C". As a result, the printability was evaluated as "B" in the above-mentioned Examples.

[Example 2B~Example 15B and Comparative Example 1B~Comparative Example 4B, Comparative Example 7B]

Except that the preparation composition was changed as shown in the following Table 2, it prepared with the same solid content concentration as Example 1B, and obtained the liquid crystal alignment agent respectively. Moreover, using each liquid crystal aligning agent, the optical vertical type liquid crystal display element was manufactured similarly to Example 1B, and various evaluations were performed using the obtained liquid crystal display element. The results are collectively shown in Table 2 below. Furthermore, in Table 2, regarding compound [A], other polymers and additives The value of the additive, in Example 1B, Example 8B, Comparative Example 1B, and Comparative Example 2B, represents the use ratio [parts by mass] of each compound relative to the total of 100 parts by mass of the polymer component used in the preparation of the liquid crystal alignment agent, Examples 2B~7B, Example 9B, Example 10B, Example 11B~Example 18B and Comparative Example 3B~Comparative Example 7B represent the polyamic acid (PAA- 1) The usage ratio [mass parts] of a total of 100 mass parts, Example 11B shows the usage ratio [mass parts] of each compound to a total of 100 mass parts of the polymer (PM-1) used in the preparation of the liquid crystal alignment agent ].

<Production and Evaluation of Liquid Crystal Display Devices (2)>

[Example 16B]

1. Preparation of liquid crystal alignment agent (AL-16)

The polyamic acid (PAA-1) obtained in the above-mentioned Synthesis Example 1 as another polymer was added 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, and 3-methoxyl-1-butanol (MB), NMP and butyl cellosolve (BC) as solvent, and make solvent composition and become MB/NMP/BC=30/20/50 (mass Ratio), a solution with a solid content concentration of 4.0% by mass. The liquid crystal alignment agent (AL-16) was prepared by filtering the solution through a filter with a pore size of 1 μm.

2. Manufacture of optical horizontal type liquid crystal display element

The prepared liquid crystal alignment agent (AL-16) was coated on the transparent electrode surface of the glass substrate with transparent electrodes including the ITO film using a spinner, and pre-baked on a heating plate at 80° C. for 1 minute. Then, it heated at 230 degreeC for 1 hour in the oven which replaced the inside of a chamber with nitrogen, and formed the coating film with a film thickness of 0.1 micrometer. Next, using a Hg-Xe lamp and Glan-Taylor fluoride, the surface of the coating film was irradiated with 1,000 J/m ² of polarized ultraviolet light including a bright line of 313 nm from a direction inclined at 90° from the normal line of the substrate to form a liquid crystal alignment membrane. Repeat the same operation to make a pair (two pieces) of substrates with liquid crystal alignment films.

An epoxy resin adhesive containing alumina balls with 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 crystals of the pair of substrates were aligned. The film faces faced each other, and pressure bonding was performed so that the optical axis of ultraviolet light of each substrate on the substrate surface was horizontally bonded, and the adhesive was thermally cured at 150° C. for 1 hour. Next, after filling the gap between the substrates from the liquid crystal injection port with a positive type liquid crystal (MLC-7028-100, manufactured by Merck), the liquid crystal injection port was sealed with an epoxy-based adhesive. Furthermore, in order to remove the flow alignment at the time of liquid crystal injection, this was heated at 130 degreeC, and it cooled gradually to room temperature. Next, the polarizers are attached to the outer sides of the substrate at an angle of 90° to the projection direction of the ultraviolet light of the liquid crystal alignment film, the polarization directions of which are perpendicular to each other, and the liquid crystal display element is manufactured.

3. Evaluation

About the optical horizontal type liquid crystal display element manufactured above, the liquid crystal orientation, solvent resistance, voltage retention (VHR), thermal reliability, and printability were evaluated similarly to Example 1B. The results are shown in Table 2 below.

[Comparative Example 5B]

Except that the deployment composition is changed as shown in the following table 2, with embodiment 16B The same solid content concentration was prepared to obtain liquid crystal alignment agents respectively. Moreover, using each liquid crystal alignment agent, it manufactured the light horizontal type liquid crystal display element similarly to Example 16B, and performed various evaluation similarly to Example 1B using the obtained liquid crystal display element. The results are shown in Table 2 below.

<Production and Evaluation of Liquid Crystal Display Devices (3)>

[Example 17B]

1. Preparation of liquid crystal alignment agent (AL-17)

A liquid crystal alignment agent (AL-17) was prepared at the same solid content concentration as in Example 16B, except that the prepared composition was changed as shown in the following Table 2.

2. Manufacture of PSA type liquid crystal display elements

The prepared liquid crystal alignment agent (AL-17) was coated on the transparent electrode surface of the glass substrate with transparent electrodes including the ITO film using a spinner, and pre-baked on a heating plate at 80° C. for 1 minute. Then, it heated at 230 degreeC for 1 hour in the oven which replaced the inside of a chamber with nitrogen, and formed the coating film with a film thickness of 0.1 micrometer. Repeat the same operation to make a pair (two pieces) of substrates with liquid crystal alignment films.

An epoxy resin adhesive containing alumina balls with 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 crystals of the pair of substrates were aligned. With the film side facing each other, the adhesive was thermally cured at 150°C for 1 hour. Next, after filling the gap between the substrates from the liquid crystal injection port with a negative liquid crystal (MLC-6608, manufactured by Merck), the liquid crystal injection port was sealed with an epoxy-based adhesive. Furthermore, in order to remove the flow alignment at the time of liquid crystal injection, this was heated at 130 degreeC, and it cooled gradually to room temperature.

Next, AC 10V at a frequency of 60 Hz is applied between the pair of electrodes, and the liquid crystal is driven, and ultraviolet rays are irradiated at an irradiation dose of 100,000 J/m ² using an ultraviolet irradiation device using a metal halide lamp as the light source. In addition, the said irradiation amount is the value measured using the light meter which measures based on wavelength 365nm. Thereafter, the polarizing plates are attached to the outer sides of the substrate with their polarization directions perpendicular to each other and at an angle of 45° to the projection direction of the ultraviolet light of the liquid crystal alignment film on the substrate surface, thereby manufacturing a liquid crystal display element.

3. Evaluation

About the PSA type liquid crystal display element manufactured above, the liquid crystal orientation, solvent resistance, voltage retention (VHR), thermal reliability, and printability were evaluated similarly to Example 1B. The results are shown in Table 2 below.

[Example 18B and Comparative Example 6B]

Except that the preparation composition was changed as shown in the following Table 2, preparation was carried out at the same solid content concentration as in Example 16B, and liquid crystal alignment agents were respectively obtained. In addition, a liquid crystal display element was produced in the same manner as in Example 17B using each liquid crystal alignment 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.

In Table 2, the numerical value of a solvent shows the compounding ratio (mass part) of each solvent with respect to the total amount of 100 mass parts of the solvent used for preparation of a liquid crystal alignment agent. The abbreviations of the solvents are 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 ether

PGMEA: Propylene Glycol Monomethyl Ether Acetate

From the results of the above examples, it can be seen that according to Example 1B to Example 18B using the liquid crystal alignment agent containing the silicon-containing compound [A], a liquid crystal display element having excellent thermal reliability can be obtained. In addition to thermal reliability, the obtained liquid crystal display element is also excellent in liquid crystal alignment and voltage retention, and the liquid crystal alignment film is also excellent in solvent resistance and printability. On the other hand, compared with Examples, the thermal reliability of the comparative example 1B - the comparative example 7B which used the liquid crystal alignment agent which does not contain a silicon-containing compound [A] was inferior. In addition, not only the thermal reliability, but also the comprehensive observation of solvent resistance, voltage retention rate and printability, it is also well-balanced in the examples that have been improved.

This disclosure is described based on the embodiments, and it should be understood that the present disclosure is not limited to the above embodiments or configurations. This disclosure also includes various modified examples or modifications within an equivalent range. In addition, various combinations or forms, and further combinations or forms including only one element, more than one, or less than one of these elements are also included in the category or scope of thought of the present disclosure.

Claims (11)

A liquid crystal alignment agent, which contains a silicon-containing compound having a cyclic ether group and a functional group B reactive with the cyclic ether group, wherein the functional group B is a carboxyl group. The liquid crystal alignment agent described in claim 1 of the patent application, wherein the functional group B is a functional group that reacts with a cyclic ether group by heat. The liquid crystal alignment agent as described in item 1 or item 2 of the patent application, wherein the silicon-containing compound is a polymer [P] having a siloxane skeleton. The liquid crystal alignment agent as described in claim 3 of the patent application, wherein the polymer [P] has a photoalignment group. The liquid crystal alignment agent as described in claim 3 of the patent application, wherein the polymer [P] has an alignment display site for aligning liquid crystal molecules. The liquid crystal alignment agent as described in claim 3 of the patent application, wherein the polymer [P] has groups containing carbon-carbon unsaturated bonds. The liquid crystal alignment agent as described in claim 3 of the patent application, further comprising a polymer [Q] different from the polymer [P]. The liquid crystal alignment agent as described in item 7 of the patent application, wherein the polymer [Q] is selected from polyamic acid, polyamic acid ester, polyimide and monomers with polymerizable unsaturated bonds At least one of the group consisting of polymers. A liquid crystal alignment film, which is formed by the liquid crystal alignment agent described in any one of items 1 to 8 of the patent application. A liquid crystal element, which is equipped with the liquid crystal alignment film as described in item 9 of the scope of application. A polyorganosiloxane has a cyclic ether group and a functional group B reacting with the cyclic ether group, wherein the functional group B is a carboxyl group.