TW201348300A - Liquid crystal aligning agent, liquid crystal aligning film, liquid crystal display device and polymer - Google Patents

Abstract

A liquid crystal aligning agent, a liquid crystal aligning film, a liquid crystal display device and a polymer are provided, which forms a liquid crystal aligning film capable of carrying out high quality display with a wide viewing angle by utilizing a photo alignment method, and shows excellent inkjet coating properties. The liquid crystal aligning agent is (characterized by including a polymer having a structure represented by formula (A) below. In the formula (A), B represents a group including a structure of cinnamic acid, a represents an integer of 1 to 4, and b and c each independently represents an integer of 0 to 8, wherein b+c ≥ 3 when a equals 1, b+c ≥ 2 when a is an integer of 2 to 4, and ''*'' represents a bonding hand.)

Description

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

This invention relates to a liquid crystal alignment agent. Specifically, it is a liquid crystal alignment agent which has a high coating property and can provide a liquid crystal display element excellent in liquid crystal alignment property and electrical characteristics.

In the liquid crystal display device, a liquid crystal alignment film is provided on the surface of the substrate in order to align the liquid crystal molecules in a predetermined direction with respect to the substrate surface. The liquid crystal alignment film is usually formed by a method (friction method) in which the surface of the organic film formed on the surface of the substrate is wiped in one direction by a cloth material such as rayon. However, when the liquid crystal alignment film is formed by the rubbing treatment, dust or static electricity is likely to be generated in the rubbing step. Therefore, there is a problem that dust adheres to the surface of the alignment film to cause display failure, and in addition, a thin film transistor is provided. In the case of the substrate of the (Thin Film Transistor, TFT) device, there is also a circuit failure of the TFT element due to the generated static electricity, which causes a decrease in the yield of the product. question. Therefore, as another method of aligning the liquid crystal in the liquid crystal cell, a photo-alignment method in which a liquid crystal alignment capability is imparted by irradiating a radiation-sensitive or non-polarized radiation to a radiation-sensitive organic thin film formed on the surface of the substrate has been proposed (see Patent Document 1 to Patent Document 4).

As the liquid crystal display element, liquid crystal display having a vertical electric field type liquid crystal cell such as a twisted nematic (TN) type, a super twisted nematic (STN) type, or a vertical alignment type (VA) type In addition to the elements, it is known that an In-Plane Switching (IPS) type or a Fringe Field Switching (FFS) type forms electrodes on only one side of a pair of oppositely disposed substrates, and A liquid crystal display device of a transverse electric field type in which an electric field is generated in a direction in which the substrates are parallel (Patent Documents 5 to 7). This lateral electric field type liquid crystal display element has a wider viewing angle characteristic than a vertical electric field type liquid crystal display element, and is capable of high-quality display. In the liquid crystal display device of the transverse electric field type, since the liquid crystal molecules respond to the electric field only in the direction parallel to the substrate, the refractive index change in the long-axis direction of the liquid crystal molecules is not a problem, and the contrast observed by the observer even when the viewing angle is changed As well as the change in the shade of the display color, high-quality display can be performed regardless of the angle of view. In order to obtain such an advantageous effect, it is advantageous that the incident angle dependency of the incident polarized light is small, and therefore the pretilt angle in the initial alignment characteristic when the liquid crystal display element of the transverse electric field type is expected to be not applied with an electric field is low.

In the liquid crystal display device of the transverse electric field type, in order to impart the liquid crystal alignment property to the liquid crystal alignment film, the disadvantage of the above-described rubbing method is avoided, and it is desirable to utilize the optical alignment. law. However, the liquid crystal alignment agent which can be applied to the above-mentioned photo-alignment method contains an aromatic structure in a large ratio in order to impart photosensitivity to the polymer contained therein. However, when a liquid crystal alignment film containing an aromatic structure in a large proportion is used, the pretilt angle is inevitably increased, and the advantageous effects as described above in the lateral electric field type display element are impaired.

However, in recent years, the popularity of liquid crystal televisions has continued to advance, and it has been operating at a larger production line than before, and the substrate has been enlarged. The advantage of increasing the size of the substrate is as follows. Since the panel has one or more panels, the step time can be reduced and the cost can be reduced, or the liquid crystal display element itself can be increased in size. The disadvantage of the enlargement of the substrate is as follows. It is difficult to ensure the uniformity of printing of the liquid crystal alignment agent by the previous offset printing.

In order to solve this problem, an inkjet printing method has been studied and it has been put into practical use (Non-Patent Document 1). Advantages of the inkjet printing method include the following: since only a necessary amount of liquid is used, efficient use of the liquid crystal alignment agent can be expected, and since it is not necessary to exchange or clean the printing plate, it is easy to maintain and can be correspondingly Various panel sizes. On the other hand, the following disadvantages are pointed out: there is coating unevenness caused by an error in solvent removal conditions after printing, and it is easy to cause unevenness in film thickness between nozzles, nozzles, etc.; There is a problem with the yield.

[Previous Technical Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2003-307736

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2004-163646

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2002-250924

[Patent Document 4] Japanese Patent Laid-Open Publication No. 2004-83810

[Patent Document 5] US Patent No. 5,958,333

[Patent Document 6] Japanese Patent Laid-Open Publication No. SHO 56-91277

[Patent Document 7] Japanese Patent Laid-Open Publication No. 2008-46184

[Patent Document 8] Japanese Patent Laid-Open Publication No. 2010-97188

[Non-patent literature]

[Non-Patent Document 1] KONICA MINOLTA TECHNOLOGY REPORT Volume 3 (2006)

The present invention has been made to solve the above-described situation.

An object of the present invention is to provide a liquid crystal alignment agent which can exhibit the advantageous effects as described above in a liquid crystal display device of a transverse electric field type, and exhibits excellent inkjet coating properties. The liquid crystal alignment film can be formed with high yield.

According to the present invention, the above objects and advantages of the present invention are as follows The liquid crystal alignment agent is characterized by containing a polymer having a structure represented by the following formula (A).

[Chemical 1]

(In the formula (A), B is a group containing a cinnamic acid structure, a is an integer of 1 to 4, and b and c are each independently an integer of 0 to 8, wherein when a is 1, b+c≧ 3. When a is an integer of 2 to 4, b+c≧2, and "*" indicates a binding key.)

The liquid crystal alignment agent of the present invention is excellent in printability, and in the case of applying an inkjet coating method, a liquid crystal alignment film having excellent uniformity can be formed.

Further, the liquid crystal alignment agent of the present invention can provide a liquid crystal display element having a wide viewing angle characteristic and capable of high-quality display by a photo-alignment method. When the liquid crystal alignment agent of the present invention is applied to a liquid crystal display device of a transverse electric field type, this effect is extremely advantageously exhibited.

Therefore, the liquid crystal alignment agent of the present invention can be favorably applied to a production line using the most recent liquid crystal display element of a large-sized substrate, and is particularly suitable for producing a liquid crystal display element of a transverse electric field type by a photo-alignment method.

Hereinafter, the present invention will be described in detail.

The liquid crystal alignment agent of the present invention contains a polymer having the structure represented by the above formula (A) (hereinafter referred to as "specific polymer").

The group including the cinnamic acid structure, that is, the group B in the above formula (A), for example, a group represented by the following formula (B-1) and formula (B-2), and the like.

(R in the formula (B-1) is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, a phenyl group or a phenoxy group; R ¹ in the formula (B-2) is an alkyl group having 1 to 10 carbon atoms, and R ² is an alkylene group having 2 to 10 carbon atoms, a divalent aromatic group having 6 to 18 carbon atoms, and a carbon number of 3 to 12 a divalent alicyclic group, a divalent condensed cyclic group having 11 to 18 carbon atoms or a heterocyclic group having 5 or 6 ring members, and Z ² and Z ³ are each independently a single bond, an oxygen atom, or -COO -or-OCO-, e is an integer from 0 to 3; and "+" means a binding key.)

Examples of the alkyl group of R in the above formula (B-1) include a methyl group, an ethyl group, a 1-propyl group, a 2-propyl group, a n-butyl group, a t-butyl group, a pentyl group and the like; and an alkoxy group, for example. Examples thereof include a methoxy group, an ethoxy group, a 1-propoxy group, and a n-butoxy group; and examples of the cycloalkyl group include a cyclohexyl group and the like.

Examples of the alkyl group of R ¹ in the above formula (B-2) include a methyl group, an ethyl group, a propyl group, a butyl group, and a pentyl group. Preferably, e in the formula (B-2) is 0, and the group Z ³ is an oxygen atom or -COO- (wherein the carbon atom is on the side -(Z ² -R ² ) _e - side).

Specific examples of the group B in the above formula (A), the group represented by the above formula (B-1) is, for example, the following formula

(In the above formula, "+" represents a group represented by a bond), and the group represented by the above formula (B-1), for example, the following formula

(In the above formula, "+" represents a group represented by a bond, respectively). In the above formula (A), it is preferable that the value of b+c when a is 1 is an integer of 3 to 6, and the value of b+c when a is 2 to 4 is 2 or 3.

Divalent group in the above formula (A)

[Chemical 5] (In the above formula, specific examples in which a, b, and c are the same meanings as a, b, and c in the above (A)) include, for example, -((CH ₂ ) ₂ -O) ₂ -, -( (CH ₂ ) ₂ -O) ₃ -, -((CH ₂ ) ₃ -O)-, -((CH ₂ ) ₄ -O)-, -((CH ₂ ) ₅ -O)-, -(( CH ₂ ) ₆ -O)-, -((CH ₂ ) ₂ -C(CH ₃ )HO)-, -((CH ₂ -C(CH ₃ )H-)-O) ₂ -, etc.

The content of the structure represented by the above formula (A) in the specific polymer is preferably 1.0 × 10 ^-4 mol / g or more, more preferably 3.0 × 10 ^-4 mol / g - 2.0 × 10 ^-3 The ear/g is particularly preferably 5.0 x 10 ^-4 mol/g to 2.0 x 10 ^-3 mol/g.

The specific polymer of the present invention may be, for example, polylysine, a ruthenium polymer of polylysine, a polyphthalate, a polyorganosiloxane, a polyester, a polyamine, a polyoxyalkylene. , cellulose derivatives, polyacetals, polystyrene or derivatives thereof, poly(styrene-phenylmethyleneimine) or derivatives thereof, poly(meth)acrylates, polyfunctional carboxylic acids A reactant with a polyfunctional epoxy compound or the like. Among these polymers, at least one selected from the group consisting of polylysine and a quinone imidized polymer is preferred.

The polyglycolic acid which is a specific polymer of the present invention can, for example, be transmissive with a tetracarboxylic dianhydride containing a tetracarboxylic dianhydride having a structure represented by the above formula (A), a reaction with a diamine, or a tetracarboxylic dianhydride. And two containing a diamine having the structure represented by the above formula (A) The ruthenium iodide polymer of polyglycine which is a specific polymer of the present invention can be synthesized, for example, by dehydration ring closure of the above polyamic acid.

The specific polymer of the present invention is preferably selected from the group consisting of polylysine obtained by reacting a tetracarboxylic dianhydride with a diamine containing a diamine having the structure represented by the above formula (A), and the polyamic acid. At least one of the group consisting of quinone imidized polymers.

Examples of the tetracarboxylic dianhydride include aliphatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, and aromatic tetracarboxylic dianhydride. Specific examples of the compound include, for example, butane tetracarboxylic dianhydride; and the alicyclic tetracarboxylic dianhydride: 2,3,5-tricarboxycyclopentyl acetic acid Dihydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3 , 4-cyclobutane tetracarboxylic dianhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[ 1,2-c]furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-8-methyl-5-(tetrahydro-2,5-dioxo-3 -furyl)-naphtho[1,2-c]furan-1,3-dione, 3,5,6-tricarboxy-2-carboxymethylnorbornane-2; 3,5;6-di Anhydride, 2,4,6,8-tetracarboxybicyclo[3.3.0]octane-2; 4,6;8-dianhydride, 3-oxabicyclo[3.2.1]octane-2,4-di Keto-6-spiro-3'-(tetrahydrofuran-2',5'-dione), 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclo Hexene-1,2-dicarboxylic anhydride, 4,9-dioxatricyclo[5.3.1.0 ^2,6 ]undecane-3,5,8,10-tetraone, etc.; aromatic tetracarboxylic acid Examples of the anhydride include 3,3', 4,4'-benzophenonetetracarboxylic dianhydride, pyromellitic dianhydride, and the like; in addition, Patent Document 8 (Japanese Patent Application) can be used. Publication No. 2010-97188 tetracarboxylic dianhydride) is described.

As the tetracarboxylic dianhydride for synthesizing the specific polymer of the present invention, it is preferred that these polymers contain at least one selected from the group consisting of alicyclic tetracarboxylic dianhydride and aromatic tetracarboxylic acid. Particularly, it is particularly preferable to contain at least one selected from the group consisting of the following compounds (hereinafter referred to as "specific tetracarboxylic dianhydride"): 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 1, 2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutane Alkane tetracarboxylic dianhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-c Furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-8-methyl-5-(tetrahydro-2,5-dioxo-3-furanyl)- Naphtho[1,2-c]furan-1,3-dione, 3,5,6-tricarboxy-2-carboxymethylnorbornane-2; 3,5;6-dianhydride, 2,4 6,6-tetracarboxybicyclo[3.3.0]octane-2; 4,6;8-dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride and pyromelli-4 Formic acid dianhydride. The tetracarboxylic dianhydride used for the synthesis of the specific polymer of the present invention is preferably contained in an amount of 80 mol% or more, more preferably 90 mol%, based on the above specific tetracarboxylic dianhydride with respect to all of the tetracarboxylic dianhydride. the above.

The tetracarboxylic dianhydride used for the synthesis of the above polyamic acid preferably contains only a specific tetracarboxylic dianhydride.

The diamine preferably used for synthesizing the specific polymer of the present invention contains a diamine having the structure represented by the above formula (A).

The diamine having a structure represented by the above formula (A) is, for example, the following formula (A-1)

[Chemical 6]

(In the formula (A-1), B, a, b, and c are each a compound represented by the same meaning as B, a, b, and c in the above formula (A)). In the above formula (A-1), the two amino groups bonded to the benzene ring are preferably at the 2,4-position or the 3,5-position relative to the other groups.

Specific examples of the compound represented by the above formula (A-1) include a case where a is 1, and b is 3, and c is 0.

The compound or the like represented by each; when a is 1, b is 4, and c is 0, for example, the following formula

The compound represented by the above, etc.; a is 1, b is 5, and c is 0, for example, the following formula

The compound represented by each, etc.; a is 1, b is 6 and c is 0, for example, the following formula

The compound represented by each of them; when a is 1, b is 2, and c is 1, the following formula is exemplified.

The compound represented by each, etc.; a is 2, b is 2, and c is 0, for example, the following formula is mentioned

The compound represented by each of them; when a is 2, b is 1, and c is 1, the following formula is exemplified.

The compound represented by the above; when a is 3, b is 2, and c is 0, for example, the following formula

Compounds and the like indicated respectively.

The compound represented by the above formula (A-1) can be synthesized by appropriately combining a common method of synthesizing an organic compound.

In the case where the group B is a group represented by the above formula (B-1), it can be synthesized, for example, by first passing through a substituted halogenated benzene having a desired group R and acrylic acid. The Heck reaction gives a substituted cinnamic acid having the desired group R. Then, the substituted cinnamic acid is given to the following formula (A-OH)

(In the formula (A-OH), the diol compound represented by a, b, and c in the same meaning as a, b, and c in the above formula (A-1) is reacted and esterified, and then Dehydrofluorination condensation reaction of dinitrofluorobenzene, and further hydrogenation of a nitro group by a suitable hydrogenation catalyst system, whereby the group represented by the above formula (B-1) can be obtained as the above formula (A-1) Compound of group B.

On the other hand, in the case where the group B is a group represented by the above formula (B-2), it can be synthesized, for example, by first passing through an acrylate having a desired group R ¹ and 4-halogenation. The heck reaction of benzoic acid gives a 4-carboxycinnamate compound having the desired group R ¹ . Then, the 4-carboxycinnamate compound is reacted with the diol compound represented by the above formula (A-OH) to be esterified, and then subjected to dehydrofluorination condensation reaction with dinitrofluorobenzene, and further appropriate hydrogenation is carried out. The catalyst is obtained by hydrogenating a nitro group, whereby a compound having the group represented by the above formula (B-2) as the group B in the above formula (A-1) can be obtained.

The diamine used for the synthesis of the specific polymer of the present invention may be the only one represented by the above formula (A-1), or another diamine may be used in combination therewith.

Examples of the other diamine which may be used herein include an aliphatic diamine, an alicyclic diamine, an aromatic diamine (excluding the compound represented by the above formula (A-1)), and a diaminoorganooxynitride. Wait. Specific examples of the diamines include, for example, 1,1-m-xylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, and hexa Methyldiamine or the like; examples of the alicyclic diamine include 1,4-diaminocyclohexane, 4,4'-methylenebis(cyclohexylamine), and 1,3-bis(aminomethyl). Examples of the aromatic diamine include p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfide, and 1,5-diaminonaphthalene. , 2,2'-Dimethyl-4,4'-diaminobiphenyl, 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl, 2,7-diaminopurine , 4,4'-diaminodiphenyl ether, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 9,9-bis(4-aminophenyl)anthracene, 2, 2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis(4-aminophenyl)hexafluoropropane, 4,4'-(p-phenylene diiso) Propyl)diphenylamine, 4,4'-(m-phenylenediisopropylidene)diphenylamine, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-amino Phenoxy)biphenyl, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminoacridine, 3,6-diaminocarbazole, N - 3-,6-diaminocarbazole, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, N,N'-bis(4-aminobenzene Benzylamine, N,N'-bis(4-aminophenyl)-N,N'-dimethylbenzidine, etc.; diaminoorganooxazane, for example, 1,3-bis(3-amino) For example, a diamine described in Patent Document 8 (Japanese Patent Laid-Open Publication No. 2010-97188) can be used.

The diamine used to synthesize the above polyamic acid is preferably a total relative to the diamine. The amount of the compound represented by the above formula (A-1) in an amount of 10 mol% or more is more preferably 30 mol% or more, and particularly preferably 50 mol% or more.

The ratio of the tetracarboxylic dianhydride and the diamine used in the synthesis of the polyamic acid is preferably 1 equivalent of the amino group contained in the diamine, and the acid anhydride group of the tetracarboxylic dianhydride is 0.2 equivalent to 2 The ratio of the equivalent is more preferably set to 0.3 equivalent to 1.2 equivalents.

The synthesis reaction of polylysine is preferably carried out in an organic solvent. Examples of the organic solvent include N-methyl-2-pyrrolidone, N,N-dimethylacetamide, and N,N-dimethylene. N,N-dimethyl formamide, dimethylsulfoxide, γ-butyrolactone, tetramethylurea, hexamethylphosphortriamide a non-protic polar solvent; phenolic derivatives such as m-cresol, xylenol, phenol halide; acetone, methyl ethyl ketone, methyl isobutyl ketone, Ketones such as cyclohexanone; ethyl lactate, butyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, diethyl oxalate, C Ethyl diacid, isoamyl propionate, isoamyl isobutyrate, etc.; diisoamyl ether, ethylene glycol methyl ether, ethylene glycol ether, ethylene glycol-n-propyl ether, ethylene glycol-different Propyl ether, ethylene glycol-n-butyl ether, ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, two Ethylene glycol monoethyl ether, diethylene glycol Ether acetate, diethylene glycol monoethyl ether acetate, Ethers such as tetrahydrofuran; halogenated hydrocarbons such as dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, o-dichlorobenzene; hydrocarbons such as benzene, toluene and xylene Or the like; one or more selected from the group consisting of these solvents can be used.

The reaction temperature of the synthesis reaction of poly-proline is preferably set to -20 ° C to 150 ° C, and more preferably set to 0 ° C to 100 ° C. The reaction time is preferably from 0.5 to 24 hours, more preferably from 2 to 12 hours.

The quinone imidized polymer of polyglycine which is a specific polymer of the present invention can be synthesized by subjecting polylysine synthesized in the above manner to dehydration ring closure. In this case, a complete quinone imine compound obtained by dehydrating and ring-closing all of the lysine structure of the polyamic acid may be prepared, or only a part of the valeric acid structure may be dehydrated and closed to form a proline. A partial quinone imide that has a structure and a quinone ring structure.

The dehydration ring closure of polylysine is preferably carried out by heating polylysine or by dissolving polylysine in an organic solvent, adding a dehydrating agent and a dehydration ring-closing catalyst to the solution, and heating as needed. The way to proceed. One of the best is to use the latter method.

In the above method of adding a dehydrating agent and a dehydration ring-closure catalyst to a solution of polyamic acid, for example, an acid anhydride such as acetic anhydride, propionic anhydride or trifluoroacetic anhydride can be used as the dehydrating agent. The use ratio of the dehydrating agent is preferably from 0.01 mol to 20 mol with respect to 1 mol of the proline structure of the polyglycolic acid. For the dehydration ring-closing catalyst, for example, pyridine, collidine, lutidine, triethylamine can be used. A tertiary amine. The use ratio of the dehydration ring-closure catalyst is preferably from 0.01 mol to 10 mol with respect to 1 mol of the dehydrating agent to be used. As the organic solvent used in the dehydration ring closure reaction, the organic solvent exemplified above can be used as a solvent for synthesizing polyamic acid.

The reaction temperature of the dehydration ring closure reaction is preferably from 0 ° C to 180 ° C, more preferably from 10 ° C to 150 ° C. The reaction time is preferably from 1.0 to 120 hours, more preferably from 2.0 to 30 hours.

The polyaminic acid or the quinone imidized polymer obtained in the above manner is preferably 20 mPa when it is made into a solution having a concentration of 10% by weight. s~800 mPa. The solution viscosity of the polymer of s, more preferably 30 mPa. s~500 mPa. s solution viscosity of the polymer. The solution viscosity (mPa.s) of the polymer is a polymer solution having a concentration of 10% by weight prepared using a good solvent (for example, γ-butyrolactone, N-methyl-2-pyrrolidone, etc.) of these polymers. The value obtained by measuring at 25 ° C using an E-type rotational viscometer.

The polystyrene-reduced molecular weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) is preferably 1,000 to 500,000, more preferably the polyperuric acid and the quinone imidized polymer thereof. It is 2,000~300,000. The ratio (Mw/Mn) of the Mw to the polystyrene-equivalent number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is preferably 15 or less, more preferably 10 or less. By being in the above molecular weight range, the stability of the liquid crystal alignment agent can be improved, and the good alignment property of the obtained liquid crystal display element can be ensured.

<Other ingredients>

The liquid crystal alignment agent of the present invention contains a specific polymer as described above as an essential component, and may contain other components as necessary. Examples of the other component include a polymer other than the specific polymer, a compound having at least one epoxy group in the molecule (hereinafter also referred to as "epoxy compound"), a functional decane compound, and the like.

[Other polymers]

The other polymers described above can be used to improve solution properties as well as electrical properties. The other polymer is a polymer having no structure represented by the above formula (A), and may be, for example, a quinone imidized polymer selected from the group consisting of polylysine, polylysine, polyphthalate, polyester. , polyamines, polyoxyalkylenes, cellulose derivatives, polyacetals, polystyrene and its derivatives, poly(styrene-phenylmethyleneimine) and its derivatives and poly(A) One or more of the group consisting of acrylates and a polymer having no structure represented by the above formula (I).

The ratio of use of the other polymer is preferably 50% by weight or less, more preferably 40% by weight or less, based on the total of the polymers (referred to as the total of the specific polymer and other polymers, the same applies hereinafter), and particularly It is preferably set to 30% by weight or less.

[epoxy compound]

Examples of the epoxy compound include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, and neopentyl glycol. Glycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, trimethylolpropane triglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, N, N , N', N'-tetraglycidyl - between Xylylenediamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N',N'-tetraglycidyl-4,4'-diamino Phenylmethane, N,N-diglycidyl-benzylamine, N,N-diglycidyl-aminomethylcyclohexane, N,N-diglycidyl-cyclohexylamine, etc. One or more of these compounds.

The epoxy compound is preferably used in an amount of 40 parts by weight or less, more preferably 0.1 parts by weight to 30 parts by weight, based on 100 parts by total of the total of the polymer.

[functional decane compound]

Examples of the above functional decane compound include 3-aminopropyltrimethoxydecane, 3-aminopropyltriethoxydecane, 2-aminopropyltrimethoxydecane, and 2-aminopropyltriethoxydecane. , N-(2-aminoethyl)-3-aminopropyltrimethoxydecane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxydecane, 3-ureidopropyl Trimethoxydecane, 3-ureidopropyltriethoxydecane, N-ethoxycarbonyl-3-aminopropyltrimethoxydecane, N-ethoxycarbonyl-3-aminopropyltriethoxy Decane, N-triethoxydecylpropyltriethylamine, N-trimethoxydecylpropyltriethylamine, 10-trimethoxydecyl-1,4,7-tri Azadecane, 10-triethoxydecyl-1,4,7-triazadecane, 9-trimethoxydecyl-3,6-diazaindolyl acetate, 9-trimethyl Oxyalkylalkyl-3,6-diazadecyl acetate, 9-triethoxydecyl-3,6-diazadecyl acetate, 9-trimethoxydecyl-3 Methyl 6-diazepine, methyl 9-triethoxydecyl-3,6-diazepine, N-benzyl-3-aminopropyltrimethoxydecane, N-benzyl -3- Aminopropyltriethoxydecane, N-phenyl-3-aminopropyltrimethoxydecane, N-phenyl-3-aminopropyltriethoxydecane, glycidoxymethyltrimethoxydecane , glycidoxymethyl triethoxy decane, 2-glycidol Oxyethyl trimethoxy decane, 2-glycidoxyethyl triethoxy decane, 3-glycidoxy propyl trimethoxy decane, 3-glycidoxy propyl triethoxy decane, etc. One or more selected from these compounds can be used.

The ratio of use of these functional decane compounds is preferably 2 parts by weight or less, more preferably 0.02 parts by weight to 0.2 parts by weight, based on 100 parts by weight of the total of the polymer.

<Preparation of Liquid Crystal Aligning Agent>

The liquid crystal alignment agent of the present invention is preferably a solution-like composition obtained by dissolving the above-mentioned specific polymer and other components arbitrarily used as needed, in an organic solvent.

The organic solvent used in the liquid crystal alignment agent of the present invention may, for example, be N-methyl-2-pyrrolidone, γ-butyrolactone, γ-butylide, N,N-dimethylformamide, N. , N-dimethylacetamide, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethoxylate Ethyl propionate, ethylene glycol methyl ether, ethylene glycol ether, ethylene glycol-n-propyl ether, ethylene glycol-isopropyl ether, ethylene glycol-n-butyl ether (butyl cellosolve), ethylene glycol Ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate , diethylene glycol monoethyl ether acetate, diisobutyl ketone, isoamyl propionate, isoamyl isobutyrate, diisoamyl ether, ethylene carbonate, propylene carbonate, etc., may be selected from One or more of these compounds.

The solid content concentration in the liquid crystal alignment agent of the present invention (the ratio of the total weight of components other than the solvent in the liquid crystal alignment agent to the total weight of the liquid crystal alignment agent) The examples are appropriately selected in consideration of viscosity, volatility, etc., and are preferably in the range of 1% by weight to 10% by weight. By setting the solid content concentration in this range, it is possible to form a liquid crystal alignment film having an appropriate film thickness with good coating properties, which is preferable.

The range of the particularly preferable solid content concentration differs depending on the method used when the liquid crystal alignment agent is coated on the substrate. For example, in the case of using a spinner method, it is particularly preferable to set the solid content concentration to a range of 1.5% by weight to 4.5% by weight. In the case of using the printing method, it is particularly preferable to set the solid content concentration to a range of 3% by weight to 9% by weight. In the case of using the inkjet method, it is particularly preferable to set the solid content concentration to a range of 1% by weight to 5% by weight.

The temperature at which the liquid crystal alignment agent of the present invention is prepared is preferably from 10 ° C to 50 ° C, more preferably from 20 ° C to 30 ° C.

<Method of Forming Liquid Crystal Alignment Film>

The liquid crystal alignment film can be formed by using, for example, the following steps using the liquid crystal alignment agent of the present invention.

(1) a step of applying a liquid crystal alignment agent of the present invention to form a coating film on a substrate (coating step); and (2) a step of irradiating the coating film with light (light irradiation step).

(3) Coating step

In the case where the liquid crystal alignment agent of the present invention is applied to a liquid crystal display element having a liquid crystal cell of a vertical electric field type, two substrates provided with a patterned transparent conductive film are used as a pair, and each of the transparent conductive films is provided. The liquid crystal alignment agent of the present invention is applied onto the formed surface to form a coating film. On the other hand, in the liquid crystal of the present invention In the case where the agent is applied to a liquid crystal display element having an FFS type liquid crystal cell of a transverse electric field type, a substrate having a pair of electrodes patterned with a transparent conductive film or a metal film on one side and a pair of electrodes having a comb shape is provided, and an electrode is not provided The counter substrate is used as a pair, and the liquid crystal alignment agent of the present invention is applied to each of the surface on which the comb-shaped electrode is formed and the one surface of the counter substrate to form a coating film.

In any of the above cases, for example, glass such as float glass or soda glass may be used for the substrate; and polyethylene terephthalate, polybutylene terephthalate, and polyether may be used. A transparent substrate such as tantalum or polycarbonate. As the transparent conductive film, for example, an ITO film containing In ₂ O ₃ —SnO ₂ , a NESA (registered trademark) film containing SnO ₂ , or the like can be used. As the metal film, for example, a film containing a metal such as chromium can be used. In the patterning of the transparent conductive film and the metal film, for example, a method of forming a pattern by a photolithography method, a sputtering method, or the like after forming a transparent conductive film having no pattern can be used, and a method of forming a transparent conductive film is required. The method of masking the pattern, etc.

When the liquid crystal alignment agent is applied to the substrate, in order to improve the adhesion between the substrate and the electrode and the coating film, a functional decane compound, titanate or the like may be applied to the substrate and the electrode before being heated. deal with.

When the coating of the liquid crystal alignment agent on the substrate is preferably an offset printing method, a spin coating method, a roll coater method, or an inkjet printing method ( Ink jet printing method) is carried out by an appropriate coating method. The liquid crystal matching of the present invention is applied in terms of maximizing the advantages of the present invention in which the in-plane uniformity of the coating film is extremely high. Inkjet printing is preferred for the agent. After coating, the coated surface is subjected to preliminary heating (prebaking), followed by calcination (post-baking), whereby a coating film can be formed. The prebaking conditions are, for example, a heating time of from 0.1 to 5 minutes at a heating temperature of from 40 ° C to 120 ° C, and the post-baking conditions are, for example, from 120 ° C to 300 ° C, preferably from 150 ° C to 250 ° C. The heating time is, for example, a heating time of 5 minutes to 200 minutes, preferably 10 minutes to 100 minutes. The film thickness of the coating film after post-baking is preferably 0.001 μm to 1 μm, more preferably 0.005 μm to 0.5 μm.

(4) Light irradiation step

Then, the coating film formed as described above is irradiated with the polarized light, whereby the liquid crystal alignment ability can be imparted to the coating film to form a liquid crystal alignment film.

As the light to be irradiated here, for example, ultraviolet rays, visible rays, or the like containing light having a wavelength of 150 nm to 800 nm can be used. It is preferably an ultraviolet ray containing light having a wavelength of from 200 nm to 400 nm. As the light source to be used, for example, a low pressure mercury lamp, a high pressure mercury lamp, a xenon lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, an Hg-Xe lamp, an excimer laser or the like can be used. The ultraviolet light in the above preferred wavelength region can be obtained by a method in which the above-described light source is used in combination with, for example, a filter, a diffraction grating, or the like.

When the radiation used for light irradiation is polarized light (linearly polarized or partially polarized), the surface of the coating film may be irradiated from the vertical direction, or may be irradiated from the oblique direction in order to impart a pretilt angle. On the other hand, in the case of irradiating non-polarized radiation, it is necessary to irradiate the coating film surface from the oblique direction.

The irradiation amount of light is preferably 1 J/m ² or more and less than 10,000 J/m ² , more preferably 10 J/m ² to 3,000 J/m ² . In addition, when a liquid crystal alignment ability is imparted to a coating film formed of a previously known liquid crystal alignment agent by a photo-alignment method, a radiation irradiation amount of 10,000 J/m ² or more is required. However, when the liquid crystal alignment agent of the present invention is used, the radiation irradiation amount in the case of the photo-alignment method is 5,000 J/m ² or less, further 3,000 J/m ² or less, and further 1,000 J/m ² or less. The liquid crystal alignment capability helps to reduce the manufacturing cost of liquid crystal display elements.

The liquid crystal alignment film formed in the above manner can obtain liquid crystal alignment ability with less light irradiation amount than in the prior art, and thus contributes to reduction in manufacturing cost of the liquid crystal display element.

<Liquid crystal display element>

The liquid crystal display element can be manufactured in the following manner using the substrate having the liquid crystal alignment film formed in the above manner.

A pair of substrates in which the liquid crystal alignment film is formed as described above is prepared, and a liquid crystal cell having a liquid crystal sandwiched between the pair of substrates is manufactured. In order to manufacture a liquid crystal cell, the following two methods are mentioned, for example.

In the first method, a pair of substrates are opposed to each other via a gap (cell gap) so that the liquid crystal alignment films face each other, and the peripheral portions of the pair of substrates are bonded together by a sealant on the surface of the substrate. And filling the liquid crystal into the cell gap divided by the sealant, and then sealing the injection hole, thereby manufacturing the liquid crystal cell.

In the second method, a predetermined portion of one of the two substrates on which the liquid crystal alignment film is formed is coated with, for example, an ultraviolet curable sealing material, and a predetermined number on the liquid crystal alignment film surface. After dropping the liquid crystal at one portion, the other substrate is bonded in a manner opposite to the liquid crystal alignment film, and the liquid crystal is dispersed. On the substrate surface, ultraviolet light is then applied to the entire surface of the substrate to harden the sealant, thereby manufacturing a liquid crystal cell. This second method is a method called the One Drop Fill (ODF) method.

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

Then, the liquid crystal display element of the present invention can be obtained by bonding a polarizing plate to the outer surface of the liquid crystal cell. Here, it is possible to obtain a desired liquid crystal display element by appropriately adjusting the angle formed by the polarization direction of the linearly polarized light irradiated to the pair of substrates on which the liquid crystal alignment film is formed and the angle between each of the substrates and the polarizing plate.

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

For the liquid crystal, for example, a nematic liquid crystal, a smectic liquid crystal, or the like can be used.

In the case of producing a TN type liquid crystal cell or an STN type liquid crystal cell, a nematic liquid crystal having positive dielectric anisotropy is preferably used, for example, a biphenyl liquid crystal, a phenylcyclohexane liquid crystal, or an ester liquid crystal is used. And a triphenylene liquid crystal, a biphenyl cyclohexane liquid crystal, a pyrimidine liquid crystal, a dioxane liquid crystal, a bicyclooctane liquid crystal, a cubane liquid crystal, or the like. Further, a liquid crystal may be further added to the liquid crystal: for example, cholesteric chloride, cholesteryl nonanoate, cholesteryl carbonate, or the like, cholesteric liquid crystal (cholesteric) Liquid crystal); chiral agent sold as trade name "C-15", "CB-15" (manufactured by Merck) Agent); ferroelectric liquid crystal such as p-decyloxybenzylidene-p-amino-2-methylbutylcinnamate.

On the other hand, in the case of producing a vertical alignment type liquid crystal cell, a nematic liquid crystal having a negative dielectric anisotropy is preferably used, and for example, a dicyanobenzene liquid crystal, a pyridazine liquid crystal, or the like can be used. The Schiff base is a liquid crystal, an azoxy liquid crystal, a biphenyl liquid crystal, a phenylcyclohexane liquid crystal or the like.

The polarizing plate used for the outer side of the liquid crystal cell is a polarizing plate in which a polarizing film called "H film" which absorbs iodine is sandwiched by a cellulose acetate protective film while extending the polyvinyl alcohol, or contains a H. The film itself is a polarizing plate or the like.

[Examples]

Hereinafter, the present invention will be specifically described by way of examples, but the invention is not limited to the examples.

In the following synthesis examples, the following synthesis examples and the necessary amounts of products used in the examples were ensured by repeating the operation in the following synthesis scheme as needed.

<Synthesis of a compound represented by the above formula (A-1)>

The following synthesis reactions were carried out under an inert gas atmosphere.

Synthesis Example A1-1

The compound (a-1) was synthesized according to the following scheme.

In a 500 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen introduction tube, 23.9 g of 4-bromophenylcyclohexane, 0.22 g of palladium acetate, 1.22 g of tris(o-tolyl)phosphine, and 56 mL of triethylamine were added. 8.2 mL of acrylic acid and 200 mL of N,N-dimethylacetamide were heated and stirred at 120 ° C for 3 hours to carry out a reaction. After completion of the reaction, the filtrate obtained by filtering the reaction mixture was mixed with 500 mL of ethyl acetate, washed twice with dilute hydrochloric acid and three times with water, and the solvent was removed under reduced pressure. The obtained solid was recrystallized from ethanol, whereby Compound (a-1-1) 17.0 g was obtained. In a 100 mL one-necked flask equipped with a reflux tube and a nitrogen introduction tube, 11.5 g of the above-obtained compound (a-1-1), 20 mL of thionyl chloride, and 0.1 mL of dimethylformamide were mixed. The reaction was carried out by heating and stirring at 80 ° C for 1 hour. After completion of the reaction, the reaction mixture was subjected to removal of unreacted sulfinium chloride under reduced pressure, and then mixed with 50 mL of tetrahydrofuran to obtain a solution (1).

On the other hand, in another container, diethylene glycol 48 mL, tetrahydrofuran 50 mL of cumane and 10.4 mL of triethylamine were stirred at 0 °C. After the solution (1) obtained above was dropped for 1 hour, the mixture was stirred at 20 ° C for 3 hours to carry out a reaction. After completion of the reaction, the reaction mixture was mixed with 300 mL of ethyl acetate, washed twice with dilute hydrochloric acid and three times with water. Then, the solvent was removed under reduced pressure, whereby Compound (a-1-2) 14.5 g was obtained.

In a 200 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen introduction tube, the above-obtained compound (a-1-2) 12.7 g, 2,4-dinitrofluorobenzene 7.8 g, and triethylamine 12 mL were mixed. 60 mL of tetrahydrofuran was stirred and heated at 40 ° C for 8 hours to carry out a reaction. After completion of the reaction, 300 mL of ethyl acetate was mixed in the reaction mixture, and the mixture was washed 4 times with water. Then, the solvent was removed under reduced pressure, whereby Compound (a-1-3) 18.0 g was obtained.

In a 1,000 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen introduction tube, 18.0 g of the compound (a-1-3) obtained above, 48.7 g of zinc powder, 8.0 g of ammonium chloride, 150 mL of ethanol, and tetrahydrofuran 150 were mixed. mL, stirred at 0 °C. In the mixture, 22 mL of distilled water was added dropwise over 1 hour, and the mixture was stirred at 20 ° C for 12 hours to carry out a reaction. After completion of the reaction, the filtrate obtained by filtration of the reaction mixture was mixed with ethyl acetate (400 mL) and washed with water four times. The solvent was removed under reduced pressure, and the obtained solid was recrystallized from ethanol, whereby 8.5 g of the diamine compound (a-1) was obtained.

Synthesis Example A1-2

Compound (a-2) was synthesized according to the following scheme.

[化25]

In a 500 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen introduction tube, 24.9 g of 4-bromodiphenyl ether, 0.22 g of palladium acetate, 1.22 g of tris(o-tolyl)phosphine, and 56 mL of triethylamine were added. 8.2 mL of acrylic acid and 200 mL of N,N-dimethylacetamide were heated and stirred at 120 ° C for 3 hours to carry out a reaction. After completion of the reaction, the filtrate obtained by filtering the reaction mixture was mixed with 500 mL of ethyl acetate, washed twice with dilute hydrochloric acid and three times with water, and the solvent was removed under reduced pressure. The obtained solid was recrystallized from ethanol, whereby 19.2 g of the compound (a-2-1) was obtained. In a 100 mL one-necked flask equipped with a reflux tube and a nitrogen introduction tube, 12.0 g of the obtained compound (a-2-1), 20 mL of sulfoxide, and 0.1 mL of dimethylformamide were mixed at 80 ° C. The reaction was carried out by heating and stirring for 1 hour. After completion of the reaction, the reaction mixture was subjected to removal of unreacted sulfinium chloride under reduced pressure, and then mixed with 50 mL of tetrahydrofuran to obtain a solution (2).

In another container, mix 1,3-propanediol 36 mL, tetrahydrofuran 50 mL And 10.4 mL of triethylamine was stirred at 0 °C. After the dropwise addition of the solution (2) obtained above for 1 hour, the mixture was stirred at 20 ° C for 3 hours to carry out a reaction. After completion of the reaction, the reaction mixture was mixed with 300 mL of ethyl acetate, washed twice with dilute hydrochloric acid and three times with water. The solvent was removed under reduced pressure, whereby Compound (a-2-2) 13.5 g was obtained.

In a 200 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen introduction tube, the above-obtained compound (a-2-2) 11.9 g, 2,4-dinitrofluorobenzene 7.8 g, and triethylamine 12 mL were mixed. 60 mL of tetrahydrofuran was stirred and heated at 40 ° C for 8 hours to carry out a reaction. After completion of the reaction, the reaction mixture was mixed with 300 mL of ethyl acetate and washed 4 times with water. The solvent was removed under reduced pressure to give Compound (a-2-3) 16.6 g.

In a 1,000 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen introduction tube, 16.6 g of the compound (a-2-3) obtained above, 46.7 g of zinc powder, 7.7 g of ammonium chloride, 140 mL of ethanol, and tetrahydrofuran 140 were mixed. mL, stirred at 0 °C. In the mixture, 21 mL of distilled water was added dropwise over 1 hour, and the mixture was stirred at 20 ° C for 12 hours to carry out a reaction. After completion of the reaction, the filtrate obtained by filtration of the reaction mixture was mixed with ethyl acetate (400 mL) and washed with water four times. The solvent was removed under reduced pressure, and the obtained solid was recrystallized from ethanol, whereby 5.8 g of the diamine compound (a-2) was obtained.

Synthesis Example A1-3

The compound (a-3) was synthesized according to the following scheme.

[Chem. 26]

In a 500 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen introduction tube, 20.1 g of 4-bromobenzoic acid, 0.22 g of palladium acetate, 1.22 g of tris(o-tolyl)phosphine, 56 mL of triethylamine, and 8.2 of acrylic acid were added. The reaction was carried out by stirring 200 mL of mL and N,N-dimethylacetamide at 120 ° C for 3 hours. After completion of the reaction, the filtrate obtained by filtering the reaction mixture was mixed with 500 mL of ethyl acetate, washed twice with dilute hydrochloric acid and three times with water, and the solvent was removed under reduced pressure. The obtained solid was recrystallized from ethanol, whereby 13.4 g of the compound (a-3-1) was obtained.

In a 500 mL three-necked flask equipped with a thermometer and a nitrogen introduction tube, 67 mL of triethylene glycol, 1.2 g of dimethylaminopyridine, and 1-(3-dimethylaminopropyl)-3-ethylcarbamate were mixed. The hydrazine imine hydrochloride 11.5 g and tetrahydrofuran 200 mL were stirred at 0 °C. In this, a mixed solution containing 10.3 g of the compound (a-3-1) obtained above and 100 mL of tetrahydrofuran was added dropwise for 1 hour, and the mixture was stirred at 20 ° C for 5 hours to carry out a reaction. After the reaction is completed, the reaction mixture is combined with ethyl acetate 500. Mix in mL and wash 4 times with water. The solvent was removed under reduced pressure, whereby Compound (a-3-2) 15.7 g was obtained.

The above-obtained compound (a-3-2) 13.5 g, 2,4-dinitrofluorobenzene 7.8 g, and triethylamine 12 mL were mixed in a 200 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen introduction tube. 60 mL of tetrahydrofuran was stirred and heated at 40 ° C for 8 hours to carry out a reaction. After completion of the reaction, 300 mL of ethyl acetate was mixed in the reaction mixture, and the mixture was washed 4 times with water. The solvent was removed under reduced pressure, whereby Compound (a-3-3) 18.4 g was obtained.

In a 1,000 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen introduction tube, 18.4 g of the compound (a-3-3) obtained above, 47.7 g of zinc powder, 7.8 g of ammonium chloride, 145 mL of ethanol, and tetrahydrofuran 145 were mixed. mL, stirred at 0 °C. In the mixture, 22 mL of distilled water was added dropwise over 1 hour, and the mixture was stirred at 20 ° C for 12 hours to carry out a reaction. After completion of the reaction, the filtrate obtained by filtration of the reaction mixture was mixed with ethyl acetate 450 mL, and washed with water four times. The solvent was removed under reduced pressure, and the obtained solid was recrystallized from ethanol, whereby 5.8 g of the diamine compound (a-3) was obtained.

Comparative Synthesis Example A1-4

The compound (a-4) was synthesized according to the following scheme.

[化27]

In a 100 mL one-necked flask equipped with a reflux tube and a nitrogen introduction tube, a compound (a-1-1) obtained in the same manner as in the above Synthesis Example A1-1, 11.5 g, sulfinium chloride 20 mL, and 0.1 mL of methylmethionine was stirred and heated at 80 ° C for 1 hour to carry out a reaction. After completion of the reaction, the reaction mixture was subjected to removal of unreacted sulfinium chloride under reduced pressure, and then mixed with 50 mL of tetrahydrofuran to obtain a solution (3).

In a separate vessel, 28 mL of ethylene glycol, 50 mL of tetrahydrofuran, and 10.4 mL of triethylamine were mixed and stirred at 0 °C. After the solution (3) obtained above was dropped for 1 hour, the mixture was stirred at 20 ° C for 3 hours to carry out a reaction. After completion of the reaction, the reaction mixture was mixed with 300 mL of ethyl acetate, washed twice with dilute hydrochloric acid and three times with water. The solvent was removed under reduced pressure, whereby Compound (a-4-1) 12.3 g was obtained.

The obtained compound (a-4-1) 11.0 g, 2,4-dinitrofluorobenzene 7.8 g, and triethylamine 12 mL were mixed in a 200 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen introduction tube. 60 mL of tetrahydrofuran was stirred and heated at 40 ° C for 8 hours to carry out a reaction. After completion of the reaction, the reaction mixture was mixed with 300 mL of ethyl acetate and washed 4 times with water. The solvent was removed under reduced pressure, and the obtained solid was obtained from ethanol. Recrystallization was carried out, whereby Compound (a-4-2) 11.6 g was obtained.

In a 1,000 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen introduction tube, the above obtained (a-4-2) 11.6 g, zinc powder 37.4 g, ammonium chloride 6.1 g, ethanol 115 mL, and tetrahydrofuran 115 mL were mixed. Stir at 0 °C. Among them, 17 mL of distilled water was dropped over 1 hour, and the mixture was stirred at 20 ° C for 12 hours to carry out a reaction. After completion of the reaction, the filtrate obtained by filtration of the reaction mixture was mixed with ethyl acetate (400 mL) and washed with water four times. The solvent was removed under reduced pressure, and the obtained solid was recrystallized from ethanol, whereby 7.4 g of the diamine compound (a-4) was obtained.

Comparative Synthesis Example A1-5

The compound (a-5) was synthesized according to the following scheme.

In a 100 mL one-necked flask equipped with a reflux tube and a nitrogen introduction tube, 7.4 g of trans-cinnamic acid, 20 mL of sulfoxide, and 0.1 mL of dimethylformamide were mixed, and the mixture was heated and stirred at 80 ° C for 1 hour. Carry out the reaction. After the reaction is completed, the reaction mixture is placed under reduced pressure to remove unreacted sulfinium chloride, and tetrahydrofuran. 50 mL was mixed and used as a solution (4).

In a separate vessel, 11.1 g of 2-(2,4-dinitrophenyl)ethanol, 100 mL of tetrahydrofuran, and 10.4 mL of triethylamine were mixed and stirred at 0 °C. After the solution (4) obtained above was dropped for 1 hour, the mixture was stirred at 20 ° C for 6 hours to carry out a reaction. After completion of the reaction, the reaction mixture was mixed with 300 mL of ethyl acetate, washed twice with dilute hydrochloric acid and three times with water. The solvent was removed under reduced pressure, and the obtained solid was recrystallized from ethanol, whereby compound (a-5-1) 14.5 g was obtained.

In a 1,000 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen introduction tube, 14.5 g of the compound (a-5-1) obtained above, 55.5 g of zinc powder, 9.1 g of ammonium chloride, 170 mL of ethanol, and tetrahydrofuran 170 were mixed. mL, stirred at 0 °C. After the dropwise addition of 25 mL of distilled water for 1 hour, the mixture was stirred at 20 ° C for 12 hours to carry out a reaction. After completion of the reaction, the filtrate obtained by filtration of the reaction mixture was mixed with ethyl acetate 600 mL, and washed with water four times. The solvent was removed under reduced pressure, and the obtained solid was recrystallized from ethanol, whereby 8.5 g of the diamine compound (a-5) was obtained.

<Synthesis of a specific polymer (polyproline)

Synthesis Example PA-1

4,10-Dioxatricyclo[6.3.1.0 ^2,7 ]dodecane-3,5,9,11-tetraketone as a tetracarboxylic dianhydride 2.24 g (0.01 mol) and as a diamine 4.25 g (0.01 mol) of the compound (a-1) obtained in the above Synthesis Example A1-1 was dissolved in 36.8 g of N-methyl-2-pyrrolidone, and reacted at 60 ° C for 4 hours, thereby obtaining a poly-containing polymer. A solution of 15% by weight of proline (PA-1) was 42.0 g. The solution viscosity of the polyamic acid solution is 350 mPa. s.

Synthesis Example PA-2

1,6 g (0.01 mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as a tetracarboxylic dianhydride, and a compound (a-2) obtained in the above Synthesis Example A1-2 as a diamine 4.04 g (0.01 mol) was dissolved in 34.0 g of N-methyl-2-pyrrolidone and reacted at 40 ° C for 4 hours, thereby obtaining a solution containing 15% by weight of polyglycine (PA-2) 39.0 g. . The solution viscosity of the polyaminic acid solution is 400 mPa. s.

Synthesis Example PA-3

4,10-dioxatricyclo[6.3.1.0 ^2,7 ]dodecane-3,5,9,11-tetraone 2.02 g (0.009 mol) and 1,2 as tetracarboxylic dianhydride 0.25 g (0.001 mol) of 3,5-benzenetetracarboxylic dianhydride, and 4.25 g (0.01 mol) of the compound (a-1) obtained in the above Synthesis Example A1-1 as a diamine were dissolved in N- In 36.8 g of methyl-2-pyrrolidone, the reaction was carried out at 60 ° C for 4 hours, whereby 42.0 g of a solution containing 15% by weight of polyglycine (PA-3) was obtained. The solution viscosity of the polyaminic acid solution is 380 mPa. s.

Synthesis Example PA-4

1.6 g (0.009 mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as tetracarboxylic dianhydride and 0.22 g of 1,2,3,5-benzenetetracarboxylic dianhydride (0.001) Mole), and 4.04 g (0.01 mol) of the compound (a-2) obtained in the above Synthesis Example A1-2 as a diamine were dissolved in N-methyl-2-pyrrolidone 34.1 g, and reacted at 40 ° C. 4 hours, 39.0 g of a solution containing 15% by weight of polyamidamine (PA-4) was thus obtained. The solution viscosity of the polyaminic acid solution is 390 mPa. s.

Synthesis Example PA-5

4,10-Dioxatricyclo[6.3.1.0 ^2,7 ]dodecane-3,5,9,11-tetraketone as a tetracarboxylic dianhydride 2.24 g (0.01 mol) and as a diamine 4.44 g (0.10 mol) of the compound (a-3) obtained in the above Synthesis Example A1-3 was dissolved in 37.9 g of N-methyl-2-pyrrolidone, and reacted at 60 ° C for 4 hours, thereby obtaining a poly-containing polymer. A solution of 15% by weight of proline (PA-5) was 43.5 g. The solution viscosity of the polyaminic acid solution is 420 mPa. s.

<Synthesis of other polymers (polyproline)

Synthesis Example PA-6

1,6 g of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as tetracarboxylic dianhydride and 2,2'-dimethyl-4,4'-diaminobiphenyl 2.12 as diamine g (0.01 mol) was dissolved in 23.1 g of N-methyl-2-pyrrolidone, and reacted at 40 ° C for 4 hours, thereby obtaining 26.0 g of a solution containing 15% by weight of polyglycine (PA-6). The solution viscosity of the polyaminic acid solution is 400 mPa. s.

Synthesis Example PA-7

4,10-Dioxatricyclo[6.3.1.0 ^2,7 ]dodecane-3,5,9,11-tetraketone as a tetracarboxylic dianhydride 2.24 g (0.01 mol) and as a diamine 3.80 g (0.01 mol) of the compound (a-4) obtained in the above Comparative Synthesis Example A1-4 was dissolved in 30.1 g of N-methyl-2-pyrrolidone, and reacted at 60 ° C for 4 hours, thereby obtaining a content. A solution of 15% by weight of polyglycine (PA-7) was 35.2 g. The solution viscosity of the polyaminic acid solution is 380 mPa. s.

Synthesis Example PA-8

4,10-Dioxatricyclo[6.3.1.0 ^2,7 ]dodecane-3,5,9,11-tetraketone as a tetracarboxylic dianhydride 2.24 g (0.01 mol) and as a diamine 2.82 g (0.01 mol) of the compound (a-5) obtained in the above Synthesis Example A1-5 was dissolved in 28.7 g of N-methyl-2-pyrrolidone, and reacted at 60 ° C for 4 hours, thereby obtaining a poly-containing polymer. A solution of 15% by weight of proline (PA-8) was 32.8 g. The solution viscosity of the polyaminic acid solution is 400 mPa. s.

Example 1

<Preparation of Liquid Crystal Aligning Agent>

N-methylpyrrolidone and butyl cellosolve were added to a solution containing polylysine (PA-1) synthesized in the above Synthesis Example PA-1 as polylysine to prepare a solvent composition of N-methylpyrrolidone. /Blisten cellosolve = 50/50 (weight ratio), a solution having a solid concentration of 3.8% by weight. This solution was filtered through a screening procedure having a pore size of 1 μm to prepare a liquid crystal alignment agent (C-1).

<Evaluation of inkjet coating properties>

The liquid crystal alignment agent (C-1) prepared above was coated on a tantalum wafer using an inkjet coater (manufactured by Shibaura Mechatronics Co., Ltd.). The coating conditions at this time were as follows: 2 round trips (four times in total) were applied under conditions of 2,500 times/(nozzle.min) and a discharge amount of 200 mg/10 seconds. After coating, it was allowed to stand for 1 minute, and then heated at 80 ° C, thereby forming a coating film having an average film thickness of 0.1 μm. The obtained coating film was visually observed under irradiation with an interference fringe lamp (sodium lamp) to evaluate the surface uniformity of the coating film. In this case, the case where neither unevenness nor cissing was observed was evaluated as inkjet coating property ○ (good), and at least one of unevenness and cratering was evaluated as a spray. Ink coating property × (bad). Evaluation results are shown in Table 1. It is expressed as "IJ coating property".

<Manufacture of liquid crystal display element>

A glass substrate having a metal electrode including chromium which is patterned into a comb shape on one side and a counter glass substrate not provided with an electrode are used as a pair, and the surface of the glass substrate having the electrode and the surface facing the glass substrate are utilized. The rotator was separately applied to the liquid crystal alignment agent (C-1) prepared above, and prebaked on a hot plate at 80 ° C for 1 minute, and then heated at 200 ° C in an oven in which the inside of the library was replaced with nitrogen. (post-baking) For 1 hour, a coating film having a film thickness of 0.1 μm was formed.

Then, using Hg-Xe lamps and Glan-Taylor prisms on the surfaces of the coating films, polarized ultraviolet rays of 400 J/m ² including an open line of 313 nm were irradiated from the normal direction of the substrate to obtain A pair of substrates of a liquid crystal alignment film.

On the outer periphery of the surface of the one of the substrates having the liquid crystal alignment film, an epoxy resin adhesive having an alumina ball having a diameter of 5.5 μm is applied by screen printing to form a pair of substrates. The liquid crystal alignment film faces each other, and the pressure is projected so as to be parallel to the direction in which the optical axis of the polarized ultraviolet light is projected onto the substrate surface, and the adhesive is thermally cured by being dried at 150 ° C for 1 hour. Then, liquid crystal MLC-7028 manufactured by Merck was filled in the gap between the substrates from the liquid crystal injection port, and then the liquid crystal injection port was sealed with an epoxy-based adhesive. Further, in order to eliminate the flow alignment during liquid crystal injection, the film was heated at 150 ° C and then slowly cooled to room temperature. Then, the polarizing plates are bonded to each other on the outer surface of the substrate so as to be orthogonal to each other, and are bonded to the direction in which the optical axis of the polarized ultraviolet ray of the liquid crystal alignment film is incident on the substrate surface at 45°, thereby producing a liquid crystal display. element.

<Evaluation of Liquid Crystal Display Element>

(5) Evaluation of liquid crystal alignment

Observing the presence or absence of an abnormal region in the change in brightness and darkness when the liquid crystal display element manufactured as described above is turned on or off (applied or released) with a voltage of 5 V is observed by an optical microscope. The case of the abnormal region was evaluated as liquid crystal alignment property ○ (good), and the case where the abnormal region was observed was evaluated as liquid crystal alignment property × (bad). The evaluation results are shown in Table 1.

(6) Evaluation of voltage retention rate

The liquid crystal display element produced above was applied with a voltage of 5 V at an interval of 60 μsec and a space of 167 msec at 60 ° C, and then self-applied by VHR-1 manufactured by Toyo Technica. The voltage holding ratio after 167 milliseconds is released. The case where the voltage holding ratio was 99% or more was evaluated as a voltage holding ratio ◎ (extremely good), 95% or more and less than 99% was evaluated as ○ (good), and when less than 95% was evaluated as × (bad) ). The evaluation results are shown in Table 1 as "VHR".

Example 2 to Example 7 and Comparative Example 1 to Comparative Example 2

In the same manner as in the above Example 1, the liquid crystal alignment agent C-2 to the liquid crystal alignment agent C-7 and the liquid crystal were separately prepared except that the types and amounts of the polyamic acid to be used were respectively as described in Table 1. The alignment agent D-1 and the liquid crystal alignment agent D-2 were evaluated. The evaluation results are shown in Table 1, respectively.

Further, in Example 6 and Example 7, two kinds of polymers were used in combination when preparing a liquid crystal alignment agent.

Claims (7)

A liquid crystal alignment agent comprising a polymer having a structure represented by the following formula (A): In the formula (A), B is a group containing a cinnamic acid structure, a is an integer of 1 to 4, and b and c are each independently an integer of 0 to 8, wherein when a is 1, b+c≧3 When a is an integer of 2 to 4, b+c≧2, and "*" indicates a binding bond. The liquid crystal alignment agent according to the above aspect of the invention, wherein the group B in the formula (A) is a group represented by the following formula (B-1) or (B-2): R in the formula (B-1) is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, a phenyl group or a phenoxy group; In (B-2), R ¹ is an alkyl group having 1 to 10 carbon atoms, and R ² is an alkylene group having 2 to 10 carbon atoms, a divalent aromatic group having 6 to 18 carbon atoms, and a carbon number of 3 to 12; a divalent alicyclic group, a divalent fused ring group having a carbon number of 11 to 18 or a heterocyclic group having a ring number of 5 or 6, and Z ² and Z ³ are each independently a single bond, an oxygen atom, or -COO- Or -OCO-, e is an integer from 0 to 3; and "+" indicates a binding bond. The liquid crystal alignment agent according to the above aspect, wherein the polymer is selected from the group consisting of a reaction of a tetracarboxylic dianhydride with a diamine containing a compound represented by the following formula (A-1). At least one of the group consisting of polylysine and its ruthenium-imiding polymer: In the formula (A-1), B, a, b and c have the same meanings as B, a, b and c in the above formula (A), respectively. The liquid crystal alignment agent according to claim 3, wherein the tetracarboxylic dianhydride comprises at least one selected from the group consisting of 2,3,5-tricarboxycyclopentylacetic acid Anhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3, 4-cyclobutane tetracarboxylic dianhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-c]furan-1,3- Diketone, 1,3,3a,4,5,9b-hexahydro-8-methyl-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2- c] furan-1,3-dione, 3,5,6-tricarboxy-2-carboxymethylnorbornane-2; 3,5;6-dianhydride, 2,4,6,8-tetracarboxyl Bicyclo[3.3.0]octane-2; 4,6;8-dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride and pyromellitic dianhydride. A liquid crystal alignment film which is formed by the liquid crystal alignment agent according to any one of claims 1 to 4. A liquid crystal display element comprising the liquid crystal alignment film according to item 5 of the patent application. A polymer having the structure represented by the above formula (A) in the liquid crystal alignment agent according to the first aspect of the invention.