TWI461462B - A liquid crystal alignment agent and a liquid crystal display device using the liquid crystal display device - Google Patents

Description

Liquid crystal alignment treatment agent and liquid crystal display element using same

The present invention relates to a liquid crystal alignment treatment agent, a liquid crystal alignment film using the same, and a liquid crystal display element.

The liquid crystal display element has a structure in which the liquid crystal molecules are held by the liquid crystal alignment film formed on the substrate, and the liquid crystal molecules are aligned in a certain direction by the liquid crystal alignment film, and a display element that responds by voltage is used. The liquid crystal alignment film is generally a surface of a polyimide film formed on a substrate to which an electrode is attached, and is rubbed by applying pressure on the surface by a crucible or a nylon cloth to perform a so-called "friction treatment". Production. Since the alignment direction and the pretilt angle of the liquid crystal molecules are determined by the rubbing treatment, the rubbing treatment is a very important step, but the damage to the film surface or the peeling of the film by the rubbing treatment becomes a big problem. The flaw or peeling of the surface of the liquid crystal alignment film is an important cause of display failure when it is used as a liquid crystal display element.

As a means for forming a polyimide film on a substrate to which an electrode is attached, a method of forming a coating film using a solution of a polyimide precursor such as polylysine, and imidizing the substrate thereon is used in advance. A method of imidizing a solution of a soluble polyimine.

Among them, the method of containing a solution of a soluble polyimine can form a polyimide film having good properties as a liquid crystal alignment film even at a lower temperature, and conversely, the film formed has a low strength. It is easy to cause problems associated with the above rubbing treatment.

From the above, it has been found that the applicant of the present application has proposed that the solubility of polyimine in an organic solvent is improved, and that it is difficult to cause damage to the surface of the film or peeling of the film by rubbing treatment, and the use of a specific diamine component is obtained. The liquid phase alignment treatment agent of the imidized acid imidized soluble polyimine.

Further, as the size of the panel increases and the brightness increases, the decrease in the pretilt angle caused by the heat generated by the backlight becomes a problem. As a method of expressing the pretilt angle, it has been proposed to use a diamine having an alkyl side chain (for example, refer to Patent Document 2), a diamine having a steroid skeleton in a side chain (for example, refer to Patent Document 3), and a ring structure in a side chain. A diamine (for example, refer to Patent Document 4). When a diamine having an alkyl side chain is generally used, the liquid crystal alignment property is good, but the thermal stability of the pretilt angle is deteriorated, and the pretilt angle is lowered when the temperature is increased. On the other hand, a polyamic acid or a soluble polyimine having a steroid skeleton or a side chain having a ring structure of a diamine having a side chain is excellent in thermal stability of a pretilt angle, but liquid crystal alignment property and dissolution into an organic solvent. Sex has a tendency to decrease.

[Advanced technical literature]

[Patent Literature]

[Patent Document 1] International Publication No. 2006/126555

[Patent Document 2] Japanese Patent Publication No. 05-043687

[Patent Document 3] Japanese Patent Publication No. 04-281427

[Patent Document 4] Japanese Patent Publication No. 02-223916

In view of the above, the present invention has an object of providing a liquid crystal alignment treatment agent for forming a liquid crystal alignment film which satisfies the alignment property at the time of liquid crystal injection, the resistance to rubbing treatment, and the pretilt angle at a high temperature. That is, the present invention provides that it is difficult to cause damage to the surface of the liquid crystal alignment film or peeling of the liquid crystal alignment film by the rubbing treatment, and the liquid crystal alignment property at the time of liquid crystal injection is good, and the pretilt angle is also stable at a high temperature and is difficult to be lowered. The liquid crystal alignment agent of the liquid crystal alignment film is intended for the purpose.

The present inventors intend to achieve the above object and carry out detailed research results to complete the present invention. That is, the present invention has the following gist.

(1) A liquid crystal alignment treatment agent comprising at least one of a polyamic acid obtained by reacting a diamine component and a tetracarboxylic dianhydride component, and a soluble polyamidiene obtained by imidization. In the polymer, the diamine component contains a diamine represented by the formula [1] and a diamine represented by the formula [2].

(wherein n is an integer from 0 to 19.)

(2) The liquid crystal alignment treatment agent according to the above (1), wherein a content ratio of the tetracarboxylic dianhydride component to the diamine component is expressed by a molar ratio of 1:0.8 to 1:1.2.

(3) The liquid crystal alignment treatment agent according to the above (1) or (2), wherein the diamine component contains 20 mol% or more of the diamine represented by the formula [1].

(4) The liquid crystal alignment treatment agent according to any one of the above-mentioned (1), wherein the diamine component contains 5 to 60 mol% of the diamine represented by the formula [2].

(5) The liquid crystal alignment treatment agent according to any one of the above-mentioned (1), wherein the diamine represented by the formula [2] in the diamine component is one of the diamines represented by the formula [1]. In the case of Mohr, it is 0.1 mol to 1.2 mol.

(2) The liquid crystal alignment treatment agent according to any one of the above-mentioned (1), wherein the diamine of the formula [1] and the diamine of the formula [2] each have two amine groups. The positional relationship is a meta or alignment.

(7) The liquid crystal alignment treatment agent according to any one of the above aspects, wherein the tetracarboxylic dianhydride component contains a tetracarboxylic dianhydride having an alicyclic structure or an aliphatic structure.

(8) The liquid crystal alignment treatment agent according to any one of the above aspects, wherein the tetracarboxylic dianhydride component contains an aromatic tetracarboxylic dianhydride.

(9) A liquid crystal alignment film which is obtained by applying the liquid crystal alignment treatment agent according to any one of the above (1) to (8) to a substrate having an electrode, followed by firing and rubbing treatment. Got it.

(10) A liquid crystal display element comprising the liquid crystal display element of the liquid crystal alignment film according to (9) above.

[Effects of the Invention]

By using the liquid crystal alignment treatment agent of the present invention, a liquid crystal alignment film having good liquid crystal alignment property at the time of liquid crystal injection can be formed, and damage to the surface of the liquid crystal alignment film or peeling of the liquid crystal alignment film can be suppressed in the high temperature. Since the pretilt angle is hard to be lowered, a liquid crystal display element which exhibits less defects and has stability characteristics at a high temperature is displayed.

[Formation of the Invention]

The liquid crystal alignment treatment agent of the present invention is a polyamic acid obtained by reacting a diamine component and a tetracarboxylic dianhydride component, and/or a soluble polyamidiamine which is imidized by the polyaminic acid, the above two The amine component contains a diamine represented by the following formula [1] and formula [2]. Further, in the present invention, the soluble polyimine is a polyimine which is soluble in the organic solvent used in the liquid crystal alignment treatment agent of the present invention.

Where n is an integer from 0 to 19.

In the diamine represented by the formula [1], the position of each substituent on the benzene ring is not particularly limited, but the positional relationship of the two amine groups is preferably inter- or pairwise. Preferred specific examples of the diamine are listed below, but are not limited thereto.

In the present invention, the diamine component which is a raw material of polylysine or soluble polyimine may be only a diamine represented by the formula [1] and the formula [2], or may be selected in combination with other diamines. Kind or more than two. As a diamine component to obtain a polyaminic acid or a soluble polyimine, by containing a diamine represented by the formula [1], the problem of damage to the surface of the film or peeling of the film when the coating film is subjected to rubbing treatment can be improved. At the same time, the solubility of polyimine in organic solvents is also improved.

In the diamine component, the diamine represented by the formula [1] is such that the higher the content ratio, the higher the effect of suppressing the damage of the surface of the alignment film during the rubbing treatment or the peeling of the film, and the poly-proline or soluble polypeptone. The solubility of the imine in an organic solvent is also improved.

The content of the diamine represented by the formula [1] may be only 5 mol% or more of the total diamine component, and the effect of suppressing the damage of the surface of the alignment film or the peeling of the film at the time of rubbing treatment may be obtained, but if it is 20 mol When it is more than %, it is preferable to obtain sufficient resistance even in combination with a diamine which is weak in frictional cutting resistance. Further, the content of the diamine is preferably 95% by mole or less.

The diamine represented by the formula [2] is an essential component for exhibiting a good liquid crystal alignment property and a pretilt angle which is stable at a high temperature. The content of the diamine represented by the formula [2] in the diamine component is 0.1 to 1.2 mols, preferably 0.3 to 1.1 mols, more preferably 1 to 1.2 mols, more preferably 1 mol of the diamine represented by the formula [1]. 0.5 to 1.1 moles. When the content of the diamine represented by the formula [2] is small, the expected pretilt angle may not be exhibited, and conversely, if the content is large, the friction cutting may be deteriorated.

The content of the diamine represented by the formula [2] in the diamine component can be adjusted depending on the intended pretilt size, but is preferably from 1 to 90 mol%, more preferably from 5 to 60 mol%.

In the diamine represented by the formula [2], the position of each substituent on the benzene ring is not particularly limited, and the positional relationship of the two amine groups is preferably inter- or pairwise. Preferred specific examples of the diamine are listed below, but are not limited thereto.

Where n is an integer from 0 to 19. When n is small, the pretilt angle cannot be expressed, and when it is large, the solubility of the soluble polyimine is lowered. Preferably, the range of n is from 3 to 15, more preferably from 5 to 10.

In the above diamine component, the formulas [1] and [2] may be the only ones, but other diamines may be used in combination. The other diamines in this case are not particularly limited, but specific examples thereof are mentioned. The following amines are mentioned.

Examples of the alicyclic diamines include 1,4-diamine cyclohexane, 1,3-diamine cyclohexane, 4,4'-diamine dicyclohexylmethane, and 4,4'-. Diamine-3,3'-dimethyldicyclohexylamine, isophorone diamine, and the like.

Examples of the aromatic diamines include o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 2,4-diamine toluene, and 2,5-diamine. Toluene, 3,5-diamine toluene, 1,4-diamine-2-methoxybenzene, 2,5-diamine-p-xylene, 1,3-diamine-4-chlorobenzene, 3, 5-diamine benzoic acid, 1,4-diamine-2,5-dichlorobenzene, 4,4'-diamine-1,2-diphenylethane, 4,4'-diamine-2, 2'-Dimethylbiphenylmethyl, 4,4'-diaminediphenylmethane, 3,3'-diaminediphenylmethane, 3,4'-diaminediphenylmethane, 4,4 '-Diamine-3,3'-dimethyldiphenylmethane, 2,2'-diamine stilbene, 4,4'-diamine stilbene, 4,4'-diamine diphenyl Ether, 3,4'-diamine diphenyl ether, 4,4'-diamine diphenyl sulfide, 4,4'-diamine diphenyl hydrazine, 3,3'-diamine diphenyl hydrazine , 4,4'-diamine benzophenone, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-double (4-Aminophenoxy)benzene, 3,5-bis(4-aminophenoxy)benzoic acid, 4,4'-bis(4-aminophenoxy)biphenylmethyl, 2, 2-bis[(4-aminophenoxy)methyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl Hexafluoropropane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, bis[4-(3-aminophenoxy)phenyl]anthracene, bis[4-( 4-aminophenoxy)phenyl]anthracene, 1,1-bis(4-aminophenyl)cyclohexane, α,α'-bis(4-aminophenyl)-1,4-di Isopropylbenzene, 9,9-bis(4-aminophenyl)anthracene, 2,2-bis(3-aminophenyl)hexafluoropropane, 2,2-bis(4-aminophenyl) Hexafluoropropane, 4,4'-diamine diphenylamine, 2,4-diamine diphenylamine, 1,8-diamine naphthalene, 1,5-diamine naphthalene, 1,5-diamine oxime Bismuth, 1,3-diamine oxime, 1,6-diamine oxime, 1,8-diamine oxime, 2,7-diamine oxime, 1,3-bis(4-aminophenyl)tetramethyl Dioxane, benzidine, 2,2'-dimethylbenzidine, 1,2-bis(4-aminophenyl)ethane, 1,3-bis(4-aminophenyl)propane, 1,4-bis(4-aminophenyl)butane, 1,5-bis(4-aminophenyl)pentane, 1,6-bis(4-aminophenyl)hexane, 1, 7-bis(4-aminophenyl)heptane, 1,8-bis(4-aminophenyl)octane, 1,9-bis(4-aminophenyl)decane, 1,10- Bis(4-aminophenyl)decane, 1,3-bis(4-aminophenoxy)propane, 1,4-bis(4-aminophenoxy)butane, 1,5-double (4-aminophenoxy)pentane, 1,6-bis(4-aminobenzene Hexane, 1,7-bis(4-aminophenoxy)heptane, 1,8-bis(4-aminophenoxy)octane, 1,9-bis(4-aminobenzene Oxy) decane, 1,10-bis(4-aminophenoxy)decane, bis(4-aminophenyl)propane-1,3-diester, bis(4-aminophenyl) Butane-1,4-diester, bis(4-aminophenyl)pentane-1,5-diester, bis(4-aminophenyl)hexane-1,6-diester, di( 4-aminophenyl)heptane-1,7-diester, bis(4-aminophenyl)octane-1,8-diester, bis(4-aminophenyl)decane-1, 9-Diester, bis(4-aminophenyl)decane-1,10-diester, 1,3-bis[4-(4-aminophenoxy)phenoxy]propane, 1,4 - bis[4-(4-aminophenoxy)phenoxy]butane, 1,5-bis[4-(4-aminophenoxy)phenoxy]pentane, 1,6-double [4-(4-Aminophenoxy)phenoxy]hexane, 1,7-bis[4-(4-aminophenoxy)phenoxy]heptane, 1,8-bis[4 -(4-Aminophenoxy)phenoxy]octane, 1,9-bis[4-(4-aminophenoxy)phenoxy]decane, 1,10-bis[4-( 4-aminophenoxy)phenoxy]nonane and the like.

Examples of the aromatic-aliphatic diamine include 3-aminobenzylamine, 4-aminobenzylamine, 3-amino-N-methylbenzylamine, and 4-amine. Benzyl-N-methylbenzylamine, 3-aminophenethylamine, 4-aminophenethylamine, 3-amino-N-methylphenethylamine, 4-amino-N- Methylphenethylamine, 3-(3-aminopropyl)aniline, 4-(3-aminopropyl)aniline, 3-(3-methylaminopropyl)aniline, 4-(3- Methylaminopropyl)aniline, 3-(4-aminobutyl)aniline, 4-(4-aminobutyl)aniline, 3-(4-methylaminobutyl)aniline, 4-( 4-methylaminobutyl)aniline, 3-(5-aminopentyl)aniline, 4-(5-aminopentyl)aniline, 3-(5-methylaminopentyl)aniline, 4 -(5-methylaminopentyl)aniline, 2-(6-aminonaphthyl)methylamine, 3-(6-aminonaphthyl)methylamine, 2-(6-aminonaphthyl) Ethylamine, 3-(6-aminonaphthyl)ethylamine, and the like.

Examples of the heterocyclic diamines include 2,6-diaminepyridine, 2,4-diaminepyridine, 2,4-diamine-1,3,5-triazine, 2,7-di. Amine dibenzofuran, 3,6-diamine carbazole, 2,4-diamine-6-isopropyl-1,3,5-triazine, 2,5-bis(4-aminophenyl) -1,3,4-oxadiazole and the like.

Examples of the aliphatic diamines include 1,2-diamineethane, 1,3-diaminepropane, 1,4-diaminebutane, 1,5-diaminepentane, 1,6. -diamine hexane, 1,7-diamine heptane, 1,8-diamine octane, 1,9-diamine decane, 1,10-diamine decane, 1,3-diamine-2 , 2-dimethylpropane, 1,6-diamine-2,5-dimethylhexane, 1,7-diamine-2,5-dimethylheptane, 1,7-diamine-4 , 4-dimethylheptane, 1,7-diamine-3-methylheptane, 1,9-diamine-5-methylheptane, 1,12-diaminedodecane, 1,18 - Diamine octadecane, 1,2-bis(3-aminopropoxy)ethane, and the like.

Examples of the diamine having a long-chain alkyl group, a perfluoroalkyl group, an aromatic cyclic group, an aliphatic cyclic group, or a combination of the substituents and a steroid skeleton group include the following. Further, in the structures exemplified below, j represents an integer of 5 to 20, and k represents an integer of 1 to 20.

In the present invention, the tetracarboxylic dianhydride component as a raw material of polylysine or a soluble polyimine may be one type of tetracarboxylic dianhydride or may be a mixture of two or more kinds of tetracarboxylic dianhydride. use.

In the effect of improving the liquid crystal alignment property, the surface damage or peeling of the liquid crystal alignment film generated during the rubbing treatment, and the reduction of the pretilt angle at a high temperature, the tetracarboxylic dianhydride is not particularly limited.

However, from the viewpoint of increasing the voltage holding ratio of the liquid crystal cell, it is preferred to use a tetracarboxylic dianhydride having an alicyclic structure or an aliphatic structure. Examples of the tetracarboxylic dianhydride having an alicyclic structure or an aliphatic structure include 1,2,3,4-cyclobutanetetracarboxylic dianhydride and 1,2-dimethyl-1,2,3. , 4-cyclobutane tetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1 , 2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2,3,4-cyclopentane tetracarboxylic dianhydride, 2,3,4,5-tetrahydrofuran tetracarboxylic dianhydride, 1, 2,4,5-cyclohexanetetracarboxylic dianhydride, 3,4-dicarboxy-1-cyclohexyl succinic dianhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1 - naphthalene succinic dianhydride, 1,2,3,4-butane tetracarboxylic dianhydride, bicyclo[3,3,0]octane-2,4,6,8-tetracarboxylic dianhydride, 3, 3',4,4'-Dicyclohexyltetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, cis-3,7-dibutylcyclooctane-1,5-diene -1,2,5,6-tetracarboxylic dianhydride, tricyclo[4.2.1.0 ^2,5 ]decane-3,4,7,8-tetracarboxylic acid-3,4:7,8-dianhydride , six rings [6.6.0.1 ^2,7 .0 ^3,6 .1 ^9,14 .0 ^10,13 ] hexadecane-4,5,11,12-tetracarboxylic acid-4,5:11,12- Diacetic anhydride, 4-(2,5-di-oxo-tetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic anhydride, and the like.

Further, in the case of using a tetracarboxylic dianhydride having the above alicyclic structure or aliphatic structure, when an aromatic tetracarboxylic dianhydride is used, liquid crystal alignment property can be improved, and the cumulative charge of the liquid crystal cell can be reduced, which is preferable. Examples of the aromatic tetracarboxylic dianhydride include pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, and 2,2',3,3'-biphenyl. Tetracarboxylic dianhydride, 2,3,3',4-biphenyltetracarboxylic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 2,3,3 ',4-benzophenonetetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl)ether dianhydride, bis(3,4-dicarboxyphenyl)ruthenic anhydride, 1,2,5, 6-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, and the like.

Considering the balance of liquid crystal alignment, voltage holding ratio, and accumulated charge of polylysine or soluble polyimine, and using tetracarboxylic dianhydride having an alicyclic structure or an aliphatic structure, and aroma A group of tetracarboxylic dianhydrides is preferred. At this time, the molar ratio of the former/the latter is preferably 90/10 to 50/50, preferably 80/20 to 60/40.

The polyamic acid or the soluble polyimine used in the liquid crystal alignment treatment agent of the present invention is a polyamic acid obtained by reacting the above diamine component with a tetracarboxylic dianhydride component, or the imine Polyimine. Among them, the reaction of obtaining polyamic acid is such that the tetracarboxylic dianhydride component and the diamine component can be mixed in an organic solvent.

As a method of mixing a tetracarboxylic dianhydride component and a diamine component in an organic solvent, a solution in which a diamine component is dispersed or dissolved in an organic solvent is stirred, and a tetracarboxylic dianhydride component is directly dispersed or dispersed. Or a method of adding in an organic solvent, and conversely adding a diamine component to a solution in which a tetracarboxylic dianhydride component is dispersed or dissolved in an organic solvent, and a tetracarboxylic dianhydride component and a diamine component are mutually added. Method, etc. Further, when the tetracarboxylic dianhydride component or the diamine component is formed from a plurality of compounds, the plurality of compounds may be subjected to a polycondensation reaction in a state of being mixed in advance, or may be subjected to a polycondensation reaction in sequence. .

The temperature at which the tetracarboxylic dianhydride component and the diamine component are subjected to a polycondensation reaction in an organic solvent is usually 0 to 150 ° C, preferably 5 to 100 ° C, more preferably 10 to 80 ° C. The higher the temperature, the earlier the polycondensation reaction ends, but when the temperature is too high, a polymer having a high molecular weight may not be obtained.

Further, the polycondensation reaction can be carried out at any concentration. However, when the total mass concentration of the tetracarboxylic dianhydride component and the diamine component is too low, a polymer having a high molecular weight cannot be obtained, and the total of the tetracarboxylic dianhydride component and the diamine component is not obtained. When the mass concentration is too high, the viscosity of the reaction liquid is too high to be uniformly stirred, and it is preferably from 1 to 50% by mass, more preferably from 5 to 30% by mass. The polycondensation reaction is carried out at a high concentration in the initial stage, and then an organic solvent may be added.

The organic solvent used in the above reaction is not particularly limited as long as it can dissolve only the produced polyamic acid. To cite such a specific example, N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, and N-ethyl-2-pyrrolidone are mentioned. , 1,3-dimethylimidazolidinone, N-methyl caprolactam, dimethyl hydrazine, tetramethyl urea, pyridine, dimethyl hydrazine, hexamethyl fluorene, γ-butyrolactone Wait. These can be used alone or in combination. Further, it may be a solvent in which polylysine is not dissolved, and may be used in the above solvent in the range in which the produced polyamic acid is not precipitated.

Further, since the water in the organic solvent hinders the polycondensation reaction and becomes a cause of the polylysine produced by the hydrolysis, it is preferred that the organic solvent be desalted as much as possible.

The ratio of the tetracarboxylic dianhydride component to the diamine component used in the polycondensation reaction of polyamic acid is preferably 1:0.8 to 1:1.2 in terms of molar ratio, and the molar ratio is closer to 1:1. The molecular weight of the obtained polyamic acid is larger. By controlling the molecular weight of the polyaminic acid, the molecular weight of the soluble polyimine obtained after imidization can be adjusted.

The molecular weight of the soluble polyimine contained in the liquid crystal alignment treatment agent of the present invention is not particularly limited, and the weight average molecular weight is 2,000 to 200,000 from the viewpoint of the strength of the coating film and the ease of handling as a liquid crystal alignment treatment agent. Preferably, it is preferably 5,000 to 50,000.

The imidization of the polyamic acid obtained as described above is preferably carried out in an organic solvent in the presence of a basic catalyst and an acid anhydride for 1 to 100 hours.

Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine. Among them, pyridine is preferred because it has a basicity suitable for carrying out the reaction.

Further, examples of the acid anhydride include acetic anhydride, trimellitic anhydride, and pyromellitic anhydride. Among them, acetic anhydride is also preferred since the imidization is completed, and the obtained polyimine is easily purified. As the organic solvent, a solvent used in the polycondensation reaction of the above polyamic acid can be used.

The imidization ratio of the soluble polyimine can be controlled by adjusting the amount of the catalyst, the reaction temperature, and the reaction time. The amount of the alkaline catalyst at this time is preferably 0.2 to 10 moles of the amidate group, preferably 0.5 to 5 moles. Further, the amount of the acid anhydride is preferably from 1 to 30 moles of the valeric acid group, preferably from 1 to 10 moles. The reaction temperature is preferably -20 to 250 ° C, preferably 0 to 180 ° C. The reaction time is preferably from 1 to 100 hours, preferably from 1 to 20 hours.

The imidization ratio of the soluble polyimine contained in the liquid crystal alignment agent of the present invention is not particularly limited, and is preferably 40% or more, and preferably 60% or more, preferably 80%. %the above.

Further, in the present invention, the imidization ratio of the polyimine can be measured as follows. 20 mg of polyimine powder was placed in an NMR (Nuclear Magnetic Resonance Absorption) sampling tube, and 0.53 ml of dimethyl hydrazine (DMSO-d ₆ , 0.05% TMS (tetramethyl decane) mixture) was added thereto to make it completely dissolved. This solution was measured for proton NMR at 500 MHz using a NMR measuring instrument (JNM-ECA500) manufactured by JEOL DATUM.

The imidization ratio of the soluble polyimine is determined by using protons having a structure unchanged from before and after imidization as a reference proton, and the peak value of the proton is used, and the proline acid from the vicinity of 9.5 to 10.0 ppm is used. The peak value of the proton wave peak of the NH group is obtained by the following formula.

Amination rate (%) = (1-α‧x/y) × 100

In the above formula, x is the proton peak value of the NH group derived from proline, y is the peak value of the reference proton, and α is the polyamine (the imidization rate is 0%). The ratio of the number of reference protons of one NH matrix of acid.

In the solution of the soluble polyimine thus obtained, since the added catalyst or the like remains, it is preferable to recover the soluble polyimine from the solvent and then use the liquid crystal alignment agent of the present invention.

The recovery of the soluble polyimine is carried out by adding a weak solvent to the solution after stirring and imidization, and precipitating the polyimine and then filtering. Examples of the weak solvent at this time include methanol, acetone, hexane, butyl sirolimus, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, and the like. The washing of the recovered soluble polyimine can also be carried out with the weak solvent.

The polyimine which is thus recovered and washed may be powdered under normal pressure or reduced pressure at room temperature or by heating.

The liquid crystal alignment treatment agent of the present invention contains a polyamic acid and/or a soluble polyimine obtained by using a diamine component containing a diamine represented by the formula [1] and a diamine represented by the formula [2]. It may be referred to as polylysine and/or soluble polyimine of the present invention, but may also contain, in addition to a suitable ratio of polylysine and/or soluble polyimine. At this time, the content of the poly-proline and/or the soluble polyimine of the present invention is from the viewpoint of the appropriate tilt angle ‧ alignment, and for the total polyamine and/or the soluble polyimide It is preferably 10 to 90% by mass, more preferably 10 to 40% by mass.

The liquid crystal alignment treatment agent of the present invention contains at least one polymer of the above polyamic acid and soluble polyimine, but may contain only polylysine alone or may contain only soluble polyimine. In order to obtain better printability or good afterimage characteristics, it can be made into a liquid crystal alignment treatment agent which contains polyacrylic acid and soluble polyimine at an appropriate ratio. In the present invention, the content of the soluble polyimine contained in the liquid crystal alignment agent is preferably 10 to 50% by mass, and 10 to 10% by weight based on the total content of the soluble polyimine and the polyamic acid. 30% by mass is more preferred.

The method for preparing the liquid crystal alignment agent of the present invention is not particularly limited. To cite one of them, a method of diluting the polyamic acid solution obtained as described above to a desired concentration is used. Further, the soluble polyimine solution is a method in which the powder of the soluble polyimine obtained as described above is redissolved in an organic solvent to obtain a polyimine solution, followed by dilution to a desired concentration. In the dilution step, adjustment of the solvent composition for controlling the coating property to the substrate, addition of an additive for improving the properties of the coating film, or the like can be performed.

Further, a solution of the soluble polyimine of the above-described different structure or a solution of a polyamic acid solution or another resin component may be added.

Examples of the organic solvent for diluting polyamic acid or the organic solvent for re-dissolving the polyimine powder include N,N-dimethylformamide, N,N-dimethylacetamide, and N. -Methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-methylcaprolactam, 2-pyrrolidone, N-vinylpyrrolidone, dimethyl hydrazine, tetramethyl urea, dimethyl Anthraquinone, hexamethylarylene, γ-butyrolactone, 1,3-dimethyl-imidazolidinone, and the like.

Examples of the solvent to be added to control the applicability to the substrate include ethyl sirlox, butyl sirolimus, ethyl carbitol, butyl carbitol, ethyl carbitol acetate, Ethylene glycol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanol, propylene glycol Acetate, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2-(2-ethoxyl) Propyl alcohol) propanol, methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, isoamyl lactate, and the like. Although these solvents contain a solvent which cannot dissolve polyphosphoric acid or soluble polyimine alone, it may be mixed in the liquid crystal alignment of the present invention insofar as it does not precipitate polyamic acid or polyimine. Treatment agent. In particular, it is known that the uniformity of the coating film when the substrate is applied can be improved by appropriately mixing a solvent having a low surface tension, and is also applicable to the liquid crystal alignment treatment agent of the present invention.

Examples of the additive to improve the characteristics of the coating film include 3-aminopropylmethyldiethoxydecane, 3-phenylaminopropyltrimethoxydecane, and 3-aminopropyltriethoxylate. A decane coupling agent such as decane or (aminoethylaminomethyl)phenethyltrimethoxydecane. By the addition of these decane coupling agents, the coating film adhesion to the substrate can be further improved.

The solid content concentration of the liquid crystal alignment agent of the present invention can be appropriately changed by setting the thickness of the liquid crystal alignment film to be formed, and is preferably 0.5 to 10% by mass, more preferably 1 to 8% by mass. When it is less than 0.5% by mass, it is difficult to form a uniform and non-defective coating film, and when it is more than 10% by mass, the storage stability of the solution may be deteriorated. Here, the solid component is a component which removes a solvent from a liquid crystal alignment treatment agent.

It is preferred that the liquid crystal alignment treatment agent obtained above is filtered before being applied to a substrate.

The liquid crystal alignment treatment agent of the present invention can be applied to a substrate, dried, and fired to form a coating film, and the coating film surface can be used as a liquid crystal alignment film by rubbing treatment.

In this case, the substrate to be used is not particularly limited as long as it is a substrate having high transparency, and a plastic substrate such as a glass substrate, an acrylic substrate or a polycarbonate substrate can be used, and liquid crystal driving is used. When a substrate such as an ITO electrode is formed, it is preferable from the viewpoint of simplification of the process. Further, the reflective liquid crystal display element may be a single-sided substrate, and an opaque substance such as a wafer may be used. In this case, a material that reflects light such as aluminum may be used as the electrode.

Examples of the coating method of the liquid crystal alignment treatment agent include a spin coating method, a printing method, and an inkjet printing method. From the viewpoint of productivity, the elastic printing method is widely used in the industry, and is also suitable for the liquid crystal alignment of the present invention. In the treatment agent.

Although the drying step after the application of the liquid crystal alignment agent is not necessary, the drying step is preferably carried out from the time after the application to the time of baking to each substrate, or when it is not immediately after the application. This drying is such that the solvent is evaporated so as not to be deformed by the shape of the coating film due to the conveyance of the substrate, and the drying means is not particularly limited. Specific examples thereof include a method of drying at 50 to 150 ° C, preferably 80 to 120 ° C for 0.5 to 30 minutes, more preferably 1 to 5 minutes.

The baking of the substrate coated with the liquid crystal alignment agent can be carried out at any temperature of 100 to 350 ° C, preferably 150 ° C to 300 ° C, more preferably 180 ° C to 250 ° C. When the proline group is present in the liquid crystal alignment agent, the conversion ratio from valeric acid to imine at the firing temperature varies, but the liquid crystal alignment treatment agent of the present invention does not have to be 100% imidized. However, in the heat treatment temperature such as curing of the sealing agent which is considered to be necessary for the production process of the liquid crystal cell, it is preferred to carry out the firing at a high temperature of 10 ° C or higher.

When the thickness of the coating film after firing is too thick, it is disadvantageous in view of the power consumption of the liquid crystal display element. When it is too thin, the reliability of the liquid crystal display element may be lowered, preferably 10 to 200 nm. Good is 50 to 100 nm.

As the above-described rubbing treatment of the coating film surface formed on the substrate, a known friction device can be used. Examples of the material of the rubbing cloth at this time include cotton, crepe, nylon, and the like.

In the liquid crystal display device of the present invention, the liquid crystal alignment cell is obtained by the liquid crystal alignment film of the present invention, and the liquid crystal cell is produced by a known method to form a liquid crystal display device.

To exemplify the production of a liquid crystal cell, a pair of substrates forming a liquid crystal alignment film is formed, and a spacer of preferably 1 to 30 μm, more preferably 2 to 10 μm, is disposed, and the rubbing direction is set to any angle of 0 to 270°. And the method of fixing the surrounding with a sealing agent, injecting the liquid crystal and sealing it is general. The method of encapsulating the liquid crystal is not particularly limited, and a vacuum method in which liquid crystal is produced under reduced pressure, a vacuum method in which liquid crystal is injected, a dropping method in which liquid crystal is dropped, and sealing is exemplified.

The liquid crystal display element thus obtained is excellent in liquid crystal alignment, and is poor in alignment failure due to damage of the liquid crystal alignment film or peeling of the film during rubbing treatment, and reduction in pretilt angle at a high temperature, and reliability can be obtained. Since it is a liquid crystal display device with high performance, it can be applied to various types of display elements such as a TN liquid crystal display element, an STN liquid crystal display element, a TFT liquid crystal display element, and an OCB liquid crystal display element.

[Examples]

The invention will be described in more detail below by way of examples, without however limited thereto.

The abbreviations of the compounds used in the examples and comparative examples are as follows.

<tetracarboxylic dianhydride>

CA1: 4-(2,5-di-sided oxytetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic anhydride

CA2: 1,2,3,4-cyclobutane tetracarboxylic dianhydride

CA3: [3,3,0]bicyclooctane-2,3,5,6-tetracarboxylic dianhydride

CA4: pyromellitic dianhydride

<Diamine>

DA1: 2,4-diamine-N,N-diallylaniline

DA2: 1,3-diamine-4-octadecyloxybenzene

DA3: 4-(trans-4-pentylcyclohexyl)benzamide-2',4'-phenylenediamine

DA4: p-phenylenediamine

DA5: 4-{4-(4-heptylcyclohexyl)phenoxy}-1,3-diamine benzene

DA6: 4-aminobenzylamine

DA7: 3-aminobenzylamine

DA8: 1,3-diamine-4-dodecyloxybenzene

DA9: bis(4-aminophenyl)methane

DA10: 1,3-diamine-4-tetradecyloxybenzene

<organic solvent>

NMP: N-methyl-2-pyrrolidone

γBL: γ-butyrolactone

BC: Butyl Cyrus

The evaluation method performed in the present embodiment will be described below.

<Measurement of molecular weight>

The molecular weight of the polyaminic acid and the polyimine is measured by a GPC (normal temperature gel permeation chromatography) apparatus, and is calculated as a polyethylene glycol or polyethylene oxide equivalent value. Number average molecular weight and weight average molecular weight.

GPC device: manufactured by Shodex (GPC-101)

Pipe column: made by Shodex company (inline of KD803, KD805)

Column temperature: 50 ° C

Dissolution: N,N-dimethylformamide (as additive with lithium bromide-water and (LiBr‧H ₂ O) 30 mmole/L, phosphoric acid ‧ anhydrous crystals (o-phosphoric acid) 30 mmole/L, tetrahydrofuran (THF) 10ml/L)

Flow rate: 1.0ml/min

Standard sample for proofreading curve: TSK standard polyethylene oxide (molecular weight: about 900,000, 150,000, 100,000, 30,000) manufactured by Tosoh Corporation, and polyethylene glycol (molecular weight of about 12,000, 4,000, 1,000) manufactured by POLYMER LABORATORY. .

<Measurement of imidization rate>

The imidization ratio of polyimine was determined as follows. 20 mg of polyimine powder was placed in an NMR (Nuclear Magnetic Resonance Absorption) sampling tube, and 0.53 ml of dimethyl hydrazine (DMSO-d ₆ , 0.05% TMS (tetramethyl decane) mixture) was added to make it completely complete. Dissolved. This solution was measured for proton NMR at 500 MHz using a NMR measuring instrument (JNM-ECA500) manufactured by JEOL DATUM. The imidization ratio is determined by using protons having a structure unchanged from before and after imidization as a reference proton, and the peak value of the proton and the protons from the NH group derived from 9.5 to 10.0 ppm of proline are used. The peak value is obtained by the following formula.

Amination rate (%) = (1-α‧x/y) × 100

In the above formula, x is the proton peak product of the NH group of the proline, y is the peak value from the reference proton, and α is the polyproline (the imidization rate is 0%). The ratio of the number of reference protons of one NH matrix of the amine acid.

<Production of liquid crystal cells>

The liquid crystal alignment treatment agent was spin-coated on a glass substrate with a transparent electrode, dried on a hot plate at 70 ° C for 70 seconds, and then fired on a hot plate at 210 ° C for 10 minutes to form a coating having a thickness of 100 nm. membrane. This coating film surface was rubbed with a rubbing apparatus having a roll diameter of 120 mm, and rubbed under the conditions of a roll rotation speed of 1000 rpm, a roll speed of 50 mm/sec, and a press-in amount of 0.3 mm to obtain a substrate having a liquid crystal alignment film.

Two sheets of the substrate were prepared, and a spacer of 6 μm was spread on the liquid crystal alignment film surface of the one sheet, and a sealing agent was applied thereon, and the other substrate was faced to the liquid crystal alignment film surface, and the rubbing direction was straightly bonded. A hollow cell that hardens the sealant is produced. The hollow cell was injected into a liquid crystal MLC-2003 (manufactured by Melt Japan Co., Ltd.) by a vacuum injection method, and a twisted nematic liquid crystal cell was obtained after the injection port was sealed.

<Measurement of pretilt angle>

The obtained liquid crystal cell was used in the same manner as in the above <Production of Liquid Crystal Cell>, and the pretilt angle was measured. The measurement was performed using TBA107 manufactured by Autronic Corporation. The measurement was carried out under the conditions of heating (23 ° C) and maintaining the liquid crystal cell at 60 ° C, and the amount of change in the pretilt angle before and after heating was evaluated.

<Evaluation of friction resistance>

In the above-mentioned <production of liquid crystal cell>, the press-fitting of the rubbing roller was changed to 0.5 mm, and rubbing was performed to produce a substrate with a liquid crystal alignment film. The surface of the liquid crystal alignment film was observed under a laser microscope, and the following evaluation was carried out under visual observation.

○: There is almost no slag or frictional damage.

△: Slag is generated or there is a frictional injury.

×: The film was peeled off. It was observed that the friction wound became a strip.

<Evaluation of liquid crystal alignment>

In the above <Production of Liquid Crystal Cell>, the press-fitting of the rubbing roller was changed to 0.2 mm, and liquid crystal cells (anti-parallel) were produced under the same conditions. At this time, the presence or absence of the liquid crystal flow alignment was observed from the injection port of the liquid crystal cell at the time of liquid crystal injection, and the following evaluation was performed.

○: No flow alignment was observed.

×: Most strip flow alignments were observed.

[Example 1]

12.49 g (42 mmol) of CA1 as a tetracarboxylic dianhydride component, 2.73 g (25 mmol) of DA4 as a diamine component, 3.43 g (8.4 mmol) of DA3, and 1.71 g (8.4 mmol) of DA1 were used. The reaction was carried out for 24 hours at room temperature in 81.37 g of NMP to obtain a polyaminic acid solution. To 95.8 g of the polyamic acid solution, 242.7 g of NMP was added and diluted, and 42.81 g of acetic anhydride and 19.91 g of pyridine were added, and the mixture was reacted at 40 ° C for 3 hours to imidize. The reaction solution was cooled to room temperature, and then poured into 1404.1 ml of methanol to recover a precipitated solid. Further, the solid matter was washed several times with methanol, and then dried under reduced pressure at a temperature of 100 ° C to obtain a white powder of soluble polyimine (SPI-1). The polyimine had a number average molecular weight of 12,207 and a weight average molecular weight of 40,065. Further, the imidization ratio was 85%. To 1.2 g of the polyimide pigment, 10.8 g of γBL was added, and the mixture was stirred at a temperature of 50 ° C for 24 hours. At the end of the agitation, the polyimine was completely dissolved. After cooling 12 g of this solution to 23 ° C, 2 g of γBL and 6 g of BC were added, and the mixture was stirred at a temperature of 50 ° C for 20 hours. After the completion of the stirring, the mixture was cooled to 23 ° C to obtain a uniform liquid crystal alignment treatment agent.

The liquid crystal alignment treatment agent was used to evaluate the friction resistance, the alignment property, and the tilt angle. The results are shown in Table 2.

[Embodiment 2]

6.20 g (22 mmol) of CA1, 5.38 g (22 mmol) of CA3 as a tetracarboxylic dianhydride component, 2.79 g (26 mmol) of DA4 as a diamine component, 3.51 g (8.6 mmol) of DA3, and 1.75 were further used. g (8.6 mmol) of DA1 was reacted in NMP 78.49 g at 80 ° C for 24 hours to obtain a polyaminic acid solution. To 50 g of the polyamic acid solution, 114.3 g of NMP was added and diluted, and 6.34 g of acetic anhydride and 9.84 g of pyridine were added, and the mixture was reacted at 100 ° C for 3 hours to imidize. After cooling the reaction solution to room temperature, it was poured into 631.7 ml of methanol, and the precipitated solid matter was collected. Further, the solid matter was washed several times with methanol, and then dried under reduced pressure at a temperature of 100 ° C to obtain a white powder of polyimine (SPI-2). The polyimine had a number average molecular weight of 10,250 and a weight average molecular weight of 49,802. Further, the imidization ratio was 82%. To 1.2 g of the polyimide pigment, 10.8 g of γBL was added, and the mixture was stirred at a temperature of 50 ° C for 24 hours. At the end of the agitation, the polyimine was completely dissolved. After cooling 12 g of this solution to 23 ° C, 2 g of γBL and 6 g of BC were added, and the mixture was stirred at a temperature of 50 ° C for 20 hours. After the completion of the stirring, the mixture was cooled to 23 ° C to obtain a uniform liquid crystal alignment treatment agent.

The liquid crystal alignment treatment agent was used to evaluate the friction resistance, the alignment property, and the tilt angle. The results are shown in Table 2.

[Example 3]

7.68 g (40 mmol) of CA2 as a tetracarboxylic dianhydride component, 2.60 g (24 mmol) of DA4 as a diamine component, 3.42 g (8.4 mmol) of DA3, and 1.63 g (8.4 mmol) of DA1 were used in NMP85. In .96 g, a polyamine acid (PAA-1) solution was obtained after 24 hours of reaction at room temperature. The polyamine had a number average molecular weight of 18,374 and a weight average molecular weight of 43,407. To 8 g of this solution, 10.5 g of NMP and 7.5 g of BC were added, and the mixture was stirred at room temperature for 20 hours to obtain a uniform liquid crystal alignment treatment agent.

The liquid crystal alignment treatment agent was used to evaluate the friction resistance, the alignment property, and the tilt angle. The results are shown in Table 2.

[Example 4]

8.18 g (42 mmol) of CA2, 1.63 g (7.5 mmol) of CA4 as a tetracarboxylic dianhydride component, 1.22 g (10 mmol) of DA7 as a diamine component, 5.08 g (25 mmol) of DA1, 6.11 g ( 15 mmol) of DA3 was reacted in NMP 88.96 g at room temperature for 24 hours to obtain a polyaminic acid solution. 95.8 g of this polyaminic acid solution was added to 228.5 g of NMP, and 15.1 g of acetic anhydride and 6.4 g of pyridine were added, and the reaction was imidized at a temperature of 50 ° C for 3 hours. The reaction solution was cooled to room temperature, and then poured into 1259.1 ml of methanol to recover a precipitated solid. Further, the solid matter was washed several times with methanol, and then dried under reduced pressure at a temperature of 100 ° C to obtain a white powder of soluble polyimine (SPI-3). The polyimine had a number average molecular weight of 18,195 and a weight average molecular weight of 57,063. Further, the imidization ratio was 93%. To 1.2 g of the polyimide pigment, 10.8 g of γBL was added, and the mixture was stirred at a temperature of 50 ° C for 24 hours. At the end of the agitation, the polyimine was completely dissolved. After cooling 12 g of this solution to 23 ° C, 2 g of γBL and 6 g of BC were added, and the mixture was stirred at a temperature of 50 ° C for 20 hours. After the completion of the stirring, the mixture was cooled to 23 ° C to obtain a uniform liquid crystal alignment treatment agent.

The liquid crystal alignment treatment agent was used to evaluate the friction resistance, the alignment property, and the tilt angle. The results are shown in Table 2.

[Example 5]

13.53 g (69 mmol) of CA2, 6.54 g (30 mmol) of CA4 as a tetracarboxylic dianhydride component, 8.13 g (40 mmol) of DA1 as a diamine component, 3.67 g (30 mmol) of DA6, and 8.77 g (30 mmol) were used. DA8 was reacted in NMP 161.8 g at room temperature for 24 hours to obtain a polyaminic acid solution.

34.81 g of the polyamic acid solution was added to 62.65 g of NMP, and 5.15 g of acetic anhydride and 2.19 g of pyridine were added, and the reaction was imidized at a temperature of 50 ° C for 3 hours.

After cooling the reaction solution to room temperature, it was poured into 366.8 ml of methanol, and the precipitated solid matter was collected. Further, the solid matter was washed several times with methanol, and then dried under reduced pressure at a temperature of 100 ° C to obtain a white powder of polyimine (SPI-4). The polyimine had a number average molecular weight of 12,016 and a weight average molecular weight of 35,126. Further, the imidization ratio was 90%.

To 1.2 g of the polyimide pigment, 10.8 g of γBL was added, and the mixture was stirred at a temperature of 50 ° C for 24 hours. At the end of the agitation, the polyimine was completely dissolved. After cooling 12 g of this solution to 23 ° C, 2 g of γBL and 6 g of BC were added, and the mixture was stirred at a temperature of 50 ° C for 20 hours. After the completion of the stirring, the mixture was cooled to 23 ° C to obtain a uniform liquid crystal alignment treatment agent.

The mass ratio of the SPI-4 to SPI-3 was mixed to 7:3 to obtain the liquid crystal alignment treatment agent of the present invention. The liquid crystal alignment treatment agent was used to evaluate the friction resistance, the alignment property, and the tilt angle. The results are shown in Table 2.

[Embodiment 6]

6.86 g (35 mmol) of CA2, 3.27 g (15 mmol) of CA4 as a tetracarboxylic dianhydride component, 2.44 g (20 mmol) of DA7 as a diamine component, 3.04 g (15 mmol) of DA1, 6.11 g (15 mmol) were used. DA3 was obtained by reacting for 24 hours at room temperature in NMP 87.0 g to obtain a polyaminic acid solution (PAA-2). The polyamine had a number average molecular weight of 15,539 and a weight average molecular weight of 47,210. To 8 g of this solution, 10.5 g of NMP and 7.5 g of BC were added, and the mixture was stirred at room temperature for 20 hours to obtain a uniform liquid crystal alignment treatment agent.

The mass ratio of the PAA-2 to SPI-3 was 8:2, and the liquid crystal alignment treatment agent of the present invention was obtained. The liquid crystal alignment treatment agent was used to evaluate the friction resistance, the alignment property, and the tilt angle. The results are shown in Table 2.

[Embodiment 7]

9.80 g (50 mmol) of CA2, 9.60 g (44 mmol) of CA4 as a tetracarboxylic dianhydride component, and 19.8 g (100 mmol) of DA9 as a diamine component were used in NMP 222 g at room temperature for 5 hours. A polylysine solution (PAA-3) was obtained. The polyamine had a number average molecular weight of 11,153 and a weight average molecular weight of 29,487. To 8 g of this solution, 10.5 g of NMP and 7.5 g of BC were added, and the mixture was stirred at room temperature for 20 hours to obtain a uniform liquid crystal alignment treatment agent.

The mass ratio of the PAA-3 to the PAA-1 was 5:5 to obtain the liquid crystal alignment treatment agent of the present invention. The liquid crystal alignment treatment agent was used to evaluate the friction resistance, the alignment property, and the tilt angle. The results are shown in Table 2.

[Embodiment 8]

The mass ratio of the mixed SPI-3 to SPI-4 to PAA-3 was 1:1:8 to obtain the liquid crystal alignment treatment agent of the present invention. The liquid crystal alignment treatment agent was used to evaluate the friction resistance, the alignment property, and the tilt angle. The results are shown in Table 2.

[Embodiment 9]

7.84 g (40 mmol) of CA2 as a tetracarboxylic dianhydride component, and 6.51 g (32 mmol) of DA1 and 3.26 g (8 mmol) of DA3 as a diamine component were used in NMP 70.4 g at room temperature for 24 hours. The reaction gave a polyaminic acid solution. The polyamine had a number average molecular weight of 14,119 and a weight average molecular weight of 39,572. To 8 g of this solution, 10.5 g of NMP and 7.5 g of BC were added, and the mixture was stirred at room temperature for 20 hours to obtain a homogeneous polyamine acid solution (PAA-4). This solution was used as a liquid crystal alignment treatment agent. The liquid crystal alignment treatment agent was used to evaluate the friction resistance, the alignment property, and the tilt angle. The results are shown in Table 2.

[Comparative Example 1]

Using 13.38 g (45 mmol) of CA1 as a tetracarboxylic dianhydride component, 3.89 g (36 mmol) of DA4 as a diamine component, and 3.67 g (9 mmol) of DA3, in NMP 83.76 g, at room temperature for 24 hours. The reaction gave a polyaminic acid solution. To 98.5 g of the polyamic acid solution, 256.1 g of NMP was added and diluted, and 46.68 g of acetic anhydride and 21.71 g of pyridine were added, and the mixture was subjected to a reaction at 40 ° C for 3 hours to imidize. After cooling the reaction solution to room temperature, it was poured into 1480.5 ml of methanol, and the precipitated solid matter was collected. Further, the solid matter was washed several times with methanol, and then dried under reduced pressure at a temperature of 100 ° C to obtain a white powder of polyimine (SPI-T1). The polyimine had a number average molecular weight of 12,120 and a weight average molecular weight of 35,728. Further, the imidization ratio was 85%. To 1.2 g of the polyimide pigment, 10.8 g of γBL was added, and the mixture was stirred at a temperature of 50 ° C for 24 hours. At the end of the agitation, the polyimine was completely dissolved. After cooling 12 g of this solution to 23 ° C, 2 g of γBL and 6 g of BC were added, and the mixture was stirred at a temperature of 50 ° C for 20 hours. After the completion of the stirring, the mixture was cooled to 23 ° C to obtain a homogeneous polyimine solution. This solution was used as a liquid crystal alignment treatment agent.

The liquid crystal alignment treatment agent was used to evaluate the friction resistance, the alignment property, and the tilt angle. The results are shown in Table 2.

[Comparative Example 2]

6.48 g (23 mmol) of CA1, 5.63 g (23 mmol) of CA3 as a tetracarboxylic dianhydride component, 3.89 g (36 mmol) of DA4 as a diamine component, 3.67 g (9 mmol) of DA3, and NMP 78.71 g were used. The reaction was carried out at 80 ° C for 24 hours to obtain a polyaminic acid solution. To 50 g of the polyamic acid solution, 110 g of NMP was added and diluted, and 6.45 g of acetic anhydride and 9.99 g of pyridine were added, and the mixture was reacted at 100 ° C for 3 hours to imidize. After cooling the reaction solution to room temperature, it was poured into 617.6 ml of methanol, and the precipitated solid matter was collected. Further, the solid matter was washed several times with methanol, and then dried under reduced pressure at a temperature of 100 ° C to obtain a white powder of soluble polyimine (SPI-T2). The polyimine had a number average molecular weight of 12,105 and a weight average molecular weight of 74,076. Further, the imidization ratio was 82%. To 1.2 g of the polyimide pigment, 10.8 g of γBL was added, and the mixture was stirred at a temperature of 50 ° C for 24 hours. At the end of the agitation, the polyimine was completely dissolved. After cooling 12 g of this solution to 23 ° C, 2 g of γBL and 6 g of BC were added, and the mixture was stirred at a temperature of 50 ° C for 20 hours. After the completion of the stirring, the mixture was cooled to 23 ° C to obtain a homogeneous polyimine solution. This solution was used as a liquid crystal alignment treatment agent.

The liquid crystal alignment treatment agent was used to evaluate the friction resistance, the alignment property, and the tilt angle. The results are shown in Table 2.

[Comparative Example 3]

8.07 g (42 mmol) of CA2 as a tetracarboxylic dianhydride component, 3.63 g (34 mmol) of DA4 as a diamine component, and 3.26 g (8 mmol) of DA3 as a diamine component were used in NMP 85.73 g at room temperature. After a few hours of reaction, a solution of poly-proline (PAA-T1) was obtained. The proline had a number average molecular weight of 26,985 and a weight average molecular weight of 66,365. To 8 g of this solution, 10.5 g of NMP and 7.5 g of BC were added, and the mixture was stirred at room temperature for 20 hours to obtain a homogeneous polyamine acid solution. This solution was used as a liquid crystal alignment treatment agent.

The liquid crystal alignment treatment agent was used to evaluate the friction resistance, the alignment property, and the tilt angle. The results are shown in Table 2.

[Comparative Example 4]

30.03 g (100 mmol) of CA1 as a tetracarboxylic dianhydride component, 9.73 g (90 mmol) of DA4 as a diamine component, and 3.77 g (10 mmol) of DA2 as a diamine component were reacted in NMP 247 g at 40 °C for 3 hours. After that, a polyaminic acid solution was obtained.

50 g of the polyaminic acid solution was diluted to 5 wt% with NMP, and 17.6 g of acetic anhydride as an imidization catalyst and 8.2 g of pyridine were added thereto, and the reaction was carried out at 40 ° C for 3 hours to prepare a soluble polyimine. Resin solution. This solution was poured into 0.6 L of methanol, and the obtained precipitate was separated by filtration and dried to give white soluble polyimine (SPI-T3). The molecular weight of the soluble polyimine was measured, and the number average molecular weight was 13,430, and the weight average molecular weight was 26,952. Further, the imidization ratio was 85%. 1 g of this polyimine powder was dissolved in γBL 11.8 g and BC 4.8 g to obtain a uniform polyimine solution. This solution was used as a liquid crystal alignment treatment agent.

The liquid crystal alignment treatment agent was used to evaluate the friction resistance, the alignment property, and the tilt angle. The results are shown in Table 2.

[Comparative Example 5]

5.59 g (29 mmol) of CA2 as a tetracarboxylic dianhydride component, 3.08 g (28 mmol) of DA4 as a diamine component, and 0.571 g (1.5 mmol) of DA5 as a diamine component were used in NMP 83.18 g at room temperature. A polyamine acid (PAA-T2) solution was obtained after 24 hours of reaction. The polyamine had a number average molecular weight of 17,630 and a weight average molecular weight of 41,068. 2 g of NMP and 6 g of BC were added to 12 g of this solution, and the mixture was stirred at room temperature for 20 hours to obtain a homogeneous polyamine acid solution. This solution was used as a liquid crystal alignment treatment agent.

The liquid crystal alignment treatment agent was used to evaluate the friction resistance, the alignment property, and the tilt angle. The results are shown in Table 2.

[Comparative Example 6]

5.59 g (29 mmol) of CA2 as a tetracarboxylic dianhydride component, 2.43 g (23 mmol) of DA4 as a diamine component, 0.571 g (1.5 mmol) of DA5, and 1.219 g (6 mmol) of DA1 were used in NMP83. In 18 g, a polyamine acid (PAA-T3) solution was obtained after 24 hours of reaction at room temperature. The polyamic acid had a number average molecular weight of 16,132 and a weight average molecular weight of 34,880. 2 g of NMP and 6 g of BC were added to 12 g of this solution, and the mixture was stirred at room temperature for 20 hours to obtain a homogeneous polyamine acid solution. This solution was used as a liquid crystal alignment treatment agent.

The liquid crystal alignment treatment agent was used to evaluate the friction resistance, the alignment property, and the tilt angle. The results are shown in Table 2.

[Comparative Example 7]

13.53 g (69 mmol) of CA2, 6.54 g (30 mmol) of CA4 as a tetracarboxylic dianhydride component, 9.62 g (30 mmol) of DA10 as a diamine component, 6.10 g (30 mmol) of DA1, 4.89 g (40 mmol) were used. DA7 was reacted in NMP 162.7 g at room temperature for 24 hours to obtain a polyaminic acid solution. 35.79 g of the polyamic acid solution was added and diluted with 63.91 g of NMP, and 5.16 g of acetic anhydride and 2.20 g of pyridine were added, and the reaction was imidized at a temperature of 50 ° C for 3 hours.

After the reaction solution was cooled to room temperature, it was poured into 374.7 ml of methanol, and the precipitated solid matter was collected. Further, the solid matter was washed several times with methanol, and then dried under reduced pressure at a temperature of 100 ° C to obtain a white powder of polyimine (SPI-T4). The polyimine had a number average molecular weight of 13,472 and a weight average molecular weight of 35,859. Further, the imidization ratio was 89%.

To 1.2 g of the polyimide pigment, 10.8 g of γBL was added, and the mixture was stirred at a temperature of 50 ° C for 24 hours. At the end of the agitation, the polyimine was completely dissolved. After cooling 12 g of this solution to 23 ° C, 2 g of γBL and 6 g of BC were added, and the mixture was stirred at a temperature of 50 ° C for 20 hours. After the completion of the stirring, the mixture was cooled to 23 ° C to obtain a uniform liquid crystal alignment treatment agent.

The mass ratio of the SPI-T4 to SPI-4 was 3:7 to obtain the liquid crystal alignment treatment agent of the present invention. The liquid crystal alignment treatment agent was used to evaluate the friction resistance, the alignment property, and the tilt angle. The results are shown in Table 2.

[Comparative Example 8]

13.33 g (68 mmol) of CA2, 6.54 g (30 mmol) of CA4 as a tetracarboxylic dianhydride component, 3.81 g (10 mmol) of DA5 as a diamine component, 8.13 g (40 mmol) of DA1, 7.64 g (50 mmol) were used. DA6 was reacted in NMP 151.7 g at room temperature for 24 hours to obtain a polyaminic acid solution. 33.38 g of the polyamic acid solution was added and diluted with 59.61 g of NMP, and 5.26 g of acetic anhydride and 2.24 g of pyridine were added, and the reaction was carried out for 3 hours at a temperature of 50 ° C to imidize.

After cooling the reaction solution to room temperature, it was poured into 351.7 ml of methanol, and the precipitated solid matter was collected. Further, the solid matter was washed several times with methanol, and then dried under reduced pressure at a temperature of 100 ° C to obtain a white powder of polyimine (SPI-T5). The polyimine had a number average molecular weight of 10,111 and a weight average molecular weight of 33,653. Further, the imidization ratio was 90%.

To 1.2 g of the polyimide pigment, 10.8 g of γBL was added, and the mixture was stirred at a temperature of 50 ° C for 24 hours. At the end of the agitation, the polyimine was completely dissolved. After cooling 12 g of this solution to 23 ° C, 2 g of γBL and 6 g of BC were added, and the mixture was stirred at a temperature of 50 ° C for 20 hours. After the completion of the stirring, the mixture was cooled to 23 ° C to obtain a uniform liquid crystal alignment treatment agent.

The mass ratio of the SPI-T5 to SPI-4 was 3:7, and the liquid crystal alignment treatment agent of the present invention was obtained. The liquid crystal alignment treatment agent was used to evaluate the friction resistance, the alignment property, and the tilt angle. The results are shown in Table 2.

In Table 1, "-" indicates that the diamine was not used as a raw material of polyamic acid or polyimine.

[Industrial availability]

The liquid crystal display device produced by using the liquid crystal alignment treatment agent of the present invention can be used as a liquid crystal display device having high reliability, and can be applied to display by various methods such as a TN liquid crystal display element, an STN liquid crystal display element, a TFT liquid crystal display element, and an OCB liquid crystal display element. element.

The contents of the specification, the scope of the patent application, and the abstract of the Japanese Patent Application No. 2008-272410, filed on Oct. 22, 2008, are hereby incorporated by reference.

Claims (9)

A liquid crystal alignment treatment agent comprising a polymer comprising at least one of a polyaminic acid obtained by reacting a diamine component and a tetracarboxylic dianhydride component, and a soluble polyamidene obtained by imidization. The diamine component contains a diamine represented by the formula [1] and a diamine represented by the formula [2]; (where n is an integer from 0 to 19). The liquid crystal alignment treatment agent of claim 1, wherein the diamine represented by the formula [2] in the diamine component is 0.1 mol to 1.2 mol per mol of the diamine of the formula [1]. contain. The liquid crystal alignment treatment agent according to claim 1 or 2, wherein the diamine component contains 20 mol% or more of the diamine represented by the formula [1]. The liquid crystal alignment treatment agent according to claim 1 or 2, wherein the diamine component contains 5 to 60 mol% of the diamine represented by the formula [2]. The liquid crystal alignment treatment agent according to claim 1 or 2, wherein the positional relationship of the two amine groups of the diamine represented by the formula [1] and the diamine represented by the formula [2] is meta or Bit. For example, the liquid crystal alignment treatment agent of claim 1 of the patent scope, four of which The carboxylic acid dianhydride component contains a tetracarboxylic dianhydride having an alicyclic structure or an aliphatic structure. The liquid crystal alignment treatment agent of claim 6, wherein the tetracarboxylic dianhydride component contains an aromatic tetracarboxylic dianhydride. A liquid crystal alignment film obtained by applying a liquid crystal alignment treatment agent according to any one of claims 1 to 7 to an electrode-attached substrate, followed by firing and rubbing treatment. A liquid crystal display element characterized by using a liquid crystal alignment film according to item 8 of the patent application.