KR101589328B1 - Liquid crystal aligning agent and liquid crystal display element using same - Google Patents

Abstract

A liquid crystal alignment treatment agent which maintains good electric characteristics of the polyimide alignment film and has good whiteness and printability and does not cause aggregates that cause gap unevenness of the liquid crystal panel at the time of printing, a liquid crystal alignment film obtained using the liquid crystal alignment film, Lt; / RTI >
A resin component containing a polyimide obtained by imidizing a polyamic acid obtained by reacting a diamine component with a tetracarboxylic dianhydride and a resin component containing a polyimide obtained by reacting a resin component containing N-ethyl-2-pyrrolidone or N-cyclohexyl- A liquid crystal alignment treatment agent, a liquid crystal alignment film obtained by using the liquid crystal alignment treatment agent, and a liquid crystal display element.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a liquid crystal alignment treatment agent and a liquid crystal display element using the same,

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

A liquid crystal display element is a display element in which liquid crystal molecules are sandwiched between liquid crystal alignment films formed on a substrate and liquid crystal molecules aligned in a certain direction by a liquid crystal alignment film respond by voltage. This liquid crystal alignment film is generally produced by applying a so-called "rubbing treatment ", in which a surface of a polyimide film formed on a substrate on which electrodes are formed is rubbed by applying pressure to the surface thereof with rayon or nylon cloth. An alignment film for VA (abbreviation for vertical alignment) not subjected to rubbing treatment, and a photo alignment film for orienting a liquid crystal by applying anisotropy to the film surface by irradiating polarized UV.

As a means for forming the polyimide film on the substrate on which the electrode is formed, there can be used a method of preparing a coating film by using a solution of a polyimide precursor such as polyamic acid and imidizing the film on the substrate and a method of pre- There is a method of using a solution.

Among these methods, a method using a solution containing polyimide can form a polyimide film having excellent characteristics in the case of using a liquid crystal alignment film, even though baking at a relatively low temperature. On the other hand, the strength of the formed film is low, There is a problem in that scratches or peeling of the film may occur. Scratches or peeling of the surface of the liquid crystal alignment film are important problems because they cause display defects when the liquid crystal display device is used. In addition, since the polyimide generally has poor solubility in an organic solvent as compared with polyamic acid or the like, if it is imidized in advance, it may become difficult to form a uniform coating film. In addition, It may be insoluble and can not be contained in the liquid crystal alignment treatment agent. Therefore, the solubility of the polyimide contained in the liquid crystal alignment treatment agent is also important. Further, when a liquid crystal alignment treatment agent containing polyimide is used, in the case of printing on a substrate or the like, there is a problem that the varnish containing polyimide is whitened by moisture absorption or the varnish is dried on the printing plate to cause aggregation.

A liquid crystal alignment treatment agent containing a diamine component having a specific structure, which is excellent in the rubbing resistance of the liquid crystal alignment film and the solubility of the polyimide, has been proposed (see, for example, Patent Document 1). It has also been proposed to use N-vinylpyrrolidone or N-cyclohexylpyrrolidone in 50% or more of the solvent as a method for suppressing the whitening phenomenon of a varnish containing polyimide (see, for example, Patent See Document 2). However, a liquid crystal alignment treatment agent for suppressing the aggregation caused by drying the varnish has not been proposed so far.

Coagulation due to the drying of the varnish is characterized in that it occurs well at the edge of the printing plate. Therefore, even if some agglomerates are generated, there is no particular problem if they do not exist in the pixel. However, in recent years, in order to realize a high-speed response of a liquid crystal panel, a narrow gap of a panel is progressing. As described above, since the interval between the two substrates constituting the liquid crystal cell is narrowed, there has been an increase in the case where the aggregate as described above causes nonuniformity of the panel, which is not a problem if it is not present in the pixel.

International Publication No. 2006/126555 pamphlet Japanese Patent Application Laid-Open No. 5-117587

As a result of the studies by the present inventors, it has been found that the aggregate causing the unevenness of the gap of the panel occurs irrespective of the whitening phenomenon caused by moisture absorption of the varnish.

SUMMARY OF THE INVENTION In view of the above circumstances, it is an object of the present invention to provide a liquid crystal alignment treatment agent which is excellent in whiteness and printability and does not cause aggregates that cause gap unevenness of the liquid crystal panel at the time of printing, while maintaining good electrical properties of the polyimide alignment film The purpose is to provide. Further, in addition to the properties such as whiteness, printability, agglomerates, etc., the liquid crystal alignment treatment agent has excellent long-term storage stability. Further, when the liquid crystal alignment film is used as the liquid crystal alignment film, the rubbing resistance is excellent, the tilt angle of the liquid crystal is high, And also to provide a liquid crystal alignment treatment agent which is also excellent.

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have completed the present invention. That is, the present invention provides the following.

1. A resin composition comprising a polyimide-containing resin component obtained by imidizing a polyamic acid obtained by reacting a diamine component with a tetracarboxylic acid dianhydride, and a resin component containing a polyimide obtained by reacting a resin component containing N-ethyl-2-pyrrolidone or N-cyclohexyl- A liquid crystal alignment treatment agent characterized by containing a solvent component containing a pyrrolidone compound comprising at least one member selected from the group consisting of gold,

2. The liquid crystal alignment treating agent according to 1 above, wherein the pyrrolidone compound is N-ethyl-2-pyrrolidone and the N-ethyl-2-pyrrolidone is 5 to 80 mass% of the solvent component.

3. The liquid crystal alignment treatment agent according to 1 above, wherein the pyrrolidone compound is N-cyclohexyl-2-pyrrolidone and the N-cyclohexyl-2-pyrrolidone is 5 to 40 mass% of the solvent component.

4. The liquid crystal alignment treating agent according to any one of 1 to 3 above, wherein the resin component is contained in an amount of 1 to 10 mass% and the solvent component is contained in a content of 90 to 99 mass%.

5. The liquid crystal alignment treatment agent according to any one of 1 to 4 above, which contains a diaminobenzene having a disubstituted amino group substituted with an alkenyl group having 2 or 3 carbon atoms as a diamine component.

6. The liquid crystal alignment treating agent as described in 5 above, wherein the diaminobenzene having a disubstituted amino group substituted with an alkenyl group having 2 or 3 carbon atoms is a diamine represented by the following formula [1].

[Chemical Formula 1]

7. The liquid crystal alignment treating agent according to 6 above, wherein the diamine component further contains a diamine represented by the following formula.

(2)

(Wherein k represents an integer of 1 to 20)

8. The liquid crystal alignment treating agent according to 6 above, wherein the diamine represented by the formula [1] contains 20 to 90 mol% of the total diamine component.

9. The liquid crystal alignment treatment agent as described in 8 above, wherein the diamine represented by the formula [32] is contained in an amount of 5 to 40 mol% of the total diamine component.

10. A liquid crystal alignment film obtained by applying the liquid crystal alignment treatment agent described in any one of 1 to 9 above to a substrate on which an electrode is formed and baking.

11. A liquid crystal display element having the liquid crystal alignment layer according to the above 10.

According to the liquid crystal alignment treatment agent of the present invention, it is possible to obtain a liquid crystal alignment film having excellent electric characteristics and suppress generation of coagulated matter which causes gap unevenness of the liquid crystal panel at the time of printing, It can be produced with good production rate.

The present invention will be described in detail below.

The liquid crystal alignment treatment agent of the present invention is a treatment agent for forming a liquid crystal alignment film used in a liquid crystal display element and is a polyimide obtained by imidizing a polyamic acid obtained by reacting a diamine component with a tetracarboxylic acid dianhydride, - pyrrolidone or N-cyclohexyl-2-pyrrolidone. The structure of the polyimide used in the present invention is not particularly limited, but a diamine component containing a diaminobenzene having a disubstituted amino group substituted with an alkenyl group having 2 or 3 carbon atoms (hereinafter, referred to as a specific diamine) The use of a polyimide obtained by imidizing a polyamic acid obtained by reacting a bicarboxylic acid dianhydride component is particularly preferable because of its high solubility in an organic solvent.

[Diamine component]

The diamine component (also referred to simply as a diamine) used in the present invention is not particularly limited. The diamine can be used in a single species or plural species, and the kind is not limited. Examples of the diamine include alicyclic diamines, aromatic diamines, heterocyclic diamines or aliphatic diamines. Specific examples thereof are shown below.

Examples of the alicyclic diamine include 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, 4,4'-diaminodicyclohexylmethane, 4,4'-diamino-3,3'- Dimethyldicyclohexylamine, isophoronediamine, and the like.

Examples of the aromatic diamines include o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 2,4-diaminotoluene, 2,5-diaminotoluene, 3,5-diaminotoluene, , 4-diamino-2-methoxybenzene, 2,5-diamino-p-xylene, 1,3-diamino-4-chlorobenzene, 3,5-diaminobenzoic acid, Dichlorobenzene, 4,4'-diamino-1,2-diphenylethane, 4,4'-diamino-2,2'-dimethylbibenzyl, 4,4'-diaminodiphenyl Methane, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 2,2'-diaminostyrene Benzene, 4,4'-diaminostilbene, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfide, 4,4 ' Diaminodiphenylsulfone, 4,3'-diaminodiphenylsulfone, 4,4'-diaminobenzophenone, 1,3-bis (3-aminophenoxy) benzene, 1,3- Aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 3,5-bis Benzoic acid, 4,4'-bis (4-aminophenoxy) bibenzyl, 2,2-bis [ Bis [4- (4-aminophenoxy) phenyl] propane, bis [4- Bis (4-aminophenyl) phenyl] sulfone, 1,1-bis (4-aminophenyl) cyclohexane, 4-aminophenyl) fluorene, 2,2-bis (3-aminophenyl) hexafluoropropane, 2,2- , 2,4-diaminodiphenylamine, 1,8-diaminonaphthalene, 1,5-diaminonaphthalene, 1,5-diaminoanthraquinone, 1,3-diaminopyrrene, 1,6-diamino Pyrene, 1,8-diaminopyrene, 2,7-diaminofluorene, 1,3-bis (4-aminophenyl) tetramethyldisiloxane, benzidine, 2,2'-dimethylbenzidine, (4-aminophenyl) ethane, 1,3-bis (4- Bis (4-aminophenyl) pentane, 1,6-bis (4-aminophenyl) hexane, 1,7-bis Bis (4-aminophenyl) decane, 1,1-bis (4-aminophenyl) decane, Bis (4-aminophenoxy) pentane, 1,6-bis (4-aminophenoxy) Hexane, 1,7-bis (4-aminophenoxy) heptane, 1,8-bis (4-aminophenoxy) octane, (4-aminophenoxy) decane, di (4-aminophenyl) propane-1,3-dioate, , Di (4-aminophenyl) hexane-1,6-dioate, di (4-aminophenyl) heptane-1,7-dioate, di -Dioate, di (4-aminophenyl) nonane-1,9-dioate, di (4-aminophenyl) decane- Bis [4- (4-aminophenoxy) phenoxy] butane, 1,5-bis [4- (4-aminophenoxy) phenoxy] pentane, 1,6-bis [4- (4-aminophenoxy) phenoxy] Heptane, 1,8-bis [4- (4-aminophenoxy) phenoxy] octane, 1,9-bis [4- (4-aminophenoxy) phenoxy] decane, and the like.

Examples of the heterocyclic diamines include 2,6-diaminopyridine, 2,4-diaminopyridine, 2,4-diamino-1,3,5-triazine, 2,7-diaminodibenzofuran , 3,6-diaminocarbazole, 2,4-diamino-6-isopropyl-1,3,5-triazine, 2,5-bis (4-aminophenyl) And the like.

Examples of the aliphatic diamine include 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, Diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,3-diamino-2,2-dimethylpropane, 1,6- 2,5-dimethylhexane, 1,7-diamino-2,5-dimethylheptane, 1,7-diamino-4,4-dimethylheptane, 1,7-diamino- Diamino-5-methylheptane, 1,12-diaminododecane, 1,18-diaminooctadecane, 1,2-bis (3-aminopropoxy) ethane and the like.

In the present invention, as diamine, diaminobenzene having a disubstituted amino group substituted with an alkenyl group having 2 or 3 carbon atoms (hereinafter also referred to as a specific diamine) is preferably used in order to increase the solubility of the polyimide in an organic solvent . Particularly, a diaminobenzene having a disubstituted amino group substituted with a 2-propenyl group (hereinafter also referred to as an allyl group) represented by the following formula [1] is preferable.

(3)

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 between the two amino groups is preferably meta or para. A more preferable specific example of the diamine is given below.

[Chemical Formula 4]

Wherein the formula [2] is 2,4-diamino-N, N-diallylaniline and the formula [3] is 3,5-diamino-N, N-diallyaniline, 2,5-diamino-N, N-diallylaniline. The diaminobenzene is more preferably at least one selected from the group consisting of the above-mentioned [2], [3] and [4]. Among them, the diaminobenzene is particularly preferably 2,4-diamino-N, N-diallylamine.

In the present invention, the diamine component to be a raw material of the polyimide may be only a specific diamine, or may be a combination of one or more of a specific diamine and other diamines. By containing a specific diamine in the diamine component for obtaining the polyimide, the solubility of the polyimide in the organic solvent is enhanced. In addition, problems such as scratches and film peeling on the film surface when the coating film is rubbed are improved.

The content of the specific diamine in the diamine component is preferably 20 mol% or more, more preferably 40 mol% or more, and particularly preferably 50 mol% or more. The higher the specific diamine content ratio in the diamine component is, the higher the effect of suppressing scratches on the surface of the alignment film during the rubbing treatment and peeling of the film is enhanced. In addition, the solubility of the obtained polyimide in an organic solvent becomes high. On the other hand, the diamine component may be only a specific diamine, but it is preferable to use a diamine other than the specific diamine in combination to impart other properties required for the liquid crystal alignment film. Therefore, the content of the specific diamine is more preferably 90 mol% or less. Particularly, when a specific diamine, 4-aminobenzylamine, 3-aminobenzylamine or 4-aminophenetylamine is used, the solubility of the polyimide in an organic solvent becomes high and a liquid crystal alignment treatment agent having excellent liquid crystal alignability can be obtained . The preferable content of 4-aminobenzylamine, 3-aminobenzylamine or 4-aminophenetylamine in the diamine component is 10 mol% to 50 mol%.

Further, in order to increase the pretilt angle of the liquid crystal, diamines having a specific substituent may be used in combination. As the substituent capable of increasing the pretilt angle of the liquid crystal, a long-chain alkyl group, a perfluoroalkyl group, an aromatic cyclic group, an aliphatic cyclic group, a substituent group combining these groups, or a steroid skeleton group is preferable. Specific examples of the diamine having such a substituent include, but are not limited to, the following. In the structures exemplified below, j represents an integer of 5 to 20, preferably 9 to 17, and k represents an integer of 1 to 20, preferably 4 to 15.

[Chemical Formula 5]

[Chemical Formula 6]

(7)

[Chemical Formula 8]

Of the above diamines, the diamines of the formulas [5] and [32] are preferred because of their excellent liquid crystal alignability. The diamines of the formulas [12] to [19] are preferably used for an alignment film for OCB (Optically Compensated Bend) and an alignment film for VA (Vertical Alignment) As a preferable example, the diamine of the formula [5] or [32] is contained in the diamine component in an amount of 5 to 40 mol%, preferably 10 to 30 mol%, in the TN (Twisted Nematic) (10 to 90 °) for OCB and VA, the diamines of the formulas [12] to [19] may be contained in the diamine component in an amount of 5 to 60 mol%, preferably 10 to 40 mol% It is not limited.

Among the aforementioned diamines, particularly, the diamine of the formula [32] is preferable because it has a high tilt angle and is used in combination with the specific diamine, even when the rubbing condition is weak, since the liquid crystal alignability is excellent. In addition, the effect of increasing the pretilt angle of the liquid crystal by the diamine as described above tends to be weakened when the liquid crystal alignment treatment agent contains a large amount of N-ethyl-2-pyrrolidone or N-cyclohexyl-2-pyrrolidone , And the diamine of the formula [32] are characterized by the fact that they are not easily affected by such effects, and are preferable as the diamine component of the polyimide contained in the liquid crystal alignment treatment agent of the present invention.

[Component of tetracarboxylic acid dianhydride]

In the present invention, the tetracarboxylic acid dianhydride component serving as the raw material of the polyimide may be one kind of tetracarboxylic acid dianhydride, or two or more kinds of tetracarboxylic acid dianhydrides may be mixed and used.

However, in view of the fact that a polyimide having a high imidization ratio can be easily obtained with a polyimide having a relatively high solubility and a high voltage holding ratio of the liquid crystal cell can be increased, tetracarboxylic acid dianhydride having an alicyclic structure or aliphatic structure is used .

Examples of the tetracarboxylic acid dianhydride having an alicyclic or aliphatic structure include 1,2,3,4-cyclobutane tetracarboxylic acid dianhydride, 1,2-dimethyl-1,2,3,4-cyclobutane Tetracarboxylic acid dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic acid dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclo Butane tetracarboxylic acid dianhydride, 1,2,3,4-cyclopentanetetracarboxylic acid dianhydride, 2,3,4,5-tetrahydrofuran tetracarboxylic acid dianhydride, 1,2,4,5 -Cyclohexanetetracarboxylic acid dianhydride, 3,4-dicarboxy-1-cyclohexylsuccinic dianhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic dianhydride, 1,2,3,4-butanetetracarboxylic acid dianhydride, bicyclo [3,3,0] octane-2,4,6,8-tetracarboxylic acid dianhydride, 3,3 ', 4,4 '-Dicyclohexyltetracarboxylic acid dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, cis-3,7- Butyl-1,5-diene-cyclooctadiene -1,2,5,6-tetracarboxylic acid dianhydride, tricyclo [4.2.1.0 ^2,5] nonane -3,4,7,8- tetrahydro-carboxylic acid - 3,4: 7,8-2 anhydride, hexahydro cyclo ^{[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, 12-2 anhydride and the like.

As the tetracarboxylic acid dianhydride having an alicyclic structure or an aliphatic structure, 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 3,4-dicarboxy-1,2,3,4- Use of tetrahydro-1-naphthalenesuccinic dianhydride or 1,2,3,4-butanetetracarboxylic acid dianhydride is particularly preferable because an alignment film excellent in liquid crystal alignability can be obtained.

In addition to the tetracarboxylic acid dianhydride having an alicyclic structure or aliphatic structure, the aromatic tetracarboxylic acid dianhydride is preferably used in combination because it can improve the liquid crystal alignability and reduce the accumulated charge of the liquid crystal cell . Examples of the aromatic tetracarboxylic acid dianhydride include pyromellitic dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic acid dianhydride, 2,2', 3,3'-biphenyltetracarboxylic acid Biphenyltetracarboxylic acid dianhydride, 3,3 ', 4,4'-benzophenonetetracarboxylic acid dianhydride, 2,3,3', 4- Benzophenone tetracarboxylic acid dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, bis (3,4-dicarboxyphenyl) sulfone dianhydride, 1,2,5,6-naphthalenetetracarboxylic acid 2-anhydride, 2,3,6,7-naphthalenetetracarboxylic acid dianhydride, and the like.

Examples of the aromatic tetracarboxylic acid dianhydride include pyromellitic dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride , Or 1,4,5,8-naphthalenetetracarboxylic acid dianhydride are particularly preferable.

The ratio of the tetracarboxylic acid dianhydride having an alicyclic structure or the aliphatic structure to the aromatic tetracarboxylic acid dianhydride is preferably in the range of from 0.1 to 5 mol, Preferably 90/10 to 50/50, and more preferably 80/20 to 60/40 in terms of the former / the latter molar ratio.

[Polyimide and production method thereof]

The polyimide used in the liquid crystal alignment treatment agent of the present invention is a polyimide obtained by imidizing a polyamic acid obtained by reacting the diamine component and the tetracarboxylic acid dianhydride component. Here, the polyamic acid can be obtained by mixing the tetracarboxylic acid dianhydride component and the diamine component in an organic solvent and reacting.

As a method for mixing the tetracarboxylic acid dianhydride component and the diamine component in an organic solvent, a method in which a solution prepared by dispersing or dissolving a diamine component in an organic solvent is stirred and the tetracarboxylic acid dianhydride component is dispersed in the organic solvent A method in which a diamine component is added to a solution in which a tetracarboxylic acid dianhydride component is dispersed or dissolved in an organic solvent, a method in which a tetracarboxylic acid dianhydride component and a diamine component are alternately added, and the like . When the tetracarboxylic acid dianhydride component or the diamine component is composed of a plurality of compounds, the plural kinds of components may be polymerized in advance in the mixed state, or they may be subjected to sequential polymerization reaction separately.

The temperature at which the tetracarboxylic acid dianhydride component and the diamine component are polymerized in an organic solvent is usually 0 to 150 ° C, preferably 5 to 100 ° C, more preferably 10 to 80 ° C. When the temperature is higher, the polymerization reaction is terminated quickly. However, when the temperature is too high, a polymer having a high molecular weight may not be obtained.

If the concentration is excessively low, it becomes difficult to obtain a polymer having a high molecular weight. If the concentration is too high, the viscosity of the reaction liquid becomes excessively high and it becomes difficult to carry out uniform stirring. Therefore, The concentration of the total amount of the carboxylic acid dianhydride component and the diamine component is preferably 1 to 50 mass%, more preferably 5 to 30 mass%. The initial stage of the polymerization reaction may be carried out at a high concentration, and then an organic solvent may be added.

The organic solvent to be used in the reaction is not particularly limited as long as the resulting polyamic acid dissolves, but it is preferable that the organic liquid crystal aligning agent is N-ethyl-2-pyrrolidone or N-cyclohexyl- , Or other solvent may be used. Specific examples thereof include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, dimethylsulfoxide, tetramethylurea, pyridine, dimethylsulfone , Hexamethyl sulfoxide,? -Butyrolactone, and 1,3-dimethylimidazolidinone. These may be used alone or in combination. The polyamic acid may be a solvent that does not dissolve the polyamic acid, or may be mixed with the solvent in the range that does not precipitate the produced polyamic acid. In addition, since moisture in the organic solvent inhibits the polymerization reaction and further causes hydrolysis of the resulting polyamic acid, it is preferable to use an organic solvent that is dehydrated and dried as much as possible.

The ratio of the tetracarboxylic acid dianhydride component to the diamine component used in the polymerization reaction of the polyamic acid is preferably 1: 0.8 to 1: 1.2 in terms of the molar ratio, and the molecular weights of the polyamic acid Lt; / RTI > By controlling the molecular weight of the polyamic acid, the molecular weight of the polyimide obtained after imidation can be adjusted.

The molecular weight of the polyimide contained in the liquid crystal alignment treatment agent of the present invention is not particularly limited but is preferably 2,000 to 200,000 in weight average molecular weight and more preferably 5,000 to 200,000 in terms of the strength of the coating film and ease of handling as a liquid crystal alignment treatment agent. ~ 50,000.

The imidization of the polyamic acid thus obtained can be carried out by stirring 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, trioctylamine, and the like. Among them, pyridine is preferred since it has a basicity suitable for proceeding the reaction. Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, and pyromellitic anhydride. Among them, acetic anhydride is preferable because the obtained polyimide can be easily purified after completion of imidization. As the organic solvent, a solvent used in the above-mentioned polyamic acid polymerization reaction can be used.

The imidization rate of polyimide can be controlled by controlling the amount of catalyst, reaction temperature, and reaction time. The amount of the basic catalyst at this time is preferably 0.2 to 10 times, more preferably 0.5 to 5 times, the molar amount of the amic acid group of the raw material polyamic acid. The amount of the acid anhydride is preferably 1 to 30 times, more preferably 1 to 10 times, the molar amount of the amic acid group of the raw material polyamic acid. The reaction temperature is preferably -20 to 250 占 폚, more preferably 0 to 180 占 폚.

The imidization rate of the polyimide contained in the liquid crystal alignment treatment agent of the present invention is not particularly limited, but it is preferably 40% or more in view of electrical characteristics, more preferably 60% or more, more preferably 60% Is more than 80%.

Since the added catalyst remains in the polyimide solution thus obtained, it is preferable that the polyimide is recovered and washed and then used in the liquid crystal alignment treatment agent of the present invention.

The recovery of the polyimide can be carried out by introducing the imidized solution into a stirring solvent which has been stirred and then filtering out the precipitated polyimide. Examples of the poor solvent include methanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene and the like. The recovered polyimide can be cleaned with this poor solvent.

The polyimide thus recovered and washed can be converted into a powder at normal temperature or under reduced pressure by heating or drying at room temperature.

[Liquid crystal alignment treatment agent]

The liquid crystal alignment treatment agent of the present invention is a solution containing the polyimide as a resin component and containing N-ethyl-2-pyrrolidone or N-cyclohexyl-2-pyrrolidone as a solvent component. In the present invention, it is necessary to use N-ethyl-2-pyrrolidone or N-cyclohexyl-2-pyrrolidone as a solvent component, and also in a pyrrolidone compound, -Pyrrolidone is used, whitening of the coating film and unevenness of the film thickness near the printing edge may occur as in the later comparative example, and it is difficult to achieve the object of the present invention.

The concentration of the solution constituting the liquid crystal alignment treatment agent can be appropriately changed according to the setting of the thickness of the liquid crystal alignment film to be formed. The amount of the solvent component is preferably 9 to 99 parts by mass relative to 1 part by mass of the nonvolatile component such as a resin component, And preferably 11.5 to 49 parts by mass. If the amount of the solvent component is more than 99 parts by mass, it is difficult to form a uniform and defect-free coating film, and if it is less than 9 parts by mass, the storage stability of the solution may be deteriorated. The content of the solvent component in the liquid crystal alignment treatment agent of the present invention is preferably 90 to 99% by mass, and more preferably 92 to 98% by mass, of the entire liquid crystal alignment treatment agent.

The resin component in the liquid crystal alignment treatment agent of the present invention may be a mixture of two or more kinds of polyimides having different structures. In addition, polyamic acid or other kinds of resins may be used in combination so as not to impair the electrical properties, to reduce the storage stability of the varnish, and to prevent aggregation that causes gap unevenness of the liquid crystal panel during printing . The amount of such a resin to be used in combination is preferably from 0.05 to 7 parts by mass, more preferably from 0.1 to 4 parts by mass, based on 1 part by mass of the polyimide. The preferred content of the resin component in the liquid crystal alignment treatment agent of the present invention is preferably 1 to 10 mass%, more preferably 2 to 8 mass%, of the liquid crystal alignment treatment agent as a whole.

Although the solvent component in the liquid crystal alignment treatment agent of the present invention may be only N-ethyl-2-pyrrolidone, it is preferable that other solvent is contained to control the solubility of the resin component and the coating property on the substrate. On the other hand, in the case of N-cyclohexyl-2-pyrrolidone, since the solubility of the polyimide is lower than that of N-ethyl-2-pyrrolidone, It is preferable that the content of the solvent is 40% by mass or less of the total components, and the other solvent component contains a solvent for securing solubility of the resin component.

Examples of the solvent for securing solubility of the resin component include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, 2- -Vinylpyrrolidone, dimethylsulfoxide, tetramethylurea, dimethylsulfone, hexamethylsulfoxide,? -Butyrolactone, and 1,3-dimethyl-imidazolidinone. Among them, N-methyl-2-pyrrolidone, 1,3-dimethylimidazolidinone and? -Butyrolactone are preferably used since they have high solubility of polyimide. The? -Butyrolactone is preferably used because it has an effect of inhibiting whitening.

As the solvent for controlling the coating property on the substrate, a solvent having a low surface tension may be mentioned. By appropriately mixing a solvent having a low surface tension with a solvent component, it is possible to improve the uniformity of the coating film upon application to a substrate.

Examples of the solvent having a low surface tension include ethyl cellosolve, butyl cellosolve, ethyl carbitol, butyl carbitol, ethyl carbitol acetate, ethylene glycol, 1-methoxy-2-propanol, 1- Propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanol, diethylene glycol diethyl ether, propylene glycol monoacetate, propylene glycol diacetate, dipropylene glycol monomethyl ether, propylene glycol- Propanol, lactic acid methyl ester, lactic acid ethyl ester, lactic acid n-propyl ester (2-ethoxypropoxy) propanol, , N-butyl lactate, and lactic acid isoamyl ester. Of these, butyl cellosolve, ethyl carbitol, dipropylene glycol monomethyl ether, and diethylene glycol diethyl ether are particularly preferred from the viewpoint of coatability on a substrate.

When the other solvent is contained in the solvent component, the amount of N-ethyl-2-pyrrolidone or N-cyclohexyl-2-pyrrolidone is preferably 0.5 part by mass or more based on 1 part by mass of the resin component. And preferably 1 part by weight or more and 80 parts by weight or less, and more preferably 2 parts by weight or more and 70 parts by weight or less. In particular, N-ethyl-2-pyrrolidone is used preferably because it has excellent storage stability of the varnish because of excellent solubility of the resin component and does not cause whitening of the varnish even when absorbing moisture. In the present invention, the content of N-ethyl-2-pyrrolidone is preferably from 5 to 80% by mass, more preferably from 10 to 70% by mass, based on the entire solvent components. On the other hand, the content of N-cyclohexyl-2-pyrrolidone is preferably 5 to 40% by mass, more preferably 10 to 30% by mass, based on the entire solvent component. In addition, as described above, it is preferable to set N-ethyl-2-pyrrolidone to not more than 40% by mass of the total solvent components provided that the effect of increasing the pretilt angle of the liquid crystals is not weakened.

The content of the solvent for ensuring the solubility of the resin component is preferably 80% by mass or less, more preferably 60% by mass or less, more preferably 80% by mass or less of the solvent component, % Or less. The solvent having a low surface tension improves the coatability of the substrate. However, if the amount is too large, precipitation of the resin component will occur. Therefore, the content is preferably 60% by mass or less, more preferably 50% Or less. When a solvent for securing the solubility of the resin component is used in combination with a solvent having a low surface tension, the more preferred content of each solvent is 5 to 70% by mass of the solvent for securing solubility of the resin component, Is 10 to 60% by mass, more preferably 10 to 45% by mass for securing the solubility of the resin component, and 20 to 50% by mass for the solvent having a low surface tension.

Examples of the solvent composition of the liquid crystal alignment treatment agent of the present invention include 5 to 80% by mass of N-ethyl-2-pyrrolidone, 5 to 70% by mass of solvent for securing solubility of the resin component, A mixed solvent having 10 to 60 mass% of a solvent having a tensile strength; A mixed solvent of 10 to 70% by mass of N-ethyl-2-pyrrolidone, 10 to 45% by mass of a solvent for securing the solubility of the resin component, and 20 to 50% by mass of a solvent having a low surface tension; A mixed solvent of 5 to 40% by mass of N-ethyl-2-pyrrolidone, 5 to 70% by mass of a solvent for securing solubility of the resin component, and 10 to 60% by mass of a solvent having a low surface tension; A mixed solvent of 10 to 40 mass% of N-ethyl-2-pyrrolidone, 10 to 45 mass% of a solvent for securing the solubility of the resin component, and 20 to 50 mass% of a solvent having a low surface tension; A mixed solvent having 5 to 40 mass% of N-cyclohexyl-2-pyrrolidone, 5 to 70 mass% of a solvent for securing the solubility of the resin component, and 10 to 60 mass% of a solvent having a low surface tension; 10 to 40 mass% of N-cyclohexyl-2-pyrrolidone, 10 to 45 mass% of a solvent for securing solubility of a resin component, and 20 to 50 mass% of a solvent having a low surface tension can do.

The liquid crystal alignment treatment agent of the present invention may contain an additive for improving the properties of the coating film in addition to the above.

Examples of the additives for improving the properties of the coating film include 3-aminopropylmethyldiethoxysilane, 3-phenylaminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, (aminoethylaminomethyl) phenethyltrimethoxysilane And the like. By the addition of these silane coupling agents, the adhesion of the coating film to the substrate can be further improved, but if added too much, the polyimide used in the present invention and the polymer compound used in combination with it may cause coagulation. Therefore, the content of the silane coupling agent is preferably 0.1 to 20 parts by mass, more preferably 0.2 to 10 parts by mass based on 100 parts by mass of the resin component used in the present invention.

[Method of preparing liquid crystal alignment treatment agent]

The method of preparing the liquid crystal alignment treatment agent of the present invention is not particularly limited as long as the components contained therein are uniform in the liquid crystal alignment treatment agent. For example, the polyimide powder may be dissolved in an organic solvent to form a polyimide solution, and then an organic solvent may be added to a desired concentration to dilute the polyimide solution. In this dilution step, adjustment of the solvent composition for controlling the coating property on the substrate and addition of additives for improving the properties of the coating film can be carried out. Examples of the solvent for dissolving the polyimide powder include N-ethyl-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone or the above-mentioned solvents. The liquid crystal alignment treatment agent thus obtained is preferably filtered before it is applied to the substrate.

The liquid crystal alignment treatment agent of the present invention can be used as a coating film by applying it on a substrate, followed by drying and firing, and rubbing treatment of the coated film surface is used as a liquid crystal alignment film for rubbing. It is also used as a VA liquid crystal alignment film or a photo alignment film which does not undergo 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 glass substrate, a plastic substrate such as an acrylic substrate or a polycarbonate substrate, or the like can be used and a substrate on which an ITO electrode for liquid crystal driving is formed is used Is preferable from the viewpoint of simplification of the process. In the reflection type liquid crystal display device, an opaque material such as a silicon wafer can be used only for a substrate on one side. In this case, a material for reflecting light such as aluminum can also be used as the electrode in this case.

As a method for applying the liquid crystal alignment treatment agent, a spin coating method, a printing method, an ink jet method, or the like can be mentioned. In view of productivity, the flexographic printing method is widely used industrially and the liquid crystal alignment treatment agent Lt; / RTI >

The drying step after applying the liquid crystal alignment treatment agent is not necessarily required. However, when the time from the application to the firing is not constant for each substrate or when the firing is not performed immediately after the application, it is preferable to include a drying step. The drying is not particularly limited as long as the solvent is evaporated to such an extent that the shape of the coated film is not deformed by transporting the substrate or the like. Specifically, for example, a method of drying on a hot plate at 50 to 150 ° C, preferably 80 to 120 ° C, for 0.5 to 30 minutes, preferably 1 to 5 minutes may be mentioned.

The substrate to which the liquid crystal alignment treatment agent is applied can be baked at any temperature of 100 to 350 캜, preferably 150 to 300 캜, and more preferably 180 to 250 캜. When an amic acid group is present in the liquid crystal alignment treatment agent, the amide acid is changed to an imide according to the firing temperature, but the liquid crystal alignment treatment agent of the present invention does not necessarily need to be imidized to 100%.

The thickness of the coated film after firing is disadvantageous from the viewpoint of power consumption of the liquid crystal display element if it is excessively large and from 10 to 200 nm, 100 nm.

Conventional rubbing apparatuses can be used for the rubbing treatment of the coating film surface formed on the substrate as described above. Examples of the material of the rubbing cloth at this time include cotton, rayon, nylon and the like.

In the liquid crystal display element of the present invention, a substrate on which a liquid crystal alignment film is formed from the liquid crystal alignment treatment agent of the present invention is obtained by the above-described technique, and then a liquid crystal cell is produced by a known method to form a liquid crystal display element. One example of the production of a liquid crystal cell is a method in which a pair of substrates on which a liquid crystal alignment film is formed is heated at a temperature in the range of 0 to 270 占 preferably between 1 and 30 占 퐉, more preferably between 2 and 10 占 퐉, There is a general method in which the liquid crystal is sealed at an arbitrary angle, the periphery is fixed with a sealant, and a liquid crystal is injected and sealed. The method of sealing the liquid crystal is not particularly limited, and examples thereof include a vacuum method in which liquid crystal is injected after reducing the pressure in the produced liquid crystal cell, and a dropping method in which a liquid crystal is dropped and sealed.

The liquid crystal display element thus obtained can be applied to a display element by various methods such as a TN liquid crystal display element, a STN liquid crystal display element, a TFT liquid crystal display element, an OCB liquid crystal display element, further, a transverse electric field liquid crystal display element, Is preferably used.

Example

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not construed as being limited thereto.

The abbreviations used in Examples and Comparative Examples are as follows.

≪ Tetracarboxylic acid dianhydride >

CBDA: 1,2,3,4-Cyclobutane tetracarboxylic acid dianhydride

PMDA: pyromellitic acid dianhydride

TDA: 3,4-Dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic acid dianhydride

<Diamine>

2,4-DAA: 2,4-diamino-N, N-diallylamine

[Chemical Formula 9]

p-PDA: p-phenylenediamine

DDM: 4,4'-diaminodiphenylmethane

BAPP: 1,5-bis (4-aminophenoxy) pentane

C12DAB: 4-Dodecyloxy-1,3-diaminobenzene

C14DAB: 4-tetradecyloxy-1,3-diaminobenzene

C18DAB: 4-octadecyloxy-1,3-diaminobenzene

PCBA-PDA: 4- (t-4-pentylcyclohexyl) benzamide-2 ', 4'-phenylenediamine

[Chemical formula 10]

3-ABA: 3-aminobenzylamine

<Organic solvent>

NMP: N-methyl-2-pyrrolidone

NEP: N-ethyl-2-pyrrolidone

NCP: N-cyclohexyl-2-pyrrolidone

? BL:? -butyrolactone

DMI: 1,3-dimethylimidazolidinone

BC: butyl cellosolve

DPM: dipropylene glycol monomethyl ether

EC: Ethyl Carbitol

&Lt; Measurement of molecular weight &

The molecular weight of the polyimide was measured by a GPC (room temperature gel permeation chromatography) apparatus and the number average molecular weight and the weight average molecular weight were calculated as polyethylene glycol and polyethylene oxide conversion values.

GPC apparatus: manufactured by Shodex Corp. (GPC-101)

Column: manufactured by Shodex Co., Ltd. (serial of KD803, KD805)

Column temperature: 50 ° C

Eluent: N, N-dimethylformamide (30 m mol / l of lithium bromide-hydrate (LiBr.H ₂ O) as additive, 30 mmol / l of phosphoric acid anhydrous crystal (o-phosphoric acid) (THF) of 10 ml / l)

Flow rate: 1.0 ml / min

Standard sample for preparing a calibration curve: TSK standard polyethylene oxide (weight average molecular weight: about 900,000, 150,000, 100,000, 30,000) manufactured by Tosoh Corporation and polyethylene glycol (weight average molecular weight: about 12,000, 4,000, 1,000) manufactured by Polymer Laboratories.

&Lt; Measurement of imidization rate &

The imidization rate of the polyimide was measured as follows. 20 mg of the polyimide powder was placed in an NMR sample tube, and 0.53 ml of deuterated dimethyl sulfoxide (DMSO-d ₆ , 0.05% TMS mixture) was added to dissolve it completely. This solution was subjected to proton NMR measurement at 500 MHz using an NMR measuring instrument (JNM-ECA500) manufactured by Nippon Densu. The proton derived from the structure in which the imidation rate is not changed before and after imidization is determined as the reference proton and the peak integrated value of the proton and the proton peak integrated value derived from the NH group of the amic acid appearing in the vicinity of 9.5 to 10.0 ppm Was obtained by the following equation.

Imidization ratio (%) = (1 -? X / y) x 100

In the above equation, x is the proton peak integration value derived from the NH group of amic acid, y is the peak integrated value of the reference proton, and? Is the NH group of the amic acid when the polyamic acid (imidization ratio is 0%) The ratio of the number of reference protons to one proton.

(Synthesis Example 1)

(0.030 mol) of CBDA and 6.54 g (0.030 mol) of PMDA as a tetracarboxylic acid dianhydride component, 6.10 g (0.030 mol) of 2,4-DAA as a diamine component and 4.89 g ㏖), and 9.62 g (0.030 mol) of C14 DAB were reacted in 162.7 g of NMP at 23 캜 for 24 hours to obtain a polyamic acid solution.

To 142.8 g of the polyamic acid solution, 333.2 g of NMP was added and diluted. 21.5 g of acetic anhydride and 9.2 g of pyridine were added, and the mixture was reacted at 50 ° C for 3 hours to imidize.

The reaction solution was cooled to room temperature, and then charged into 1.8 L of methanol to recover the precipitated solid. Further, this solid was washed with methanol several times, and then dried under reduced pressure at a temperature of 100 占 폚 to obtain a white powder of polyimide (SPI). This polyimide had a number average molecular weight of 13,472 and a weight average molecular weight of 35,859. The imidization ratio was 89%.

(Synthesis Example 2)

131.3 g of? BL was added to 17.9 g of the polyimide obtained in the same manner as in Synthesis Example 1, and the mixture was stirred at a temperature of 50 占 폚 for 24 hours. At the end of the stirring, the polyimide was completely dissolved.

(Synthesis Example 3)

14.4 g of NEP was added to 1.6 g of the polyimide obtained in the same manner as in Synthesis Example 1, and the mixture was stirred at a temperature of 50 占 폚 for 24 hours. At the end of the stirring, the polyimide was completely dissolved.

(Synthesis Example 4)

14.4 g of NMP was added to 1.6 g of the polyimide obtained in Synthesis Example 1, and the mixture was stirred at a temperature of 50 占 폚 for 24 hours. At the end of the stirring, the polyimide was completely dissolved.

(Synthesis Example 5)

8 g of? BL and 6.4 g of NCP were added to 1.6 g of the polyimide obtained in Synthesis Example 1, and the mixture was stirred at a temperature of 50 占 폚 for 24 hours. At the end of the stirring, the polyimide was completely dissolved.

(Synthesis Example 6)

13.53 g (0.069 mol) of CBDA and 6.54 g (0.030 mol) of PMDA as a tetracarboxylic acid dianhydride component, 7.12 g (0.035 mol) of 2,4-DAA as a diamine component, 4.89 g (0.040 mol) and 10.19 g (0.025 mol) of PCBA-PDA were reacted in 169.1 g of NMP at 23 DEG C for 24 hours to obtain a polyamic acid solution.

To 150 g of the polyamic acid solution, 350 g of NMP was added and diluted. 21.74 g of acetic anhydride and 9.27 g of pyridine were added, and the mixture was allowed to react at a temperature of 50 캜 for 3 hours to be imidized.

The reaction solution was cooled to room temperature, and then charged into 1.86 L of methanol to recover the precipitated solid. Further, this solid was washed with methanol several times, and then dried under reduced pressure at a temperature of 100 占 폚 to obtain a white powder of polyimide (SPI). The polyimide had a number average molecular weight of 12,156 and a weight average molecular weight of 32,418. The imidization rate was 90%.

(Synthesis Example 7)

35.2 g of? BL was added to 4.8 g of the polyimide obtained in the same manner as in Synthesis Example 6, and the mixture was stirred at a temperature of 50 占 폚 for 24 hours. At the end of the stirring, the polyimide was completely dissolved.

(Synthesis Example 8)

As the tetracarboxylic acid dianhydride component, 15.01 g (0.05 mol) of TDA and 4.87 g (0.045 mol) of p-PDA were used as the diamine component, and 1.88 g (0.005 mol) Lt; 0 &gt; C for 24 hours to obtain a polyamic acid solution.

To this polyamic acid solution, 350 g of NMP was added and diluted, and 51.0 g of acetic anhydride and 23.7 g of pyridine were added, and the reaction was carried out at 40 ° C for 3 hours to imidize.

The reaction solution was cooled to room temperature, and then charged into 1.7 L of methanol to recover the precipitated solid matter. Further, this solid was washed with methanol several times, and then dried under reduced pressure at a temperature of 100 占 폚 to obtain a white powder of polyimide (SPI). This polyimide had a number average molecular weight of 9,273 and a weight average molecular weight of 18,815. The imidization rate was 84%.

(Synthesis Example 9)

94.0 g of NEP was added to 6.0 g of the polyimide obtained in the same manner as in Synthesis Example 8, and the mixture was stirred at a temperature of 50 캜 for 24 hours. At the end of the stirring, the polyimide was completely dissolved.

(Synthesis Example 10)

, 4.90 g (0.025 mol) of CBDA as a tetracarboxylic acid dianhydride component, 4.80 g (0.022 mol) of PMDA and 9.91 g (0.05 mol) of DDM as a diamine component were dissolved in a mixed solvent of 55.5 g of NEP and 55.5 g of? And reacted at room temperature for 5 hours to obtain a polyamic acid solution. The polyamic acid had a number average molecular weight of 11,067 and a weight average molecular weight of 26,270.

(Synthesis Example 11)

NEP and BC were added to 50 g of the polyamic acid solution obtained in Synthesis Example 10 to prepare a solution containing 6 mass% of polyamic acid, 59 mass% of NEP, 20 mass% of? -BL and 15 mass% of BC.

(Synthesis Example 12)

PDA as a diamine component, 2.70 g (0.025 mol) of p-PDA and 3.05 g (0.015 mol) of 2,4-DAA as PCA-PDA as the tetracarboxylic acid dianhydride component and 15.01 g 4.08 g (0.01 mol) of NMP were reacted in 140.8 g of NMP at 50 DEG C for 24 hours to obtain a polyamic acid solution.

To this polyamic acid solution, 331 g of NMP was added and diluted, and acetic anhydride (51.0 g) and pyridine (23.7 g) were added and reacted at 40 ° C for 3 hours for imidization.

The reaction solution was cooled to room temperature, and then poured into 2.0 L of methanol to recover the precipitated solid matter. Further, this solid was washed with methanol several times, and then dried under reduced pressure at a temperature of 100 占 폚 to obtain a white powder of polyimide (SPI). The polyimide had a number average molecular weight of 8,579 and a weight average molecular weight of 22,319. The imidization rate was 87%.

(Synthesis Example 13)

94.0 g of? BL was added to 6.0 g of polyimide obtained in the same manner as in Synthesis Example 12, and the mixture was stirred at a temperature of 50 占 폚 for 24 hours. At the end of the stirring, the polyimide was completely dissolved.

(Synthesis Example 14)

? BL and BC were added to 50 g of the polyamic acid solution obtained in Synthesis Example 10 to prepare 6 mass% of polyamic acid, 59 mass% of? BL, 20 mass% of NEP and 15 mass% of BC.

(Synthesis Example 15)

, 19.41 g (0.099 mol) of CBDA as a tetracarboxylic acid dianhydride component, 5.73 g (0.02 mol) of BAPP as a diamine component, 14.23 g (0.07 mol) of 2,4-DAA and 4.08 g ㏖), and reacted in 246.2 g of NMP at 23 캜 for 24 hours to obtain a polyamic acid solution.

To this polyamic acid solution, 434 g of NMP was added and diluted. 25.8 g of acetic anhydride and 11.0 g of pyridine were added, and the mixture was reacted at 35 ° C for 3 hours to imidize.

The reaction solution was cooled to room temperature, and then charged into 2.7 L of methanol to recover the precipitated solid matter. Further, this solid was washed with methanol several times, and then dried under reduced pressure at a temperature of 100 占 폚 to obtain a white powder of polyimide (SPI). The polyimide had a number average molecular weight of 12,132 and a weight average molecular weight of 26,538. The imidization rate was 70%.

(Synthesis Example 16)

108.0 g of NEP was added to 12.0 g of the polyimide obtained in the same manner as in Synthesis Example 15, and the mixture was stirred at a temperature of 50 占 폚 for 24 hours. At the end of the stirring, the polyimide was completely dissolved.

(Synthesis Example 17)

As the tetracarboxylic acid dianhydride component, 19.41 g (0.099 mol) of CBDA, 14.23 g (0.07 mol) of 2,4-DAA and 8.77 g (0.03 mol) of C12 DAB were used as the diamine component. , And reacted at 23 DEG C for 24 hours to obtain a polyamic acid solution.

To this polyamic acid solution, 494.9 g of NMP was added and diluted. 30.6 g of acetic anhydride and 13.1 g of pyridine were added, and the mixture was allowed to react at a temperature of 50 ° C for 3 hours to be imidized.

The reaction solution was cooled to room temperature, and then charged into 2.6 L of methanol to recover the precipitated solid. Further, this solid was washed with methanol several times, and then dried under reduced pressure at a temperature of 100 占 폚 to obtain a white powder of polyimide (SPI). This polyimide had a number average molecular weight of 11,098 and a weight average molecular weight of 21,431. The imidization rate was 91%.

(Synthesis Example 18)

14.4 g of NEP was added to 1.6 g of the polyimide obtained in the same manner as in Synthesis Example 17, and the mixture was stirred at a temperature of 50 캜 for 24 hours. At the end of the stirring, the polyimide was completely dissolved.

(Example 1)

20.23 g of the solution obtained in the same manner as in Synthesis Example 2 was cooled to 23 占 폚, 8.67 g of? BL, 4.93 g of NEP and 14.78 g of BC were added and the mixture was stirred at a temperature of 50 占 폚 for 20 hours. After completion of the stirring, the mixture was cooled to 23 deg. C to obtain a uniform liquid crystal alignment treatment agent. The composition of the obtained liquid crystal alignment treatment agent is shown in Table 1.

&Lt; Evaluation of voltage holding ratio &

With respect to the liquid crystal alignment treatment agent, the voltage holding ratio of the liquid crystal cell was evaluated as follows.

The liquid crystal alignment treatment agent was spin-coated on a glass substrate having a transparent electrode formed thereon, dried on a hot plate at 70 ° C for 70 seconds, and then baked on a hot plate at 210 ° C for 10 minutes to form a 100 nm thick coating film. The coated film surface was rubbed with a rayon device having a roll diameter of 120 mm at a roll speed of 1000 rpm, a roll advancing speed of 50 mm / sec and a press-in amount of 0.3 mm to obtain a substrate having a liquid crystal alignment film formed thereon.

Two sheets of the substrates were prepared, a spacer of 6 mu m was spread on the surface of the liquid crystal alignment film, the sealant was printed thereon, and the other liquid crystal alignment film surface was faced to direct the rubbing direction And then the sealant was cured to prepare an empty cell. A liquid crystal MLC-2003 (manufactured by Merck Japan Co., Ltd.) was injected into this vacant cell by a reduced pressure injection method and the injection port was sealed to obtain a twisted nematic liquid crystal cell.

A voltage of 4 V was applied to the liquid crystal cell at a temperature of 90 占 폚 for 60 占 퐏 and a voltage of 16.67 ms was measured to determine the degree of voltage retention. For the measurement of the voltage holding ratio, a VHR-1 voltage holding ratio measuring apparatus manufactured by Toyota Technica was used. The evaluation results are shown in Table 2.

<Measurement of tilt angle>

Using the liquid crystal cell obtained in the same manner as in < Production of liquid crystal cell >, the tilt angle of the liquid crystal was measured. For the measurement, TBA107 manufactured by Autronic was used. The measurement was conducted before heating (23 ° C) and while maintaining the liquid crystal cell at 60 ° C. The results are shown in Table 3.

&Lt; Evaluation of liquid crystal alignment property in weak rubbing >

A liquid crystal cell was manufactured under the same conditions except that the substrate was pasted so that the pressing-in of the rubbing roller was changed to 0.2 mm and the rubbing direction was 180 degrees (anti-parallel) in the < Evaluation of voltage holding ratio >. At that time, the presence or absence of the liquid crystal alignment from the injection port of the liquid crystal cell after the liquid crystal injection was observed, and the following evaluation was performed.

?: No flow alignment observed.

?: A little flow orientation is observed.

X: Many stripe-like flow orientations are observed.

The evaluation results are shown in Table 3.

<Evaluation of rubbing resistance>

In the < evaluation of voltage holding ratio >, rubbing was performed under the condition that the rubbing roller was press-fitted at 0.5 mm, thereby manufacturing a substrate having a liquid crystal alignment film formed thereon. The surface of the liquid crystal alignment film was observed with a laser microscope, and the following evaluation was conducted visually.

?: Almost no scraping or rubbing scratches occur.

X: Residual occurs or rubbing scratch occurs.

The evaluation results are shown in Table 3.

&Lt; Evaluation of drying speed &

The liquid crystal alignment treatment agent was spin-coated on a chromium-deposited glass substrate (hereinafter referred to as a Cr substrate) (size 10 cm x 10 cm) so as to have a film thickness of 100 nm. Then, at a temperature of 23 캜 and a humidity of 45%, the time from the completion of the spin coating to the uniform drying of the film was measured. The result was 340 seconds.

<Evaluation of whitening characteristics>

About 0.1 ml of the above liquid crystal alignment treatment agent was dropped on the Cr substrate, and left in an environment of a temperature of 23 캜 and a humidity of 45%. The vicinity of the edge of the droplet and the vicinity of the center were observed with a microscope every hour. The vicinity of the edge of the droplet was observed at a magnification of 100, and the center of the droplet was observed at a magnification of 50 times. And when the agglomerate was observed in the vicinity of the edge and the center of the droplet within 6 h, it was evaluated as &quot; x &quot; The results are shown in Table 2.

&Lt; Evaluation of printing unevenness &

The liquid crystal alignment treatment agent was subjected to flexographic printing (tact time 30 seconds) using an alignment film printing machine (&quot; Ong Stromer &quot; After the first ball operation was performed 10 times, printing was started, and the 10th printed substrate was used for observation. The substrate after printing was left on a hot plate at 80 캜 for 5 minutes to conduct temporary drying of the coating film. The vicinity of the printed edge after drying was observed with an optical microscope (&quot; ECLIPSE ME600 &quot; manufactured by Nikon Corporation) at 50 times, and the film thickness unevenness did not occur and the occurrence was evaluated as x. The results are shown in Table 2.

&Lt; Evaluation of foreign matter at the time of printing &

Printing was performed using the above apparatus. After the ball was run 10 times, the printing machine was stopped for 1 minute and the printing plate was dried. Thereafter, one Cr substrate was printed and fired in the same manner as described above. The fired substrate was observed near the printing edge with a co-focusing laser microscope (&quot; VL2000 &quot;, manufactured by Laser Tech Co., Ltd.), and it was found that no foreign matter of 3 占 퐉 or less was generated near the printing edge ×. The results are shown in Table 2.

<Evaluation of Storage Stability>

The liquid crystal alignment treatment agent was stored at -20 占 폚 for 2 months, and those without cloudiness of precipitation and varnish were rated?, Those with cloudiness of precipitation and varnish were evaluated as?.

(Example 2)

After 21.00 g of the solution obtained in the same manner as in Synthesis Example 2 was cooled to 23 占 폚, 3.87 g of? BL, 10.21 g of NEP and 15.32 g of BC were added and stirred at a temperature of 50 占 폚 for 20 hours. After completion of the stirring, the mixture was cooled to 23 deg. C to obtain a uniform liquid crystal alignment treatment agent. The composition of the obtained liquid crystal alignment treatment agent is summarized in Table 1.

Using this liquid crystal alignment treatment agent, the voltage holding ratio, the tilt angle, the liquid crystal orientation, the rubbing resistance, the drying speed, the whiteness characteristic, the unevenness in printing, the foreign matter at the time of printing, and the storage stability were evaluated in the same manner as in Example 1. The results are shown in Tables 2 and 3.

(Example 3)

18.77 g of the solution obtained in the same manner as in Synthesis Example 2 was cooled to 23 占 폚, then 7.08 g of? BL, 4.80 g of NCP and 14.40 g of BC were added and the mixture was stirred at a temperature of 50 占 폚 for 20 hours. After completion of the stirring, the mixture was cooled to 23 deg. C to obtain a uniform liquid crystal alignment treatment agent. The composition of the obtained liquid crystal alignment treatment agent is summarized in Table 1.

Using this liquid crystal alignment treatment agent, the voltage holding ratio, the tilt angle, the liquid crystal orientation, the rubbing resistance, the drying speed, the whiteness characteristic, the unevenness in printing, the foreign matter at the time of printing, and the storage stability were evaluated in the same manner as in Example 1. The results are shown in Tables 2 and 3.

(Example 4)

After 19.49 g of the solution obtained in the same manner as in Synthesis Example 2 was cooled to 23 占 폚, 3.28 g of? BL, 9.60 g of NCP and 14.40 g of BC were added and the mixture was stirred at a temperature of 50 占 폚 for 20 hours. After completion of the stirring, the mixture was cooled to 23 deg. C to obtain a uniform liquid crystal alignment treatment agent. The composition of the obtained liquid crystal alignment treatment agent is shown in Table 1.

Using this liquid crystal alignment treatment agent, the voltage holding ratio, the tilt angle, the liquid crystal orientation, the rubbing resistance, the drying speed, the whiteness characteristic, the unevenness in printing, the foreign matter at the time of printing, and the storage stability were evaluated in the same manner as in Example 1. The results are shown in Tables 2 and 3.

(Example 5)

The solution obtained in the same manner as in Synthesis Example 3 was cooled to room temperature, 2.66 g of NEP and 8.00 g of BC were added and the mixture was stirred at a temperature of 50 ° C for 20 hours. After completion of the stirring, the mixture was cooled to 23 deg. C to obtain a uniform liquid crystal alignment treatment agent. The composition of the obtained liquid crystal alignment treatment agent is shown in Table 1.

Using this liquid crystal alignment treatment agent, the voltage holding ratio, the tilt angle, the liquid crystal orientation, the rubbing resistance, the drying speed, the whiteness characteristic, the unevenness in printing, the foreign matter at the time of printing, and the storage stability were evaluated in the same manner as in Example 1. The results are shown in Tables 2 and 3.

(Example 6)

After 20 g of the solution obtained in the same manner as in Synthesis Example 7 was cooled to room temperature, 8.8 g of? BL, 4.8 g of NEP and 14.4 g of BC were added and the mixture was stirred at a temperature of 50 占 폚 for 20 hours. After completion of the stirring, the mixture was cooled to 23 deg. C to obtain a uniform liquid crystal alignment treatment agent. The composition of the obtained liquid crystal alignment treatment agent is shown in Table 1.

Using this liquid crystal alignment treatment agent, the voltage holding ratio, the tilt angle, the liquid crystal orientation, the rubbing resistance, the drying speed, the whiteness characteristic, the unevenness in printing, the foreign matter at the time of printing, and the storage stability were evaluated in the same manner as in Example 1. The results are shown in Tables 2 and 3.

(Example 7)

20 g of the solution obtained in the same manner as in Synthesis Example 7 was cooled to room temperature, 4.0 g of? BL, 14.4 g of NEP and 9.6 g of BC were added and the mixture was stirred at a temperature of 50 占 폚 for 20 hours. After completion of the stirring, the mixture was cooled to 23 deg. C to obtain a uniform liquid crystal alignment treatment agent. The composition of the obtained liquid crystal alignment treatment agent is shown in Table 1.

Using this liquid crystal alignment treatment agent, the voltage holding ratio, the tilt angle, the liquid crystal orientation, the rubbing resistance, the drying speed, the whiteness characteristic, the unevenness in printing, the foreign matter at the time of printing, and the storage stability were evaluated in the same manner as in Example 1. The results are shown in Tables 2 and 3.

(Example 8)

20 g of the solution obtained in Synthesis Example 9 and 80 g of the solution obtained in Synthesis Example 11 were stirred at 23 占 폚 for 20 hours. After completion of the stirring, a uniform liquid crystal alignment treatment agent was obtained. The composition of the obtained liquid crystal alignment treatment agent is shown in Table 1.

Using this liquid crystal alignment treatment agent, the voltage holding ratio, the tilt angle, the liquid crystal orientation, the rubbing resistance, the drying speed, the whiteness characteristic, the unevenness in printing, the foreign matter at the time of printing, and the storage stability were evaluated in the same manner as in Example 1. The results are shown in Tables 2 and 3.

(Example 9)

20 g of the solution obtained in Synthesis Example 13 and 80 g of the solution obtained in Synthesis Example 14 were stirred at 23 占 폚 for 20 hours. After completion of the stirring, a uniform liquid crystal alignment treatment agent was obtained. The composition of the obtained liquid crystal alignment treatment agent is shown in Table 1.

Using this liquid crystal alignment treatment agent, the voltage holding ratio, the tilt angle, the liquid crystal orientation, the rubbing resistance, the drying speed, the whiteness characteristic, the unevenness in printing, the foreign matter at the time of printing, and the storage stability were evaluated in the same manner as in Example 1. The results are shown in Tables 2 and 3.

(Example 10)

60 g of the solution obtained in the same manner as in Synthesis Example 16 was cooled to room temperature, 20 g of DMI and 20 g of EC were added and the mixture was stirred at a temperature of 50 캜 for 20 hours. After completion of the stirring, the mixture was cooled to 23 deg. C to obtain a uniform liquid crystal alignment treatment agent. The composition of the obtained liquid crystal alignment treatment agent is shown in Table 1.

Using this liquid crystal alignment treatment agent, the voltage holding ratio, the tilt angle, the liquid crystal orientation, the rubbing resistance, the drying speed, the whiteness characteristic, the unevenness in printing, the foreign matter at the time of printing, and the storage stability were evaluated in the same manner as in Example 1. The results are shown in Tables 2 and 3.

(Example 11)

60 g of the solution obtained in the same manner as in Synthesis Example 16 was cooled to room temperature, 10 g of NMP and 30 g of BC were added and the mixture was stirred at a temperature of 50 캜 for 20 hours. After completion of the stirring, the mixture was cooled to 23 deg. C to obtain a uniform liquid crystal alignment treatment agent. The composition of the obtained liquid crystal alignment treatment agent is shown in Table 1.

Using this liquid crystal alignment treatment agent, the voltage holding ratio, the tilt angle, the liquid crystal orientation, the rubbing resistance, the drying speed, the whiteness characteristic, the unevenness in printing, the foreign matter at the time of printing, and the storage stability were evaluated in the same manner as in Example 1. The results are shown in Tables 2 and 3.

(Example 12)

The solution obtained in the same manner as in Synthesis Example 18 was cooled to room temperature, 2.66 g of NEP and 8.00 g of BC were added and the mixture was stirred at a temperature of 50 캜 for 20 hours. After completion of the stirring, the mixture was cooled to 23 deg. C to obtain a uniform liquid crystal alignment treatment agent. The composition of the obtained liquid crystal alignment treatment agent is shown in Table 1.

Using this liquid crystal alignment treatment agent, the voltage holding ratio, the tilt angle, the liquid crystal orientation, the rubbing resistance, the drying speed, the whiteness characteristic, the unevenness in printing, the foreign matter at the time of printing, and the storage stability were evaluated in the same manner as in Example 1. The results are shown in Tables 2 and 3.

(Comparative Example 1)

The solution obtained in the same manner as in Synthesis Example 4 was cooled to 23 占 폚, 2.66 g of NMP and 8.00 g of BC were added and the mixture was stirred at a temperature of 50 占 폚 for 20 hours. After completion of the stirring, the mixture was cooled to 23 deg. C to obtain a uniform liquid crystal alignment treatment agent. The composition of the obtained liquid crystal alignment treatment agent is summarized in Table 1.

Using this liquid crystal alignment treatment agent, the voltage holding ratio, the tilt angle, the liquid crystal orientation, the rubbing resistance, the drying speed, the whiteness characteristic, the unevenness in printing, the foreign matter at the time of printing, and the storage stability were evaluated in the same manner as in Example 1. The results are shown in Tables 2 and 3. No foreign matter was observed, but whitening and film thickness unevenness were observed.

(Comparative Example 2)

After 19.49 g of the solution obtained in the same manner as in Synthesis Example 2 was cooled to 23 占 폚, 3.28 g of? BL, 9.60 g of NMP and 14.40 g of BC were added and the mixture was stirred at a temperature of 50 占 폚 for 20 hours. After completion of the stirring, the mixture was cooled to 23 deg. C to obtain a uniform liquid crystal alignment treatment agent. The composition of the obtained liquid crystal alignment treatment agent is shown in Table 1.

Using this liquid crystal alignment treatment agent, the voltage holding ratio, the tilt angle, the liquid crystal orientation, the rubbing resistance, the drying speed, the whiteness characteristic, the unevenness in printing, the foreign matter at the time of printing, and the storage stability were evaluated in the same manner as in Example 1. The results are shown in Tables 2 and 3. The whiteness characteristics were good and no foreign matter was observed, but film thickness unevenness was observed.

(Comparative Example 3)

After 19.49 g of the solution obtained in the same manner as in Synthesis Example 2 was cooled to 23 占 폚, 9.03 g of? BL, 9.13 g of BC and 9.13 g of DPM were added and stirred at a temperature of 50 占 폚 for 20 hours. After completion of the stirring, the mixture was cooled to 23 deg. C to obtain a uniform liquid crystal alignment treatment agent. The composition of the obtained liquid crystal alignment treatment agent is shown in Table 1.

Using this liquid crystal alignment treatment agent, the voltage holding ratio, the tilt angle, the liquid crystal orientation, the rubbing resistance, the drying speed, the whiteness characteristic, the unevenness in printing, the foreign matter at the time of printing, and the storage stability were evaluated in the same manner as in Example 1. The results are shown in Tables 2 and 3. Though the whitening characteristics were good, the film thickness irregularity occurred and foreign substances were also observed.

(Example 13)

The solution obtained in the same manner as in Synthesis Example 5 was cooled to room temperature, 6.40 g of NCP and 9.60 g of BC were added, and the mixture was stirred at a temperature of 50 ° C for 20 hours. After completion of the stirring, the mixture was cooled to 23 deg. C to obtain a uniform liquid crystal alignment treatment agent. The composition of the obtained liquid crystal alignment treatment agent is shown in Table 1.

Using this liquid crystal alignment treatment agent, the voltage holding ratio, the tilt angle, the liquid crystal orientation, the rubbing resistance, the drying speed, the whiteness characteristic, the unevenness in printing, the foreign matter at the time of printing, and the storage stability were evaluated in the same manner as in Example 1. The results are shown in Tables 2 and 3.

[Table 1-1]

[Table 1-2]

[Table 2]

[Table 3]

Industrial availability

The liquid crystal alignment treatment agent of the present invention can produce a narrow gap liquid crystal panel at a good yield because there is no generation of coagulated matter which is good in the voltage holding property and causes unevenness in the gap of the liquid crystal panel at the time of printing. Therefore, the liquid crystal display device manufactured by using the liquid crystal alignment treatment agent of the present invention can be a highly reliable liquid crystal display device and can be used for a TN liquid crystal display device, an STN liquid crystal display device, a TFT liquid crystal display device, an OCB liquid crystal display device, A transverse electric field type liquid crystal display element, a VA liquid crystal display element, and the like.

Also, the entire contents of the specification, claims, and abstract of Japanese Patent Application No. 2008-146792 filed on June 4, 2008 are incorporated herein by reference as the disclosure of the specification of the present invention.

Claims (11)

A resin component containing a polyimide obtained by imidizing a polyamic acid obtained by reacting a diamine component with a tetracarboxylic dianhydride and a resin component containing a polyimide obtained by reacting a resin component containing N-ethyl-2-pyrrolidone or N-cyclohexyl- Wherein the diamine component is a diaminobenzene having a disubstituted amino group substituted with an alkenyl group having 2 or 3 carbon atoms. 2. The liquid crystal alignment treatment agent according to claim 1, The method according to claim 1,
Wherein the pyrrolidone compound is N-ethyl-2-pyrrolidone and the N-ethyl-2-pyrrolidone is 5 to 80 mass% of the solvent component. The method according to claim 1,
Wherein the pyrrolidone compound is N-cyclohexyl-2-pyrrolidone and the N-cyclohexyl-2-pyrrolidone is 5 to 40 mass% of the solvent component. The method according to claim 1,
1. A liquid crystal alignment treatment agent comprising a resin component in an amount of 1 to 10 mass% and a solvent component in an amount of 90 to 99 mass%. The method according to claim 1,
Wherein the diaminobenzene having a disubstituted amino group substituted with an alkenyl group having 2 or 3 carbon atoms is a diamine represented by the following formula [1].
[Chemical Formula 1]

6. The method of claim 5,
Wherein the diamine component further contains a diamine represented by the following formula [32].
(2)

(Wherein k represents an integer of 1 to 20) 6. The method of claim 5,
Wherein the diamine represented by the formula [1] contains 20 to 90 mol% of all the diamine components. 8. The method of claim 7,
Wherein the diamine component further contains a diamine represented by the following formula [32] and the diamine represented by the formula [32] is contained in an amount of 5 to 40 mol% of the total diamine component.

(Wherein k represents an integer of 1 to 20) A liquid crystal alignment film obtained by applying the liquid crystal alignment treatment agent according to any one of claims 1 to 8 onto a substrate on which an electrode is formed and baking. A liquid crystal display element having the liquid crystal alignment film according to claim 9. delete