KR101742838B1 - Liquid crystal aligning agent and liquid crystal display element using same - Google Patents

Abstract

(식 중, Ar 은 동소 고리 방향족 화합물, 질소 원자 함유 복소 고리 방향족 화합물을 나타내고, 고리를 구성하는 탄소 원자 상 또는 질소 원자 상의 수소 원자는 치환되어 있어도 된다)Provided is a liquid crystal alignment treatment agent which is resistant to film peeling and scoring at the time of rubbing, has a high voltage holding ratio, and can hardly cause accumulation of initial charge even when a direct current voltage is applied.
A liquid crystal composition comprising at least one polymer selected from the group consisting of a polyamic acid obtained by reacting a diamine component containing a diamine represented by the following formula [1] with a tetracarboxylic acid dianhydride component, and a polyimide obtained by imidizing the polyamic acid: Orientation treatment agent.
[Chemical Formula 1]

(Wherein Ar represents an aromatic heterocyclic aromatic compound or a nitrogen atom-containing heterocyclic aromatic compound, the hydrogen atom on the carbon atom or the nitrogen atom constituting the ring may be substituted)

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, a liquid crystal alignment film, and a liquid crystal display element used for a liquid crystal display element.

At present, as a liquid crystal alignment film of a liquid crystal display element, a so-called polyimide-based liquid crystal alignment film in which a liquid crystal alignment treatment agent containing a solution of a polyimide precursor or a soluble polyimide such as polyamic acid as a main component is applied and baked, Is mainly used.

The liquid crystal alignment film not only controls the alignment state of the liquid crystal but also affects the characteristics of the liquid crystal display element. Particularly, characteristics such as suppression of a decrease in contrast of a liquid crystal display element and reduction of a residual image phenomenon have become more important as the film peeling and scraping problems during rubbing treatment and the high definition of a liquid crystal display element become significant.

A liquid crystal alignment treatment agent containing a tertiary amine having a specific structure is used in addition to a polyamic acid or an imide group-containing polyamic acid as a short time until the afterimage generated by the DC voltage disappears in the polyimide- (See, for example, Patent Document 1), and a liquid crystal alignment treatment agent containing a soluble polyimide using a specific diamine having a pyridine skeleton or the like as a raw material (see, for example, Patent Document 2).

In addition, in a polyimide-based liquid crystal alignment film, the voltage holding ratio is high, and the time until the after-image generated by the DC voltage disappears is short. In addition to the polyamic acid and its imidized polymer, A liquid crystal alignment treatment agent containing an extremely small amount of a compound containing an acid group, a compound containing one carboxylic acid anhydride group in the molecule, and a compound containing one tertiary amino group in the molecule (for example, See Patent Document 3).

Japanese Patent Application Laid-Open No. 9-316200 Japanese Patent Application Laid-Open No. 10-104633 Japanese Patent Application Laid-Open No. 8-76128

SUMMARY OF THE INVENTION In view of the above situation, it is an object of the present invention to provide a liquid crystal alignment film which is resistant to film peeling and scoring at the time of rubbing, has a high voltage holding ratio, and is capable of obtaining a liquid crystal alignment film in which initial charge accumulation is hardly generated even when a DC voltage is applied to the liquid crystal cell An object of the present invention is to provide an orientation treatment agent.

As a result of intensive studies, the present inventors have found that a liquid crystal alignment treatment agent containing a polyamic acid using a specific diamine compound containing a novel compound and / or a polyimide obtained by imidizing the polyamic acid as a diamine component And found to be very effective for achieving the present invention, thereby completing the present invention. That is, the present invention has the following points.

(1) a polyamic acid obtained by reacting a diamine component containing a diamine compound represented by the following formula [1] with a tetracarboxylic acid dianhydride component, and a polyimide obtained by imidizing the polyamic acid A liquid crystal alignment treatment agent characterized by containing at least one kind of polymer.

[Chemical Formula 1]

(Wherein Ar represents an aromatic ring aromatic compound or a nitrogen atom-containing heterocyclic aromatic compound, and the hydrogen atom on the carbon atom or the nitrogen atom constituting the ring may be substituted)

(2) The liquid crystal alignment treatment agent according to the above (1), wherein Ar in formula [1] is a heterocyclic aromatic compound having 6 atomic rings or a nitrogen atom-containing heterocyclic aromatic compound having 6 atomic rings.

(3) The liquid crystal alignment treating agent according to the above (1), wherein Ar in the formula (1) is a heterocyclic aromatic compound containing a nitrogen atom in a five-membered ring.

(4) The liquid crystal alignment treatment agent according to the above (1), wherein Ar in formula [1] is benzene, pyridine, pyridazine, pyrimidine, pyrazine or triazine.

(5) The liquid crystal alignment treatment agent according to the above (1), wherein Ar in formula [1] is oxazole, oxadiazole, thiazole, thiadiazole, pyrrole, imidazole, pyrazole or triazole.

(6) The liquid crystal alignment treating agent according to the above (1), wherein the diamine compound represented by the formula [1] is any of the compounds represented by the following general formulas [4] to [6] (Ar has the same meaning as described above).

(2)

(7) The liquid crystal alignment treating agent according to (1), wherein the diamine compound represented by the formula [1] is a compound represented by the following formula [2].

(3)

(8) The liquid crystal alignment treatment agent according to any one of (1) to (7), wherein the diamine component contains at least 10 mol% of a diamine compound represented by the following formula [3].

H ₂ N-Ar'-R ₁ -NH-R ₂ [3]

(Wherein Ar 'represents a phenylene group or a naphthylene group, R ₁ Represents an alkylene group of 1 to 5 carbon atoms, and R < ₂ > Represents an alkyl group having 1 to 5 carbon atoms)

(9) The liquid crystal alignment treatment agent according to any one of (1) to (8), wherein the tetracarboxylic acid dianhydride component comprises a tetracarboxylic acid dianhydride having an alicyclic structure or an aliphatic structure.

(10) A liquid crystal alignment film obtained by applying the liquid crystal alignment treatment agent described in any one of (1) to (9) above onto a substrate having electrodes attached thereto and firing it.

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

(12) A diamine compound represented by the following formula [1].

[Chemical Formula 4]

(Wherein Ar represents an aromatic ring aromatic compound or a nitrogen atom-containing heterocyclic aromatic compound, and a hydrogen atom on a carbon atom or a nitrogen atom constituting the ring may be substituted with an organic group)

(13) The diamine compound according to (12), wherein Ar in the formula (1) is a heterocyclic aromatic compound having 6 atomic rings or a nitrogen atom-containing heterocyclic aromatic compound having 6 atomic rings.

(14) The diamine compound according to the above (12), wherein Ar in the formula (1) is a nitrogen atom-containing heterocyclic aromatic compound having 5 atomic rings.

(15) The diamine compound according to the above (12), wherein Ar in formula [1] is benzene, pyridine, pyridazine, pyrimidine, pyrazine or triazine.

(16) The diamine compound according to (12), wherein Ar in formula [1] is oxazole, oxadiazole, thiazole, thiadiazole, pyrrole, imidazole, pyrazole or triazole.

(17) The diamine compound according to (12), wherein the diamine compound represented by the formula [1] is any of the compounds represented by the following general formulas [4] to [6].

[Chemical Formula 5]

(18) The diamine compound according to the above (12), wherein the diamine compound represented by the formula [1] is a compound represented by the following formula [2].

[Chemical Formula 6]

(19) A polyamic acid obtained by reacting a diamine component containing the diamine compound described in any one of (12) to (18) above with a tetracarboxylic acid dianhydride component, or a polyimide obtained by imidizing the polyamic acid.

The liquid crystal alignment treatment agent of the present invention is resistant to film peeling and scoring at the time of rubbing, has a high voltage holding ratio and can obtain a liquid crystal alignment film in which initial charge accumulation is hardly generated even when a DC voltage is applied to the liquid crystal cell, It is possible to manufacture a liquid crystal panel having excellent characteristics.

Further, according to the present invention, novel diamine compounds useful as raw materials for polyamic acid and polyimide as liquid crystal alignment treatment agents are provided.

The liquid crystal alignment treatment agent of the present invention is a polyamic acid obtained by reacting a diamine component containing a specific diamine compound represented by the following formula [1] with a tetracarboxylic acid dianhydride component, and a polyamic acid obtained by reacting at least a polyamic acid Is a liquid crystal alignment treatment agent containing one kind of polymer. This particular diamine compound contains a novel compound of the prior art. By using this specific diamine compound, it is possible to reduce film peeling and shaving at the time of rubbing even in the rubbing treatment required for the liquid crystal alignment treatment, The retention rate is high and accumulation of the initial charge can be made less likely to occur even when a DC voltage is applied to the liquid crystal cell.

The diamine compound of the formula [1]

In the above formula [1], Ar is an aromatic heterocyclic compound or a nitrogen atom-containing heterocyclic aromatic compound. Since Ar is a site participating in the transfer of charges, it is preferable that the structure is electrically active Among them, a nitrogen-containing heterocyclic aromatic compound is preferred.

Ar is not particularly limited as long as it is an aromatic ring compound having an aromatic ring or a nitrogen atom and a heterocyclic aromatic compound having a nitrogen atom. However, when a bulky structure or a ring having a large molecular weight is introduced, there is a possibility of disturbing the liquid crystal alignability.

Since Ar constitutes a monovalent group, Ar is described as an aromatic ring compound or a nitrogen atom-containing heterocyclic aromatic compound for the sake of convenience as described above. Since Ar is a monovalent group, strictly speaking, In the case of a cyclic aromatic compound, it is a residue obtained by removing one hydrogen atom of an aromatic ring aromatic compound. In the case of a heterocyclic aromatic compound containing a nitrogen atom, a residue obtained by removing one hydrogen atom from a nitrogen atom- it means. The same applies when Ar is benzene, pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazole, oxadiazole, thiazole, thiadiazole, pyrrole, imidazole, pyrazole, or triazole. Quot; means each residue in which one hydrogen atom is removed.

Ar in the formula [1] is not particularly limited in the form of the ring of the heterocyclic aromatic compound or the nitrogen atom-containing heterocyclic aromatic compound, and good characteristics can be obtained even if it is a five-membered ring or a six-membered ring.

It is known that the heterocyclic aromatic compound of the 5-membered ring or the heterocyclic aromatic compound containing the nitrogen atom has higher reactivity of the ring itself than those of the 6-membered ring. Therefore, it is preferable from the viewpoint of rubbing resistance that the rings react with each other during the baking process at a high temperature, which is carried out at the time of forming the liquid crystal alignment film, to cause crosslinking. On the other hand, from the viewpoint of the electrical characteristics of the liquid crystal alignment film, an aromatic ring compound having six atoms or a nitrogen atom-containing heterocyclic aromatic compound rich in structural stability is preferable.

In the formula [1], Ar may be connected to the same ring such as biphenylene or bipyridine, or may be connected to each other such as phenylpyridine or phenylthiophene. It may also take a coordinated structure such as quinoline or benzimidazole.

Specific examples of the aromatic ring aromatic compound include cyclopentadiene, benzene, azulene, naphthalene, anthracene, phenanthrene, pyrene, naphthacene, benzopyrrene, perylene, pentacene, phenalene, indene, fluorene, Phenylene, and the like.

Specific examples of the nitrogen atom-containing heterocyclic aromatic compound include pyrrole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, tetrazine, imidazole, pyrazole, oxazole, isoxazole, Wherein the solubilizing agent is selected from the group consisting of a sol, a thiazole, an isothiazole, a thiadiazole triazole, a tetrazole, an indole, an indazole, a benzoimidazole, a benzooxazole, a benzoisooxazole, a benzothiazole, a benzoisothiazole, a quinoline, Pyrimidines, pyrazines, pyrimidines, pyrazines, pyrazines, pyrazines, pyrazines, pyrazines, pyrazines, pyrazines, pyrazines, pyrazines, pyrazines, pyrazines, , Carbolin, and the like. The N-H moiety in pyrrole, pyrazole, imidazole, etc. may be as it is or may be alkylated such as by methylation.

Specific preferred examples of Ar include cyclopentadiene, benzene, azulene, naphthalene, indene, fluorene, biphenylene, pyrrole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, tetrazine, imidazole, The compounds of formula (I) are selected from the group consisting of pyrazole, oxazole, isoxazole, oxadiazole, thiazole, isothiazole, thiadiazole, triazole, tetrazole, indole, indazole, benzoimidazole, benzoxazole, Wherein the compound is selected from the group consisting of a benzene ring, a benzene ring, a benzene ring, a benzene ring, a benzene ring, a benzene ring, a benzene ring, a benzoquinoline ring, a benzoquinoline ring, Lysine, quinolizine, and carbolin. Particularly preferred are benzene, pyridine, pyridazine, pyrimidine, pyrazine, triazinepyrrol, oxazole, oxadiazole, thiazole, thiadiazole, imidazole, pyrazole or triazole.

The hydrogen atom on the carbon atom or the nitrogen atom constituting the ring in the above-mentioned heterocyclic aromatic compound or nitrogen atom-containing heterocyclic aromatic compound may be substituted. The kind and number of the substituent group are not particularly limited, and examples thereof include electron-donating substituents having relatively small molecular weights such as methyl group, ethyl group, alkoxyl group, methoxy group, ethoxy group, amino group and dimethylamino group, and carboxyl groups, nitro groups and cyano groups An electron-withdrawing substituent having a relatively small molecular weight is preferable because it activates the acceptance of electrons. The position of the substituent group with respect to the aromatic ring aromatic compound or the heterocyclic aromatic compound is not particularly limited, but in the case of the nitrogen-containing heterocyclic aromatic compound, the substituent is preferably a position not adjacent to the nitrogen atom.

On the other hand, from the viewpoints of liquid crystal alignability, rubbing resistance and ease of synthesis when used as a liquid crystal alignment film, it is preferable to use an unsubstituted or substituted heterocyclic aromatic compound or nitrogen atom-containing heterocyclic aromatic compound substituted with a relatively small substituent such as methyl group or ethyl group desirable.

 In the diamine represented by the general formula [1], the position of each substituent on the benzene ring is not particularly limited. From the viewpoint of the liquid crystal alignability in the case of using a liquid crystal alignment film, the positional relationship between the two amino groups is preferably meta or para, and more preferably from the viewpoint of enhancing solvent solubility of the polyamic acid or polyimide. When the positional relationship between the two amino groups is meta, that is, in the case of the 1,3-diaminobenzene structure, the position of the methylene ester is preferably at the position of 4 or 5. Particularly, , The position of 5 is particularly preferable.

 Specific preferred examples of the diamine represented by the general formula [1] include compounds represented by the following general formulas [2], [4], [5] or [6].

(7)

In addition, Ar is preferably benzene, pyridine, pyridazine, pyrimidine, pyrazine, triazinepyrrol, oxazole, oxadiazole, thiazole, thiadiazole, imidazole, pyrazole or triazole.

≪ Synthesis of diamine compound of formula [1] >

The method for synthesizing the diamine represented by the general formula [1] is not particularly limited. For example, a method of synthesizing a dinitro compound represented by the following general formula [7] and then converting the nitro group to an amino group by a conventional method . ≪ / RTI >

[Chemical Formula 8]

The dinitro compound represented by the above general formula [7] can be synthesized by esterification of the corresponding dinitrobenzyl alcohol as shown below. That is, it is synthesized by reacting dinitrobenzyl alcohol with carboxylic acid chloride or acid dianhydride in the presence of a base such as pyridine or triethylamine. In addition, Ar corresponds to Ar in the aimed diamine of the above general formula [1].

Examples of the dinitrobenzyl alcohol include 2,4-dinitrobenzyl alcohol, 3,5-dinitrobenzyl alcohol, 2,5-dinitrobenzyl alcohol and the like.

[Chemical Formula 9]

The method for reducing the dinitro compound represented by the above general formula [7] to obtain the diamine represented by the general formula [1] is not particularly limited and includes palladium-carbon, platinum oxide, Raney nickel, platinum black, rhodium- Hydrazine, hydrogen chloride or the like in a solvent such as ethyl acetate, toluene, tetrahydrofuran, dioxane or alcohol using platinum carbon or the like as a catalyst.

≪ Diamine component >

By reacting the diamine represented by the above formula [1] with a tetracarboxylic acid dianhydride, a polyamic acid can be obtained. In the present invention, the diamine component used in the synthesis of the polyamic acid may be only the diamine represented by the formula [1], and one or more selected from other diamines may be combined.

By containing the diamine represented by the formula [1] as the diamine component, the solubility of the obtained polyamic acid and the polyimide imidized with the polyamic acid in an organic solvent can be increased. Further, the liquid crystal alignment film obtained from the liquid crystal alignment treatment agent containing the polyamic acid or polyimide is excellent in rubbing resistance, has a high voltage holding ratio, and is less prone to accumulation of initial charge even when a DC voltage is applied to the liquid crystal cell Loses. In order to obtain such properties, the diamine represented by the formula [1] is preferably 5 to 100 mol%, more preferably 10 to 80 mol%, and particularly preferably 10 to 100 mol% of the total diamine component used in the synthesis of the polyamic acid Is 20 to 50 mol%.

In the diamine component, the diamine used in combination with the diamine represented by the formula [1] is not particularly limited. Specific examples of such diamines 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 diamine include aromatic diamines such as o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 2,4-diaminotoluene, 2,5-diaminotoluene, Diamino-N, N-diallylaniline, 2,4-diamino-N, N-diallylaniline, 1,4-diamino-2-methoxybenzene, 2,5- 1,3-diamino-4-chlorobenzene, 3,5-diaminobenzoic acid, 1,4-diamino-2,5-dichlorobenzene, 4,4'-diamino- Phenylethane, 4,4'-diamino-2,2'-dimethylbibenzyl, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 3,4'- Phenylmethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 2,2'-diaminostilbene, 4,4'-diaminostilbene, 4,4'-diaminodiphenyl Ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, '- diaminobenzophenone, 1,3-bis (3-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzoic acid, 4,4'-bis (4-aminophenoxy) bibenzyl, 2, Bis [4- (4-aminophenoxy) methyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, (4-aminophenoxy) phenyl] sulfone, 1,1-bis (4-aminophenyl) cyclohexane, bis (4-aminophenyl) hexafluoro-2,2-bis (4-aminophenyl) Propane, 2,2-bis (4-aminophenyl) hexafluoropropane, 4,4'-diaminodiphenylamine, 2,4-diaminodiphenylamine, 1,8-diaminonaphthalene, 1,5 Diaminopyrrole, 1,8-diaminopyrrene, 2,7-diaminofluorene, 1,3-diaminopyrrole, 1,3-diaminopyrrole, Bis (4-aminophenyl) tetramethyldisiloxane, benzo Bis (4-aminophenyl) butane, 1, 2-bis (4-aminophenyl) Bis (4-aminophenyl) pentane, 1,6-bis (4-aminophenyl) Bis (4-aminophenyl) decane, 1,1-bis (4-aminophenoxy) Bis (4-aminophenoxy) pentane, 1,8-bis (4-aminophenoxy) pentane, Bis (4-aminophenoxy) decane, di (4-aminophenoxy) propane-1,3 Dioate, di (4-aminophenyl) butane-1,4-dioate, di (4-aminophenyl) pentane- Di (4-aminophenyl) octane-1,8-dioate, di (4-aminophenyl) heptane- 1, 10-dioate, 1,3-bis [4- (4-aminophenoxy) phenoxy] propane, Bis [4- (4-aminophenoxy) phenoxy] pentane, 1,6-bis [4- (4-aminophenoxy) phenoxy] heptane, 1,7-bis [4- Bis [4- (4-aminophenoxy) phenoxy] decane, and 1,10-bis [4- (4-aminophenoxy) phenoxy] decane.

Examples of the heterocyclic diamine include 2,6-diaminopyridine, 2,4-diaminopyridine, 2,4-diamino-1,3,5-triazine, 2,7-diaminodibenzofuran, Diaminocarbazole, 2,4-diamino-6-isopropyl-1,3,5-triazine, 2,5-bis (4-aminophenyl) -1,3,4-oxadiazole Sol 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.

Examples of the aromatic-aliphatic diamine include diamines represented by the formula [3].

H ₂ N-Ar'-R ₁ -NH-R ₂ [3]

Wherein R ₁ is an alkylene group having 1 to 5 carbon atoms, preferably 1 to 3 carbon atoms, R ₂ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, preferably hydrogen An atom or a methyl group.

Specific examples of the diamine represented by the formula [3] include 3-aminobenzylamine, 4-aminobenzylamine, 3-amino-N-methylbenzylamine, Amino-N-methylphenethylamine, 3- (3-aminopropyl) aniline, 4- (3-aminopropyl) aniline Aniline, 4- (4-aminobutyl) aniline, 3- (4-methylaminopropyl) aniline, 3- (5-aminopentyl) aniline, 3- (5-methylaminopentyl) aniline, 4- (5-aminophenyl) aniline, 4- (6-aminonaphthyl) methylamine, 2- (6-aminonaphthyl) ethylamine, 3- (6-aminonaphthyl) Yl) ethylamine, and the like.

When the diamine represented by the formula [3] is used in combination with the diamine represented by the formula [1], the solubility of the resulting polyamic acid or polyimide (hereinafter, referred to as a polymer) in an organic solvent is further improved and used as a liquid crystal alignment film The liquid crystal alignability is excellent. Further, when a diamine (hereinafter also referred to as a tilt diamine) for increasing the pretilt angle of a liquid crystal to be described later is used in combination, an effect of further increasing the pretilt angle of the liquid crystal is exhibited. Therefore, when a pretilt angle of the same size is desired, a large tilt angle can be obtained even if the amount of tilted diamine to be used is small. In addition, printing property improvement of the liquid crystal alignment treatment agent can be expected.

The preferred content of the diamine represented by the formula [3] is 10 to 80 mol%, preferably 20 to 70 mol%, of the total diamine component.

Examples of the diamine (also referred to as tilted diamine) capable of increasing the pretilt angle of the liquid crystal include diamines having a long chain alkyl group, a perfluoroalkyl group, an aromatic cyclic group, an aliphatic cyclic group, or a combination thereof, . These diamines can be used in combination with diamines represented by the formula [1].

Specific examples of tilted diamines are shown below, but the present invention is not limited thereto. In the following formulas [12] to [38], j represents an integer of 5 to 20, and k represents an integer of 1 to 20.

[Chemical formula 10]

(11)

[Chemical Formula 12]

[Chemical Formula 13]

[Chemical Formula 14]

[Chemical Formula 15]

[Chemical Formula 16]

Among the diamines of the formulas [12] to [38], the diamine of the formula [12] is preferable because of excellent liquid crystal alignability. The diamines of the formulas [19] to [26] are excellent in the OCB (Optically Compensated Bend) liquid crystal alignment film (OCB orientation film), the vertical alignment mode liquid crystal orientation film (VA orientation film) .

For example, in the TN liquid crystal alignment film (at a pretilt angle of 3 to 5), the content of the diamine of the formula [12] is preferably 10 to 30 mol% of the total diamine component and the OCB orientation film or the VA orientation film (The pretilt angle is 10 to 90 占), the content of the diamine of the formula [19] to [26] is preferably 5 to 40 mol% of the total amount of the diamine component.

Considering the balance of the respective characteristics such as the solubility of the polyamic acid or polyimide used in the liquid crystal alignment treatment agent of the present invention, the orientation of the liquid crystal, the tilt angle, the voltage holding ratio and the accumulated charge, The diamine component represented by the formula [12] is preferably used in an amount of 10 to 50% (formula [1]) / 20 to 80% (formula [3]) / 10 To 30% (formula [12]), more preferably 20 to 40% (formula [1]) / 30 to 50% .

≪ Tetracarboxylic acid dianhydride component >

In the polyamic acid or polyimide required for the liquid crystal alignment treatment agent of the present invention, the tetracarboxylic acid dianhydride component to be reacted with the above-mentioned diamine component is not particularly limited. That is, it may be one type of tetracarboxylic acid dianhydride, or two or more kinds of tetracarboxylic acid dianhydrides may be used in combination.

In the liquid crystal alignment treatment agent of the present invention, the tetracarboxylic acid dianhydride having an alicyclic structure or an aliphatic structure as the tetracarboxylic acid dianhydride to be reacted with the above-mentioned diamine component, for example, It is preferable to use an anhydride.

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 tetra Carboxylic acid dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic acid dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutane 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, (2,5-dioxotetrahydrofuran-3-yl) -1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid anhydride], 1,2,3,4-butane Tetracarboxylic acid dianhydride, bicyclo [3,3,0] octane-2,4,6,8-tetracarboxylic acid dianhydride, 3,3 ', 4,4'-dicyclohexylate Carboxylic acid dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, cis-3,7-dibutylcycloocta-1,5-diene-1,2,5,6-tetracarboxylic acid 2 Anhydride, tricyclo [4.2.1.02,5] nonane-3,4,7,8-tetracarboxylic acid-3,4: 7,8-2 anhydride, hexacyclo [6.6.0.12,7.03,6.19,14.010, 13] hexadecane-4,5,11,12-tetracarboxylic acid-4,5: 11,12-2 anhydride. Among these, use of 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride is preferable because an alignment film excellent in liquid crystal alignability can be obtained.

Furthermore, when the aromatic tetracarboxylic acid dianhydride is used in combination, the liquid crystal alignment property can be improved and the accumulation charge of the liquid crystal cell can escape quickly. 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. Among them, pyromellitic dianhydride is particularly preferable.

Considering the balance of the respective properties such as the solubility of the obtained polyamic acid or polyimide, the orientation of liquid crystal, the voltage holding ratio, and the accumulated charge, it is preferable to use tetracarboxylic acid dianhydride having an alicyclic or aliphatic structure and aromatic tetracarboxylic acid 2 The ratio of the anhydride to be used is preferably 90/10 to 50/50, more preferably 80/20 to 60/40 in terms of the former / the latter molar ratio.

<Polymerization Reaction>

In the present invention, the polymerization reaction method of the tetracarboxylic acid dianhydride component and the diamine component is not particularly limited. Generally, a polymerization reaction can be carried out by mixing in an organic solvent to form a polyamic acid, and the polyamic acid can be converted into a polyimide by dehydration ring closure.

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 polymerization reaction may be carried out in a state in which these plural kinds of components are mixed in advance, or the polymerization reaction may be carried out individually and sequentially.

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 total concentration of the tetracarboxylic acid dianhydride component and the diamine component is too low, it becomes difficult to obtain a polymer having a high molecular weight. When the concentration is too high, the viscosity of the reaction solution becomes The total concentration is preferably 1 to 50% by mass, and more preferably 5 to 30% by mass. The polymerization 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 polymerization reaction is not particularly limited as long as it dissolves the produced polyamic acid. Specific examples thereof include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N- Side, tetramethylurea, pyridine, dimethylsulfone, hexamethylsulfoxide,? -Butyrolactone, and 1,3-dimethylimidazolidinone. These may be used singly or in combination. Further, a solvent which does not dissolve the polyamic acid may be used in combination with the solvent insofar as the produced polyamic acid is not precipitated. In addition, water in the organic solvent inhibits the polymerization reaction, and further causes hydrolysis of the resulting polyamic acid. Therefore, 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 &gt; 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 polyamic acid or polyimide of the present invention is not particularly limited. When it is contained in the liquid crystal alignment treatment agent, the weight average molecular weight is preferably 2,000 to 200,000 from the viewpoint of the strength of the obtained coating film and ease of handling as a liquid crystal alignment treatment agent And more preferably from 5,000 to 50,000.

<Synthesis of polyimide>

The polyimide used in the liquid crystal alignment treatment agent of the present invention is a polyimide obtained by imidizing the above-mentioned polyamic acid. Imidization of the polyamic acid 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 because it has a suitable basicity for promoting the reaction.

Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, and pyromellitic anhydride. Among them, acetic anhydride is preferable because purification of polyimide obtained after completion of imidization becomes easy.

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 adjusting the amount of catalyst, reaction temperature, reaction time, and the like. 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 acyl group. The amount of the acid anhydride is preferably 1 to 30 times, more preferably 1 to 10 times, the molar amount of the acidic group. The reaction temperature is preferably -20 to 250 占 폚, more preferably 0 to 180 占 폚.

Although the imidization rate of the polyimide used in the liquid crystal alignment treatment agent of the present invention is not particularly limited, it is preferable that the imidization ratio is 40% or more, and 60% or more is preferable because the liquid crystal alignment film having a higher voltage holding ratio is obtained , And particularly preferably 80% or more.

In the solution of the polyimide thus obtained, the added catalyst remains, and therefore, when used in a liquid crystal alignment treatment agent, it is preferable to recover and wash the polyimide before use.

The recovery of the polyimide can be carried out by introducing the solution after imidization with stirring of a poor solvent, precipitating the polyimide, and then filtering. Examples of the poor solvent include methanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene and benzene. The recovered polyimide may be washed with this poor solvent. The polyimide thus recovered and washed can be made into a powder at ordinary temperature or under reduced pressure or by heating and drying.

Such an operation can also be carried out for the above-mentioned polyamic acid. For example, in the case where it is not desired to contain the solvent used for the polymerization of polyamic acid in the liquid crystal alignment treatment agent, or when it is desired to remove unreacted monomer components or impurities in the reaction solution, the above precipitation recovery and purification may be carried out .

&Lt; Liquid crystal alignment treatment agent &

The liquid crystal alignment treatment agent of the present invention is a coating liquid containing at least one polymer selected from the above-mentioned polyamic acid and polyimide.

For example, the reaction solution of the above-mentioned polyamic acid or polyimide may be used as it is, or it may be diluted, and the product obtained by precipitation and recovery from the reaction solution may be redissolved in an organic solvent. In the dilution or redissolution 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. Further, it may be mixed with a polyimide solution having a structure different from that described above, or a solution of polyamic acid, or another resin component may be added.

The organic solvent used in the dilution or redissolution step is not particularly limited as long as it dissolves the polymer contained therein. Specific examples thereof include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, Pyrrolidone, N-vinylpyrrolidone, dimethylsulfoxide, tetramethylurea, dimethylsulfone, hexamethylsulfoxide,? -Butyrolactone, and 1,3-dimethyl-imidazolidinone. Among them, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 1,3-dimethylimidazolidinone and? -Butyrolactone are preferably used. These may be used alone or in combination of two or more.

Examples of the solvent to be added for controlling the coating property of the liquid crystal alignment treatment agent to the substrate include ethyl cellosolve, butyl cellosolve, ethyl carbitol, butyl carbitol, ethyl carbitol acetate, ethylene glycol, 1-methoxy- Propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanol, diethylene glycol diethyl ether, propylene glycol monoacetate, propylene glycol diacetate, dipropylene Propylene glycol monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2- (2-ethoxypropoxy) propanol, lactic acid methyl ester , Ethyl lactate, n-propyl lactate, n-butyl lactate, isoamyl lactate and the like. These solvents also include solvents which can not dissolve polyamic acid or polyimide alone, but may be mixed with the liquid crystal alignment treatment agent of the present invention as long as the polymer does not precipitate. Particularly, by appropriately mixing a solvent having a low surface tension, it is possible to improve the uniformity of a coating film upon application to a substrate, and thus the liquid crystal alignment treatment agent of the present invention is preferably used. Of these, butyl cellosolve, ethyl carbitol, dipropylene glycol monomethyl ether and diethylene glycol diethyl ether are particularly preferable from the viewpoint of solubility of polyimide.

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 improved. However, when the addition amount is excessive, polyamic acid, polyimide and the like tend to aggregate. Therefore, the content of the silane coupling agent is preferably 0.5 to 10% by mass, more preferably 1 to 5% by mass based on the total mass of the polyamic acid and the polyimide.

The solid concentration of the liquid crystal alignment treatment agent of the present invention can be suitably changed according to the setting of the thickness of the liquid crystal alignment film to be formed, and it is preferably 1 to 10% by mass. If it is less than 1% by mass, it becomes difficult to form a uniform and defect-free coating film, and if it is more than 10% by mass, the storage stability of the solution may be deteriorated. The solid content referred to here means that the solvent is removed from the liquid crystal alignment treatment agent. The concentration of the polyamic acid or polyimide used in the liquid crystal alignment treatment agent of the present invention is not particularly limited, but is preferably 1% by mass or more, more preferably 3% by mass or more from the viewpoint of the properties of the obtained liquid crystal alignment film By mass, and particularly 5% by mass or more.

The liquid crystal alignment treatment agent thus obtained is preferably filtered before it is applied to the substrate.

<Liquid crystal display element>

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 by rubbing the coated film surface, it is used as a liquid crystal alignment film for rubbing. It is also used as a VA (vertical alignment) liquid crystal alignment film and a photo alignment film which do 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 plastic substrate such as a glass substrate, an acrylic substrate or a polycarbonate substrate can be used, and a substrate on which an ITO electrode for liquid crystal driving is formed is used Which is preferable from the viewpoint of simplification of the process. In the reflection type liquid crystal display element, if it is only a substrate on one side, it may be opaque such as a silicon wafer. In this case, a material that reflects light such as aluminum can also be used as the electrode in this case.

As a method of 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 terms of productivity, the flexographic printing method is widely used industrially. In the liquid crystal alignment treatment agent of the present invention Is preferably used.

The drying step after the application of the liquid crystal alignment treatment agent is not necessarily required, but it is preferable that the time from the application to the firing is not constant for each substrate, and the drying step is not included immediately after the application. 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. 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.

The firing of the substrate to which the liquid crystal alignment treatment agent is applied is preferably performed at an arbitrary temperature of 100 to 350 캜, more preferably 150 to 300 캜, still more preferably 180 to 250 캜. When an amic acid group is present in the liquid crystal alignment treatment agent, the conversion rate from amic acid to imide is changed by this firing. However, 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.

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

The substrate to which the liquid crystal alignment film obtained by the above method is attached can be made into a liquid crystal cell by a known method. For example, a pair of substrates on which a liquid crystal alignment film is formed is laminated with a spacer having a rubbing direction of 0 to 270 占 preferably between 1 and 30 占 퐉, more preferably between 2 and 10 占 퐉, It is common to provide an angle so that 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, a dropping (ODF) method in which a liquid crystal is dropped and then sealing is performed.

The liquid crystal display element obtained in this way can be used in various methods such as a TN liquid crystal display element, an STN liquid crystal display element, a TFT liquid crystal display element, an OCB liquid crystal display element, further, a transverse electric field type (IPS) liquid crystal display element, Is preferably used for a display element by

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.

(Synthesis Example 1)

Synthesis of 3,5-diaminobenzyl benzoate

In a 500 ml four-necked flask, 8.8 g of pyridine was added dropwise to a solution of 20.0 g of 3,5-dinitrobenzyl alcohol, 14.9 g of benzoyl chloride and 150 ml of tetrahydrofuran, and the mixture was stirred at room temperature for 30 hours. After completion of the reaction, pure water (50 ml) was added and the mixture was stirred for 1 hour. Ethyl acetate was added to extract the organic layer, and the organic layer was washed with 1N hydrochloric acid, saturated sodium hydrogencarbonate, and saturated saline. Anhydrous magnesium sulfate was added to the organic layer, followed by dehydration drying and filtration, followed by solvent distillation using a rotary evaporator. The residue was recrystallized from ethyl acetate to obtain 24.9 g of a dinitro compound having the following NMR characteristics (yield: 82%).

[Chemical Formula 17]

24.9 g of a dinitro compound, 2.5 g of platinum / carbon and 250 g of 1,4-dioxane were added to a 500 ml four-necked flask, and the mixture was stirred at room temperature under a hydrogen atmosphere. After completion of the reaction, the reaction mixture was subjected to Celite filtration, and solvent distillation was carried out using a rotary evaporator. The residue was recrystallized using methanol to obtain 12.8 g (yield 64%) of a pale brown solid.

The result of measurement of this pale brown solid by NMR is shown below. From the results, it was confirmed that the obtained pale brown solid was the intended diamine compound.

[Chemical Formula 18]

(Synthesis Example 2)

Synthesis of 3,5-diaminobenzylnicotinate

In a 500 ml three-necked flask, 25.0 g of 1,3-dinitrobenzyl alcohol, 24.6 g of picolinic acid chloride hydrochloride, 1.4 g of N, N-dimethylaminopyridine and 300 ml of tetrahydrofuran were added. 52.8 ml of triethylamine was added dropwise, and the mixture was stirred at room temperature for 18 hours. After completion of the reaction, pure water (50 ml) was added and the mixture was stirred for 1 hour. Ethyl acetate was added to extract the organic layer, and the organic layer was washed with 1N hydrochloric acid, saturated sodium hydrogencarbonate, and saturated saline. Anhydrous magnesium sulfate was added to the organic layer, followed by dehydration drying and filtration, followed by solvent distillation using a rotary evaporator. The residue was recrystallized using tetrahydrofuran / hexane = 1/4 to obtain 36.0 g of a dinitro compound having the following NMR characteristics (yield: 94%).

[Chemical Formula 19]

29.4 g of a dinitro compound, 4.5 g of platinum / carbon and 430 g of 1,4-dioxane were added to a 500 ml four-necked flask, and the mixture was stirred at room temperature under a hydrogen atmosphere. After completion of the reaction, the reaction mixture was subjected to Celite filtration, and solvent distillation was carried out using a rotary evaporator. The residue was recrystallized using isopropyl alcohol to give 20.2 g (yield: 86%) of a pale brown solid.

The result of measurement of this pale brown solid by NMR is shown below. From the results, it was confirmed that the obtained pale brown solid was a desired diamine compound.

[Chemical Formula 20]

(Synthesis Example 3)

Synthesis of 3,5-diaminobenzyl-1,3,4-trimethylpyrazole-5-carboxylate

17.1 g of 1,3,4-trimethyl-1H-pyrazole-5-carboxylic acid and 250 ml of dichloromethane were added to a 500 ml four-necked flask, and the mixture was cooled to 0 ° C. 10.2 ml of dichloromethane and 0.8 g of DMF were added, and the mixture was stirred at room temperature for 2 hours. After stirring, 22.0 g of 3,5-dinitrobenzyl alcohol and 9.7 g of pyridine were added, and the mixture was stirred at room temperature for 41 hours. After completion of the reaction, pure water (50 ml) was added and the mixture was stirred for 1 hour. Ethyl acetate was added to extract the organic layer, and the organic layer was washed with 1N hydrochloric acid, saturated sodium hydrogencarbonate, and saturated saline. Anhydrous magnesium sulfate was added to the organic layer, followed by dehydration drying and filtration, followed by solvent distillation using a rotary evaporator. Recrystallization of the residue using isopropyl alcohol gave 18.1 g of a dinitro compound having the following NMR characteristics (yield: 71%).

[Chemical Formula 21]

18.0 g of a dinitro compound, 1.8 g of platinum / carbon and 180 g of tetrahydrofuran were added to a 500 ml four-necked flask, and the mixture was stirred under a hydrogen atmosphere for 17 hours. After completion of the reaction, the reaction mixture was subjected to Celite filtration, and solvent distillation was carried out using a rotary evaporator. The residue was recrystallized using tetrahydrofuran and isopropyl alcohol to give 9.8 g (yield 67%) as a pale brown solid.

The result of measurement of this pale brown solid by NMR is shown below. From this result, it was confirmed that the obtained pale brown solid was the desired diamine compound.

[Chemical Formula 22]

(Synthesis Example 4)

Synthesis of 2- (pyridin-2-yl) ethyl-3,5-diaminobenzoate

In a 300 ml four-necked flask, 23.45 g of 2-pyridine ethanol and 19.23 g of triethylamine were dissolved in 200 ml of tetrahydrofuran, cooled to 10 占 폚 or lower, and 41.68 g of dinitrobenzoyl chloride was dissolved in 110 g of tetrahydrofuran The solution was added dropwise with caution to heat generation. After completion of the dropwise addition, the reaction temperature was raised to 23 DEG C and the reaction was carried out again. After confirming the completion of the reaction, the reaction solution was poured into 1.5 L of distilled water. The precipitated solid was filtered, washed with water and dispersed and washed with 380 g of ethanol to obtain 50.82 g of a dinitro compound having the following NMR characteristics (yield: 89% ).

(23)

48.00 g of dinitro compound, 4.8 g of platinum carbon and 490 g of 1,4-dioxane was stirred at 23 占 폚 in a hydrogen atmosphere. After completion of the reaction, the catalyst was filtered through celite, and the solvent was distilled off using this separator to obtain crude product.

The obtained crude product was dispersed and washed with 300 g of ethanol to obtain a desired diamine compound having the following NMR characteristics (Yield: 27.20 g, yield: 70%).

&Lt; EMI ID =

Examples 1 to 10 and Comparative Examples 1 to 4

In the following Examples 1 to 10 and Comparative Examples 1 to 4, production examples of a liquid crystal alignment treatment agent are described. Descriptions of abbreviations used in the synthesis of polyamic acid and polyimide are as follows, (Evaluation of rubbing resistance), &lt; Production of liquid crystal cell &gt;, &lt; Evaluation of pretilt angle &gt;, &lt; Evaluation method of voltage holding ratio &gt; The method for> is as follows.

The physical properties (properties) of each of the liquid crystal alignment treatment agents in Examples and Comparative Examples are summarized in Tables 1 and 2 below.

&Lt; Tetracarboxylic acid dianhydride &gt;

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

<Diamine>

DABPh: 3,5-diaminobenzyl benzoate

DABPy: 3,5-diaminobenzylnicotinate

DABTMPz: 3,5-diaminobenzyl-1,3,4-trimethyl-1H-pyrazole-5-carboxylate

RefDA: 2- (pyridin-2-yl) ethyl 3,5-diaminobenzoate

C14DAB: 4-tetradecyloxy-1,3-diaminobenzene

3-ABA: 3-aminobenzylamine

<Organic solvent>

NMP: N-methyl-2-pyrrolidone

? BL:? -butyrolactone

BC: butyl cellosolve

DPM: dipropylene glycol monomethyl ether

&Lt; Measurement of molecular weight &

The molecular weights of the polyamic acid and the polyimide were measured by a GPC (room temperature gel permeation chromatography) apparatus as described below, and the number average molecular weight and the weight average molecular weight were calculated using polyethylene glycol and polyethylene oxide conversion values, respectively.

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

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

Column temperature: 50 ° C

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

Flow rate: 1.0 ml / min

Standard sample for preparing a calibration curve: TSK standard polyethylene oxide (number 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 determined by dissolving the polyimide in d6-DMSO (dimethylsulfoxide-d6) and measuring 1 H-NMR to determine the ratio of the remaining amidic acid groups remaining imidized to the cumulative value of the proton peaks And calculated from the rain.

<Evaluation of rubbing resistance>

Each liquid crystal alignment treatment agent was spin-coated on a glass substrate with a transparent electrode, dried on a hot plate at 80 DEG C for 5 minutes, and then fired on a hot plate at 210 DEG C for 10 minutes to form a coating film having a film thickness of 70 nm . The coated surface was coated with a rayon cloth at a roll rotation speed of 1000 rpm, a roll advancing speed of 50 mm / sec, and an indentation amount of 0.5 mm with a rubbing apparatus (RSU-2 type manufactured by Inuma Gage Manufacturing Co., Ltd.) having a roll diameter of 120 mm Rubbed to obtain a substrate having a liquid crystal alignment film attached thereto. The surface of the liquid crystal alignment layer was observed with a confocal laser microscope. The evaluation was made according to the following criteria.

○: no scraping or rubbing damage was observed.

DELTA: scraping residue or rubbing damage is observed.

X: The film was peeled off or rubbing damage was visually observed.

&Lt; Production of liquid crystal cell &

Using each liquid crystal alignment treatment agent, a liquid crystal cell was produced as follows.

The liquid crystal alignment treatment agent was spin-coated on a glass substrate with a transparent electrode and dried on a hot plate at 80 DEG C for 5 minutes and then fired on a hot plate at 210 DEG C for 10 minutes to form a coating film having a film thickness of 70 nm . The coating film surface was rubbed with a rubbing apparatus having a roll diameter of 120 mm under the conditions of 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 with a liquid crystal alignment film attached . Two substrates each having a liquid crystal alignment film attached thereto were prepared. A spacer of 6 mu m was dispersed on the liquid crystal alignment film surface. Then, a sealant was printed thereon, and one substrate was faced with the liquid crystal alignment film face So that the direction of rubbing was orthogonal to each other. Thereafter, the sealing agent was cured to prepare an empty cell. A liquid crystal MLC-2003 (manufactured by Merck Japan Co.) was injected into this empty cell by a vacuum injection method, and the injection port was sealed to obtain a twisted nematic liquid crystal cell.

&Lt; Measurement of pretilt angle &gt;

The twisted nematic liquid crystal cell manufactured by the method described in &lt; liquid crystal cell production &gt; was heated at 105 DEG C for 5 minutes, and the pretilt angle was measured and the voltage holding ratio was measured. The pretilt angle was measured by a crystal rotation method.

&Lt; Measurement of voltage holding ratio &

A voltage of 4 V was applied for 60 seconds to a twisted nematic liquid crystal cell manufactured by the method described in &lt; liquid crystal cell production &gt;, and the voltage was measured after 16.67 ms. Was obtained as the voltage holding ratio. In addition, a voltage holding ratio measuring apparatus (VHR-1, manufactured by Toyota Technica Co., Ltd.) was used for measurement of the voltage holding ratio.

&Lt; Evaluation of accumulated charge (RDC) &gt;

A DC voltage was applied from 0 V to 0.1 V at intervals of 0.1 V to a twisted nematic liquid crystal cell manufactured by the method described in &lt; liquid crystal cell production &gt;, and the flicker amplitude level at each voltage was measured , And a calibration curve was prepared. Subsequently, after grounding for 5 minutes, an AC voltage of 3.0 V and a DC voltage of 5.0 V were applied. The flicker amplitude level after 1 hour was measured, and the RDC was evaluated by contrast with a calibration curve prepared in advance. The evaluation method of this RDC is called Flicker Reference Method.

(Example 1)

5.00 g (25 mmol) of CBDA as a tetracarboxylic acid dianhydride component and 6.30 g (26 mmol) of DABPh as a diamine component were reacted in 45.18 g of NMP at room temperature for 16 hours to obtain a 20 mass% To obtain a mixed acid solution (PAA-1).

10.0 g of the polyamic acid solution (PAA-1) was diluted with 13.3 g of NMP and 10.0 g of BC to obtain a liquid crystal composition comprising a solution containing 6 mass% of solids, 64 mass% of NMP, and 30 mass% of BC To obtain an orientation treatment agent.

(Example 2)

To 40 g of the polyamic acid solution (PAA-1 concentration 20 mass%) obtained in Example 1, 93.33 g of NMP was added and diluted. Then, 5.64 g of acetic anhydride and 2.33 g of pyridine were added and the mixture was reacted at 40 占 폚 for 3 hours Imidated. The reaction solution was cooled to room temperature, and then poured into 500 ml of methanol, and the precipitated solid was recovered. Further, this solid was washed several times with methanol, and then dried under reduced pressure at 100 占 폚 to obtain a white powder of polyimide (SPI-1). The polyimide had a number average molecular weight of 14,630, a weight average molecular weight of 32,160, and an imidization ratio of 82%.

To 2.00 g of the obtained polyimide (SPI-1), 18.0 g of? -BL was added and the mixture was stirred at 50 占 폚 for 20 hours. At the end of stirring, the polyimide completely dissolved. To this solution, 8.0 g of? -BL, 6.00 g of BC and 6.00 g of DPM were added and the mixture was stirred at 50 占 폚 for 20 hours to give 5 mass% of polyimide (SPI-1), 65 mass% of γ- , 15 mass%, and 15 mass% of BC, was obtained.

(Example 3)

, 5.00 g (25 mmol) of CBDA as a tetracarboxylic acid dianhydride component and 6.32 g (26 mmol) of DABPy as a diamine component were reacted in 45.29 g of NMP at room temperature for 16 hours to obtain a 20 mass% To obtain a polyamic acid solution (PAA-2).

10.0 g of the polyamic acid solution (PAA-2) was diluted with 13.3 g of NMP and 10.0 g of BC, and the liquid crystal alignment was carried out using a solution containing 6 mass% of solids, 64 mass% of NMP and 30 mass% of BC To obtain a treating agent.

(Example 4)

To 40 g of the polyamic acid solution (PAA-2 concentration 20 mass%) obtained in Example 3, 93.33 g of NMP was added and diluted, and 5.77 g of acetic anhydride and 2.39 g of pyridine were added and reacted at 40 DEG C for 3 hours to imidize did. The reaction solution was cooled to room temperature, and then poured into 500 ml of methanol, and the precipitated solid was recovered. Further, this solid was washed several times with methanol, and then dried under reduced pressure at 100 ° C to obtain a white powder of polyimide (SPI-2). The polyimide had a number average molecular weight of 13,204 and a weight average molecular weight of 30,700. The imidization rate was 87%.

18.0 g of? -BL was added to 2.00 g of the obtained polyimide (SPI-2), and the mixture was stirred at 50 占 폚 for 20 hours. At the end of stirring, the polyimide completely dissolved. To this solution were further added 8.0 g of? -BL, 6.00 g of BC and 6.00 g of DPM and the mixture was stirred at 50 占 폚 for 20 hours to obtain a mixture of 5 mass% of polyimide (SPI-2), 65 mass% of γ- , 15 mass%, and 15 mass% of BC, was obtained.

(Example 5)

5.30 g (27 mmol) of CBDA as a tetracarboxylic acid dianhydride component, 2.00 g (8 mmol) of DABPh as a diamine component, 1.35 g (11 mmol) of 3-ABA and 2.65 g mole) was reacted in 45.25 g of NMP at room temperature for 16 hours to obtain a 20 mass% polyamic acid solution (PAA-3).

10.0 g of the polyamic acid solution (PAA-3) was diluted with 13.3 g of NMP and 10.0 g of BC to obtain a liquid crystal alignment composed of a solution containing 6 mass% of solids, 64 mass% of NMP, and 30 mass% of BC To obtain a treating agent.

(Example 6)

To 40 g of the polyamic acid solution (PAA-3 concentration 20% by mass) obtained in Example 5, 93.33 g of NMP was added and diluted. 5.97 g of acetic anhydride and 2.47 g of pyridine were added and reacted at 60 ° C for 3 hours to imidize did. The reaction solution was cooled to room temperature, and then poured into 500 ml of methanol, and the precipitated solid was recovered. Further, this solid was washed several times with methanol, and then dried under reduced pressure at 100 占 폚 to obtain milky white powder of polyimide (SPI-3). The polyimide had a number average molecular weight of 14,785 and a weight average molecular weight of 37,483. The imidization rate was 88%.

18.0 g of? -BL was added to 2.00 g of polyimide (SPI-3), and the mixture was stirred at 50 占 폚 for 20 hours. At the end of stirring, the polyimide completely dissolved. 8.0 g of? -BL, 6.00 g of BC and 6.00 g of DPM were added to this solution, and the mixture was stirred at 50 占 폚 for 20 hours to obtain a solution containing 5 mass% of polyimide (SPI-3), 65 mass% A liquid crystal alignment treatment agent comprising a solution containing 15 mass% of DPM and 15 mass% of BC was obtained.

(Example 7)

5.27 g (27 mmol) of CBDA as a tetracarboxylic acid dianhydride component, 2.00 g (8 mmol) of DABPy as a diamine component, 1.34 g (11 mmol) of 3-ABA and 2.63 g m mol), and reacted in 44.96 g of NMP at room temperature for 16 hours to obtain a 20 mass% polyamic acid solution (PAA-4).

10.0 g of the polyamic acid solution (PAA-4) was diluted with 13.3 g of NMP and 10.0 g of BC, and the liquid crystal alignment made of a solution containing 6 mass% of solids, 64 mass% of NMP and 30 mass% of BC To obtain a treating agent.

(Example 8)

To 40 g of the polyamic acid solution (PAA-4 concentration 20% by mass) obtained in Example 7, 93.33 g of NMP was added and diluted. 5.97 g of acetic anhydride and 2.47 g of pyridine were added and reacted at 60 DEG C for 3 hours to imidize did. The reaction solution was cooled to room temperature, and then poured into 500 ml of methanol, and the precipitated solid was recovered. Further, this solid was washed several times with methanol, and then dried under reduced pressure at 100 占 폚 to obtain milky white powder of polyimide (SPI-4). This polyimide had a number average molecular weight of 15,594 and a weight average molecular weight of 42,320. The imidization rate was 87%.

18.0 g of? -BL was added to 2.00 g of polyimide (SPI-4), and the mixture was stirred at 50 占 폚 for 20 hours. At the end of stirring, the polyimide completely dissolved. Further, 8.0 g of? -BL, 6.00 g of BC and 6.00 g of DPM were added to this solution and the mixture was stirred at 50 占 폚 for 20 hours to obtain a solution of 5% by mass of polyimide (SPI-4), 65% A liquid crystal alignment treatment agent comprising a solution containing 15 mass% of DPM and 15 mass% of BC was obtained.

(Example 9)

5.57 g (29 mmol) of CBDA as a tetracarboxylic acid dianhydride component, 2.38 g (9 mmol) of DABTMPz as a diamine component, 1.42 g (12 mmol) of 3-ABA and 2.79 g moles) and reacted in 46.7 g of NMP at room temperature for 16 hours to obtain a solution having a concentration of polyamic acid (PAA-5) of 20 mass%.

10.0 g of this polyamic acid (PAA-5) solution was diluted with 13.3 g of NMP and 10.0 g of BC, and 6 mass% of polyamic acid (PAA-5), 64 mass% of NMP and 30 mass% To obtain a liquid crystal alignment treatment agent.

(Example 10)

To 40.0 g of the polyamic acid (PAA-5 concentration 20% by mass) obtained in the same manner as in Example 9, 93.3 g of NMP was added and diluted, and 6.06 g of acetic anhydride and 2.53 g of pyridine were added thereto to obtain 60 Lt; RTI ID = 0.0 &gt; C &lt; / RTI &gt; for 3 hours. The reaction solution was cooled to room temperature, and then poured into 500 ml of methanol, and the precipitated solid was recovered. Further, this solid was washed twice with methanol, and then dried under reduced pressure at 100 占 폚 to obtain a white-brown powder of polyimide (SPI-5). The polyimide had a number average molecular weight of 14,222 and a weight average molecular weight of 33,154. The imidization rate was 88%.

18.0 g of? -BL was added to 2.00 g of polyimide (SPI-5), and the mixture was stirred at 50 占 폚 for 20 hours. At the end of stirring, the polyimide completely dissolved. Further, 8.00 g of? -BL, 6.00 g of BC and 6.00 g of DPM were added to this solution, and the mixture was stirred at 50 占 폚 for 20 hours to give 5 mass% of polyimide (SPI-5), 65 mass% A liquid crystal alignment treatment agent comprising a solution containing 15 mass% of DPM and 15 mass% of BC was obtained.

(Comparative Example 1)

12.5 g (64 mmol) of CBDA as a tetracarboxylic acid dianhydride component, 5.56 g (46 mmol) of 3-ABA as a diamine component and 6.25 g (20 mmol) of C14 DAB were used, And reacted at room temperature for 16 hours to obtain a 20 mass% polyamic acid solution (PAA-6).

10.0 g of polyamic acid (PAA-6) was diluted with 13.3 g of NMP and 10.0 g of BC to obtain a liquid crystal alignment treatment agent (liquid crystal alignment treatment agent) comprising a solution containing 6% by mass of solid content, 64% by mass of NMP, and 30% .

(Comparative Example 2)

To 50 g of the polyamic acid solution (PAA-6) obtained in Comparative Example 1, 116.67 g of NMP was added and diluted. 7.39 g of acetic anhydride and 3.15 g of pyridine were added and the mixture was reacted at 70 DEG C for 3 hours to effect imidization. .

To 50 g of the polyamic acid solution (PAA-6) again, 116.67 g of NMP was added and diluted, and 7.39 g of acetic anhydride and 3.15 g of pyridine were added, and the imidization reaction temperature was set to 50 캜.

The reaction solution was cooled to room temperature and then poured into 600 ml of methanol, and the precipitated solid was recovered. Further, this solid was washed several times with methanol, and then dried under reduced pressure at 100 占 폚 to obtain a white powder of polyimide (SPI-6). This polyimide had a number average molecular weight of 16,338 and a weight average molecular weight of 39,865. The imidization rate was 80%.

9 g of? BL was added to 1.00 g of polyimide (SPI-6), and the mixture was stirred at 50 占 폚 for 20 hours. At the end of stirring, the polyimide completely dissolved. Further, 4.0 g of? -BL, 3.0 g of BC and 3.0 g of DPM were added to this solution and stirred at 50 占 폚 for 20 hours to obtain polyimide of 5% by mass,? -BL of 65% by mass, DPM of 15% , And a solution containing 15 mass% of BC.

(Comparative Example 3)

5.96 g (29 mmol) of CBDA as a tetracarboxylic acid dianhydride component, 2.31 g (9 mmol) of RefDA as a diamine component, 1.46 g (12 mmol) of 3-ABA and 2.88 g mmol) was reacted in 56.84 g of NMP at room temperature for 16 hours to obtain a 20 mass% polyamic acid solution (PAA-7).

10.0 g of polyamic acid (PAA-7) was diluted with 13.3 g of NMP and 10.0 g of BC to prepare a liquid crystal alignment treatment agent (liquid crystal alignment treatment agent) comprising a solution containing 6% by mass of solids, 64% by mass of NMP, and 30% .

(Comparative Example 4)

To 50 g of the polyamic acid solution (PAA-7) obtained in Comparative Example 3, 116.67 g of NMP was added and diluted. 7.39 g of acetic anhydride and 3.06 g of pyridine were added and reacted at 70 캜 for 3 hours for imidization.

The reaction solution was cooled to room temperature and then poured into 600 ml of methanol, and the precipitated solid was recovered. Further, this solid was washed with methanol several times, and then dried under reduced pressure at 100 ° C to obtain a pale brown powder of polyimide (SPI-7). The polyimide had a number average molecular weight of 18,668 and a weight average molecular weight of 41,256. The imidization ratio was 89%.

9 g of? BL was added to 1.00 g of polyimide (SPI-7), and the mixture was stirred at 50 占 폚 for 20 hours. At the end of stirring, the polyimide completely dissolved. Further, 4.0 g of? -BL, 3.0 g of BC and 3.0 g of DPM were added to this solution and the mixture was stirred at 50 占 폚 for 20 hours to obtain polyimide at 5 mass%,? -BL at 65 mass%, DPM at 15 mass% , And a solution containing 15 mass% of BC.

Industrial availability

The liquid crystal alignment treatment agent of the present invention can provide a liquid crystal alignment film that is resistant to film peeling and scoring during rubbing, has a high voltage holding ratio, and is less prone to accumulation of initial charge even when a direct current voltage is applied. 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 TN liquid crystal display device, STN liquid crystal display device, TFT liquid crystal display device, VA liquid crystal display device, An IPS liquid crystal display element, an OCB liquid crystal display element, and the like.

The entire contents of the specification, claims, and abstract of Japanese Patent Application No. 2009-283330 filed on December 14, 2009 are hereby incorporated herein by reference as the disclosure of the specification of the present invention.

Claims (19)

At least one member selected from the group consisting of a polyamic acid obtained by reacting a diamine component containing a diamine compound represented by the following formula [1] with a tetracarboxylic acid dianhydride component, and a polyimide obtained by imidizing the polyamic acid Of a polymer.

Wherein Ar represents a heterocyclic aromatic compound or a nitrogen atom-containing heterocyclic aromatic compound and the hydrogen atom on the carbon atom or nitrogen atom constituting the ring is a methyl group, an ethyl group, a methoxy group, an ethoxy group, an amino group, , A carboxyl group, a nitro group or a cyano group) The method according to claim 1,
Wherein Ar in formula [1] is a heterocyclic aromatic compound having 6 atomic rings or a nitrogen atom-containing heterocyclic aromatic compound having 6 atomic rings. The method according to claim 1,
Wherein Ar in formula [1] is a nitrogen atom-containing heterocyclic aromatic compound having five atomic rings. The method according to claim 1,
Wherein Ar in the formula [1] is benzene, pyridine, pyridazine, pyrimidine, pyrazine or triazine. The method according to claim 1,
A liquid crystal alignment treatment agent wherein Ar in formula [1] is oxazole, oxadiazole, thiazole, thiadiazole, pyrrole, imidazole, pyrazole, or triazole. The method according to claim 1,
A liquid crystal alignment treatment agent wherein the diamine compound represented by the formula [1] is any of the compounds represented by the following formulas [4] to [6].

The method according to claim 1,
A liquid crystal alignment treatment agent wherein the diamine compound represented by the formula [1] is a compound represented by the following formula [2].

8. The method according to any one of claims 1 to 7,
A liquid crystal alignment treatment agent containing at least 10 mol% of a diamine compound represented by the following formula [3] as a diamine component.
H ₂ N-Ar'-R ₁ -NH-R ₂ [3]
(Wherein Ar 'represents a phenylene group or a naphthylene group, R ₁ Represents an alkylene group having 1 to 5 carbon atoms, and R &lt; ₂ &gt; Represents an alkyl group having 1 to 5 carbon atoms) 8. The method according to any one of claims 1 to 7,
Wherein the tetracarboxylic acid dianhydride component comprises a tetracarboxylic acid dianhydride having an alicyclic structure or an aliphatic structure. A liquid crystal alignment film formed by applying the liquid crystal alignment treatment agent according to any one of claims 1 to 7 onto a substrate having electrodes attached thereto and firing the liquid crystal alignment treatment agent. 11. A liquid crystal display element comprising the liquid crystal alignment film according to claim 10. A diamine compound represented by the following formula [1].

Wherein Ar represents a heterocyclic aromatic compound or a nitrogen atom-containing heterocyclic aromatic compound and the hydrogen atom on the carbon atom or nitrogen atom constituting the ring is a methyl group, an ethyl group, a methoxy group, an ethoxy group, an amino group, , A carboxyl group, a nitro group or a cyano group) 13. The method of claim 12,
A diamine compound represented by the formula [1] wherein Ar is an aromatic ring compound having 6 atoms or an aromatic heterocyclic compound containing 6 atoms. 13. The method of claim 12,
A diamine compound of the formula [1] wherein Ar is a heterocyclic aromatic compound containing a nitrogen atom in a five-membered ring. 13. The method of claim 12,
Wherein Ar of formula [1] is benzene, pyridine, pyridazine, pyrimidine, pyrazine or triazine. 13. The method of claim 12,
A diamine compound wherein Ar in formula [1] is an oxazole, oxadiazole, thiazole, thiadiazole, pyrrole, imidazole, pyrazole, or triazole. 13. The method of claim 12,
The diamine compound represented by the formula [1] is any of the compounds represented by the following formulas [4] to [6].

13. The method of claim 12,
The diamine compound represented by the formula [1] is a compound represented by the following formula [2].

A polyimide obtained by reacting a diamine component containing the diamine compound according to any one of claims 12 to 18 with a tetracarboxylic acid dianhydride component, or a polyimide obtained by imidizing the polyamic acid.