JPS62262829A - Composition for liquid crystal orientation treating agent - Google Patents

Abstract

PURPOSE:To obtain the titled composition capable of using for the orientation treating agent of the liquid crystal cell having a large tilt orientation angle of the liquid crystal by composed of at least one kind of a compd. selected from specific amine compds., and a precursor of a polyimide resin. CONSTITUTION:The titled composition is composed of at least one kind of the compd. selected from the amine compds. shown by formulas I and II, and the precursor of the polyimide resin shown by formula III. In the formulas I and II, R<1> is 6-20C hydrocarbon group, R<2> and R<3> are each the same or the different each other, and 4-20C the hydrocarbon. In formula III, R<4> is tetracarboxylic acid or 4-valent org. group capable of constituting its derivative, R<5> is bivalent org. group capable of constituting diamine, (n) is a positive integer. The concrete example of the amine compd. shown by formulas I and II is exemplified by n-hexylamine etc., and di-n-butylamine, etc.

Description

Detailed description of the invention (a) Industrial application field The present invention relates to a composition for a liquid crystal aligning agent,
More specifically, the present invention relates to a composition used as an alignment treatment agent for liquid crystal cells in which liquid crystal molecules have an increased tilted alignment angle with respect to a substrate.

(b) Conventional technology Organic resin films such as polyimide resin films have conventionally been used as substrate processing agents for aligning nematic liquid crystal molecules almost parallel to a transparent substrate such as glass or plastic film with transparent electrodes. Most commonly used.

In this case, each time the organic resin film formed on the substrate is rubbed in a certain direction with a cloth, the liquid crystal molecules are aligned in the rubbing direction, and at the same time, the liquid crystal tilt orientation angle is usually about 1 to 3 degrees with respect to the substrate surface. is known to occur.

Furthermore, as a method for greatly tilting liquid crystal molecules, a method has conventionally been used in which an inorganic film such as silicon oxide is deposited on a substrate.

(c) Problems to be Solved by the Invention With the method of rubbing an organic resin film formed on a substrate, it is difficult to align liquid crystal molecules with a large tilt.

Furthermore, the method of depositing an inorganic film on a substrate is more complicated than the rubbing method, and is not necessarily an appropriate method for actual industrial production.

(d) Means for Solving the Problems The present inventors have made extensive efforts to solve the above problems, and as a result have completed the present invention.

That is, the present invention provides R'-NH[I]NH(II) represented by the general formula [I] and the general formula (II) (wherein, R1 is a hydrocarbon group having 6 to 20 carbon atoms, RZ ,
R3 each represents a hydrocarbon group having 4 to 20 carbon atoms or different carbon atoms. ) At least one compound selected from amine compounds and represented by the general formula (III) (wherein R4 is a tetravalent organic group constituting a tetracarboxylic acid or its derivative, R5 is a divalent organic group constituting a diamine) The present invention relates to a composition for a liquid crystal aligning agent comprising an organic group (n is a positive integer) and a polyimide resin precursor.

The composition of the present invention is used as an alignment treatment agent for liquid crystal cells by coating it on a transparent substrate such as glass or plastic film with transparent electrodes, forming a polyimide resin film after curing, and then subjecting it to a rubbing treatment. be able to.

The organic group R1 of the amine compound of general formula [I] used in the composition of the present invention is a hydrocarbon group having 6 to 20 carbon atoms,
Examples include alkyl groups, nuclear-substituted or non-nuclear-substituted aryl groups, aralkyl groups, and cycloalkyl groups.

When the number of carbon atoms in the organic group R1 is 5 or less, the effect of increasing the tilt orientation angle of liquid crystal molecules is not sufficient.

Furthermore, if the number of carbon atoms exceeds 20, problems such as poor applicability to a substrate tend to occur.

Specific examples of the amine compound of general formula [I] include n-hexylamine, n-octylamine, n-decylamine, n-dodecylamine, n-hexadecylamine, 1,
3-dimethylbutylamine, 1,5-dimethylhexylamine, 2-ethylhexylamine, p-aminobiphenyl, p-aminoethylhensen, benzylamine, p
-Methylbenzylamine, 4-ethylcyclohexylamine, and the like.

Moreover, the organic groups R2 and R of the amine compound of general formula [II]
3 are the same or different hydrocarbon groups having 4 to 20 carbon atoms.

For the same reason as the amine compound of general formula C1) above, R
The number of carbon atoms in 2 and R3 is suitably in the range of 4 to 20, and examples of the hydrocarbon groups R2 and R3 include alkyl groups, nuclear-substituted or non-nuclear-substituted aryl groups, aralkyl groups, and cycloalkyl groups.

Specific examples of the amine compound of general formula C11) include di-n
-butylamine, di-butylamine, di-n-amylamine, di-myamylamine, di-n-hexylamine, di-n-octylamine, di-n-dodecylamine, di-n-hexadecylamine, -Hensylamine, diphenylamine, dicyclohexylamine and the like.

In addition, the polyimide resin precursor of the general formula [■] used in the composition of the present invention is represented by the general formula (rV) (wherein R4 represents a tetravalent organic group constituting a tetracarboxylic acid. , each of the four carbonyl groups bonded to R4 is directly bonded to a separate carbon atom.) One or more compounds selected from tetracarboxylic acids and derivatives thereof and represented by the general formula (V) HzN R5NHz (V) (In the formula, R5 represents a divalent organic group constituting the diamine.) It is obtained by reacting a diamine.

Specific examples of the tetracarboxylic acid of general formula (rV) and its derivatives include aromatic tetracarboxylic acids such as pyromellitic acid, benzophenonetetracarphonic acid, 3,4.3',4'-biphenyltetracarboxylic acid; These dianhydrides, these dicarboxylic acid halides, alicyclic tetracarboxylic acids such as cyclobutanetetracarboxylic acid, cyclopenkunetetracarboxylic acid, cyclohexanetetracarboxylic acid, these dianhydrides, and these dicarboxylic acids Examples include diacid halides, aliphatic tetracarboxylic acids such as butanetetracarboxylic acid, dianhydrides thereof, and diacid halides of these dicarboxylic acids.

Further, the te[-dicarboxylic acid of the general formula [■] and its derivatives may be used alone or in combination of two or more.

Specific examples of the amine of general formula (V) include p-phenylenediamine, m-phenylenediamine, diaminodiphenylmethane, diaminodiphenyl ether, 2,2-diaminodiphenylpropane, diaminodiphenylsulfone, diaminohensiphenone, diaminonaphthalene, 1
．． 3-bis(4-aminophenoxy)benzene, ■, 4
-bis(4-aminophenoxy)benzene, 4,4'-
Di(4-aminophenoxy)diphenylsulfone, 2.
2'-bis(4(4,-aminophenoxy)phenyl)
Examples include aromatic diamines such as propane.

Depending on the purpose, alicyclic diamines and aliphatic diamines may also be used.

Further, these diamines may be used alone or in combination of two or more.

The amine compounds of general formula [I] and general formula [II] of the composition of the present invention can be used individually or in a mixture of two or more.

The amount of the amine compound of general formula (T) and general formula (II) to be used is not particularly limited, but is preferably in the range of 1 to 100% by weight based on the polyimide resin precursor of general formula [■].

That is, within the above range, -i formula [I] and general formula (
The orientation angle of the liquid crystal molecules can be arbitrarily adjusted by adjusting the amount of the amine compound (Il) used.

- If the amount of the amine compound of general formula [I] or general formula (II) used is less than 1% by weight, the effect may not be sufficiently recognized, and if it exceeds 100% by weight, the applicability to the substrate will deteriorate. It becomes easier to control such inconveniences.

Solvents are used in preparing the compositions of the invention. These solvents are not particularly limited as long as they can dissolve the compounds of general formula [I] and general formula (n) and the polyimide resin precursor of general formula (III).

Specific examples of these solvents include N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, N-methylcaprolactam, dimethylsulfoxide, tetramethylurea, pyridine, dimethylsulfone, hexamethylphosphoramide. and butyshi 1 lactone.

These may be used alone or in combination.

Furthermore, even if a solvent cannot produce a homogeneous solution by itself,
The solvent may be used in addition to the above-mentioned solvents as long as a homogeneous solution can be obtained.

Moreover, the amount of the solvent used is determined according to the general formula [I] and the M formula (I
It is sufficient that the amine compound of I) (hereinafter simply referred to as amine compound) and the polyimide resin precursor of general formula [■] can be uniformly dissolved, and generally the amine compound and the polyimide resin precursor of general formula (III) 0.5 to 100 parts by weight is used per 1 part by weight of the total amount of polyimide resin precursor.

The composition of the present invention can be prepared by simultaneously dissolving the fll amine compound and the compound of general formula CI [1], (2)
) A method of adding and dissolving the amine compound after dissolving the compound of general formula [111) in a solvent, (3) A method of adding and dissolving the compound of general formula (III) after dissolving the amine compound in a solvent, (4) Amine compound and general formula CI
A method in which the compounds of II) are individually dissolved in a solvent and then mixed. (5) After producing the compound of the general formula [■], a method may be mentioned in which an amine compound or a solution thereof dissolved in a solvent is added.

The composition of the present invention can also be used as an alignment treatment agent for liquid crystal cells, and examples of the method include the following methods.

That is, after applying the composition of the present invention onto a transparent substrate such as a glass or plastic film with a transparent electrode by a spin code method or a printing method, the composition is heated at 150 to 250°C.
A polyimide resin film having a thickness of 200 to 3,000 thick is formed by curing for 1 minute to 2 hours, and then the polyimide resin film layer is subjected to a rubbing treatment to obtain an alignment treatment agent for liquid crystal cells.

(E) Effects of the Invention The composition of the present invention can be used as an alignment treatment agent for liquid crystal cells having a large liquid crystal tilt orientation angle.

In addition, the liquid crystal tilt orientation angle is expressed by the general formula [I] and the general formula [11
) can be arbitrarily adjusted by changing the amount of the amine compound used.

(f) Examples The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited thereto.

Example 1 N-hexadecylamine was added to a polyimide resin in a commercially available polyimide resin precursor solution [trade name: Sunever 130.15% by weight N-2-methylpyrrolidone (hereinafter abbreviated as NMP) solution] manufactured by Nichiwa Kagaku Kogyo ■. It was added to the precursor component in an amount of 10% by weight, and after diluting the total solid content to 2% by weight with NMP, it was sufficiently stirred to form a homogeneous solution.

This solution was spin-coded onto two glass substrates with transparent electrodes, and heat-treated at 170°C for 60 minutes, resulting in a thickness of 10 mm.
00 to 1500 polyimide resin coatings were formed.

After rubbing this coating film with a cloth, it is assembled with a 50μ spacer in between and the rubbing direction parallel to the LCD (BD)
E-7) manufactured by Company H was injected to create a homogeneously oriented cell.

When this cell was rotated in a crossed nicol, clear brightness and darkness were observed, confirming that it was well oriented in the rubbing direction.

Further, when the liquid crystal tilt orientation angle of this cell was measured using a magnetic field capacitance method, it was found to be 12°.

Example 2 The same process as in Example 1 was carried out except that n-hexadecylamine was replaced with n-octylamine. The liquid Z high tilt orientation angle was 6° and the orientation was good.

Example 3 The same process as in Example 1 was carried out except that the amount of n-hexadecylamine was 3% by weight based on the polyimide resin precursor, and the liquid crystal tilt orientation angle was 6° and the alignment was good.

Example 4 The same process as in Example 1 was performed except that the liquid crystal was changed to ZLI-2293 (manufactured by Merck & Co., Ltd.), and the liquid crystal tilt orientation angle was 15.
° and the orientation was also good.

Example 5 The same process as in Example 1 was performed except that a 6μ spacer was used, and the liquid crystal tilt orientation angle was 15° and the alignment was good.

Comparative Example When the same treatment as in Example 1 was performed except that n-hexadecylamine was not used, the liquid crystal tilt orientation angle was 2.4°.

Claims (1)

[Claims] 1. R^1 represented by general formula [I] and general formula [II]
-NH[I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼[II] (In the formula, R^1 is a hydrocarbon group with 6 to 20 carbon atoms, R^2
, R^3 each represent the same or different hydrocarbon groups having 4 to 20 carbon atoms. ) At least one compound selected from amine compounds and the general formula [III] ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [III] (In the formula, R^4 constitutes a tetracarboxylic acid or its derivative (R^5 is a divalent organic group constituting the diamine, n is a positive integer.) A composition for a liquid crystal aligning agent comprising a polyimide resin precursor. 2. Claim No. 1 in which R^1 of the amine compound represented by the general formula [I] is R^1=CH_3-(CH_2)_m (m is a positive integer of 5 to 19) The composition for a liquid crystal aligning agent according to item 1.