JPH01239526A - Composition for liquid crystal orientation film - Google Patents

Abstract

PURPOSE:To obtain a compsn. for liquid crystal orientation film having a large pretilt angle and useful characteristics for an SBE (Supertwisted Birefringency Effect) display element, by incorporating a polyamide deriv. and/or an imide type polymer, and a polyhydric alcohol deriv. into a compsn. for a liquid crystal orientation film. CONSTITUTION:A compsn. contg. a polyamide deriv. such as polyamide acid, polyamide acid ester, an imide type polymer such as polyimide, a polyamideimide, polyesterimide, etc. and a polyhydric alcohol deriv. is applied to above a pattern of a substrate and/or a transparent electrode, and a liquid crystal orientation film is obtd. by rubbing the coated material. Thus, a liquid crystal display element having superior contrast, dependency on visual angle, and a large pretilt angle, particularly, a liquid crystal display element useful as an SBE display element, is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a composition for a liquid crystal alignment film used in manufacturing a liquid crystal display element.

[Conventional technology]

Conventionally, a TN array cell is one in which a nematic liquid crystal with positive dielectric anisotropy is sandwiched between transparent electrodes coated with a liquid crystal alignment film so that the long axis of the liquid crystal molecules is continuously twisted by 90 degrees between the upper and lower substrates. A display element having (TN type display element)
It has been known.

This alignment state of liquid crystals can be achieved by rubbing a liquid crystal alignment film made of polyimide or the like coated on a transparent electrode in one direction with a roll wrapped with a cloth made of synthetic fiber. This can be achieved by incorporating the rubbing directions so that they are perpendicular to each other.

However, this TN type display element has problems with contrast and viewing angle dependence, and recently S B E (S
upper thisted Birefringenc
y Effect) display elements have become known.

This SBE display element uses a blend of nematic liquid crystal and a chiral agent, which is an optically active substance, as the liquid crystal, and the birefringence effect produced by continuously twisting the long axis of the liquid crystal molecules by more than 180 degrees between the upper and lower substrates. This is a display element that utilizes.

Conventionally, SBE display elements have been manufactured by using a substrate on which silicon dioxide is obliquely deposited in order to orient liquid crystals, but this method has problems in terms of display reproducibility and manufacturing process.

Furthermore, when this SBE display element is manufactured using polyimide as described above as a liquid crystal alignment film, the pretilt angle between the long axis of the aligned liquid crystal molecules and the liquid crystal alignment film is small, so that the liquid crystal is tilted by 180 degrees or more. It has the problem that it cannot be twisted, making it difficult to achieve the intended display function.

[Problem that the invention seeks to solve]

The present invention has been made against the background of such conventional technical problems, and is directed to a liquid crystal display element having a large pretilt angle, particularly an SBE.
It is an object of the present invention to provide a composition for a liquid crystal alignment film that is useful for manufacturing display elements.

[Means for solving problems]

The present invention provides a composition for a liquid crystal alignment film containing a polyamide derivative and/or an imide polymer and a polyhydric alcohol derivative.

In the present invention, polyamide derivatives such as polyamic acid and polyamic acid ester, and imide polymers such as polyimide, polyamide imide, and polyester imide are used, and among these, polyamic acid and polyimide are preferably used.

Here, the polyamic acids and polyamic acid esters (hereinafter referred to as "polyamic acids") used in the present invention are produced by, for example, aliphatic, alicyclic, or aromatic tetracarboxylic acids and diamines in an organic solvent. Obtained by reaction.

In the present invention, tetracarboxylic acids include tetracarboxylic acid, tetracarboxylic acid anhydride, tetracarboxylic dianhydride, tetracarboxylic acid monoalkyl ester, tetracarboxylic acid dialkyl ester, tetracarboxylic acid trialkyl ester, and It represents a tetracarboxylic acid tetraalkyl ester.

Examples of such tetracarboxylic acids include butanetetracarboxylic acids, 1,2,3,4-cyclobutanetetracarboxylic acids, 1,2,3,4-cyclopentanetetracarboxylic acids, and 2,3,5-1-ricarpoxycyclo Bentyl acetic acid, 3,5.6-dolycarpoxynorbornane-2-acetic acids, 5-(2,5-dioxotetrahydrofuryl)-3-methyl-cyclohexenedicarboxylic acids, bicycloC2,2,2)- Aliphatic or alicyclic tetracarboxylic acids such as octo-7-nin-tetracarboxylic acids, 1,2,3,4-furantetracarboxylic acids, 3.3', 4.4'-perfluoroisopropylidene tetracarboxylic acids Acid; 4,4'-bis(3,4-dicarboxyphenoxy)diphenyl sulfides, 4,4'-bis(3
, 4-dicarboxyphenoxy) diphenylsulfones, 4゜4'-bis(3,4-dicarboxyphenoxy)
diphenylpropanes, 3.3', 4.4'-perfluoroisopropylidenetetracarboxylic acids, 3.3',
4.4'-biphenyl ether lutetracarboxylic acids,
Bis(phthalic acid) phenylphosphine oxides, p
-phenylene-bis-(triphenylphthalic acid), m
-Phenylene-bis-(triphenylphthalic acid) R, bis(triphenylphthalic acid)-4,4'-diphenyl ethers, bis(triphenylphthalic acid)-4,4'-
Diphenylmethanes, pyromellitic acids, 3.3'.

4.4'-benzophenonetetracarboxylic acids, 3.3
', 4.4'-biphenylsulfonetetracarboxylic acids, 1, 4.5.8-naphthalenetetracarboxylic acids, 2
, 3,6.7-naphthalenetetracarboxylic acids, 3.3
Aromatic compounds such as ', 4.4'-biphenyl ether tetracarboxylic acids, 3.3', 4゜4'-dimethyldiphenylsilane tetracarboxylic acids, 3.3', 4.4'-tetraphenylsilane tetracarboxylic acids, etc. Tetracarboxylic acids can be mentioned.

Among these tetracarboxylic acids, preferred are aliphatic or alicyclic tetracarboxylic acids, particularly preferred are 2,3.5=tricarboxycyclopentyl acetic acids, 1,2゜3.4-cyclo Pentanetetracarboxylic acids, preferably 50% by weight or more, particularly preferably 75% by weight as tetracarboxylic acids.
Polyamic acids containing at least % by weight are most preferred.

In addition, examples of diamines to be reacted with the tetracarboxylic acids include phenylenediamine, metaphenylenediamine, 4.4'-diaminodiphenylmethane, 4.4'
-Diaminodiphenylethane, benzidine, 4.4'-
Diaminodiphenylsulfide, 4,4'-diaminodiphenylsulfone, 4,4'-diaminodiphenyl ether, 1,5-diaminonaphthalene, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,4'-diaminobenz Anilide, 3,4'-diaminodiphenyl ether, 3,3'-diaminohensiphenone, 3,4'-
Diaminobenzophenone, 4゜4'-diaminobenzophenone, 2,2-bis(4-(4-aminophenoxy)
phenyl]propane, bis(4-(4-aminophenoxy)phenyl)sulfone, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,3-bis(3 -aminophenoxy)benzene, 9,9-bis(4-aminophenyl)-1
O-hydro-anthracene, 9゜9-bis(4-aminophenyl)fluorene, 4゜4'-methylene-bis(2
-chloroaniline), 2.2', 5.5'-tetrachloro-4,4'-diaminobiphenyl, 2.2'-dichloro-4°4-diamino-5,5'-dimethoxybiphenyl, 3.3 Aromatic diamines such as '-dimethoxy-4,4'-diaminobiphenyl, 1,1'-methaxylylene diamine, 1,3-propanediamine, tetramethylene diamine, pentamethylene diamine, hexamethylene diamine, heptamethylene diamine, Octamethylene diamine, nonamethylene diamine, 4,4'-dimethylhebutamethylene diamine, 1,4-diaminocyclohexane, isophorone diamine, tetrahydrodicyclopentadienylene diamine, hexahydro-4,7-methanoindanilene shimethylene diamine , tricyclo(6,2,l
, O”°7]-Aliphatic or alicyclic diamine such as undecylendimethyldiamine, O (wherein R is an alkyl group having 1 to 12 carbon atoms such as a methyl group, an ethyl group, a propyl group, a cyclohexyl group, etc.) an alicyclic group, or an aromatic group such as a phenyl group, m is an integer of 1 to 3, n is 1 to 2
Examples include diaminoorganosiloxanes represented by the following formulas (indicating an integer of o).

These tetracarvone fII! and diamine can be used alone or in combination of two or more.

The proportion of diamine used in the production of polyamic acids is usually 0.5 per mole of tetracarboxylic acids.
-2.0 mol, preferably 0.8-1.3 mol.

Further, as the organic solvent that can be used in the production of polyamic acids, any organic solvent that can dissolve the obtained polyamic acids (for example, N-methyl-2-pyrrolidone,
Aprotic polar solvents such as N,N-dimethylacetamide, N,N-dimethylformamide, dimethylsulfoxide, T-butyrolactone, tetramethylurea, hexamethylphosphortriamide, m-cresol, xylenol, phenol, halogenated phenol, etc. Examples include phenolic solvents.

The amount of this organic solvent used is not particularly limited, but the solid content concentration is usually 0.1 to 30% by weight, preferably 0.5 to 2% by weight.
The amount is such that the amount is 0% by weight.

The reaction temperature when synthesizing polyamic acids is usually 50 to 50,000, for example, when the tetracarboxylic acids are monoalkyl esters, dialkyl esters, trialkyl esters, tetraalkyl esters, and monoanhydrides of tetracarboxylic acids and nucleic acids. 250℃, preferably 70-2
The temperature is 30°C.

Moreover, when the tetracarboxylic acid is a tetracarboxylic dianhydride, the reaction is usually carried out at 0 to 100°C.

In addition, as the polyimide, polyimide obtained by heating the polyamic acid at 50 to 300°C, preferably 80 to 160°C to cause dehydration and ring closure is preferable; It may also be a polyimide in which a polyamide unit and a polyimide unit coexist, that is, a poly(amide-imide) in which a dehydration ring-closing reaction has been partially performed.

The reaction for synthesizing polyimide from polyamide acids is usually carried out in an organic solvent using a reaction catalyst, such as an organic amine compound such as triethylamine, pyridine, lutidine, or collidine; or an acid anhydride such as acetic anhydride, propionic anhydride, or trifluoroacetic anhydride. Perform in the presence of an object.

Furthermore, the polyimide includes not only the polyimide synthesized from the above-mentioned polyamide acids but also the polyimide synthesized from diisocyanate and tetracarboxylic acids.

Here, as the diisocyanate, for example, 2゜4-tolylene diisocyanate, 2,6-1-lylene diisocyanate, p-phenylene diisocyanate, m-phenylene diisocyanate, 4゜4'-diphenylmethane diisocyanate, 4゜4'-diphenyl diisocyanate, Nylether diisocyanate, 4゜4'-diphenylsulfone diisocyanate, 4゜4'-diphenylsulfide diisocyanate, 1,5-naphthalene diisocyanate, 2,6
- Aromatic diisocyanates such as naphthalene diisocyanate, toridine isocyanate, 4,4'-biphenyl diisocyanate, p-xylylene diisocyanate, m-xylylene diisocyanate; isophorone diisocyanate, 1,3-bis(isocyanatemethyl)cyclohexane, ■.

4-bis(isocyanatomethyl)cyclohexane, 4
, 4'-dicyclohexylmethane diisocyanate, 4
, 4'-dicyclohexyl ether diisocyanate; and aliphatic diisocyanates such as butane diisocyanate, hexamethylene diisocyanate, octamethylene diisocyanate, lysine diisocyanate, and trimethylhexamethylene diisocyanate.

These can be used alone or in combination.

The diisocyanate and tetracarboxylic acids are usually mixed in the organic solvent at a temperature of 50 to 250°C and a temperature of 0.5 to 2.
The reaction is carried out for 0 hours.

This organic solvent is not particularly limited, but the solid content concentration is usually 0.1 to 30% by weight, preferably 0.5 to 20% by weight.
The amount is such that

Furthermore, polyamideimide is synthesized from trimellitic acids and diamines. These trimellitic acids are
Examples include trimellitic anhydride and halides of trimellitic anhydride.

On the other hand, examples of the diamine for synthesizing polyamideimide include diamines that can be used for synthesizing the polyamide acid.

Furthermore, polyesterimides are synthesized from trimellitic acids, diamines and dihydroxy compounds. Here, the trimellitic acid and diamine may be the same as those used in the synthesis of the polyamideimide described above.

In addition, examples of dihydroxy compounds include hydroquinone, catechol, resorcinol, 2-methylresorcinol, bisphenol A, dichlorobisphenol A
1 Tetrachlorbisphenol A1 Bisphenol F1
Bisphenol S14.4'-Dihydrophenol ether, 1,5-dihydronaphthalene, 4-dihydronaphthalene, 2,2'-dihydroxybenzophenone, 4,4'-dihydroxybenzophenone, and the like.

These polyamideimides and polyesterimides are synthesized by heating in an organic solvent in the same manner as in the synthesis of polyamide acids or polyimides described above.

Intrinsic viscosity Cηrflh −An of the polyamide derivative and/or imide polymer (hereinafter simply referred to as “imide polymer”) used in the present invention as described above
('7rllt /C), c=0. 5g/d! ,3
0°C, in N,N-dimethylacetamide] is usually 0
．． 05-10dl/g, preferably 0.05-5dl/
It is g.

Next, polyhydric alcohol E'f'r used in the present invention
Examples of the tetramer include glycerin derivatives represented by general formula (1), diol derivatives represented by general formula (II), and the like.

CHz 0Rff (where Rl and R:l are the same or different and represent a hydrogen atom, an alkyl group having 5 to 30 carbon atoms, an alkenyl group having 5 to 30 carbon atoms, an aryl group having 6 to 18 carbon atoms, and (One of them is an alkyl group, an alkenyl group, or an aryl group.) R'-(OR") I, -OR'
...... (II) [In the formula, R4 and R5 are the same or different and are the same as R1 to R3 in the general formula (1), and R6 is a divalent alkylene group having 1 to 6 carbon atoms, n
represents an integer from 1 to 20. ] -OR of the glycerin derivative represented by this general formula (1)
', -OR' or -OR' includes, for example, pentanoyl, hexanoyl, heptanoyl, octanoyl,
Saturated aliphatic groups such as nonanoyl, decanoyl, undecenoyl, dodecanoyl, tridecanoyl, tetradecanoyl, pentadecanoyl, hexadecanoyl, heptadecanoyl, octadecanoyl, nonadecanoyl, eicosanoyl, heneicosanoyl, docosanoyl, tricosanoyl, tetracosanoyl; pentenoyl, hexenoyl, Mention may be made of unsaturated aliphatic groups such as heptenoyl, oftenoyl, nonenoyl, decenoyl, undecenoyl, docosanoyl, tridecenoyl, tetradecenoyl, pentadecenoyl, heptadecenoyl, octadecenoyl, nonadecenoyl, eicosanoyl, heneicosenoyl, decosenoyl, tricosanoyl, tetracosanoyl.

Specific examples of the glycerin derivative represented by the general formula (1) include glycerin monooctadecanoate, glycerin triotadecanoate, glycerin monooctadecenoate, glycerin triotadecenoate, and glycerin monopentanoic acid. Examples include glycerin tripentanoic acid ester, glycerin monodecanoic acid ester, glycerin tridecanoic acid ester, glycerin monohexadecanoic acid ester, glycerin trihexadecanoic acid ester, and the like.

Further, R4 and R5 of the diol derivative represented by the general formula (II) are the same as R1 to R3 represented by the general formula (1), and R6 is, for example, an ethylene group, 1.2 -propylene group, 1,3-propylene group,
1.4-butylene group, l.

■-2 with 1 to 6 carbon atoms such as dichloromethylethylene group
is a valent alkylene group.

Specific examples of the diol derivative represented by the general formula (II) include ethylene glycol-n-decyl ether,
Ethylene glycol-di-n-decyl ether, ethylene glycol-n-hexadecyl ether, ethylene glycol-di-n-hexadecyl ether, ethylene glycol-n-octadecyl ether, ethylene glycol-di-n-octadecyl ether, diethylene glycol- Examples include n-octadecyl ether, triethylene glycol-n-octadecyl ether, and propylene glycol-n-octadecyl ether.

The above glycerin derivatives and diol derivatives may be used alone or in combination of two or more.

Further, the amount of the polyhydric alcohol derivative added to 100 parts by weight of the imide polymer is usually 0.05 to 300 parts by weight, preferably 0.1 to 100 parts by weight, and 0.05 to 300 parts by weight.
If it is less than 300 parts by weight, the pretilt angle required for use as a liquid crystal alignment film cannot be obtained, while if it exceeds 300 parts by weight, the thermal stability of the liquid crystal alignment film made from the composition will decrease, and the liquid crystal alignment film may not be suitable for liquid crystal display elements. stable display characteristics may not be obtained.

Note that the amount of the polyhydric alcohol derivative added is arbitrarily selected within the above range depending on the pretilt angle, since the required pretilt angle changes depending on the structure of the liquid crystal display element used.

The composition of the present invention is usually prepared by dissolving the imide-based polymer and polyhydric alcohol derivative in an organic solvent and reducing the solid content. a
0.1-30% by weight, preferably 0.5-20% by weight
Prepare a solution of

At this time, the solution viscosity of a 5% by weight solution of the composition is usually 10 to 1 OO cps.

Examples of this organic solvent include the same organic solvents as those used in the production of the polyamic acids. In addition, the organic solvent in this case includes alcohols, ketones, esters, ethers, halogenated hydrocarbons, hydrocarbons such as methyl alcohol, ethyl alcohol, isopropyl alcohol, Cyclohexanol, ethylene glycol, propylene glycol, 1,4-butanediol, triethylene glycol, ethylene glycol monomethyl ether, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl acetate, ethyl acetate, butyl acetate,
Diethyl oxalate, diethyl malonate, diethyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n-propyl ether, ethylene glycol-j-propyl ether, ethylene glycol-n-methyl ether, ethylene glycol dimethyl ether, ethylene glycol ) Nocol ethyl ether acetate, diethylene glycol dimethyl ether, tetrahydrofuran, dichloromethane, 2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, 0-dichlorobunzene, hexane, heptane, octane, benzene, toluene, xylene, etc. can also be mixed to the extent that the imide polymer is not precipitated.

A liquid crystal display element using the composition of the present invention as a liquid crystal alignment film can be manufactured, for example, by the following method.

First, the composition solution is applied to a substrate having a transparent electrode by a roll coater method, a spinner method, a printing method, etc. to form a coating film. Dry at CCD temperature for 5-180 minutes, preferably 30-90 minutes.

The thickness of this coating film after drying is usually 0.01 to 1 μm,
Preferably it is 0.01 to 0.5 μm.

Note that in order to further improve the adhesion between the substrate and the liquid crystal alignment film, a silane coupling agent, a titanium coupling agent, or the like may be applied on the substrate in advance.

Specific examples of this silane coupling agent include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N-(
2-aminoethyl)-3-amino-propyltrimethoxysilane, N-(2-aminoethyl)-3-amino-propyltriethoxysilane, N-(2-aminoethyl)
-3-amino-propylmethyldimethoxysilane, 3-
Ureido-propyltrimethoxysilane, 3-ureido-propyltriethoxysilane, N-ethoxycarbonyl-3-amino-propyltrimethoxysilane, N-ethoxycarbonyl-3=aminopropyltriethoxysilane, N-1- Rimethoxysilylbrobyrutriethylenetriamine, N-)liethoxysilylpropyltriethylenetriamine, I(]-]trimethoxysilyl-14.7-)riazabucan, 9-trimethoxysilyl-3,6-diazatunyl acetate , 9-triethoxysilyl-3,6-diazatunyl acetate, N-benzyl-3-amino-propyltrimethoxysilane, N-benzyl-3-amino-propyltriethoxysilane, N
-phenol-3-amino-propyltrimethoxysilane, N-phenol-3-amino-propyltriethoxysilane, N-bis(oxyethylene)-3-amino-
Examples include propyltrimethoxysilane, N-bis(oxyethylene)-3-amino-propyltriethoxysilane, and the like.

Examples of the titanium coupling agent include isopropyl triisostearoyl titanate, isopropyl trilauryl titanate, isopropyl trimyristyl titanate, isopropyl dimethacryloyl isostearoyl titanate, isopropyl tri(dodecylhenzensulfonyl) titanate, and isopropyl isostearoyl diacryloyl titanate. , isopropyltri
(diisooctyl phosphate) titanate, isopropyl trimethacryloyl titanate, isopropyl tri (dioctyl pyrophosphate) titanate, isopropyl triacroyl titanate, isopropyl tri
Monoalkyl titanates such as (dioctyl phosphate) titanate, butyltriisostearoyl titanate, ethyl isostearoyl titanate; bis(triethanolamine) diisopropyl titanate, bis(triethanolamine) dibutyl titanate, bis(triethanolamine) diethyl titanate , bis(triethanolamine) dimethyl titanate, diisopropyl dilauryl titanate, diisopropyl lauryl myristyl titanate, diisopropyl distearoyl titanate, diisopropyl stearoyl methacryloyl titanate, diisopropyl diacryloyl titanate, diisopropyl didodecylbenzenesulfonyl titanate, diisopropyl isostearoyl-4-aminobenzoyl Mention may be made of di- or trialkyl titanates such as triisopropyl acryloyl titanate, triethyl methacryloyl titanate, triisopropyl myristyl titanate, tributyl dodecylbenzenesulfonyl titanate, triisopropyl stearoyl titanate, triisopropylisostearoyl titanate.

The silane coupling agent or titanium coupling agent can also be used by being mixed into a composition containing the imide polymer and the polyhydric alcohol derivative.

Substrates used in liquid crystal display devices include float glass, soda glass, flexible polyester films such as polyethylene terephthalate and polybutylene ethylene phthalate, and transparent films made of polyether sulfone, polycarbonate, and other plastic films. A substrate can be used, and as a transparent electrode, S
NESA film made of nO2, Inz 03 Sno
An ITO film made of W can be used, and these transparent electrodes can be patterned by a photo-etching method or a method using a mask in advance.

The coating film thus obtained is rubbed with a roll wrapped in a cloth made of synthetic fibers such as nylon, and subjected to liquid crystal alignment treatment.

Next, the periphery of the pair of substrates processed as described above is sealed with a sealant with a certain interval so that the rubbing directions are perpendicular or antiparallel, and liquid crystal is filled between the two substrates. A liquid crystal cell is formed by sealing the filling port with a sealant, and a liquid crystal display element is formed by pressing orthogonal or parallel polarizing plates to both sides of the cell.

As the sealant, for example, an epoxy resin containing a hardening agent and aluminum oxide spheres as a spacer can be used.

Further, the liquid crystal used in the liquid crystal display element is not particularly limited as long as it has positive dielectric anisotropy, but it is preferably one that forms a nematic type liquid crystal, such as symph-based liquid crystal, azoxy-based liquid crystal, or biphenyl-based liquid crystal. , phenylcyclohexane liquid crystal, ester liquid crystal, terphenyl liquid crystal, biphenylcyclohexane liquid crystal, pyrimidine liquid crystal, dioxane liquid crystal, bicyclooctane liquid crystal, and cupane liquid crystal.

These liquid crystals are usually used as a mixture, but may be used alone.

Furthermore, for these liquid crystals, cholestyl chloride,
Cholesteric liquid crystals such as cholesteryl nonaate and cholesteryl carbonate, and product names C-15 and CB-15
It is also possible to add and use chiral agents such as those sold as (manufactured by British Drug House).

Also, p-decyloxybenzylidene-p'-amino-2
- Ferroelectric liquid crystals such as methylbutyl cinnamate (DOBAMBC) can also be used.

Further, as the sealant, there are organic sealants and inorganic sealants, and organic sealants are particularly preferred because they can be operated at low temperatures.

The polarizing plate used on the outside of the liquid crystal cell is a polarizing plate in which a polarizing film called I] film, which is made by stretching and aligning polyvinyl alcohol and absorbing iodine, is sandwiched between cellulose acetate protective films, or a polarizing plate consisting of the 11 film itself. etc. can be mentioned.

A liquid crystal display element using the composition of the present invention as a liquid crystal alignment film can be used for any liquid crystal display such as an SBE display element, a TN type display element, or a ferroelectric liquid crystal display element by selecting the liquid crystal to be used. be able to.

For example, the pretilt angle between the liquid crystal alignment film and the liquid crystal using the above-mentioned composition containing an imide-based polymer and a polyhydric alcohol derivative is 3° or less in the conventional polyimide film, but in the present invention, the pretilt angle is 3° to 90°. It can be arbitrarily selected by changing the proportion of the polyhydric alcohol ML'4 in the composition, and is particularly excellent for SBE display elements.

〔Example〕

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

In addition, in the examples, the measurement of the pretilt angle is based on the literature CT,
J, 5cheffer, et, al,, J,Δ
pp1. Phys.

48, 1783 (1977), F. Nakano
, et, at,, JPN.

J, Appl, Phys, 19.2013 (
1,980)), laser light (He
-Ne) was measured by the crystal rotation method.

Example 1 (114,4'-diaminodiphenylmethane 19.84
g (0.1 mol) of N,N-dimethylacetamide (
DMAC) Dissolve in 380.2g, stirring 2
, 22.4 g (0.1 mol) of 3.5-1-licarboxycyclobentyl acetic dianhydride was added thereto, and the mixture was reacted at room temperature for 6 hours to obtain a polyamic acid solution.

Intrinsic viscosity of the obtained polyamic acid [η3, -ffn(η
rat /c), c=0. 5g/Li1.30℃,
in DMAC] was 1.83 dl/g.

(2) 25 g of glycerin monooctadecanoate is dissolved in 100 g of the polyamic acid in the polyamic acid solution obtained in (1) above, and DMAC is further added to solidify the polyamic acid and glycerin monooctadecanoate. A composition solution having a concentration of 5% by weight was prepared. The &li product natural solution thus obtained has a pore size of 0.
It was filtered through a 22 μm filter to remove insoluble matter.

This composition solution was applied to the transparent electrode surface of a glass substrate with a transparent electrode made of [TO] using a spinner at a rotation speed of 3.0.
The coating was applied for 3 minutes at 00 rpm.

Furthermore, it was dried at 180° C. for 3 hours to obtain a coating film with a thickness of 0.1 μm.

Next, this coating film was applied to a rubbing machine having a roll wrapped with nylon cloth at a rotation speed of 5.
The rubbing process was performed at 0 rpm and a stage movement speed of 1 cm/sec.

Next, an epoxy resin adhesive containing a spacer having a diameter of 17 μm was screen printed on the above-treated pair of substrates, and then the upper and lower substrates were pressed together so that the rubbing directions were antiparallel.

Next, a nematic liquid crystal containing a chiral agent (manufactured by Merck & Co., Ltd., ZLI-1565) was injected, and the injection port was sealed to produce a liquid crystal display element.

The orientation of this liquid crystal display element was good, and the pretilt angle was measured to be 3.8°.

Example 2 (1) DM was added to the polyamic acid solution obtained in Example 1 (fl).
422 g of AC was added, and further 14.2 g of pyridine and 18.4 g of acetic anhydride were added, and the mixture was reacted at 130° C. for 5 hours to obtain a polyimide.

The polyimide thus obtained was precipitated in methanol, washed with methanol, dried under reduced pressure, and then dissolved again in DMAC to prepare a 10% by weight polyimide solution.

The intrinsic viscosity of the polyimide thus obtained ("+n
h=An ('7rat/c), c=0. 5g
/d130°C in DMAC] was 0.98 dl/g. Further, when analyzed using nuclear magnetic resonance spectroscopy (NMR), it was found that this product had 90% polyimide units and 10% polyamic acid uniisomer.

(2) To 100 g of polyimide in the polyimide solution prepared in (1) above, 25 g of glycerin monooctadecanoate was dissolved, and DMAC was further added, so that the solid content concentration of polyimide and glycerin monooctadecanoate was 5 A composition solution with a pore size of 0.0% by weight was prepared.
It was filtered through a 22 μm filter.

Using this composition solution, a liquid crystal display element was produced in the same manner as in Example 1 (2), and the pretilt angle was measured to be 4.6'.

Example 3 (11) D was added to the polyamic acid solution obtained in (1) of Example 1.
422 g of MAC was added, and further 39.6 g of pyridine and 30.6 g of acetic anhydride were added, and the mixture was reacted at 130° C. for 5 hours to obtain a polyimide solution.

The polyimide thus obtained was precipitated in methanol, washed with methanol, dried under reduced pressure, and then dissolved again in DMAC to prepare a 10% by weight polyimide solution.

The intrinsic viscosity of the polyimide thus obtained [ηi,
, h = 1 n (ηr, L/c), c-0,5g/
a, 30°C, in DMAC] was 1.02 dl/g. Also, analysis using nuclear magnetic resonance spectroscopy (NMR) revealed that this was a polyimide consisting of more than 99% polyimide units. .

(2) 25 g of glycerin monooctadecanoate is dissolved in 100 g of polyimide in the polyimide solution obtained in (1) above, and DMA C is further added to adjust the solid concentration of polyimide and glycerin monooctadecanoate. A 5% by weight composition solution was prepared and the pore size was 0.
．． It was filtered through a 22 μm filter.

Using this composition solution, a liquid crystal display element was produced in the same manner as in Example 1 (2), and the pretilt angle was 1 (q was determined to be 4.8°).

Comparative Example 1 A liquid crystal display element was produced in the same manner as in (2) of Example 1, except that glycerin monooctadecanoic acid ester was not added when preparing the composition solution in (2) of Example 1. When the pretilt angle was measured, it was 0.64°.

Examples 4-10 Using the same method as Examples 1-2, polyamic acid and polyimide were synthesized in the proportions shown in Table 1, and the resulting imide polymer and the glycerin derivatives shown in Table 1 were synthesized. was dissolved in DMAC to prepare a composition solution with a solid content concentration of 5% by weight, and filtered through a filter with a pore size of 0.22 μm.

Using this composition solution, a liquid crystal display element was produced in the same manner as in Example 1 (2), and the pretilt angle was measured.

The results are shown in Table 1.

(Leaving space below) Table 1 *1) TCAAH-2,3,5-tricarboxycyclopentyl acetic dianhydride *2) DDM = 4.4'-diaminodiphenylmethane *3) DDE = 4.4'-diaminodiphenyl ether $ 4) BTDA-=3.3', 4.4'-Hensephenonetetracarboxylic dianhydride *5) PMDA-pyromellitic dianhydride**) Addition amount (g) per 100 g of imide polymer [Invention [Effect] A liquid crystal display element using the composition of the present invention as a liquid crystal alignment film can be obtained by applying a composition containing an imide polymer and a polyhydric alcohol derivative onto a substrate and/or a pattern of transparent electrodes, and then rubbing the composition. By making it into a liquid crystal alignment film,
This is a liquid crystal display element that has excellent contrast and visibility dependence and a large pretilt angle, and is particularly useful as an SBE display element.

Furthermore, a liquid crystal display element using the composition of the present invention as a liquid crystal alignment film has excellent alignment properties and reliability, and when combined with a polarizing plate such as a linear polarizing plate or a circular polarizing plate,
It can be effectively used in various devices, such as display devices such as desktop calculators, wristwatches, table clocks, coefficient displays, word processors, personal computers, and liquid crystal televisions.

Patent applicant: Japan Synthetic Rubber Co., Ltd. Agent: Patent attorney Takashi Shirai

Claims (1)

[Claims] (1) A composition for a liquid crystal alignment film containing a polyamide derivative and/or an imide polymer and a polyhydric alcohol derivative.