Alignment treating agent for liquid crystal cell
AssigneeNissan Chemical Industries, Ltd.
InventorsKiyoshi Sawahata, Toyohiko Abe, Yoshihiro Tsuruoka, Hiroyoshi Fukuro
Life of this patent
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Abstract
An alignment treating agent for a liquid crystal cell, which comprises a polyimide resin of the formula (I): wherein R1 is a tetravalent organic group constituting a tetracarboxylic acid or its derivative, R2 is a bivalent organic group constituting a diamine, and m is a positive integer, provided that at least 10 mol % of R2 is a bivalent organic group selected from the group consisting of: wherein X is H, OH, an alkyl group, an alkoxy group, a carboxyl group, an acyl group or a halogen atom, said polyimide resin being made insoluble in an organic solvent by coating a precursor solution of said polyimide resin on a substrate, followed by heating.
Claims10
An alignment treating agent for a super-twisted nematic liquid crystal cell, which comprises a polyimide resin of the formula (I):
- wherein R1 is a tetravalent organic group constituting a tetracarboxylic acid selected from the group consisting of pyromellitic acid, benzophenone tetracarboxylic acid, biphenyl tetracarboxylic acid, cyclobutane tetracarboxylic acid, cyclopentane tetracarboxylic acid, cyclohexane tetracarboxylic acid and butane tetracarboxylic acid, and dianhydrides and diacid halides thereof;
- and
- R2 is a bivalent organic group constituting a diamine, and m is a positive integer, provided that at least 10 mol % of R2 is a bivalent organic group selected from the group consisting of:
- and wherein X is H, OH, CH3, CH3O, COOH or Cl, said polyimide resin being made insoluble in an inorganic solvent by coating a precursor solution of said polyimide resin on a substrate, followed by heating at 170 to 350° C.
A process for producing an alignment treating agent for a super-twisted nematic liquid crystal cell, which comprises coating a precursor solution of a polyimide resin of the formula (I):
- wherein R1 is a tetravalent organic group constituting a tetracarboxylic acid selected from the group consisting of pyromellitic acid, benzophenone tetracarboxylic acid, biphenyl tetracarboxylic acid, cyclobutane tetracarboxylic acid, cyclopentane tetracarboxylic acid, cyclohexane tetracarboxylic acid and butane tetracarboxylic acid, and dianhydrides and diacid halides thereof, and
- R2 is a bivalent organic group constituting a diamine, and m is a positive integer, provided with at least 10 mol % of R2 is a bivalent organic group selected from the group consisting of:
- and wherein X is H, OH, CH3, CH3O, COOH or Cl, on a transparent substrate, heating the precursor solution to form a polyimide resin film, and applying a rubbing treatment to the resin film.
Dependencies are inferred from the claim text.