Abstract: A treating agent for liquid crystal alignment, which comprises a polyimide precursor containing repeating units of the formula (1) and having a polymerization degree of from 0.05 to 5.0 dl/g as calculated as the reduced viscosity (in N-methylpyrrolidone at a temperature of 30.degree. C. at a concentration of 0.5 g/dl), and a solvent-soluble polyimide containing repeating units of the formula (2) and having a polymerization degree of from 0.05 to 5.0 dl/g as calculated as the reduced viscosity (in N-methylpyrrolidone at a temperature of 30.degree. C. at a concentration of 0.5 g/dl): ##STR1## wherein each of R.sup.1 and R.sup.3 is a tetravalent organic group constituting a tetracarboxylic acid or its derivative, R.sup.2 is a bivalent organic group constituting a diamine, R.sup.4 is a bivalent organic group constituting a diamine having no fluorine-containing alkyl group or no long chain alkyl group having at least 6 carbon atoms, and each of m and n is a positive integer.

Abstract: An alignment treating agent for a liquid crystal cell, which is composed mainly of a polyimide and/or a polyimide precursor made by a reaction for polymerization of a tetracarboxylic acid derivative component with a diamine component, wherein at least one part of the diamine component is a diamine component of the following formula (1): ##STR1## wherein n is an integer of from 1 to 12, and which gives a tilt angle of at most 2.degree. to nematic liquid crystal.

Abstract: A diaminobenzene derivative represented by formula (1), and a polyimide obtained by reacting a diamine containing at least 1 mol % of said diaminobenzene derivative, with a tetracarboxylic acid and its derivatives to obtain a polyimide precursor and ring-closing it, having a repeating unit represented by formula (2), and a liquid crystal alignment film containing said polyimide. ##STR1## P is a single bond or --O--, --COO--, or --CONH--, Q is a cyclic substituent selected from an aromatic ring, an aliphatic ring, a hetero ring and their substitution products, R.sup.1 is an aliphatic ring, and R.sup.2 is C.sub.1-22 straight chain alkyl group, A is a tetravalent organic group constituting a tetracarboxylic acid, B is a bivalent organic group constituting a diamine.

Abstract: A treating method for liquid crystal alignment, which comprises applying polarized ultraviolet or electron rays to a polymer thin film formed on a substrate, in a predetermined direction relative to the substrate surface, and using the substrate to align liquid crystal without rubbing treatment, wherein the polymer thin film is a polyimide resin containing a repeating unit of the formula (I): ##STR1## (wherein R.sup.1 is a tetravalent organic group having an alicyclic structure, and R.sup.2 is a bivalent organic group), which is obtained by dehydration ring-closure of a polyimide precursor having a reduced viscosity of from 0.05 to 3.0 dl/g (in N-methyl-2-pyrrolidone at temperature of 300.degree. C. at a concentration of 0.

Abstract: A treating agent for liquid crystal alignment useful for formation of a liquid crystal alignment film obtained by coating a film on a substrate equipped with transparent electrodes, baking the film, and subjecting the film surface to a rubbing treatment, wherein the treating agent for liquid crystal alignment contains a polyimide precursor containing a repeating unit of the formula (I) and a solvent-soluble polyimide resin containing a repeating unit of the formula (II), and at least 1 mol % of R.sub.4 of the solvent-soluble polyimide resin of the formula (II) being a bivalent organic group constituting a diamine which has a long-chain alkyl group or fluorine-containing alkyl group with a carbon number of at least 6, and the solvent-soluble polyimide resin of the formula (II) being from 1 to 80% by weight based on the total polymer weight: ##STR1## (wherein each of R.sub.1 and R.sub.2 is a tetravalent organic group which constitutes tetracarboxylic acid or its derivative, each of R.sub.2 and R.sub.

Abstract: A polyimide varnish which is a solution having a polyimide and/or a polyimide precursor dissolved in an organic solvent and which is useful for forming a polyimide coating film on a substrate by coating the solution on the substrate followed by heat treatment, wherein from 5 wt % to 60 wt % of the organic solvent is a polypropylene glycol derivative of the formula (I): ##STR1## wherein n is 1 or 2, and R is hydrogen, a C.sub.1-4 alkyl group, a C.sub.1-4 alkenyl group or a C.sub.1-4 alkanoyl group.

Abstract: A treating agent for liquid crystal alignment useful for formation of a liquid crystal alignment film obtained by coating a film on a substrate equipped with transparent electrodes, baking the film, and subjecting the film surface to a rubbing treatment, wherein the treating agent for liquid crystal alignment contains a polyimide precursor containing a repeating unit of the formula (I) and a solvent-soluble polyimide resin containing a repeating unit of the formula (II), and at least 1 mol % of R.sub.4 of the solvent-soluble polyimide resin of the formula (II) being a bivalent organic group constituting a diamine which has a long-chain alkyl group or fluorine-containing alkyl group with a carbon number of at least 6, and the solvent-soluble polyimide resin of the formula (II) being from 1 to 80% by weight based on the total polymer weight: ##STR1## (wherein each of R.sub.1 and R.sub.2 is a tetravalent organic group which constitutes tetracarboxylic acid or its derivative, each of R.sub.2 and R.sub.

Abstract: The present invention relates to a liquid crystal alignment treating agent which comprises a polyimide resin prepared from a diamine including an aromatic diamine having at least one linear alkyl group of at least 6 carbon atoms per benzene ring as the essential component and a tetracarboxylic acid and its derivative.The liquid crystal alignment treating agent obtained in accordance with the present invention comprises a polyimide resin having an alkyl group on a side chain, and accordingly provides a liquid crystal-aligned film containing liquid crystal molecules stably having an enhanced inclined alignment angle (tilt angle) to a substrate.

Abstract: The present invention relates to a novel fluorine-containing diaminobenzene derivative having a perfluoroalkyl group and to a novel fluorine-containing polyimide which is produced from the said diaminobenzene as a starting material and to a novel polyimide having both a fluorine-containing group and/or a siloxane chain in the side chain thereof, the polyimide being produced from the said fluorine-containing diaminobenzene and fluorine-containing polyimide and to a liquid crystal-aligning agent with an elevated tilt angle, which contains a polyimide having a fluorine-containing group and a siloxane chain.

Abstract: The present invention relates to a novel fluorine-containing diaminobenzene derivatives having a perfluoroalkyl group and to a novel fluorine-containing polyimide which is produced from the said diaminobenzene as a starting material and to a novel polyimide having both a fluorine-containing group and/or a siloxane chain in the side chain thereof, the polyimide being produced from the said fluorine-containing diaminobenzene and fluorine-containing polyimide and to a liquid crystal-aligning agent with an elevated tilt angle, which contains a polyimide having a fluorine-containing group and a siloxane chain.

Abstract: A ferroelectric liquid crystal element comprising a pair of substrates each having a transparent electrode and an orientation controlling film formed on the electrode, and ferroelectric liquid crystal sandwiched between the substrates in contact with the film, wherein said orientation controlling film is an organic polymer film treated by rubbing treatment and capable of giving nematic liquid crystal a pretilt angle of at least 10.degree. to the substrate surface.

Abstract: This invention is concerned with a composition to be used as an agent for aligning liquid crystals in a liquid crystal cell, wherein liquid crystal molecules are aligned with an increased pretilt angle with respect to the substrate, such composition consists essentially of a polyimide resin precursor having repeating units represented by the formula (I) ##STR1## wherein R.sub.1 denotes an organic group constituting a tetracarboxylic acid or its derivative; and R.sub.2 represents a divalent organic group constituting a diamine; anda precursor of a diimide compound represented by the formula (II) or (III): ##STR2## wherein R.sub.3 denotes a divalent organic group constituting a diamine; each of R.sub.4 and R.sub.5 represents an organic groups constituting a dicarboxylic acid containing an alkyl group having 6 to 20 carbon atoms, or its derivative, ##STR3## wherein R.sub.6 denotes an organic group constituting a tetracarboxylic acid or its derivative, and each of R.sub.7 and R.sub.

Abstract: A liquid crystal aligning agent consisting essentially of a polyimide resin obtained by the polymerization of a diamine, a tetracarboxylic acid dianhydride and a monoamine of the formula:R.sup.2 (R.sup.1).sub.n NH.sub.2 (I)wherein R.sup.1 is a divalent organic group, R.sup.2 is an alkyl group having from 6 to 20 carbon atoms, and n is 0 or 1.

Abstract: A liquid crystal aligning agent consisting essentially of a polyimide resin obtained by the polymerization of a diamine, a tetracarboxylic acid dianhydride and a monoamine of the formula:R.sup.2 (R.sup.1).sub.n NH.sub.2 (I)wherein R.sup.1 is a divalent organic group, R.sup.2 is an alkyl group having from 6 to 20 carbon atoms, and n is 0 or 1.