Abstract: The present invention relates to an aqueous alkali-developable photosensitive polyimide precursor resin composition that is appropriate for highly heat-resistant transparent protection layers and insulation layers for liquid crystal display devices.

Abstract: The present invention relates to an aqueous alkali-developable photosensitive polyimide precursor resin composition that is appropriate for highly heat-resistant transparent protection layers and insulation layers for liquid crystal display devices.

Abstract: The present invention relates to an aqueous alkali-developable photosensitive polyimide precursor resin composition that is appropriate for highly heat-resistant transparent protection layers and insulation layers for liquid crystal display devices. In more detail, the present invention relates to a negative-type photosensitive transparent polyimide precursor resin composition manufactured in two steps.

Abstract: The present invention relates to an aqueous alkali-developable photosensitive polyimide precursor resin composition that is appropriate for highly heat-resistant transparent protection layers and insulation layers for liquid crystal display devices. In more detail, the present invention relates to a negative-type photosensitive transparent polyimide precursor resin composition manufactured in two steps.

Abstract: The invention herein relates to a process of preparing a novel polyimide foam having superior heat-resistance, flame retardancy, homogeneous size and distribution of cells, and low density, wherein a polyimide precursor in a granular form is prepared by means of using heterocyclic amine as catalyst and then foaming. According to the present invention, the preparing process of a polyimide foam comprises reacting aromatic carboxylic acid or the anhydrides thereof with an excess of aliphatic univalent alcohol to yield an aromatic ester solution. To the aromatic ester solution, divalent amines or the mixture thereof were added in the equivalent amount of said carboxylic acid or the anhydrides thereof in addition to a catalyst and surfactant to yield a polyimide. Then, the precursor in a granular form mixture was imidized while foaming by means of pre-heating and then heating in a microwave oven, after which was cured at a high temperature.

Abstract: The invention herein relates to a soluble polyimide resin having a dialkyl substituent for a liquid alignment layer, wherein aliphatic tetracarboxylic dianhydride and aromatic diamine having a dialkyl substituent are used to yield said soluble polyimide resin which has superior heat-resistance, solubility, transparency, and liquid crystal alignment capacity. According to the present invention, the soluble polyimide polymer having a dialkyl substituent, for a liquid crystal alignment layer, comprising the following a repetitive unit of formula 1: ##STR1## Consequently, the polyimide resin under the present invention not only has superior heat-resistance but also excellent solubility and transparency, which could be applicable as a liquid crystal alignment layer for the TFT-LCD requiring a low temperature processing.

Abstract: The invention herein relates to a novel soluble polyimide resin comprising polyalicyclic structures and the process of preparation of the same, wherein aromatic tetracarboxylic dianhydride and novel aromatic diamine having an polyalicyclic group with various structures are used to yield a novel form of a polyimide resin, which has superior heat-resistance, solubility, and transparency.More specifically, the invention herein relates to a novel polyimide resin having excellent heat-resistance and solubility, which is prepared by means of reacting diamine monomers having a novel chemical structure with various types of aromatic carboxilic dianhydrides, in stead of aromatic diamine used for the preparation of the conventional polyimide resin. As a result, the polymers so obtained had the glass transition temperature of 260.degree. C..about.410.degree. C. and showed a increase in solubility in proportion to the increase in a number of the aromatic rings between two phenyl groups.

Abstract: The invention herein relates to a soluble polyimide resin for a liquid crystal alignment layer and the manufacturing method thereof, wherein a mixture of aliphatic tetracarboxylic acid dianhydrides and aromatic diamine having aliphatic side chains are used to yield a soluble polyimide resin which has superior heat-resistance, solubility, surface hardness, transparency and liquid crystal alignment capacity.The soluble polyimide resin having alkoxy substituents, for a liquid crystal layer, according to the present invention, is manufactured by adding a mixture of dioxotetrahydrofuran 3-methylcyclohexene-1,2-dicarboxylic dianhydride, which is an aliphatic tetracarboxylic acid dianhydride and aromatic tetracarboxylic acid dianhydride to a mixture of aromatic diamine, and said dioxotetrahydrofuran 3-methylcyclohexene- 1,2-dicarboxylic dianhydride is used in the amount of 50 to 99 mol % to the total amount of anhydrides.

Abstract: The invention herein relates to a soluble polyimide resin and the process of preparation of the same, wherein aromatic tetracarboxylic dianhydride and aromatic diamine having an alicyclic group with various structures of substituted alkyl groups are used to yield a novel form of a polyimide resin, which has superior heat-resistance, solubility and transparency.More specifically, the invention herein relates to a novel polyimide resin having excellent heat-resistance and solubility, which is prepared by means of reacting aromatic diamine monomers having a novel chemical structure with various types of aromatic tetracarboxilic acid dianhydrides, in stead of aromatic diamine used for the preparation of the conventional polyimide resin. As a result, the polymers so obtained had the glass transition temperature of 250.degree. C..about.400.degree. C. and showed a increase in solubility in proportion to the increase in volume of the alkyl group.

Abstract: The invention herein relates to a soluble polyimide resin for a liquid crystal alignment layer and the process of preparation of the same, wherein aliphatic tetracarboxylic dianhydride and aromatic diamine having the amide group are used to yield a novel form of a polyimide resin having superior heat-resistance, solubility, transparency, and liquid crystal alignment capacity.More specifically, the invention herein relates to a novel polyimide resin having excellent heat-resistance, solubility, liquid crystal alignment property, and high pretilt angle, which is prepared by means of jointly using the aromatic diamine, used for the preparation of the conventional polyimide resin, and the aromatic diamine having a long alkyl chain with a substituted amide group, and reacting the same with various types of carboxylic dianhydride.

Abstract: The disclosure describes a process for preparing a polyamideimide resin having high molecular weight in a simple manner wherein major problems of the prior processes such as low heat resistance and low melt flowability are improved. The process comprises condensation of an aromatic tricarboxylic acid anhydride and an aromatic diamine in a polar solvent, subjecting the resulting diimidedicarboxylic acid to acyl halogenating agent treatment to give an intermediate having good reactivity at low temperature, and then subjecting the latter to direct polymerization by using diamine as a nucleophilic agent to give a polyamideimide resin having high molecular weight. The polyamideimide resin prepared by the present invention can be used as major heat resistant structural material in advanced industries and as paint, sheet, adhesives, sliding material, fiber and film having heat resistance.

Abstract: A polyamideamic acid resin prepolymer represented by formula A having isophorone diamine as one of monomers, ##STR1## in which k, l, m and n are integer of 1 or more, respectively, and ##EQU1## --R-- is at least one group selected from the group consisting of ##STR2## --R'-- is a cis- and trans-conformational mixture of ##STR3## high heat resistant polyamideimide foam produced therefrom, and processes for producing them are disclosed.

Abstract: A process for preparing polyamideimide resins having high molecular weights as described wherein major problems of prior art processes such as low heat resistance and low melt flowability are improved. Polyamideimide resins having an intrinsic viscosity of 0.4 to 1.50 dl/g as measured on a solution of dimethylacetamide as a solvent at a concentration of 0.5 g/dl at 30.degree. C., are prepared by reacting an aromatic tricarboxylic acid anhydride with an aromatic diamine in N-methyl pyrrolidone solvent in the presence of a first catalyst selected from a group consisting of thionyl chloride, p-toluenesulphonly chloride, sulfuryl chloride, cyanuric chloride and phosphorus trichloride at a temperature of 50.degree. C. to 130.degree. C. over a period of 1 to 5 hours and further reacting the resultant reaction mixture in the presence of a second catalyst which is a compound of the formula (RO).sub.

Abstract: Polyamideimide resins having the formula (I) ##STR1## in which repeating units are bound in a head to tail or head to head manner,R is at least two divalent groups selected from the group consisting of ##STR2## (cis-, trans- conformational mixture) wherein one divalent group is ##STR3## group in a PAI molecule, produced by introducing isophorone diamine into the conventional aromatic polyamideimide resins.

Abstract: This invention relates to the aromatic polyamide resin of the following general formula(I) having pendant silyl groups characterized in that the said polyamide resin has excellent solubility for the films to be easily prepared by solvent casting as well as useful as coating materials, can be used at higher temperature than the reported polyamides because of the excellent heat stability, and also has excellent adhesive strength in the blend with glass fiber.

Abstract: Nadimide-terminated polyarylate prepolymers having the formula (I) ##STR1## wherein n is an integer not less than 1, and cured polyarylate resins produced by thermal curing the prepolymers, and processes for producing them are disclosed.The cured polyarylate resins according to the present invention have excellent chemical resistance and high-temperature resistance as well as good mechanical properties and processability.