Patent ID: 7659360

Claim:
A process for producing a polyimide resin, comprising a step of reacting at least one acyl-containing compound with at least one imino-forming compound, wherein the at least one acyl-containing compound consists essentially of one or more acyl-containing compounds selected from the group consisting of 1,2,4,5-cyclohexanetetracarboxylic acid represented by the following formula 1: 1,2,4,5-cyclohexanetetracarboxylic dianhydride represented by the following formula 2: reactive derivatives thereof, and the imino-forming compound is selected from the group consisting of compounds containing at least one phenylene group and at least one isopropylidene group, which is represented by the following formula 3: wherein X is —NH 2 , n is 2, and p is 0, wherein the reaction is conducted in an organic polar solvent in the presence of an imidation catalyst under heating, to produce a polyimide resin solution of said polyimide resin in said organic polar solvent from said acyl-containing compound and said imino-forming compound in a single step, the imidation catalyst being a tertiary amine, and wherein the heating is conducted at 160 to 200° C.