METHOD FOR PRODUCING POLYIMIDE FILM ROLL

摘要

PROBLEM TO BE SOLVED: To provide a polyimide film keeping heat resistance and flexibility at a high level and causing no warpage due to heat. SOLUTION: A polyimide roll film is obtained by performing casting of an organic solvent solution containing polyimide precursor substance onto a support to form a film, thermally drying the film so that the difference between imidization ratio of the precursor film on one surface side and imidization ratio on the other surface side is≤5 and heat treatment of the resultant precursor film. A polyimide film roll is obtained by rolling up the resultant film with the A-surface side inside with a rolling tension of≥100 N so as to attain a radius of curvature ranging from 30 to 600 mm. The obtained polyimide film exhibits a curling degree after heating at 300°C of≤10% and a coefficient of variation of film linear expansion coefficient (CV%) of≤25%. COPYRIGHT: (C)2007,JPO&INPIT