| 摘要 |
PURPOSE:To produce a rough-surface polyimide film excellent in strengths, heat resistance, durability and running performance. CONSTITUTION:A process for producing a rough-surfaced polyimide film containing 10<4>-10<8> fine protrusions with diameters of 0.01-2mum per mm<2> of the surface, comprising casting a polyamic acid obtained from an aromatic tetracarboxylic acid comprising 15-85mol%, based on the whole tetracarboxylic acid component, biphenyltetracarboxylic acid and 85-15mol% pyromellitic acid and an aromatic diamine comprising 30-100mol%, based on the whole aromatic diamine component, phenylenediamine and 70-0mol% diaminodiphenyl ether over a support, heating the cast polyamic acid to obtain a self-supporting film, peeling this film from the support, and heating it under the conditions in which the maximum heating temperature is higher than the glass transition temperature of the aromatic polyimide film to be obtained. |
