| 摘要 |
PROBLEM TO BE SOLVED: To make feasible of the enhancement of elastic modules, the reduction of water absorption coefficient and the maintenance of a specific thermal expansion coefficient, by using a polyimide film made of poylimide copolymer produced by dehydrate ring closure polyamide copolymer having a specific structure as a base film. SOLUTION: An adhesive layer and a protective film are provided on a polyimide film produced by dehydrate ring closure a polyamide copolymer represented by a formula used as a base film. Within the formula, R1 represents bivalent organic radical selected from dephenylene, naphthalene, phenylene to be substituted with CH3 , Cl, Br, F, CH3 , O; R2 represents bivalent organic radical more than one kind; R3 represents quadrivalent organic radical more than one kind. The polyimide film is proeuded by dehydrate ring closure a polyamedic copolymer as a precursor of the polyimide film while this polyamidic copolymer can be produced by using substantially the same mol of acid anhydride and diamine component to be polymerized in an organic polarity solvent. |
