| 摘要 |
PURPOSE: To produce an FPC in which variation in the physical properties due to absorption of moisture is suppressed without requiring adhesive by forming a copper layer directly at least on one side of a thermoplastic polyimide film. CONSTITUTION: A copper layer is formed directly at least on one side of a thermoplastic polyimide film shown by a formula. In the formula, R1 , R2 represents a bivalent organic group, R3 represents a tetravalent organic group, and m, n are positive integers. The thermoplastic polyimide film is produced by subjecting a precursor, i.e., a polyamide acid copolymer solution, to thermal and/or chemical dehydrating ring formation. The ultrathin copper foil with support is produced by forming a copper layer through deposition or plating on one side of the thermoplastic polyimide film. The polyamide acid copolymer is produced through copolymerization of aromatic dianhydride tetracarboxylic acid and a polyamide acid solution produced through reaction of aromatic dianhydride diester acid. |
