PURPOSE: To attain high working accuracy for polyimide resin by preventing the dissolution of polyimide resin at the time of forming a wiring board or the like by the use of a substrate made by forming a metallic coating film on the polyimide resin surface by electroless plating method.
CONSTITUTION: At the time of forming a resist layer composed of an organic material on the polyimide resin surface, the resist layer is provided on the polyimide resin surface which is brought into contact with a treating solution containing acetic anhydride and pryidine. As a result, the adhesive strength of polyimide resin to the resist is easily improved, the working accuracy of polyimide resin is increased and TAB tape or the like having high reliability is obtained.
ISHII CHIGUSA
HOSHINO ETSUKO
