DOUBLE LAYER FLEXIBLE BOARD AND METHOD FOR MANUFACTURING THE SAME

摘要

[PROBLEMS] To provide a double layer flexible board, which does not have defects on a copper film part due to a pin hole generated at the time of forming a base metal layer on an insulating film by dry plating process, has excellent adhesion between the insulating film and the base metal layer and corrosion resistance, and has a copper film layer having high insulation reliability, and to provide a method for manufacturing such double layer flexible board. [MEANS FOR SOLVING PROBLEMS] A double layer flexible board is provided by forming a base metal layer directly at least on one plane of an insulating film without having an adhesive in between, and then by forming a copper film layer on the base metal layer. The base metal layer having a film thickness of 3-50nm is formed by dry plating method and mainly contains a nickel-chrome-molybdenum alloy wherein the chrome ratio is 4-22wt%, the molybdenum ratio is 5-40wt%, and the rest is nickel.