TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Component: The blast material contains particles of carbon dioxide. The surface treating agent is silane coupling agent. The conductive layer contains copper.    TECHNOLOGY FOCUS - POLYMERS - Preferred Film: The cleaned surface portion of resin film is used to form an adhesive layer, and a conductive layer is formed on the adhesive layer. The conductive layer contains two or more metal layers, and formed by performing fusion process or chemical vapor deposition. The resin film is polyimide film obtained by polymerizing acidic component containing 3,3',4,4'-biphenyl tetracarboxylic acid and diamine component containing p-phenylenediamine. EXAMPLE - N,N-dimethyl acetamide, 3,3',4,4'-biphenyl tetracarboxylic-acid dianhydride and para-phenylenediamine were added, and polymerized at 30 degrees C, to polyimide precursor solution. Colloidal solution (0.1 mass parts) having average particle diameter of 0.08 mu m and monostearyl phosphate ester triethanolamine salt (0.5 mass parts) were added to 100 mass parts of precursor solution, and uniformly mixed, to obtain polyimide precursor solution composition. The polyimide precursor solution composition having rotation viscosity of 3000 poise was continuously extruded into smooth metal support component and dried, to form thin film on support component. Then, N.N-dimethylacetamide solution containing N-phenyl-( gamma )-aminopropyl trimethoxysilane as silane coupling agent was coated on the thin film, and dried at 80-120 degrees C, to form a polyimide film. The obtained polyimide film had average thickness of 35 mu m and linear expansion coefficient of 11-14 ppm/ degrees C. Silicon rubber roller was pressed against the silane coupling agent coated surface of polyimide film. Then, the surface-contacted with silicon rubber roller was cleaned using carbon-dioxide jet cleaner at 0.5 Mpa for 30 seconds. Then, copper layer is formed on the surface-cleaned polyimide film, to obtain copper plated laminated film. The copper plated laminated film has peeling strength of 0.8-0.9 N/mm at 23 degrees C and 14 N/mm at 90 degrees C based on JIS.C6471.