| 摘要 |
PURPOSE:To shorten and cleanse a circuit pattern forming process so as to improve a pattern in accuracy by a method wherein a ribbon or a sheet provided with a specified etching resist ink layer is provided onto a high molecular film support, and a pattern of the ink layer is thermally transferred onto a metal plated laminar board. CONSTITUTION:A high molecular film is made to serve as a support 5, a ribbon or a sheet 4 provided with a thermally transferring etching resist ink layer 6 of a resin base, which dissolves in or swells with an alkaline water solution and whose melting point is 40-150 deg.C, and a metal plated laminar board 1 are overlapped with each other making the ink layer 6 and a metal layer 3 face each other. A required circuit pattern formed of the ink layer 6 is thermally transferred onto the metal layer 3, and the exposed metal layer 3 is dissolved to be removed through an etching. A thermal transfer etching resist ink layer 7 left on the circuit pattern is treated with an alkaline water solution to remove. By these processes, a printed wiring board 12 provided with a metal layer 3' of a circuit pattern can be obtained, so that an etching resist film high in a pattern accuracy can be safely and rapidly formed at a low cost. |
