PURPOSE: To obtain a printed wiring board being excellent in a wiring density and a method for manufacturing this printed wiring board simply.
CONSTITUTION: (1) On the surface of an insulative bonding layer 7 or of the insulative bonding layer 7 laid on an internal-layer circuit sheet 8, a metal leaf 6 composed of three layers of a copper layer 6-3 to be a circuit, an intermediate layer 6-2 of nickel and a copper layer 6-1 to be a carrier is laid so that the copper layer 6-3 to be the circuit comes into contact with the insulative bonding layer 7. They are laminated to be integral by applying heat and pressure thereto and a hole is opened at a prescribed position. Subsequently, electroless plating 9 and also electroplating 9, when necessary, are conducted, the copper layer 6-1 to be the carrier is etched selectively and the intermediate layer 6-2 of nickel being exposed is removed by etching. (2) A conductor layer 6-3 to be the circuit is formed by selective etching, subjected to solder printing and melted and solidified.
SETOGUCHI SHINICHI
URASAKI NAOYUKI
NAKAZATO YUICHI
SUGANUMA MITSUTERU
IWASAKI YORIO
