| 摘要 |
PURPOSE:To augment the circuit bonding strength by a method wherein inner layer material with specified number of electric circuits is lamination-formed into one body and after printing electric circuits with a conductive material on the outermost surface of the laminated layer, the circuit parts are electroplated. CONSTITUTION:Respective upper surfaces and lower surfaces of inner layer material with specified number of electric circuits are lamination-formed into one body through the intermediary of resin layers. At this time, the practical thickness of the resin layers of 0.05-0.5mm is recommended. Next, after printing the electric circuit with a conductive material on the outermost surface of the laminated layer sheet, the circuit parts are electroplated. Such a printed wiring sheet can eliminate any etching process to augment the bonding strength of the electric circuits, thereby enabling the humidity resistance to be maintained further because such a material as Pd is not employed. |
