Method of making printed wiringboards

摘要

A predetermined portion of a wiring substrate having wiring patterns obtained by etching a copper layer formed on an insulating substrated is covered with a plating resistant first insulating film, then a portion of lead patterns is covered by a removable and plating resistance second film. Then overplated coating is applied onto predetermined wiring patterns and thereafter the second film is removed. Thereafter only lead patterns are selectively etched off.