Method null of hole opening the standard hole of negative film for printed circuit board production

摘要

PURPOSE: To provide a punching method wherein two holes are prevented from being different in a diameter from each other when the reference holes of two negative films for manufacturing a printed wiring board are simultaneously punched. ;CONSTITUTION: Two negative films 3 and 4 for manufacturing a printed wiring board and a soft sheet 5 are superposed together in a state that the soft sheet is arranged at the outside. The soft film 5 is placed on a punching device in such a way that the soft sheet 5 is arranged on the dice hole 7 side and a punch is pushed in the dice hole 7 to punch a hole.;COPYRIGHT: (C)1993,JPO&Japio