| 摘要 |
PURPOSE:To perform the working of high positional accuracy by protecting with the support plate made by the 200-500 weight part of an inorg. powder and 100 weight part of a binder consisting of a polyolefine, in the case of piercing and cutting such a work made of a solid synthetic resin as a printed circuit board. CONSTITUTION:In the case of piercing and cutting a printed circuit board 1 consisting of a glass fiber reinforcing epoxy resin, etc., auxiliary plates 2, 3 are worked by superposing on the upper face or the upper and lower both faces in order to protect the work. The composition of this auxiliary plate is composed of 200-500 weight parts of an inorg. powder (e.g., an aluminum hydroxide, etc.) and 100 weight parts of a binder consisting of a polyolefine (e.g., low, medium and high density polyethylene, etc.). Now, the polyolefine increases the affinity and dispersibility with the inorg. powder, is excellent in cushioning property also and no harmful gas is generated at working time. The aluminum hydroxide also shows an endothermic action in case of piercing by a high speed rotary drill or cutting by a circular saw and the wear of a tool and operability are improved. |
