1. It is mentioned that ordinary electrolytic copper foil is a product made by galvan foil or copper plating. The peeling strength is not enough. When the bad foil suppression plate is made into a PCB plug -in in the electronics factory, the copper wire will fall off by the impact of external forces. This type of copper -throwing a copper thread to see the copper foil surface (that is, the contact surface of the substrate).

　　2. Poor adaptability of copper foil and resin: some special performance layer -made plates used now, such as HTG plates, because the resin system is different, the solid agent is generally PN resin, the resin molecular chain structure is simple, when the solidification is solidified, and when it is solidified The degree of cross -linking is low, and the copper foil with special peak values is necessary to match it. When the production layer is used, the copper foil is not matched with the resin system, resulting in insufficient peeling strength of the plate covering metal foil, and the copper thread will fall off during the plug -in.