Symptoms: Poor adhesion of printing materials, poor adhesion of coatings, inability to etch off certain parts, and inability to solder certain parts.

　　Possible inspection methods: Visual inspection is usually performed by forming visible water marks on the surface of the board:

　　Possible reason: Due to the extremely dense and smooth surface caused by the demolding film, the uncoated copper surface becomes excessively bright. Usually, on the uncoated side of the laminate, the laminate manufacturer does not remove the release agent. The pinholes on the copper foil cause resin to flow out and accumulate on the surface of the copper foil, which usually occurs on copper foils thinner than 3/4 ounce weight specifications. Copper foil manufacturers apply excess antioxidants to the surface of copper foil. The manufacturer of the laminated board has changed the resin system, demoulding thin, or brushing method.

　　Due to improper operation, there are many fingerprints or oil stains. Stain engine oil during punching, cutting, or drilling operations.

　　Possible solution: It is recommended that laminated panel manufacturers use fabric like films or other demolding materials. Contact the manufacturer of the laminated board and use mechanical or chemical elimination methods. Contact the laminated board manufacturer to inspect each batch of copper foil that fails the inspection; Request a solution to remove the recommended resin. Request a method of removal from the laminated panel manufacturer. Chang Tong recommends using hydrochloric acid, followed by mechanical grinding and brushing to remove it. Before any changes are made to the manufacturing of laminated panels, cooperate with the laminated panel manufacturer and specify the user's testing items.