Apparatus for forming film hole
An exemplary film hole forming apparatus ( 400 ) includes a chemical etching system ( 410 ) and a driving system ( 420 ). The driving system includes a transmission belt, which passes through the chemical etching system. A material of the transmission belt is polytetrafluoroethylene, polytetrafluoroethylene-containing material, polyvinylidene fluoride, metal, or metal-sandwiched composite. An exemplary method for forming film holes includes the following steps: providing a flexible printed circuit board ( 300 ) to be etched, with copper holes ( 321 ) pre-formed thereat and the copper holes exposing a base film ( 310 ) at corresponding positions; and transporting the flexible printed circuit board into a chemical etching system by a transmission belt to form film holes in the base film.
1. A film hole forming apparatus for forming holes in a printed circuit board, the printed circuit board comprising a base film, two nichrome alloy layers formed on two opposite surfaces of the base film, and two copper films formed on the nichrome alloy layers, respectively, the copper films having copper holes formed therein, the nichrome alloy layers having nichrome holes formed therein, the nichrome holes being respectively in communication with the copper holes to expose portions of the base film, the film hole forming apparatus comprising:
a chemical etching system comprising an activating bath, a chemical etching bath, a water-washing bath, a slight-etching bath, and an end-washing bath in that sequence, the activating bath being configured for cleaning the printed circuit board, the chemical etching bath being configured for etching portions of the base film exposed at the nichrome holes and the copper holes, the water-washing bath being configured for washing the printed circuit board, the slight-etching bath being configured for removing portions of the nichrome alloy layers corresponding to the exposed portions of the base film, and the end-washing baths being configured for washing the printed circuit board; and
a driving system comprising a transmission belt passing through the activating bath, the chemical etching bath, the water-washing bath, the slight-etching bath, and the end-washing bath, the transmission belt being configured for carrying the printed circuit board, a material of the transmission belt being polytetrafluoroethylene-containing material.
2. The film hole forming apparatus as claimed in claim 1 , wherein the polytetrafluoroethylene-containing material is a mixture of polytetrafluoroethylene and glass fiber.
3. The film hole forming apparatus as claimed in claim 1 , wherein the polytetrafluoroethylene-containing material is a mixture of polytetrafluoroethylene and polymer.
4. The film hole forming apparatus as claimed in claim 1 , wherein the chemical etching system further comprises a pre-washing bath after the chemical etching bath and an acid-washing bath between the pre-washing bath and the water-washing bath, the pre-washing bath being configured for washing the printed circuit board coming from the chemical etching bath, and the acid-washing bath being configured for neutralizing a chemical etching solution of the chemical etching bath remaining on the printed circuit board.