| 摘要 |
PURPOSE:To prevent exposure of a metal cored printed circuit board from an end of a metal plate by etching a cut end of the circuit board after the shape is machined. CONSTITUTION:A metal 1, an inner layer circuit board 2 having an electric circuit 2a (inner layer circuit pattern) formed of a copper foil and an outer layer copper foil 3 are laminated through a prepreg 4 to manufacture a metal cored printed circuit board. Then, a masking tape is stuck to an entire outer layer circuit layer by thermal press-bonding, and spray-etched from above and below with alkaline etchant. In this case, electric wirings of the outer layer is protected by the tape, but an end face of the metal plate exposed from a section of the circuit board is formed with a recess 6 by etching, and from the end of the metal plate the cut end of the circuit board is not exposed. After it is washed and temporarily dried, the tape is peeled, and dried. Eventually, the cut end of the circuit board is covered with synthetic resin 7. |
