| 摘要 |
A copper foil for printed circuits has a roughened layer formed on the side of the foil to be bonded to a base, the roughened layer consisting of a number of protuberant copper electrodeposits containing chromium tungsten or both. It may also have a copper plating layer covering the roughened layer and a treatment layer covering the copper plating layer and formed of either a metal selected from the group consisting of copper, chromium, nickel, iron, cobalt, and zinc, or an alloy of two or more such metals. When necessary, the copper foil may contain an anticorrosive layer including various chromate treated layers further formed on the treatment layer. The copper foil is produced by electrolyzing a raw foil as a cathode in an acidic copper electrolytic bath at a current density close to the critical density, thereby forming the roughened layer, the electrolytic bath containing 0.001-5 g/l of chromium ion tungsten ion or both. The roughened layer is electrolytically overcoated with the treatment layer following the formation of a copper plating layer, which, when necessary, is anti-corrosively treated. |
