Copper foil for printed circuit board with taking environmental conservation into consideration

摘要

A copper foil for a printed circuit board has a rust preventing layer formed by a trivalent chromium chemical conversion treatment on a surface of the copper foil that the copper foil is bonded to a base material for the printed circuit board. T copper foil is of copper or copper alloy, and the rust preventing layer contains 0.5 to 2.5 μg/cm² of chromium converted into metallic chromium.