Kupferfolie für Leiterplatten und Verfahren zu ihrer Herstellung

摘要

A copper foil for printed circuits includes a thermal oxidation-resistant treated layer (e.g. Zn-Ni or Zn-Co alloy plating) formed on the shiny side of the foil and a Cr-base anticorrosive treated layer (e.g. chromate film, mixed film of chromium oxide and zinc and/or zinc oxide, or both) formed further thereon. A copper plated layer or an etched surface is provided on the shiny side before forming the thermal oxidation resistant treated layer. The copper plating or etching permits the shiny side to be completely covered with fresh copper or purified to overcome non-uniformity of chemical activity and/or any lack of smoothness of the entire surface of the shiny side. The evenness of the freshly formed copper surface enhances the homogeneity and completeness of the thermal oxidation-resistant plated layer to be formed subsequently by thermal oxidation resistance treatment, to maximise the advantages of this treatment. The treatment technique imparts to the shiny side of copper foil a thermal oxidation resistance to heating at 300 DEG C for 30 minutes.