Patents Assigned to Elget Ing.-Bu/ ro fu/ r Grafische und Elektronische Technik
  • Metal stripping process and composition
    Patent number: 4424097
    Abstract: A stripper, for the removal of tin and tin compounds, in particular copper metal-resists in contact switches, comprises an aqueous solution of 5 to 20% v/v hydrochloric acid, 2.5 to 6.0 g/l copper and 9 to 40 g/l tin, as well as, at the beginning of the stripping process, up to 0.5 ml/l hydrogen peroxide or up to 0.015 ml/l of a surfactant.
    Type: Grant
    Filed: August 9, 1982
    Date of Patent: January 3, 1984
    Assignee: Elget Ing.-Bu/ ro fu/ r Grafische und Elektronische Technik
    Inventors: Erich Lipka, Eberhard Lendle