Patents by Inventor Walter W. Baldauf, Jr.

Walter W. Baldauf, Jr. has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Regeneration of copper etch bath
    Patent number: 4880495
    Abstract: This invention relates to a copper etching process which involves contacting the copper with an aqueous etching solution comprising sulfuric acid and a peroxide to which is added less than about 0.2% of an organic additive useful as a crystallization control agent and selected from the group consisting of a low molecular weight glycol and gum arabic. With this compound present, copper sulfate crystals do not adhere to the tank and removal of the crystals from the bath is facilitated.
    Type: Grant
    Filed: April 13, 1987
    Date of Patent: November 14, 1989
    Assignee: The Harshaw Chemical Company
    Inventors: Kestutis F. Petraitis, Walter W. Baldauf, Jr.