Patents by Inventor Clark S. Thomas

Clark S. Thomas 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).

  • Metal etching composition
    Patent number: 5034093
    Abstract: The present invention is directed to a chemical etching composition for etching metals or metallic alloys. The composition includes a solution of hydrochloric acid, phosphoric acid, ethylene glycol and an oxidizing agent. The etching composition is particularly useful for etching metal surfaces in preparation for subsequent fluorescent penetrant inspection.
    Type: Grant
    Filed: September 25, 1990
    Date of Patent: July 23, 1991
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Joseph E. O'Tousa, Clark S. Thomas, Robert E. Foster