Patents by Inventor Ellen L. Johnson

Ellen L. Johnson 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).

  • Method for preventing corrosion in aqueous systems
    Patent number: 4744949
    Abstract: A method for inhibiting corrosion in industrial cooling waters which contain hardness and a pH of at least 6.5, comprising using a water-soluble inorganic phosphate capable of inhibiting corrosion in an aqueous alkaline environment and a co- or terpolymer of acrylic acid and certain substituted acrylamides such as t-butyl acrylamide. A water-soluble organic phosphonate capable of inhibiting corrosion in an alkaline environment may be used as an adjunct for the phosphate.
    Type: Grant
    Filed: July 6, 1987
    Date of Patent: May 17, 1988
    Assignee: Nalco Chemical Company
    Inventors: John E. Hoots, Guy A. Crucil, Ellen L. Johnson