Patents by Inventor Richard Earl Ellwanger

Richard Earl Ellwanger 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).

  • Inversion of water-in-oil emulsions of polyacrylamide in hard water
    Patent number: 4115340
    Abstract: Anionic water-in-oil emulsions of polyacrylamide are readily inverted in hard water for dissolution of the polymer therein by effecting inversion at a dilution such that insufficient hardness is present to cause emulsion breaking.
    Type: Grant
    Filed: May 11, 1977
    Date of Patent: September 19, 1978
    Assignee: American Cyanamid Company
    Inventor: Richard Earl Ellwanger