Patents by Inventor Edwin R. Tefft

Edwin R. Tefft 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).

  • Synergistic antimicrobial composition of 1,2-dibromo-2,4-dicyanobutane and esters of parahydroxybenzoic acid
    Patent number: 5641808
    Abstract: Synergistic antimicrobial combinations comprising 1,2-dibromo-2,4-dicyanobutane and at least one ester of parahydroxybenzoic acid are disclosed. Methods for using these synergistic combinations to inhibit microbial growth are also disclosed.
    Type: Grant
    Filed: September 1, 1995
    Date of Patent: June 24, 1997
    Assignee: Calgon Corporation
    Inventors: Tammy W. Gaffney, Edwin R. Tefft
  • DMDAAC/AM copolymers as deinkers
    Patent number: 4786364
    Abstract: The instant invention is directed to a method for deinking cellulosic fibrous material impregnated with ink wherein a mixture of said material and water is stirred in the presence of a deinking agent, the improvement wherein the deinking agent is a hydrolyzed copolymer of dimethyldiallyl ammonium chloride and acrylamide.
    Type: Grant
    Filed: August 2, 1984
    Date of Patent: November 22, 1988
    Assignee: Calgon Corporation
    Inventor: Edwin R. Tefft