Patents by Inventor Richard Redfearn Hepner

Richard Redfearn Hepner 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).

  • Process for depolymerizing polyester
    Patent number: 5912275
    Abstract: Polyester is depolymerized by methanolysis and methanol is recovered in a process that uses methyl benzoate and/or p-methyltoluate as an azeotropic agent while the methanol is present.
    Type: Grant
    Filed: September 30, 1997
    Date of Patent: June 15, 1999
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Stephen Dana Hall, Richard Redfearn Hepner, Robert Everett Michel, Donald Richard Wheatcraft, Jr., George Malcolm Williamson