Patents by Inventor Frits W. Janssen

Frits W. Janssen 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).

  • Plasticity index improvers and method of use
    Patent number: 4020026
    Abstract: This invention provides a method of treating rubber in the latex or nonlatex form with polyethylenimine to improve the plasticity and plasticity retention index of the unvulcanized elastomer.
    Type: Grant
    Filed: April 17, 1975
    Date of Patent: April 26, 1977
    Assignee: The Goodyear Tire & Rubber Company
    Inventors: Frits W. Janssen, Edward A. Sinclair