Patents by Inventor Walter Johannes Rens

Walter Johannes Rens 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 producing polymeric film
    Patent number: 3944644
    Abstract: Polymeric film is stretched by pulling the film over a first roller which is heated and over a second roller which is cooled, the second roller rotating at a greater peripheral speed than the first roller. The necking-in of the film in the gap between the two rollers is considerably reduced if a heat-transfer liquid is applied betwen marginal portions only of the film and the corresponding peripheral portions of the second, cooled, roller.
    Type: Grant
    Filed: January 9, 1974
    Date of Patent: March 16, 1976
    Assignee: AGFA-Gevaert
    Inventors: Jan Baptist Van Cappellen, Walter Johannes Rens