Patents by Inventor George J. P. Dujardin

George J. P. Dujardin 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).

  • Optically readable information disc
    Patent number: 4668549
    Abstract: Optically readable information disc having a substrate plate manufactured by an injection moulding process or a compression moulding process and composed of a mixture of 40-90% by weight of polymethylmethacrylate and 10-60% by weight of polyvinylchloride or chlorinated polyvinylchloride.
    Type: Grant
    Filed: February 3, 1986
    Date of Patent: May 26, 1987
    Assignee: U.S. Philips Corporation
    Inventors: Gerardus J. M. Lippits, Petrus E. J. Legierse, George J. P. Dujardin