Patents by Inventor Hisao Sato

Hisao Sato 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).

  • Speaker edge
    Patent number: 3980841
    Abstract: An acoustic material suitable for use as a speaker edge comprises an expanded plastic and minute collagen fibers wherein the content of the collagen fibers is 15 - 40% based on the weight of the expanded plastic and the length of the fibers is equal to or less than 1 mm.
    Type: Grant
    Filed: May 23, 1975
    Date of Patent: September 14, 1976
    Assignees: K.K. Fujita Shoten, Hisao Sato
    Inventors: Hiroshi Okamura, Hisao Sato, Isamu Iwasaki