Patents by Inventor Keitaro Fukushima

Keitaro Fukushima 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 carbon fibers
    Patent number: 4113847
    Abstract: Carbon fibers are prepared by spinning a copolymer of a carboxyl group-containing unsaturated monomer and at least 85 mol% acrylonitrile, washing the filaments with water, stretching the filaments in hot acid water having a pH below 3.5, and heating the resultant fibers to cause carbonization or graphitization.
    Type: Grant
    Filed: September 1, 1976
    Date of Patent: September 12, 1978
    Assignee: Japan Exlan Company Limited
    Inventors: Keitaro Fukushima, Takamaro Kusunose, Yoshinori Nosaka