Patents by Inventor Keitaro Sakai

Keitaro Sakai 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).

  • Magnetic powder for magnetic recording medium
    Patent number: 4423114
    Abstract: A magnetic powder for a magnetic recording medium which is a cobalt-adsorbed magnetic iron oxide having a coercive force of 1000 Oe or more and a ratio of a coercive force at -196.degree. C. to a coercive force at room temperature of 3 or less.
    Type: Grant
    Filed: September 9, 1981
    Date of Patent: December 27, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Hiroto Saguchi, Masashi Hayama, Keitaro Sakai