Patents by Inventor Yasuaki Yoshioka

Yasuaki Yoshioka 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 recording powder having a high coercive force at room temperatures and a low curie point
    Patent number: 5211770
    Abstract: A magnetic recording powder for use as a material for magnetic recording media including magnetic tapes and magnetic cards, the powder having a high coercive force at room temperatures and a low Curie point, consists of at least one element selected from the group consisting of Y and rare-earth elements (R): 5-20 atomic %, B: 5-20 atomic %, Mn: 4-20 atomic %; and Fe and inevitable impurities: the balance. If required, the powder may further contain Al: 1-10 atomic %, and/or Cr: 1-10 atomic %. The powder has a mean particle size of 0.5-2 .mu.m and a mean crystal grain size of 0.1-0.4 .mu.m.
    Type: Grant
    Filed: July 29, 1992
    Date of Patent: May 18, 1993
    Assignees: Mitsubishi Materials Corporation, Nippon Telegraph and Telephone Corporation, Dai Nippon Insatsu Kabushiki Kaisha
    Inventors: Ginya Ishiguro, Kouichi Ishiyama, Yoshinari Ishii, Takuo Takeshita, Hachiro Saito, Yasuaki Yoshioka