Patents by Inventor Masafumi Matsunaka

Masafumi Matsunaka 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).

  • Silicon nitride sintered body and process for preparation thereof
    Patent number: 5219500
    Abstract: Disclosed is a silicon nitride sintered body comprising 85 to 99 mole % of .beta.-Si.sub.3 N.sub.4, 1 to 5 mole % as the oxide (M.sub.2 O.sub.3) of at least one compound of an element (M) selected from the group consisting of Sc, Vb, Er, Ho and Dy and less than 10 mole % of excessive oxygen (O.sub.2) based on the three components, wherein the excessive oxygen/M.sub.2 O.sub.3 molar ratio is lower than 2.
    Type: Grant
    Filed: December 6, 1989
    Date of Patent: June 15, 1993
    Assignee: Kyocera Corporation
    Inventors: Makoto Yoshida, Masahiro Sato, Kazunori Koga, Kazumi Osamura, Shoji Kousaka, Tatsumi Maeda, Kiyoshi Yokoyama, Masafumi Matsunaka
  • Silicon nitride sintered body and process for preparation thereof
    Patent number: 4920085
    Abstract: Disclosed is a silicon nitride sintered body comprising 85 to 99 mol % of .beta.-Si.sub.3 N.sub.4, 1 to 5 mol % as the oxide (M.sub.2 O.sub.3) of at least one compound of an element (M) selected from the group consisting of Sc, Vb, Er, Ho and Dy and less than 10 mol % of excessive oxygen (O.sub.2) based on the three components, wherein the excessive oxygen/M.sub.2 O.sub.3 molar ratio is lower than 2.
    Type: Grant
    Filed: April 1, 1988
    Date of Patent: April 24, 1990
    Assignee: Kyocera Corporation
    Inventors: Makoto Yoshida, Masahiro Sato, Kazunori Koga, Kazumi Osamura, Shoji Kousaka, Tatsumi Maeda, Kiyoshi Yokoyama, Masafumi Matsunaka