Patents by Inventor Akira Shimokawa

Akira Shimokawa 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 oxide and process for producing same
    Patent number: 5538656
    Abstract: A magnetic oxide obtained by mixing a given amount ranging from 0.20 to 76.0% by weight of at least one member selected from among Ca, Ti, Sn, Si and Mg magnetization control (regulation) materials with hematite, a mixture of hematite and magnetite, or magnetite as a starting material to obtain a mixed powder, adding 0.1 to 4.0% by weight of a liquid or powder substance having a carbon-to-carbon single or double bond to the mixed powder, stirring the mixture to obtain a substantially homogeneous mixture and sintering the obtained mixture in an inert gas at 550.degree. to 1500.degree. C., and a process for producing the same.
    Type: Grant
    Filed: February 16, 1995
    Date of Patent: July 23, 1996
    Assignee: Fuji Electrochemical Co., Ltd.
    Inventors: Yasuhiko Mano, Takeshi Mochizuki, Isamu Sasaki, Akira Shimokawa
  • Process for producing single phase magnetite powder
    Patent number: 5512195
    Abstract: Hematite powder is mixed with a substance having a carbon-to-carbon single or double bond, and sintered in an inert gas to form magnetite powder. The magnetite powder can be provided with a desired electric resistance while retaining the properties characteristic of the magnetite powder by effecting a heating in an oxygenic atmosphere after the formation of the magnetite powder (or during a cooling subsequent to the sintering in the inert gas).
    Type: Grant
    Filed: October 3, 1994
    Date of Patent: April 30, 1996
    Assignee: Fuji Electrochemical Co. Ltd.
    Inventors: Yasuhiko Mano, Takeshi Mochizuki, Isamu Sasaki, Akira Shimokawa