Patents by Inventor Koh Itoh

Koh Itoh 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).

  • Core for inductance elements and its production method
    Patent number: 5966065
    Abstract: A core for inductance elements is formed of a sintered body of .alpha.-ferric oxide. The core has a flexural strength of at least 6 kgf/mm.sup.2 as measured by a three-point bending method, a specific resistance of at least 10.sup.6 .OMEGA..multidot.cm, a Vickers hardness of 800 to 1,500, and an iron content of 75 to 99.9 wt %, calculated as Fe.sub.2 O.sub.3. The core is produced by granulating, and forming a ferric iron powder, and holding a formed body for sintering at 950 to 1,500.degree. C. for 5 min. to 5 hours in an atmospheric environment.
    Type: Grant
    Filed: June 20, 1997
    Date of Patent: October 12, 1999
    Assignee: TDK Corporation
    Inventors: Masahiro Onizuka, Koh Itoh, Sei Kakinuma