Patents by Inventor Satoshi Matunuma

Satoshi Matunuma 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 medium, method for producing the same, and magnetic recording apparatus
    Publication number: 20040185308
    Abstract: A magnetic recording medium based on the perpendicular magnetic recording system has a substrate which is formed of a non-magnetic material, a soft magnetic back layer which is formed of a soft magnetic material and which is formed on the substrate, an underlayer which is formed on the soft magnetic back layer, and a recording layer which is formed of an alloy magnetic material which is mainly composed of CoPtCr and contains an oxide, and which is formed on the underlayer. The recording layer is formed of two or more magnetic layers having different oxide contents, and the layer, which is included in the two or more magnetic layers for constructing the recording layer and which is provided on a side nearest to the underlayer, has the highest oxide content in the recording layer. The magnetic recording medium has more excellent magnetic characteristics with less medium noise.
    Type: Application
    Filed: January 28, 2004
    Publication date: September 23, 2004
    Applicant: HITACHI MAXELL, LTD.
    Inventors: Tetsunori Koda, Hideaki Yamanaka, Enji Fujita, Satoshi Matunuma