Patents Assigned to Shun-Ichi Iwasaki
  • Patent number: 4210946
    Abstract: A magnetic recording medium suitable for use in a recording system employing a magnetic recording transducer or head of the single-pole type which operates in a perpendicular magnetization mode comprises a non-magnetic base supporting a layer of low coercive force material formed on the base and which underlies a magnetic recording layer. The magnetic recording layer which faces the magnetic recording transducer or head is formed of an alloy composed mainly of chromium and cobalt and has an easy axis of magnetization perpendicular to the surface of the magnetic recording layer, with the thickness of the latter being no greater than 3.0 microns. The low coercive force material layer has a coercive force no greater than 1/5 of the coercive force of the magnetic recording layer, and the thickness of the low coercive force layer is greater than 0.1 microns.
    Type: Grant
    Filed: September 19, 1978
    Date of Patent: July 1, 1980
    Assignees: Sony Corporation, Fujitsu Limited, Shun-Ichi Iwasaki
    Inventors: Shun-Ichi Iwasaki, Yoshihisa Nakamura