Patents by Inventor Masahiro Kitada

Masahiro Kitada 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).

  • Thin-film permanent magnet and method of producing the same
    Patent number: 4596646
    Abstract: A thin-film permanent magnet which is made of a Co - Pt alloy containing 5-35 atomic-% of Pt. This thin-film permanent magnet can be readily produced by a sputtering method in which the ultimate pressure before the introduction of a sputtering gas is made 5.times.10.sup.-7 -1.times.10.sup.-4 Torr. Without any heat treatment, it has a coercivity of 2,000 Oe at the maximum and a remanence of about 8,000-about 18,000 G.
    Type: Grant
    Filed: February 23, 1983
    Date of Patent: June 24, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Masahiro Kitada, Hiroshi Yamamoto, Masahide Suenaga, Noboru Shimizu
  • Perpendicular magnetic recording medium
    Patent number: 4544591
    Abstract: In a perpendicular magnetic recording medium comprising a high permeability film and a perpendicular magnetization film which are laminated on a non-magnetic substrate, a perpendicular magnetic recording medium is provided wherein a permanent magnet film is further sandwiched between the non-magnetic substrate and the high permeability film, thereby eliminating a spike noise.
    Type: Grant
    Filed: September 30, 1983
    Date of Patent: October 1, 1985
    Assignees: Hitachi, Ltd, Hitachi Maxell, Ltd.
    Inventors: Yasutaro Uesaka, Sadao Hishiyama, Masahiro Kitada, Noboru Shimizu, Hideo Tanabe, Hideo Fujiwara
  • Formation of electrodes for magnetoresistive sensor
    Patent number: 4411757
    Abstract: Electrodes for a magnetoresistive sensor can be formed easily by a method wherein a double-layer structure of Mo and Al on a film of a magnetoresistive material such as permalloy is formed to have a predetermined pattern, firstly by exposing an Al layer to a chemical etching solution or subjecting the Al layer to the ion-milling treatment to give said Al layer said pattern and then subjecting a Mo layer to the plasma etching or reactive sputter etching treatment to give said Mo layer said pattern.
    Type: Grant
    Filed: June 8, 1982
    Date of Patent: October 25, 1983
    Assignee: Hitachi, Ltd.
    Inventors: Masahiro Kitada, Masahide Suenaga, Yukihisa Tsukada, Noboru Shimizu, Hiroshi Yamamoto