Patents by Inventor Hisato Shibata

Hisato Shibata 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).

  • Patent number: 8374070
    Abstract: Disclosed is a magnetic recording medium comprising a substrate, a magnetic recording layer formed on the substrate to record magnetic information, and a piezoelectric material disposed adjacent to the magnetic recording layer and capable of contracting and expanding. Preferably, piezoelectric members made of the piezoelectric material are formed in such a manner as to be spaced a predetermined distance apart from each other on the substrate in a direction crossing a track on the magnetic recording layer, and the magnetic recording layer is formed between the piezoelectric members. When subjected to laser light or ultraviolet radiation, the piezoelectric material contracts or expands at least in the direction crossing the track. The piezoelectric material is selected from the group consisting of lead lanthanum zirconate titanate, barium titanate, and potassium niobate.
    Type: Grant
    Filed: October 12, 2007
    Date of Patent: February 12, 2013
    Assignee: Showa Denko K.K.
    Inventors: Hisato Shibata, Hideaki Takahoshi, Yuki Yoshida, Akira Kikuchi
  • Publication number: 20100246045
    Abstract: Disclosed is a magnetic recording medium comprising a substrate, a magnetic recording layer formed on the substrate to record magnetic information, and a piezoelectric material disposed adjacent to the magnetic recording layer and capable of contracting and expanding. Preferably, piezoelectric members made of the piezoelectric material are formed in such a manner as to be spaced a predetermined distance apart from each other on the substrate in a direction crossing a track on the magnetic recording layer, and the magnetic recording layer is formed between the piezoelectric members. When subjected to laser light or ultraviolet radiation, the piezoelectric material contracts or expands at least in the direction crossing the track. The piezoelectric material is selected from the group consisting of lead lanthanum zirconate titanate, barium titanate, and potassium niobate.
    Type: Application
    Filed: October 12, 2007
    Publication date: September 30, 2010
    Applicant: SHOWA DENKO K.K.
    Inventors: Hisato Shibata, Hideaki Takahoshi, Yuki Yoshida, Akira Kikuchi
  • Publication number: 20090142624
    Abstract: A method of producing a magnetic recording medium produces a medium having a magnetic recording layer disposed above a nonmagnetic intermediate layer, The nonmagnetic intermediate layer is formed by a sputtering using a target made of an oxide material. Oxygen gas or carbon dioxide gas is supplied during the sputtering in order to suppress a state where an oxygen supply becomes insufficient due to separation of oxygen atoms from the oxide material at a time of plasma generation.
    Type: Application
    Filed: November 29, 2008
    Publication date: June 4, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Hideaki TAKAHOSHI, Hisato Shibata, Shinya Sato, Isatake Kaitsu, Akira Kikuchi
  • Publication number: 20090109579
    Abstract: A magnetic recording medium has a substrate, a first granular layer formed on the substrate, the first granular layer having a plurality of a first magnetic grains and a first oxide for separating the plurality of first magnetic grains from one another. A non-magnetic layer is formed on the first granular layer. The second granular layer is formed on the non-magnetic layer which has a plurality of second magnetic grains and a second oxide for separating the plurality of second magnetic grains from one another. The anisotropic magnetic field of the first granular layer is more intensive than that of the second granular layer.
    Type: Application
    Filed: August 26, 2008
    Publication date: April 30, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Hideaki Takahoshi, Hisato Shibata, Shinya Sato, Isatake Kaitsu, Akira Kikuchi
  • Publication number: 20090110961
    Abstract: A magnetic recording medium used for a hard disc drive and the like, a method of manufacturing the same, and a magnetic storage device. The magnetic recording medium that includes a substrate, a first ferromagnetic layer formed on the substrate, a non-magnetic layer formed on the first ferromagnetic layer and including a ferromagnetic element and a second ferromagnetic layer formed on the non-magnetic layer, wherein the first ferromagnetic layer and the second ferromagnetic layer are magnetically coupled through the non-magnetic layer.
    Type: Application
    Filed: October 29, 2008
    Publication date: April 30, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Hisato Shibata, Hideaki Takahoshi, Shinya Sato, Isatake Kaitsu, Akira Kikuchi
  • Publication number: 20080292909
    Abstract: This magnetic recording medium has a substrate, a nonmagnetic granular layer formed above the substrate and a recording layer formed on the nonmagnetic granular layer. The nonmagnetic granular layer is made of CoCr alloy with an hcp or an fcc crystal structure in which a nonmagnetic material segregates virtually-columnar magnetic grains. The magnetic recording medium and the magnetic storage apparatus in which the medium is used have improved reading/writing performances.
    Type: Application
    Filed: May 2, 2008
    Publication date: November 27, 2008
    Applicant: FUJITSU LIMITED
    Inventors: Satoshi Igarashi, Akira Kikuchi, Isatake Kaitsu, Ryosaku Inamura, Kenji Sato, Shinya Sato, Hideaki Takahoshi, Atsushi Endo, Hisato Shibata