Patents by Inventor Tetsuya Kanbe

Tetsuya Kanbe 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: 6403242
    Abstract: The present invention provides a magnetic recording medium having a magnetic layer deposited on a substrate through a single-layer underlayer or a multilayer-underlayer, the magnetic layer includes magnetic crystal grains having an acicular structure or amorphous magnetic particles, an average grain size of the magnetic grain and a grain-size dispersion normalized by the average grain size are less than 16 nm and less than 0.5, respectively, a value Ku·v/kT which results from dividing a product of a magnetic anisotropy constant Ku and a volume v of the magnetic grain by a product of a Boltzmann constant k and an absolute temperature T is selected to be greater than 60, and a film thickness of the magnetic layer falls within twice of the average grain size.
    Type: Grant
    Filed: March 14, 2000
    Date of Patent: June 11, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Tetsuya Kanbe, Yoshio Takahashi, Akira Ishikawa, Ichiro Tamai, Yuzuru Hosoe, Yoshifumi Matsuda, Kiwamu Tanahashi, Tomoo Yamamoto
  • Patent number: 6403240
    Abstract: A magnetic recording system includes an in-plane magnetic recording medium having a magnetic layer fabricated on a single underlayer or on a plurality of underlayers respectively fabricated on a substrate; a driver unit for driving the in-plane magnetic recording medium in a write direction; a magnetic head having a read unit and a write unit; a unit for moving the magnetic head relative to the in-plane magnetic recording medium; and a read/write signal processing unit for reading an output signal from the magnetic head and writing an input signal to the magnetic recording media, wherein the read unit of the magnetic head is a magnetoresistive head and the single underlayer or at least one of the plurality of underlayers is made of Co-containing amorphous material or fine crystal material, or is made of alloy material, the alloy material having as the main components at least one element selected from a group consisting of Cr, Mo, V and Ta and containing at least one element selected from a group consisting o
    Type: Grant
    Filed: May 19, 1997
    Date of Patent: June 11, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Tetsuya Kanbe, Akira Ishikawa, Ichiro Tamai, Yotsuo Yahisa, Yuzuru Hosoe, Kiwamu Tanahashi, Yoshibumi Matsuda, Hiroyuki Kataoka, Toshinori Ono, Shinji Fukaya, Kazuhiro Ura, Naoto Endo, Tomoo Yamamoto
  • Publication number: 20020064691
    Abstract: The longitudinal magnetic recording medium includes a non-magnetic substrate, a first underlayer having at least one of an amorphous structure and a fine crystal structure formed on the non-magnetic substrate, a second underlayer having a body-centered cubic structure formed on the first underlayer, a third underlayer having a hexagonal closed packed structure formed on the second underlayer, and a magnetic layer having the hexagonal closed packed structure formed on the third underlayer, wherein the third underlayer is composed of an alloy containing Co and Ru.
    Type: Application
    Filed: June 26, 2001
    Publication date: May 30, 2002
    Inventors: Tetsuya Kanbe, Yotsuo Yahisa, Yoshibumi Matsuda, Jo Inagaki, Koji Sakamoto
  • Publication number: 20010024743
    Abstract: In a magnetic storage apparatus having a magnetic recording medium, a drive unit for driving this medium in a prespecified recording direction, a magnetic head assembly including a recorder section and reproduction section, means for causing the magnetic head to move relatively with respect to the magnetic record medium, and a record/playback signal processor means for performing signal inputting to the magnetic head and for effecting reproduction of an output signal from the magnetic head, the reproduction section of said magnetic head is composed of a magnetic head of the magnetoresistance effect type, while said magnetic record medium is structured including a substrate and a magnetic layer formed thereover with one or several underlayers being sandwiched therebetween, wherein at least one of the underlayers is a specific layer that is made of amorphous or microcrystalline materials containing therein Ni as the principal or main component thereof and further containing at least one kind of element as selec
    Type: Application
    Filed: March 6, 2001
    Publication date: September 27, 2001
    Inventors: Tetsuya Kanbe, Ichiro Tamai, Yuzuru Hosoe, Kiwamu Tanahashi, Yoshio Takahashi, Fumiyoshi Kirino, Nagatugu Koiso, Satoshi Matsunuma
  • Publication number: 20010008716
    Abstract: A magnetic recording medium having first undercoating layers 40, 40′ formed directly or via substrate face undercoating layers on a substrate 40, second undercoating layers 42, 42′ directly formed on the first undercoating layers 40, 40′, magnetic films 43, 43′ formed on the second undercoating layers 42, 42′, and protective films 44, 44′ formed on the magnetic films 43, 43′. Clusters having a large amount of oxygen are dispersed on the boundary face of the first and second undercoating layers. Preferably, the first undercoating layer is made of an alloy which includes two kinds of elements in which the difference between oxide formation standard free energies &Dgr;G° of the elements at the temperature of 250° C. is large.
    Type: Application
    Filed: February 16, 2001
    Publication date: July 19, 2001
    Inventors: Yoshibumi Matsuda, Akira Ishikawa, Yotsuo Yahisa, Yuzuru Hosoe, Tetsuya Kanbe, Koji Sakamoto
  • Patent number: 6221508
    Abstract: In a magnetic storage apparatus having a magnetic recording medium, a drive unit for driving this medium in a prespecified recording direction, a magnetic head assembly including a recorder section and reproduction section, means for causing the magnetic head to move relatively with respect to the magnetic record medium, and a record/playback signal processor means for performing signal inputting to the magnetic head and for effecting reproduction of an output signal from the magnetic head, the reproduction section of said magnetic head is composed of a magnetic head of the magneto-resistance effect type, while said magnetic record medium is structured including a substrate and a magnetic layer formed thereover with one or several underlayers being sandwiched therebetween, wherein at least one of the underlayers is a specific layer that is made of amorphous or microcrystalline materials containing therein Ni as the principal or main component thereof and further containing at least one kind of element as sele
    Type: Grant
    Filed: December 8, 1998
    Date of Patent: April 24, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Tetsuya Kanbe, Ichiro Tamai, Yuzuru Hosoe, Kiwamu Tanahashi, Yoshio Takahashi, Fumiyoshi Kirino, Nagatugu Koiso, Satoshi Matsunuma
  • Patent number: 6197367
    Abstract: A magnetic recording medium having first undercoating layers 40, 40′ formed directly or via substrate face undercoating layers on a substrate 40, second undercoating layers 42, 42′ directly formed on the first undercoating layers 40, 40′, magnetic films 43, 43′ formed on the second undercoating layers 42, 42′, and protective films 44, 44′ formed on the magnetic films 43, 43′. Clusters having a large amount of oxygen are dispersed on the boundary face of the first and second undercoating layers. Preferably, the first undercoating layer is made of an alloy which includes two kinds of elements in which the difference between oxide formation standard free energies &Dgr;G° of the elements at the temperature of 250° C. is large.
    Type: Grant
    Filed: October 29, 1997
    Date of Patent: March 6, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Yoshibumi Matsuda, Akira Ishikawa, Yotsuo Yahisa, Yuzuru Hosoe, Tetsuya Kanbe, Koji Sakamoto
  • Patent number: 6080476
    Abstract: It is an object of the present invention to provide a magnetic recording medium which has a magnetic layer deposited on a substrate through a single-layer underlayer or a multilayer-underlayer, the magnetic layer includes magnetic crystal grains having an acicular structure or amorphous magnetic particles, an average grain size of the magnetic grain and a grain-size dispersion normalized by the average grain size are less than 16 nm and less than 0.5, respectively, a value Ku.multidot.v/kT which results from dividing a product of a magnetic anisotropy constant Ku and a volume v of the magnetic grain by a product of a Boltzmann constant k and an absolute temperature T is selected to be greater than 60, and a film thickness of the magnetic layer falls within twice of the average grain size.
    Type: Grant
    Filed: March 25, 1998
    Date of Patent: June 27, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Tetsuya Kanbe, Yoshio Takahashi, Akira Ishikawa, Ichiro Tamai, Yuzuru Hosoe, Yoshifumi Matsuda, Kiwamu Tanahashi, Tomoo Yamamoto
  • Patent number: 6001447
    Abstract: The magnetic storage apparatus has a high reliability at a recording density of 2 gigabits or more per square inch. The longitudinal recording media necessary to realize the apparatus has a low media noise and is immune from the influence of thermal fluctuations. The magnetic storage apparatus has a longitudinal magnetic recording media including a magnetic layer which is formed on a substrate via a multi-layered underlayer; a driver for driving the recording media in a recording direction; a magnetic head including a recording section and a read-back section; a driver for moving the magnetic head relatively with respect to the longitudinal magnetic recording media; and a read/write signal processor for processing input signals to the magnetic head and output signal read-back therefrom. The read-back section of the magnetic head includes a magnetoresistive head.
    Type: Grant
    Filed: January 8, 1998
    Date of Patent: December 14, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Kiwamu Tanahashi, Yuzuru Hosoe, Ichiro Tamai, Tetsuya Kanbe, Tomoo Yamamoto, Masukazu Igarashi, Yoshio Takahashi
  • Patent number: 5922456
    Abstract: A longitudinal magnetic recording medium and a magnetic storage apparatus using the longitudinal magnetic recording medium. The recording medium has a multi-layered underlayer and a magnetic layer formed on it. The underlayer has a first layer of a body-centered cubic structure, a second layer of a hexagonal-close packed structure formed on the first layer, and a third layer of a bcc structure formed on the second layer. The underlayer may further have a fourth layer of an hcp structure layer formed on the third layer.
    Type: Grant
    Filed: September 3, 1997
    Date of Patent: July 13, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Kiwamu Tanahashi, Yuzuru Hosoe, Ichiro Tamai, Tetsuya Kanbe, Tomoo Yamamoto
  • Patent number: 5470563
    Abstract: A skin irritation alleviation agent composed of a polyoxyalkylene-modified organopolysiloxane is provided. Various compositions including skin external application compositions, cosmetic or similar compositions (e.g., an adhesive composition for a false eyelash, a decolorant composition, a depilatory composition, and an eyeliner composition) containing a polyoxyalkylene-modified organosiloxane are also provided. This alleviation agent has a low skin irritation effect and extremely high safety factor when used on the human body.
    Type: Grant
    Filed: November 28, 1989
    Date of Patent: November 28, 1995
    Assignee: Shiseido Company Ltd.
    Inventors: Hiroshi Tanaka, Toshiaki Kobayashi, Tomiyuki Nanba, Masaaki Ishiwatari, Toshio Yoneyama, Kimio Ohno, Takashi Matsumoto, Tetsuya Kanbe, Takashi Isa, Yoshiyuki Ogusu