Patents by Inventor Kei Hirata

Kei Hirata 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: 8785542
    Abstract: The present invention relates to a rubber composition including (A) at least one rubber component selected from the group consisting of a synthetic rubber and a natural rubber; (B) a polymer of farnesene having a weight-average molecular weight of not less than 2,000 and less than 25,000; and (C) carbon black.
    Type: Grant
    Filed: September 21, 2012
    Date of Patent: July 22, 2014
    Assignees: Kuraray Co., Ltd., Amyris, Inc.
    Inventors: Shigenao Kuwahara, Kei Hirata, Daisuke Koda
  • Publication number: 20140155536
    Abstract: The present invention relates to a rubber composition including (A) at least one rubber component selected from the group consisting of a synthetic rubber and a natural rubber; (B) a polymer of farnesene having a weight-average molecular weight of not less than 2,000 and less than 25,000; and (C) carbon black.
    Type: Application
    Filed: September 21, 2012
    Publication date: June 5, 2014
    Applicants: AMYRIS, INC., KURARAY CO., LTD.
    Inventors: Shigenao Kuwahara, Kei Hirata, Daisuke Koda
  • Patent number: 8724264
    Abstract: A thin film magnetic head including a magnetoresistive element (MR) having higher reading performance. In manufacturing the thin film magnetic head, after forming an MR element, a pair of magnetic domain controlling layers are formed by stacking a buffer layer, a magnetic bias layer and a first cap layer in this order on both sides, in a track-width direction, of the MR element via an insulating layer, respectively. Then, a second cap layer is formed to cover the upper surface of the MR element and connect the pair of cap-layers. Then, a gap adjustment layer and a top shielding layer are formed to cover the pair of first cap layers and the second cap layer, completing a read head section.
    Type: Grant
    Filed: September 4, 2008
    Date of Patent: May 13, 2014
    Assignee: TDK Corporation
    Inventors: Kei Hirata, Takayasu Kanaya, Kosuke Tanaka, Shinji Hara
  • Patent number: 8675457
    Abstract: A near-field light generator includes a waveguide, a plasmon generator, and an MgO layer. The waveguide includes a core and a cladding. The plasmon generator has an outer surface including a plasmon exciting part and a near-field light generating part, and is configured so that a surface plasmon is excited on the plasmon exciting part based on light propagating through the core, and the near-field light generating part generates near-field light based on the surface plasmon. The MgO layer is in contact with at least part of the outer surface of the plasmon generator excluding the near-field light generating part, and not in contact with the core. The cladding is lower in refractive index than the core and the MgO layer.
    Type: Grant
    Filed: November 28, 2012
    Date of Patent: March 18, 2014
    Assignee: TDK Corporation
    Inventors: Kei Hirata, Keita Kawamori, Nobuyuki Mori, Kosuke Tanaka
  • Patent number: 8676093
    Abstract: A developing device includes a first developer containing chamber, a second developer containing chamber, a first inflow section, a second inflow section, a first conveyance member and a second conveyance member. The first inflow section allows the developer to flow from the second developer containing chamber into the first developer containing chamber. The second inflow section allows the developer to flow from the first developer containing chamber into the second developer containing chamber. The first conveyance member conveys the developer contained in the first developer containing chamber in a first developer conveyance direction. The second conveyance member conveys the developer contained in the second developer containing chamber in a second developer conveyance direction.
    Type: Grant
    Filed: October 8, 2010
    Date of Patent: March 18, 2014
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Takashi Sakamoto, Kei Hirata, Akihide Kawamura, Naoya Iwata
  • Patent number: 8665548
    Abstract: A magnetic disk device includes: a recording medium provided with a plurality of write tracks; a magnetic write head including a magnetic pole, side shields, and a leading shield, a distance from the magnetic pole to each of the side shields being maintained to be uniform with a gap layer therebetween, and a distance from the magnetic pole to the leading shield being maintained to be uniform with a gap layer therebetween; and a control section rotating the recording medium, and allowing magnetic information to be recorded on the recording medium while allowing the magnetic write head to travel in a direction from an inner write track toward an outer write track or in a direction from the outer write track toward the inner write track, across write tracks in the recording medium. With such a configuration, format efficiency may be improved, and a width of an erase band on a magnetic disk may be minimized.
    Type: Grant
    Filed: March 14, 2011
    Date of Patent: March 4, 2014
    Assignee: TDK Corporation
    Inventors: Kei Hirata, Hiroshi Kiyono, Osamu Nakada, Kenkichi Anagawa
  • Publication number: 20140043948
    Abstract: A plasmon-generator of the invention is configured to include a first configuration member including a near-field light generating end surface; and a second configuration member joined and integrated with the first configuration member and not including the near-field light generating end surface. The first configuration member is configured to contain Au as a primary component and to contain any one or more elements selected from a group of Co, Fe, Sb, Nb, Zr, Ti, Hf, and Ta, and is configured so that a content percentage X1 of the contained element is within a range between 0.2 at % or more and 2.0 at % or less. Thereby, thermostability, optical characteristic, and the process stability are satisfied. Also, heat dissipation and heat generation suppression effect are extremely superior.
    Type: Application
    Filed: August 7, 2012
    Publication date: February 13, 2014
    Applicant: TDK CORPORATION
    Inventors: Kei HIRATA, Ryo HOSOI, Keita KAWAMORI, Tetsuya ROPPONGI
  • Patent number: 8605387
    Abstract: A thermally-assisted magnetic recording head includes a magnetic pole and a heating element. The magnetic pole has a front end face located in a medium facing surface. The magnetic pole forms on a track a distribution of write magnetic field strength that peaks at a first position on the track. The heating element forms on the track a distribution of temperature that peaks at a second position on the track. The first position is located on the trailing side relative to the second position. The front end face of the magnetic pole has a main portion and first and second extended portions. The first and second extended portions are extended in the track width direction from the main portion at positions on the leading side relative to the center of the main portion in the direction of travel of a magnetic recording medium.
    Type: Grant
    Filed: March 5, 2012
    Date of Patent: December 10, 2013
    Assignee: TDK Corporation
    Inventors: Kei Hirata, Kosuke Tanaka, Tetsuya Roppongi
  • Patent number: 8588040
    Abstract: A thermally assisted magnetic head slider includes an air bearing surface facing to a magnetic recording medium, a read portion, and a write portion including a write element, a waveguide for guiding light generated by the light source module, and a plasmon unit provided around the write portion and the waveguide. A first coat layer with a first thickness which has a first light absorption index is covered on an opposed-to-medium surface of the read portion, and a second coat layer with a second thickness which has a second light absorption index is covered on an opposed-to medium surface of the write portion, wherein the second thickness is larger than the first thickness, and the second light absorption index is smaller than the first light absorption index. The slider can protect the write portion and improve the reading performance of the read portion.
    Type: Grant
    Filed: December 21, 2012
    Date of Patent: November 19, 2013
    Assignees: SAE Magnetics (H.K.) Ltd., TDK Corporation
    Inventors: Yasutoshi Fujita, Ryuji Fujii, Hideki Tanzawa, Natsuo Nishijima, Tai Boon Lee, Jian Hui Huang, Huan Chao Liang, Koji Shimazawa, Kei Hirata, Daisuke Miyauchi
  • Patent number: 8582239
    Abstract: A microwave assisted magnetic head includes a main magnetic pole; a trailing shield, a main coil for causing the main magnetic pole to generate a perpendicular recording field, at least one secondary coil for generating an in-plane alternate-current (AC) magnetic field with a frequency in a microwave band from a magnetic recording gap between the main magnetic pole and the trailing shield, nonmagnetic films formed on magnetic recording gap facing surfaces that are defined by the main magnetic pole and the trailing shield, the main magnetic pole and the trailing shield being configured with first soft magnetic films, and second soft magnetic films formed further on the surfaces of the nonmagnetic films. The second soft magnetic films have larger anisotropy fields than the first soft magnetic films have.
    Type: Grant
    Filed: June 20, 2012
    Date of Patent: November 12, 2013
    Assignee: TDK Corporation
    Inventors: Yoshikazu Soeno, Kei Hirata, Tsutomu Aoyama, Isamu Sato
  • Patent number: 8568908
    Abstract: A method for manufacturing a magnetic film includes preparing a foundation layer containing a noble metal element and a base metal element, and depositing a plated layer of a magnetic material on the foundation layer by pulse plating.
    Type: Grant
    Filed: June 19, 2007
    Date of Patent: October 29, 2013
    Assignee: TDK Corporation
    Inventors: Kei Hirata, Atsushi Yamaguchi, Shingo Miyata
  • Patent number: 8570843
    Abstract: The present invention provides a thermally assisted magnetic head with improved recording performance. The thermally assisted magnetic head includes a recording element and a near-field light generating element. The recording element includes a main pole appearing on a medium-facing surface, and a bit inversion starting region intended to be a maximum recording magnetic field generating position is formed at a leading edge of the main pole. The near-field light generating element is located on a leading side of the main pole and capable of creating a heating spot due to a near-field light on a near-field light generating end face appearing on the medium-facing surface. The bit inversion starting region is located within one-half of a diameter of the heating spot from a center of the heating spot.
    Type: Grant
    Filed: February 22, 2012
    Date of Patent: October 29, 2013
    Assignee: TDK Corporation
    Inventors: Kei Hirata, Kosuke Tanaka, Tsutomu Chou, Susumu Aoki, Makoto Isogai, Tetsuya Roppongi
  • Patent number: 8559133
    Abstract: A perpendicular magnetic write head includes: a magnetic pole having an end face on an air bearing surface; and side shield layers each having an end face on the air bearing surface, and arranged on both sides, in a write track width direction, of the magnetic pole with a side gap in between. The end face of the magnetic pole has a geometry in which a width at a trailing edge is larger than a width at a leading edge. Relationship D1<D2, D1<D3, and D3?D2 are satisfied in the air bearing surface, where D1 is a gap length of the side gap at the trailing edge, D2 is a gap length of the side gap at the leading edge, and D3 is a gap length of the side gap at any position between the trailing edge and the leading edge.
    Type: Grant
    Filed: June 1, 2009
    Date of Patent: October 15, 2013
    Assignee: TDK Corporation
    Inventors: Kei Hirata, Takeo Kagami, Tatsuhiro Nojima, Hisayoshi Watanabe, Michitaka Nishiyama
  • Patent number: 8559123
    Abstract: This magnetic recording device is provided with a magnetic write head having a magnetic pole, and a magnetic recording medium having a plurality of data recording blocks. Each of the data recording blocks is formed with a plurality of write tracks, and separated, in a write track width direction, from neighboring one of the data recording blocks with a writing exudation suppression section in between. With this configuration, a magnetic mutual interference of the adjacent data recording blocks at the time of a data rewriting process is avoided even when a mutual interval of the data recording blocks is narrowed, and a good recording state is maintained in each of the data recording blocks. Therefore, it is possible to achieve an improvement in a recording density, while realizing the good and brief data rewriting process for each of the data recording blocks.
    Type: Grant
    Filed: June 14, 2010
    Date of Patent: October 15, 2013
    Assignee: TDK Corporation
    Inventors: Kei Hirata, Norikazu Ota, Noboru Yamanaka
  • Publication number: 20130229730
    Abstract: A thermally-assisted magnetic recording head includes a magnetic pole and a heating element. The magnetic pole has a front end face located in a medium facing surface. The magnetic pole forms on a track a distribution of write magnetic field strength that peaks at a first position on the track. The heating element forms on the track a distribution of temperature that peaks at a second position on the track. The first position is located on the trailing side relative to the second position. The front end face of the magnetic pole has a main portion and first and second extended portions. The first and second extended portions are extended in the track width direction from the main portion at positions on the leading side relative to the center of the main portion in the direction of travel of a magnetic recording medium.
    Type: Application
    Filed: March 5, 2012
    Publication date: September 5, 2013
    Applicant: TDK CORPORATION
    Inventors: Kei HIRATA, Kosuke TANAKA, Tetsuya ROPPONGI
  • Publication number: 20130215725
    Abstract: The present invention provides a thermally assisted magnetic head with improved recording performance. The thermally assisted magnetic head includes a recording element and a near-field light generating element. The recording element includes a main pole appearing on a medium-facing surface, and a bit inversion starting region intended to be a maximum recording magnetic field generating position is formed at a leading edge of the main pole. The near-field light generating element is located on a leading side of the main pole and capable of creating a heating spot due to a near-field light on a near-field light generating end face appearing on the medium-facing surface. The bit inversion starting region is located within one-half of a diameter of the heating spot from a center of the heating spot.
    Type: Application
    Filed: February 22, 2012
    Publication date: August 22, 2013
    Applicant: TDK CORPORATION
    Inventors: Kei HIRATA, Kosuke Takana, Tsutomu Chou, Susumu Aoki, Makoto Isogai, Tetsuya Roppongi
  • Patent number: 8503270
    Abstract: A thermally-assisted magnetic recording head includes a magnetic pole, a waveguide, and a plasmon generator. The plasmon generator and the magnetic pole are disposed to align in the direction of travel of a magnetic recording medium. The thermally-assisted magnetic recording head further includes an amorphous layer made of a nonmagnetic metal, the amorphous layer being interposed between and in contact with the plasmon generator and the magnetic pole.
    Type: Grant
    Filed: April 26, 2012
    Date of Patent: August 6, 2013
    Assignee: TDK Corporation
    Inventors: Keita Kawamori, Kei Hirata, Tetsuya Roppongi
  • Patent number: 8472150
    Abstract: A giant magneto-resistive effect device (CPP-GMR device) having the CPP (current perpendicular to plane) structure comprising a spacer layer, and a first ferromagnetic layer and a second ferromagnetic layer stacked one upon another with the spacer layer interposed between them, with a sense current applied in a stacking direction, wherein the spacer layer comprises a first nonmagnetic metal layer and a second nonmagnetic metal layer, each made of a nonmagnetic metal material, and a semiconductor oxide layer interposed between the first nonmagnetic metal layer and the second nonmagnetic metal layer, the semiconductor oxide layer that forms a part of the spacer layer contains zinc oxide as its main component wherein the main component zinc oxide contains an additive metal, and the additive metal is less likely to be oxidized than zinc.
    Type: Grant
    Filed: January 3, 2008
    Date of Patent: June 25, 2013
    Assignee: TDK Corporation
    Inventors: Yoshihiro Tsuchiya, Tomohito Mizuno, Kei Hirata, Koji Shimazawa, Shinji Hara
  • Patent number: 8472137
    Abstract: The present invention relates to a magnetic head, a manufacturing method therefor, a head assembly, and a magnetic recording/reproducing apparatus. According to the present invention, it includes a magnetic pole layer, a non-magnetic layer, a trailing gap layer, and a trailing shield layer. The magnetic pole layer has a pole tip exposed on a magnetic medium-facing surface. The non-magnetic layer is laid on the magnetic pole layer. The trailing shield layer is exposed on the magnetic medium-facing surface and laid over the magnetic pole layer and the non-magnetic layer with the trailing gap layer between. The magnetic pole layer and the non-magnetic layer have a continuous tapered face opposed to a lower side of the trailing shield layer. Moreover, the tapered face extends from a trailing edge of the pole tip at a constant inclination angle.
    Type: Grant
    Filed: July 28, 2010
    Date of Patent: June 25, 2013
    Assignee: TDK Corporation
    Inventors: Kei Hirata, Kenkichi Anagawa, Michitaka Nishiyama, Hideyuki Yatsu, Shin Narushima, Hisayoshi Watanabe, Tatsuhiro Nojima
  • Patent number: 8462594
    Abstract: A thermally-assisted magnetic recording head includes a medium facing surface, a magnetic pole, a waveguide including a core and a cladding, and a plasmon generator. The magnetic pole is located forward of the core in the direction of travel of a magnetic recording medium. The plasmon generator is disposed between the core and the magnetic pole. The core has an evanescent light generating surface facing toward the plasmon generator. The plasmon generator has a front end face located in the medium facing surface, a flat surface facing toward the'evanescent light generating surface, and first and second side surfaces that are at a distance from each other and are located farther from the evanescent light generating surface than is the flat surface.
    Type: Grant
    Filed: February 27, 2012
    Date of Patent: June 11, 2013
    Assignee: TDK Corporation
    Inventors: Susumu Aoki, Kosuke Tanaka, Tetsuya Roppongi, Kei Hirata, Takeshi Tsutsumi