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: 7542233
    Abstract: A perpendicular magnetic recording element includes a recording magnetic pole film and a write shield film. The recording magnetic pole film has a yoke portion and a main magnetic pole for perpendicular recording. The main magnetic pole projects from a front end of the yoke portion to have an end on a medium-facing surface. The write shield film faces the recording magnetic pole film and has a height equal to or smaller than that of the recording magnetic pole film, as measured rearward from the medium-facing surface.
    Type: Grant
    Filed: January 24, 2006
    Date of Patent: June 2, 2009
    Assignee: TDK Corporation
    Inventors: Kei Hirata, Takahiko Machita, Kiyoshi Noguchi
  • Publication number: 20090129820
    Abstract: There is provided a development apparatus including: a first developer storage container and a second developer storage container that store developer, having a first a and second openings, respectively; a first transport member provided within the first developer storage container, and that causes the developer to move to the second developer storage container via the first opening; a second transport member provided within the second developer storage container, and that causes the developer to move to the first developer storage container via the second opening; a developer holding member that performs development by causing the developer to move to a position facing an image holding body on which a latent image is formed; and a moving member provided so as to fit between an inner wall face of the second developer storage container and an outer edge of the second transport member.
    Type: Application
    Filed: May 29, 2008
    Publication date: May 21, 2009
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Hirohisa KOHNO, Kazunori Koshimori, Kei Hirata, Akihide Kawamura, Naoya Iwata, Keisuke Kubo, Takashi Sakamoto, Taiyou Uehara, Toshikazu Tsumita, Takeshi Okoshi, Tomio Onuki
  • Publication number: 20090086384
    Abstract: A magneto-resistance effect element of the present invention comprises: a pair of ferromagnetic layers whose magnetization directions change in accordance with an external magnetic field, each of the pair of ferromagnetic layers having a granular structure in which a large number of magnetic grains are distributed within a nonmagnetic matrix material; a conductive nonmagnetic intermediate layer sandwiched between the pair of ferromagnetic layers; and a bias magnetic field applying layer for exerting magnetic force on the pair of ferromagnetic layers. The matrix material in the pair of ferromagnetic layer contains conductive material.
    Type: Application
    Filed: October 2, 2007
    Publication date: April 2, 2009
    Inventors: Kei Hirata, Satoshi Miura
  • Publication number: 20090074468
    Abstract: A developing device includes: a developer carrier; a first housing chamber; a second housing chamber; a first inflow portion; a first conveying member; a second conveying member; and a concentration detecting member.
    Type: Application
    Filed: March 31, 2008
    Publication date: March 19, 2009
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Naoya IWATA, Takashi SAKAMOTO, Akihide KAWAMURA, Kei HIRATA
  • Publication number: 20090047041
    Abstract: The image forming apparatus is provided with: an image carrier; an exposure member that exposes the image carrier and forms an electrostatic latent image on the image carrier; a developing member that develops the electrostatic latent image formed on the image carrier; and a contact-retracting unit that rotates the developing member taking a predetermined position as the rotational center, and brings the developing member in contact with or proximity to the image carrier or retracts the developing member from the image carrier.
    Type: Application
    Filed: January 28, 2008
    Publication date: February 19, 2009
    Applicant: Fuji Xerox Co., Ltd.
    Inventors: Keisuke KUBO, Kei Hirata, Tomio Onuki, Takeshi Okoshi, Toshikazu Tsumita, Taiyou Uehara, Takashi Sakamoto, Naoya Iwata, Hirohisa Kohno, Akihide Kawamura, Kazunori Koshimori
  • Publication number: 20080305442
    Abstract: A formation method for a patterned material layer comprising a step of exposing a composite layer to light in a predetermined pattern, the composite layer including a first photosensitive resin layer, a protective film, and an upper resin layer; a step of partly removing the exposed composite layer so as to form an opening exposing the substrate and form a groove along the main surface of the substrate on a side face of the opening by depressing the end portion of the upper resin layer on the substrate side, thereby forming a resist frame comprising the composite layer formed with the opening; a step of forming a vacuum coated layer having a material pattern part formed on the substrate in the opening and a part to lift off formed on the resist frame, by vacuum coating process; and a step of removing the part to lift off together with the resist frame, so as to yield a patterned material layer.
    Type: Application
    Filed: June 5, 2007
    Publication date: December 11, 2008
    Applicant: TDK CORPORATION
    Inventors: Kazuki Sato, Akifumi Kamijima, Takayasu Kanaya, Kei Hirata
  • Patent number: 7463449
    Abstract: A pole layer incorporate a track width defining and a wide portion. A material forming the pole layer is an alloy whose major elements are iron and nickel. In the alloy, where the proportions of iron and nickel with respect to the total of iron and nickel are indicated as (100?M) weight % and M weight %, respectively, M is greater than 0 and smaller than or equal to 10. The internal stress of the pole layer is a tensile stress. The magnetostriction constant of the material forming the pole layer is positive. Where the anisotropy field of the pole layer is Hk (A/m), the magnetostriction constant of the material forming the pole layer is ?(×10?6), and the internal stress of the pole layer is ? (MPa), the value of Hk/(?×?) is greater than 0.01 and smaller than 0.2.
    Type: Grant
    Filed: November 4, 2005
    Date of Patent: December 9, 2008
    Assignee: TDK Corporation
    Inventors: Kei Hirata, Atsushi Yamaguchi, Tetsuya Roppongi, Kiyoshi Noguchi
  • Publication number: 20080291582
    Abstract: Provided is a thin film magnetic head capable of suppressing an occurrence of a track erase, decreasing an influence on a magnetoresistive element caused by a magnetic flux generated from a thin film coil, and further decreasing the parasitic capacity. The thin film magnetic head has, in order in a stacked direction, a first magnetic shield layer, a magnetoresistive element, a second magnetic shield layer, a third magnetic shield layer, a main magnetic pole layer and a return yoke layer. A width in a track width direction of at least one of the first and the second magnetic shield layers is smaller than widths in a track width direction of the third magnetic shield layer and the return yoke layer.
    Type: Application
    Filed: May 21, 2007
    Publication date: November 27, 2008
    Applicant: TDK CORPORATION
    Inventors: Kei Hirata, Norikazu Ota, Yuichi Watabe, Tetsuro Sasaki, Takeo Kagami, Tetsuya Roppongi, Kazuki Sato, Yuji Otsubo, Sohei Horiuchi, Yoshiaki Tanaka, Kenji Yokoyama, Noriaki Kasahara
  • Publication number: 20080291579
    Abstract: A noise-testing method for a thin-film magnetic head with an MR read head element and a heating unit capable of applying a heat and a stress to the MR read head element, includes a step of applying alternately and discontinuously with each other an electrical power having a first level and an electrical power having a second level higher than the first level to the heating unit, and a step of evaluating the thin-film magnetic head by measuring a noise output or noise outputs obtained from the MR read head element when the electrical power or the electrical powers are applied to the heating unit.
    Type: Application
    Filed: May 25, 2007
    Publication date: November 27, 2008
    Applicants: TDK CORPORATION, SAE MAGNETICS (H.K.) LTD.
    Inventors: Takumi Uesugi, Takeo Kagami, Tetsuro Sasaki, Kei Hirata, Masaru Hirose, Chi Man Lee, Kwok Piu Tso
  • Publication number: 20080260430
    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: Application
    Filed: March 5, 2008
    Publication date: October 23, 2008
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Takashi Sakamoto, Kei Hirata, Akihide Kawamura, Naoya Iwata
  • Patent number: 7440238
    Abstract: The present invention provides a thin film magnetic head capable of satisfying both assurance of recording performance and assurance of reproduction performance. In the case where a lower magnetic layer is formed of an iron cobalt alloy (for example, Fe65Co35) which contains iron in a range of 60 at % to 80 at % and has extremely high saturation magnetic flux density of 2.4 T or higher, a head isolation layer formed of ruthenium (Ru) is provided between the lower magnetic layer and an upper read shield layer portion. As compared with the case where the head isolation layer is not provided between the lower magnetic layer and the upper read shield layer portion, the strength of a recording magnetic field increases and a reproduction output of an MR element is stabilized.
    Type: Grant
    Filed: April 25, 2006
    Date of Patent: October 21, 2008
    Assignee: TDK Corporation
    Inventors: Kei Hirata, Kiyoshi Noguchi, Atsushi Yamaguchi
  • Publication number: 20080226947
    Abstract: A magnetoresistance effect element includes a pinned layer having a fixed magnetization direction, a free layer having a magnetization direction variable depending on an external magnetic field, and a nonmagnetic spacer layer disposed between the pinned layer and the free layer. The free layer includes a Heusler alloy layer and a magnetostriction reduction layer made of a 4th group element, a 5th group element, or a 6th group element.
    Type: Application
    Filed: March 12, 2007
    Publication date: September 18, 2008
    Inventors: Tomohito MIZUNO, Yoshihiro TSUCHIYA, Kei HIRATA
  • Publication number: 20080226948
    Abstract: A magnetoresistance effect element (MR element) for use in a thin-film magnetic head has a buffer layer, an antiferromagnetic layer, a pinned layer, a spacer layer, a free layer, and a cap layer that are successively stacked. A sense current flows in a direction perpendicular to layer surfaces via a lower shield layer and an upper shield layer. The pinned layer comprises an outer layer having a fixed magnetization direction, a nonmagnetic intermediate layer, and an inner layer in the form of a ferromagnetic layer. The spacer layer comprises a first nonmagnetic metal layer, a semiconductor layer made of ZnO, and a second nonmagnetic metal layer. The inner layer or the outer layer includes a diffusion blocking layer made of an oxide of an element whose electronegativity is equal to or smaller than Zn, e.g., ZnO, TaO, ZrO, MgO, TiO, or HfO, or made of RuO.
    Type: Application
    Filed: March 12, 2007
    Publication date: September 18, 2008
    Inventors: Tomohito MIZUNO, Takahiko MACHITA, Kei HIRATA, Yoshihiro TSUCHIYA, Shinji HARA
  • Publication number: 20080218907
    Abstract: A magneto-resistance effect element (MR element) used for a thin film magnetic head is configured by a buffer layer, an anti-ferromagnetic layer, a pinned layer, a spacer layer, a free layer, and a cap layer, which are laminated in this order, and a sense current flows through the element in a direction orthogonal to the layer surface, via a lower shield layer and a upper shield layer. The pinned layer comprises an outer layer in which a magnetization direction is fixed, a non-magnetic intermediate layer, and an inner layer which is a ferromagnetic layer. The spacer layer comprises a first non-magnetic metal layer, a semiconductor layer, and a second non-magnetic metal layer. The first non-magnetic metal layer and the second non-magnetic metal layer comprise CuPt films having a thickness ranging from a minimum of 0.2 nm to a maximum of 2.0 nm, and the Pt content ranges from a minimum of 5 at % to a maximum of 25 at %.
    Type: Application
    Filed: March 6, 2007
    Publication date: September 11, 2008
    Applicant: TDK CORPORATION
    Inventors: Tomohito MIZUNO, Kei HIRATA, Yoshihiro TSUCHIYA, Koji SHIMAZAWA
  • Publication number: 20080218915
    Abstract: Provided is a TMR effect element having no special structures needing much man-hour cost for the formation, in which the high temperature noise and the low temperature noise are suppressed and a sufficiently high resistance-change ratio is provided. The TMR effect element comprises: a tunnel barrier layer formed by oxidizing a base film; and two ferromagnetic layers stacked so as to sandwich the tunnel barrier layer, the base film having a film thickness larger than a film thickness at which a resistance-change ratio of the TMR effect element indicates a maximum value. Here, in the case that the base film is an aluminum film, the film thickness of the aluminum film is preferably in the range of 0.50 nm to 1.5 nm.
    Type: Application
    Filed: March 5, 2007
    Publication date: September 11, 2008
    Applicant: TDK CORPORATION
    Inventors: Takumi Uesugi, Satoshi Miura, Tetsuro Sasaki, Takeo Kagami, Kei Hirata
  • Publication number: 20080218912
    Abstract: An MR element includes: a free layer whose direction of magnetization changes in response to a signal magnetic field; a pinned layer whose direction of magnetization is fixed; and a spacer layer disposed between these layers. The spacer layer includes: a semiconductor layer made of an n-type semiconductor; and a Schottky barrier forming layer made of a metal material having a work function higher than that of the n-type semiconductor that the semiconductor layer is made of, the Schottky barrier forming layer being disposed in at least one of a position between the semiconductor layer and the free layer and a position between the semiconductor layer and the pinned layer, touching the semiconductor layer and forming a Schottky barrier at an interface between the semiconductor layer and itself The semiconductor layer is 1.1 to 1.7 nm in thickness, and the Schottky barrier forming layer is 0.1 to 0.3 nm in thickness.
    Type: Application
    Filed: March 9, 2007
    Publication date: September 11, 2008
    Applicant: TDK CORPORATION
    Inventors: Kei Hirata, Satoshi Miura, Takeo Kagami, Tetsuro Sasaki
  • Publication number: 20080204938
    Abstract: Provided is a thin-film magnetic head in which a noise due to the voltage potential difference between the read head element and the protective coat surface is suppressed. The thin-film magnetic head comprises: a read head element, one end surface of the read head element reaching an head end surface on the ABS side; a protective coat formed on the head end surface in such a way to cover at least the one end surface of the read head element; and at least one antistatic means for preventing the protective coat from being electrostatically charged, formed on/above the element formation surface, one end surface of the at least one antistatic means reaching the head end surface, the protective coat covering a portion, not the whole, of the one end surface of the at least one antistatic means on the head end surface.
    Type: Application
    Filed: February 26, 2007
    Publication date: August 28, 2008
    Applicant: TDK Corporation
    Inventors: Kei Hirata, Takeo Kagami, Takumi Uesugi, Tetsuro Sasaki
  • Publication number: 20080174920
    Abstract: The invention provides a giant magneto-resistive effect device (CPP-GMR device) having a CPP (current perpendicular to plane) structure comprising a spacer layer, and a fixed magnetized layer and a free layer stacked one upon another with said spacer layer interleaved between them, with a sense current applied in a stacking direction, wherein the spacer layer comprises a first and a second nonmagnetic metal layer, each formed of a nonmagnetic metal material, and a semiconductor oxide layer interleaved between the first and the second nonmagnetic metal layer, wherein the semiconductor oxide layer that forms a part of the spacer layer is made of indium oxide (In2O3), or the semiconductor oxide layer contains indium oxide (In2O3) as its main component, and an oxide containing a tetravalent cation of SnO2 is contained in the indium oxide that is the main component.
    Type: Application
    Filed: January 24, 2007
    Publication date: July 24, 2008
    Applicant: TDK CORPORATION
    Inventors: Shinji Hara, Kei Hirata, Koji Shimazawa, Yoshihiro Tsuchiya, Tomohito Mizuno
  • Publication number: 20080170337
    Abstract: A TMR element includes a lower electrode layer, a TMR multi-layer stacked on the lower electrode layer, and an upper electrode layer stacked on the TMR multi-layer. The TMR multi-layer includes a tunnel barrier layer having a three-layered structure of a first crystalline layer, a crystalline semiconductor layer and a second crystalline insulation layer stacked in this order.
    Type: Application
    Filed: January 12, 2007
    Publication date: July 17, 2008
    Inventors: Kei Hirata, Satoshi Miura
  • Publication number: 20080170339
    Abstract: A magnetic head slider includes at least one thin-film magnetic head formed on a trailing surface of the magnetic head slider, and an ABS to be faced a magnetic disk in operation. At least a part of the ABS is made of a giant magnetostrictive material.
    Type: Application
    Filed: January 12, 2007
    Publication date: July 17, 2008
    Applicant: TDK CORPORATION
    Inventors: Naoki Ohta, Kei Hirata