Patents by Inventor Hiroaki Nemoto

Hiroaki Nemoto 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: 6773826
    Abstract: A perpendicular magnetic recording medium and a magnetic storage apparatus, which show an excellent S/N ratio and are suitable for ultra high density magnetic recording, are provided. In the perpendicular magnetic recording medium having a recording layer composed of at least two layers of a main recording layer formed above a substrate and a thermally-stabilizing layer formed on the main recording layer, the thermally-stabilizing layer being formed closer to a surface of the medium than the main recording layer, alloy containing Co and Cr as a main component, which shows a low noise property, is used as the main recording layer, amorphous alloy containing rare earth metals and 3d transition metals as a main component, which is excellent in thermal stability, is used as the thermally-stabilizing layer, and a cap layer formed of alloy containing Co and Cr as a main component is formed on a surface of the thermally-stabilizing layer.
    Type: Grant
    Filed: February 19, 2002
    Date of Patent: August 10, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Hiroyuki Nakagawa, Hiroaki Nemoto, Yuzuru Hosoe
  • Publication number: 20040146747
    Abstract: Co/Pd or Co/Pt superlattice is provided to enable magnetic recording devices to sustain good recording/readback performances across a wide range of temperatures. Such a superlattice medium includes a substrate and a magnetic layer formed on the substrate and the magnetic layer comprises multilayer superlattice films of ferromagnetic metal layers which contain Co and paramagnetic metal layers which consist of Pd and/or Pt, wherein the ferromagnetic metal layers further contain a paramagnetic element and the thickness of the paramagnetic metal layers is 0.8 nm or less. When a magnetic torque loop of the perpendicular magnetic recording medium is measured with a torque magnetometer, the polarity of a value of loop components with translational symmetry of 90 degrees should be opposite to the polarity of a value of loop components with translational symmetry of 180 degrees.
    Type: Application
    Filed: July 10, 2003
    Publication date: July 29, 2004
    Applicant: Hitachi, Ltd.
    Inventors: Hiroaki Nemoto, Ikuko Takekuma, Yuzuru Hosoe, Hiroyuki Nakagawa, Masukazu Igarashi
  • Publication number: 20040064934
    Abstract: Magnetic heads capable of recording and reading with high sensitivity and resolution are provided by minimizing the outflow of magnetic fluxes from a flux guide to magnetic shields while using a flux guide structure for an MR element. In the magnetic head, magnetic shields exposed on a surface opposite a magnetic recording medium (air bearing surface) and a flux guide exposed between the magnetic heads via a non-magnetic layer are provided, and magnetic heads via a non-magnetic layer are provided, and magnetic fluxes are guided by the flux guide to a magnetoresistive (MR) element formed in a position not exposed on the air bearing surface. The height of the magnetic shields in a direction perpendicular to the air bearing surface is less than the distance from the air bearing surface to the MR element, and the lengthwise direction of the magnetic shields is in parallel to the air bearing surface in the vicinity of the position in which the flux guide is formed.
    Type: Application
    Filed: October 7, 2003
    Publication date: April 8, 2004
    Applicant: Hitachi, Ltd.
    Inventor: Hiroaki Nemoto
  • Publication number: 20040038083
    Abstract: A perpendicular magnetic recording medium includes an intermediate film formed of a plurality of layers between a soft magnetic film and a perpendicular magnetization film. The intermediate film includes at least two layers, i.e., an oxygen-containing layer, or a nonmetallic element-containing layer containing nitrogen, silicon or carbon, and a metallic layer formed on a surface side of the oxygen-containing layer or the nonmetallic element-containing layer. The metallic layer includes a plurality of isolated island-shaped structures. Crystal grains of the perpendicular magnetization film are formed so as to correspond to the isolated island-shaped structures. As a result, a high recording density is obtained.
    Type: Application
    Filed: February 25, 2003
    Publication date: February 26, 2004
    Applicant: Hitachi, Ltd.
    Inventors: Yoshiyuki Hirayama, Hiroyuki Nakagawa, Hiroaki Nemoto, Ichiro Tamai, Ikuko Takekuma
  • Patent number: 6683823
    Abstract: A method for reproducing information on a recording medium includes irradiating electromagnetic energy or light to the recording medium from one side with respect to the recording medium, applying a recording magnetic field to an electromagnetic energy or light irradiated position on the recording medium from the one side of irradiating electromagnetic energy or light, and detecting magnetic leakage flux emerging from the recording medium from the one side of irradiating electromagnetic energy or light.
    Type: Grant
    Filed: December 17, 2002
    Date of Patent: January 27, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Hideki Saga, Hiroaki Nemoto, Hirofumi Sukeda, Masahiko Takahashi, Kimio Nakamura, Yohji Maruyama, Hiroshi Ide, Takehiko Hamaguchi
  • Patent number: 6665152
    Abstract: Magnetic heads capable of recording and reading with high sensitivity and resolution are provided by minimizing the outflow of magnetic fluxes from a flux guide to magnetic shields while using a flux guide structure for an MR element. In the magnetic head, magnetic shields exposed on a surface opposite a magnetic recording medium (air bearing surface) and a flux guide exposed between the magnetic heads via a non-magnetic layer are provided, and magnetic fluxes are guided by the flux guide to a magnetoresistive (MR) element formed in a position not exposed on the air bearing surface. The height of the magnetic shields in a direction perpendicular to the air bearing surface is less than the distance from the air bearing surface to the MR element, and the lengthwise direction of the magnetic shields is in parallel to the air bearing surface in the vicinity of the position in which the flux guide is formed.
    Type: Grant
    Filed: August 3, 2001
    Date of Patent: December 16, 2003
    Assignee: Hitachi, Ltd.
    Inventor: Hiroaki Nemoto
  • Publication number: 20030162041
    Abstract: A perpendicular magnetic recording medium, which has a low level of recording noise and sufficiently large perpendicular magnetic anisotropy energy relative to demagnetizing field energy, includes a substrate and a multi-layered magnetic film. The multi-layered magnetic film is composed of ferromagnetic metal layers of Co alloy containing at least Cr and non-magnetic metal layers of Pd alloy, each one layer of which are laminated alternately on top of one layer of the other. The ferromagnetic metal layers and the non-magnetic metal layers have a thickness of d1 and d2, respectively, with the ratio of d1/d2 being in the range of 1.5 to 4.0. This specific layer structure reduces the magnetic exchange interaction between magnetic particles in the multi-layered magnetic film. Therefore, the perpendicular magnetic recording medium is stable against thermal disturbance and has a low level of recording noise.
    Type: Application
    Filed: August 14, 2002
    Publication date: August 28, 2003
    Inventors: Hiroaki Nemoto, Hiroyuki Nakagawa, Yuzuru Hosoe
  • Publication number: 20030123333
    Abstract: A method for reproducing information on a recording medium includes irradiating electromagnetic energy or light to the recording medium from one side with respect to the recording medium, applying a recording magnetic field to an electromagnetic energy or light irradiated position on the recording medium from the one side of irradiating electromagnetic energy or light, and detecting magnetic leakage flux emerging from the recording medium from the one side of irradiating electromagnetic energy or light.
    Type: Application
    Filed: December 17, 2002
    Publication date: July 3, 2003
    Inventors: Hideki Saga, Hiroaki Nemoto, Hirofumi Sukeda, Masahiko Takahashi, Kimio Nakamura, Yohji Maruyama, Hiroshi Ide, Takehiko Hamaguchi
  • Patent number: 6572963
    Abstract: A process for forming an inorganic material layer pattern on a substrate. The process includes the steps of transferring an inorganic powder dispersed paste layer supported on a support film to the surface of the substrate to form the inorganic powder dispersed paste layer on the substrate; forming a resist film on the inorganic powder dispersed paste layer transferred to the surface of the substrate; exposing the resist film to light through a mask to form a latent image of a resist pattern; developing the exposed resist film to form the resist pattern; etching exposed portions of the inorganic powder dispersed paste layer to form an inorganic powder dispersed paste layer pattern corresponding to the resist pattern; and baking the pattern to form an inorganic material layer pattern.
    Type: Grant
    Filed: October 17, 2001
    Date of Patent: June 3, 2003
    Assignee: JSR Corporation
    Inventors: Hideaki Masuko, Tadahiko Udagawa, Hiroaki Nemoto, Nobuo Bessho
  • Patent number: 6560168
    Abstract: An information recording apparatus using a recording medium which holds information by reversed magnetic domains on a perpendicular magnetic recording film includes an irradiation unit for applying electromagnetic energy or light onto the recording medium, and a magnetic flux detection unit for detecting magnetic leakage flux emerging from the recording medium, the magnetic flux detection unit being disposed on the same side as the irradiation unit with respect to the recording medium. As a result, both side recording of the recording medium can be conducted.
    Type: Grant
    Filed: December 12, 2000
    Date of Patent: May 6, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Hideki Saga, Hiroaki Nemoto, Hirofumi Sukeda, Masahiko Takahashi, Kimio Nakamura, Yohji Maruyama, Hiroshi Ide, Takehiko Hamaguchi
  • Publication number: 20030059650
    Abstract: A perpendicular magnetic recording medium and a magnetic storage apparatus, which show an excellent S/N ratio and are suitable for ultra high density magnetic recording, are provided. In the perpendicular magnetic recording medium having a recording layer composed of at least two layers of a main recording layer formed above a substrate and a thermally-stabilizing layer formed on the main recording layer, the thermally-stabilizing layer being formed closer to a surface of the medium than the main recording layer, alloy containing Co and Cr as a main component, which shows a low noise property, is used as the main recording layer, amorphous alloy containing rare earth metals and 3d transition metals as a main component, which is excellent in thermal stability, is used as the thermally-stabilizing layer, and a cap layer formed of alloy containing Co and Cr as a main component is formed on a surface of the thermally-stabilizing layer.
    Type: Application
    Filed: February 19, 2002
    Publication date: March 27, 2003
    Inventors: Hiroyuki Nakagawa, Hiroaki Nemoto, Yuzuru Hosoe
  • Publication number: 20030049412
    Abstract: A process for forming an inorganic material layer pattern on a substrate. The process includes the steps of transferring an inorganic powder dispersed paste layer supported on a support film to the surface of the substrate to form the inorganic powder dispersed paste layer on the substrate; forming a resist film on the inorganic powder dispersed paste layer transferred to the surface of the substrate; exposing the resist film to light through a mask to form a latent image of a resist pattern; developing the exposed resist film to form the resist pattern; etching exposed portions of the inorganic powder dispersed paste layer to form an inorganic powder dispersed paste layer pattern corresponding to the resist pattern; and baking the pattern to form an inorganic material layer pattern.
    Type: Application
    Filed: October 23, 2002
    Publication date: March 13, 2003
    Applicant: JSR CORPORATION
    Inventors: Hideaki Masuko, Tadahiko Udagawa, Hiroaki Nemoto, Nobuo Bessho
  • Publication number: 20020141118
    Abstract: Magnetic heads capable of recording and reading with high sensitivity and resolution are provided by minimizing the outflow of magnetic fluxes from a flux guide to magnetic shields while using a flux guide structure for an MR element. In the magnetic head, magnetic shields exposed on a surface opposite a magnetic recording medium (air bearing surface) and a flux guide exposed between the magnetic heads via a non-magnetic layer are provided, and magnetic fluxes are guided by the flux guide to a magnetoresistive (MR) element formed in a position not exposed on the air bearing surface. The height of the magnetic shields in a direction perpendicular to the air bearing surface is less than the distance from the air bearing surface to the MR element, and the lengthwise direction of the magnetic shields is in parallel to the air bearing surface in the vicinity of the position in which the flux guide is formed.
    Type: Application
    Filed: August 3, 2001
    Publication date: October 3, 2002
    Applicant: Hitachi, Ltd.
    Inventor: Hiroaki Nemoto
  • Patent number: 6368774
    Abstract: A radiation sensitive composition comprising (A), a mixture of an isoindolinone pigment and a yellow organic pigment, (B) an alkali-soluble resin, (C) a polyfunctional monomer and (D) a photopolymerization initiator. The composition is useful for production of an additive or subtractive color filter which is used in a reflection-type color liquid crystal display device.
    Type: Grant
    Filed: June 2, 2000
    Date of Patent: April 9, 2002
    Assignee: JSR Corporation
    Inventors: Kouichi Sakurai, Hiroaki Nemoto, Atsushi Kumano
  • Publication number: 20020034611
    Abstract: A process for forming an inorganic material layer pattern on a substrate. The process includes the steps of transferring an inorganic powder dispersed paste layer supported on a support film to the surface of the substrate to form the inorganic powder dispersed paste layer on the substrate; forming a resist film on the inorganic powder dispersed paste layer transferred to the surface of the substrate; exposing the resist film to light through a mask to form a latent image of a resist pattern; developing the exposed resist film to form the resist pattern; etching exposed portions of the inorganic powder dispersed paste layer to form an inorganic powder dispersed paste layer pattern corresponding to the resist pattern; and baking the pattern to form an inorganic material layer pattern.
    Type: Application
    Filed: October 17, 2001
    Publication date: March 21, 2002
    Applicant: JSR CORPORATION, A JAPANESE CORPORATION
    Inventors: Hideaki Masuko, Tadahiko Udagawa, Hiroaki Nemoto, Nobuo Bessho
  • Patent number: 6348298
    Abstract: A radiation sensitive composition comprising (A) a colorant containing a quinacridone pigment, a mixture of an isoindolinone pigment and a yellow organic pigment or a mixture of copper phthalocyanine blue and a green pigment, (B) an alkali-soluble resin, (C) a polyfunctional monomer and (D) a photopolymerization initiator. The composition is useful for production of an additive or subtractive color filter which is used in a reflection-type color liquid crystal display device.
    Type: Grant
    Filed: June 2, 2000
    Date of Patent: February 19, 2002
    Assignee: JSR Corporation
    Inventors: Kouichi Sakurai, Hiroaki Nemoto, Atsushi Kumano
  • Patent number: 6337028
    Abstract: A process for forming an inorganic material layer pattern on a substrate. The process includes the steps of transferring an inorganic powder dispersed paste layer supported on a support film to the surface of the substrate to form the inorganic powder dispersed paste layer on the substrate; forming a resist film on the inorganic powder dispersed paste layer transferred to the surface of the substrate; exposing the resist film to light through a mask to form a latent image of a resist pattern; developing the exposed resist film to form the resist pattern; etching exposed portions of the inorganic powder dispersed paste layer to form an inorganic powder dispersed paste layer pattern corresponding to the resist pattern; and baking the pattern to form an inorganic material layer pattern.
    Type: Grant
    Filed: November 10, 1998
    Date of Patent: January 8, 2002
    Assignee: JSR Corporation
    Inventors: Hideaki Masuko, Tadahiko Udagawa, Hiroaki Nemoto, Nobuo Bessho
  • Patent number: 6299785
    Abstract: A process for the preparation of an electrode, which comprises: (1) transferring a conductive paste layer supported on a base film to a substrate to form the conductive paste layer on the substrate; (2) forming a resist film on the conductive paste layer transferred to the substrate; (3) exposing the resist film through a mask to form a resist pattern latent image; (4) developing the exposed resist film to form a resist pattern; (5) etching exposed portions of the conductive paste layer to form a conductive paste layer pattern corresponding to the resist pattern; and (6) thermosetting the pattern to form a conductive layer pattern.
    Type: Grant
    Filed: April 22, 1999
    Date of Patent: October 9, 2001
    Assignee: JSR Corporation
    Inventors: Tsutomu Shimokawa, Hideaki Masuko, Hiroaki Nemoto, Nobuo Bessho
  • Patent number: 6288981
    Abstract: In an optical recording and magnetic-head reproducing system, the reproduced output is prevented from starting to decrease, upon the length of record bits getting shorter, in the range of the bit length larger than reproducing resolution of a magnetic reproducing head. When data are recorded magneto-optically on a magnetic recording medium, the radius of curvature of arcs constituting the boundary of recorded magnetic domains is made as large as possible so that the shape of the recorded spot may be substantially rectangular. As a result, it becomes possible to improve the efficiency of magnetic reproduction, and high-output as well as high-SN-ratio reproduction at high linear recording density can be achieved.
    Type: Grant
    Filed: July 18, 2000
    Date of Patent: September 11, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Kazuetsu Yoshida, Hiroaki Nemoto, Hideki Saga
  • Patent number: 6255034
    Abstract: A radiation sensitive composition contains (A) a colorant, (B) a binder polymer, (C) a polyfunctional monomer and (D) a carboxyl group-containing monofunctional monomer, an amide group-containing monoethylenically unsaturated monomer, a monoethylenically unsaturated monomer having a cyclic amide group or cyclic imide group or a phenyl group-containing (meth)acrylate, and (E) a photopolymerization initiator. The composition is useful for producing a color filter for use in color liquid crystal display device, color image pick-up elements etc.
    Type: Grant
    Filed: September 8, 1998
    Date of Patent: July 3, 2001
    Assignee: JSR Corporation
    Inventors: Satoshi Shimada, Tomio Nagatsuka, Hiroaki Nemoto, Atsushi Kumano