Patents by Inventor Makoto Nagao

Makoto Nagao 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).

  • Publication number: 20040197606
    Abstract: A magnetic recording medium, which contains a chromium-containing primer layer and a magnetic layer at least on one surface of a nonmagnetic support member, the chromium-containing primer layer contains chromium and at least one type of element selected from a group of cobalt, beryllium, osmium, rhenium, titanium, zinc, tantalum, aluminum, molybdenum, tungsten, vanadium, iron, antimony, iridium, ruthenium, rhodium, platinum, palladium, silicon, and zirconium, and the magnetic layer contains a ferromagnetic metal alloy containing at least cobalt, platinum and chromium, and a nonmagnetic material.
    Type: Application
    Filed: April 19, 2004
    Publication date: October 7, 2004
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Kazuyuki Usuki, Kenichi Moriwaki, Kazutoshi Katayama, Makoto Nagao
  • Patent number: 6794062
    Abstract: In the performance of a magnetic transfer utilizing a magnetic transfer master medium, the occurrence of signal omissions in the magnetic data transferred to the slave medium is prevented. By forming the protrusion portions of the uneven pattern formed on the surface of the master medium so that the width thereof in the direction of the track pitch is narrower than said track width, no depression portions that are surrounded on all four sides by protrusion portions are formed.
    Type: Grant
    Filed: January 22, 2002
    Date of Patent: September 21, 2004
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hisashi Tsubata, Makoto Nagao
  • Patent number: 6759183
    Abstract: A master medium for use in magnetic transfer of information includes a metal disk which has a first relief or recess pattern representing the information. The metal disk is produced by exposing a photoresist film formed on a base disk with a laser or electron beam modulated with the information while rotating the base disk; developing the photoresist film so as to form an original disk having a second relief or recess pattern; depositing metal on the original disk so as to mold the metal disk on the original disk; and removing the metal disk from the original disk.
    Type: Grant
    Filed: April 30, 2003
    Date of Patent: July 6, 2004
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Makoto Nagao, Seiichi Watanabe, Masakazu Nishikawa
  • Patent number: 6735026
    Abstract: Disclosed is a magnetic transfer method magnetically transferring information signals such as servo signals from a master medium to a slave medium, which is capable of preventing the occurrence of missing signals due to insufficient contact of the master medium and the slave medium originating from adhering of dust to the slave medium, thus increasing reliability. When the master medium bearing information signals and the slave medium are brought into close contacted with each other, and when a transfer magnetic field is applied to the master medium and the slave medium to magnetically transfer the information signal from the master medium to the slave medium, a metal thin film formed on a substrate of the master medium is electrically grounded, and charges of the master medium are removed, thus reducing a quantity of adhering dust.
    Type: Grant
    Filed: August 3, 2001
    Date of Patent: May 11, 2004
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Masakazu Nishikawa, Makoto Nagao
  • Patent number: 6731440
    Abstract: The present invention provides a method for magnetic transfer, the method including the steps of arranging ring shape head electromagnets at least on one of upper and lower surfaces of the slave medium, rotating the slave medium or the ring shape head electromagnet in track direction, performing initial DC magnetization on the slave medium in advance in track direction by applying magnetic field in track direction on the surface of the slave medium, bringing the master carrier for magnetic transfer closely together with the slave medium processed by the initial DC magnetization, and performing magnetic transfer by applying magnetic field for transfer in track direction reverse to the direction of the initial DC magnetization on the surface of the slave medium.
    Type: Grant
    Filed: May 5, 2000
    Date of Patent: May 4, 2004
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kazunori Komatsu, Makoto Nagao, Masakazu Nishikawa
  • Publication number: 20040043256
    Abstract: In the performance of a magnetic transfer utilizing a magnetic transfer master medium, the occurrence of signal omissions in the magnetic data transferred to the slave medium is prevented. By forming the protrusion portions of the uneven pattern formed on the surface of the master medium so that the width thereof in the direction of the track pitch is narrower than said track width, no depression portions that are surrounded on all four sides by protrusion portions are formed.
    Type: Application
    Filed: August 29, 2003
    Publication date: March 4, 2004
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Hisashi Tsubata, Makoto Nagao
  • Publication number: 20040038077
    Abstract: A master carrier for magnetic transfer used in a transfer method for applying a magnetic field for transfer by bringing a master carrier for magnetic transfer into close contact with a slave medium, the master carrier having a magnetic layer corresponding to a recording information for transfer formed on surface of a substrate, the slave medium serving as a magnetic recording medium where the information is to be transferred, whereby relative permeability of the magnetic layer of the master carrier for magnetic transfer is within the range of 10-1000.
    Type: Application
    Filed: July 28, 2003
    Publication date: February 26, 2004
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Makoto Nagao, Ryuji Sugita, Masakazu Nishikawa
  • Patent number: 6643079
    Abstract: The present invention provides a method for magnetic transfer, said method comprising the steps of arranging permanent magnets each having magnetic field symmetrical to the axis of the magnetic pole at least on one of upper or lower surfaces of the slave medium with the axis of the magnetic pole disposed in parallel to the surface of the slave medium, rotating the slave medium or the permanent magnet in track direction, performing initial DC magnetization on the slave medium in advance in track direction, bringing the master carrier for magnetic transfer closely together with the slave medium processed by said initial DC magnetization, and performing magnetic transfer by applying magnetic field for transfer in track direction reverse to the direction of the initial DC magnetization on the surface of the slave medium.
    Type: Grant
    Filed: April 26, 2000
    Date of Patent: November 4, 2003
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kazunori Komatsu, Makoto Nagao, Masakazu Nishikawa
  • Publication number: 20030198833
    Abstract: A master medium for use in magnetic transfer of information includes a metal disk which has a first relief or recess pattern representing the information. The metal disk is produced by exposing a photoresist film formed on a base disk with a laser or electron beam modulated with the information while rotating the base disk; developing the photoresist film so as to form an original disk having a second relief or recess pattern; depositing metal on the original disk so as to mold the metal disk on the original disk; and removing the metal disk from the original disk.
    Type: Application
    Filed: April 30, 2003
    Publication date: October 23, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Makoto Nagao, Seiichi Watanabe, Masakazu Nishikawa
  • Patent number: 6636371
    Abstract: The invention provides a magnetic transfer method in which a magnetic transfer master carrier having a magnetic layer at a surface portion of a substrate having an information signal is brought in contact with a magnetic recording medium that is an associated slave medium and a transfer magnetic field is applied to the slave medium. The coercive force Hcs of the slave magnetic recording medium and the transfer magnetic field satisfies the relation: 0.6×Hcs≦transfer magnetic field≦1.
    Type: Grant
    Filed: April 26, 2000
    Date of Patent: October 21, 2003
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kazunori Komatsu, Makoto Nagao, Masakazu Nishikawa
  • Patent number: 6602301
    Abstract: The present invention provides a method for magnetic transfer, the method including the steps of arranging a pair of permanent magnets each having magnetic field symmetrical to the axis of the magnetic pole and with the same polarities facing to each other with the axis of the magnetic pole running perpendicularly to the surface of the slave medium, and arranging two pairs of said permanent magnets at adjacent positions so that the adjacent magnets have the poles with opposite polarities adjacent to each other, rotating the slave medium or the two pairs of permanent magnets in track direction, and applying magnetic field in track direction on the surface of the slave medium, performing initial DC magnetization on the slave medium in advance in track direction, bringing the master carrier for magnetic transfer and the slave medium processed by said initial DC magnetization closely together, and performing magnetic transfer by applying magnetic field for transfer in a direction reverse to the direction of the i
    Type: Grant
    Filed: April 26, 2000
    Date of Patent: August 5, 2003
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kazunori Komatsu, Makoto Nagao, Masakazu Nishikawa
  • Publication number: 20030134151
    Abstract: The present invention provides a magnetic recording medium, which comprises a chromium-containing primer layer and a magnetic layer at least on one surface of a nonmagnetic support member, said chromium-containing primer layer contains chromium and at least one type of element selected from a group of cobalt, beryllium, osmium, rhenium, titanium, zinc, tantalum, aluminum, molybdenum, tungsten, vanadium, iron, antimony, iridium, ruthenium, rhodium, platinum, palladium, silicon, and zirconium, and said magnetic layer comprises a ferromagnetic metal alloy containing at least cobalt, platinum and chromium, and a nonmagnetic material.
    Type: Application
    Filed: September 11, 2002
    Publication date: July 17, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Kazuyuki Usuki, Kenichi Moriwaki, Kazutoshi Katayama, Makoto Nagao
  • Patent number: 6577459
    Abstract: The present invention provides a method for magnetic transfer and an apparatus for magnetic transfer, by which it is possible to transfer a transfer pattern with high quality from a master carrier for magnetic transfer to a slave medium by magnetic transfer regardless of position of the magnetic pattern. The method and the apparatus for magnetic transfer according to the present invention are used to apply magnetic field for transfer by bringing the master carrier for magnetic transfer into contact with the slave medium, the master carrier having a magnetic layer formed on a portion corresponding to an information signal on surface of a substrate, and the slave medium being a magnetic recording medium for receiving magnetic transfer after performing initial DC magnetization by a magnetic field by more than 1.
    Type: Grant
    Filed: June 12, 2000
    Date of Patent: June 10, 2003
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kazunori Komatsu, Makoto Nagao, Masakazu Nishikawa
  • Patent number: 6570724
    Abstract: The present invention provides a method for magnetic transfer, which including the steps of: arranging permanent magnets each magnetized symmetrically to the axis of the magnetic pole with the same polarities facing to each other and with the slave medium interposed between, and disposing the slave medium perpendicularly to the axis of the magnetic pole, rotating the slave medium or the permanent magnets in track direction; and applying magnetic field in track direction on the surface of the slave medium, whereby: after initial DC magnetization has been formed on the slave medium in advance in track direction, the master carrier for magnetic transfer and the slave medium processed by the initial DC magnetization are brought closely together, and a magnetic field for transfer in reverse direction to the direction of the initial DC magnetization on the surface of the slave medium is applied in track direction, and magnetic transfer is performed.
    Type: Grant
    Filed: April 26, 2000
    Date of Patent: May 27, 2003
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kazunori Komatsu, Makoto Nagao, Masakazu Nishikawa
  • Publication number: 20030076611
    Abstract: In an information recording method of the present invention by carrying out recording data while carrying out tracking servo accurately, high density recording of signals at a good S/N can be carried out, and high density recording by a vertical magnetic recording system can be carried out. A magnetic disk comprises a magnetic recording layer, and the magnetic recording layer is magnetized in advance such that magnetized regions A and B having different magnetization directions are formed. At a time of recording data, vertical magnetic recording is carried out by a magnetic head while carrying out accurate tracking servo by optically tracking by a magneto-optical effect utilizing a difference in the magnetization directions of the magnetized regions A and B. Therefore, high-density recording at a good S/N is possible.
    Type: Application
    Filed: October 4, 2002
    Publication date: April 24, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Kazuyuki Usuki, Masakazu Nishikawa, Makoto Nagao
  • Publication number: 20030002182
    Abstract: A magnetic transfer device for bringing a master carrier with information and a slave medium into intimate contact with each other and then applying a transfer field to transfer the information to the slave medium. The master carrier has an inclined face on its radially outer end. After the magnetic transfer of the information, claws are inserted in the gas formed by the inclined face of the master carrier and the slave medium. The slave medium held in intimate contact with the master carrier is separated from the master carrier by lifting the slave medium with the claws.
    Type: Application
    Filed: May 14, 2002
    Publication date: January 2, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Akito Kamatani, Masakazu Nishikawa, Makoto Nagao, Kazunori Komatsu, Tsuneo Inui, Kazuhiro Niitsuma
  • Publication number: 20020141088
    Abstract: In the magnetic transferring method for magnetically transferring an information signal such as a servo signal from the master medium to the slave medium, when magnetic transfer is performed by bringing a master medium and a slave medium into close contact with each other, the master medium bearing an information signal and the slave medium having a lubricating layer formed on the surface of its recording plane during use, and applying a transfer magnetic field, the magnetic transfer is performed by bringing the slave medium before the formation of the lubricating layer and the master medium into close contact with each other. Thus, the separation of the slave medium from the master medium after the magnetic transfer is facilitated and the adsorption of dust on the slave medium is prevented.
    Type: Application
    Filed: February 8, 2002
    Publication date: October 3, 2002
    Applicant: Fuji Photo Film Co., Ltd
    Inventors: Masakazu Nishikawa, Makoto Nagao
  • Patent number: 6433944
    Abstract: The present invention provides a master carrier for magnetic transfer, comprising a plurality of transfer information recording sectors having recording information magnetized thereon, a non-magnetic-material sector defining each of the transfer information recording sectors is present between each of adjacent transfer information recording sectors, and surfaces of the transfer information recording sectors and surfaces of the non-magnetic material sectors are positioned on and form the same plane.
    Type: Grant
    Filed: September 22, 1999
    Date of Patent: August 13, 2002
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Makoto Nagao, Kazutoshi Katayama, Ryuji Sugita
  • Publication number: 20020098387
    Abstract: In the performance of a magnetic transfer utilizing a magnetic transfer master medium, the occurrence of signal omissions in the magnetic data transferred to the slave medium is prevented. By forming the protrusion portions of the uneven pattern formed on the surface of the master medium so that the width thereof in the direction of the track pitch is narrower than said track width, no depression portions that are surrounded on all four sides by protrusion portions are formed.
    Type: Application
    Filed: January 22, 2002
    Publication date: July 25, 2002
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Hisashi Tsubata, Makoto Nagao
  • Publication number: 20020081461
    Abstract: There are provided an information recording medium which permits accurate tracking servo, and a method for recording and reproducing for an information recording medium which allows recording and reproducing of a signal at a favorable S/N by carrying out at least one of information recording and information reproduction while accurately performing tracking servo. A magneto-optic disk includes a magnetic recording layer for magnetically recording information. The magnetic recording layer is in advance magnetized for concentrically or spirally around the center of the disk in such a manner that magnetized regions are disposed such that adjacent regions are magnetized in different directions and alternately arranged in the radial direction of the disk. Accordingly, tracking can be continuously performed and accurate tracking servo can also be performed.
    Type: Application
    Filed: December 21, 2001
    Publication date: June 27, 2002
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Masakazu Nishikawa, Kazuyuki Usuki, Yoshihisa Usami, Makoto Nagao