Patents by Inventor Kazuhiro Niitsuma

Kazuhiro Niitsuma 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: 20030113583
    Abstract: A master information carrier for magnetic transfer includes a base sheet which is formed of a magnetic material. The master information carrier is provided with an irregularity pattern representing information to be transferred to a magnetic recording medium and a magnetic layer formed along the irregularity pattern.
    Type: Application
    Filed: December 12, 2002
    Publication date: June 19, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Masakazu Nishikawa, Kazuhiro Niitsuma, Tadashi Yasunaga, Toshihiro Usa, Kazunori Komatsu
  • Publication number: 20030112558
    Abstract: A magnetic disk cartridge comprising a housing with space, and a magnetic disk rotatably held in the space of the housing. The magnetic disk includes a flexible magnetic recording medium, and at least one rigid ring mounted on the circumferential edge portion of the magnetic recording medium.
    Type: Application
    Filed: December 10, 2002
    Publication date: June 19, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventor: Kazuhiro Niitsuma
  • Publication number: 20030099803
    Abstract: A magnetic recording medium comprising a card-type disk drive and a magnetic disk cartridge. The card-type disk drive is loaded in a card slot of electronic equipment. The magnetic disk cartridge has a magnetic disk rotatably supported within a housing, and is inserted into and ejected from the disk drive through a cartridge-inserting slot. The magnetic disk cartridge includes an ejection manipulation member that has a push manipulation portion and a leading end portion. The leading end portion protrudes from the front wall of the housing when the push manipulation portion is pushed in a cartridge-inserting direction. The disk drive has cartridge ejection means for moving the magnetic disk cartridge in a cartridge-ejecting direction when the leading end portion of the ejection manipulation member protrudes from the front wall of the housing.
    Type: Application
    Filed: November 26, 2002
    Publication date: May 29, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventor: Kazuhiro Niitsuma
  • Publication number: 20030099867
    Abstract: A master information carrier for magnetic transfer to an in-plane magnetic recording medium includes a base sheet having an irregularity pattern representing information to be transferred to an in-plane magnetic recording medium and a magnetic layer formed along the irregularity pattern.
    Type: Application
    Filed: November 27, 2002
    Publication date: May 29, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Masakazu Nishikawa, Kazuhiro Niitsuma, Tadashi Yasunaga, Toshihiro Usa, Kazunori Komatsu
  • Publication number: 20030067715
    Abstract: A magnetic disk cartridge for use in a disk drive having both a slot and a guide portion. The magnetic disk cartridge comprises a generally disk-shaped housing in which a magnetic disk is rotatably housed, and protrusions. The protrusions are formed on the main surface of the housing and are used for positioning the magnetic disk cartridge in a direction capable of recording and reproduction in cooperation with the guide portion of the disk drive when the magnetic disk cartridge is loaded in the disk drive.
    Type: Application
    Filed: October 9, 2002
    Publication date: April 10, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Kazuhiro Niitsuma, Ryosuke Ogura, Kazuo Hiraguchi
  • Publication number: 20030063403
    Abstract: A master carrier for magnetic transfer is equipped with a substrate having a land/groove pattern. The land/groove pattern is formed from a magnetic material and corresponds to information that is transferred to a magnetic recording disk. Each land in the land/groove pattern has four round corners whose radius is from 1% through 47% of the width of a data track on the disk.
    Type: Application
    Filed: May 13, 2002
    Publication date: April 3, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Masakazu Nishikawa, Tadashi Yasunaga, Kazuhiro Niitsuma
  • Publication number: 20030048557
    Abstract: The present invention enables to execute accurate magnetic transfer without signal omission and the like, by bringing a master carrier which bore transfer information and a slave medium to undergo transfer into close contact with each other uniformly and without a gap when they are received in a holder and brought into confronted close contact with each other.
    Type: Application
    Filed: June 21, 2002
    Publication date: March 13, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Masakazu Nishikawa, Kazuhiro Niitsuma
  • Publication number: 20030030927
    Abstract: By bring a master carrier and a slave medium into close contact with uniform force when executing magnetic transfer by applying transfer magnetic field in the state that the master carrier and slave medium is in confronted close contact and received within a holder, inferiority of transfer such as omission of signals is prevented and quality of transfer signals is enhanced.
    Type: Application
    Filed: June 13, 2002
    Publication date: February 13, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Masakazu Nishikawa, Kazuhiro Niitsuma, Akito Kamatani
  • Publication number: 20030017287
    Abstract: A disk container for accommodating a disk recording medium in the present invention comprises specified material having an antifungal function.
    Type: Application
    Filed: June 19, 2002
    Publication date: January 23, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Kazuhiro Niitsuma, Shinichi Kato
  • 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
  • Patent number: 5773137
    Abstract: A magnetic recording disk having a flexible non-magnetic support, an intervening non-magnetic layer of 0.5 to 5 .mu.m thick which contains as binder and anon-magnetic inorganic powder, and a magnetic layer of 0.02 to 0.5 .mu.m thick containing a binder, a ferromagnetic powder, carbon black and a lubricant to reduced in its tendency to make a magnetic head of a magnetic recording/reproducing device corrosive without reducing its running endurance, by employing a binder polymer containing no chlorine atom in its molecular structure for both the non-magnetic layer and the magnetic layer and by making the magnetic layer to have an upper surface having a Knoop hardness of 14 to 25.
    Type: Grant
    Filed: June 21, 1996
    Date of Patent: June 30, 1998
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kazuhiro Niitsuma, Yasushi Endo
  • Patent number: 5455093
    Abstract: A flexible magnetic disk is disclosed, which comprises a non-magnetic support having thereon a non-magnetic layer comprising mainly a non-magnetic powder and a binder resin, and a magnetic layer comprising mainly a ferromagnetic layer and a binder resin, in this order, wherein at least a part of the non-magnetic powder in the non-magnetic layer is an electrically conductive powder, and therein the product Et.sup.3 of Young's modulus (E) of the flexible magnetic disk and the cube of the thickness (t) thereof is 50 to 210 g.multidot.mm. The magnetic layer preferably has a thickness of not more than 0.5 .mu.m and the ferromagnetic powder preferably is ferromagnetic metallic powder or ferromagnetic hexagonal ferrite powder.
    Type: Grant
    Filed: April 13, 1993
    Date of Patent: October 3, 1995
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Toshio Kawamata, Masaya Kojima, Kazuhiro Niitsuma
  • Patent number: 5384175
    Abstract: A novel magnetic recording disc is provided comprising, a nonmagnetic support having thereon a nonmagnetic layer comprising nonmagnetic particles and a binder resin, and a magnetic layer comprising ferromagnetic particles and a binder resin, in this order. The nonmagnetic particles in the nonmagnetic layer are partially or entirely electrically conductive particles, the thickness of the magnetic layer is in the range of 0.5 .mu.m or less, and the orientation ratio of the ferromagnetic particles in the magnetic layer is 0.85 or more.A novel process for preparing the magnetic recording disc is provided. Further, a novel process for recording and reproduction of a signal having a shortest recordable wavelength of 1.5 .mu.m or less is provided, which utilizes the magnetic recording disc in conjunction with a magnetic head having a gap length (.delta.) of 0.50 .mu.m or less.
    Type: Grant
    Filed: October 13, 1992
    Date of Patent: January 24, 1995
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Masaya Kojima, Kazuhiro Niitsuma, Satoru Hayakawa, Toshio Kawamata, Yasushi Endo
  • Patent number: 5370917
    Abstract: A magnetic recording disc is disclosed which comprises a disc container with a liner comprising nonwoven fabric in which a flexible magnetic disc comprising a flexible non-magnetic support having on at least one side thereof a magnetic layer mainly comprising a ferromagnetic powder and a binder resin is rotably set, wherein said liner comprises (1) a nonwoven fabric layer mainly comprising rayon fiber on at least the side in contact with the magnetic layer, and (2) a nonwoven fabric layer mainly comprising polypropylene fiber, and said liner comprises from 70 to 80% by weight based on the liner of rayon fiber and from 20 to 30% by weight based on the liner of polypropylene fiber.
    Type: Grant
    Filed: June 10, 1993
    Date of Patent: December 6, 1994
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kazuhiro Niitsuma, Toshio Kawamata, Satoru Hayakawa
  • Patent number: 5300314
    Abstract: The present invention relates to a magnetic recording medium comprising, in the following order:(a) a nonmagnetic support;(b) a nonmagnetic layer comprising nonmagnetic particles and a binder resin; and(c) a magnetic layer comprising ferromagnetic particles and a binder resin;wherein said magnetic layer has a thickness of 0.8 .mu.m or less and said nonmagnetic layer and said magnetic layer are formed by a process which comprises the steps of coating a nonmagnetic layer coating solution on said nonmagnetic support, and then subsequently coating a magnetic layer coating solution on said nonmagnetic layer coating solution wile said nonmagnetic layer is wet and, further, wherein the solvent used in said nonmagnetic layer coating solution has a higher boiling point than the solvent used in said magnetic layer coating solution.
    Type: Grant
    Filed: December 21, 1992
    Date of Patent: April 5, 1994
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Satoru Hayakawa, Kazuhiro Niitsuma, Toshio Kawamata
  • Patent number: 5179487
    Abstract: A magnetic recording disk is disclosed which comprises a flexible magnetic disk comprising a nonmagnetic support having thereon a magnetic layer comprising ferromagnetic powders and binders which is rotatably loaded in a cartridge having a liner formed with a nonwoven fabric on the inside of the cartridge, wherein said liner comprises (A) two layers of a layer of the magnetic layer side comprising a nonwoven fabric of a mixed yarn of rayon fibers and polyester fibers formed on the side which contacts with the magnetic layer, and a layer of the cartridge side comprising a nonwoven fabric of acrylic fibers formed on the side which contacts with the cartridge; or (B) three layers of two layers comprising a nonwoven fabric of a mixed yarn of rayon fibers and polyester fibers, and an inter layer comprising acrylic fibers formed between the two layers.
    Type: Grant
    Filed: February 4, 1992
    Date of Patent: January 12, 1993
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kazuhiro Niitsuma, Satoru Hayakawa