Patents by Inventor Yasushi Sakai

Yasushi Sakai 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: 20070082414
    Abstract: A perpendicular magnetic recording medium having compatibility between low noises and high thermal stability is provided. In the present medium having at least an underlayer, a magnetic recording layer, a protective layer and a lubricant layer sequentially stacked on a nonmagnetic substrate, the underlayer is composed from at least one element selected from Ru, Rh, Os, Ir and Pt, the magnetic recording layer has a granular structure, and its composition is Co100-a-b-cPtaCrbBc)100-dMd (M is an oxide or a nitride of at least one element of Cr, Al, Ti, Si, Ta, Hf, Zr, Y and Ce, and a, b, c and d meet the condition of 0<a?40, 2?b ?12, 0.5?c?5 and 4?d?12). A soft magnetic backing layer 2 and a seed layer 3 may be formed between the nonmagnetic substrate and the underlayer.
    Type: Application
    Filed: March 14, 2005
    Publication date: April 12, 2007
    Applicant: FUJI ELECTRIC DEVICE TECHNOLOGY CO., LTD.
    Inventors: Sadayuki Watanabe, Yasushi Sakai
  • Publication number: 20070059561
    Abstract: The quantity of oxide contained in a magnetic layer is controlled to control the crystal grains and the segregation structure for ensuring low noise characteristic in a granular magnetic layer of a perpendicular magnetic recording medium. The granular magnetic layer consists of ferromagnetic crystal grains and a nonmagnetic grain boundary region mainly of an oxide surrounding the ferromagnetic crystal grains. The perpendicular magnetic recording medium has a nonmagnetic underlayer composed of a metal or alloy having hexagonal closest-packed crystal structure. The ferromagnetic crystal grain is composed of an alloy containing at least cobalt and platinum. The volume proportion of the nonmagnetic grain boundary region mainly of the oxide falls within a range of 15% to 40% of the volume of the total magnetic layer.
    Type: Application
    Filed: August 31, 2006
    Publication date: March 15, 2007
    Applicant: FUJI ELECTRIC HOLDINGS CO., LTD.
    Inventors: Hiroyuki UWAZUMI, Yasushi SAKAI, Tadaaki OIKAWA, Miyabi NAKAMURA
  • Publication number: 20070009654
    Abstract: A perpendicular magnetic recording medium has a magnetic recording layer with ferromagnetic crystalline grains and nonmagnetic and nonmetallic grain boundary region surrounding the grains. The surface of its underlayer, before forming the magnetic recording layer, is exposed to an O2 or N2 atmosphere or an atmosphere of rare gas and O2 or N2, to attach the O2 or N2 as nucleation sites for promoting growth of the nonmagnetic and nonmetallic region. By forming the magnetic recording layer thereafter, both ferromagnetic crystalline grains and the nonmagnetic and nonmetallic grain boundary region are formed from the initial stage of the growth of the magnetic recording layer. Thus, a magnetic recording layer having excellent segregation structure can be formed.
    Type: Application
    Filed: September 13, 2006
    Publication date: January 11, 2007
    Applicant: Fuji Electric Co., Ltd.
    Inventors: Sadayuki Watanabe, Yasushi Sakai
  • Patent number: 7150895
    Abstract: A perpendicular magnetic recording medium has a magnetic recording layer with ferromagnetic crystalline grains and nonmagnetic and nonmetallic grain boundary region surrounding the grains. The surface of its underlayer, before forming the magnetic recording layer, is exposed to an O2 or N2 atmosphere or an atmosphere of rare gas and O2 or N2, to attach the O2 or N2 as nucleation sites for promoting growth of the nonmagnetic and nonmetallic region. By forming the magnetic recording layer thereafter, both ferromagnetic crystalline grains and the nonmagnetic and nonmetallic grain boundary region are formed from the initial stage of the growth of the magnetic recording layer. Thus, a magnetic recording layer having excellent segregation structure can be formed.
    Type: Grant
    Filed: March 17, 2003
    Date of Patent: December 19, 2006
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Sadayuki Watanabe, Yasushi Sakai
  • Patent number: 7147942
    Abstract: The quantity of oxide contained in a magnetic layer is controlled to control the crystal grains and the segregation structure for ensuring low noise characteristic in a granular magnetic layer of a perpendicular magnetic recording medium. The granular magnetic layer consists of ferromagnetic crystal grains and a nonmagnetic grain boundary region mainly of an oxide surrounding the ferromagnetic crystal grains. The perpendicular magnetic recording medium has a nonmagnetic underlayer composed of a metal or alloy having hexagonal closest-packed crystal structure. The ferromagnetic crystal grain is composed of an alloy containing at least cobalt and platinum. The volume proportion of the nonmagnetic grain boundary region mainly of the oxide falls within a range of 15% to 40% of the volume of the total magnetic layer.
    Type: Grant
    Filed: December 9, 2002
    Date of Patent: December 12, 2006
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Hiroyuki Uwazumi, Yasushi Sakai, Tadaaki Oikawa, Miyabi Nakamura
  • Publication number: 20060258746
    Abstract: A person, who has symptoms including difficulty in going to sleep, feeling languid after waked up or having a hard time awaking, is desirous of a medicament and a nutritional food that can alleviate the symptoms and improve his or her health. Specifically, one object of the present invention is to provide an orally administered agent, a food and drink, or a food additive which can be used for improving the process of going to sleep and waking. An orally administered agent, a food and drink, or a food additive for improving the process of going to sleep and waking, containing ornithine or a salt thereof as an active ingredient can be provided according to the present invention.
    Type: Application
    Filed: November 8, 2005
    Publication date: November 16, 2006
    Applicant: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Toshikazu Kamiya, Takeshi Shibasaki, Asuka Otofuji, Yasushi Sakai, Akemi Ogawa, Miho Komatsu
  • Publication number: 20060177703
    Abstract: A perpendicular magnetic recording medium is disclosed that achieves improved recordability without deteriorating thermal stability by reducing the switching field. A perpendicular magnetic recording medium of the invention has a first magnetic recording layer and a second magnetic recording layer between with is interposed a coupling layer that ferromagnetically couples the two layers. The first and second magnetic recording layers satisfy an inequality Ku1T1>Ku2T2 in the case where Hk1 >Hk2 and an inequality Ku1T1<Ku2T2 in the case where Hk1<Hk2, where Hk1 and Hk2 are anisotropy magnetic fields, Ku1 and Ku2 are uniaxial anisotropy constants, and T1 and T2 are thicknesses of the first magnetic recording layer and the second recording layer, respectively. An exchange coupling energy between the magnetic recording layers is preferably at least 5×10?3 erg/cm2.
    Type: Application
    Filed: July 1, 2005
    Publication date: August 10, 2006
    Applicant: Fuji Electric Device Technology Co., Ltd.
    Inventors: Shunji Takenoiri, Yasushi Sakai
  • Publication number: 20060172005
    Abstract: An object of the present invention relates to a tablet which comprises an active ingredient and a cyclodextrin or a cyclodextrin derivative and rapidly disintegrates in the oral cavity, etc. The present invention provides a tablet in which 70% by mass or more of the components of the tablet is a cyclodextrin or a cyclodextrin derivative and a method for manufacturing a tablet comprising the steps of: mixing constituent components of the tablet which comprises as constituent components an active ingredient and a cyclodextrin or a cyclodextrin derivative and in which 70% by mass or more of the total constituent components of the tablet is the cyclodextrin or the cyclodextrin derivative; and subsequently tableting the resultant mixture.
    Type: Application
    Filed: July 8, 2004
    Publication date: August 3, 2006
    Applicant: Kyowa Hakko Kogyo Co.,Ltd.
    Inventors: Takahiro Hara, Masao Kimura, Yasushi Sakai
  • Publication number: 20060154113
    Abstract: A perpendicular magnetic recording medium and a magnetic recording device with the medium are disclosed. Ferromagnetic crystal grains in a granular magnetic recording layer are grown with a constant grain diameter in a columnar shape, and the nonmagnetic grain boundaries comprise at least two types of oxides or nitrides, preferably of elements selected from Cr, Si, Al, Ti, Ta, Hf, Zr, Y, Ce, and B. The maximum G1 of absolute values of standard Gibbs free energy of formation for oxidation of ferromagnetic elements composing the ferromagnetic crystal grains, the minimum G2 and the second smallest G3 of absolute values of standard Gibbs free energy of formation per 1 mol of oxygen molecules for oxidation of elements composing the nonmagnetic grain boundaries satisfy inequalities G1<G2<G3 and (G2?G1)>(G3?G2) and G3?G2 is preferably smaller than 200 kJ/mol.
    Type: Application
    Filed: December 8, 2005
    Publication date: July 13, 2006
    Applicant: Fuji Electric Device Technology Co., Ltd.
    Inventors: Sadayuki Watanabe, Yasushi Sakai
  • Publication number: 20060147760
    Abstract: A perpendicular magnetic recording medium is provided that achieves excellent magnetic performance by suppressing spike noises due to a soft magnetic backing layer, as well as good productivity. The perpendicular magnetic recording medium comprises at least a soft magnetic backing layer, an antiferromagnetic layer, an nonmagnetic underlayer, and a magnetic recording layer sequentially laminated on a nonmagnetic substrate, wherein the magnetic recording layer has a granular structure, the nonmagnetic underlayer is composed of ruthenium or a ruthenium alloy having an hcp structure having a thickness of at least 5 nm, the antiferromagnetic layer is composed of an alloy having an fcc structure and containing at least manganese, and the antiferromagnetic layer is laminated directly on the soft magnetic backing layer. Preferably, the antiferromagnetic layer is composed of an IrMn alloy, and the soft magnetic backing layer has an fcc structure and contains at least nickel and iron.
    Type: Application
    Filed: December 2, 2005
    Publication date: July 6, 2006
    Applicant: Fuji Electric Device Technology Co., Ltd.
    Inventors: Hiroyuki Uwazumi, Yasushi Sakai, Shunji Takenoiri, Sadayuki Watanabe
  • Patent number: 7067206
    Abstract: A perpendicular magnetic recording medium has a granular magnetic layer and a nonmagnetic underlayer of a metal or an alloy having a hexagonal close packed (hcp) crystal structure. A seed layer of a metal or an alloy of a face-centered cubic (fcc) crystal structure is provided under the nonmagnetic underlayer. Such a perpendicular magnetic recording medium exhibits excellent magnetic characteristics even when the thickness of the underlayer or the total thickness of the underlayer and the seed layer is very thin. Excellent magnetic characteristics can be obtained even when of the substrate is not preheated. Accordingly, a nonmagnetic substrate, such as a plastic resin can be employed to reduce the manufacturing cost.
    Type: Grant
    Filed: August 23, 2002
    Date of Patent: June 27, 2006
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Hiroyuki Uwazumi, Yasushi Sakai, Tadaaki Oikawa, Miyabi Nakamura
  • Patent number: 7045225
    Abstract: A perpendicular magnetic recording suitable for mass production and having suppressed spike noise has at least a seed layer, an orientation controlling layer, an antiferromagnetic layer, a soft magnetic layer, a magnetic recording layer, a protective layer, and a liquid lubricant layer formed on a nonmagnetic substrate. The orientation controlling layer is composed of a material comprising at least Ni and Fe, and having at least one element selected from the group consisting of B, Nb, and Si. The seed layer is composed of Ta. Further, after depositing the antiferromagnetic layer and the soft magnetic layer, but before depositing the magnetic recording layer, the substrate is heated to a blocking temperature or higher, and thereafter cooled to the blocking temperature or below while applying a static magnetic field in a radial direction of the substrate.
    Type: Grant
    Filed: November 26, 2003
    Date of Patent: May 16, 2006
    Assignee: Fuji Electric Device Technology Co., Ltd.
    Inventors: Sadayuki Watanabe, Yasushi Sakai
  • Patent number: 7042849
    Abstract: A method for controlling data transmission in a network system configured by a first node, a second node, and a third node. The first node has a first port connected to the second node and a second port connected to the third node. The first node enables data received by the first port from the second node to be transmitted by the second port to the third node. The received data includes information of the node to which the received data is addressed. The method compares the information of the first node with the address information included in the received data, temporarily disconnects the third node from the first node when the received data is not addressed to the third node.
    Type: Grant
    Filed: March 20, 2001
    Date of Patent: May 9, 2006
    Assignee: Fujitsu Limited
    Inventor: Yasushi Sakai
  • Publication number: 20060093867
    Abstract: A perpendicular magnetic recording medium includes a soft magnetic backing layer, an underlayer, a nonmagnetic intermediate layer, and a magnetic recording layer sequentially deposited on a nonmagnetic substrate. The underlayer can contain cobalt, nickel, and iron and have an fcc structure and exhibit soft magnetic property. The underlayer preferably contains nickel in a range of 30 to 88 at % and iron in a range of 0.1 to 22 at %. The underlayer can further contain Si, B, Nb, N, Ta, Al, Pd, Cr, or Mo. The nonmagnetic intermediate layer preferably contains at least one element selected from Ru, Re, Pd, Ir, Pt, and Rh. The magnetic recording layer preferably has a granular structure. A seed layer can be further provided between the soft magnetic backing layer and the underlayer.
    Type: Application
    Filed: October 21, 2005
    Publication date: May 4, 2006
    Applicant: Fuji Electric Device Technology Co., Ltd.
    Inventors: Shunji Takenoiri, Yasushi Sakai
  • Publication number: 20060077337
    Abstract: Without using screwing members such as a screw and a nut, and extra parts such as a bush, a cylindrical pin and a slip-off preventive pin, and with a simple structure, the spectacle lens can surely be held. A taper pin 21 is provided projecting on a lens holding member (endpiece 4 and bridge 5) for holding a spectacle lens 10, and a taper hole 11 having approximately the same size as the taper pin is provided on the spectacle lens, and the taper pin is directly press-fitted into the taper hole, thereby surely holding the spectacle lens by a press-contact between an inner circumferential surface of the taper hole and an outer circumferential surface of the taper pin. The taper pin is press-fitted in a thickness direction of the spectacle lens 10.
    Type: Application
    Filed: May 28, 2004
    Publication date: April 13, 2006
    Applicant: Hoya Corporation
    Inventor: Yasushi Sakai
  • Publication number: 20060014052
    Abstract: A perpendicular medium is disclosed in which an isolation structure of an underlayer is formed using a simple method as in a conventional manufacturing process for a medium of continuous films. The method suppresses dispersion of alignment and reduced magnetic cluster size in a magnetic recording layer. The perpendicular medium exhibits high recording density owing to thin film thickness of the underlayer. A perpendicular magnetic recording medium includes at least an underlayer and a magnetic recording layer sequentially laminated on a nonmagnetic substrate. The underlayer consists of crystal grains and an amorphous grain boundary, and the crystal grain has a shape holding a relation (an area of a bottom region at an initial stage of growth)>(an area of a top region).
    Type: Application
    Filed: July 1, 2005
    Publication date: January 19, 2006
    Applicant: Fuji Electric Device Technology Co., Ltd.
    Inventors: Sadayuki Watanabe, Yasushi Sakai
  • Publication number: 20050186450
    Abstract: A perpendicular magnetic recording medium is disclosed in which each magnetic crystal grain in the magnetic recording layer has a multilayer structure and has a configuration like a truncated cone shape, in which the crystal grain of the final layer deposited in the film surface side at the final stage is smaller than the diameter of the crystal grain in the initial layer deposited on the substrate side at the initial stage. The invention improves S/N (signal output to noise ratio) by enhancing signal output and reducing noises. The medium is produced by a simple manufacturing method suitable for mass production, and provides a medium of high recording density by improving recording resolution.
    Type: Application
    Filed: January 25, 2005
    Publication date: August 25, 2005
    Applicant: Fuji Electric Device Technology Co., Ltd.
    Inventors: Shunji Takenoiri, Yasushi Sakai
  • Publication number: 20050186358
    Abstract: A perpendicular magnetic recording medium and method thereof, includes a nonmagnetic substrate; a soft magnetic under layer; an intermediate layer; a bilayer magnetic recording layer; a protective layer; and a liquid lubricant layer. According to a following order, the soft magnetic under layer, the intermediate layer, the bilayer magnetic recording layer, the protective layer, and the liquid lubricant layer are sequentially stacked on the nonmagnetic substrate. The bilayer magnetic recording layer includes a first magnetic layer including a CoCr alloy crystalline film, and a second magnetic layer including a rare earth-transition metal alloy noncrystalline film.
    Type: Application
    Filed: April 27, 2005
    Publication date: August 25, 2005
    Applicant: FUJI ELECTRONIC CO., LTD.
    Inventors: Yasushi Sakai, Hiroyuki Uwazumi, Kazuo Enomoto, Sadayuki Watanabe
  • Publication number: 20050153169
    Abstract: A perpendicular magnetic recording medium has a magnetic recording layer and laminated magnetic layers composed of different materials. In a first magnetic layer of the magnetic recording layer, ferromagnetic grains are surrounded by a nonmagnetic grain boundary region composed principally of oxide and/or nitride. In a second magnetic layer of the magnetic recording layer, ferromagnetic grains are surrounded by a nonmagnetic grain boundary region composed principally of chromium. The recording medium has an intermediate layer composed of a material having hcp or fcc structure. Advantageously, a heating process is conducted after forming the first magnetic layer and before forming the second magnetic layer. The medium achieves improvement in electromagnetic conversion characteristics and simultaneously improvement in corrosion resistance to provide a perpendicular magnetic recording medium with high recording density and simultaneously high reliability.
    Type: Application
    Filed: June 14, 2004
    Publication date: July 14, 2005
    Inventors: Sadayuki Watanabe, Yasushi Sakai, Hiroyuki Uwazumi
  • Patent number: 6913837
    Abstract: A perpendicular magnetic recording medium and method thereof, includes a nonmagnetic substrate; a soft magnetic under layer; an intermediate layer; a bilayer magnetic recording layer; a protective layer; and a liquid lubricant layer. According to a following order, the soft magnetic under layer, the intermediate layer, the bilayer magnetic recording layer, the protective layer, and the liquid lubricant layer are sequentially stacked on the nonmagnetic substrate. The bilayer magnetic recording layer includes a first magnetic layer including a CoCr alloy crystalline film, and a second magnetic layer including a rare earth-transition metal alloy noncrystalline film.
    Type: Grant
    Filed: July 8, 2002
    Date of Patent: July 5, 2005
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Yasushi Sakai, Hiroyuki Uwazumi, Kazuo Enomoto, Sadayuki Watanabe