Patents Examined by Louis Falasco
  • Leader tape and magnetic tape cartridge using the same
    Patent number: 7452616
    Abstract: A leader tape where an non-magnetic under layer that contains a powder and a binder and a magnetic upper layer are sequentially laminated on at least one face of a support, in which F5 values of the support in a machine direction (MD) and in a transverse direction (TD) are from 80 to 120 MPa respectively, the F5 value in MD is larger than that in TD, and a difference between the F5 value in MD and that in TD is 15 MPa or less.
    Type: Grant
    Filed: March 28, 2005
    Date of Patent: November 18, 2008
    Assignee: FUJIFILM Corporation
    Inventors: Masatoshi Takahashi, Mikio Ohno
  • Magnetic substrate, laminate of magnetic substrate and method for producing thereof
    Patent number: 7445852
    Abstract: A heat treatment was carried out in a pressurized condition on an amorphous metal ribbon containing Fe and Co as main components and being represented by the general formula: (Co(1?c)Fec)100?a?bXaYb. (In the formula, X represents at least one species of element selected from Si, B, C and Ge, Y represents at least one species of element selected from Zr, Nb, Ti, Hf, Ta, W, Cr, Mo, V, Ni, P, Al, Pt, Rh, Ru, Sn, Sb, Cu, Mn and rare earth elements, c, a and b satisfy 0?c?1.0, 10<a?35 and 0?b?30, respectively, and a and b are represented in terms of atomic %.) By carrying out a heat treatment in a pressurized condition in the same manner on a magnetic substrate comprising an amorphous metal ribbon and a heat resistant resin or a laminate of the substrates, not only the magnetic properties but also the mechanical properties and the processability are improved.
    Type: Grant
    Filed: July 6, 2004
    Date of Patent: November 4, 2008
    Assignee: Mitsui Chemicals, Inc.
    Inventors: Nobuhiro Maruko, Mitsunobu Yoshida, Hiroshi Watanabe, Takashi Ono, Hidenobu Nogi, Tomoyuki Nakata
  • Magnetic recording medium
    Patent number: 7438983
    Abstract: A magnetic recording medium is composed of a nonmagnetic support provided with on one side of the support a magnetic layer containing a ferromagnetic powder and a binder, and a backing layer on the other side of the nonmagnetic support, wherein the nonmagnetic support is a polyester film having an intrinsic viscosity of from 0.40 to 0.60 dl/g, and contains fillers having filler diameters of from 10 to 500 nm at a filler density of from 1/100 to 50/100 ?m2.
    Type: Grant
    Filed: January 28, 2005
    Date of Patent: October 21, 2008
    Assignee: FUJIFILM Corporation
    Inventors: Masatoshi Takahashi, Katsuhiko Meguro
  • Recording media with mechanically patterned landing zone
    Patent number: 7387848
    Abstract: A method of manufacturing a magnetic recording medium, comprises steps of providing a non-magnetic substrate for a magnetic medium, the substrate including at least one major surface having a contact start/stop (CSS) or landing zone and a data zone; and forming a pattern of recesses in the substrate surface in said CSS or landing zone by embossing utilizing a stamper having a surface including a negative image pattern of said pattern of recesses. Embodiments of the invention include magnetic media comprising a non-magnetic substrate including at least one major surface having a contact start/stop (CSS) or landing zone and a data zone, said substrate surface in said CSS or landing zone comprising an embossed pattern of recesses. In addition, the data zone of the substrate surface may include an embossed servo pattern formed simultaneously with the embossed pattern of recesses formed in the landing zone.
    Type: Grant
    Filed: August 18, 2003
    Date of Patent: June 17, 2008
    Assignee: Seagate Technology LLC
    Inventors: James Edward Angelo, Mukund Channagiri Rao, Alexei Hiram Sacks, Timothy Francis Ellis, David Kuo, Serge Jacques Fayeulle
  • Leader tape and magnetic tape cartridge using the same
    Patent number: 7384700
    Abstract: A leader tape comprising a support and a coating layer containing powder and a binder, wherein at least one surface of the leader tape has a center line average surface roughness (Ra) of from 10 to 60 nm, and depression hardness (DH) defined by the following equation (1) of from 60 to 140 kg/mm2 (0.588 to 1.372 GPa): DH=3.7926×10?2[Pmax/(Hmax)2](kg/mm2) ??(1) wherein Pmax is a maximum load and Hmax is a maximum displacement amount of an indenter.
    Type: Grant
    Filed: March 29, 2005
    Date of Patent: June 10, 2008
    Assignee: FUJIFILM Corporation
    Inventor: Satoru Hayakawa
  • Magnetic recording tape
    Patent number: 7381484
    Abstract: A magnetic recording tape comprising a magnetic layer, a flexible support and a back coat layer in this order, wherein the support is a polyester film having an intrinsic viscosity of from 0.40 to 0.60 dl/g and a number average molecular weight of from 12,000 to 24,000, a surface of the back coat layer has protrusions having a height of 100 nm or more measured with an atomic force microscope in a density of from 10 to 500 in 90 ?m square, and a ratio of a total number of protrusions having a height of 50 nm or more on the surface of the back coat layer to a total number of protrusions having a height of 100 nm or more on the surface of the back coat layer is from 10 to 100.
    Type: Grant
    Filed: January 28, 2005
    Date of Patent: June 3, 2008
    Assignee: FUJIFILM Corporation
    Inventor: Kiyomi Ejiri
  • Magnetic recording tape
    Patent number: 7381485
    Abstract: A magnetic recording tape comprising a nonmagnetic support and a magnetic layer containing ferromagnetic powder and a binder, wherein the nonmagnetic support has an intrinsic viscosity of from 0.40 to 0.60 dl/g and a number average molecular weight of from 12,000 to 24,000, and a distance between an apex of a maximum convexity and a valley of a maximum concavity of the nonmagnetic support on a cross section of an edge of the tape made by cutting the tape in a transverse direction is 2 ?m or less in the transverse direction.
    Type: Grant
    Filed: February 4, 2005
    Date of Patent: June 3, 2008
    Assignee: FUJIFILM Corporation
    Inventors: Tatsuo Ishikawa, Mikio Ohno, Tomohiro Ichikawa
  • Magnetic recording medium
    Patent number: 7368188
    Abstract: A magnetic recording medium including a polymer support having thereon at least one magnetic layer containing a ferromagnetic metal powder having an average major axis length of from 20 to 100 nm or a ferromagnetic hexagonal ferrite powder having an average tabular diameter of from 5 to 40 nm and a binder, the polymer support having an intrinsic viscosity of from 0.47 to 0.51 dL/g, a Young's modulus in the machine direction of from 7.0 to 8.6 GPa, a Young's modulus in the transverse direction of from 5.4 to 8.0 GPa, and a breaking strength in the transverse direction of from 370 to 450 MPa.
    Type: Grant
    Filed: January 19, 2005
    Date of Patent: May 6, 2008
    Assignee: FUJIFILM Corporation
    Inventors: Katsuhiko Meguro, Masatoshi Takahashi
  • Magnetic recording medium and magnetic recording device
    Patent number: 7368184
    Abstract: A magnetic recording medium which has a high areal density and reduced power consumption for recording operations, and a magnetic recording device incorporating the magnetic recording medium. The magnetic recording medium has an upper soft magnetic layer formed uniformly along a plane including the upper surface of a recording layer over the convex and concave portions of a concavo-convex pattern in the recording layer.
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: May 6, 2008
    Assignee: TDK Corporation
    Inventors: Akimasa Kaizu, Yoshikazu Soeno
  • Master carrier for magnetic transfer
    Patent number: 7368186
    Abstract: The master carrier for magnetic transfer of the invention comprises a support and a magnetic layer formed on the surface of the support, wherein an uneven transfer pattern that corresponds to the information to be transferred to a magnetic recording medium is formed in the surface of the magnetic layer, and a relief is formed in the site where the transfer pattern is not formed.
    Type: Grant
    Filed: July 23, 2004
    Date of Patent: May 6, 2008
    Assignee: FUJIFILM Corporation
    Inventors: Naoto Fujiwara, Seiji Kasahara, Kazuhiro Niitsuma
  • Magnetic recording medium
    Patent number: 7368189
    Abstract: A magnetic recording medium comprising: a magnetic layer containing ferromagnetic powder and a binder; a nonmagnetic support; and a back coat layer, in this order, wherein the nonmagnetic support contains polyester having an intrinsic viscosity of from 0.40 to 0.60 dl/g and a number average molecular weight of from 12,000 to 24,000, a surface of the magnetic layer on a side not having the nonmagnetic support has a surface roughness Ra of from 1 to 5 nm, and a surface of the back coat layer on a side not having the nonmagnetic support has a surface roughness Ra of from 6 to 20 nm.
    Type: Grant
    Filed: January 26, 2005
    Date of Patent: May 6, 2008
    Assignee: FUJIFILM Corporation
    Inventors: Mikio Ohno, Tatsuo Ishikawa, Tomohiro Ichikawa
  • Disk substrate for a perpendicular magnetic recording medium, perpendicular magnetic recording disk and manufacturing methods thereof
    Patent number: 7357998
    Abstract: A disk substrate for a perpendicular magnetic recording medium comprises a disk base member, a soft magnetic layer formed on the disk base member, and a protection layer formed on the soft magnetic layer. The soft magnetic layer and the protection layer are deposited by sputtering. A perpendicular magnetic recording disk comprises the above-mentioned disk substrate and at least a perpendicular magnetic recording layer formed thereon. The perpendicular magnetic recording layer is deposited on the disk substrate by sputtering after the disk substrate is heated.
    Type: Grant
    Filed: January 16, 2004
    Date of Patent: April 15, 2008
    Assignee: Hoya Corporation
    Inventors: Kong Kim, Junichi Horikawa
  • Magnetic recording media and method of forming them
    Patent number: 7351445
    Abstract: The present invention is directed to carrying out a high density magnetic recording to a material having a large coercive force by perpendicular magnetic recording head. By giving a patterning onto a soft magnetic under layer of a perpendicular two-layer recording media in sync with a period of a recording bit, a magnetic field from a write head can be allowed to converge to a soft magnetic column. Therefore, a magnetization reversal of the magnetic recording media material having a large anisotropic constant becomes possible, and then a high density magnetic recording can be achieved.
    Type: Grant
    Filed: June 12, 2006
    Date of Patent: April 1, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Chiseki Haginoya, Kaori Suzuki, Hisashi Kimura, Masaaki Futamoto, Hideo Matsuyama
  • Magnetic recording medium and method for manufacturing the same
    Patent number: 7323258
    Abstract: A magnetic recording medium which allows high density recording and has excellent durability can be obtained. A magnetic recording medium includes: a plurality of ferromagnetic material dots arranged on a soft magnetic layer formed on a non-magnetic substrate so as to be separated from one another; and carbon films which are formed on the respective ferromagnetic material dots, each carbon film having a smooth film face shape in a section passing through the center of each ferromagnetic material dot and a film thickness gradually decreasing from the center of the ferromagnetic material dot toward an outer edge thereof.
    Type: Grant
    Filed: September 23, 2004
    Date of Patent: January 29, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiyuki Kamata, Yuichi Ohsawa, Hiroyuki Hieda, Akira Kikitsu
  • Glass substrate for a magnetic disk, magnetic disk, and methods of producing the glass substrate and the magnetic disk
    Patent number: 7255943
    Abstract: On a principal surface of a glass disk substrate, a texture comprising a combination of an isotropic texture for stabilizing a flight of a magnetic head flying and traveling over a magnetic disk and an anisotropic texture for imparting a magnetic anisotropy to a magnetic layer of the magnetic disk is formed.
    Type: Grant
    Filed: May 13, 2004
    Date of Patent: August 14, 2007
    Assignee: Hoya Corporation
    Inventors: Takemi Miyamoto, Masao Takano
  • Magnetic recording medium
    Patent number: 7208237
    Abstract: The present invention provides a magnetic recording medium comprising a thin film magnetic layer of thickness in a range from 0.03 to 0.30 ?m, and having excellent surface smoothness and superior electromagnetic conversion characteristics. The magnetic recording medium comprises a lower non-magnetic layer containing at least a non-magnetic powder and a binder resin on one surface of a non-magnetic support, an upper magnetic layer containing at least a ferromagnetic powder and a binder resin on the lower non-magnetic layer, and a back coat layer on the other surface of the non-magnetic support, wherein the thickness of the upper magnetic layer is within the range from 0.03 to 0.30 ?m, the AFM surface roughness Ra of the upper magnetic layer is 6 nm or less, and the number of concavities with a depth of 30 nm or greater in the surface of the upper magnetic layer is 5 per 1 cm2 of surface area or less.
    Type: Grant
    Filed: April 14, 2004
    Date of Patent: April 24, 2007
    Assignee: TDK Corporation
    Inventors: Akihiko Seki, Takayoshi Kuwajima, Naoto Yajima, Hiroyuki Yamada, Kenichi Kitamura
  • Magnetic recording medium
    Patent number: 7183011
    Abstract: A magnetic recording medium for perpendicular magnetic recording system includes a nonmagnetic substrate and layers sequentially laminated on the substrate. The layers include a seed layer comprised of a metal or an alloy with a face centered cubic crystal structure, a nonmagnetic underlayer of a metal or an alloy with a hexagonal closest packed crystal structure, a magnetic layer having a granular structure including ferromagnetic crystalline grains with a hexagonal closest packed structure and nonmagnetic grain boundary region of mainly oxide surrounding the crystalline grains, a protective layer, and a liquid lubricant layer.
    Type: Grant
    Filed: January 17, 2003
    Date of Patent: February 27, 2007
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Miyabi Nakamura, Takahiro Shimizu, Hiroyuki Uwazumi, Naoki Takizawa, Tadaaki Oikawa
  • Ferrite thin film, method of manufacturing the same and electromagnetic noise suppressor using the same
    Patent number: 7160636
    Abstract: A ferrite film is formed by regularly arranging constituents such as magnetized grains or one analogous to that. In the ferrite film, the constituents have at least one of the uniaxial anisotropy and the multiaxial anisotropy. The ferrite film has the magnetic anisotropy or the magnetic isotropy. The ferrite film is formed by the use of the plating method in the presence of a magnetic field. Furthermore, an electromagnetic noise suppressor includes the ferrite film.
    Type: Grant
    Filed: September 11, 2003
    Date of Patent: January 9, 2007
    Assignee: NEC Tokin Corporation
    Inventors: Koichi Kondo, Okikuni Takahata, Tatsuya Chiba, Hiroshi Ono, Shigeyoshi Yoshida, Masanori Abe, Masahiro Yamaguchi
  • Magnetic recording medium
    Patent number: 7157163
    Abstract: The present invention provides a magnetic recording medium comprising a magnetic layer with excellent surface smoothness, which comprises a thin film magnetic layer of thickness in a range from 0.03 to 0.30 ?m that is ideal for short wavelength recording, and displays superior electromagnetic conversion characteristics. The magnetic recording medium comprises a magnetic layer containing at least a ferromagnetic powder and a binder resin on one surface of a non-magnetic support, wherein the thickness of the magnetic layer is within a range from 0.03 to 0.30 ?m, and the number of concavities with a depth of 30 nm or greater in the surface of the magnetic layer is 5 per 1 cm2 of surface area or less. Preferably, the value of the average depth Rv6 of the surface of the magnetic layer, as measured by a contact type surface roughness meter, is 12 nm or less.
    Type: Grant
    Filed: April 14, 2004
    Date of Patent: January 2, 2007
    Assignee: TDK Corporation
    Inventors: Naoto Yajima, Takayoshi Kuwajima, Akihiko Seki, Hiroyuki Yamada, Kenichi Kitamura
  • Magnetic transfer master medium, magnetic transfer method, and magnetic transfer master medium forming method
    Patent number: 7151641
    Abstract: A favorable magnetic transfer is performed to a perpendicular magnetic recording medium. A master medium is provided with a substrate on the surface of which protrusion portions, which form a pattern corresponding to the data that is to be transferred, having a pliable layer thereon have been formed. The master medium is further provided with a soft magnetic layer formed in the depression portions between the protrusion portions, and which is magnetically linked to the soft magnetic layer of the protrusion portions. The soft magnetic layer of the surface of the protrusion portions is conjoined with the magnetic recording layer of a perpendicular magnetic recording medium to form a conjoined body, and a transfer magnetic field is applied to the conjoined body in the direction from the substrate of the master medium toward the slave medium to perform the magnetic transfer.
    Type: Grant
    Filed: May 12, 2004
    Date of Patent: December 19, 2006
    Assignee: Fuij Photo Film Co., Ltd.
    Inventors: Masakazu Nishikawa, Kazunori Komatsu