Patents by Inventor Nobuyoshi Asada

Nobuyoshi Asada 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: 6815055
    Abstract: A magnetic recording medium is disclosed, comprising a support having thereon a lower layer containing a nonmagnetic powder or a ferromagnetic powder dispersed in a binder, and at least a magnetic layer containing a ferromagnetic powder dispersed in a binder provided on the lower layer, wherein the binder contains a polyurethane resin obtained from a polyester polyol comprising a specific diol, a chain extending agent and an organic diisocyanate, and the magnetic layer surface has a C/Fe peak ratio of from 7 to 11.
    Type: Grant
    Filed: July 17, 2002
    Date of Patent: November 9, 2004
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Satoshi Matsubaguchi, Yuichiro Murayama, Nobuyoshi Asada
  • Patent number: 6653001
    Abstract: Provided is a thin magnetic tape with good tracking and very little output variation in VTRs. The magnetic tape comprises a flexible support, a magnetic layer provided on one side of said flexible support and a backcoat layer provided on the reverse side of said flexible support. The magnetic tape has a stiffness equal to or less than 70 mg·mm2 in the width direction, an average meandering amount of a tape edge trajectory traced by each of both end in the width direction of said tape observed from the direction perpendicular to said magnetic layer surface is equal to or less than 15 &mgr;m in every end, and an intensity of a meandering component having a cycle of 20 to 200 mm is equal to or less than 30 percent of the intensity of a meandering component having a cycle of 20 to 10,000 mm.
    Type: Grant
    Filed: October 26, 2001
    Date of Patent: November 25, 2003
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Naoto Murao, Mikio Ohno, Nobuyoshi Asada, Youichi Hayata
  • Publication number: 20030108773
    Abstract: A magnetic recording medium is disclosed, comprising a support having thereon a lower layer containing a nonmagnetic powder or a ferromagnetic powder dispersed in a binder, and at least a magnetic layer containing a ferromagnetic powder dispersed in a binder provided on the lower layer, wherein the binder contains a polyurethane resin obtained from a polyester polyol comprising a specific diol, a chain extending agent and an organic diisocyanate, and the magnetic layer surface has a C/Fe peak ratio of from 7 to 11.
    Type: Application
    Filed: July 17, 2002
    Publication date: June 12, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Satoshi Matsubaguchi, Yuichiro Murayama, Nobuyoshi Asada
  • Publication number: 20020155324
    Abstract: Provided is a thin magnetic tape with good tracking and very little output variation in VTRs. The magnetic tape comprises a flexible support, a magnetic layer provided on one side of said flexible support and a backcoat layer provided on the reverse side of said flexible support. The magnetic tape has a stiffness equal to or less than 70 mg.mm2 in the width direction, an average meandering amount of a tape edge trajectory traced by each of both end in the width direction of said tape observed from the direction perpendicular to said magnetic layer surface is equal to or less than 15 &mgr;m in every end, and an intensity of a meandering component having a cycle of 20 to 200 mm is equal to or less than 30 percent of the intensity of a meandering component having a cycle of 20 to 10,000 mm.
    Type: Application
    Filed: October 26, 2001
    Publication date: October 24, 2002
    Inventors: Naoto Murao, Mikio Ohno, Nobuyoshi Asada, Youichi Hayata
  • Publication number: 20020076578
    Abstract: A magnetic recording medium comprises a support and coated layers, wherein the coated layers comprises: a lower layer containing a non-magnetic powder dispersed in a binder; and a magnetic layer containing a ferromagnetic powder dispersed in a binder, in the order, and the coated layers has a whole pore volume of 10 to 50 mm3/g.
    Type: Application
    Filed: November 2, 2001
    Publication date: June 20, 2002
    Inventors: Yasushi Hattori, Nobuyoshi Asada
  • Patent number: 5922483
    Abstract: A magnetic recording medium having a total thickness of not more than 11 .mu.m is disclosed, comprising a non-magnetic support having a magnetic layer comprising a ferromagnetic powder dispersed in a binder provided on one surface of the non-magnetic support and a back layer provided on the other surface of the non-magnetic support, wherein the non-magnetic support has a longitudinal Young's modulus (E.sub.MD) and a crosswise Young's modulus (E.sub.TD) such that the sum of E.sub.MD and E.sub.TD is not less than 1,200 kg/mm.sup.2 and the ratio of E.sub.MD to E.sub.TD is from 1/1 to 1/3 and an intrinsic viscosity of from 0.50 to 0.60 and the magnetic layer comprises a polyurethane resin with a weight-average molecular weight of from 30,000 to 60,000 having a component having a molecular weight of not more than 5,000 in an amount of not more than 4.5%.
    Type: Grant
    Filed: February 18, 1997
    Date of Patent: July 13, 1999
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Masatoshi Takahashi, Naoto Murao, Nobuyoshi Asada, Noburo Hibino
  • Patent number: 5827599
    Abstract: In the present invention, the anti-scrapability of the back layer of a magnetic recording medium is improved to reduce the frequency of occurrence of powder fall onto the surface of the magnetic layer and clogging between the magnetic head and the surface of the magnetic layer. As a result, a magnetic recording medium which is extremely less susceptible to dropout can be provided. A novel tape-shaped magnetic recording medium is provided which is obtained by longitudinally slitting a nonmagnetic support having on one side thereof a magnetic layer comprising a ferromagnetic powder dispersed in a binder and on the other side a back layer, wherein the edge face of said back layer doesn't protrude from the vertical line tangent to the highest protrusion on the slit section of said nonmagnetic support.
    Type: Grant
    Filed: November 8, 1996
    Date of Patent: October 27, 1998
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Naoto Murao, Masatoshi Takahashi, Nobuyoshi Asada, Jun-ichi Nakamigawa, Nobuyuki Kobayashi
  • Patent number: 5795645
    Abstract: A magnetic recording medium is disclosed, comprising a magnetic layer comprising a ferromagnetic powder and a binder provided on one side of a non-magnetic support and a backing layer provided on another side of said non-magnetic support, wherein said ferromagnetic powder is a ferromagnetic metal powder comprising Fe as a main component Co and containing Y in an amount of from 1 to 5 atm-% based on the total weight of Fe and Co in said ferromagnetic metal powder, and said binder comprises a polyurethane mainly comprising a diol component composed of a polyether polyol and a polyester polyol and a polyisocyanate component.
    Type: Grant
    Filed: March 19, 1996
    Date of Patent: August 18, 1998
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Masatoshi Takahashi, Nobuyoshi Asada, Hiroshi Hashimoto, Masashi Aonuma
  • Patent number: 5219670
    Abstract: A magnetic recording medium is disclosed, comprising a nonmagnetic support having provided on a first side of the support a magnetic layer containing a ferromagnetic powder and a binder, the ferromagnetic powder is a ferromagnetic metal powder having a water-soluble calcium content of 100 ppm or less, and the ratio of widthwise stiffness (TD) to lengthwise stiffness (MD) of the magnetic recording medium is in the range of from 0.65 to 1.00. In a preferred embodiment, the magnetic layer contains a saturated aliphatic acid having 14 to 24 carbon atoms, the magnetic layer has a dry thickness of from 0.5 to 3.5 .mu.m, the nonmagnetic support has a thickness of from 8 to 11 .mu.m, and the magnetic recording medium further comprises a backing layer having a dry thickness of from 0.1 to 1.0 .mu.m.
    Type: Grant
    Filed: October 7, 1991
    Date of Patent: June 15, 1993
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Mikio Ohno, Kiyomi Ejiri, Nobuyoshi Asada
  • Patent number: 4758468
    Abstract: The present invention relates to a magnetic recording medium which comprises a non-magnetic support having coated on opposite surfaces thereof a magnetic layer and a backing layer comprising a resin as a binder and non-magnetic particles, wherein the resin binder contains a polyurethane resin, a copolymer of vinylidene chloride and acrylonitrile, and a polyisocyanate compound; the non-magnetic particles contains fine carbon black having an average particle size of 30 to 150 m.mu. and coarse carbon black having an average particle size of 160 to 600 m.mu.; and the mixing weight ratio of the resin binder to the non-magnetic particles is within the range of 0.375:1 to 1:1 by weight. This magnetic recording medium has excellent electromagnetic properties and running durability.
    Type: Grant
    Filed: October 4, 1985
    Date of Patent: July 19, 1988
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Masatoshi Takahashi, Katsumi Ryoke, Nobuyoshi Asada, Eiichi Tadokoro