Patents by Inventor Nobutaka Yamaguchi

Nobutaka Yamaguchi 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: 4840842
    Abstract: An abrasive tape comprises a flexible substrate, and an abrasive layer overlaid on the flexible substrate by applying an abrasive coating composition containing abrasive grains and a binder onto the flexible substrate and drying the applied abrasive coating composition. The binder contains a vinyl chloride resin having a --SO.sub.3 M group, where M represents Li, Na or K, and an epoxy group.
    Type: Grant
    Filed: September 25, 1987
    Date of Patent: June 20, 1989
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Nobutaka Yamaguchi, Masaaki Fujiyama, Masami Suzuki, Yasuyuki Yamada
  • Patent number: 4822672
    Abstract: An abrasive tape comprises a flexible non-magnetic substrate, and an abrasive coating film applied onto the flexible non-magnetic substrate and formed by kneading abrasive grains, a binder and an additive. The binder contains a resin which has, at a side chain, at least one polar group selected from the group consisting of ##STR1## where M represents a hydrogen atom, lithium, sodium, or potassium, M.sub.1 represents a hydrogen atom, lithium, sodium, potassium, or an alkyl group, and M.sub.2 represents a hydrogen atom, lithium, sodium, potassium, or an alkyl group.
    Type: Grant
    Filed: February 27, 1987
    Date of Patent: April 18, 1989
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Nobutaka Yamaguchi, Eiichi Tadokoro, Takahito Miyoshi
  • Patent number: 4767644
    Abstract: A method of making an abrasive tape comprises the steps of preparing an abrasive composition at least from abrasive grains and a binder, applying the abrasive composition onto a flexible substrate, and drying the applied abrasive composition. The step of preparing the abrasive composition comprises kneading processing and attritor dispersion processing which are carried out for at least a part of the abrasive grains and at least a part of the binder.
    Type: Grant
    Filed: April 20, 1987
    Date of Patent: August 30, 1988
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Nobutaka Yamaguchi, Masaaki Fujiyama, Masami Suzuki
  • Patent number: 4764423
    Abstract: An abrasive tape comprises a flexible non-magnetic substrate, and an abrasive coating film applied onto the flexible non-magnetic substrate and formed by kneading an abrasive material, a binder, and a lubricant essentially consisting of a fatty acid, a fatty acid ester, a silicone oil, and a surface active agent.
    Type: Grant
    Filed: October 17, 1986
    Date of Patent: August 16, 1988
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Nobutaka Yamaguchi, Eiichi Tadokoro
  • Patent number: 4756960
    Abstract: An abrasive tape comprises a flexible non-magnetic substrate, and an abrasive coating film essentially consisting of an abrasive material, a binder and an additive kneaded together and applied onto the flexible non-magnetic substrate. The abrasive material has a Mohs hardness of 6 or higher, and the binder essentially consists of a vinyl chloride-vinyl acetate copolymer, a prepolymer having an isocyanate group at a terminal, and an organic amine.
    Type: Grant
    Filed: October 17, 1986
    Date of Patent: July 12, 1988
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Nobutaka Yamaguchi, Eiichi Tadokoro
  • Patent number: 4752524
    Abstract: An abrasive tape comprises a flexible non-magnetic substrate, and an abrasive coating film applied onto the flexible non-magnetic substrate and formed by kneading an abrasive material and a binder essentially consisting of a vinyl chloride-vinyl acetate-maleic acid copolymer, a polyamide resin and an epoxy resin.
    Type: Grant
    Filed: October 17, 1986
    Date of Patent: June 21, 1988
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Nobutaka Yamaguchi, Eiichi Tadokoro
  • Patent number: 4734325
    Abstract: A magnetic recording medium comprising a non-magnetic support having provided thereon a magnetic layer being provided on one surface of the support and a backing layer being provided on the surface of the support opposite to said magnetic layer, the backing layer contains binder and non-magnetic particles comprised of (i) corbon black having an average particle size of 0.1 to 1.0 .mu.m and (ii) particles of abrasives having a Mohs' hardness of at least 6 and an average particle size of 1 .mu.m or less, with the non-magnetic particles in said backing layer being used in an amount of 40 to 300 parts by weight per 100 parts by weight of binder.
    Type: Grant
    Filed: October 4, 1985
    Date of Patent: March 29, 1988
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Katsumi Ryoke, Nobutaka Yamaguchi, Masatoshi Takahashi, Kazuko Hanai, Hideaki Kosha, Eiichi Tadokoro
  • Patent number: 4728569
    Abstract: A magnetic recording medium is described, comprising a magnetic layer coated on one side of a non-magnetic support and a backing layer coated on the opposite side of the non-magnetic support, wherein the backing layer is provided after the magnetic layer has been subjected to calendering treatment and the backing layer comprises (i) non-magnetic particles including carbon black particles having an average particle diameter of from 0.1 to 1 .mu.m and (ii) a binder composition comprising from 50 to 95 wt % of a resin having a 100% modulus at 150 kg/cm.sup.2 or less based on the total weight of the binder composition, and the weight ratio of non-magnetic particles to binder composition contained in the backing layer is from 300/100 to 40/100.
    Type: Grant
    Filed: November 19, 1985
    Date of Patent: March 1, 1988
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Katsumi Ryoke, Nobutaka Yamaguchi, Masatoshi Takahashi, Kazuko Hanai, Hideaki Kosha, Eiichi Tadokoro
  • Patent number: 4696858
    Abstract: A magnetic recording medium is described, comprising a non-magnetic support having provided thereon a magnetic layer being provided on one surface of the support and a backing layer being provided on the surface of the support opposite to said magnetic layer, the backing layer containing (A) a binder comprised of resin having a 100% modulus of 150 kg/cm.sup.2 or less present in an amount of 50 to 95 wt % based on the total weight amount of binder and (B) non-magnetic particles comprised of (i) carbon black having an average particle size of more than 0.1 .mu.m to 1.0 .mu.m, and (ii) carbon black having an average particle size of 0.01 .mu.m to 0.1 .mu.m in a weight ratio of carbon black (i)/carbon black (ii) of 95/5 to 5/95, with the non-magnetic particles in the backing layer being present in an amount of 40 to 300 parts by weight per 100 parts by weight of the total binder.
    Type: Grant
    Filed: October 18, 1985
    Date of Patent: September 29, 1987
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Katsumi Ryoke, Nobutaka Yamaguchi, Masatoshi Takahashi, Kazuko Hanai, Hideaki Kosha, Eiichi Tadokoro
  • Patent number: 4686139
    Abstract: A magnetic recording medium is described, comprising a non-magnetic support having a magnetic layer and a backing layer which is provided on the surface of the support opposite to the magnetic layer, the backing layer containing (a) non-magnetic particles comprising carbon black having an average particle diameter of 0.1 to 1.0 .mu.m, (b) a binder comprising (i) a resin having 150 kg/cm.sup.2 or less of 100% modulus in an amount of at least 50 wt % based on the total amount of binder, and (ii) a diphenyl methane diisocyanate type hardening agent, with the amount of non-magnetic particles to total contained in the backing layer being 40 to 300 parts by weight of non-magnetic particles per 100 parts by weight of binder.
    Type: Grant
    Filed: September 20, 1985
    Date of Patent: August 11, 1987
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Katsumi Ryoke, Nobutaka Yamaguchi, Masatoshi Takahashi, Kazuko Hanai, Hideaki Kosha, Eiichi Tadokoro
  • Patent number: 4663217
    Abstract: A magnetic recording medium comprised of a nonmagnetic support base having a magnetic recording layer on one surface thereof and a backing layer on the other surface thereof is disclosed. The backing layer is comprised of (1) carbon black having a particle size in the range of 10 to 150 m.mu., (2) graphite having a particle size of 3.mu. or less, and (3) a curing agent. By utilizing this particular backing layer the resulting recording medium has improved durability with respect to the backing layer and shows a decreased in the number of dropouts and scratches during use.
    Type: Grant
    Filed: August 19, 1985
    Date of Patent: May 5, 1987
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Nobutaka Yamaguchi, Shinobu Iida, Masahiro Utsumi, Norio Nasu, Eiichi Tadokoro
  • Patent number: 4650720
    Abstract: A magnetic recording medium is disclosed which comprises a non-magnetic support having provided thereon a magnetic recording layer and a backing layer on the opposite surface thereof, wherein said magnetic recording layer contains a fatty acid, said backing layer contains a cellulose resin, and said non-magnetic support has a Young's modulus of 7.times.10.sup.10 to 1.times.10.sup.13 dyn/cm.sup.2.
    Type: Grant
    Filed: April 11, 1984
    Date of Patent: March 17, 1987
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Nobutaka Yamaguchi, Takahito Miyoshi, Toshimitu Okutu, Noburo Hibino, Eiichi Tadokoro, Masaaki Fujiyama
  • Patent number: 4649072
    Abstract: A magnetic recording medium comprising a non-magnetic support having provided thereon a magnetic layer on one side and a backing layer on the other side, wherein the backing layer contains (1) non-magnetic powders containing carbon black having an average particle diameter of from 0.1 to 1 .mu.m; (2) two or more binders wherein (a) at least one of the binders is a resin having a 100% modulus of from 15 to 150 kg/cm.sup.2 in an amount of from 50 to 95 wt % based on the total amount of the binders in the backing layer, and (b) the rest binder(s) is/are a resin other than the resin having a 100% modulus of from 15 to 150 kg/cm.sup.2, and the weight ratio of all the non-magnetic powders to all the binders in the backing layer is from 300:100 to 40:100; and (3) a polyisocyanate in an amount of from 15 to 40 wt % based on the total amount of the binders in the backing layer.
    Type: Grant
    Filed: September 23, 1985
    Date of Patent: March 10, 1987
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Katsumi Ryoke, Nobutaka Yamaguchi, Masatoshi Takahashi, Kazuko Hanai, Hideaki Kosha, Eiichi Tadokoro
  • Patent number: 4647501
    Abstract: A magnetic recording material, which comprises a non-magnetic support having provided on one side thereof a magnetic layer and on the other side thereof a backing layer is disclosed. The binder of the backing layer is comprised of a combination of a cellulose resin, a vinylidene chloride resin, a polyurethane resin and a polyisocyanate. Use of the backing layer increases the durability of the tape and aids in preventing drop out.
    Type: Grant
    Filed: December 24, 1985
    Date of Patent: March 3, 1987
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Nobutaka Yamaguchi, Shinobu Iida, Norio Nasu, Katsumi Ryoke, Toshimitu Okutu, Kenichi Masuyama
  • Patent number: 4647503
    Abstract: A magnetic recording medium is disclosed. The medium is comprised of a non-magnetic support base having a surface with a center line average loughness (Ra) of not more then 0.035 .mu.m, having coated thereon a magnetic layer. The magnetic layer is comprised of a ferromagnetic powder, a fatty acid ester and two types of carbon black dispersed in a binder. The first type of carbon black has an average primary particles sizes of 10 to 30 m.mu.. The second type of carbon black has an average primary particle size of 60 to 120 m.mu.. The first type of carbon black and second type of carbon black are present in a mixing weight ratio in the range of 60/40 to 95/5. The magnetic recording medium has excellent electromagnetic properties and provides a tape having good running property and durability.
    Type: Grant
    Filed: November 25, 1985
    Date of Patent: March 3, 1987
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Nobutaka Yamaguchi, Masaaki Fujiyama, Kazuo Kato, Akira Kashiwagi
  • Patent number: 4626469
    Abstract: A magnetic recording material, which comprises a magnetic layer coated on a non-magnetic support is disclosed. The magnetic layer contains both carbon black fine powder having a mean primary grain size of less than 10 m.mu. and carbon black coarse powder having a mean primary grain size in the range of 50 to 120 m.mu. in a mixing ratio ranging from 95/5 to 5/95. The material is improved in both RF output and audio output.
    Type: Grant
    Filed: June 17, 1983
    Date of Patent: December 2, 1986
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Nobutaka Yamaguchi, Kenichi Masuyama, Shinobu Iida, Masaaki Fujiyama
  • Patent number: 4619855
    Abstract: A magnetic recording medium is disclosed. The medium is comprised of a support base having an average center line roughness (Ra) of 0.035 .mu.m or less which has coated thereon a magnetic layer. The magnetic layer is comprised of ferromagnetic fine particles dispersed in a binder comprising (1) a polymer selected from the group consisting of nitrocellulose resins, vinyl chloride-vinyl acetate resins and vinyl chloride-vinyl propionate type resins; (2) a urethane resin; and (3) a compound having 2 or more acrylate groups or methacrylate groups in the molecule thereof. The magnetic layer is cured by radiation with electron beams and has excellent electromagnetic properties as well as high durability. The magnetic medium provides less abrasiveness and the magnetic coating composition is stable and homogeneous during storage.
    Type: Grant
    Filed: October 18, 1983
    Date of Patent: October 28, 1986
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Tsutomu Okita, Nobutaka Yamaguchi, Hiroshi Hashimoto
  • Patent number: 4617226
    Abstract: A novel magnetic recording medium comprising a non-magnetic support, a magnetic recording layer, and an intermediate layer containing an electroconductive polymer. An optional second intermediate layer contains carbon black and is provided on either surface of the first intermediate layer. The magnetic recording medium has low surface electric resistance, and when used as a video tape, has both a high video S/N ratio and improved stability of video S/N with the passage of time.
    Type: Grant
    Filed: August 21, 1984
    Date of Patent: October 14, 1986
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Nobutaka Yamaguchi, Masahiro Utumi, Masaaki Fujiyama, Takahito Miyoshi
  • Patent number: 4601946
    Abstract: A magnetic recording medium is disclosed which comprises a non-magnetic support having provided thereon a magnetic recording layer consisting ferromagnetic powder and containing graphite and a fatty acid ester.
    Type: Grant
    Filed: July 26, 1984
    Date of Patent: July 22, 1986
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Shinobu Iida, Nobutaka Yamaguchi, Fumiaki Tsukuda, Masaaki Fujiyama, Eiichi Tadokoro
  • Patent number: 4579778
    Abstract: A magnetic recording medium is disclosed which comprises a non-magnetic support, having a Young's modulus of 7.times.10.sup.10 to 1.times.10.sup.13 dyn/cm.sup.2, having coated on opposite surfaces, a magnetic recording layer comprising ferromagnetic particles and a fatty acid ester and a backing layer comprising a cellulose resin.
    Type: Grant
    Filed: April 25, 1984
    Date of Patent: April 1, 1986
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Nobutaka Yamaguchi, Norio Nasu, Eiichi Tadokoro, Masaaki Fujiyama