Patents by Inventor Shigeru Takaragi

Shigeru Takaragi 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: 9607741
    Abstract: The present invention relates to ferrite particles for bonded magnet, having a volume-average particle diameter of 2.1 to 2.7 ?m and a particle diameter ×90 of 4.3 to 5.4 ?m wherein the ×90 represents a particle diameter at which a cumulative percentage of particles under sieve (undersize particles) based on a volume thereof is 90%, when determined from a particle size distribution thereof measured by using a laser diffraction type particle size distribution measuring apparatus.
    Type: Grant
    Filed: April 18, 2014
    Date of Patent: March 28, 2017
    Assignee: TODA KOGYO CORPORATION
    Inventors: Yasuhiko Fujii, Minoru Ohsugi, Yasushi Nishio, Yosuke Koyama, Shigeru Takaragi
  • Patent number: 9249033
    Abstract: The present invention relates to ferrite particles for bonded magnets and a resin composition for bonded magnets which exhibit a good moldability, in particular, a good mechanical strength even when rapidly quenched upon injection-cooling, and is capable of producing a bonded magnet molded product having excellent magnetic properties, as well as a bonded magnet molded product such as a magnet roll using the ferrite particles and the resin composition. There are provided ferrite particles for bonded magnets which comprise phosphorus adsorbed and/or incorporated in ferrite, in which a content of the phosphorus in the ferrite is 120 to 5000 mg/kg (0.012 to 0.50% by weight) in terms of P; a resin composition for bonded magnets; and a magnet roll.
    Type: Grant
    Filed: March 14, 2008
    Date of Patent: February 2, 2016
    Assignee: TODA KOGYO CORPORATION
    Inventors: Yasuhiko Fujii, Yasushi Nishio, Kazuhisa Kanefuji, Tatsuya Ishida, Shigeru Takaragi
  • Publication number: 20140225023
    Abstract: The present invention relates to ferrite particles for bonded magnet, having a volume-average particle diameter of 2.1 to 2.7 ?m and a particle diameter ×90 of 4.3 to 5.4 ?m wherein the ×90 represents a particle diameter at which a cumulative percentage of particles under sieve (undersize particles) based on a volume thereof is 90%, when determined from a particle size distribution thereof measured by using a laser diffraction type particle size distribution measuring apparatus.
    Type: Application
    Filed: April 18, 2014
    Publication date: August 14, 2014
    Applicant: TODA KOGYO CORPORATION
    Inventors: Yasuhiko FUJII, Minoru OHSUGI, Yasushi NISHIO, Yosuke KOYAMA, Shigeru TAKARAGI
  • Patent number: 8741170
    Abstract: The present invention relates to ferrite particles for bonded magnet, having a volume-average particle diameter of 2.1 to 2.7 ?m and a particle diameter x90 of 4.3 to 5.4 ?m wherein the x90 represents a particle diameter at which a cumulative percentage of particles under sieve (undersize particles) based on a volume thereof is 90%, when determined from a particle size distribution thereof measured by using a laser diffraction type particle size distribution measuring apparatus.
    Type: Grant
    Filed: October 2, 2009
    Date of Patent: June 3, 2014
    Assignee: Toda Kogyo Corporation
    Inventors: Yasuhiko Fujii, Minoru Ohsugi, Yasushi Nishio, Yosuke Koyama, Shigeru Takaragi
  • Publication number: 20100108935
    Abstract: The present invention relates to ferrite particles for bonded magnets and a resin composition for bonded magnets which exhibit a good moldability, in particular, a good mechanical strength even when rapidly quenched upon injection-cooling, and is capable of producing a bonded magnet molded product having excellent magnetic properties, as well as a bonded magnet molded product such as a magnet roll using the ferrite particles and the resin composition. There are provided ferrite particles for bonded magnets which comprise phosphorus adsorbed and/or incorporated in ferrite, in which a content of the phosphorus in the ferrite is 120 to 5000 mg/kg (0.012 to 0.50% by weight) in terms of P; a resin composition for bonded magnets; and a magnet roll.
    Type: Application
    Filed: March 14, 2008
    Publication date: May 6, 2010
    Inventors: Yasuhiko Fujii, Yasushi Nishio, Kazuhisa Kanefuji, Tatsuya Ishida, Shigeru Takaragi
  • Publication number: 20100065771
    Abstract: The present invention relates to ferrite particles for bonded magnet, having a volume-average particle diameter of 2.1 to 2.7 ?m and a particle diameter x90 of 4.3 to 5.4 ?m wherein the x90 represents a particle diameter at which a cumulative percentage of particles under sieve (undersize particles) based on a volume thereof is 90%, when determined from a particle size distribution thereof measured by using a laser diffraction type particle size distribution measuring apparatus.
    Type: Application
    Filed: October 2, 2009
    Publication date: March 18, 2010
    Applicant: TODA KOGYO CORPORATION
    Inventors: Yasuhiko FUJII, Minoru Ohsugi, Yasushi Nishio, Yosuke Koyama, Shigeru Takaragi
  • Patent number: 6787059
    Abstract: A resing composition for bonded magnet of the present invention comprises: magnetic particles; and an aromatic polyamide resin comprising an aromatic carboxylic acid and an aliphatic diamine, which has a molar rational of residual end carboxyl groups to residual end amino groups of 0.1 to 1.0 and a solution viscosity of not more than 1.1 dl/g. The resin composition for bonded magnet is excellent inmoldability, and a bonded magnet using such a resing composition is excellent in mechanical strength and heat resistance.
    Type: Grant
    Filed: March 14, 2003
    Date of Patent: September 7, 2004
    Assignee: Toda Kogyo Corporation
    Inventors: Shigeru Takaragi, Minoru Ohsugi, Takahiro Araki, Takayoshi Ohara
  • Publication number: 20030181631
    Abstract: A resin composition for bonded magnet of the present invention comprises:
    Type: Application
    Filed: March 14, 2003
    Publication date: September 25, 2003
    Inventors: Shigeru Takaragi, Minoru Ohsugi, Takahiro Araki, Takayoshi Ohara
  • Patent number: 6300401
    Abstract: The disclosure described a material having a damping property, comprising 100 parts by weight of a binder resin composed of 85 to 99% by weight of at least one base resin selected from the group consisting of polypropylenes, polystyrenes, acrylonitrile-butadiene-styrene copolymers, polycarbonates, polyphenylene ethers and modified polyphenylene ethers and 1 to 15% by weight of styrene-isoprene-styrene block copolymer, and 1 to 20 parts by weight of iron compound particles.
    Type: Grant
    Filed: March 8, 1999
    Date of Patent: October 9, 2001
    Assignee: Toda Kogyo Corporation
    Inventors: Yasuhiko Fujii, Shigeru Takaragi, Tetsuro Toda, Tomohisa Moriya
  • Patent number: 6042757
    Abstract: An injection-molding device including an injection machine, a mold unit connected to the injection machine having separable molds defining a cavity for forming a molded product, and chucks next to the mold unit for removing a molded product from the mold. The molded product is initially coolied in the mold cavity then again cooled after removal from the mold unit. Plural chucks are advanced into and retreated from a region defined by the open molds, the chucks being a pair of blocks grasping the surface of the molded product, each block having a circulating path through which a heating medium is passed to cool the grasping surface. The injection-molding apparatus produces articles having high dimensional accuracy, for example, electronic parts such as a magnet roll or the like.
    Type: Grant
    Filed: May 28, 1998
    Date of Patent: March 28, 2000
    Assignee: Toda Kogyo Corporation
    Inventors: Masaharu Abe, Shigeru Takaragi, Hiroshi Yamamoto, Kyoichi Nakamura, Osamu Sasaki
  • Patent number: 5977235
    Abstract: The disclosure described a material having a damping property, comprising 100 parts by weight of a binder resin composed of 85 to 99% by weight of at least one base resin selected from the group consisting of polypropylenes, polystyrenes, acrylonitrile-butadiene-styrene copolymers, polycarbonates, polyphenylene ethers and modified polyphenylene ethers and 1 to 15% by weight of styrene-isoprene-styrene block copolymer, and 1 to 20 parts by weight of iron compound particles.
    Type: Grant
    Filed: May 13, 1997
    Date of Patent: November 2, 1999
    Assignee: Toda Kogyo Corporation
    Inventors: Yasuhiko Fujii, Shigeru Takaragi, Tetsuro Toda, Tomohisa Moriya
  • Patent number: 5731085
    Abstract: Disclosed are herein spherical magnetic particles comprising magnetic particles, a thermosetting resin and carbon which is derived from the thermosetting resin by carbonizing at least a part of the thermosetting resin, and having an average particle diameter of 1 to 1000 .mu.m.
    Type: Grant
    Filed: January 27, 1994
    Date of Patent: March 24, 1998
    Assignee: Toda Kogyo Corporation
    Inventors: Toshiyuki Hakata, Shigeru Takaragi
  • Patent number: 5196586
    Abstract: Disclosed herein are polydiphenyldiacetylenes having the following repeating unit (III): ##STR1## (wherein R.sup.1 denotes a hydrogen atom or a methoxy group; R.sup.2 denotes a hydrogen atom, a methoxy group or a methylamino group; R.sup.3 denotes a hydrogen atom or a trifluoromethyl group; and R.sup.4 denotes a hydrogen atom or a trifluoromethyl group; provided that R.sup.1 is not a hydrogen atom when R.sup.2 is hydrogen atom, and R.sup.3 is not a hydrogen atom when R.sup.4 is hydrogen atom).
    Type: Grant
    Filed: August 9, 1991
    Date of Patent: March 23, 1993
    Assignees: Toda Kogyo Corp., The Agency of Industrial Science and Technology
    Inventors: Hiro Matsuda, Shuji Okada, Hachiro Nakanishi, Masao Kato, Minoru Ohsugi, Shigeru Takaragi, Nanao Horiishi
  • Patent number: 5123989
    Abstract: Disclosed herein is a method for bonding a resin part, which comprises disposing a magnetic complex composed of a resin and magnetic particles as a heating-medium at the resin parts to be bonded, and applying an alternating magnetic field to the heating-medium by using a magnetic field generating means composed of an electromagnetic core and an exciting coil, thereby making said heating-medium generate heat for fuse-bonding said resins.
    Type: Grant
    Filed: June 11, 1990
    Date of Patent: June 23, 1992
    Assignees: Toda Kogyo Corporation, Dai-ichi High Frequency Company Limited
    Inventors: Nanao Horiishi, Kotaro Hirayama, Masanori Terasaki, Tetsuro Toda, Shigeru Takaragi
  • Patent number: 5118587
    Abstract: Disclosed herein are magnetic particles used for an electrostatic latent image developer comprising composite particles containing from more than 80% by weight to not more than 99% by weight of fine ferromagnetic particles and a cured phenol resin, and having a number-average particle diameter of from not less than 1 .mu.m to less than 10 .mu.m and an apparent density of not greater than 1.5 g/cm.sup.3.
    Type: Grant
    Filed: July 18, 1990
    Date of Patent: June 2, 1992
    Assignee: Toda Kogyo Corporation
    Inventors: Shigeru Takaragi, Toshiyuki Hakata, Kazuo Fujioka, Tetsuro Toda
  • Patent number: 5108862
    Abstract: Disclosed herein are composite carrier particles for electrophotography comprising 80 to 99% by weight of ferromagnetic fine particles and a phenol resin, and having a number-average particle diameter of 10 to 1,000 .mu.m, a bulk density of not more than 2.0 g /cm.sup.3, and a curved surface configuration, and a process for producing the same.
    Type: Grant
    Filed: February 16, 1990
    Date of Patent: April 28, 1992
    Assignees: Toda Kogyo Corp., Unitika Ltd.
    Inventors: Souichiro Kishimoto, Tsutomu Sakaida, Yoshiaki Echigo, Keiichi Asami, Tetsuro Toda, Kazuo Fujioka, Eiichi Kurita, Toshiyuki Hakata, Shigeru Takaragi