Patents Assigned to Powdertech Co., Ltd.
  • Patent number: 11029618
    Abstract: There is provided a carrier including a magnetic core material having a surface coated with a surfactant-containing resin mixture of an elemental fluorine-containing resin and a polyimide resin. The carrier has an elution amount of an eluted material into water in an elution test ranging from 180 ppm to 3,500 ppm.
    Type: Grant
    Filed: August 9, 2018
    Date of Patent: June 8, 2021
    Assignee: POWDERTECH CO., LTD.
    Inventors: Aya Sakuta, Makoto Ishikawa, Hiroki Sawamoto, Tetsuya Uemura
  • Patent number: 11032955
    Abstract: The present invention provides a powdered ferrite having high dispersibility in a resin and high electromagnetic shielding characteristics. The powdered ferrite comprises platy ferrite particles having a spinel crystal structure. The powdered ferrite comprises at least 50 number % platy ferrite particles each having at least one protrusion on a surface of the particle, and the protrusion has a shape selected from the group consisting of a rectangular pyramid, a truncated rectangular pyramid, an elongated rectangular pyramid, and combinations thereof.
    Type: Grant
    Filed: April 5, 2017
    Date of Patent: June 8, 2021
    Assignee: POWDERTECH CO., LTD.
    Inventors: Koji Aga, Tetsuya Igarashi
  • Patent number: 11014826
    Abstract: An object of the present invention is to provide ferrite particles having a high saturation magnetisation, and being excellent in the dispersibility in a resin, a solvent or a resin composition, a resin composition including the ferrite particles, and a resin film composed of the resin composition. The ferrite particles are a single crystalline body having an average particle size of 1 to 2000 nm, and Mn-based ferrite particles having a spherical shape, and have a saturation magnetisation of 45 to 95 Am2/kg. The resin composition includes the ferrite particles as a filler. The resin film is composed of the resin composition.
    Type: Grant
    Filed: February 22, 2017
    Date of Patent: May 25, 2021
    Assignee: POWDERTECH CO., LTD.
    Inventors: Takashi Kojima, Kazutaka Ishii, Takao Sugiura, Tetsuya Igarashi, Koji Aga
  • Patent number: 10996579
    Abstract: A magnetic core material for electrophotographic developer, satisfying a value of Expression (1): a+b×10+c+d+e+f, being from 200 to 1,400, when an amount of fluorine ion is denoted by a (ppm), an amount of chlorine ion is denoted by b (ppm), an amount of bromide ion is denoted by c (ppm), an amount of nitrite ion is denoted by d (ppm), an amount of nitrate ion is denoted by e (ppm), and an amount of sulfate ion is denoted by f (ppm), which are measured by combustion ion chromatography; and having a pore volume of from 30 to 100 mm3/g.
    Type: Grant
    Filed: January 15, 2018
    Date of Patent: May 4, 2021
    Assignee: POWDERTECH CO., LTD.
    Inventors: Hiroki Sawamoto, Tetsuya Uemura
  • Patent number: 10996576
    Abstract: Provided are a magnetic core material for electrophotographic developer and a carrier for electrophotographic developer, which are excellent in charge characteristics and strength and with which a satisfactory image free from defects can be obtained, and a developer containing the carrier. A magnetic core material for electrophotographic developer, having a sulfur component content of from 50 to 700 ppm in terms of a sulfate ion and a BET specific surface area of from 0.06 to 0.25 m2/g.
    Type: Grant
    Filed: December 25, 2017
    Date of Patent: May 4, 2021
    Assignee: POWDERTECH CO., LTD.
    Inventors: Hiroki Sawamoto, Tetsuya Uemura
  • Patent number: 10969706
    Abstract: Provided are a magnetic core material for electrophotographic developer and a carrier for electrophotographic developer, which are excellent in charging characteristics and strength with low specific gravity and with which a satisfactory image free of defects can be obtained, and a developer containing the carrier. A magnetic core material for electrophotographic developer, having a sulfur component content of from 60 to 800 ppm in terms of a sulfate ion and a pore volume of from 30 to 100 mm3/g.
    Type: Grant
    Filed: January 15, 2018
    Date of Patent: April 6, 2021
    Assignee: POWDERTECH CO., LTD.
    Inventors: Hiroki Sawamoto, Tetsuya Uemura
  • Publication number: 20210047200
    Abstract: Provided are: an Mn ferrite powder characterized by including a plurality of ferrite particles, having a volume-average particle diameter of 1-10 ?m, and having a 2.106 ?m volume-based cumulative distribution (sieved) of 0.1-50.0 vol %; and a resin composition characterized by including said powder and a resin material.
    Type: Application
    Filed: February 6, 2019
    Publication date: February 18, 2021
    Applicant: POWDERTECH CO., LTD.
    Inventors: Koji AGA, Takashi KOJIMA, Kazutaka ISHII, Tetsuya IGARASHI, Sho KUWAHARA
  • Patent number: 10919779
    Abstract: Provided is an iron oxide powder for a brake friction material which can be suitably used in a brake friction material that is less likely to cause problems regarding brake squealing and that provides superior braking performance. The iron oxide powder for a brake friction material according to the present invention is characterized by having an average particle size of 40 ?m or more and a saturation magnetization of 20 emu/g or less. The iron oxide powder preferably has a pore volume of 10-180 mm3/g. The iron oxide powder also preferably has a BET specific surface area of 0.05-1.20 m2/g.
    Type: Grant
    Filed: December 12, 2017
    Date of Patent: February 16, 2021
    Assignee: POWDERTECH CO., LTD.
    Inventors: Koji Aga, Takashi Kojima
  • Patent number: 10825593
    Abstract: An object of the present invention is to provide ferrite particles having high saturation magnetisation and electrical resistivity, excellent in dispersibility in a resin, a solvent, or a resin composition; a rein composition containing the ferrite particles; and a resin molding composed of the resin composition. A Ni-Zn-Cu ferrite particle is in a single crystalline body having an average particle diameter of 1 to 2000 nm, has a polyhedral particle shape, and comprises 5 to 10 wt % of Ni, 15 to 30 wt % of Zn, 1 to 5 wt % of Cu, and 25 to 50 wt % of Fe.
    Type: Grant
    Filed: June 7, 2017
    Date of Patent: November 3, 2020
    Assignee: POWDERTECH CO., LTD.
    Inventors: Takashi Kojima, Kazutaka Ishii, Takao Sugiura, Tetsuya Igarashi, Koji Aga
  • Patent number: 10775711
    Abstract: An object of the present invention is to provide a ferrite carrier core material for an electrophotographic developer having desired resistance properties and charging properties with small environmental variation of resistivity and charge amount while maintaining the advantages of ferrite carriers, a ferrite carrier for an electrophotographic developer, an electrophotographic developer using the ferrite carrier, and a method for manufacturing the ferrite carrier core material for an electrophotographic developer. In order to solve the problem, a ferrite carrier core material comprising ferrite particles containing 15 mass % or more and 25 mass % or less of Mn, 0.5 mass % or more and 5.0 mass % or less of Mg, 0.05 mass % or more and 4.0 mass % of Sr, and 45 mass % or more and 55 mass % or less of Fe, with Si localized in the surface thereof is used.
    Type: Grant
    Filed: March 29, 2017
    Date of Patent: September 15, 2020
    Assignee: POWDERTECH CO., LTD.
    Inventors: Takao Sugiura, Kazutaka Ishii, Koji Aga
  • Patent number: 10754271
    Abstract: A magnetic core material for electrophotographic developer, satisfying a value of Expression (1): a+b×10+c+d+e+f, being from 300 to 1,300, when an amount of fluorine ion is denoted by a (ppm), an amount of chlorine ion is denoted by b (ppm), an amount of bromide ion is denoted by c (ppm), an amount of nitrite ion is denoted by d (ppm), an amount of nitrate ion is denoted by e (ppm), and an amount of sulfate ion is denoted by f (ppm), which are measured by combustion ion chromatography, and having a BET specific surface area being from 0.06 to 0.25 m2/g.
    Type: Grant
    Filed: December 25, 2017
    Date of Patent: August 25, 2020
    Assignee: POWDERTECH CO., LTD.
    Inventors: Hiroki Sawamoto, Tetsuya Uemura
  • Patent number: 10603614
    Abstract: An object of the present invention is to provide ferrite particles for a filtering medium excellent in filtration ability having a small apparent density, capable of various properties maintained in the controllable state and filling a specified volume with a small amount, and a filtering medium made from the ferrite particles. In order to achieve the object, ferrite particles provided an outer shell structure containing Ti oxide for a filtering medium, and a filtering medium made from the ferrite particles are employed.
    Type: Grant
    Filed: January 25, 2016
    Date of Patent: March 31, 2020
    Assignee: POWDERTECH CO., LTD.
    Inventors: Koji Aga, Takao Sugiura
  • Patent number: 10593454
    Abstract: An object is to provide the ferrite particles used as a magnetic filler or a raw material for a molded product excellent in dispersibility as a powder and excellent in uniformity after molding and result the surface with small unevenness; and a method of manufacturing the particles. To achieve the object, Mn—Mg ferrite particles having an average particle size of 1 to 2000 nm and having a spherical shape are employed. It is preferable that the ferrite particles are produced by a method including subjecting of a ferrite raw material obtained through preparation of a ferrite composition to flame-spraying in air for ferritization followed by rapid cooling for solidifying of the ferrite.
    Type: Grant
    Filed: September 2, 2015
    Date of Patent: March 17, 2020
    Assignee: POWDERTECH CO., LTD.
    Inventors: Koji Aga, Tetsuya Igarashi
  • Patent number: 10585369
    Abstract: An object of the present invention is to provide a ferrite particle having a low apparent density, filling a specified volume with a low weight with various properties maintained in a controllable state, a ferrite carrier core material composed of the ferrite particle, and a ferrite carrier using the ferrite core material and an electrophotographic developer. To achieve the object, the ferrite particle having the outer shell structure containing the Ti oxide for the ferrite carrier core material, and the ferrite carrier using the ferrite particle as the ferrite carrier core material and the electrophotographic developer are employed.
    Type: Grant
    Filed: January 25, 2016
    Date of Patent: March 10, 2020
    Assignee: POWDERTECH CO., LTD.
    Inventors: Koji Aga, Takao Sugiura
  • Patent number: 10564561
    Abstract: An object of the present invention is to provide a ferrite carrier core material for an electrophotographic developer having desired resistance properties and charging properties with small environmental variation of resistivity and charge amount while maintaining the advantages of ferrite carriers, a ferrite carrier for an electrophotographic developer, an electrophotographic developer using the ferrite carrier, and a method for manufacturing the ferrite carrier core material for an electrophotographic developer. In order to solve the problem, a ferrite carrier core material comprising ferrite particles containing 15 mass % or more and 25 mass % or less of Mn, 0.5 mass % or more and 5.0 mass % or less of Mg, 0.05 mass % or more and 4.0 mass % of Sr, and 45 mass % or more and 55 mass % or less of Fe, with Zr localized in the surface thereof is used.
    Type: Grant
    Filed: March 29, 2017
    Date of Patent: February 18, 2020
    Assignee: POWDERTECH CO., LTD.
    Inventors: Takao Sugiura, Kazutaka Ishii, Koji Aga
  • Publication number: 20200003268
    Abstract: Provided is an iron oxide powder for a brake friction material which can be suitably used in a brake friction material that is less likely to cause problems regarding brake squealing and that provides superior braking performance. The iron oxide powder for a brake friction material according to a first embodiment of the present invention is characterized by having a sulfur content of 150 ppm or less as measured by combustion ion chromatography, and a saturation magnetization of 20 emu/g or less. The iron oxide powder for a brake friction material according to a second embodiment of the present invention is characterized by having an average particle size of 1.0 ?m or more, a chlorine content of 150 ppm or less as measured by combustion ion chromatography, and a saturation magnetization of 20 emu/g or less.
    Type: Application
    Filed: December 12, 2017
    Publication date: January 2, 2020
    Applicant: POWDERTECH CO., LTD.
    Inventors: Koji AGA, Takashi KOJIMA
  • Patent number: 10501333
    Abstract: The present invention provides a spherical ferrite powder that is excellent in filling ability and moldability if used as a filler, is excellent in handling ability, and is high in resistivity; a resin compound including the ferrite powder; and a molded product made of the resin compound. The spherical ferrite powder including 15 to 30 wt % of ferrite particles having the particle diameter less than 11 ?m and have the volume average particle diameter of 10 to 50 ?m; the resin compound including the ferrite powder; and the molded product made of the resin compound are employed.
    Type: Grant
    Filed: August 31, 2015
    Date of Patent: December 10, 2019
    Assignees: POWDERTECH CO., LTD., TATSUTA ELECTRIC WIRE & CABLE CO., LTD.
    Inventors: Koji Aga, Tetsuya Igarashi, Akio Takahashi
  • Publication number: 20190341177
    Abstract: An object of the present invention is to provide ferrite particles having high saturation magnetisation and electrical resistivity, excellent in dispersibility in a resin, a solvent, or a resin composition; a rein composition containing the ferrite particles; and a resin molding composed of the resin composition. A Ni-Zn-Cu ferrite particle is in a single crystalline body having an average particle diameter of 1 to 2000 nm, has a polyhedral particle shape, and comprises 5 to 10 wt % of Ni, 15 to 30 wt % of Zn, 1 to 5 wt % of Cu, and 25 to 50 wt % of Fe.
    Type: Application
    Filed: June 7, 2017
    Publication date: November 7, 2019
    Applicant: POWDERTECH CO., LTD.
    Inventors: Takashi KOJIMA, Kazutaka ISHII, Takao SUGIURA, Tetsuya IGARASHI, Koji AGA
  • Publication number: 20190337818
    Abstract: Provided is an iron oxide powder for a brake friction material which can be suitably used in a brake friction material that is less likely to cause problems regarding brake squealing and that provides superior braking performance. The iron oxide powder for a brake friction material according to the present invention is characterized by having an average particle size of 40 ?m or more and a saturation magnetization of 20 emu/g or less. The iron oxide powder preferably has a pore volume of 10-180 mm3/g. The iron oxide powder also preferably has a BET specific surface area of 0.05-1.20 m2/g.
    Type: Application
    Filed: December 12, 2017
    Publication date: November 7, 2019
    Applicant: POWDERTECH CO., LTD.
    Inventors: Koji AGA, Takashi KOJIMA
  • Publication number: 20190343027
    Abstract: The present invention provides a powdered ferrite having high dispersibility in a resin and high electromagnetic shielding characteristics. The powdered ferrite comprises platy ferrite particles having a spinel crystal structure. The powdered ferrite comprises at least 50 number % platy ferrite particles each having at least one protrusion on a surface of the particle, and the protrusion has a shape selected from the group consisting of a rectangular pyramid, a truncated rectangular pyramid, an elongated rectangular pyramid, and combinations thereof.
    Type: Application
    Filed: April 5, 2017
    Publication date: November 7, 2019
    Applicant: POWDERTECH CO., LTD
    Inventors: Koji AGA, Tetsuya IGARASHI