公开(公告)号：US20220155702A1

公开(公告)日：2022-05-19

申请号：US17433593

申请日：2020-02-20

Applicant: POWDERTECH CO.,LTD.

Inventor： Makoto ISHIKAWA ,  Tetsuya UEMURA

IPC: G03G9/107 ,  C01G49/06 ,  G03G9/113 ,  H01F1/34

Abstract: The present invention relates to a ferrite particle, containing a crystal phase component containing a perovskite crystal represented by the compositional formula:
RZrO3 (provided that R represents an alkaline earth metal element), and having an apparent density in a range represented by the following formula: 1.90≤Y≤2.45 provided that Y in the formula is the apparent density (g/cm3) of the ferrite particle.

公开(公告)号：US11112716B2

公开(公告)日：2021-09-07

申请号：US16751031

申请日：2020-01-23

Applicant: POWDERTECH CO., LTD.

Inventor： Hiroki Sawamoto ,  Atsushi Nil ,  Yuji Ito ,  Hajime Akiba ,  Shinya Hanyu

IPC: G03G9/00 ,  G03G9/107 ,  G03G9/08

Abstract: The present invention relates to a carrier core material for electrophotographic developer, having a ferrite composition and having a supernatant transmittance of 85.0% or more, a method for producing the carrier core material, a carrier for electrophotographic developer, containing the carrier core material, and a developer containing the carrier.

公开(公告)号：US10996579B2

公开(公告)日：2021-05-04

申请号：US16483718

申请日：2018-01-15

Applicant: POWDERTECH CO., LTD.

Inventor： Hiroki Sawamoto ,  Tetsuya Uemura

IPC: G03G9/00 ,  G03G9/107 ,  G03G9/083 ,  G03G9/113 ,  H01F1/11

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.

公开(公告)号：US10919779B2

公开(公告)日：2021-02-16

申请号：US16466799

申请日：2017-12-12

Applicant: POWDERTECH CO., LTD.

Inventor： Koji Aga ,  Takashi Kojima

IPC: B32B5/16 ,  C01G49/02 ,  F16D69/02

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 μm 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.

公开(公告)号：US10593454B2

公开(公告)日：2020-03-17

申请号：US15511727

申请日：2015-09-02

Applicant: POWDERTECH CO., LTD.

Inventor： Koji Aga ,  Tetsuya Igarashi

IPC: H01F1/34 ,  B82Y40/00 ,  G03G9/107 ,  B82Y25/00 ,  C09C1/22 ,  C09D7/61 ,  C09D7/40 ,  C09D7/62 ,  C01G49/00 ,  C09D157/06 ,  C08K3/013 ,  C08K3/10 ,  C08K9/02 ,  C08K9/06

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.

公开(公告)号：US20200057399A1

公开(公告)日：2020-02-20

申请号：US16492894

申请日：2018-03-29

Applicant: POWDERTECH CO., LTD.

Inventor： Makoto ISHIKAWA ,  Hiroki SAWAMOTO ,  Tetsuya UEMURA

IPC: G03G9/107 ,  G03G9/113 ,  G03G9/08 ,  G03G9/083

Abstract: The present invention provides: a ferrite carrier core material for an electrophotographic developer, the material having a mesh passing amount of 3 wt % or less as indicated by the ratio of the weight of particles passing through a 16 μm-mesh to the weight of whole particles constituting a powder, and having a particle strength index of 2 wt % or less as indicated by a difference between the mesh passing amounts before and after crushing; a ferrite carrier which is for an electrophotographic developer and in which the surface of the ferrite carrier core material is coated with a resin; and an electrophotographic developer which includes the ferrite carrier and a toner.

公开(公告)号：US20200026211A1

公开(公告)日：2020-01-23

申请号：US16483718

申请日：2018-01-15

Applicant: POWDERTECH CO., LTD.

Inventor： Hiroki SAWAMOTO ,  Tetsuya UEMURA

IPC: G03G9/107 ,  G03G9/113 ,  H01F1/11 ,  G03G9/083

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.

公开(公告)号：US20190163081A1

公开(公告)日：2019-05-30

申请号：US16200338

申请日：2018-11-26

Applicant: POWDERTECH CO., LTD.

Inventor： Yuzuru YAMASAKI ,  Takao SUGIURA ,  Takeshi NAITO ,  Tetsuya UEMURA

IPC: G03G9/107 ,  G03G9/113

Abstract: Provided are a ferrite carrier core material for an electrophotographic developer having a full length L1 of grain boundary and a circumference length L2 of the core material in a cross-section of the core material, and satisfying a relationship of 2≤L1/L2≤9; a carrier for an electrophotographic developer including the ferrite carrier core material and a coating layer containing a resin provided on a surface of the ferrite carrier core material; and an electrophotographic developer including the carrier and a toner.

公开(公告)号：US20190135653A1

公开(公告)日：2019-05-09

申请号：US16095710

申请日：2017-04-11

Applicant: Powdertech Co., Ltd.

Inventor： Koji AGA ,  Tetsuya IGARASHI

IPC: C01G49/02 ,  C08L101/00 ,  C08K3/22 ,  H01F1/37 ,  A47J36/02

Abstract: Ferrite powder of the present invention is ferrite powder detectable with a metal detector, comprising: soft ferrite particles containing Mn of 3.5 mass % or more and 20.0 mass % or less and Fe of 50.0 mass % or more and 70.0 mass % or less. It is preferable that a volume average particle diameter of the particles constituting the ferrite powder is 0.1 μm or more and 100 μm or less. It is preferable that magnetization by a VSM measurement when magnetic field of 5 K·1000/4πA/m is applied is 85 A·m2/kg or more and 98 A·m2/kg or less.

公开(公告)号：US10036982B2

公开(公告)日：2018-07-31

申请号：US15007415

申请日：2016-01-27

Applicant: POWDERTECH CO., LTD.

Inventor： Hiroki Sawamoto ,  Tetsuya Uemura

IPC: G03G9/10 ,  G03G9/107 ,  G03G9/113 ,  G03G15/09

CPC classification number: G03G15/0928 ,  G03G9/10 ,  G03G9/1075 ,  G03G9/1131 ,  G03G9/1132 ,  G03G9/1138

Abstract: An object of the present invention is to provide a carrier in which decrease in specific gravity is achieved and a volatile organic compound (VOC) is reduced and to provide an electrophotographic developer using the carrier. There is provided a carrier including a core material coated with a resin, the core material including a magnetic component and a nonmagnetic component, wherein the sum total of volatile organic compounds is 1 ppb or more and 1.5 ppm or less. There is also provided an electrophotographic developer using the carrier.