公开(公告)号：US11952286B2

公开(公告)日：2024-04-09

申请号：US16967197

申请日：2019-02-06

Applicant: POWDERTECH CO., LTD.

Inventor： Koji Aga ,  Takashi Kojima ,  Kazutaka Ishii ,  Tetsuya Igarashi ,  Sho Kuwahara

IPC: C01G49/00 ,  C08K3/22 ,  C08L29/04 ,  H01F1/34 ,  H01F1/37 ,  H05K9/00

CPC classification number: C01G49/0072 ,  C08L29/04 ,  H01F1/344 ,  H01F1/37 ,  H05K9/0081 ,  C01P2004/32 ,  C01P2004/51 ,  C01P2004/61 ,  C01P2006/11 ,  C01P2006/12 ,  C08K3/22 ,  C08K2201/005 ,  C08K2201/006 ,  C08K2201/01

Abstract: Provided are: an Mn ferrite powder characterized by including a plurality of ferrite particles, having a volume-average particle diameter of 1-10 μm, and having a 2.106 μm volume-based cumulative distribution (sieved) of 0.1-50.0 vol %; and a resin composition characterized by including said powder and a resin material.

公开(公告)号：US10775711B2

公开(公告)日：2020-09-15

申请号：US16084420

申请日：2017-03-29

Applicant: POWDERTECH CO., LTD.

Inventor： Takao Sugiura ,  Kazutaka Ishii ,  Koji Aga

IPC: G03G9/107 ,  G03G9/113 ,  C01G49/00 ,  G03G9/08

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.

公开(公告)号：US12119151B2

公开(公告)日：2024-10-15

申请号：US17795382

申请日：2021-01-27

Applicant: POWDERTECH CO., LTD.

Inventor： Koji Aga ,  Takashi Kojima ,  Takao Sugiura ,  Sho Kuwahara ,  Satomi Konno ,  Tadashi Tsuduki

IPC: H01F1/34 ,  C01G49/00

CPC classification number: H01F1/344 ,  C01G49/0072 ,  C01P2002/50 ,  C01P2004/32 ,  C01P2004/61 ,  C01P2006/40 ,  C01P2006/42 ,  C01P2006/80

Abstract: Provided are a ferrite powder capable of maintaining a high withstand voltage even when used in a resin composition having high magnetic properties and electrical resistivity and a high filling ratio, and a method for producing the same. A ferrite powder composed of spherical ferrite particles, wherein the ferrite powder contains iron (Fe): 55.0-70.0 mass % and manganese (Mn): 3.5-18.5 mass %, the ferrite powder containing more than 0.0 mass % to 7.5 mass % α-Fe2O3, and the ferrite powder has a volume average particle size (D50) of 15.0 μm or less.

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：US12134567B2

公开(公告)日：2024-11-05

申请号：US17794394

申请日：2021-01-22

Applicant: POWDERTECH CO., LTD.

Inventor： Takashi Kojima ,  Koji Aga

IPC: C01G49/00 ,  H01F1/34 ,  H01F1/37

Abstract: Provided are a ferrite powder that suppresses decreases in saturation magnetization and decreases in filler filling ratio and also suppresses inhibition of resin curing, and a method for producing the same. A ferrite powder composed of spherical ferrite particles, wherein the ferrite powder contains iron (Fe) 54.0-70.0 mass % and manganese (Mn) 3.5-18.5 mass %, has an average volume particle size of 2.0-20.0 μm, and has a carbon content of 0.100 mass % or lower.

公开(公告)号：US11072537B2

公开(公告)日：2021-07-27

申请号：US16095710

申请日：2017-04-11

Applicant: Powdertech Co., Ltd.

Inventor： Koji Aga ,  Tetsuya Igarashi

IPC: C01G49/00 ,  H01F1/20 ,  C01G49/02 ,  A47J36/02 ,  C08K3/22 ,  C08L101/00 ,  H01F1/37 ,  H05B6/74 ,  C08K7/16

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：US10585369B2

公开(公告)日：2020-03-10

申请号：US15544729

申请日：2016-01-25

Applicant: POWDERTECH CO., LTD.

Inventor： Koji Aga ,  Takao Sugiura

IPC: G03G9/113 ,  G03G9/10 ,  G03G9/107 ,  C01G49/00

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.

公开(公告)号：US11651881B2

公开(公告)日：2023-05-16

申请号：US16650647

申请日：2018-09-27

Applicant: POWDERTECH CO., LTD.

Inventor： Takashi Kojima ,  Kazutaka Ishii ,  Takao Sugiura ,  Tetsuya Igarashi ,  Koji Aga

IPC: H01F1/34 ,  H01F1/33 ,  H01F1/37 ,  H01F27/255 ,  C01G49/00 ,  C30B29/22

CPC classification number: H01F1/344 ,  C01G49/009 ,  C01G49/0072 ,  C30B29/22 ,  H01F1/33 ,  H01F1/37 ,  C01P2004/04 ,  C01P2004/32 ,  C01P2004/61 ,  C01P2004/62 ,  C01P2004/64 ,  C01P2006/42 ,  H01F27/255 ,  Y10T428/32

Abstract: Mn—Zn ferrite particles according to the present invention contain 44-60% by mass of Fe, 10-16% by mass of Mn and 1-11% by mass of Zn. The ferrite particles are single crystal bodies having an average particle diameter of 1-2,000 nm, and have polyhedral particle shapes, while having an average sphericity of 0.85 or more but less than 0.95.

公开(公告)号：US11572926B2

公开(公告)日：2023-02-07

申请号：US17666140

申请日：2022-02-07

Applicant: POWDERTECH CO., LTD.

Inventor： Koji Aga ,  Takashi Kojima

IPC: F16D69/02 ,  C01G49/06

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 μm 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.