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：US20230296999A1

公开(公告)日：2023-09-21

申请号：US18022961

申请日：2021-08-24

Applicant: POWDERTECH CO.,LTD.

Inventor： Makoto ISHIKAWA ,  Tetsuya UEMURA

IPC: G03G9/107

CPC classification number: G03G9/1085

Abstract: The present invention relates to a ferrite particle containing a crystal phase component containing a perovskite-type crystal represented by a composition formula of RZrO3 (wherein R is an alkaline earth metal element), and a Mg content of 0.45 mass % or less. The present invention also relates to a carrier core material for an electrophotographic developer, containing the ferrite particle; a carrier for an electrophotographic developer, containing the ferrite particle and a resin coating layer provided on a surface of the ferrite particle; and an electrophotographic developer containing the carrier for an electrophotographic developer and a toner.

公开(公告)号：US20230055795A1

公开(公告)日：2023-02-23

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：US20220019151A1

公开(公告)日：2022-01-20

申请号：US17430440

申请日：2020-02-13

Applicant: POWDERTECH CO.,LTD.

Inventor： Aya SAKUTA ,  Makoto ISHIKAWA ,  Hiroki SAWAMOTO ,  Tetsuya UEMURA

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

Abstract: The present invention relates to a carrier including: a magnetic core material; and a resin coating layer coating a surface of the magnetic core material, in which the resin coating layer contains a binder resin, and fluorine element-containing resin particles dispersed in the binder resin, the resin coating layer has a coefficient of variation of a film thickness of 25% or less, and the resin coating layer has an average value of the number of the fluorine element-containing resin particles being 3 particles/μm2 or more and 350 particles/μm2 or less per unit area in a cross section of the resin coating layer, and has a coefficient of variation thereof being 20% or less.

公开(公告)号：US10969706B2

公开(公告)日：2021-04-06

申请号：US16483709

申请日：2018-01-15

Applicant: POWDERTECH CO., LTD.

Inventor： Hiroki Sawamoto ,  Tetsuya Uemura

IPC: G03G9/083 ,  G03G9/107 ,  G03G9/113 ,  H01F1/36

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.

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：US20200241435A1

公开(公告)日：2020-07-30

申请号：US16751031

申请日：2020-01-23

Applicant: POWDERTECH CO., LTD.

Inventor： Hiroki SAWAMOTO ,  Atsushi NII ,  Yuji ITO ,  Hajime AKIBA ,  Shinya HANYU

IPC: 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：US20190337818A1

公开(公告)日：2019-11-07

申请号：US16466799

申请日：2017-12-12

Applicant: POWDERTECH CO., LTD.

Inventor： Koji AGA ,  Takashi KOJIMA

IPC: 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：US20190049870A1

公开(公告)日：2019-02-14

申请号：US16059405

申请日：2018-08-09

Applicant: POWDERTECH CO., LTD.

Inventor： Aya SAKUTA ,  Makoto ISHIKAWA ,  Hiroki SAWAMOTO ,  Tetsuya UEMURA

IPC: G03G9/107 ,  G03G9/113

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.

公开(公告)号：US20180008921A1

公开(公告)日：2018-01-11

申请号：US15545521

申请日：2016-01-25

Applicant: POWDERTECH CO., LTD.

Inventor： Koji AGA ,  Takao SUGIURA

IPC: B01D39/06 ,  C01G49/00 ,  B01J20/28 ,  B01J20/06 ,  B01J20/30 ,  H01F1/11 ,  B01J20/32

CPC classification number: B01D39/06 ,  B01J20/06 ,  B01J20/28004 ,  B01J20/28016 ,  B01J20/3021 ,  B01J20/3028 ,  B01J20/3042 ,  B01J20/3078 ,  B01J20/3204 ,  B01J20/3236 ,  B01J20/3293 ,  C01G49/00 ,  C01G49/0072 ,  C04B35/62821 ,  C04B2235/3206 ,  C04B2235/3262 ,  C04B2235/3274 ,  H01F1/11 ,  H01F1/112

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.