Abstract: A magnetic composite includes a resin base material and a ferrite layer provided on a surface of the resin base material, the resin base material has a thickness of 10 ?m or more, and the ferrite layer has a thickness of 2.0 ?m or more, contains spinel-type ferrite as a principal component, and has a ratio of 0.00 or more and 0.03 or less, wherein the ratio is of an integrated intensity of a 222 plane to an integrated intensity of a 311 plane in X-ray diffraction analysis.
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:
Grant
Filed:
February 6, 2019
Date of Patent:
April 9, 2024
Assignee:
POWDERTECH CO., LTD.
Inventors:
Koji Aga, Takashi Kojima, Kazutaka Ishii, Tetsuya Igarashi, Sho Kuwahara
Abstract: A magnetic composite includes a metal base material and a ferrite layer provided on a surface of the metal base material, the metal base material has a thickness of 0.001 ?m or more, and the ferrite layer has a thickness of 2.0 ?m or more, contains spinel-type ferrite as a principal component, and has a ratio of 0.00 or more and 0.03 or less, the ratio being of an integrated intensity of a (222) plane to an integrated intensity of a (311) plane in X-ray diffraction analysis.
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.
Abstract: The present invention relates to a ferrite particle containing a crystal phase component containing a perovskite crystal represented by a compositional formula: RZrO3 (provided that R represents an alkaline earth metal element), having a surface roughness Rz of 0.8 µm or more and 3.5 µm or less, and having a standard deviation Rz? of the surface roughness Rz falling in a range represented by the following formula 0.15 × Rz ? Rz? ? 0.60 × Rz. The ferrite particle can be used as an electrophotographic developer carrier core material. In addition, an electrophotographic developer carrier and an electrophotographic developer can be obtained.
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.
Type:
Grant
Filed:
September 27, 2018
Date of Patent:
May 16, 2023
Assignee:
POWDERTECH CO., LTD.
Inventors:
Takashi Kojima, Kazutaka Ishii, Takao Sugiura, Tetsuya Igarashi, Koji Aga
Abstract: The present invention relates to a ferrite particle containing a crystal phase component containing a perovskite crystal represented by a compositional formula: RZrO3 (provided that R represents an alkaline earth metal element), having a surface roughness Rz of 2.0 ?m or more and 4.5 ?m or less, and satisfying the following formulas: 6.5?log H1000?8.5 and 0.80?log H1000/log H100?1.00. The ferrite particle can be used as an electrophotographic developer carrier core material. In addition, an electrophotographic developer carrier and an electrophotographic developer can be obtained.
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.
Abstract: An object of the present invention is to provide ferrite particles having a high magnetic permeability in a frequency band of 1 MHz to 1 GHz. Another object is to provide a resin composition containing the ferrite particles and an electromagnetic wave shielding material composed of the resin composition. The ferrite particles are composed of a single crystalline body having an average particle size of 1 to 2000 nm and has a spherical particle shape, wherein the ferrite particles contain substantially no Zn, 3 to 25 wt % of Mn, and 43 to 65 wt % of Fe, and a real part ?? of a complex magnetic permeability measured using a molding composed of the ferrite particles and a binder resin has a maximal value in a frequency band of 100 MHz to 1 GHz.
Type:
Grant
Filed:
May 31, 2017
Date of Patent:
January 3, 2023
Assignee:
POWDERTECH CO., LTD.
Inventors:
Takashi Kojima, Kazutaka Ishii, Takao Sugiura, Tetsuya Igarashi, Koji Aga
Abstract: The ferrite powder of the present invention is a ferrite powder containing a plurality of ferrite particles, wherein the ferrite particles each are a single crystal body having an average particle diameter of 1-2,000 nm, and have a polyhedron shape, and wherein the ferrite particles each contain 2.0-10.0 mass % of Sr, and 55.0-70.0 mass % of Fe.
Type:
Grant
Filed:
March 30, 2018
Date of Patent:
December 6, 2022
Assignee:
POWDERTECH CO., LTD.
Inventors:
Kazutaka Ishii, Koji Aga, Takao Sugiura, Takashi Kojima
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 ?m-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.
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.
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.
Abstract: The present invention provides: a ferrite particle containing a crystal phase component containing a perovskite crystal represented by the compositional formula RZrO3 (where R is an alkaline earth metal element); and an electrophotographic developer carrier core material, an electrophotographic developer carrier, and an electrophotographic developer containing the ferrite particles.
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.
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/?m2 or more and 350 particles/?m2 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.
Type:
Application
Filed:
February 13, 2020
Publication date:
January 20, 2022
Applicant:
POWDERTECH CO.,LTD.
Inventors:
Aya SAKUTA, Makoto ISHIKAWA, Hiroki SAWAMOTO, Tetsuya UEMURA
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.
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.
Abstract: To provide a magnetic core material and carrier for electrophotographic developer, which have small environmental dependence of the electric resistance, can suppress the carrier scattering, and can stably provide good images; a developer contains the carrier; and methods for producing them. The magnetic core material satisfying a value of Formula (1): a+b×10+c+d+e+f, being from 20 to 150, when a fluoride ion amount is denoted by a (ppm), a chloride ion amount is denoted by b (ppm), a bromide ion amount is denoted by c (ppm), a nitrite ion amount is denoted by d (ppm), a nitrate ion amount is denoted by e (ppm), and a sulfate ion amount is denoted by f (ppm), which are measured by a combustion ion chromatography method.
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 ?m or more and 100 ?m or less. It is preferable that magnetization by a VSM measurement when magnetic field of 5 K·1000/4?A/m is applied is 85 A·m2/kg or more and 98 A·m2/kg or less.