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: A magnetic composite includes: a non-metallic inorganic base material; and a ferrite layer provided on a surface of the non-metallic inorganic base material, and the non-metallic inorganic base material has a thickness of 2.0 ?m or more, the ferrite layer has a thickness (dF) of 2.0 ?m or more and 50.0 ?m or less, and contains spinel-type ferrite as a principal component, and a content of ?-Fe2O3 in the ferrite layer is 3.0 mass % or more and 25.0 mass % or less.

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.

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 ?m, and has a carbon content of 0.100 mass % or lower.

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 % ?-Fe2O3, and the ferrite powder has a volume average particle size (D50) of 15.0 ?m or less.

Abstract: The present invention provides a ferrite particle containing: a ferrite particle body having a spinel crystal structure belonging to a space group Fd-3m and having a spinel composition represented by the following formula (1); and a coating layer having a spinel crystal structure belonging to the space group Fd-3m and coating a surface of the ferrite particle body, in which the coating layer is a layer obtained by subjecting the ferrite represented by the following formula (1) to a heat treatment, and a content ratio of the coating layer in the ferrite particle obtained by subjecting a powder X-ray diffraction pattern to Rietveld analysis is 5 mass % or more and 35 mass % or less, and the ferrite particle satisfies a specific formula (2). The present invention also provides a carrier for an electrophotographic developer.

Abstract: A ferrite particle having a spinel crystal structure belonging to a space group Fd-3m and having a ferrite composition represented by a specific formula, a carrier for an electrophotographic developer including the ferrite particle and a resin coating layer configured to coat a surface of the ferrite particle, an electrophotographic developer including the carrier for an electrophotographic developer and a toner, and a ferrite particle production method for producing the ferrite particle.

Abstract: Provided are a ferrite powder that inhibits magnetic loss at frequencies lower than 100 MHZ, and when applied to a composite material or a composite body, is capable of preventing particles from coming off without loss of moldability and filling properties, a ferrite resin composite material, and electromagnetic shielding material, electronic material, or electronic component. This ferrite powder is a Mn—Zn ferrite powder containing at least spherical or polyhedral ferrite particles having a spinel phase as a main phase. The ferrite particles also have, at respective surfaces thereof, a step structure having a convex polygonal contour. Furthermore, the BET specific surface area of the ferrite powder is 0.35-10.00 m2/g, and the contained amount of the zinc oxide (ZnO) phase thereof is 0-0.8 mass %.

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.

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.

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.

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.

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.