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.

Provided is a magnetic carrier, including: a ferrite core particle; and a coating resin, in which: the coating resin has a surface resin layer and a resin composition in the stated order from a surface side thereof; the resin composition contains a resin, and an inorganic particle or carbon black that is subjected to a hydrophilic treatment; the surface resin layer contains a resin, is free of the inorganic particle or the carbon black, and has a thickness of from 0.01 μm or more to 4.00 μm or less; and a moisture percentage change between a moisture percentage when the magnetic carrier is left to stand under an environment of 30° C. and 80% RH for 24 hours, and a moisture percentage when the magnetic carrier is left to stand under an environment of 23° C. and 5% RH for 24 hours after the standing is 0.030 mass % or less.

Ferrite particles have, as a main component, a material represented by a composition formula M.sub.xFe.sub.3−xO.sub.4 (where M is at least one type of metal selected from a group made of Mg, Mn, Ca, Ti, Cu, Zn, Sr and Ni, 0<x<1), where the maximum height Rz of the particles falls within a range of 1.40 μm to 1.90 μm, and the degree of distortion Rsk of the particles falls within a range of −0.25 to −0.07. In this way, when the ferrite particles are used as the carrier of an electrophotographic image forming apparatus, even if an image formation speed is increased, the occurrence of a failure is reduced for a long period of time.

An electrostatic charge image developing carrier includes a magnetic particle and a coating resin layer that covers the magnetic particle and contains an inorganic particle, and the following relation 1 is satisfied: 0<(C−A)/(B−A)≤0.40 (relation 1), in which A is a Net intensity of Si determined by an X-ray fluorescence analysis of a carrier A that is a carrier taken out from a developer A obtained by mixing a carrier and a toner with a silica particle externally added, B is a Net intensity of Si determined by the X-ray fluorescence analysis of a carrier B that is a carrier taken out from a developer B obtained by adding a silica particle to the developer A to obtain a mixture and stirring the mixture with a Turbula stirring apparatus for 20 minutes, and C is a Net intensity of Si determined by the X-ray fluorescence analysis of a carrier C that is a carrier taken out from a mixture C obtained by stirring a toner particle and the carrier B being the carrier taken out from the developer B for 2 minutes with the Turbula stirring apparatus.

An electrostatic charge image developing carrier, contains: a magnetic particle; and a coating resin layer coating the magnetic particle and containing inorganic particles, in which an area ratio of the inorganic particles that is a ratio of a total area of the inorganic particles to an area of the coating resin layer in a cut surface of the coating resin layer along a thickness direction of the coating resin layer is 10% or more and 50% or less.

A magnetic carrier having a ferrite-type core material and a resin coat layer present on the surface of the ferrite-type core material, wherein the ferrite-type core material contains a magnetic ferrite-type core material particle and an amino group-bearing primer compound; the resin coat layer contains a coating resin A that is a polymer of monomer containing a (meth)acrylate ester having an alicyclic hydrocarbon group; the content of the amino group-bearing primer compound in the ferrite-type core material and the content of the resin coat layer in the magnetic carrier are within the prescribed range.

A carrier for developing electrostatic latent images is provided. The carrier includes a magnetic core particle and a resin layer coating a surface of the magnetic core particle. The resin layer includes a particulate material A having a volume average particle diameter (a) and a particulate material B having a volume average particle diameter (b). The volume average particle diameter (a) of the particulate material A is the largest among volume average particle diameters of all particulate materials included in the resin layer, and an inequation 100≧(a)/(b)≧5 is satisfied. The particulate material A is barium sulfate.

A magnetic carrier includes a magnetic core and a coating resin that covers a surface of the magnetic core. The coating resin includes a resin A and a resin B. A content of the resin A is 1 to 50% by mass, and a content of the resin B is 50 to 99% by mass, with respect to the coating resin. The resin A has a particular unit Y1 and a particular unit Y2, and the resin B contains 0.1% by mass or less of the particular unit Y2. When a mass of the resin A is represented by X, a mass of the unit Y1 is represented by Ma, and a mass of the unit Y2 is represented by Mb, 0.90≤(Ma+Mb)/X≤1.00 and 1.00≤Ma/Mb≤30.0 are satisfied, and also 0≤|SPa−SPb|≤2.0 is satisfied.

A magnetic carrier including: a magnetic core; and a coating resin that coats a surface of the magnetic core, wherein the resin coating layer has a thickness of 50 nm or more, a coating resin, which forms the resin coating layer, contains a resin S having an organosilicon polymer moiety, and when a surface and a position at a depth of 20 nm from the surface of the magnetic carrier are analyzed by X-ray photoelectron spectroscopy, an amount of silicon element as determined by the analysis has a ratio within a specific range at respective positions.

A magnetic carrier, which is suppressed from causing the loss and wear of a magnetic carrier coating resin even when used for a long time period, and achieves a stable image density and a reduction in toner scattering. In the magnetic carrier, the resin coating layer contains a resin A having a fluorine polymer moiety, the resin coating layer has an average thickness of 50 nm or more, a ratio F(x) (atomic %) of a fluorine atom detected at a position at a depth of x nm from a surface of a magnetic carrier particle by X-ray photoelectron spectroscopy satisfies formula (1) and formula (2), and when x represents an integer of 0 or more and 20 or less, F(x) satisfies formula (3):

5.0≤F(0)≤15  (1)

F(20)≤5.0  (2)

|F(x+1)−F(x)|≤7.5  (3).