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 Zr localized in the surface thereof is used.

A toner includes toner particles. The toner particles each include a core, a shell layer, and an external additive. The core contains a first thermoplastic resin as a binder resin. The shell layer partially covers a surface of the core. The external additive is attached to regions of the surface of the core that are not covered with the shell layer. The external additive includes external additive particles. The external additive particles protrude outward in radial directions of the core further than a surface of the shell layer. At least part of surfaces of the external additive particles is exposed from the shell layer. The shell layer contains a second thermoplastic resin or a thermosetting resin. The second thermoplastic resin has a higher softening point than the core. The shell layer has a thickness of at least 5 nm.

A toner includes toner particles. The toner particles each include a core, a shell layer, and an external additive. The core contains a first thermoplastic resin as a binder resin. The shell layer partially covers a surface of the core. The external additive is attached to regions of the surface of the core that are not covered with the shell layer. The external additive includes external additive particles. The external additive particles protrude outward in radial directions of the core further than a surface of the shell layer. At least part of surfaces of the external additive particles is exposed from the shell layer. The shell layer contains a second thermoplastic resin or a thermosetting resin. The second thermoplastic resin has a higher softening point than the core. The shell layer has a thickness of at least 5 nm.

Provided are constituent particles containing a water-soluble material with high flowability in the form of powder, the constituent particles being capable of forming a support member that can be removed with a water-containing solvent in a process for producing a three-dimensional object. The constituent particles used for the production of a three-dimensional object each include a core and a shell that covers at least part of a surface of the core, the core containing a water-soluble material most abundantly, and a material contained in the shell most abundantly having a lower water solubility than the water-soluble material contained in the core.

A toner includes a plurality of toner particles each including a core and a shell layer entirely covering a surface of the core. The core contains a foamable polymer having a foamable group that is foamable through heating. A first foaming amount is at least 7 mL. The first foaming amount is an amount of gas collected over water during a period from when heating of the toner up to 120 C. is started at 30 C. to when a temperature of the toner has been kept at 120 C. for 30 minutes after the heating. A second foaming amount is at least 6 mL. The second foaming amount is an amount of gas collected over water during a period from when the heating is started at 30 C. to when the temperature of the toner reaches 0 C. through cooling after the liquid has been kept at 120 C. for 30 minutes.

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 Zr localized in the surface thereof is used.

A toner includes a plurality of toner particles each including a core and a shell layer entirely covering a surface of the core. The core contains a foamable polymer having a foamable group that is foamable through heating. A first foaming amount is at least 7 mL. The first foaming amount is an amount of gas collected over water during a period from when heating of the toner up to 120 C. is started at 30 C. to when a temperature of the toner has been kept at 120 C. for 30 minutes after the heating. A second foaming amount is at least 6 mL. The second foaming amount is an amount of gas collected over water during a period from when the heating is started at 30 C. to when the temperature of the toner reaches 0 C. through cooling after the liquid has been kept at 120 C. for 30 minutes.

In accordance with an embodiment, a toner particle comprises two or more glass transition temperatures. Wherein, a first glass transition temperature is within a range from 5 degrees centigrade to 20 degrees centigrade and a second glass transition temperature is within a range from 50 degrees centigrade to 65 degrees centigrade.

A method for producing core shell toner for electrophotography according to one embodiment, includes surface treating the outer surface of a core shell toner particle with a alkoxysilane hydrocarbon or combination of different alkoxysilane hydrocarbons using a hydrolytic deposition process after the core shell toner particle is fully formed. This method results in the bonding of the alkoxysilane hydrocarbon or combination of different alkoxysilane hydrocarbons to the outer surface of the core shell toner particle. In an alternative method, the outer surface of the toner is surface treated with the alkoxysilane hydrocarbon solution and then fused to form toner particles. The alkoxysilane hydrocarbon surface treated core shell toner also can be mixed with magnetic carrier beads to form a developer mix to be used in a dual component development electrophotographic printer.

An electrostatic latent image developing toner includes a plurality of toner particle each including a toner mother particle and silica particles attached to a surface of the toner mother particle. The toner mother particle includes a toner core and a shell layer. The shell layer includes a first domain substantially formed from a first resin and a second domain substantially formed from a second resin. Both the first resin and the silica particles have higher positive chargeability than the second resin. A shell coverage is at least 40% and no greater than 90%. The toner particles each have an average value of surface potentials measured using a scanning probe microscope of at least +50 mV and no greater than +350 mV and a standard deviation thereof of no greater than 120 mV.