A toner including a toner particle containing a binder resin and an external additive, wherein the toner particle contains a polyvalent metal compound, the polyvalent metal compound is at least one selected from the group consisting of aluminum compounds, iron compounds and magnesium compounds, a content of a metal element derived from the polyvalent metal compound in the toner particle is from 0.080 to 20.000 mol/g, the external additive contains an organosilicon polymer particle having a hydroxyl group, a ratio of a number-average particle diameter of the organosilicon polymer particle to a number-average particle diameter of the toner particle is from 0.0160 to 0.0650, and a content of the organosilicon polymer particle is at least 0.10 mass parts per 100.00 mass parts of the toner particle.

An electrophotographic image forming apparatus includes: an electrophotographic photoreceptor; a charger that charges a surface of the electrophotographic photoreceptor; an exposer that exposes the charged electrophotographic photoreceptor; a developer that supplies a toner to the electrophotographic photoreceptor on which an electrostatic latent image is formed; a transferer that transfers a toner image formed on the electrophotographic photoreceptor; and a cleaner that removes a residual toner remaining on a surface of the electrophotographic photoreceptor, wherein the electrophotographic photoreceptor includes an outermost layer, a surface of the outermost layer has a projection structure due to a ridge of the inorganic filler, the toner contains toner base particles and metal oxide particles as an external additive externally added to the toner base particles, 70% or more of the toner base particles are covered with the metal oxide particles as the external additive, and following formulas (1) to (3) are satisfied. $\left[\mathrm{Numerical}\mathrm{formula}1\right]$

An electrostatic-image developing toner includes toner particles, layered compound particles, and a free oil. The mass ratio Ma/Mb of the content Ma of the layered compound particles to the content Mb of the free oil is 0.05 or more and 100 or less.

An electrostatic-image developing toner includes toner particles, aggregated silica particles A treated with an oil, and aggregated or non-aggregated silica particles B rendered hydrophobic with a hydrophobizing agent other than an oil. The average particle size Da of the aggregated silica particles A and the average particle size Db of the silica particles B satisfy DaDb. The electrostatic-image developing toner does not include any external additive other than the aggregated silica particles A or the silica particles B, or the electrostatic-image developing toner includes an external additive other than the aggregated silica particles A or the silica particles B, the other external additive having an average particle size smaller than the average particle size Da.

A decolorizable toner allows for easy distinguishing between a sheet which can be reused and a sheet which is hardly able to be reused from each other. The decolorizable toner includes a color developable compound, a color developing agent, a decolorizing agent, a magnetic material, and a binder resin. The color developable compound is a precursor compound of a dye. The color developing agent is an electron accepting compound which donates a proton to the color developable compound. The decolorizing agent is a compound which inhibits a coloring reaction between the color developable compound and the color developing agent.

A decolorizable toner allows for easy distinguishing between a sheet which can be reused and a sheet which is hardly able to be reused from each other. The decolorizable toner includes a color developable compound, a color developing agent, a decolorizing agent, a magnetic material, and a binder resin. The color developable compound is a precursor compound of a dye. The color developing agent is an electron accepting compound which donates a proton to the color developable compound. The decolorizing agent is a compound which inhibits a coloring reaction between the color developable compound and the color developing agent.

A magnetic toner includes toner particles. The toner particles each include a toner mother particle and an external additive attached to a surface of the toner mother particle. The toner mother particles contain a binder resin and a magnetic powder. The external additive includes resin particles as external additive particles. The resin particles have a blocking rate of no greater than 40% by mass. The resin particles have a number average primary particle diameter of at least 40 nm and no greater than 120 nm. A resin constituting the resin particles is a vinyl resin including repeating units represented by general formulas (1) and (2), and a repeating unit derived from a sulfo group-containing vinyl compound. The content of the repeating unit derived from the sulfo group-containing vinyl compound in the vinyl resin is at least 0.1 mol % and no greater than 3.5 mol %

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A toner includes toner particles including an amorphous polyester resin and a crystalline polyester resin. In the toner, the toner particles include metallic soap, and SPa [(cal/cm.sup.3).sup.1/2] being the SP value (solubility parameter) of the amorphous polyester resin and SPb [(cal/cm.sup.3).sup.1/2] being the SP value of the crystalline polyester resin satisfy the relationship, 0.9SPaSPb1.8. A two-component developer includes the toner and a carrier. An image forming apparatus is used with the two-component developer.

A toner for developing an electrostatic charge image includes toner particles containing a binder resin; and an external additive containing silica particles, in which a coefficient of variation of a Si content is determined by determining the Si content in 0.5 m0.5 m square regions in a surface of each of the toner particles after performing a process of dispersing the toner in water and drying the dispersed toner, and an amount of change between this coefficient of variation of the Si content and a coefficient of variation of a Si content before the process ((coefficient of variation of Si content after process)(coefficient of variation of Si content before process)) is 0.05 or more and 0.60 or less.

A toner for developing an electrostatic charge image includes toner particles containing a binder resin; and an external additive containing silica particles, in which a coefficient of variation of a Si content is determined by determining the Si content in 0.5 m0.5 m square regions in a surface of each of the toner particles after performing a process of dispersing the toner in water and drying the dispersed toner, and an amount of change between this coefficient of variation of the Si content and a coefficient of variation of a Si content before the process ((coefficient of variation of Si content after process)(coefficient of variation of Si content before process)) is 0.05 or more and 0.60 or less.