A toner having excellent development performance, low-temperature fixation, and high-temperature storage stability is provided. An external additive contained in this toner is an organic-inorganic composite fine particle containing an inorganic fine particle embedded in a resin fine particle. The resin fine particle is made from a resin having a melting point of 60? C. or more and 150? C. or less.

Provided is a toner having a toner particle, wherein the toner particle contains a polyester resin and a fatty acid metal salt, the toner contains a tetrahydrofuran-soluble component A with a molecular weight of at least 1,000 and not more than 5,000, as measured by gel permeation chromatography, in an amount of at least 25 mass % and not more than 80 mass %, and a mass ratio of the fatty acid metal salt to the tetrahydrofuran-soluble component A is at least 0.003 and not more than 0.060.

A toner includes toner particles containing a binder resin, a colorant, and inorganic fine particles, in which in a depth profile of an element distribution in a depth region from the outermost surface of a particle to a depth of 500 nm the depth profile being obtained by an element analysis performed by X-ray photoelectron spectroscopy using the toner as a sample, two or more minimum points of a concentration of a carbon element in the depth region exist, a concentration of an inorganic element becomes a maximum value at a depth position corresponding to each of the minimum points, and the inorganic element is an element derived from the inorganic fine particle.

Mixtures are disclosed containing a plurality of charged pigment particles and one or more charge control agents. At least one of the charge control agents has a chemical structure that includes a cationic head group, such as an ammonium cation or an iminium compound, and a non-ionic, polar functional group, other than an acyclic secondary amide group. The mixtures are useful as dispersions for forming electrophoretic media that may be incorporated into electrophoretic displays. Alternatively, the dispersions may be useful for forming electrophotographic toners and dispersions for other printing applications.

To provide a toner that is less likely to cause image defects due to the detachment of the silica aggregated particle even when having been used for a long period of time in a low-temperature and low-humidity environment. The toner includes: a toner particle containing a binder resin; and a silica aggregated particle, wherein, in TOF-SIMS measurement of the toner particle, a fragment peak derived from a boron atom and a fragment peak derived from a boron-oxygen structure are detected; the silica aggregated particle is an aggregated particle of silica fine particles having a primary particle size based on number of from 20 to 75 nm, a maximum Feret's diameter of the silica aggregated particle is from 110 to 500 nm, and an aspect ratio thereof is from 1.50 to 4.00.

The present invention provides a toner which can form a stable image even in a low print intermittent mode under a low-temperature and low-humidity environment, while having excellent charge rising property. A toner includes a toner particle and a silica fine particle A, wherein (I) in TOF-SIMS measurement of the toner particle, a fragment peak derived from a boron atom and a fragment peak derived from a BO structure are detected, and the toner contains dodecylbenzenesulfonic acid or a dodecylbenzenesulfonate; (II) in TOF-SIMS measurement of the silica fine particle A, a fragment ion is observed which corresponds to a dimethylsiloxane structure; when 2.00 g of the silica fine particle is dispersed in a mixed liquid of 25.0 g of ethanol and 75.0 g of an aqueous solution of 20% by mass of NaCl, and the dispersion is subjected to a titration operation which uses sodium hydroxide, Sn defined by Sn=[(a?b)?c?NA]/(d?e) satisfies 0.10?Sn?0.80.

An electrostatic charge image developing toner set includes an electrostatic charge image developing black toner that includes black toner particles including a black colorant, a binder resin, and a release agent, and inorganic particles containing an oil; and an electrostatic charge image developing color toner that includes color toner particles including a color colorant, a binder resin, and a release agent, and inorganic particles containing an oil, wherein a proportion of the release agent exposed to a surface of the color toner particles is greater than a proportion of the release agent exposed to a surface of the black toner particles.

A toner comprising a toner particle containing a binder resin, a wax, and inorganic fine particles, wherein the binder resin contains a crystalline polyester resin and an amorphous polyester resin, and, in a cross section of the toner particle, when Sc represents an area taken up by the crystalline polyester resin and S1 represents an area taken up by the inorganic fine particles that are present in the crystalline polyester resin portion, Sc and S1 satisfy the relationship S1/Sc0.2.

A toner includes an external additive particle that is a complex oxide containing a titanium dioxide (TiO.sub.2) and a silicon dioxide (SiO.sub.2). A detection amount of titanium (Ti) detected through an elementary analysis based on energy-dispersive X-ray spectrometry is equal to or higher than about 0.590 percent by weight and equal to or lower than about 0.967 percent by weight.

An electrophotographic toner set, an image forming apparatus, and an image forming method include a developer toner and a replenishment toner. The developer toner and the replenishment toner each include toner particles, and silica particles and titania particles provided on the surfaces of the toner particles. The silica particles have a BET specific surface area of 15 to 95 m.sup.2/g and are surface-treated with a silicone oil. The relationship between the content of the silica particles of the developer toner and the content of the silica particles of the replenishment toner, and the relationship between the content of the titania particles of the developer toner and the content of the titania particles of the replenishment toner each have particular values.