Abstract: Silica composite particles in which a silica particle surface is sequentially surface-treated with a titanium compound in which an organic group is bonded to a titanium atom through an oxygen atom, and a hydrophobizing agent are provided, in which a titanium content in the silica composite particles measured using fluorescence X-ray is from 0.001% by weight to 10% by weight; a titanium content of a surface layer of the silica composite particles satisfies the following Formula (1); an average particle diameter of the silica composite particles is from 30 nm to 500 nm; and a particle size distribution index of the silica composite particles is from 1.1 to 1.5: 0.6<Y/X<1.8??(1) wherein X represents a titanium content in silica composite particles measured using fluorescence X-ray, and Y represents a titanium content of the silica composite particle surface obtained by XPS measurement.

Abstract: A toner for electrostatic charge image development has toner mother particles including a release agent, a colorant, and a binder resin including a crystalline resin, and an external additive to the toner mother particles including at least metatitanic acid and at least one selected from the group consisting of silicon oxide and fluoropolymer particles, and the addition weight ratio of the metatitanic acid to the at least one selected from the group consisting of silicon oxide and fluoropolymer particles is from 1:0.08 to 1:8.30 is provided.

Abstract: An electrostatic charge image developing toner includes toner particles and silica particles that have a titanium content of from 0.001% by weight to 10% by weight in a surface layer, an average particle diameter of from 30 nm to 500 nm, and a particle size distribution index of from 1.1 to 1.5, and are surface-treated with a titanium compound in which an organic group is bonded to a titanium atom via an oxygen atom, and a hydrophobizing agent in sequence.

Abstract: A method of preparing silica composite particles includes preparing an alkali catalyst solution containing an alkali catalyst at a concentration of from 0.6 mol/L to 0.85 mol/L, in a solvent containing alcohol; and supplying, into the alkali catalyst solution, (i) a mixed solution of tetraalkoxysilane and an organic titanium compound in which an organic group is coupled to a titanium atom through oxygen, and (ii) an alkali catalyst. The mixed solution is supplied at a supply amount of from 0.001 mol/(mol·min) to 0.01 mol/(mol·min) relative to the alcohol, and the alkali catalyst is supplied at a supply amount of from 0.1 mol to 0.4 mol, relative to 1 mol of a total supply amount of the tetraalkoxysilane and the organic titanium compound supplied per one minute.

Abstract: The toner for developing an electrostatic charge image includes toner particles containing a colorant, a binder resin, and a release agent, and an external additive, wherein the external additive contains inorganic particles having fluorine atom-containing oil on the hydrophobization-treated surfaces.

Abstract: Disclosed are silica composite particles in which silica particles are subjected to surface treatment with an aluminum compound in which an organic group is bonded to an aluminum atom through an oxygen atom, and an aluminum surface coverage is from 0.01 atomic % to 30 atomic %, an average particle size is from 30 nm to 500 nm, and a particle size distribution index is from 1.1 to 1.5.

Abstract: An electrostatic charge image developing toner includes toner particles and silica particles that have a titanium content of from 0.001% by weight to 10% by weight in a surface layer, an average particle diameter of from 30 nm to 500 nm, and a particle size distribution index of from 1.1 to 1.5, and are surface-treated with a titanium compound in which an organic group is bonded to a titanium atom via an oxygen atom, and a hydrophobizing agent in sequence.

Abstract: Silica composite particles in which a silica particle surface is sequentially surface-treated with a titanium compound in which an organic group is bonded to a titanium atom through an oxygen atom, and a hydrophobizing agent are provided, in which a titanium content in the silica composite particles measured using fluorescence X-ray is from 0.001% by weight to 10% by weight; a titanium content of a surface layer of the silica composite particles satisfies the following Formula (1); an average particle diameter of the silica composite particles is from 30 nm to 500 nm; and a particle size distribution index of the silica composite particles is from 1.1 to 1.5: 0.6<Y/X<1.8??(1) wherein X represents a titanium content in silica composite particles measured using fluorescence X-ray, and Y represents a titanium content of the silica composite particle surface obtained by XPS measurement.

Abstract: Provided is a method of preparing silica composite particles, including treating silica particles, wherein the treating is for treating the silica particles with a metal compound in which a metal atom binds to an organic group via an oxygen atom, in supercritical carbon dioxide, and the metal atom is selected from a group consisting of Ti, Al, Zr, V, and Mg.

Abstract: An electrostatic charge image developing toner includes toner particles containing a colorant, a binder resin, and a release agent and an external additive, in which the external additive contains inorganic particles which include saturated hydrocarbons having from 9 to 35 carbon atoms on the surfaces thereof.

Abstract: An electrostatic charge image developing toner including toner particles containing a colorant, a binder resin and a release agent; and an external additive, in which the external additive contains inorganic particles having hydrocarbon oil that contains a saturated hydrocarbon having a ring structure on the surfaces thereof.

Abstract: An electrostatic charge image developing toner includes toner particles, and an external additive. The toner particles are (1) prepared by forming aggregated particles by aggregating resin particles in a raw material dispersion in which the resin particles are dispersed, and causing the aggregated particles to coalesce by heating an aggregated particle dispersion in which the aggregated particles are dispersed so as to form the toner particles, or (2) obtained by kneading and pulverizing a material including a binder resin and a release agent, and the external additive is silica particles having an average diameter in the range of 100 nm to 500 nm, an average circularity in the range of 0.5 to 0.85, and an average of a ratio of a circle-equivalent diameter Da obtained by plane image analysis to a maximum height H obtained by 3-D image analysis of greater than 1.5 and less than 1.9.

Abstract: An electrostatic charge image developing toner includes toner particles, and silica composite particles that contain silicon oxide and from 0.001% by weight to 10% by weight of titanium, and have an average particle size of from 30 nm to 500 nm, a particle size distribution index of from 1.10 to 1.50, and an average circularity of from 0.50 to 0.85.

Abstract: Provided is a method of preparing silica composite particles, including treating silica particles, wherein the treating is for treating the silica particles with a metal compound in which a metal atom binds to an organic group via an oxygen atom, in supercritical carbon dioxide, and the metal atom is selected from a group consisting of Ti, Al, Zr, V, and Mg.

Abstract: The toner for developing an electrostatic charge image includes toner particles containing a colorant, a binder resin, and a release agent, and an external additive, wherein the external additive contains inorganic particles having fluorine atom-containing oil on the hydrophobization-treated surfaces.

Abstract: An electrostatic charge image developing toner including toner particles containing a colorant, a binder resin and a release agent; and an external additive, in which the external additive contains inorganic particles having hydrocarbon oil that contains a saturated hydrocarbon having a ring structure on the surfaces thereof.

Abstract: An electrostatic charge image developing toner includes toner particles containing a colorant, a binder resin, and a release agent and an external additive, in which the external additive contains inorganic particles which include saturated hydrocarbons having from 9 to 35 carbon atoms on the surfaces thereof.

Abstract: The invention provides a toner for developing an electrostatic image including toner particles having a shape factor SF1 of 110 or more and including a binder resin, and particles of an external additive that adhere to the toner particles, wherein the particles of the external additive including first particles, and second particles which are adhered to the first particles and have a primary particle size of 0.2 times to 0.5 times as large as that of the first particles, and in an image obtained by observing the particles of the external additive with a microscope, when the projection surface area of the first particle is defined as S1 and the total of the projection surface areas of the second particles which are not hidden by the first particle is defined as S2, S2 being from 0.1 times to 0.5 times as large as S1.

Abstract: An electrostatic charge image developing toner includes toner particles, and an external additive. The toner particles are (1) prepared by forming aggregated particles by aggregating resin particles in a raw material dispersion in which the resin particles are dispersed, and causing the aggregated particles to coalesce by heating an aggregated particle dispersion in which the aggregated particles are dispersed so as to form the toner particles, or (2) obtained by kneading and pulverizing a material including a binder resin and a release agent, and the external additive is silica particles having an average diameter in the range of 100 nm to 500 nm, an average circularity in the range of 0.5 to 0.85, and an average of a ratio of a circle-equivalent diameter Da obtained by plane image analysis to a maximum height H obtained by 3-D image analysis of greater than 1.5 and less than 1.9.

Abstract: An electrostatic charge image developing toner including: toner particles including a binder resin and a colorant; polytetrafluoroethylene particles in which a content of perfluorooctanoic acid and a salt thereof is 0.5 ppm or less; and silica particles in which a content of water is from 0.1% by weight to 10% by weight at an ambient temperature of 20° C. and an ambient humidity of 20%.