An electrostatic charge image developing toner includes a toner particle, a polishing agent particle, and a fatty acid metal salt particle, wherein a rate of the fatty acid metal salt particles strongly attached to the surface of the toner particles is equal to or greater than 50% by number with respect to the fatty acid metal salt particles attached to the surface of the toner particles.

An electrostatic charge image developing toner includes toner particles, polishing agent particles which have a number particle size distribution having two peaks, and fatty acid metal salt particles which have a number particle size distribution having one peak, wherein the toner satisfies relationships expressed by expressions: (1) Da≦0.5×Dt, (2) Dc≦0.5×Dt and (3) Dt≦Db, wherein Da represents a particle diameter of a small-diameter-side peak in the two peaks of the number particle size distribution of the polishing agent particles, Db represents a particle diameter of a large-diameter-side peak in the two peaks of the number particle size distribution of the polishing agent particles, Dc represents a particle diameter of a peak of the number particle size distribution of the fatty acid metal salt particles, and Dt represents a volume average particle diameter of the toner particles.

The present invention is to provide a toner for developing electrostatic images, which has an excellent balance between low-temperature fixability and heat-resistant shelf stability, which has good toner conveyance amount stability and printing durability, and which has less occurrence of fog in a high temperature and high humidity environment. Disclosed is a toner for developing electrostatic images, comprising colored resin particles containing a binder resin and a colorant, and an external additive, wherein the toner comprises, as the external additive, fine silica particles in an amount of 0.5 to 3.0 parts by mass with respect to 100 parts by mass of the colored resin particles, the fine silica particles having a hydrophobicity of 15 to 49% that is determined after a high-temperature and high-humidity incubation.

An electrostatic charge image developing toner includes toner particles and an external additive that includes silica particles having a compression aggregation degree of 60% to 95% and a particle compression ratio of 0.20 to 0.40 and fatty acid metal salt particles.

An electrostatic charge image developing toner includes toner particles containing a binder resin and a release agent and an external additive containing fatty acid metal salt particles and abrasive particles, wherein a ratio (B/A) of an isolation amount B of the abrasive particles isolated from the toner particles after an ultrasonic isolation treatment to an isolation amount A of the fatty acid metal salt particles isolated from the toner particles after the ultrasonic isolation treatment is from 0.3 to 2.0.

A toner having a toner particle which contains a binder resin, a fatty acid metal salt, and a resin having an ionic functional group, in which the fatty acid metal salt is a fatty acid metal salt of a polyvalent metal with valency of 2 or higher and a fatty acid with carbon atom number of at least 8 and not more than 28, and the acid dissociation constant pKa of the resin having an ionic functional group is at least 6.0 and not more than 9.0.

A toner including a toner particle including a binder resin, wherein fine particles A and B are present on a surface of the toner particle; the fine particles A are a fatty acid metal salt; the fine particles B have a specific volume resistivity; an average theoretical surface area of the toner particle, an amount of the fine particles A, and a coverage ratio of the toner particle surface by the fine particles A satisfy a specific relationship; the amount of the fine particles B is in a specific range; and a proportion F of an area occupied by a part of the fine particles B embedded in a surface vicinity region of the toner in a total area occupied by the fine particles B present in a cross section of one particle of the toner is 50% by area or more.

Pressure-responsive particles include pressure-responsive base particles and resin particles, in which the pressure-responsive base particles contain a styrene-based resin that contains styrene and other vinyl monomers as polymerization components and a (meth)acrylic acid ester-based resin that contains at least two kinds of (meth)acrylic acid esters as polymerization components, a ratio of a mass of the (meth)acrylic acid esters to a total mass of polymerization components is 90% by mass or more in the (meth)acrylic acid ester-based resin, the pressure-responsive particles have at least two glass transition temperatures, a difference between a lowest glass transition temperature and a highest glass transition temperature is 30° C. or higher, and a ratio of a mass of the resin particles to a total mass of the pressure-responsive particles is 0.05% by mass or more and 2.0% by mass or less.

A toner having high rub resistance is provided. A toner including a toner particle containing a binder resin and a calcium carbonate particle, wherein in X-ray diffractometry of the toner particle by CuKα radiation, when the Bragg angle is defined as θ, (i) the calcium carbonate particle has peaks at 2θ of 26.5°±0.5° and 29.5°±0.5°, (ii) a crystallite diameter of crystals thereof attributed to 2θ=29.5°±0.5° is 10 nm or more and 45 nm or less, and (iii) the ratio (a/b) of a peak intensity “a” at 2θ=26.5°±0.5° to a peak intensity “b” at 20θ=29.5°±0.5° is 0.15 or more and 0.24 or less.

A toner composition having improved toner usage efficiency, wherein toner particles having an average size range of 1-25 μm may be mixed with an extra particulate additive package including a first small silica surface treated with both a silane and an aminosilane having a primary particle size of about 5 nm-20 nm, a second fumed silica having a primary particle size of 30 nm-60 nm, a third silica having a primary particle size of about 70 nm-120 nm, an electro-conductive titania having a primary particle size of 30 nm-60 nm and an acicular titania having a size of about 1.6 μm to 1.7 μm in length and about 130 nm in diameter. An alternative embodiment of the extra particulate additive package does not include a third silica having a primary particle size of about 70 nm-120 nm.