The toner comprises a toner particle that comprises a binder resin-containing core particle and a thermosetting resin-containing shell on the surface of the core particle, wherein the binder resin includes at least one of (i) a vinyl resin and a polyester resin and (ii) a hybrid resin in which a vinyl resin and a polyester resin are bonded; the polyester resin comprises in a main chain thereof a cyclic structure, and the content of the polyester resin in the tetrahydrofuran-soluble matter of the toner is at least 51 mass%; the vinyl resin comprises a prescribed monomer unit; the thermosetting resin is at least one resin selected from melamine resins, urea resins, and oxazoline group-bearing vinyl resins; and the average circularity of the toner is in a prescribed range.

A toner for electrostatic charge image development includes toner particles, the toner particles containing a binder resin containing a vinyl resin and a release agent containing an ester wax, in which in sections of the toner particles, a number average of equivalent circle diameters of sections of domains of the release agent is 0.10 μm or more and 1.5 μm or less, and a standard deviation of the equivalent circle diameters is more than 0.05 and 0.5 or less.

Provided is a toner including toner particles. Each of the toner particles includes a toner base particle including a binder resin and a release agent. The toner particles have an average circularity of 0.974 or greater and 0.985 or less. An arithmetic mean height Sa of surfaces of the toner particles is 45 nm or greater. The toner particles have a BET specific surface area of 1.3 m.sup.2/g or greater and 2.5 m.sup.2/g or less.

[Object] An object of the invention is to provide a toner that can both achieve a higher level of low temperature fixability and suppression of the toner scattering.

[Means of Achieving the Object]

The disclosure is to provide a toner, including base-particles, and an external-additive, wherein a glass-transition temperature obtained from a DSC-curve at a second-warming of a THF-insoluble component is −50° C. or higher and 10° C. or lower, wherein an average circularity of the toner is 0.975 or more and 0.985 or lower, wherein the toner satisfies the following formula:

1.5≤Bt−0.025−Ct≤3.0, wherein the Bt [m.sup.2/g] is a BET-specific-surface area of the toner-particles, and the Ct [%] is a coverage by the external-additive, and, at least a portion of a surface of the external-additive is coated with either an oxide of a metallic element, a hydroxide of the metallic element, or both.

Provided are a process cartridge and an electrophotographic apparatus each capable of suppressing an image defect (coarseness in a halftone image) caused by toner scattering in association with a charging failure that occurs when the process speed of the electrophotographic apparatus is further increased. The process cartridge includes: an electrophotographic photosensitive member; and a developing unit, which includes a toner storing portion that stores a toner, and which supplies the toner to a surface of the electrophotographic photosensitive member. The electrophotographic photosensitive member includes a surface protective layer containing an electroconductive particle in an appropriate amount, and the volume resistivity of the surface protective layer is controlled. As the toner, there is used a toner in which an organosilicon polymer is present on the surface of a toner particle, a silanol group is present in part of the organosilicon polymer, and the amount of the silanol group is controlled.

A toner includes: toner base particles each containing a binder resin; and resin particles on a surface of each of the toner base particles. A glass transition temperature (Tg) of the toner at the first heating in differential scanning calorimetry (DSC) is 20° C. or higher and 50° C. or lower. A glass transition temperature of a tetrahydrofuran (THF)-insoluble component of the toner at the first heating in DSC is −40° C. or higher and 10° C. or lower. An average circularity of the toner is 0.970 or more and 0.985 or less. A standard deviation of the average circularity is 0.020 or less.

An object of the present invention is to provide an electrostatic latent image developing toner containing: a binder resin; and a releasing agent, wherein the binder resin contains a crystalline polyester resin; an endothermic peak top temperature of the electrostatic latent image developing toner is 70° C. or more measured with differential scanning calorimetry (DSC) in a heating-up period of the toner; and a heat value ΔH.sub.c(L) is 15% or less with respect to a heat value ΔH.sub.c, wherein the heat value ΔH.sub.c(L) is a heat value in the range of (an exothermic peak top temperature r.sub.c−7° C.) or less; and the heat value ΔH.sub.c is a heat value of the total exothermic peak measured with DSC in a heating-down period of the toner.

Provided is a toner that achieves low-temperature fixability, storability and charging performance all at a high level, in which a toner containing a crystalline resin and an amorphous resin, wherein a standard deviation of hydrogen nuclear relaxation times (HT1ρ-C) of the toner as measured by solid-state .sup.13C-NMR is from 0.0 to 5.0, and a hydrogen nuclear relaxation time (HT1ρ-C1) of a .sup.13C peak with the longest relaxation time out of the hydrogen nuclear relaxation times (HT1ρ-C) and a hydrogen nuclear relaxation time (HT1ρ-A1) of a .sup.13C peak with the shortest relaxation time out of the hydrogen nuclear relaxation times (HT1ρ-A) satisfy 3.0≦{(HT1ρ-C1)/(HT1ρ-A1)}≦6.0.

There is provided an electrostatic image-developing toner containing a binder resin, a coloring agent and a release agent having a melting temperature of 85° C. to 120° C., the toner having a sea-island structure involving a sea part containing the binder resin and an island part containing the release agent, wherein a mode value of the distribution of the eccentricity degree B of the release agent-containing island part, represented by the specific formula, is from 0.75 to 1.00 and a skewness of the distribution of the eccentricity degree B is from −1.30 to −0.50.

An object of the present invention is to provide a toner that exhibits high levels of the low-temperature fixability, storability, and charging performance all at the same time. The toner of the present invention is a toner that has a toner particle comprising a crystalline resin and an amorphous resin, the toner being characterized in that the toner satisfies 0.00≦(Wt2/Wt1)≦0.50; the toner particle has a matrix-domain structure in which domains of the crystalline resin are present in a matrix of the amorphous resin; at least 90 number % of the crystalline resin domains are domains with a diameter from 0.05 μm to 0.50 μm; and SF1 for the crystalline resin domains is from 100 to 130.