A toner which is less likely to cause toner leakage and which is less likely to cause aggregation after being left to stand under a high temperature condition. A toner for developing electrostatic images, comprising colored resin particles comprising a binder resin and a colorant, and an external additive, wherein a conditioned bulk density obtained by a powder flowability analyzing device is from 0.525 g/mL to 0.565 g/mL.

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 comprising a toner particle, the toner particle comprising a binder resin, the binder resin comprises a crystalline resin A, the crystalline resin A comprises a monomer unit (a) having specific structure, when, in measurement of viscoelasticity of the toner, T1 ( C.) represents a temperature at which a storage elastic modulus G of the toner is 1.010.sup.7 Pa, tan (T1) represents a ratio (tan ) of a loss elastic modulus G of the toner to the storage elastic modulus G of the toner at the temperature T1 ( C.), and tan (T1-10) represents tan at a temperature T1-10 ( C.), the T1, the tan (T1), and the tan (T1-10) satisfy specific relationship, and the toner particle comprises a linear fatty acid metal salt having a valency of 2 or more.

Provided is a process cartridge detachably attachable to a main body of an electrophotographic apparatus, the process cartridge including: a developing unit including a toner; and an electrophotographic photosensitive member, wherein the toner includes a toner particle, the toner particle has a surface containing a polyvalent acid metal salt particle, and a surface layer of the electrophotographic photosensitive member contains at least one metal oxide particle among an aluminum oxide particle, a silicon dioxide particle, and a tin oxide particle.

A toner comprising a toner particle, wherein the toner particle includes a binder resin, where a volume resistivity .Math.cm of an unfixed solid image on a recording material on which the solid image has been formed using the toner at a toner laid-on level of 0.4 mg/cm.sup.2 is denoted by Tv, and a volume resistivity .Math.cm of the solid image after fixing by applying heat and pressure to the recording material is denoted by Fv, Tv/Fv8 is satisfied.

Provided are a process cartridge and an electrophotographic apparatus each of which is reduced in fogging for reducing a toner consumption. Specifically, provided is a process cartridge, which is removably mounted onto a main body of an electrophotographic apparatus, the process cartridge including: a developing unit containing a toner; and an electrophotographic photosensitive member, wherein the toner is a toner including a toner particle, and has a polyvalent acid metal salt on at least part of a surface of the toner particle, wherein the polyvalent acid metal salt includes at least one kind of metal element selected from metal elements belonging to from Group 3 to Group 13, and wherein a surface layer of the electrophotographic photosensitive member contains a resin including a siloxane segment.

The present disclosure provides a process cartridge and an electrophotographic apparatus in which fogging is reduced so as to reduce an amount of toner consumed. A process cartridge configured to be detachably attachable to a main body of an electrophotographic apparatus includes a developing unit containing a toner, and an electrophotographic photosensitive member, wherein the toner is a toner that has a toner particle, and has a metal salt of a polyvalent acid at least on a part of a surface of the toner particle; wherein the metal salt of the polyvalent acid includes at least one kind of metal element selected from metal elements belonging to from Group 3 to Group 13, and a surface layer of the electrophotographic photosensitive member contains an acrylic resin or a methacrylic resin.

A toner comprising a toner particle, wherein the toner particle includes a toner base particle containing a binder resin and includes a protruded portion on a surface of the toner base particle; the protruded portion comprises an organosilicon polymer and a polyhydric acid metal salt; and the polyhydric acid metal salt is present on a surface of the protruded portion.

A metal compound includes a metal and at least two aromatic hydroxycarboxylic acid structures. Each aromatic hydroxycarboxylic acid structure includes an aromatic moiety having a hydroxyl substituent and a carboxylic acid substituent, which cooperatively bond the aromatic moiety to the metal via at least one of ionic bond, covalent bond and coordinate bond. Each aromatic hydroxycarboxylic acid structure is bonded to a polymer segment.

A toner comprising: a toner particle including a binder resin; and an external additive, wherein the external additive includes an external additive A which is silica fine particles and an external additive B which is a fatty acid metal salt, the external additive A has a specific particle diameter, a coverage ratio of a surface of the toner particle with the external additive A is from 60% to 80%, and where an average theoretical surface area obtained from a number average particle diameter, a particle size distribution and a true density of the toner particle is denoted by C (m.sup.2/g), an amount of the external additive B is denoted by D (parts by mass) and a coverage ratio of the surface of the toner particle with the external additive B is denoted by E (%), following formulas are satisfied:

0.05D/C2.00

E/(D/C)50.0.