An electrophotographic photoreceptor includes a conductive substrate, an undercoat layer on the conductive substrate, a charge generation layer on the undercoat layer, a charge transport layer on the charge generation layer, and an inorganic protection layer on the charge transport layer, in which the charge transport layer contains a binder resin and a charge transport material, and, when impedance of the charge transport layer is measured, a ratio (C.sub.1 Hz/C.sub.10 Hz) of an electrostatic capacitance C.sub.1 Hz at 1 Hz to an electrostatic capacitance C.sub.10 Hz at 10 Hz is 1.1 or less.

An electrophotographic photosensitive member including a surface layer, wherein the surface layer comprises a fluorine atom-containing resin particle, a binder material, and a polymer having a specific structural unit.

Provided is an electrophotographic photosensitive member including a support and a surface layer, wherein the surface layer contains a copolymer of a composition containing a specific hole transporting compound and a specific compound.

There is provided a process cartridge detachably attachable to a main body of an electrophotographic apparatus, the process cartridge including an electrophotographic photosensitive member and a charging member, wherein an outer surface of the charging member is composed of at least a matrix and at least a part of domains, a volume resistivity of the matrix is 1.0×10.sup.5 times or more of a volume resistivity of the domain, an average value Sd of circle equivalent diameters of the domains observed on the outer surface of the charging member is in a predetermined range, the electrophotographic photosensitive member contains a support, a photosensitive layer, and a protective layer in this order and when a surface roughness of the protective layer is measured, each of a protruding valley portion Rvk, a load length ratio Mr2, and Sd/Rvk is in a predetermined range.

Provided is an image forming method using a toner for developing an electrostatic charge image and an electrophotographic photoreceptor, and containing at least a charging step, an exposing step, a developing step and a transferring step, wherein the electrophotographic photoreceptor has a photosensitive layer, and the photosensitive layer contains a triphenylamine derivative having a specific structure as a charge transport material, and the toner for developing an electrostatic charge image contains at least titanic acid compound particles as an external additive.

Provided is an image forming method using a toner for developing an electrostatic charge image and an electrophotographic photoreceptor, and containing at least a charging step, an exposing step, a developing step and a transferring step, wherein the electrophotographic photoreceptor has a photosensitive layer, and the photosensitive layer contains a triphenylamine derivative having a specific structure as a charge transport material, and the toner for developing an electrostatic charge image contains at least titanic acid compound particles as an external additive.

Provided are an electrophotographic apparatus and a process cartridge each capable of suppressing the occurrence of a black spot (white background contamination) in an output image under a low-temperature and low-humidity environment. The electrophotographic apparatus includes: an electrophotographic photosensitive member including a support, a photosensitive layer, and a protective layer in the stated order; an exposing device; a developing device; and a cleaning device, wherein the protective layer has a triarylamine structure and a specific structure at a ratio in a specific range, and a toner contains toner particles each containing at least a resin, and an external additive. The toner has a volume-average particle diameter of 7 μm or more. The external additive contains a compound containing a titanium atom. The ratio of the mass of the compound containing a titanium atom to the total mass of the toner is 0.6 mass % or more.

The present disclosure provides an electrophotographic photosensitive member that has mechanical durability, and can achieve both of suppression of an image flow and adequate electrical characteristics. In the electrophotographic photosensitive member having a support and a photosensitive layer provided on the support, a surface layer of the electrophotographic photosensitive member contains a copolymerized product of a composition containing a hole transporting compound represented by the following formula (1) and a compound represented by the following formula (3): ##STR00001##

There is provided a process cartridge detachably attachable to a main body of an electrophotographic apparatus, the process cartridge including an electrophotographic photosensitive member and a charging member, wherein an outer surface of the charging member is composed of at least a matrix and at least a part of domains, a volume resistivity of the matrix is 1.010.sup.5 times or more of a volume resistivity of the domain, an average value Sd of circle equivalent diameters of the domains observed on the outer surface of the charging member is in a predetermined range, the electrophotographic photosensitive member contains a support, a photosensitive layer, and a protective layer in this order and when a surface roughness of the protective layer is measured, each of a protruding valley portion Rvk, a load length ratio Mr2, and Sd/Rvk is in a predetermined range.

Provided is an electrophotographic photosensitive member having a satisfactory suppressing effect on image smearing. The electrophotographic photosensitive member includes: a support; a photosensitive layer; and a surface layer, the surface layer containing at least one of melamine resin-containing particles and acrylic resin-containing particles, and a polymerized product of a composition containing a charge-transporting compound having a polymerizable functional group; and a compound represented by formula (1):

##STR00001##