An image forming method uses an electrophotographic photoreceptor and a toner for developing an electrostatic charge image. The image forming method has a charging step, an exposure step, a developing step, a transfer step and a cleaning step, wherein the charging step uses a contact charging device; the photoreceptor has a universal hardness value (HU) of 170 N/mm.sup.2 or more, and an elastic deformation ratio of 40% or more when a Vickers indenter is used in a predetermined environment and pushed by a maximum load of 2 mN. The toner for developing an electrostatic charge image contains toner base particles of a core-shell structure having a shell layer of 10% by mass or less with respect to a mass of a toner base particle on an outside of a resin constituting a core particle, and a solubility parameter value (SPs) of a resin constituting the shell layer is 10.75 or less.

The toner has a toner matrix particle containing a crystalline polyester resin. Associated silica including two or more of primary particles is present on the surface of the toner matrix particle. The coverage with associated silica onto the toner matrix particle is 1% or more to 30% or less, and the adherence strength of associated silica to the toner matrix particle is 20% or more to 90% or less.

Provided is an electrophotographic photosensitive drum that achieves both of a reduction in torque of the electrophotographic photosensitive drum at the time of its cleaning and an improvement in image transferability. The electrophotographic photosensitive drum includes: a support; and a photosensitive layer arranged on the support, the electrophotographic photosensitive drum having arranged on an outer surface thereof at least two structure groups having different appearance periods, wherein when, out of the two structure groups, a group including structures having a smaller appearance period is defined as a first structure group, and a group including structures having a larger appearance period is defined as a second structure group, a height of the first structure group is lower than a height of the second structure group.

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, in which when average local potential differences of calculated lengths in the electrophotographic photosensitive member is calculated based on a specific method, a maximum value of the average local potential difference is 2 V or more, the charging member includes a support and an electro-conductive layer, the electro-conductive layer has a matrix and domains dispersed in the matrix, a volume resistivity ρM of the matrix is at least 1.00×10.sup.5 times a volume resistivity ρD of the domain, and a specific calculated length S.sub.CP [μm] and a specific value relating a distance between the domains D.sub.ms [μm] satisfy S.sub.CP≥3×D.sub.ms.

An electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer disposed on the conductive substrate. An outermost surface layer of the electrophotographic photoreceptor contains a fluorine-containing resin particle and a fluorine-based graft polymer having a fluorinated alkyl group. A ratio of an amount of a fluorine-based graft polymer separated from the fluorine-containing resin particle to a total amount of the fluorine-based graft polymer in the outermost surface layer is 15% or less.

Disclosed is a cylindrical electrophotographic photosensitive member having a region A along an outer surface and a region B along the outer surface. In this electrophotographic photosensitive member, the region A is located on an end side in an axial direction of the electrophotographic photosensitive member relative to the region B, the region A has a specific groove provided on the outer surface of the electrophotographic photosensitive member, an area ratio a1 of the groove is 65% to 100%, the region B has specific concave portions provided on the outer surface of the electrophotographic photosensitive member, and an area ratio a2 of the concave portion is 5% to 65%.

An electrophotographic photoconductor in which a surface layer of a photosensitive layer or an overcoat layer has a glass transition temperature Tg greater than 100° C. and a hardness greater than 0.22 GPa. An electrophotographic cartridge and an electrophotographic imaging apparatus include the electrophotographic photoconductor. Flipping-over of a cleaning blade that comes into contact with the electrophotographic photoconductor may be effectively suppressed or prevented, the degree of freedom in terms of cleaning blade selection may be increased, and the possibility of causing high-frequency noise due to friction may be reduced.

A dispersant-attached polytetrafluoroethylene particle includes a polytetrafluoroethylene particle and a dispersant that attaches to a surface of the polytetrafluoroethylene particle and contains a fluorine atom. The particle size distribution index [D.sub.50-D.sub.10] is less than 50 nm and the electrical conductivity is 7 μS/cm or less.

An electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer disposed on the conductive substrate. An outermost surface layer of the electrophotographic photoreceptor contains fluorine-containing resin particles and a fluorine-containing graft polymer having a fluorinated alkyl group. In an infrared absorption spectrum of the fluorine-containing graft polymer, a ratio of a peak area in a wavenumber range of from 1,020 cm.sup.−1 to 1,308 cm.sup.−1 to a peak area in a wavenumber range of from 1,673 cm.sup.−1 to 1,779 cm.sup.−1 is 2.7 or more and 4.8 or less.

An electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer on the conductive substrate. The outermost surface layer of the electrophotographic photoreceptor contains fluorine-containing resin particles, a fluorine graft polymer, and an acidic compound having an acid dissociation constant (pKa) of 3 or less in water at 25° C. The amount of the acidic compound relative to the outermost surface layer is 100 ppm or more and 10000 ppm or less.