A conductive support is formed of a bottomless hollow cylindrical member being made of metal and having a thickness t of equal to or less than 0.5 mm, the conductive support including: a chamfer portion on an outer peripheral surface side of at least one end of the conductive support over an entire circumferential direction, wherein the chamfer portion has a chamfer angle a of equal to or greater than 10 and less than 30 with respect to the outer peripheral surface, and a chamfer width b equal to or greater than 0.05 mm in an end surface, and wherein an end surface width c is equal to or greater than 0.1 mm in the end surface including the chamfer portion.

Disclosed herein is an electrophotographic photosensitive member in which leakage hardly occurs even in the case of using a layer containing metal oxide particles as an electrically conductive layer in the electrophotographic photosensitive member, and which is compatible with definition in output images, the electrophotographic photosensitive member sequentially including: a support, an electrically conductive layer, and a photosensitive layer, the electrically conductive layer containing a binder material and particles represented by General Formula (1).

Nb.sub.2.00O.sub.5.00-XN.sub.Y (1)

(In Formula (1), Nb is a niobium atom, O is an oxygen atom, N is a nitrogen atom, and 0.00<Y<X4.00.)

Provided is an electrophotographic photosensitive member including in this order: a support; an undercoat layer; and a photosensitive layer, wherein the undercoat layer contains a polymer having a structural unit represented by the following formula (1).

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A novel compound having electron-transporting property which dissolves sufficiently in an organic solvent is provided.

Provided is an electrophotographic photosensitive member including a support and a photosensitive layer, wherein the photosensitive layer contains two kinds of benzimidazoperylene compounds as electron transporting substances.

A conductive support is formed of a bottomless hollow cylindrical member being made of metal and having a thickness t of equal to or less than 0.5 mm, the conductive support including: a chamfer portion on an outer peripheral surface side of at least one end of the conductive support over an entire circumferential direction, wherein the chamfer portion has a chamfer angle a of equal to or greater than. 10 and less than 30 with respect to the outer peripheral surface, and a chamfer width b equal to or greater than 0.05 mm in an end surface, and wherein as end surface width c is equal to or greater than 0.1 mm in the end surface including the chamfer portion.

Provided is a process cartridge being detachably attachable onto a main body of an electrophotographic apparatus. The process cartridge includes an electrophotographic photosensitive member, a developing roller, and a toner-supplying roller. The developing roller and the toner-supplying roller are rotated so as to satisfy a particular velocity ratio so that the surface of the developing roller and the surface of the toner-supplying roller are opposite to each other at a contact position therebetween. The surface of the developing roller is a surface of an elastic layer, and the toner-supplying roller includes a shaft body and a resin layer formed on an outer peripheral surface of the shaft body. The electrophotographic photosensitive member includes a surface layer containing a polyarylate resin including a structural unit represented by the following formula (A1) and a structural unit represented by the following formula (A2).

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An image forming method includes forming an image with a toner using a photoconductor in which an intermediate layer and a photosensitive layer including a charge generating layer and a charge transport layer are formed overlying an electroconductive substrate, wherein the ionization potential of the surface of the photoconductor and the ionization potential of the surface of the toner satisfy the following relations 1 and 2,

|Ip(the surface of the photoconductor)Ip(the surface of the toner)|0.18 (eV) Relation 1

5.45 (eV)Ip(the surface of the photoconductor)5.53 (eV) Relation 2 where Ip (the surface of the photoconductor) represents the ionization potential of the surface of the photoconductor and Ip (the surface of the toner) represents the ionization potential of the surface of the toner.

An electrophotographic photoreceptor includes a conductive substrate, a photosensitive layer provided on or above the conductive substrate and containing inorganic oxide particles, and an inorganic protective layer provided on the photosensitive layer. In a particle size distribution of the inorganic oxide particles obtained through cross-sectional observation of the photosensitive layer, the highest peak for small-diameter particles A is present in the range of 20 nm to 50 nm, and the highest peak for large-diameter particles is present in the range of 80 nm to 400 nm, with the threshold particle diameter for the small-diameter particles A and the large-diameter particles being 60 nm, and the relationship between the particle diameter dA at the highest peak for the small-diameter particles A and the particle diameter dB at the highest peak for the large-diameter particles satisfies formula (A1) below:

[00001]$\begin{array}{cc}\mathrm{dB}/\mathrm{dA}4..& \left(\mathrm{A1}\right)\end{array}$

An electrophotographic photoreceptor includes a conductive substrate; and a photosensitive layer disposed on the conductive substrate and including a charge generation layer and a charge transport layer, in which the charge transport layer has an average thickness of 30 m or greater, the charge transport layer contains a polyarylate resin, and an absorption spectrum measured by peeling off the photosensitive layer and dissolving the photosensitive layer in tetrahydrofuran satisfies Expression (1) and Expression (2),

[00001]$\begin{array}{cc}\mathrm{Iu}0.95Im& \mathrm{Expression}\left(1\right)\end{array}$$\begin{array}{cc}1.05ImI1& \mathrm{Expression}\left(2\right)\end{array}$ in a case where a total length of the electrophotographic photoreceptor in an axial direction is defined as L, Im represents an absorbance of the photosensitive layer at a wavelength of 678 nm, which is peeled from a center of the electrophotographic photoreceptor in the axial direction, Iu represents an absorbance of the photosensitive layer at a wavelength of 678 nm, which is peeled at a position of 0.40 L from the center of the electrophotographic photoreceptor in the axial direction toward one end, and Il represents an absorbance of the photosensitive layer at a wavelength of 678 nm, which is peeled at a position of 0.40 L from the center of the electrophotographic photoreceptor in the axial direction toward the other end.