An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer is a single layer and contains a charge generating material, a hole transport material, an electron transport material, and a polyarylate resin. The polyarylate resin includes repeating units represented by formulas (1), (2), and (3).

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A ratio n.sub.1/n.sub.2 of the number n.sub.1 of repeats of the repeating unit represented by formula (1) to the number n.sub.2 of repeats of the repeating unit represented by formula (2) is at least 1.0.

An object of the present invention is to provide an electrophotographic photoreceptor which can prevent an increase in potential even using a fluorine resin in a charge transport layer, and can achieve both electrical properties and abrasion resistance, and present invention relates to a lamination type electrophotographic photoreceptor, in which a charge transport layer of the lamination type electrophotographic photoreceptor contains a compound having an E_homo of −4.550 eV or more based on structure optimization calculation by density functional calculation B3LYP/6-31G (d, p) and fluorine resin particles, and a content of the fluorine resin particles is 3% by weight to 20% by weight based on a total mass of the charge transport layer.

The present invention relates to an electrophotographic photoreceptor including a conductive support and a photosensitive layer on the conductive support, and the photosensitive layer contains a polymer A containing a repeating structural unit represented by a specific formula, and a polymer B containing a repeating structural unit represented by a specific formula. In addition, the present invention relates to an electrophotographic photoreceptor cartridge and an image forming apparatus including the electrophotographic photoreceptor.

A photoconductive drum includes an elongated support element with a shaped charge generation layer. The layer extends from the support element at a single thickness along about two-thirds of a length thereof. Thicker charge generation portions provides denser optical densities compared to thinner portions allowing tailoring the photoconductive drum to compensate for imperfect optical scanning systems. A charge transport layer overcoats the charge generation layer. Optionally, an oxidation layer underlies the charge generation layer as does a protective overcoat overlying the charge transport layer.

An electrophotographic photosensitive member including a support, an intermediate layer, and a photosensitive layer in this order, wherein the intermediate layer comprises a tungsten oxide particle, and the tungsten oxide particle contains a tungsten atom, an oxygen atom, and a cesium atom.

The present invention provides an electrophotographic photoreceptor including at least a laminated photoreceptive layer in which a charge generating layer containing a charge generating substance and a charge transporting layer containing a charge transporting substance are laminated in this order on a substrate, where the charge generating substance is a titanyl phthalocyanine showing diffraction peaks at least at Bragg angles (2θ±0.2°) 7.3°, 9.4°, 11.6°, 24.2° and 27.3° in an X-ray diffraction spectrum using CuKα ray, and the laminated photoreceptive layer includes an optical absorption spectrum that has a maximum absorption at 800 to 850 nm and where a ratio Abs.sub.860 nm/Abs.sub.780 nm of a peak intensity at 860 nm (Abs.sub.860 nm) to a peak intensity at 780 nm (Abs.sub.780 nm) is 0.6 or more to 1.2 or less when a minimum absorbance at 400 to 800 nm is calibrated to 0.

There is provided an electrophotographic photoreceptor including: a conductive support; and a photosensitive layer and a protective layer containing a cured product obtained by curing a curable compound, which are sequentially disposed on the conductive support. The photoreceptor has a Martens hardness of 255 N/mm.sup.2 or more. The photosensitive layer contains at least a hole transport material (HTM), and an energy difference between a HOMO level and a LUMO level of the hole transport material (HTM) is greater than 3.6 eV and 4.0 eV or less.

There is provided an electrophotographic photoreceptor including: a conductive support; and a photosensitive layer and a protective layer containing a cured product obtained by curing a curable compound, which are sequentially disposed on the conductive support. The photoreceptor has a Martens hardness of 255 N/mm.sup.2 or more. The photosensitive layer contains at least a hole transport material (HTM), and an energy difference between a HOMO level and a LUMO level of the hole transport material (HTM) is greater than 3.6 eV and 4.0 eV or less.

An electrophotographic photosensitive member, including a cylindrical support, a charge generating layer formed on the cylindrical support, and a charge transport layer formed on the charge generating layer, in which in the charge generating layer, when a region from a central position of an image forming region to an end position of the image forming region in an axis direction of the cylindrical support is divided equally into five regions, film thicknesses of the charge generating layers in each of the regions satisfy a specific relationship with each other, and in the charge transport layer, when a region from the central position of the image forming region to the end position of the image forming region in the axis direction of the cylindrical support is divided equally into five regions, film thicknesses of the charge transport layers in each of the regions satisfy a specific relationship with each other.

Provided an electrophotographic electro-conductive member that can stably suppress an occurrence of fogging in an electrophotographic image. The member comprises a support having an electro-conductive outer surface, and an electro-conductive layer on the outer surface of the support, the electro-conductive layer having a matrix including a cross-linked product of a first rubber, and domains dispersed in the matrix, the domains each includes a cross-linked product of a second rubber and an electro-conductive particle, at least some of the domains is exposed to the outer surface of the electro-conductive member to constitute protrusions on an outer surface of the member, the outer surface of the electro-conductive member is constituted by the matrix and the domains exposed to the outer surface of the electrophotographic electro-conductive member, the electrophotographic electro-conductive member has an impedance of 1.0×10.sup.3Ω or more and 1.0×10.sup.8Ω or less, and some of the domains satisfy two specific requirements.