An electrophotographic photoreceptor comprising at least a photosensitive layer on a conductive substrate, wherein the photosensitive layer is a laminate having a charge transport layer and a charge generation layer, the charge transport layer contains four or more types of compounds each having a maximum absorption wavelength falling within a wavelength range of from 300 nm to 600 nm in a tetrahydrofuran solution at 25? C., and maximum absorption wavelengths falling within the wavelength range of at least four types of the compounds of said four or more types of the compounds are separated from each other by 10 nm or more.

An electrophotographic photoreceptor includes a conductive substrate and a single-layer-type photosensitive layer on the conductive substrate. The single-layer-type photosensitive layer contains a binder resin, a charge generating material, an electron transporting material, and two hole transporting materials having different redox potentials. The two hole transporting materials are a hole transporting material A and a hole transporting material B that has a redox potential lower than that of the hole transporting material A. The ratio A/B of a weight of the hole transporting material A to a weight of the hole transporting material B is about 12/1 or more and about 36/1 or less.

An electrophotographic photosensitive member (1) includes a conductive substrate (2) and a photosensitive layer (3). The photosensitive layer (3) contains a charge generating material and a compound represented by general formula (1) shown below. In general formula (1), R.sup.1 and R.sup.2 each represent, independently of one another: a C1-20 alkyl group optionally having at least one of a C6-14 aryl group optionally having a substituent and a C2-20 alkoxycarbonyl group; a C6-14 aryl group optionally having a C1-20 alkyl group; a C3-10 cycloalkyl group; or a C1-6 alkoxy group. ##STR00001##

An electrophotographic photosensitive member includes a surface layer containing a charge transporting material and a polyester resin having a specific structure.

Provided is a process cartridge having a charging member and an electrophotographic photosensitive member to be charged by being in contact with the charging member, wherein the electrophotographic photosensitive member has a support and a photosensitive layer in this order, and a surface layer of the electrophotographic photosensitive member has a Martens hardness of 230 N/mm.sup.2 or less.

An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer is a single-layer photosensitive layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The binder resin contains a polyarylate resin (1). The polyarylate resin is represented by general formula (1). The photosensitive layer has a scratch resistance depth of no greater than 0.50 m. The photosensitive layer has a Vickers hardness of at least 17.0 HV. ##STR00001##

An electrophotographic photosensitive member includes a conductive substrate and a single-layer photosensitive layer. The photosensitive layer contains at least a charge generating material and a compound represented by general formula (1). In general formula (1), R.sup.1 represents an aryl group having a carbon number of at least 6 and no greater than 22 and optionally having an alkyl group having a carbon number of at least 1 and no greater than 10, an alkyl group having a carbon number of at least 3 and no greater than 20, an aralkyl group having a carbon number of at least 7 and no greater than 20, a cycloalkyl group having a carbon number of at least 3 and no greater than 20, or an alkoxy group having a carbon number of at least 1 and no greater than 6. Chemical groups R.sup.2 each represent a halogen atom.

##STR00001##

A polyarylate resin is represented by general formula (1) shown below. In general formula (1), R.sup.1 and R.sup.2 each represent, independently of one another, a hydrogen atom or a methyl group. r and s each represent an integer of at least 0 and no greater than 49. t and u each represent an integer of at least 1 and no greater than 50. r+s+t+u=100. r+t=s+u. X and Y each represent, independently of one another, a divalent group represented by chemical formula (1-1), chemical formula (1-2), chemical formula (1-3), or chemical formula (1-4). X and Y are different from one another. ##STR00001##

An electrophotographic photoreceptor includes a conductive substrate, a charge-generating layer disposed on the conductive substrate, and a charge-transporting layer as an outermost layer disposed on the charge-generating layer and containing a binder resin and a charge-transporting material, wherein the average particle size of the crystal of the charge-transporting material is approximately from 0.1 m to 5.0 m.

An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer is a single layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The photosensitive layer has a scratch resistance depth of no greater than 0.50 m.