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.

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Compounds exhibiting high hole mobility and/or high glass transition temperatures together with favourable HOMO, LUMO and triplet levels are provided which are 2-(4-Diphenylamino)phenyl-8-(1-thianthrenyl)- dibenzothiophene and 4-(1-Thianthrenyl)-bis(triphenylamine). The compounds may be used for hole transport layers e.g. in OLED devices.

An electrophotographic photosensitive member (1) includes a conductive substrate (2) and a photosensitive layer (3). The photosensitive layer (3) is a single-layer photosensitive layer containing at least a charge generating material, an electron transport material, a hole transport material, and a binder resin. The electron transport material includes a naphthoquinone derivative represented by general formula (1). An amount of triboelectric charge of calcium carbonate as measured by charging the calcium carbonate through friction with the photosensitive layer (3) is at least +7 C/g. In general formula (1), R.sup.11 and R.sup.12 are respectively the same as R.sup.11 and R.sup.12 described in the description.

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An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer having a single-layer structure. The photosensitive layer contains a charge generating material, an electron transport material, a polycarbonate resin, and a hole transport material. The electron transport material includes a compound having a halogen atom and represented by general formula (1), (2), (3), (4), or (5). The hole transport material includes a compound represented by general formula (20), (21), (22), (23), (24), (25), (26), or (27). A charge of calcium carbonate as measured by charging the calcium carbonate through friction with the photosensitive layer is at least +6.5 C/g. A Vickers hardness of the photosensitive layer at 45 C. is at least 17.0 HV.

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An electrophotographic photoreceptor includes a conductive substrate; and a photosensitive layer arranged on the conductive substrate and containing, as a charge generating material, any one material selected from the group consisting of titanyl phthalocyanines, metal-free phthalocyanines, chlorogallium phthalocyanines and hydroxygallium phthalocyanines; and, as an electron transporting material, a naphthalene tetracarboxylic acid diimide compound represented by Formula (1) below, where R.sup.1 and R.sup.2 each represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkylene group, an alkoxy group, an alkyl ester group, a phenyl group optionally having a substituent, a naphthyl group optionally having a substituent, or a halogen element; and R.sup.1 and R.sup.2 are optionally the same or different:

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The photoreceptor realizes a stable print density even in a low-temperature environment by suppressing a reduction in print density that is caused by potential fluctuation of the photoreceptor in the low-temperature environment.

An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer containing a charge generating material, a hole transport material, a quinone derivative, and a binder resin. The quinone derivative is represented by general formula (1) or (2), where R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 each represent, independently of one another, a hydrogen atom, an alkyl group having a carbon number of at least 1 and no greater than 12, an aryl group that has a carbon number of at least 6 and no greater than 14 and that may have an alkyl group having a carbon number of at least 1 and no greater than 6, an aralkyl group having a carbon number of at least 7 and no greater than 12, or a cycloalkyl group having a carbon number of at least 3 and no greater than 10. Z represents an oxygen atom or a sulfur atom. ##STR00001##

An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer containing a charge generating material, a hole transport material, a quinone derivative, and a binder resin. The quinone derivative is represented by general formula (1) or (2), where R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 each represent, independently of one another, a hydrogen atom, an alkyl group having a carbon number of at least 1 and no greater than 12, an aryl group that has a carbon number of at least 6 and no greater than 14 and that may have an alkyl group having a carbon number of at least 1 and no greater than 6, an aralkyl group having a carbon number of at least 7 and no greater than 12, or a cycloalkyl group having a carbon number of at least 3 and no greater than 10. Z represents an oxygen atom or a sulfur atom.

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An electrophotographic photosensitive member can provide images in which black spots and fogging are suppressed and density unevenness due to coating unevenness of the charge generation layer is suppressed. The charge generation layer of the electrophotographic photosensitive member contains a gallium phthalocyanine crystal, a nitrogen-containing heterocyclic compound, and an amide compound represented by a formula (1), and a nitrogen atom in a heterocyclic ring of the nitrogen-containing heterocyclic compound has a substituent. ##STR00001##