The present invention relates to a single-layer type electrophotographic photoreceptor for positive charging, comprising: a conductive support; and a photosensitive layer disposed on the conductive support and comprising a binder resin, a charge generation material, a hole transport material and a specific electron transport material within the same layer, wherein the photosensitive layer contains a specific aromatic compound.

A single-layer photosensitive layer included in an electrophotographic photosensitive member contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The binder resin includes a polyarylate resin. The polyarylate resin includes repeating units represented by formulas (1), (2), (3), and (4).

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The percentage of the number of repeats of the repeating unit represented by formula (3) relative to a total of the number of repeats of the repeating unit represented by formula (1) and the number of repeats of the repeating unit represented by formula (3) is greater than 0% and less than 20%.

In a positively charging single layer type electrophotographic photoreceptor having an over coat layer, an electrophotographic photoreceptor that is excellent in mechanical strength, electric characteristics, and adhesiveness, an electrophotographic photoreceptor cartridge, and an image formation device are provided. In a positively charging electrophotographic photoreceptor having a single layer type photosensitive layer and an over coat layer, the Martens hardness on the photoreceptor surface satisfies the prescribed condition, and preferably the photosensitive layer satisfies the particular relational expression of the contents and the molecular weights of the hole transporting substance and the electron transporting substance contained therein, thereby solving the problem.

An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer of a single layer. The photosensitive layer contains a charge generating material, a binder resin, a hole transport material, and an electron transport material. The binder resin includes a polyester resin. The polyester resin includes a first repeating unit represented by general formula (1) shown below and a second repeating unit represented by general formula (2) shown below. ##STR00001##
A content percentage of the polyester resin in the photosensitive layer is at least 0.3% by mass and no greater than 7.0% by mass.

An electrophotographic photosensitive member includes a single-layer type photosensitive layer including phthalocyanine or a derivative thereof and an electron transport material. The electron transport material includes at least one first compound represented by formula (1) or (2) shown below and at least one second compound represented by formula (3), (4), or (5) shown below. A total amount of the at least one first compound and the at least one second compound is no less than 60 parts by mass and no greater than 120 parts by mass relative to 100 parts by mass of the binder resin. An amount of the at least one first compound is no less than 35 parts by mass and no greater than 80 parts by mass. An amount of the at least one second compound is no less than 25 parts by mass and no greater than 40 parts by mass. ##STR00001##

Provided are a photoconductor for electrophotography that has sufficiently high sensitivity and excellent potential stability during repeated printing in various environments, and does not cause problems, such as deterioration of gradation or generation of memory images, especially when applied to monochrome high-speed printers and small medium-speed tandem color printers, as well as a method of manufacturing the photoconductor for electrophotography, and an electrophotographic equipment. The positively-charged photoconductor for electrophotography includes a conductive substrate; and a photosensitive layer formed on the conductive substrate, in which the photosensitive layer contains electron transport materials, and at least one of the electron transport materials contains an azoquinone derivative having a structure represented by general formula (ET1) below:

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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. An area ratio A/B is 0.0045 or less, where A is an absorbance area at a wavelength of 1647 cm.sup.−1 to 1627 cm.sup.−1 and B is an absorbance area of a peak at a wavelength of 1800 cm.sup.−1 to 1647 cm.sup.−1 in an infrared absorption spectrum measurement of the protective layer. The photosensitive layer contains at least a hole transport material (HTM) and a radical acceptor compound. The electrophotographic photoreceptor is an electrophotographic photoreceptor including a protective layer with a high curing degree and having good initial electrical characteristics, excellent strong exposure characteristics, and excellent transfer repeatability.

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, an electron transport material, a binder resin, and a hole transport material.

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The electron transport material includes a compound represented by general formula (1). The binder resin includes a polycarbonate resin having an end group and a main chain represented by general formula (10).

A compound is represented by general formula (1). In general formula (1), R.sup.1 and R.sup.2 each represent, independently of one another, a hydrogen atom, a methyl group, or an ethyl group, and a sum of the number of carbon atoms of the chemical group represented by R.sup.1 and the number of carbon atoms of the chemical group represented by R.sup.2 is 2. R.sup.3 and R.sup.4 each represent, independently of one another, a hydrogen atom, a methyl group, or an ethyl group, and a sum of the number of carbon atoms of the chemical group represented by R.sup.3 and the number of carbon atoms of the chemical group represented by R.sup.1 is 2. A photosensitive layer of an electrophotographic photosensitive member contains at least a charge generating material, a hole transport material, and a binder resin. The hole transport material includes a compound represented by general formula (1) ##STR00001##

An electrophotographic photoconductor includes a conductive substrate; and a photosensitive layer provided on the conductive substrate and containing a charge generation material, a hole transport material, a first electron transport material, from 3% by mass to 40% by mass of a second electron transport material, a resin binder, and an inorganic oxide filler surface-treated with a silane coupling agent. In a dipole-dipole force component (a Hansen solubility parameter), the first electron transport material and the silane coupling agent have a difference of ΔSPa<2.50; the second electron transport material and the silane coupling agent have a difference of ΔSPb<2.50; and the first electron transport material and the second electron transport material have a difference of 0.30<ΔSPc<1.00. In a London dispersion force component (a Hansen solubility parameter), the resin binder and the silane coupling agent have a difference of ΔSPd<2.00.