Provided is a positively charged electrophotographic photoconductor, a manufacturing method thereof, and an electrophotographic apparatus using the same. The positively charged electrophotographic photoconductor includes an electroconductive support and a single layer-type photosensitive layer provided thereon including a charge generation material, a hole transport material, an electron transport material, and a mixed binder resin. Alternately, the positively charged electrophotographic photoconductor includes an electroconductive support; a charge transport layer provided on the electroconductive support and containing at least a hole transport material, and a binder resin; and a charge generation layer provided on the charge transport layer and including at least a charge generation material, a hole transport material, an electron transport material, and a mixed binder resin. In either embodiment, the mixed binder resin contains at least two resins including a polycarbonate-based resin selected to provide the mixed binder resin with a water vapor permeability ranging from 5 to 13 g/m.sup.2.Math.day.

An electrophotographic photosensitive member with suppressed potential variation even in the case that a protective layer including a cured material of a composition having a polymerizable functional group is used is provided. An electrophotographic photosensitive member including a support, a charge generation layer, a charge transport layer containing a charge transporting material, and a protective layer, in the order presented, wherein the charge transport layer contains a polycarbonate resin having a structure selected from a group A and a structure selected from a group B, and the protective layer includes a cured material of a composition containing a compound having at least a functional group selected from chain-polymerizable functional groups and sequential polymerizable functional groups.

A polyarylate resin is represented by general formula (1) shown below. In general formula (1), R.sup.1, R.sup.2, R.sup.3, and R.sup.4 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. r and t may be the same as or different from each other. s and u may be the same as or different from each other. X represents a divalent group represented by chemical formula (2A), (2B), (2C), or (2D). Y represents a divalent group represented by chemical formula (4A), c (4B), or (4C). X and Y are different from each other.

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An electrophotographic photosensitive body includes at least a photosensitive layer and a protective layer sequentially laminated on an electroconductive support, wherein the protective layer has a domain containing perfluoropolyether.

A polyarylate resin includes at least one type of repeating unit represented by a general formula (1), at least one type of repeating unit represented by a general formula (2), and a terminal group represented by a general formula (3). R.sup.1, R.sup.2, R.sup.3, and R.sup.4 each represent, independently of one another, a hydrogen atom or a methyl group. R.sup.5 and R.sup.6 each represent, independently of each other, a hydrogen atom or a C.sub.1-4 alkyl group. R.sup.5 and R.sup.6 may bond together to represent a C.sub.5-7 cycloalkylidene group. X.sup.1 represents a divalent group represented by a chemical formula (2A), (2B), (2C), or (2D) with the proviso that when only one type of repeating unit represented by the general formula (2) is included, X.sup.1 does not represent a divalent group represented by the chemical formula (2D). R.sup.f represents a chain aliphatic group having at least one fluoro group. ##STR00001##

An electrophotographic photoreceptor includes a conductive support and a single-layer photosensitive layer. The conductive support has an outer peripheral surface with a maximum surface roughness height (Rmax) of about 4.0 m or less, and the outer peripheral surface has a recess with a depth-to-aperture size ratio (depth/aperture size) of about 0.03 or more and about 0.12 or less. The single-layer photosensitive layer is disposed on the conductive support and has a thickness of about 20 m or more and a modulus of elasticity of about 4.5 GPa or more.

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 hole transport material, an electron transport material, and a binder resin. An optical response time is at least 0.05 milliseconds and no greater than 0.85 milliseconds. The binder resin includes a polycarbonate resin including a repeating unit represented by general formula (1) shown below and a repeating unit represented by general formula (2) shown below.

##STR00001##

The present invention aims to provide an electrophotographic photoreceptor including a charge transport layer and being excellent in electrical properties and adhesiveness while exhibiting sufficient abrasion resistance indispensable for prolonging the life, and an electrophotographic photoreceptor cartridge and an image forming apparatus including the electrophotographic photoreceptor, which is an electrophotographic photoreceptor including a charge transport layer including at least two layers, wherein an elastic deformation ratio of a binder resin contained in a first charge transport layer which is an outermost layer and an elastic deformation ratio of a binder resin contained in a second charge transport layer satisfy a predetermined relationship.

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 image forming apparatus includes: a transferer that transfers a toner image formed on a surface of a photo-conductor onto an image carrier; and an irradiator that irradiates the surface of the photo-conductor before transfer with light such that a potential of an image area where the toner image has been formed and a potential of a non-image area where the toner image has not been formed in the photo-conductor before transfer satisfy formula (1):

0|Va||Vb|200 [V](1) where |Va| represents the potential of the image area after the surface of the photo-conductor before transfer is irradiated with light, and |Vb| represents the potential of the non-image area after the surface of the photo-conductor before transfer is irradiated with light.