The present invention relates to an electrophotographic photoreceptor which is a positive charging type electrophotographic photoreceptor comprising a conductive support and a photosensitive layer on the conductive support, wherein the photosensitive layer contains at least a charge generating material, a hole transport material, an electron transport material, and a binder resin in the same layer, and a residual potential VL.sub.1 at a point at which an exposure amount for forming a latent image is 0.3 μJ/cm.sup.2 is equal to or lower than 130 V when an initial surface potential V0 is set to +700 V, exposure with monochromatic light of 780 nm is performed and measurement is performed by a dynamic method.

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.

A photoconductor includes an electroconductive substrate; an intermediate layer overlying the electroconductive substrate; and a photosensitive layer overlying the intermediate layer. The intermediate layer includes a metal oxide particle and a binder resin, and satisfies the following relations (1) and (2):
Smr=Scut/Sk  (1)
0.4≦Smr≦0.6  (2)
where Smr represents an areal ratio of concave parts; Sk represents a reference area; and a Scut represents a cross-sectional area obtained by cutting a three-dimensional curved surface obtained from the reference area with an average height surface, the average height surface being a surface constituted of averaged height of all measured height data.

An electrophotographic photoreceptor includes a conductive substrate, an organic photosensitive layer on the conductive substrate, and an inorganic protective layer on the organic photosensitive layer. A layer that constitutes a surface of the organic photosensitive layer contains a charge transport material, a binder resin, silica particles, and a silicone compound.

An electrophotographic photoconductor includes a conductive substrate, and a photoconductive layer, in which an outermost surface layer contains a binder resin, a charge transporting material, fluorine-containing resin particles, and an acidic compound, the number of carboxyl groups in the fluorine-containing resin particles is 0 or more and 30 or less per 10.sup.6 carbon atoms of the fluorine-containing resin particles, and in a case where charging and exposure of the electrophotographic photoconductor are repeated 10,000 times under conditions of a charging potential of −700 V and an exposure intensity of 5 mJ/m.sup.2, an absolute value |RP.sub.1−RP.sub.10000| of a difference between a residual potential RP.sub.1 after charging and exposure once and a residual potential RP.sub.10000 after charging and exposure 10,000 times is 25 V or less.

An electrophotographic photoreceptor includes: a conductive holder; and at least a charge producing layer and a charge transport layer disposed on the conductive holder in order. The charge transport layer contains at least a binder resin, a charge transport agent and a p-type metal oxide particle.

A polyarylate resin includes repeating units (1), (2), and (4).

##STR00001##

The polyarylate resin further includes a repeating unit (3) and a percentage of the number of repeats of the repeating unit (3) relative to the total number of repeats of each of the repeating units (1) and (3) is greater than 0% and less than 50%. Alternatively, the polyarylate resin does not include the repeating unit (3).

An electrophotographic photosensitive member includes a conductive support and a photosensitive layer disposed on the conductive support. A top surface layer of the electrophotographic photosensitive member includes fluorine-containing resin particles, a fluorine-containing dispersant, and two or more charge transporting materials. When the charge transporting materials are listed in order of decreasing HOMO energy levels, a difference in HOMO energy level between each adjacent two of the charge The ratio A of the amount of each of the charge transporting materials to the total amount of the charge transporting materials satisfies the condition 1 below,

[(100/N)−(100/N×0.3)]≤A≤[(100/N)+(100/N×0.3)]  Condition 1 where N represents the number of types of the charge transporting materials included in the top surface layer.

An electrophotographic photoconductor includes: a conductive substrate; and a single-layer-type photoconductive layer that is provided on the conductive substrate, contains a binder resin, a charge generating material, a hole transporting material, and an electron transporting material, and has an index A represented by the following equation (1) in a range of −7.98 or more and −7.28 or less, Equation (1): A=(0.057×M)−(0.002×F)−(0.252×μ), in which, in the equation (1), M represents a Martens hardness of the single-layer-type photoconductive layer, F represents a Young's modulus of the single-layer-type photoconductive layer, and μ represents an elastic deformation ratio of the single-layer-type photoconductive layer.

An electrophotographic photoreceptor includes at least a photosensitive layer and a protective layer sequentially layered on a conductive support, wherein the protective layer contains a cured product of a curable composition containing p-type semiconductor fine particles, an n-type organic semiconductor, and a polymerizable compound.