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 photosensitive layer of an electrophotographic photosensitive member is a single layer and contains a charge generating material, a hole transport material, a first electron transport material, a second electron transport material, and a binder resin. The binder resin includes a polyarylate resin. The polyarylate resin includes repeating units (1), (2), (3), and (4).

##STR00001##

A percentage of the number of repeats of the repeating unit (3) relative to the total of the number of repeats of the repeating units (1) and the number of repeats of the repeating unit (3) is greater than 0% and less than 20%. The first electron transport material includes a compound represented by formula (A15) or (A16).

##STR00002##

The second electron transport material includes a compound represented by formula (B10), (B11), (B12), (B13), or (B14)

##STR00003##

An electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer containing a charge transport portion including a first hole transport material represented by General Formula (1) below, a cured resin, and a cross-linked structure there between: ##STR00001## where Za is a polymerizable functional group with a Structural Formula (2), (3), or (4), Zb is a divalent group with a Structural Formula (6) or (7), Ra, Rb, Rc and Rd each are one of a branched or unbranched alkyl group having from 1 to 6 carbon atoms, an alkoxy group having from 1 to 6 carbon atoms, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted styryl group, I is 0 or 1 when Za is (2) or (4) and 1 when Za is (3), m is from 0 to 5, n, o, and p are each from 0 to 4, q is from 1 to 3.

The electrophotographic apparatus includes: an electrophotographic photosensitive member; a charging unit; an image-exposing unit; a charge transfer amount-sensing unit for sensing the amount of charge transferred to the electrophotographic photosensitive member; and an exposed portion potential-controlling unit for controlling the potential of each of the exposed portions of the electrophotographic photosensitive member based on a sensing result, which is obtained by charging the electrophotographic photosensitive member with the charging unit, performing image exposure with the image-exposing unit in at least one light amount weaker than a light amount in which the normalized radius of curvature R of the electrophotographic photosensitive member represented by the following equation (E1), the normalized radius of curvature being obtained by a method of measuring an EV curve, shows a minimum, and in at least two light amounts stronger than the light amount in which the normalized radius of curvature shows the minimum.

[00001]$\begin{array}{cc}R=\frac{{\left[1+{\left(\frac{\mathrm{dy}}{\mathrm{dx}}\right)}^2\right]}^{3/2}}{.Math.\frac{d^2}{{\mathrm{dx}}^2}.Math.}& \left(E1\right)\end{array}$

An electrophotographic photosensitive member has a charge generation layer having a film thickness of 0.2 μm or larger and a charge transport layer on a support, wherein in a case where, at 23.5° C. and 50% RH, the photosensitive member is subjected to operations and measurement of: specific (1), (2), (3) and (4), an absolute value of a slope α of a linear approximation straight line is 4×10.sup.−3 or smaller, in a range where the electric field strength E is 10 to 40 V/μm, which is expressed by a relational expression between a recombination constant P.sub.e and an electric field strength E, which is obtained from a specific graph which has been obtained by repeatedly performing the specific operations and measurement of (1) to (4) while changing I.sub.exp from 0.000 to 1.000 μJ/cm.sup.2 at intervals of 0.001 μJ/cm.sup.2.

An electrophotographic photosensitive member includes: a support; an undercoat layer; a charge generation layer; and a charge transport layer, wherein the undercoat layer contains a polyamide resin and a titanium oxide fine particle, and on the surface of the undercoat layer, an arithmetic mean roughness Ra and an average length Rsm of a roughness curve element both according to JIS B0601:2001 satisfy Ra≤50 nm and 0.1≤Ra/Rsm≤0.5; and the charge generation layer contains a hydroxygallium phthalocyanine pigment, wherein the hydroxygallium phthalocyanine pigment includes crystal particles having a crystal form exhibiting peaks at 7.4°±0.3° and 28.2°±0.3° at Bragg angles 2θ in a spectrum of X-ray diffraction using a CuKα, ray; and in a size distribution of the crystal particles, which is measured using small-angle X-ray scattering, a peak exists in a range of 20 to 50 nm, and the peak has a half-value width of 50 nm or smaller.

Provided is an electrophotographic apparatus which uses a light emitting diode array as an exposure unit and exposes a photosensitive member to a quantity of light from the LED array whose average light quantity satisfies 0.8×Emin or more and 1.1×Emin or less on condition that a normalized radius of curvature R of a normalized graph derived from the E-V curve of the photosensitive member has a minimum value of 0.24 or less, and a light quantity at the minimum value of the normalized radius of curvature R is Emin [μJ/cm.sup.2]. This electrophotographic apparatus prevents both the occurrence of image unevenness due to light quantity variation among the elements of the LED array and the generation of ghost images due to a rest potential.

Provided are an electrophotographic photoconductor being resistant to abrasion even in long-term use, having highly sensitive electric characteristics, being capable of maintaining a high retention rate, and being capable of providing a stable image without filming, a method of manufacturing the same, and an electrophotographic device. The photoconductor includes an electroconductive substrate (1), a charge generation layer (3), and a charge transport layer (4); the charge transport layer contains a hole transport material, a resin binder, an electron transport material, and an inorganic oxide; the charge generation layer contains a charge generation material; the masses of the hole transport material, the resin binder, the electron transport material, and the inorganic oxide in the charge transport layer respectively denoted by a to d satisfy 1.5≤b/a≤5.7, 0.005≤c/a≤0.35, 0.05≤d/a≤0.70, a≥c+d, and c/d≥0.01; the hole transport material contains a compound expressed by formula (A-1); and the charge generation material contains titanyl phthalocyanine having an exothermic peak at 251±5° C., a half-value width of the exothermic peak equal to or less than 15° C., and a heating value equal to or greater than 1.0 mJ/mg when a temperature rise condition is 20° C./min in differential scanning calorimetry, and having an X-ray diffraction peak at 27.2±0.3°. ##STR00001##

Provided is a photoelectric conversion device including: a support; a charge-transporting layer including an organic charge-transporting material or a sensitizing dye electrode layer including an organic sensitizing dye, where the charge-transporting layer or the sensitizing dye electrode layer is disposed on the support; and a ceramic film disposed on the charge-transporting layer or the sensitizing dye electrode layer.

Provided is an electrophotographic photosensitive member including a support, an undercoat layer, a charge-generating layer, and a charge-transporting layer in the stated order, wherein with regard to an S.sub.0, an S.sub.1, an S.sub.2, an S.sub.3, and an S.sub.4 determined by a specific procedure (A), a ratio S.sub.1/S.sub.0 is 0.34 or less, and one of the S.sub.2, the S.sub.3, or the S.sub.4 is a positive value, and the other two thereof are negative values, or two thereof are positive values, and the other one thereof is a negative value.