A printing drum mounting system and method of assembling the mounting system. The mounting system comprising a rotatable shaft; a first mount and a second mount arrangeable on the shaft to clamp a printing drum therebetween, wherein the first mount comprises a first engaging surface to form a mating contact with a corresponding first end surface of the printing drum and the second mount comprises a second engaging surface to form a mating contact with a corresponding end surface of the printing drum; a double-walled flexure to flexibly mount the first engaging surface and the shaft, the flexure to provide the first engaging surface with a single degree of freedom of axial movement relative to the shaft and to maintain mating contact between the first engaging surface and the first end surface of the printing drum as the printing drum thermally expands and contracts; and a releasable fixing to align and rigidly engage the second engaging surface relative to the shaft.

Disclosed herein is an imaging member that includes a substrate, a charge generating layer, a charge transport layer; and an outermost layer comprising a structured organic film (SOF) comprising a fluorinated molecular building block and a hole molecular building block, wherein the fluorinated molecular building block is present in the SOF of the outermost layer in an amount of from about 1 weight percent to about 20 weight percent of the SOF.

A fluorine-containing resin particle contains 0 or more and 30 or less carboxyl groups per 10.sup.6 carbon atoms and 0 ppm or more and 3 ppm or less of a basic compound.

An electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer on the conductive substrate. The outermost surface layer of the electrophotographic photoreceptor contains fluorine-containing resin particles, a fluorine graft polymer, and an acidic compound having an acid dissociation constant (pKa) of 3 or less in water at 25° C. The amount of the acidic compound relative to the outermost surface layer is 100 ppm or more and 10000 ppm or less.

An electrophotographic photosensitive member includes: a conductive support; a charge generation layer disposed on the conductive support, the charge generation layer including a charge generating material and a vinyl copolymer, the vinyl copolymer including a structural unit including a chlorine atom, a structural unit including an acyloxy group, and a structural unit including an aromatic polycarboxylic acid structure, a proportion of the structural unit including a chlorine atom to all the structural units being 80% by mass or more, a proportion of the structural unit including an aromatic polycarboxylic acid structure to all the structural units being 0.5% by mass or more; and a charge transport layer disposed on the charge generation layer, the charge transport layer including a charge transporting material and a binder resin.

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.

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.

A rectifying device includes: a first flow channel member that has an annular first flow channel through which a fluid flows in an axial direction, the first flow channel being provided between an inner peripheral wall and an outer peripheral wall; a second flow channel member that has a second flow channel between the inner peripheral wall and the outer peripheral wall, the second flow channel being provided upstream of the first flow channel in a flowing direction of the fluid and being connected with the first flow channel along an entire circumference; an inflow section that is provided at the second flow channel member and that allows the fluid to flow into a circumferential area of the second flow channel located away from the first flow channel in the axial direction; a first guide wall that is provided within the second flow channel at a position located away from the inflow section in a circumferential direction and that guides the fluid flowing toward a first side in the circumferential direction through the second flow channel toward the first flow channel; and a second guide wall that is provided within the second flow channel at a position adjacent to the first guide wall in the circumferential direction, the second guide wall guiding the fluid flowing toward a second side in the circumferential direction through the second flow channel toward the first flow channel and being disposed in a direction intersecting the first guide wall.

A coating device includes: a coating liquid holding part provided with an upper opening portion and a lower opening portion and holding a coating liquid that is supplied from a coating liquid supply part; and an annular body that is disposed inside the coating liquid holding part, through which a cylindrical body penetrating the upper opening portion and the lower opening portion of the coating liquid holding part penetrates, and in which the coating liquid held by the coating liquid holding part flows in from an upper side and flows out from a lower side with a relative movement to the cylindrical body, the annular body being installed to be relatively displaceable along an installation surface intersecting a direction of the relative movement with respect to the coating liquid holding part.