An electrostatic image developing carrier includes core particles provided by dispersing a magnetic powder in a resin and resin cover layers covering the core particles, wherein the resin cover layers have a surface coverage of 96 area % or more, the resin cover layers include 10 mass % or more and 50 mass % or less of inorganic particles relative to a total mass of the resin cover layers, and the inorganic particles in surfaces of the carrier have a surface exposure ratio of 6 atomic % or more and 15 atomic % or less determined by X-ray photoelectron spectroscopy.

An electrostatic image developer includes a toner including toner particles and an external additive, wherein an amount of the external additive that is loose relative to a total mass of the external additive is 5 mass % or less, and a carrier including magnetic particles and resin cover layers covering the magnetic particles and including inorganic particles, wherein a fine-irregularity-structure surface roughness of surfaces three-dimensionally analyzed has, in an analysis region, a ratio B/A of an irregularity-surface area B to a plan-view area A of 1.020 or more and 1.100 or less.

A toner for developing an electrostatic charge image contains toner particles containing at least one binder resin, a release agent, and a coloring agent, and a cross-sectional image of the toner particles meets requirements (1) and (2): requirement (1), an average of ten or more domains, per toner particle, of the release agent have an area of 0.5% or more and 5.0% or less of the area of the toner particle; requirement (2), in a Voronoi tessellation generated from the centroids of the domains of the coloring agent, the mean area of the Voronoi cells is 0.020 μm.sup.2 or more and 0.060 μm.sup.2 or less, and the standard deviation of the areas of the Voronoi cells is 0.010 μm.sup.2 or less.

A developing apparatus includes a developer carrying member configured to carry developer, and a developer supply member configured to supply the developer to the developer carrying member, the developer supply member including a shaft, first and second driving members disposed at a first end and a second end of the shaft, respectively, and a toner supply unit disposed between the first end and the second end of the shaft, wherein the first driving member receives a driving force for rotating the developer supply member, and the second driving member outputs the driving force, and wherein the second driving member is mounted to the shaft without play in a rotational direction of the developer supply member with respect to the shaft.

As a new negatively charging electrophotographic photoconductor having a cured resin based protective layer that does not necessitate a heat treatment for enhancing the electric characteristics, a negatively charging electrophotographic photoconductor having a structure including a photosensitive layer and a protective layer containing a cured product formed by curing a curable compound on a conductive support in this order, the photosensitive layer containing at least a hole transporting material (HTM) and a radical acceptor compound or an electron transporting material (ETM), the hole transporting material (HTM) being a compound having an energy difference between a HOMO level and a LUMO level of 3.60 eV or less, and having a HOMO level of −4.50 eV or less based on the vacuum level is proposed.

In an image forming apparatus, a tray unit to which a cartridge is detachably mounted, and that is configured to be capable of moving between an internal position situated within the apparatus main body and an external position situated outside, includes first and second side plates configured to support the cartridge, and they are each made of metal, and include a supporting portion and an outer side portion, the supporting portions includes positioning portions configured to come into contact with the cartridge to position the cartridge as to an image forming position. The apparatus main body includes first and second pressing members each capable of moving between pressing positions at which the cartridge is pressed, and separated positions separated from the cartridge. The first and second pressing members are disposed each intersecting with imaginary planes that is orthogonal to the longitudinal direction and intersect the positioning portions.

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

Provided is an electrophotographic photosensitive member that includes a support, a charge generation layer on the support, and a charge transfer layer on the charge generation layer and that satisfies specifications on an EV curve based on a measurement method of NESA-EV curve. The electrophotographic photosensitive member can exhibit high character quality and a digital gradation characteristic in a low-line-number halftone while maintaining an analog gradation characteristic in a high-speed process.

The image forming apparatus includes a drum cartridge having a photosensitive drum and a drum drive input member; a developing cartridge configured to be movably mounted to the drum cartridge, the developing cartridge comprising a developing roller disposed so as to face the photosensitive drum and a developing drive input member; a drum drive transmission member configured to engage with the drum drive input member and configured to transmit drum driving force to the drum drive input member while permitting a positional gap of the drum drive input member within a predetermined range; and a developing drive transmission member configured to engage with the developing drive input member and configured to transmit developing driving force to the developing drive input member while permitting a positional gap of the developing drive input member within a predetermined range.

Provided is an electrophotographic electro-conductive member including a support having an electro-conductive outer surface, and an electro-conductive layer. The electro-conductive layer has a matrix containing a crosslinked product of a first rubber and domains containing a crosslinked product of a second rubber and an electron conductive agent. When measuring an impedance by applying alternating voltage between the outer surface of the support and a platinum electrode on an outer surface of the electro-conductive layer while changing a frequency, a slope at specific frequencies is −0.8 to −0.3 in a double logarithmic plot, and an impedance at specific frequency range is 1.0×10.sup.4Ω to 1.0×10.sup.11Ω. When measuring an impedance by applying alternating voltage between the outer surface of the support and a platinum electrode on an outer surface of the electrophotographic electro-conductive member while changing a frequency, an impedance at specific frequency range is 1.0×10.sup.5Ω to 1.0×10.sup.11Ω.