An electrophotographic apparatus having an electrophotographic photosensitive member, a charging unit, and a developing unit for forming a toner image on a surface of the electrophotographic photosensitive member, wherein the charging unit has a conductive member disposed to be contactable with the electrophotographic photosensitive member; a conductive layer at the surface of the conductive member has a matrix and a plurality of domains dispersed in the matrix; at least a portion of the domains is exposed at the outer surface of the conductive member; the outer surface of the conductive member is constituted of at least the matrix and the domains; a volume resistivity R1 of the matrix is greater than 1.00×10.sup.12 Ω.Math.cm; a volume resistivity R2 of the domains is smaller than R1; the developing unit contains the toner; and a dielectric loss tangent of the toner is at least 0.0027.

A drum cartridge includes: a photosensitive drum rotatable about a drum axis extending in an axis direction; a drum cleaner including a cleaning member cleaning a circumferential surface of the photosensitive drum, and a cleaning housing accommodating transfer residual toner removed from the circumferential surface of the photosensitive drum by the cleaning member; a first drum side plate supporting a first end portion of the photosensitive drum; a second drum side plate located distant from the first drum side plate in the axis direction and supporting a second end portion of the photosensitive drum; a pipe located between the first drum side plate and the second drum side plate in the axis direction and extending in the axis direction; and a conveyor device conveying the transfer residual toner from the cleaning housing to the pipe.

An image forming apparatus includes a detection sensor to irradiate light to a recording medium passing through a printing path, and detect an amount of light, a driving device to move a cleaning member to a cleaning region overlapping the printing path to clean a light window of the detection sensor, and a processor to confirm a position of the cleaning member based on the amount of light detected by the detection sensor and control the driving device to move the cleaning member based on the confirmed position.

There is provided an electrophotographic photosensitive member comprising: a support, a photosensitive layer, and a surface layer in this order, wherein an outer surface of the electrophotographic photosensitive member exhibits a wrinkled shape by having a concavo-convex shape, the surface layer comprises a binder resin and an inorganic particle, and at least a part of the inorganic particle exposes at a concave portion of the concavo-convex shape.

A cartridge for an image forming apparatus includes: a process unit to be used to form an image; a first member including a first resin material; a second member including a second resin material having higher flame retardant capability than the first resin material; and an electrode member including a contact section configured to be supplied with power from an apparatus main body of the image forming apparatus. The electrode member is configured to electrically connect the apparatus main body to the process unit. The second resin material of the second member has a greater density than the first resin material of the first member. The contact section is located in the vicinity of the first and second members and is closer to the second member than to the first member.

Provided is a process cartridge that is excellent in initial charge rising performance, and in charge uniformity of a halftone image throughout a long period of time from the start of use until after endurance. Specifically, provided is a process cartridge including: an electrophotographic photosensitive member; a toner; and a developing unit, wherein the toner contains toner particles and an external additive A, the external additive A, and wherein the electrophotographic photosensitive member includes an electroconductive support, a photosensitive layer, and a surface protective layer, wherein the surface protective layer contains electroconductive particles.

A cartridge includes: a photosensitive drum; a drum cleaner for cleaning the photosensitive drum; a toner pipe for conveying collected toner; a toner container storing therein toner; and a developing device for supplying toner in the toner container to the photosensitive drum. The cartridge is detachably attachable to an image forming apparatus. The collected toner is toner removed from the photosensitive drum by the drum cleaner. The developing device includes a developing housing for storing therein toner supplied from the toner container and the collected toner conveyed by the toner pipe. The toner container has: a toner discharge port for discharging toner stored in the toner container; and a returned toner receiving port for receiving toner returned from the developing device. The developing housing has: a toner receiving port for receiving toner discharged from the toner discharge port; and a toner return port for returning toner to the toner container.

A charging member includes a conductive base material; an elastic layer that is provided on the conductive base material and has a storage elastic modulus G of 5.0 MPa or less at 100 Hz; and a surface layer that is provided on the elastic layer, in which in a Cole-Cole plot obtained by measuring the charging member in a range of 1 MHz to 0.1 Hz by an alternating current impedance method, a resistance component Ra of a capacitive semicircle including 2.5 kHz is 6.3×104Ω or less.

In a cartridge structure employing an inclinable coupling member engaging with a rotational force transmitting portion of an electrophotographic image forming apparatus, the coupling member is unable to engage with the rotational force transmitting portion of the electrophotographic image forming apparatus when the mounting and dismounting direction and the developing/spacing direction relative to the electrophotographic image forming apparatus of different from each other. Under the circumstances, a coupling lever contacting and retracting relative to the coupling member in interrelation with the mounting and dismounting operation of a developing cartridge B1, and a coupling spring for the coupling lever to apply an urging force to the coupling member are provided.

An image forming apparatus is provided, including a housing; a drum cartridge; a developing cartridge; a drawer movable between an inner position and an outer position; and a lock member provided on the drawer and movable between a lock position at which the lock member locks the drum cartridge to the drawer, and a release position at which a lock between the drum cartridge and the drawer is released. The lock member includes an operation portion for moving the lock member between the lock position and the release position. The developing cartridge includes a cover member that covers at least a portion of the operation portion in a state in which the drum cartridge is mounted to the drawer, and the developing cartridge is mounted to the drum cartridge.