A cleaning blade in which a Young's modulus of a contact portion that comes into contact with a member to be cleaned is 14 MPa or more and 25 MPa or less, and a tip angle of the contact portion is 55 degrees or more and 80 degrees or less.

A cleaning member includes: an elastic contact plate that includes a distal end surface with a corner portion to be brought into contact with a cleaning target surface, which is moved with toner attached thereto, of a cleaning target body; and a support plate bonded to the elastic contact plate from a back surface side of the elastic contact plate to support the elastic contact plate, the support plate being more rigid than the elastic contact plate. The distal end surface of the elastic contact plate projects from a distal end surface of the support plate.

An image forming apparatus includes a rotatable image bearing member, a developing member, a transfer member, and a brush contacting a surface of the image bearing member in a contact portion downstream of a transfer portion and upstream of a developing portion with respect to a rotational direction of the image bearing member. The toner which is not transferred onto a toner image receiving member is collected by the developing member. In a charging series, the toner is positioned on the same side as a normal charge polarity of the toner relative to the brush. In the contact portion, a maximum value of a contact pressure of 0.7 gf/mm.sup.2 or more and 3.5 gf/mm.sup.2 or less, a maximum contact area ratio is 18% or more and 74% or less, and a Clark-Evans index of the brush is 1 or more.

An image forming apparatus includes a main body housing and a process cartridge demountable from the main-body housing. The process cartridge includes a drum cartridge and a toner cartridge. The drum cartridge includes a photosensitive drum, a drum cleaner, an outlet with an outlet opening, an outlet shutter, and a lever. The lever is pivotable between a first position at which the lever places the outlet shutter closing the outlet opening and a second position at which the lever places the outlet shutter opening the outlet opening. When the lever is located at the first position, the process cartridge is demountable from the main-body housing. When the lever is located at the second position, the process cartridge is disabled to be demounted from the main-body housing.

A cleaning member includes plural bristles including tips that come into contact with an object to be cleaned having a surface including recesses and projections; and a brush base to which the bristles are attached. The bristles each have a non-circular cross-section including a projecting portion that projects toward an outer periphery, at least the projecting portion having a size such that the projecting portion is capable of entering the recesses in the object to be cleaned.

An image forming apparatus includes an image bearing member, an intermediate transfer member, a reinforcing member, and a collection unit having a contact member and a support member. The contact member extends in a longitudinal direction that is orthogonal to an intermediate transfer member movement direction. One end of the contact member is fixed to the support member and the other end is in contact with the intermediate transfer member as a free end. When a maximum region in the longitudinal direction where an image is formable on a transfer medium having a maximum size that is supported by the image forming apparatus is defined as an image forming region, at least part of the reinforcing member is located outside the image forming region and, on one end side of the contact member, the reinforcing member is provided on an inner side than the end of the contact member.

A paper dust collecting member removes and collects paper dust attached to a conveying roller, and is attachable along the attaching direction parallel to the axial direction of the conveying roller via an opening portion provided in a side plate of an apparatus main body. The paper dust collecting member has a removing member and a holding member. The removing member removes paper dust attached to the conveying roller. The holding member holds the removing member. The holding member includes a protrusion portion which is disposed, on its distal end portion side, along a side surface of the removing member and which protrudes in the thickness direction of the removing member beyond a contact surface of the removing member.

An image forming apparatus includes a rotatable cylindrical component to be cleaned, and a bar brush having a base substrate and bristles. The base substrate of the bar brush is located at a fixed position relative to the component to be cleaned. The bristles extend from the base substrate to contact the component to be cleaned. The bristles have free ends that form a tip end surface of the bar brush. The tip end surface has a curved shape that conforms with a surface of the component, when the bristles are not in contact with the surface to be cleaned.

A cleaning member includes a core and first and second foamed elastic layers wound around an outer peripheral surface of the core in a double-helical pattern. The compressive stress F1 of the first foamed elastic layer is greater than the compressive stress F2 of the second foamed elastic layer. The cleaning member cleans a member to be cleaned with the first and second foamed elastic layers in contact with a surface of the member to be cleaned.

A photosensitive drum is rotatably supported in a main body. A developing cartridge is detachably mountable on the main body in a state where the photosensitive drum is supported in the main body. The developing cartridge includes a developing device and a frame. The developing device includes a developing roller disposed in confrontation with the photosensitive drum to supply developer to the photosensitive drum when the developing cartridge is mounted in the main body, and a developer-accommodating portion configured to accommodate developer. The frame includes a waste-developer-accommodating portion configured to accommodate waste developer and supports the developing device that is movable relative to the frame. The frame is disposed on an opposite side of the developing roller from the photosensitive drum. An urging member is disposed between the frame and the developing device to urge the developing roller toward the photosensitive drum.