A method of operating an electrophotographic printer (100) to control the optical density of a printed image is described. The method comprises providing a printing substance on a transfer member (104); emitting a pulse of heat to heat the printing substance on the transfer member to increase flowability of the printing substance on the transfer member; and transferring, from the transfer member to a substrate (108), the printing substance heated by the pulse of heat so as to provide the printed image on the substrate.

An image formation apparatus includes an image carrier, a first charging member which abuts on the image carrier and charges the image carrier, a second charging member which abuts on the image carrier and charges the image carrier, the second charging member having such resistance characteristics as being less in variation with environmental variation than the first charging member, a power supply apparatus which can apply a voltage to each of the first and second charging members, and a control device which sets a voltage to be applied to the first charging member by the power supply apparatus based on a first amount of current which flows from the power supply apparatus through the first charging member to the image carrier and a second amount of current which flows to the image carrier through the second charging member.

An electrically conductive support for use in an electrophotographic photoreceptor includes a cylindrical main body having a first end and a second end opposite to the first end in an axial direction of the main body. The main body contains an aluminum alloy and has an internal stress in a range of 30 MPa to 5 MPa. A method of producing the electrically conductive support includes preparing a substrate containing an aluminum alloy obtained at least through an extrusion step, and heat treating the substrate to obtain the electrically conductive support. The heat treating is carried out such that, when a temperature of the heat treating is defined as T ( C.) and a time of the heat treating is defined as H (hours), an amount of the heat treating Q defined by Q=TH is 800 or less.

A conductive roller includes: a core member including an outer surface along and about an axial line thereof; and a surface layer arranged along the outer surface of the core member. The surface layer includes a conductive portion formed of a conductive resin composition, and a surface roughness imparting material in a form of particles dispersed in the conductive portion. An average particle size of the surface roughness imparting material is in a range of 6 micrometers or greater and 10 micrometers or less. The number of particles of the surface roughness imparting material per unit area of the surface layer is in a range of 1.0?10.sup.4 particles per mm.sup.2 or greater and 2.0?10.sup.6 particles per mm.sup.2 or less. An average thickness of the surface layer is in a range of 3.0 micrometers or greater and 15.0 micrometers or less.

A conductive roller includes: a core member including an outer surface along and about an axial line thereof; and a surface layer arranged along the outer surface of the core member. The surface layer includes a conductive portion, and a surface roughness imparting material in a form of particles dispersed in the conductive portion. An average particle size of the surface roughness imparting material is in a range of 6 micrometers or greater and less than 10 micrometers. The number of particles of the surface roughness imparting material per unit area of the surface layer is in a range of 3.5?10.sup.5 particles per mm.sup.2 or greater and 7.5?10.sup.5 particles per mm.sup.2 or less. An average thickness of the surface layer is in a range of 0.2 micrometers or greater and 5.5 micrometers or less.

An image forming apparatus includes a photosensitive drum, a charging member, a developing member, a transfer member, a brush, a drive unit, a control unit, and a memory. The charging member charges a surface of the photosensitive drum at a charging portion. The transfer member comes into contact with the photosensitive drum to form a transfer portion. The drive unit rotatably drive the photosensitive drum. The control unit controls the drive unit to perform an image forming operation. The memory stores information about the image forming operation. In a case where the image forming operation is performed and a non-image forming operation is performed after the image forming operation, the control unit performs control such that a switching operation for stopping the photosensitive drum after the photosensitive drum is driven and re-driving the photosensitive drum is performed a plurality of times based on the information about the image forming operation.

A process cartridge includes: a drum cartridge; and a developing cartridge. The drum cartridge includes: a drum frame; a photosensitive drum rotatable about a first axis extending in a first direction; and a first memory having a first electrical contact surface. The developing cartridge is attachable to the drum frame and includes: a casing; a developing roller rotatable about a second axis extending in the first direction; a second memory having a second electrical contact surface; and a developing holder holding the second electrical contact surface such that the second electrical contact surface is movable relative to the casing. The drum cartridge further includes an elastic member that can expand and contract in a second direction crossing the first direction. The developing holder is connected to the elastic member and is movable in the second direction in a state where the developing cartridge is attached to the drum frame.

A charging roller is configured to charge a surface of an image bearing member configured to bear an image. The charging roller includes: a shaft portion; an elastic layer formed around the shaft portion; and a surface layer formed around the elastic layer, wherein particles having particle diameters within a range of 2 m or larger and 15 m or smaller and dispersed in the surface layer, and wherein a reduced peak height Spk (m), a reduced dale height Svk (m), and a core height Sk (m) with respected to the surface layer of the charging roller satisfy 4Spk+Sk8 and 0.5Svk1.

In some examples, a printing liquid developer includes a developer roller that has a hollow tubular base body formed of a material including conductive carbon fiber, a conductive, compliant layer around an outer surface of the hollow tubular base body, and an electrically conductive support separate from the hollow tubular base body and electrically contacted to a surface of the hollow tubular base body.

An image forming apparatus includes an image bearing member, a developing device, a cleaning member, a collecting container having a discharge port for collecting a developer, and a control portion that can execute a supply mode in which a region of the image bearing member that is supplied with the developer from the developing device passes through the contact region with rotation of the image bearing member to allow the cleaning member to supply the developer into the collecting container. The discharge port is provided between a first end portion and a second end portion of the image bearing member in a direction of a rotation axis line of the image bearing member. The control portion performs control such that a portion of the region supplied with the developer in the supply mode overlaps, in the direction of the rotation axis line, a position where the discharge port is provided.