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.

A charging member may include a surface layer. The surface layer may include a urethane resin, an electron conducting agent, an azo-based metal complex compound, and a quaternary ammonium salt.

An image forming apparatus includes an image carrier, a charging device, a developing device, a transfer device, a development power supply, a current measurement device, and a processor. The development power supply applies a predetermined bias voltage to the developing device. The processor functions as a calculator and a controller. The calculator calculates a surface potential of the image carrier based on the development current measured by the current measurement device. The controller controls the charging device, the developing device, the transfer device, and the development power supply. The controller sets a tentative transfer current to be flowed through the transfer device while the calculator calculates the surface potential.

An image forming apparatus includes a photosensitive member, a charging member, a charging power source, a developing member, a transfer member, a transfer power source, an acquiring portion, and a controller. The controller controls a charging voltage to be a first charging voltage when an electric resistance value of the transfer member is a first resistance value and to be a second charging voltage not less than the first charging voltage in absolute value when the electric resistance value is a second resistance value lower than the first resistance value, and so that a charge amount of the charging voltage when the electric resistance value is changed from the second resistance value to a third resistance value lower than the second resistance value is larger than a change amount of the charging voltage when the electric resistance value is changed from the first resistance value to the second resistance value.

An image forming apparatus includes a rotatable photosensitive member, a charging member, an exposing unit to form an electrostatic latent image by exposing the surface of the photosensitive member charged by the charging member to light, a developing member to develop the electrostatic latent image with toner. A controller controls so that a predetermined charging voltage is charged and the light is emitted by a small light quantity to a first non-print area which is a non-print area provided with the print area and the non-print area with respect to a main scanning direction, and controls so that a charging voltage smaller than the predetermined voltage is charged and exposure is not performed to a second non-print area which is provided with only the non-print area with respect to the main scanning direction.

An image forming apparatus includes a photosensitive member, a charging member, an exposure unit, a developing unit including a developing member, a motor, a contact and separation unit, a controller, an acquiring portion for acquiring information on a switching time which is a time required for switching a state of the developing member from a separated state to a contact state by executing a contact operation by the contact and separation unit, and a setting portion for setting, on the basis of the information on the switching time acquired by the acquiring portion, a start timing which is a timing when the contact operation by the contact and separation unit is started in a preparation operation and which is a timing before a region on the photosensitive member exposed to light in a light emission period reaches a developing position.

An image forming operation forms an image on a transfer target in a state in which a developing member is located at a first position where a developer is supplied to an image bearing member and a first charging voltage is applied to a charging unit. The image forming operation is followed by: a first rotating operation of rotating the image bearing member in a state in which the developing member is located at the first position and a second charging voltage smaller in absolute value than the first charging voltage is applied; and a second rotating operation of rotating the image bearing member in a state in which the developing member is located at a second position where the developer is not supplied to the image bearing member and a third charging voltage smaller in absolute value than the second charging voltage is applied.

An image forming method includes forming, fixing, and applying. The forming forms a toner image on a recording medium by an image forming device. The fixing fixes the toner image on the recording medium with heat by a fixing device. The applying applies an electric charge by a charge applying device to the recording medium on which the toner image has been fixed by the fixing device, in a state in which an output-adjustable power source for the charge applying device has an electric current that is controlled to be constant.

An image forming apparatus of the present invention includes: a body; a developing cartridge having a memory medium and a developer bearing member; a tray including a frame which is movable between a housed position and a drawn-out position and has side portions extending in the moving direction and to which the developing cartridge is attachable, an image bearing member that faces the developer bearing member when the developing cartridge is attached, a tray-side metal terminal provided on the side portion and electrically connected to the memory medium when the cartridge is attached, and a tray guide portion extending along the moving direction; a body-side metal terminal that faces the tray-side metal terminal when the tray is housed, wherein the tray-side metal terminal is provided below the tray guide portion.

An image forming apparatus includes a charging unit that charges an image bearing member, a developing unit that forms a toner image on an latent image formed on the image bearing member, a transfer unit that transfers the toner image onto a transfer material, a charge neutralizer that neutralizes a charge of the image bearing member downstream of a transfer portion and upstream of a charging portion in a rotating direction of the image bearing member, a conductive collecting unit that collects a material adhering on the image bearing member downstream of the transfer portion and upstream of the charging portion, wherein the developing unit collects residual toner on the image bearing member, an voltage application unit sets a potential difference between the voltage applied to the collecting unit and the surface electric potential of the image bearing member not more than a discharge threshold.