A developing device includes a developing roller, a developing case, and a support. The developing roller includes a sleeve and a magnetic field generator. The sleeve is rotatable and includes a hollow shaft at an axial end of the sleeve. The magnetic field generator is irrotationally disposed inside the sleeve and includes a non-rotating shaft at an axial end of the magnetic field generator. The non-rotating shaft penetrates through the hollow shaft and projects outward. The developing case is configured to store developer and rotatably supports the hollow shaft. The support includes a fitting portion into which the non-rotating shaft of the magnetic field generator is irrotationally fitted. The support is supported on the developing case using the fitting portion as a main-positioning portion.

An image forming apparatus includes a photosensitive member, a developing member to supply a toner to the photosensitive member at a developing portion, a transfer member to transfer a toner image to a recording material passing through a transfer portion from the photosensitive member. In a case which the transfer is performed to a smaller width recording material and thereafter, the transfer is successively performed to a larger width recording material, a control portion controls a first back contrast formed when an area of a surface of the photosensitive member corresponding to the transfer portion through which the smaller width recording material is passing reaches the developing portion, and a second back contrast formed when an area of the surface corresponding to the transfer portion through which the larger width recording material is passing reaches the developing portion so that the second back contrast is larger than the first back contrast.

In a case where a transfer roller is viewed from a direction orthogonal to a rotation axis direction of a shaft, the shaft includes in a longitudinal direction a first contact portion which is provided on an end portion side of an elastic portion and in which the shaft and the elastic portion are in contact with each other and a second contact portion which is provided on a more inner side than the first contact portion and in which the shaft and the elastic portion are in contact with each other. The transfer roller includes a void between the first contact portion and the second contact portion in the longitudinal direction, and the void is arranged at least on a more inner side than an end portion of a transfer material having a maximum size.

A region of an image bearing member that comes into contact with a recording material at a nip in a state in which the recording material is held by the nip is a first region, and a region of the image bearing member that does not come into contact with the recording material at the nip in a state in which the recording material is not held by the nip is a second region. A controller controls to apply a first developing voltage to a developer bearing member when the first region in which a first surface potential has been formed faces a developer bearing member and apply a second developing voltage lower than an absolute value of the first developing voltage to the developer bearing member when the second region in which a second surface potential has been formed faces the developer bearing member.

An intermediate transfer body includes a base layer and a surface layer disposed on the base layer, in which surface layer includes a sea-island structure that includes a sea phase and an island phase, in which the sea phase includes a resin, the island phase including an organopolysiloxane.

An image forming apparatus includes a rotatable photosensitive member; a charging portion, an exposure portion, a developing member, a transfer unit, a contact and separation portion, a charging voltage applying portion, a detecting portion, and a controller. The controller is capable of executing an operation in an image forming mode and an operation in a detecting mode. The controller carries out control so that a charging current flowing through a charging portion during charging of the photosensitive member in the operation in the detecting mode is lower than a charging current flowing through the charging portion during charging of the photosensitive member in the operation in the image forming mode.

It is an object of the present invention to provide an electrophotographic photosensitive member capable of suppressing the environmental fluctuation in the electrical characteristics. The present invention provides the electrophotographic photosensitive member in which the surface layer contains the compound having the specific structure.

An image forming apparatus includes a photoconductor, a charging section that charges a surface of the photoconductor, an electrostatic charge image forming section that forms an electrostatic charge image on the charged surface of the photoconductor, a developing section that accommodates a developer containing a toner and develops the electrostatic charge image formed on the surface of the photoconductor by using the developer to form a toner image, a transfer section that includes an endless belt and transfers the toner image to a recording medium; and a cleaning section that includes a cleaning blade that comes into contact with a surface of the endless belt and performs cleaning of the surface of the endless belt with the cleaning blade, in which a dynamic friction coefficient μ between the endless belt and the cleaning blade is 0.10 or more and 0.25 or less, and the endless belt has an outer peripheral surface on which an uncharged toner is scattered by a wind force of wind pressure of 23 kPa or smaller at a temperature of 22° C. and relative humidity of 55%.

An image forming apparatus includes a transferring belt, photosensitive drums along the belt, primary transferring parts transferring images from the drums to the belt, voltage applying parts applying transfer voltages to the respective transferring parts when each transferring part carries out transfer, a current detecting part and a resistance value measuring part. When the measuring part carries out resistance value measurement, if one transferring part is a measurement subject of the measuring part, the applying part applies zero or weak voltage to the one transferring part and applies the transfer voltage to other transferring parts at measurement timing when the one transferring part is between sheets. At the measurement timing, the detecting part detects a first total current value of currents flowing thorough the transferring parts and the measuring part measures the subject resistance value of the one transferring part based on the first total current value.

An image forming apparatus has an image carrier that carries a toner image; a transfer member that is opposed to the image carrier, a transfer voltage being applied to the transfer member so that the toner image is transferred from the image carrier to a print medium passing between the transfer member and the image carrier; a first voltage application device that applies the transfer voltage to the transfer member; a separation member to which a separation voltage is applied so that the print medium is separated from the image carrier; a second voltage application device that applies the separation voltage to the separation member; a sensing device that senses an image density of the toner image; and a control section that controls a magnitude of the separation voltage based upon the image density of the toner image.