An image forming apparatus includes at least one upper image forming unit in which an image holding unit is disposed above a transfer unit in such a manner as to face the transfer unit with a transfer medium, which moves in a predetermined direction, interposed between the image holding unit and the transfer unit and at least one lower image forming unit in which an image holding unit is disposed below a transfer unit in such a manner as to face the transfer unit with the transfer medium interposed between the image holding unit and the transfer unit, the transfer unit of the upper image forming unit and the transfer unit of the lower image forming unit each including a transfer member that extends in a width direction crossing the direction of movement of the transfer medium and that is brought into contact with the transfer medium and a pressing unit that presses the transfer member toward the image holding unit, and the pressing units being set in such a manner that a pressing force that is applied by one of the pressing units to the transfer member of the upper image forming unit is larger than a pressing force that is applied by another one of the pressing units to the transfer member of the lower image forming unit in a direction that makes pressing loads of the transfer members against the image holding units equal.

An image forming apparatus includes an image forming portion, a transfer belt, a secondary transfer portion, a cleaning member contacting a surface of the transfer belt for cleaning the surface of the transfer belt, a fixing device, an exhausting device, a duct portion and a sheet member. The sheet member is provided on the exhausting device so as to project toward the transfer belt from the exhausting device, the sheet member being opposed to transfer belt and separated by a predetermined space downstream of the transfer portion and upstream of the cleaning member with respect to a rotational direction of the transfer belt, and being configured to prevent air flow between the exhausting device and the transfer belt from flowing downstream with respect to the rotational direction.

An image forming device comprising circuitry. The circuitry generates an image pattern in which two or more types of patch images are combined and changes a value of image data around at least one type of patch image of the two or more types of patch images to less than a maximum value of image data of the at least one type of patch image when the two or more types of patch images are combined.

A transfer device includes a transfer roller and a transfer counter roller. The transfer roller has an elastic layer, contacts with and separates from an image bearer including a belt-shaped elastic body, and nips a recording medium with the image bearer. The transfer counter roller has an elastic layer, is disposed facing the transfer roller, and nips the image bearer with the transfer roller. The transfer counter roller or the transfer roller is applied with a bias to transfer the toner image. Each of the elastic layers of the transfer roller and the transfer counter roller has an Asker C hardness of 75 or less. A difference in thickness between the elastic layers of the transfer roller and the transfer counter roller is ±3% or less.

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 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 includes a chassis having an opening, a cover, photosensitive members, an intermediate transfer belt, a primary-transfer member, a secondary-transfer roller, a cleaner device, an external-sheet inlet, a waste toner container, a connector, and a conveying roller, which is arranged within the feeding path to feed the recording sheet inserted through the external-sheet inlet in the feeding path. The conveying roller is mounted on the waste toner container and removable from the chassis along with the waste toner container.

A belt conveyance apparatus includes a plurality of support rollers, an endless belt, a regulation portion configured to regulate a shift of the endless belt in a width direction, a regulation receiving member configured to contact the regulation portion to receive a regulation force by the regulation portion, and support members disposed on an upstream side, in a conveyance direction of the endless belt, of the support rollers provided with the regulation portion to oppose each other on an inner peripheral surface side and an outer peripheral surface side of the end portion side of the endless belt in the width direction, and configured to regulate a position of the regulation receiving member when the regulation receiving member enters a contact portion with the regulation portion.

An image forming apparatus has an image carrier carrying a toner image; a transfer member made with an ion conductive material and forming a transfer nip by being pressed by the image carrier; and a power supply continuously applying a transfer bias voltage to the transfer member as a plurality of print media pass through the transfer nip. The transfer bias voltage has a predetermined polarity. A control section determines whether the resistance of a nip-margin area has exceeded a predetermined resistance threshold, the nip-margin area being a marginal portion of the transfer nip through which no print medium passes. When the determination of the control section is affirmative, the power supply applies a reverse-bias voltage to the transfer member, the reverse-bias voltage having an opposite polarity to the transfer bias voltage.

An image forming apparatus that includes an image bearing member which can bear a toner image, a transfer member used to transfer a toner image onto a recording material from the image bearing member, and a reading device which reads density information of images on recording material disposed on a platen. The image forming apparatus forms a first chart on a first recording material and a second chart on a second recording material by sequentially transferring a plurality of test images while applying a plurality of test voltages to the transfer member. The two charts are read by the reading device and the transfer voltage is adjusted based on the reading result.