Abstract: An image forming apparatus includes: an image bearing member for bearing a toner image; a belt for conveying the toner image; and a transfer device for rubbing the belt, and a surface of the transfer device, which is brought into contact with the belt includes linear concave portions or linear convex portions. The image forming apparatus of the present invention prevents a friction force between the belt and the transfer device rubbing the belt from increasing and brings a transfer member into a stable contact with the belt for conveying the toner image, thereby suppressing increase in drive torque of the belt which rubs the transfer device and suppressing occurrence of image failure.

Abstract: An image forming apparatus includes: an image bearing member for bearing a toner image; a belt for conveying the toner image; and a transfer device for rubbing the belt, and a surface of the transfer device, which is brought into contact with the belt includes linear concave portions or linear convex portions. The image forming apparatus of the present invention prevents a friction force between the belt and the transfer device rubbing the belt from increasing and brings a transfer member into a stable contact with the belt for conveying the toner image, thereby suppressing increase in drive torque of the belt which rubs the transfer device and suppressing occurrence of image failure.

Abstract: An image heating apparatus for heating a toner image formed on a recording material includes a first rotatable member contactable to the toner image; and a heating unit, including a second rotatable member rotating while contacting a surface of the first rotatable member, for heating the first rotatable member. The toner image on the recording material is heated by receiving heat from the first rotatable member heated by the heating unit. The image heating apparatus further includes a potential controller for maintaining a polarity of a surface potential of the second rotatable member so as to be opposite to a charge polarity of the toner.

Abstract: The present invention is directed to suppressing cracks in the surface layer of the rotating member including fluororesin. According to the present invention, there is provided a heating apparatus comprising: a rotating member which has a surface layer comprising fluororesin, flexibility, and is open at both ends thereof; a heating member for heating the rotating member; a holding member for the rotating member, which is disposed inside the rotating member and has a sliding surface against an inner peripheral surface of the rotating member; and a pressurizing member for forming a nip portion together with the rotating member, the heating apparatus heating a recording material while conveying the recording material by nipping at the nip portion and rotating the rotating member and the pressurizing member, wherein a lubricant comprising a straight-chain and a side-chain type perfluoropolyethers is interposed between the rotating member and the sliding surface of the holding member.

Abstract: An image forming apparatus includes: an image bearing member for bearing a toner image; a belt for conveying the toner image; and a transfer device for rubbing the belt, and a surface of the transfer device, which is brought into contact with the belt includes linear concave portions or linear convex portions. The image forming apparatus of the present invention prevents a friction force between the belt and the transfer device rubbing the belt from increasing and brings a transfer member into a stable contact with the belt for conveying the toner image, thereby suppressing increase in drive torque of the belt which rubs the transfer device and suppressing occurrence of image failure.

Abstract: An image forming apparatus includes: an image bearing member for bearing a toner image; a belt for conveying the toner image; and a transfer device for rubbing the belt, and a surface of the transfer device, which is brought into contact with the belt includes linear concave portions or linear convex portions. The image forming apparatus of the present invention prevents a friction force between the belt and the transfer device rubbing the belt from increasing and brings a transfer member into a stable contact with the belt for conveying the toner image, thereby suppressing increase in drive torque of the belt which rubs the transfer device and suppressing occurrence of image failure.

Abstract: An image forming apparatus for forming image on a recording medium includes a photosensitive member, a motor, a belt, and a drive member to rotate the belt, the drive member including a driven coupling. The apparatus also includes a drive coupling to rotate by a driving force generated by the motor, the drive coupling being movable in an axial direction to take an engagement position at which the driving force is transmittable to the driven coupling, and a release position. The apparatus further includes a transfer member to transfer a toner image onto the recording medium or the belt, a voltage application unit to apply a voltage to the transfer member, and a control unit to cause the voltage application unit to apply the voltage to the transfer member after the drive coupling moves to the engagement position and the driving force is transmitted to the driven coupling.

Abstract: A fixing roller has a base layer, a rubber layer formed on the base layer and a surface layer formed of a fluororesin tube, and a heater disposed inside the roller. The surface layer of the roller is formed by covering the fluororesin tube on the rubber layer in a condition where the fluororesin tube is pulled in a radial direction of the fluororesin tube, the fluororesin tube has an internal diameter less than an outer diameter of the roller and a thickness of 20 microns or smaller and a crystallization degree of the fluororesin tube being 50% or smaller. The roller is made by expanding the fluororesin tube is in a radial direction and drawing the fluororesin tube in a generatrix direction thereof, wherein a drawing ratio of the fluororesin tube in the drawing the fluororesin tube in the generatrix direction is 5% or smaller.

Abstract: An image forming apparatus includes an image forming portion for forming an unfixed toner image on a recording material; and a fixing portion for heat-fixing the unfixed toner image on the recording material while nip-conveying the recording material in a fixing nip, the fixing portion includes a first rotatable member contactable to the unfixed toner image, and a second rotatable member contacted to the first rotatable member to form the fixing nip between itself and the first rotatable member. The image forming apparatus is capable of setting a cleaning mode in which the fixing portion is cleaned by a cleaning sheet while nip-conveying the cleaning sheet in the fixing nip. When the cleaning mode is set, the image forming apparatus executes a plurality of types of cleaning operations in a period in which a single cleaning sheet passes through the fixing nip.

Abstract: An image forming apparatus is capable of setting a cleaning mode in which a fixing portion is cleaned by a cleaning sheet while nip-conveying the cleaning sheet in a fixing nip. When the cleaning mode is set, an image forming apparatus provides a period in which a first rotatable member and a second rotatable member are rotated in a state in which a heater is controlled so that a surface temperature Th of the first rotatable member immediately after passing through the fixing nip is kept within a temperature range of Th?Tf3, wherein Tf3 is a flow start point of a toner and so that a surface temperature Tp of the second rotatable member immediately after passing through the fixing nip is within a temperature range Tf2?Tp?Tf3, wherein Tf2 is a deformation end point of the toner.

Abstract: An image forming apparatus for forming image on a recording medium includes a photosensitive member, a motor, a belt, and a drive member to rotate the belt, the drive member including a driven coupling. The apparatus also includes a drive coupling to rotate by a driving force generated by the motor, the drive coupling being movable in an axial direction to take an engagement position at which the driving force is transmittable to the driven coupling, and a release position. The apparatus further includes a transfer member to transfer a toner image onto the recording medium or the belt, a voltage application unit to apply a voltage to the transfer member, and a control unit to cause the voltage application unit to apply the voltage to the transfer member after the drive coupling moves to the engagement position and the driving force is transmitted to the driven coupling.

Abstract: An image forming apparatus includes an image bearing member for bearing a toner image; an endless rotatable intermediary transfer belt onto which the toner image is to be transferred from the image bearing member; a transfer device disposed at a position in which the transfer device opposes the image bearing member through the intermediary transfer belt, the transfer device including a sheet member surface-contacted to an inner surface of the intermediary transfer belt and including an urging member for urging the sheet member toward the intermediary transfer belt; and a primary transfer voltage source for applying a voltage to the sheet member.

Abstract: An image forming apparatus for forming image on a recording medium includes a photosensitive member, a motor, a belt, and a drive member to rotate the belt, the drive member including a driven coupling. The apparatus also includes a drive coupling to rotate by a driving force generated by the motor, the drive coupling being movable in an axial direction to take an engagement position at which the driving force is transmittable to the driven coupling, and a release position. The apparatus further includes a transfer member to transfer a toner image onto the recording medium or the belt, a voltage application unit to apply a voltage to the transfer member, and a control unit to cause the voltage application unit to apply the voltage to the transfer member after the drive coupling moves to the engagement position and the driving force is transmitted to the driven coupling.

Abstract: An apparatus includes an image bearing member for carrying an image; an intermediary transfer member for receiving the image; a primary transfer member for transfer of the image onto the intermediary transfer member in a primary transfer station; a secondary transfer member for transfer of the image onto a transfer material in a secondary transfer station; a first charging member for charging toner remaining in a region upstream of the primary transfer station and downstream of the secondary transfer station; and a second charging member for charging the toner remaining in a region upstream of the primary transfer station and downstream of the first charging member. The first charging member rubs a surface of, and the second charging member moves in contact with, the intermediary transfer member, to transfer the toner remaining on the intermediary transfer member to the image bearing member simultaneously with the primary transfer.

Abstract: An image forming apparatus includes: an image bearing member for bearing a toner image; a belt for conveying the toner image; and a transfer device for rubbing the belt, and a surface of the transfer device, which is brought into contact with the belt includes linear concave portions or linear convex portions. The image forming apparatus of the present invention prevents a friction force between the belt and the transfer device rubbing the belt from increasing and brings a transfer member into a stable contact with the belt for conveying the toner image, thereby suppressing increase in drive torque of the belt which rubs the transfer device and suppressing occurrence of image failure.

Abstract: A fixing apparatus, a roller for a fixing apparatus, and a flexible sleeve for a fixing apparatus are a roller for the fixing apparatus (1) having a rubber layer (1b) and a fluororesin tube as a surface layer (1c) covered thereon. A thickness of the fluororesin tube is 20 microns or smaller, and a crystallization degree of the fluororesin tube is 50% or smaller. Thus, in the roller for the fixing apparatus having the rubber layer on which the resin tube is covered as the surface layer, a crack does not occur in the fluororesin tube even if the fluororesin tube is made thin.