According to one embodiment, an image forming apparatus includes a sheet supply unit, a printer, a fixing device, and a controller. The sheet supply unit supplies a sheet from a sheet container. The printer forms a toner image to the sheet conveyed from the sheet supply unit. The fixing device includes a heater, a fixing belt, and a pressure roller. The heater includes a heat generating member including a plurality of heating elements arranged in a first direction orthogonal to a sheet conveyance direction and in which a heating element group selected in response to a printing request from the heat generating member generates heat. The fixing belt fixes the toner image heated by the heater to the sheet. The pressure roller presses the fixing belt.

According to one embodiment, a heating device includes a cylindrical belt, a heat generating member, and a support member. The heat generating member is disposed in an interior region surrounded by the belt and in contact with an inner peripheral surface of the belt. The support member is provided in the interior region surrounded by the belt and contacts and supports the heat generating member.

A fixing device includes a heater, a first rotatable member, a second rotatable member, and a heat equalizing member. In a case that a region including a center of the heat equalizing member with respect to a longitudinal direction is a first region, a region closer to an end of the heat equalizing member than the first region is with respect to the longitudinal direction is a second region, and a region closer to the end of the heat equalizing member than the second region is with respect to the longitudinal direction is a third region. When the heat equalizing member has thermal capacities per unit length in the first region, the second region, and the third region are Cα, Cβ and Cγ, respectively, Cα, Cβ and Cγ satisfy the following relationship:
Cα>Cβ, and Cγ>Cβ.

Provided is an endless belt that can be used for fusing a toner image or enhancing the gloss of a toner image, the endless belt including a substrate later and a release layer on the substrate layer. The release layer can include a coating layer that includes an inorganic-organic nanocomposite material in which inorganic nanoparticles are dispersed in a siloxane polymer matrix.

A device to prevent fire of a fusing belt having a heater positioned inside includes at least one temperature control member adjacent to one side of the fusing belt and, when the at least one temperature control member detects abnormal heat from the fusing belt based on a temperature of the fusing belt, the at least one temperature control member to cut off a supply of electricity to the heater to prevent the fire. The device also includes a heat absorption member adjacent to the other side of the fusing belt and to absorb latent heat from the fusing belt to lower the temperature of the fusing belt to prevent the fire.

An electroconductive elastic body includes: a cross-linked product of a first ionic electro-conductive rubber, a cross-linked product of a second ionic electro-conductive rubber, and at least one of a fatty acid and a fatty acid metal salt; wherein the electroconductive elastic body has a matrix that includes the cross-linked product of the first ionic electro-conductive rubber, and a domain that includes the cross-linked product of the second ionic electro-conductive rubber; the cross-linked product of the second ionic electro-conductive rubber includes a polyether skeleton; an electrical resistance of the domain is lower than an electrical resistance of the matrix; in a waveform separation profile of the elastic body as obtained by a small-angle X-ray scattering method, A2 and A1 satisfy a relationship expressed by the following expression (1):
0.005≤(A2×C2/A1×C1)≤0.030  (1).

An image forming apparatus includes: a transfer cylinder that is supported on an image forming apparatus body and rotates; a rotating member that is coaxial with the transfer cylinder and rotates integrally with the transfer cylinder; a circulating member that is provided with a holding part that holds a front end portion of a recording medium, is suspended around the rotating member, and transports the recording medium by circulating as the rotating member rotates; a transfer unit that is supported on the image forming apparatus body and has a transfer belt that transfers an image on a recording medium transported by the circulating member by sandwiching the recording medium together with the transfer cylinder at a nip position; a first image forming part that is supported on the image forming apparatus body and forms the image on the transfer belt; and a second image forming part that is supported on the image forming apparatus body at a position lower than the first image forming part and forms the image on the transfer belt. Mass of the second image forming part is larger than mass of the first image forming part.

A heating device (9) includes a heater (22), a holder (23), a device frame (40), a primary positioner (A), a secondary positioner (B), and a tertiary positioner (C). The heater includes a heat generator (60). The holder holds the heater. The device frame is configured to support the holder. The primary positioner is configured to position the heater and the holder in a longitudinal direction of the heater. The secondary positioner is configured to position the holder and the device frame in the longitudinal direction of the heater. The tertiary positioner is configured to position the device frame and a body of an image forming apparatus in the longitudinal direction of the heater. The primary positioner and one of the secondary positioner and the tertiary positioner are disposed on an identical side defined by a center of the heat generator in the longitudinal direction of the heater.

The present invention is characterized in that a control portion respectively sets a heating amount with respect to a region in which an image is formed and a heating amount with respect to a region in which an image is not formed in a single sheet of a recording material, and a difference between the heating amount with respect to the region in which an image is formed and the heating amount with respect to the region in which an image is not formed differs depending on a type of the recording material.

A fixing unit includes a film including a tubular shape and configured to rotate, a heater arranged inside the film and including a heating resistor configured to generate heat by passing alternating current therethrough and an insulator configured to cover the heating resistor, a sliding member arranged between the heater and the film and configured to be in sliding contact with an inner surface of the film, the sliding member having electric conductivity, a pressing member configured to be in pressure contact with the sliding member across the film to form a nip portion between the sliding member and the pressing member, and a conductive member electrically connected to a ground potential via at least one impedance element. The sliding member is electrically connected to the conductive member.