An image processing apparatus includes a fixing unit including a belt, and a heater configured to heat the belt and including a substrate and a heating layer that is formed on the substrate, and a controller configured to shut off the heater if no current flows through the belt.

A fuser has a heater, a heat roller, an endless belt, a pressure pad, and a slidable sheet. The pressure pad forms a nipping portion to nip the endless belt between the pressure pad and the heat roller. The slidable sheet is interposed between an inner circumferential surface of the endless belt and the pressure pad in the nipping portion. The slidable sheet includes a plurality of dents and a plurality of projections on a surface contacting the inner circumferential surface of the endless belt. The plurality of dents are arranged in a first part of the surface of the slidable sheet. The first part is located in a range corresponding to the nipping portion. The plurality of projections are arranged in a second part of the surface of the slidable sheet. The second part is located in a range corresponding to a portion different from the nipping portion.

A belt device includes an endless belt, a plurality of support rotators configured to support the endless belt, and a support configured to support shaft portions of the plurality of support rotators. The support has an attaching and detaching path through which the shaft portions of the plurality of support rotators pass in a direction orthogonal to an axial direction of at least one of the plurality of support rotators when the shaft portions of the plurality of support rotators are detached from the support.

An image heating apparatus includes a rotatable endless belt; a rotatable member, a plate-like heater, a holding member, a connector, movable in a first direction and a fixing member. The fixing member is mountable to and dismountable from the connector and the holding member by being moved in a second direction different from the first direction. The fixing member is mountable after the connector is mounted to the heater and the holding member, and the connector is dismountable after the fixing member is dismounted from the holding member.

A heater includes an insulator substrate, a heat generating section in which a plurality of divided regions are formed in a longitudinal direction on a first surface of the insulator substrate, electrodes formed at both end portions of the heat generating section to correspond to the plurality of divided regions, and electric conductors connected to at least one of the electrodes and formed over a surface different from the first surface of the insulator substrate.

A heating device for an image forming unit includes a heater unit, a cylindrical film, a support member, a first heat transfer unit, and a second heat transfer unit. The cylindrical film is at least partially disposed around the heater unit. The support member is configured to support the heater unit above the cylindrical film and such that the heater unit is located between the support member and the cylindrical film. The first heat transfer unit is disposed between the cylindrical film and the heater unit and in confronting relation with a first surface of the heater unit. The first heat transfer unit has a first contact area with the heater unit. The second heat transfer unit is disposed between the heater unit and the support member and in confronting relation with a second surface of the heater unit. The second surface is opposite the first surface.

A fixing device includes a cylindrical film, a support member disposed on an inner peripheral surface of the film, a heating member supported by the support member and provided slidably with the film, and a pressing member that forms a pressure contact portion together with the heating member through the film. The fixing device heats a recording medium while pressing the recording medium at the pressure contact portion. A first thermally conductive member and a second thermally conductive member are provided between the heating member and the support member. The first and second thermally conductive members having thermal conductivity higher than that of the support member are configured to engage with each other.

A fusing device includes an annular belt, a heat generation member arranged inside the annular belt, and a heat transmission member that has first and second faces, wherein the first face opposes the heat generation member and the second face opposes the annular belt, and the heat transmission member transmits heat to the annular belt, wherein the heat transmission member satisfies the following Conditional Expression (1):

D/L≥0.18×S−28  (1) where D means a thermal diffusivity [×10.sup.−6 m.sup.2/s] that is determined along the first face of the heat transmission member, L means a half of an interval [×10.sup.−3 m] between two of the heat generation parts adjacent to one another, and S: the carrying speed [×10.sup.−3 m/s] at which the medium is carried.

A fuser having a heater, a belt, and a holder, is provided. The heater includes a metal-made base plate and a resistive-heating element and has a first face and a second face. The resistive-heating element is formed on at least one of the first face and the second face. The belt being an endless belt has an inner circumferential surface contacting the first face of the heater and rotates around the heater. The holder has a retainer face to contact the second face of the heater to retain the heater and a belt-guiding face to contact the inner circumferential surface of the belt and guide the belt there-along. The base plate has a pair of first edges located on one end and the other end of the first face in the widthwise direction extending in the lengthwise direction. The pair of first edges are rounded at ridges.

An image heating apparatus includes an image heating portion including a heater, a tubular film having an inner surface in contact with the heater, and a pressure member that is in contact with the outer surface of the film and forms a nip portion for conveying a recording material between the outer surface and the pressure member. The image heating portion heats an unfixed toner image on the recording material by the heater. A temperature detection portion detects the temperature of the heater. A control portion controls electric power to the heater such that the temperature detected by the temperature detection portion is maintained at a predetermined control target temperature. An obtainment portion obtains image information for forming the unfixed toner image. The control target temperature is set, based on the image information, for each of a plurality of regions defined by dividing the recording material in the conveying direction.