Provided is an electrophotographic belt of an endless shape including a substrate, wherein the substrate contains a polyimide resin and carbon nanotubes, wherein a content of the carbon nanotubes in the substrate is 15 vol % or less with respect to a total volume of the polyimide resin, wherein the substrate has a tensile strength of 200 MPa or more in each of a peripheral direction thereof and a direction perpendicular to the peripheral direction, and wherein the substrate has a thermal conductivity of 0.9 W/(m.Math.K) or more in a thickness direction thereof.

A belt includes a resin and an aggregate in which plural fibrous carbons are entangled with each other, in which a maximum diameter of the aggregate is 50% or less of a belt film thickness.

Provided is a fixing apparatus that fixes an unfixed image on a sheet by causing the sheet to pass through a fixing nip formed by pressing a belt by a pressurizing roller, a lubricant being applied on an inner peripheral surface of the belt, the pressurizing roller being disposed on an outer peripheral side of the belt, and the fixing apparatus includes: a non-rotary pad including a pressed part disposed on an inner peripheral side of the belt and pressed by the pressurizing roller via the belt, and a guide that is disposed upstream of the pressed part in a belt circulating direction and guides the belt to the fixing nip; and a pressure application part that applies a pressure between an end of the belt in a belt width direction and the guide at a position upstream of and immediately before the fixing nip in the belt circulating direction.

A fixing device includes a rotatable endless belt; a planar heat-generating section in which at least a downstream end portion in a movement direction of the belt is in pressure contact with a rotating body via a pressure contact portion and a cross-sectional shape of a downstream edge portion being in contact with an inner surface of the belt is formed in a curved shape having a curvature radius of 0.01 mm or more 0.2 mm or less or in a shape in which the edge portion is cut out over the dimension; and a holding section that is disposed inside the belt and holds the planar heat-generating section to be in pressure contact with the rotating body.

A fixing device includes a movable belt; and a planar heat-generating section that is in contact with the belt and in which, among plural heat-generating portions provided in a movement direction of the belt, a heat-generating portion on an upstream side in the movement direction of the belt has a larger heat generation amount than a heat-generating portion on a downstream side.

A fixing belt includes, in the following order: a resin base material layer; an elastic layer; and a release layer, in which the elastic layer contains an elastic material and an aggregate in which plural fibrous carbons are entangled with each other, and a maximum diameter of the aggregate is 15% or less of a film thickness of the elastic layer.

A fixing belt includes, in the following order: a base material layer containing a resin; an elastic layer containing an elastic material; and a release layer, in which each of the base material layer and the elastic layer further contains an aggregate in which plural fibrous carbons are entangled with each other, a maximum diameter of the aggregate in the base material layer is 50% or less of a film thickness of the base material layer, and a maximum diameter of the aggregate in the elastic layer is 15% or less of a film thickness of the elastic layer.

A heating device includes a heating roller having a resistance heat-generating layer that generates heat by passage of a current through the resistance heat-generating layer, a support member that supports a treatment portion in which a heating treatment is performed, a belt that is stretched between at least the heating roller and the support member and that rotates, and a pressure rotating body that rotates in such a manner as to press a sheet-shaped heating target that is an object to be subjected to a heating treatment against the treatment portion including an outer peripheral surface portion of the belt that is supported by the support member and in such a manner as to cause the heating target to pass through the treatment portion. The heating roller is not equipped with a power receiving component configured to receive a rotational power that is transmitted.

An image forming apparatus is operable in a first small-sheet printing in which power is supplied to the first heat generating element and the second heat generating element and in a second small-sheet printing in which power is supplied to the first heat generating element and the third heat generating element. A first power ratio, which is a proportion of power supplied to the first heat generating element to power supplied to the second heat generating element in the first small-sheet printing, is higher than a second power ratio, which is a proportion of power supplied to the first heat generating element to power supplied to the third heat generating element in the second small-sheet printing.

In an image forming device, a first fixing member has a roller. A second fixing member has a belt to form a nip together with the first fixing member. A first motor drives the roller. A pressure modifying mechanism modifies a nip pressure at the nip to selected one of a first nip pressure and a second nip pressure smaller than the first nip pressure. A controller starts driving the first motor to drive the roller in a case where a print command is received in a state that the nip pressure is the second nip pressure. The controller modifies the nip pressure from the second nip pressure to the first nip pressure after the driving is performed and fixes the developer image on the sheet in a state that the nip pressure is the first nip pressure.