A fixing belt and a fixing device suppress charging of the fixing belt and permit securing of a withstand voltage of secondary parts of the fixing belt are provided in addition to a heater. The fixing belt is formed of a tubular endless fixing film including, in order from an inner peripheral side of the film, abase layer, an elastic layer, and a release layer. A surface resistivity of the fixing belt measured from the base layer side is 7 [LOG Ω/sq.] or more and 10 [LOG Ω/sq.] or less.

An image heating apparatus includes a first rotating member, a second rotating member to form a nip portion which sandwiches a recording material between the first rotating member and the second rotating member, a heater unit provided inside the first rotating member and having a heater for heating an image on the recording material sandwiched by the nip portion, and a sheet member provided to overlap a part of the heater and electrically connected to the heater. The sheet member includes a first sheet member connected to one end of the heater in a longitudinal direction of the heater and a second sheet member connected to the other end of the heater, the first sheet member extends from the one end of the heater in a direction crossing the longitudinal direction, and the second sheet member extends from the other end of the heater in the longitudinal direction.

A fixing device includes a fixing rotator over which a recording medium bearing an image is conveyed. A first heater heats the fixing rotator and generates heat evenly in a maximum conveyance span where the recording medium having a maximum width in a width direction of the recording medium is conveyed. The maximum width is available for the fixing rotator. A second heater heats the fixing rotator and generates heat in the maximum conveyance span. The second heater includes a first portion that generates heat in a first heat generation amount and a second portion that generates heat in a second heat generation amount that is greater than the first heat generation amount of the first portion.

A fixing device includes a fixing belt that is endless and rotatable. A nip formation pad is disposed opposite an inner circumferential face of the fixing belt via a lubricant. A pressure roller sandwiches the fixing belt together with the nip formation pad to form a pressing region through which a recording medium is conveyed. A cap is disposed opposite a lateral end of the fixing belt in an axial direction of the fixing belt. A seal is tubular and contacts an outer circumferential face of the fixing belt in at least a part of an inner circumferential face of the seal. The seal seals a gap between the cap and the fixing belt. The seal includes a non-perpendicular portion that is not perpendicular to a circumferential direction of the fixing belt and defines a slit.

A belt device includes a belt, a secured member, a pressure rotator, and lubricant. The belt is rotatable and has an endless shape. The belt includes an inner portion having an inner circumferential surface. The inner portion has an elastic power of 55% or more. The inner circumferential surface of the belt slides on the secured member. The pressure rotator includes a porous elastic body and presses the secured member via the belt to form a nip between the belt and the pressure rotator. The lubricant is interposed between the inner circumferential surface of the belt and the secured member.

A rotator driver includes an endless rotator having an end face in a longitudinal direction thereof. A slide aid contacts an inner circumferential face of the endless rotator. A lubricant is applied between the slide aid and the inner circumferential face of the endless rotator. An end face contact member contacts the end face of the endless rotator and has an end face opposed face contacting the end face of the endless rotator and an opposite face being opposite to the end face opposed face. A helical gear is mounted on the opposite face of the end face contact member. The helical gear has teeth being oriented to generate a force that moves the end face contact member toward the end face of the endless rotator as the helical gear rotates. The helical gear has an outer diameter being not greater than an outer diameter of the endless rotator.

A heater includes: a substrate; an insulating layer that is provided on the substrate; and a heat generating element that is provided on the insulating layer, and in a case where a region including a center of the substrate is defined as a first region, a region on a side closer to one end portion than the first region is defined as a second region, and a region on a side closer to the other end portion than the first region is defined as a third region in a transverse direction that is orthogonal to a longitudinal direction of a surface of the substrate on which the insulating layer is provided, the first region is a plane, and the second region and the third region are bent from the first region in a thickness direction of the substrate that is orthogonal to the longitudinal direction and the transverse direction.

A fixing member for electrophotography having an endless shape has a base layer having an endless shape, and an elastic layer on the outer circumferential surface of the base layer. The elastic layer includes a silicone rubber and a filler dispersed in the silicone rubber. The total amount of the filler compounded in the elastic layer is 30 vol % or less based on the total volume of the elastic layer. The elastic layer satisfies the relation of λtd>λmd>λnd. λtd is a thermal conductivity of the elastic layer in the circumferential direction, λnd is a thermal conductivity of the elastic layer in the thickness direction, and λmd, is a thermal conductivity of the elastic layer in the longitudinal direction. λtd is 2.0 W/(m.Math.K) or more, and λnd is 1.3 W/(m.Math.K) or more.

According to an embodiment, a heating device includes a cylindrical belt, a heater, a press roller, and a holder. The heater is disposed on an inner surface of the belt. The press roller rotates and is configured to contact an outer surface of the belt at a position opposite the heater to form a nip. The end portions of the press roller project by a first amount in a radial direction more than the central portion of the press roller. A holder has a first surface supporting the heater to face the cylindrical belt. The holder has a second surface that is opposite of the first surface with a center portion projecting in a direction orthogonal to the first surface more than the end portions of the second surface by a second projection amount that is greater than the first projection amount.

A heating device includes a heating unit that heats a member to be heated, which is transported, as a result of a contact portion of the heating unit being in contact with the member to be heated, a heat pipe that is disposed on a portion of the heating unit different from the contact portion in such a manner as to extend in a widthwise direction crossing a transport direction of the member to be heated and that includes a crimped portion formed at a first end of the heat pipe, a rotating body that rotates in such a manner as to press the member to be heated against the contact portion of the heating unit, and a power input unit that is disposed on a second end side of the heat pipe and that inputs a rotational force at least to the rotating body.