Abstract: An image forming apparatus includes a detecting element that detects a temperature of a heat generating member, a counter that counts a value corresponding to a cumulative time in which an endless belt is heated, and a controller that controls a timing of a start of image formation by an image forming portion depending on an output of the detecting element. When the value counted by the counter corresponds to a first cumulative time, the controller starts the image formation at a first timing when the detecting element carries out an output corresponding to a first temperature, and, when the value counted by the counter corresponds to a second cumulative time longer than the first, the controller starts the image formation at a second timing when the detecting element carries out an output corresponding to a lower second temperature.

Abstract: An image forming apparatus in which generation of an image defect is suppressed is provided. A printer (1) includes an image forming portion (10), a belt (101) onto which a lubricant is applied at an inner surface, a pressing roller (106), a heater (100), a heater holder (103), a thermistor (111), a heat insulating member (113) for heat-insulating the thermistor and the heater holder, and a controller (45), and the controller starts an image forming operation at timing when the thermistor detected a first temperature during a warming-up process in the case where a time of energization to the heater is less than a predetermined time, and starts the image forming operation at timing when the thermistor detected a second temperature lower than the first temperature during the warming-up process in the case where the time of energization to the heater is not less than the predetermined time.

Abstract: An image heating device includes a belt, a light emitting portion, a light receiving portion, and a control portion. The belt heats an image on a sheet in an image heating operation. The light emitting portion emits light from one widthwise end of the belt to the other widthwise end of the belt such that the light passes near a peripheral surface of the belt. The light receiving portion receives the light from the light emitting portion. The control portion controls, according to an output of the light receiving portion, whether or not to prohibit the image heating operation.

Abstract: A fixing belt includes a cylindrical base composed of a metal and a polyimide resin layer formed on the inner peripheral surface of the cylindrical base, in which the polyimide resin layer has an imidization rate of 70% to 93%, and comprises a polyimide resin containing a specific constitutional unit.

Abstract: An image heating device includes a belt, a light emitting portion, a light receiving portion, and a control portion. The belt heats an image on a sheet in an image heating operation. The light emitting portion emits light from one widthwise end of the belt to the other widthwise end of the belt such that the light passes near a peripheral surface of the belt. The light receiving portion receives the light from the light emitting portion. The control portion controls, according to an output of the light receiving portion, whether or not to prohibit the image heating operation.

Abstract: The image heating apparatus has a plurality of heat generators which are capable of forming a plurality of heat generating distributions in the longitudinal direction for supplying heat to a heating member. Unevenness in temperature is decreased by changing the heat generating distribution when cooling by a fan for the heating member starts. The heat generating distribution is changed so that heat generating amount at an area in the longitudinal direction corresponding to the cooling area cooled by the fan is to be larger than the heat generating amount before starting the cooling.

Abstract: The image heating apparatus has a plurality of heat generators which are capable of forming a plurality of heat generating distributions in the longitudinal direction for supplying heat to a heating member. Unevenness in temperature is decreased by changing the heat generating distribution when cooling by a fan for the heating member starts. The heat generating distribution is changed so that heat generating amount at an area in the longitudinal direction corresponding to the cooling area cooled by the fan is to be larger than the heat generating amount before starting the cooling.

Abstract: The image heating apparatus has a plurality of heat generators which are capable of forming a plurality of heat generating distributions in the longitudinal direction for supplying heat to a heating member. Unevenness in temperature is decreased by changing the heat generating distribution when cooling by a fan for the heating member starts. The heat generating distribution is changed so that heat generating amount at an area in the longitudinal direction corresponding to the cooling area cooled by the fan is to be larger than the heat generating amount before starting the cooling.

Abstract: A fixing belt includes a cylindrical base composed of a metal and a polyimide resin layer formed on the inner peripheral surface of the cylindrical base, in which the polyimide resin layer has an imidization rate of 70% to 93%, and comprises a polyimide resin containing a specific constitutional unit.

Abstract: The image heating apparatus has a plurality of heat generators which are capable of forming a plurality of heat generating distribution in the longitudinal direction for supplying heat to a heating member. Unevenness in temperature is decreased by changing the heat generating distribution when cooling by a fan for the heating member starts. The heat generating distribution is changed so that heat generating amount at an area in the longitudinal direction corresponding to the cooling area by the fan is to be larger than the heat generating amount before starting the cooling.

Abstract: An image heating apparatus includes a first belt contactable to an image on a recording material to heat the image; a second belt for forming a nip with the first belt; a first pressing pad for pressing the first belt in the nip; a second pressing pad for pressing the second belt toward the first pressing pad, wherein the first pressing pad has a surface roughness Rz of not more than 20 ?m, and the second pressing pad has a surface roughness Rz of 50-300 ?m.

Abstract: An image heating apparatus includes a rotatable heating member configured to heat an image on a recording medium at a nip, driving means configured to drive the heating member, an endless belt configured to form the nip with the heating member, and a driving roller configured to drive the endless belt. In the image heating apparatus, the following expressions are satisfied: ?2<?1 0.005<?2<0.3 V1<V2 where ?2 is a friction coefficient between the endless belt and the driving roller, ?1 is a friction coefficient between the heating member and the endless belt, V1 is a peripheral speed of the heating member, and V2 is a peripheral speed of the driving roller.

Abstract: An image heating apparatus includes a rotatable heating member configured to heat an image on a recording medium at a nip, driving means configured to drive the heating member, an endless belt configured to form the nip with the heating member, and a driving roller configured to drive the endless belt. In the image heating apparatus, the following expressions are satisfied: ?2<?1 0.005<?2<0.3 V1<V2 where ?2 is a friction coefficient between the endless belt and the driving roller, ?1 is a friction coefficient between the heating member and the endless belt, V1 is a peripheral speed of the heating member, and V2 is a peripheral speed of the driving roller.

Abstract: An image heating apparatus includes a first belt contactable to an image on a recording material to heat the image; a second belt for forming a nip with the first belt; a first pressing pad for pressing the first belt in the nip; a second pressing pad for pressing the second belt toward the first pressing pad, wherein the first pressing pad has a surface roughness Rz of not more than 20 ?m, and the second pressing pad has a surface roughness Rz of 50-300 ?m.

Abstract: An object of the present invention is to provide a fixing apparatus that has a fixing rotating member for holding and conveying a recording material supporting an unfixed image to perform fixation, driving device for driving the fixing rotating member, a cleaning rotating member for cleaning the fixing rotating member, and contact/separation device for bringing the cleaning rotating member into contact with and away from the fixing rotating member, wherein the driving device drives the fixing rotating member at a predetermined fixing speed during fixation and at a cleaning speed lower than the fixing speed at the time of cleaning by the cleaning rotating member.

Abstract: An object of the present invention is to provide a fixing apparatus that has a fixing rotating member for holding and conveying a recording material supporting an unfixed image to perform fixation, driving device for driving the fixing rotating member, a cleaning rotating member for cleaning the fixing rotating member, and contact/separation device for bringing the cleaning rotating member into contact with and away from the fixing rotating member, wherein the driving device drives the fixing rotating member at a predetermined fixing speed during fixation and at a cleaning speed lower than the fixing speed at the time of cleaning by the cleaning rotating member.

Abstract: A fixing device and an image forming apparatus having such a device is constructed by an unfixed image forming unit to form an unfixed image onto a recording material in accordance with start of an image formation, a heater in which a heat generating material which generates a heat by an energization is provided on a substrate, the unfixed image formed by the unfixed image forming unit being heated and fixed onto the recording material by a heat from the heater, and a power supplying unit for supplying an electric power to the heater in a first mode with a first maximum power by the start of the image formation and, subsequently, for supplying an electric power to the heater in a second mode with a second maximum power. The first maximum power is smaller than the second maximum power. In both of the first and second modes, the powers are controlled so that the heater is set to a predetermined temperature.