An image forming apparatus includes a first determining portion for determining the presence of a first image with at least a first number of pixels having a density-related value of at least a predetermined value continuously arrayed in a subscanning direction, and with at least a second, greater, number of pixels having the density-related value of at least the predetermined value continuously arrayed in a main scanning direction. It also includes a second determining portion for determining a target temperature at which to maintain a fixing portion based on the presence of the first image, when a determination result indicates the presence of the first image, or based on a density-related value of a second image different from the first image, when the determination result indicates the absence of the first image. The apparatus controls power to the fixing portion to maintain its temperature at the determined target temperature.

An image forming method for an image forming apparatus having a fixing rotator and a pressure rotator opposite the fixing rotator includes transferring white toner and color toner onto a surface of a metallic sheet. The metallic sheet has a thermal conductivity of 0.34 W/m.Math.K or less as measured by hot-wire method. The transferring process forms an unfixed color toner layer layered on an unfixed white toner layer on the metallic sheet. Further, the method includes conveying the metallic sheet, with the surface on which the white toner layer and the color toner layer being transferred facing the fixing rotator, between the fixing rotator heated and the pressure rotator to fix the white toner layer and the color toner layer onto the metallic sheet.

An image forming apparatus, including: determining presence or absence of a first image in which at least a first number of pixels each having a density-related value are continuously arrayed in a subscanning direction, and in which at least a second number of pixels each having the density-related value are continuously arrayed in a main scanning direction, the second number being greater than the first number; determining a target temperature based on the presence of the first image when a determination result indicates the presence of the first image, or determine the target temperature based on a density-related value of a second image that is different from the first image when the determination result indicates the absence of the first image; and controlling power to be supplied to a fixing portion so that a temperature of the fixing portion is maintained at the target temperature.

An image forming apparatus includes an image forming unit, a fixing device, and a control circuit. The control circuit acquires a selection signal indicating which mode is selected from among options. The options include at least two modes, including a first mode in which an image is formed using a non-decolorable first toner, a second mode in which the image is formed using a decolorable second toner, and a third mode in which the image is erased by heating a sheet on which the image is formed by the second toner using the fixing device at a decolorizing temperature. The control circuit sets a different standby temperature in accordance with the mode indicated by the selection signal, and controls a temperature of the fixing device to be the standby temperature, in a standby state before an operation start reception.

An image heating apparatus includes first and second heat generating elements arranged adjacent to each other, and a control portion that controls power supplied to the first and second heat generating elements, and that is capable of individually controlling the first and second heat generating elements, the first and second heat generating elements being respectively controlled so as to maintain a control temperature. When an image exists in a second region on the recording material heated by the second heat generating element, and an image does not exist in a first region on the recording material heated by the first heat generating element, the control portion sets the control temperature of the second heat generating element, when heating the second region, in accordance with a distance between an end section of the image in the second region and a boundary of the first region and the second region.

An image forming system includes an image forming unit, a varnish applying unit, a conveying unit, an irradiation unit, and a controller. The controller controls conveyance of a recording material so that a conveying speed of the recording material in a case that varnish is applied to the recording material with a toner image is formed is slower than a conveying speed of the recording material in a case that varnish is applied to the recording material with no toner image. The controller controls irradiation of the varnish with light so that intensity of the light with which the varnish is irradiated in a case that the varnish is applied to the recording material with the toner image is lower than intensity of the light with which the varnish is irradiated in a case that the varnish is applied to the recording material with no toner image.

An image forming method for an image forming apparatus having a fixing rotator and a pressure rotator opposite the fixing rotator includes transferring white toner and color toner onto a surface of a metallic sheet having a thermal conductivity of 0.34 W/m.Math.K or less as measured by hot-wire method to form an unfixed color toner layer layered on an unfixed white toner layer on the metallic sheet and conveying the metallic sheet, with the surface on which the white toner layer and the color toner layer are transferred facing the fixing rotator, between the fixing rotator heated and the pressure rotator to fix the white toner layer and the color toner layer onto the metallic sheet.

In accordance with an embodiment, an image forming apparatus comprises an image forming section, a fixing section and a controller. The image forming section forms a toner image with at least one selected from a first toner having a first fixing temperature area and a second toner having a second fixing temperature area of which a lower limit fixing temperature is higher than the first toner. The fixing section fixes the toner image on the sheet. The controller controls a standby temperature of the fixing section to a temperature lower than the lower limit fixing temperature of the second fixable temperature area.

An image forming apparatus according to one embodiment includes a transport unit, an image forming unit, a heating member, a first pressurizing member, a second pressurizing member, and a processor. The transport unit is configured to transport a print medium. The image forming unit is configured to form a toner image on the print medium by a first toner. The first pressurizing member is configured to form a fixing nip for fixing with the heating member. The second pressurizing member is configured to form a decolorizing nip for decolorizing with the heating member. The processor is configured to control the heating member to the first temperature, allows the print medium on which the toner image is formed by the first toner to pass through the fixing nip, and allows the print medium on which an image is formed by a second toner, to pass through the decolorizing nip.

An image forming system including an image forming apparatus, a varnish applying apparatus, an input unit, a first image processing unit, and a second image processing unit. The image forming apparatus forms a toner image on a recording material on the basis of image data obtained by subjecting first image data to data change processing. The varnish applying apparatus forms a varnish image on the recording material on the basis of image data obtained by subjecting second image data to the data change processing.