Abstract: In a toner-fixing heater device, a heater strip in a meandering pattern and a pair of heater electrodes are formed on an insulator film which is in turn fixed to a cylindrical roller body. Each heater electrode which slidably contacts a brush electrode has a leading and trailing edges formed inclinedly at an inclination angle .theta., e.g., 50.degree.. The axial width Wd of the heater electrode 14, the circumferential width Wg of a spacing between the leading and the trailing edges, and the circumferential width Wb of the brush electrode are determined to satisfy (Wd/tan .theta.+Wd).gtoreq.Wg. This arrangement assures a continuous sliding contact between the heater electrode and the brush electrode.

Abstract: A sheet of paper, plastic or the like on which an image has been formed using a toner that is photochemically decolorizable by absorption of near infrared rays is illuminated with near infrared rays under the state wherein the image is heated to a temperature equal to or higher than the glass-transition temperature of a binding resin of the toner. The color of the toner can thereby be easily and rapidly eliminated. This enables the reuse of the sheet to be realized easily and at a low cost.

Abstract: A sheet of paper, plastic or the like on which an image has been formed using a toner that is photochemically decolorizable by absorption of near infrared rays is illuminated with near infrared rays under the state wherein the image is heated to a temperature equal to or higher than the glass-transition temperature of a binding resin of the toner. The color of the toner can thereby be easily and rapidly eliminated. This enables the reuse of the sheet to be realized easily and at a low cost.

Abstract: An electrophotographic copying machine includes a photosensitive drum on which an electrostatic latent image is formed, a developing apparatus for developing the electrostatic latent image into a toner image, a transferring apparatus for transferring the toner image to a copy paper supplied from a paper supplying portion, a fixing apparatus for heating the copy paper having the toner image transferred thereto to fix the toner image, and a paper ejecting roller for ejecting the copy paper having the toner image fixed thereto to the exterior of the machine body. The copying machine elements are arranged so that the copy paper transporting path from the paper supplying portion to the paper ejecting portion is divided into two assembly units, the assembly units which can be removed from respective predetermined attached positions toward the exterior of the copying machine body in a direction opposite from each other and parallel to the transporting direction of the copy paper.