Abstract: Hot offset of black toner is reduced or eliminated in a color electrophotographic imaging device, such as a laser printer, by applying a minimal layer of non-black toner in addition to the black toner on a print media. The non-black toner, such as cyan, magenta or yellow toner, acts as a release agent for reducing or eliminating hot offset of the black toner during fusing of the toner to the media. The non-black toner is applied as a thin layer just sufficient to reduce hot offset of the black toner and such that an appearance of a resultant image formed retains a visual perception of being a black toner only image. In an alternate embodiment, the thin layer of non-black toner is applied in response to coated media being processed, such as overhead transparencies, that are more susceptible to hot offset.

Abstract: In a fusing device having first to third rollers, the first and second rollers are forcibly driven so that a peripheral speed of the third roller is higher than of the first roller. Further, a movable guide is set so as to change the number of nip portions through which a recording medium passes.

Abstract: An electrostatographic printer is provided in which a web of receiving material (12) is fed along a web path, at least one toner image is formed on at least a first face of the receiving material (12) as it is fed along the web path and the toner image is fixed onto the receiving material (12). A finishing element (66, 67) positioned downstream of the fixing station (16) contacts the first face of the receiving material (12) while the finishing element is at a temperature above the glass transition temperature T.sub.g of the toner to modify the finish of the toner image.

Abstract: An image forming apparatus includes a first developing device, accommodating a first kind of toner without an offset preventing agent, a second developing device accommodating a second kind of toner containing an offset preventing agent, and a roller fixing device having a supply portion for supplying an offset preventing agent. The image forming apparatus changes the amount of the offset preventing agent to be supplied to the fixing roller between the case of fixing a copy image formed with the first kind of toner and the case of fixing a copy image formed with the second kind of toner.

Abstract: There is provided a method and device for automatically selecting a gloss finish for a print from an electrophotographic printing machine. The image characteristics and color content are determined and if the characteristics and content exceed a predetermined level, an auto gloss signal is generated by the machine controller. In one instance, a glossy substrate is selected upon which to print the image. In a second instance the fuser is adjusted so as to produce a glossy image output on the substrate. There is also a user selectable mode in which either all prints can be produced on a gloss substrate or on a matte substrate depending on the desired state.

Abstract: An image forming apparatus includes a first printing unit which forms a first image on a sheet with a first printing material and fixes the first image thereon by heat application; and a second printing unit which forms a second image with a second printing material on the sheet having the first image formed by the first printing unit, and fixes the second image thereon by heat application; the second printing material has a lower melting temperature than the first printing material and the second printing unit applies a lower temperature heat for fixation of the second image than the first printing unit.

Abstract: To provide a hot roller type thermal fixation device, incorporated in an electrostatic recording apparatus, particularly suitable for the thermal fixation of a multicolor toner image, said apparatus comprising a plurality of electrostatic recording units arranged in series with each other, wherein the surface smoothness of a fixed toner image is maintained at a favorable level for a long period by providing an anti-abrasive treatment onto an elastomeric covering of the heating roller. An elastomeric covering (32b) is applied on the surface of a heating roller (32) of a hot roller type thermal fixation device (22), and an anti-abrasive covering (32c) is further applied on the elastomeric covering.