Abstract: A process is proposed for the double-sided printing and/or coating of a substrate using at least one liquid or dry toner that has at least one polymer. It is provided that at least one toner layer or a first image that has at least one toner layer is transferred onto a first side of the substrate. Then, the toner is heated up to at least its glass transformation temperature, and fixed onto the substrate. In the process, the original glass transformation point of the toner shifts to a higher temperature level as a result of the cross-linking of its polymer chains, and the viscosity is increased. In a second processing step, at least one toner layer or a second image is transferred onto the second side of the substrate and heated up to a temperature that is equal to or greater than its glass transformation temperature.

Abstract: A process and device for fusing toner onto a carrier or a print substrate, in particular a sheet-like print substrate, preferably for a digital printing machine, wherein the toner bearing print substrate is heated by microwaves emanating from at least one microwave emitter in order to melt the toner, and wherein a toner is used that demonstrates a sharp drop-off in the elastic module G′ from its solid to its liquid state upon heating. The ratio of the elastic module G′ of the toner at the reference temperature, calculated from the initial temperature at the start of the glass transition of the toner plus 50° C., to the value of the elastic module G′ at the initial temperature itself is preferably <10−5.

Abstract: A digital printing or copying machine (1) is proposed for the one-sided or double-sided printing onto a substrate (5), using at least one toner. The machine (1) includes at least one fixation device (3) for fixing the toner image on the substrate (5). The fixation device (3) has at least one heating device (13) for melting the toner image, past which the substrate (5) can be taken. The machine (1) is distinguished by a guide device (17) for the free floating movement of the substrate (5) in the effective range of the heating device (13).

Abstract: A process is proposed for the double-sided printing and/or coating of a substrate using at least one liquid or dry toner that has at least one polymer. It is provided that at least one toner layer or a first image that has at least one toner layer is transferred onto a first side of the substrate. Then, the toner is heated up to at least its glass transformation temperature, and fixed onto the substrate. In the process, the original glass transformation point of the toner shifts to a higher temperature level as a result of the cross-linking of its polymer chains, and the viscosity is increased. In a second processing step, at least one toner layer or a second image is transferred onto the second side of the substrate and heated up to a temperature that is equal to or greater than its glass transformation temperature.

Abstract: A digital printer or copier machine (1) is proposed for the single-sided or double-sided printing of a substrate (11), with at least one fixing device (3) for fixing toner onto the substrate (11), whereby the fixing device (3) has at least one heating device for fusing the toner. The machine has, in addition, at least one transport device (17), in order to supply the substrate (11) to the heating device, to guide it past the heating device and/or to further transport it from the heating device, whereby the transport device (17) has at least one suction belt (19) that is provided with a number of through-passage openings (21) and can be impinged with a vacuum. The machine (1) is characterized in that the suction belt (19) is constructed as a mesh.

Abstract: Digital printers or copier machines (1) and processes to be performed using them, for fixing a toner image (5) transferred onto an image-carrier substrate (9), are proposed. One of the processes is characterized in that to fuse the toner particles, at least two electromagnetic radiation pulses are applied in a time-delayed manner onto the same area of the image-carrier substrate (9).

Abstract: A method for fixation of toner on a carrier or printing stock wherein the printing stock with toner is exposed to at least one radiation pulse or radiation flash of electromagnetic radiation and heated for melting of the toner, and a toner having a sharp transition from its solid to liquid state when heated is used. The toner is preferably characterized by the ratio of the value of the elastic modulus G′, at the reference temperature value calculated from the initial temperature at the beginning of the glass transition of the toner plus 50° C., to the value of the elastic modulus G′ at the initial temperature itself, is less than 10−5.

Abstract: A radiation unit for a fixation device for fixation of toner material on a printing stock surface for an electrophotographic printing machine, as well as a method for exposure and fixation of toner material on a printing stock surface. Exposure for fixation of toner material occurs essentially indirectly, i.e., the light emitted by the radiation unit is reflected at least once, so that high uniformity and homogeneity of the radiation, efficient energy utilization and avoidance of adverse changes on the printing stock are achieved. A high-energy density, low housing dimensions and independence of the radiation from the employed printing unit are achieved by the fact that the radiation wavelength lies essentially in the ultraviolet spectral range.

Abstract: A device and process for fixing a toner onto a substrate or a printed material, especially a sheet-shaped printed material, preferably for a digital printer, which is characterized in that the printed material that has the toner is irradiated with microwaves from at least one microwave emitter and is heated to melt the toner and that a toner is used which exhibits a sharp drop of the modulus of elasticity G′ from its solid to its liquid state when it is heated. Preferably, the ratio of the value of the modulus of elasticity G′ of the toner according to the invention at the reference temperature value, calculated from the starting temperature at the beginning of the glass transformation of the toner plus 50° C., to the value of the modulus of elasticity G′ at the starting temperature itself is <10−5.

Abstract: A device and process for fixing a toner onto a substrate or a printed material, especially a sheet-shaped printed material, preferably for a digital printer, which is characterized in that the printed material that has the toner is irradiated with microwaves from at least one microwave emitter, and is heated to melt the toner, and that a toner is used which exhibits a sharp drop of the modulus of elasticity G′ from its solid to its liquid state when it is heated. Preferably, the ratio of the value of the modulus of elasticity G′ of the toner according to the invention at the reference temperature value, calculated from the starting temperature at the beginning of the glass transformation of the toner plus 50° C., to the value of the modulus of elasticity G′ at the starting temperature itself is <10−5.

Abstract: A process or device for fusing toner on a carrier or a printing material, particularly a sheet-type printing material, preferably for a digital printer, wherein the printing material with the toner is irradiated with microwaves from at least one microwave conductor, which is heated to melt the toner and a toner is used which shows a sharp drop of the elastic modulus G′ from its hard state to its liquid state when heated. The ratio of the value of the elastic modulus G′ of the toner is the reference temperature value calculated from the initial temperature at the beginning of the glass transition of the toner plus 50° C. to the value of the elastic modulus G′ at the initial temperature is <10−5.

Abstract: A digital image recording process is proposed. The process provides that a color toner image made of toner layers having different colors is transferred onto an image receiving substrate and then fused and fixed onto the image receiving substrate by impingement with electromagnetic radiation. The process is characterized in that in order to produce the color black, at least one toner layer is used that has similar absorption properties, at least for one wavelength within a predetermined wavelength range for the electromagnetic radiation, as the other toner layers that are used.

Abstract: The invention concerns a machine for application and fixation of curable toner through a substrate and a method for printing and/or coating a substrate, especially paper or cardboard. The method proposes the use of at least one curable toner in which at least one toner layer or at least one image having a toner layer is transferred to the substrate and fixed on it. The method is characterized by the degree of melting of the toner layer being fixed being controlled as a function of the desired luster.

Abstract: The invention relates to a process for coating a substrate with a powder paint composition. The powder paint particles are first charged by friction or induction in the presence of magnetic or nonmagnetic particles, are next transported and are then applied to the substrate or applied to a transfer medium and subsequently transferred to the substrate, by means of an electric field between the substrate respectively the transfer medium and the means of transport whereafter the ponder paint composition is cured or fused to obtain a powder coating.

Abstract: A novel carrier which is stable and effective over long cycle times (6.times.10.sup.6 prints), has an iron oxide coating of the formula (FeO).sub.x.Fe.sub.2 O.sub.3 where x=0.1-1 and is obtained by treating steel cores (or balls) with defined small amounts of sulfuric acid of defined concentration, partial oxidation of the cores thus treated and drying at 60.degree.-150.degree. C. at .ltoreq.100 mbar.

Abstract: Carriers for a two-component dry developer are based on a ferrite or iron-containing core which carries a metal oxide layer consisting of reaction products deposited in the gas phase.The carriers according to the invention have abrasion-resistant metal oxide layers which permit electrostatic charging in both directions. By adjusting the thickness of the metal oxide layer, the electrical conductivity can be altered.

Abstract: Colored single-component toners essentially consist of a magnetic pigment, a binder based on an organic polymer and/or a wax, a dye or colored pigment homogeneously distributed in the binder, and other assistants, the magnetic pigment being iron powder which has a spherical or elliptical shape.