There are mainly two different types of color formers used in electrostatic subphotography, namely dry toners and liquid color formers. Dry toner can be divided into two types: single-component and double-component dry toner. Two-component dry toner is composed of toner particles and carrier particles. Two-component dry toner is better than single-component toner. The use of component dry toner is more common. In a two-component dry-type toner printing system, the inked portion of the printed image is transferred to the image carrier through carrier particles. Xeikon color digital printing machine is a typical representative of electrophotographic digital printing technology using dry toner. The Xeikon system will be introduced as an example below.

indigital printing machinelaser exposure unit performs image formation on the photoconductor drum, and then develops the image formation section. The density of toner absorbed at each point on the image is controlled by the change in laser exposure intensity. The toner particles are transferred to the substrate and adsorbed on the surface of the substrate. The toner particles are cured by heat and pressure, which strengthens the adhesion of the toner on the paper and improves the printing quality.

Each printing unit generates a monochrome image on one side of the paper according to the same process. As the imaging drum rotates, complete the image and text information transfer on the surface of the imaging drum through the following 6 steps:

(1)Organic photoconductor drum charging;
(2)e electrostatic latent is formed by exposure on the surface of the drum at a resolution of 600dpi through a 4-digit LED array;

(3)The toner particles are transferred to the image area and developed under the action of electrostatic force;

(4)The developed toner particles are in contact with the substrate and transferred to the surface of the substrate under the action of the transfer electrode;
(5)The charge carried by the toner is removed by the cleaning electrode. At this time, there is only one layer of toner on one side of the substrate, which is ready for the next printing unit. In double-sided printing, the other side is then printed;

(6)After the image transfer, in order to prepare for the next printing, remove the remaining toner particles on the imaging drum; when the substrate passes through each printing unit in turn, this process repeats 8 to 10 times according to the number of printing colors to complete the color double-sided print.