SU911449A1 - Method of forming electrostatic image on intermediate electrographic carrier - Google Patents

Description

I

The invention relates to electrophotography, specifically to physicotechnological processes for obtaining a latent electrophotographic image.

The classical method of producing an electrophotographic image is known, consisting of charging the electrophotographic layer, exposing the image, developing, transferring the developed image and preparing the layer to the next cycle C i.

However, with frequent repetitions of image formation on the same carrier, the effect of fatigue is observed, which is characterized by the fact that under the cyclic charge-exposure mode, the appearance with each successive cycle decreases the maximum charge potential of the intermediate carrier, decreases the electrical charge.

image contrast, which ultimately leads to a deterioration in the quality of the formation of a latent electrostatic image.

The closest. The proposed method of forming a latent electrostatic image on an intermediate electrophotographic carrier, comprising an amorphous selenium layer, in which electrical fatigue is reduced and the primary charge is charged by ions of the same sign, image exposure, latent electrostatic image,

15, the transfer of the image to the terminal carrier and the final charge of the intermediate carrier to relieve electrical fatigue, with the final charge being carried out by the polarity opposite to the primary charge 23.

Claims (2)

However, the known method does not reduce the effect of fatigue in electro 39 photographic semiconductor carriers with monopolar electrical conductivity and a high concentration of local states that occur, for example, in a layer of a three-selenic mouse. In addition, in the known method, the final charging of a three-settlement mouse with a negative charge after a cycle with a positive charged charge leads to an even stronger decrease in the subsequent positive limiting potentials of charging selenium layers. The purpose of the invention is to improve the quality of forming a latent electrostatic image, including on layers of a three-mouse arsenal. This goal is achieved in that the method of forming an electrostatic image on an intermediate electrophotographic carrier, including primary charging of an intermediate carrier with ions of the same sign, exposure of the image, developing a latent electrostatic image, transferring the image to the terminal carrier and final charging of the intermediate carrier to remove fatigue, during the final charge, the carrier is uniformly illuminated by strongly absorbed radiation, while the charge is od t ions of the same polarity as the initial charging. FIG. 1, 2, and 3, the essence of the physical process of eliminating electrical fatigue and increasing the limiting potential behind rows of a tired electrophotographic layer is explained. Usually, when charging an electrophotographic layer (Efe), charges are deposited on the surface of the layer, and charges of the opposite value (shielding) are induced at the interface between the semiconductor and the metal substrate (Fig. 1). However, there are electro-photographic layers, during charging of which part or all of the shielding charge is formed not in the substrate, but in the bulk of the semiconductor layer (Figure 2). This is especially characteristic of Efe made of semiconductors with monopolar conductivity and high concentration: local states, as it was 4 threesome mouse. During the charging of such EPS, mobile charges under the action of heat and a strong electric field are excited from the smallest states and are removed from the layer, and in the bulk of the layer form The volume charge of the fixed carriers, which partially or completely shields the surface charge. Illumination of the layer with weakly absorbed or white light increases this effect, and the effective thickness of the layer decreases as a result of the redistribution of charges in the layer and the accumulation of screening charge at the surface of the layer ( FIG. 3). This also leads to a significant decrease in the limiting potential of the charge. It should be noted that discharging the layer to zero when illuminated with white light or weakly absorbed light does not eliminate the effect of fatigue, since a compensated charge of both polarities is formed. When recharging, the mobile carriers are partially removed from the layer and the effective thickness is further reduced. The restoration of the potential of a charge is caused only by an intense flow-hole, which is injected from the surface of the layer when it is illuminated with a highly absorbing light, and the presence in the layer of the field created by additional charging. The holes in the bulk of the layer partially recombine with fixed electrons and partially capture not only shallow but also deep levels of adherence. In this way, the density of the negative volume charge is reduced, electrical fatigue is eliminated and the potential of the charge is increased to the initial one. Claim T. The method of forming an electrostatic image on an intermediate electrophotographic carrier, including the primary charging of an intermediate carrier with ions of the same sign, exposing the image, developing an electrostatic latent image, transferring the image to the terminal carrier and terminating the intermediate carrier to remove the electrical fatigue, characterized in that, in order to improve the quality of formation of the latent electrostatic image, during the final charge, the carrier is uniformly illuminated by strongly absorbed radiation, while the charge is produced by ions of the same polarity as the primary charge. 2. The method according to p. 1, about t l and c a yu and also with the fact that as a mate-f 4-H-4-f-f-f-f 4- -H-f The riial of the photosensitive electrophotographic layer of the carrier is used by a three-armed mouse. Sources of information taken into account in the examination 1.Dessauer J.H., Mott G.R., iBogdanoff N. Photographic Ei ineerdng - 6, 1955, No. if, c. 250-268. 2. US patent number, CL. 96-1, 1956. /.- t / uug / yy / / that tU / / t of fig. / H- N- + 4- + H- 4-4-4-4-4-4-4 L ///// G ///// 7 ////// Ф & г.2. 4-4 - е-Ь 4-4-4-4-4-Ч-4- + 4