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IP.com Disclosure Number: IPCOM000023434D
Original Publication Date: 1977-Oct-31
Included in the Prior Art Database: 2004-Mar-30

Publishing Venue

Xerox Disclosure Journal


To improve the quality of copies made on electrostatic repro-duction machines, a post exposure predevelopment corona gener-ating device is used to treat an electrostatic latent image on a photoreceptor. The device deposits a treating charge onto the latent image of the same polarity as the latent image, the treating charge being of a magnitude sufficient to lower the charge contrast between the background of the latent image and undesirable low density image areas, but not sufficient to detrimontally affect other areas of the latent image. The treating charge may be varied upwardly or downwardly to obtain the desired result, but as it is varied, an electrical bias applied to a developer is simultaneously varied in the same direction so that the magnitude of the bias is always a sub-stantially constant amount above the magnitide of the charge on the background of the latent image.