Method for effecting development by applying an electric field of bias

摘要

The present invention includes a method for effecting development by coating an insulative toner on a developer supporting member having its conductive surface in the form of a roller or the like and then contacting the toner layer with a latent-image bearing surface. Furthermore, a cyclic displacement voltage such as AC voltage and pulsating voltage is applied between the development clearance to produce such an electric field of bias that, in at least the latter half of the developing process, is smaller than a threshold for actually separating the toner in such a direction that the deposited toner is separated from the image area, and also smaller than a so-called fog threshold for actually depositing the toner in such a direction that the toner is deposited on a non-image area.