| 摘要 |
PURPOSE:To prevent carrier particles from attaching to an image bearing member and to process good development with finely pulverized toner and such a carrier by bringing a binary developer layer into contact only with the image parts of an image bearing member at the time of not applying oscillation voltage. CONSTITUTION:When oscillation voltage is not applied, and a space between the surface of a developer layer formed with a magnetic brush and an image bearing member is adjusted to 10-100mum, the developer layer is brought into contact with the image parts of the image bearing member by the electrostatic charge of a latent image formed on the member, and not into contact with the nonimage part. Accordingly, an amt. of the carrier to be transferred is decreased as compared with the case of contacting with all the surface of the member, finely pulverized carrier particles do not attach to the member, and good development is processed by oscillating the binary developer composed of finely pulverized carrier and such a toner by applying oscillation voltage without agglomeration of the fine toner, etc., thus permitting a sharp image high in reproduction fidelity to be formed without deteriorating image quality. |
