Patent ID: 6099110
Filing Date: 2000-08-08
Classification: B41J

Abstract:
An image forming apparatus comprising:supplying means having a holder for holding a developer for developing at least one color;a counter electrode disposed so as to face the holder;a control electrode disposed between the holder and the counter electrode, including:an insulated substrate provided with a plurality of gates through which the developer passes,one or more groups of electrodes disposed around the plurality of gates of the insulated substrate, anda shielded electrode having openings corresponding to the plurality of gates of the insulated substrate, the shielded electrode being disposed on the insulated substrate so that a part of the groups of electrodes is exposed directly or electrically to the holder through the openings;controlling means having a control circuit, for applying at least a predetermined electric potential according to image data, to respective electrodes of the control electrodes;wherein the image forming apparatus forms an image on a surface of a recording medium fed to between the control electrode and the counter electrode while the passage of the developer through the gates is controlled by applying a predetermined electric potential to the groups of electrodes by the controlling means;wherein, just before passing through the gates, the developer is controlled so that a change in the status of the developer is obtained such that a sticking force between the developer and the holder or among particles thereof is weakened, or that the developer is transformed into cloud-like particles; andwherein the status of the developer is controlled by a pulse electric potential generated by the control circuit.