Patent ID: 6821700
Filing Date: 2004-11-23
Classification: G03G

Abstract:
Apparatus for non-interactive, dry powder development of electrostatic images comprising:an image bearing member bearing an electrostatic image; a housing containing two component developer comprising toner and permanently magnetized thickly coated carrier beads, the beads having a carrier bead core radius r, a coated carrier bead radius a, and a magnetization Mb, and wherein the ratio K of the radius r to the radius a is a quantity less than about Â¾; a developer transporting member, disposed in said housing, having a predefined thickness (t) for transporting a developer layer of said two component developer, said layer spaced close to and out of contact with said image bearing member; and a multipole magnet member disposed in close proximity behind said transporting member, and moving relative to it so as to sweep poles across its surface, said magnet member having a predefined periodic magnetization of spatial frequency (k) and a predefined peak magnetization (M0).