METHOD AND APPARATUS FOR PRODUCING IMPROVED ELECTROGRAPHIC DEVELOPER

摘要

Abstract of the DisclosureA method for preconditioning an electrographicdeveloper comprising an unconsolidated mass of discreteparticles of a carrier and of a toner which carries acharge control agent of negative or positive polarity,said method comprising repeatedly passing a flowing streamof such developer through an electrostatic field between apositive or negative electrode and a grounded electrode ofopposite polarity, and attracting part of said tonerparticles to the electrode of sign opposite the sign ofsaid charge control agent. The grounded electrode hasan inclined surface and the stream of developer slidesdown such surface under the other electrode, which isparallel to the grounded electrode. The apparatus in-cludes mixing mechanism for mixing the developer, andconveying mechanism for carrying mixed developer from thebottom of the inclined grounded electrode back to the topfor repeated passage through the electrostatic field.