Abstract: A process for the preparation of carrier particles which comprises mixing a carrier core with a first polymer; adding to the aforementioned mixture a second polymer not in close proximity in the triboelectric series to the first polymer; and heating the components for a period of time until the first and second polymer fuse to the core.

Abstract: A carrier composition comprised of a core with a coating thereover comprised of a mixture of first and second polymers that are not in close proximity thereto in the triboelectric series, which mixture contains a charge enhancing additive.

Abstract: Disclosed is a process for forming two-color images which comprises charging an imaging member, creating on the member a latent image comprising areas of high, medium, and low potential, developing the low areas of potential with a developer comprising a specific colored toner and a specific carrier as described herein, subsequently developing the high areas of potential with a developer comprising a specific black toner and a specific carrier as described herein, transferring the developed two-color image to a substrate, and permanently affixing the image to the substrate.

Abstract: A process for maintaining the triboelectric stability of an electrophotographic developer composition, comprising:a. providing a first developer composition comprising first toner particles and virgin carrier particles;b. determining the tribo product of said first developer composition;c. providing an aged developer composition by subjecting said first developer composition to at least 5,000 electrophotographic imaging cycles, wherein the tribo product of said aged developer composition is from about 10 to about 200%.multidot..mu.C/g;d. determining the tribo product of said aged developer composition;e. providing a second developer composition comprising second toner particles and said virgin carrier particles;f. incorporating said second developer composition into an electrophotographic imaging device; andg.

Abstract: A process for the preparation of developer compositions which comprises (1) providing carrier particles consisting of a core with a coating thereover; (2) introducing the carrier particles into a blending apparatus; (3) adding to the blending apparatus fine toner particles with a diameter of from about 2 microns to about 10 microns, said particles being comprised of toner resin particles, pigment particles, and a charge enhancing additive; (4) affecting blending for a period of time sufficient to enable the classified toner particles to alter the tribogenerating ability of the surface of the carrier particles and become embedded therein; (5) subsequently adding to the resulting blended mixture toner particles of a diameter of from about 2 to about 18 microns, and comprised of toner resin particles, pigment particles, and a charge enhancing additive; and (6) blending for a period of form about 1 minute to about 5 minutes.