Lexmark International, Inc.

George P Marshall

John Melvin Olson

Bryan Patrick Livengood

Brian William Baird

John Joseph Earley

Rick Owen Jones

James Craig Minor

Michael G Miller

Donald Wayne Stafford

Ronald Lloyd Roe

Trent Duane Peter

Vincent Wen-Hwa Ting

Danielle Renee Ashley

Curt J Claflin

Minerva Piffarerio

James Robert Combes

John Y Kim

Lale Gokbudak Lovell

David Brian Bilbrey

Walter Mychajlowskij

Ronald James Whildin

The present disclosure relates to a magenta toner formulation that may be used in a toner printer cartridge for an electrophotographic printer. The magenta toner may include polymer resin binder containing three polymer resins with different number average molecular weight values. The concentration of such polymer resins may be selected to provide a desired temperature versus viscosity behavior for the magenta toner that may be configured to conform to the viscosity versus temperature provide for yellow, cyan and black toner.

Magenta toner with binder resin of selected molecular weight composition

The present invention relates to toner compositions containing extra particulate additives. The additives may include a mixture of silica particles having differing BET surface areas and may include an acicular inorganic oxide. The control of such additives may be relied upon to control toner performance with respect to functional performance considerations such as filming and/or overall print quality.

Toner formulations containing extra particulate additives

Toner is rounded by vigorously mixing less than about 5 percent by weight of particulate silica to the total weight of a starting toner in a closed, recirculating air system. The starting toner contains at least about 4.5 percent by weight of the starting toner of a wax and additionally contains at least 5 percent by weight of the starting toner of a softening agent. The temperature during the mixing is no more than 13 degrees C. above the onset of the glass transition temperature of the starting toner. The final toner comprises rounded starting toner having particulate silica embedded during the mixing process.

Closed air circulation toner rounding

The present invention is a random copolymer and its use to compatibilize the components of mixtures of immiscible polymeric materials used in the preparation of toner formulations.

Random copolymers used as compatibilizers in toner compositions

A toner composition comprising a primary resin and at least one additional polymeric component is improved by reactive compatibilization of the additional polymeric component and the resin. For example, effective amounts of a functional secondary resin and a functional silicone oil having functionality reactive therewith are included and mixed by extrusion so as to reduce or eliminate speckling in printing with the toner and the improve toner powder flow.

Reactive compatibilization of polymeric components such as siloxane polymers with toner resins

A toner composition comprising a primary resin and at least one additional polymeric component is improved by reactive compatibilization of the additional polymeric component and the resin. For example, effective amounts of a functional secondary resin and a functional silicone oil having functionality reactive therewith are included and mixed by extrusion so as to reduce or eliminate speckling in printing with the toner and to improve toner powder flow.

A high speed toner comprising a body of hybrid resin which is about 92 percent by weight polyester and 8 percent by weight polystyrene. Blended in the resin is a charge control agent, a pigment, and about 10 percent by weight of the toner of fumed aluminum oxide. Where the pigments are color-subtractive the charge control agent is a copolymer of styrene and 2-acrylamido-2-methylpropane sulfonic acid. The toner is mixed with a carrier of ferrite particles having a thick silicone coating to remain through the long life of the toner.

Dry xerographic toner and developer

Rubber charge roller cores are coated with styrene acrylic powder. Excess powder is removed, and the rollers are used in normal operation without the usual permanent outer layer. The more complex and costly outer layer of nylon is eliminated. Dust resulting from normal operation replaces the original powder coating.

Powder coated charge roller

A toner for a two component developer used in a high speed computer output printer has about 20 parts gelled styrene/acrylic resin, 40 parts acrylate resin, about 13 parts hydrogenated wood rosin ester with pentaerythritol, and about 18 parts rosin ester of pentaerythritol, as well as carbon black and a charge control agent. Exceptional improvement is noted in carrier deterioration, fuser roller life and photoconductor filming.

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Boulder, CO, United States of America

George P Marshall