Abstract: A method of making a conductive fiber in which the conductive fiber is formed from a mixture including at least one fiber forming material and conductive magnetic materials, and the conductive magnetic materials are migrated toward the periphery of the fiber by application of a magnetic field to the fiber. The conductive fibers having the conductive magnetic materials located at the periphery of the fiber are preferably incorporated into an electrostatic cleaning device for use in an electrostatographic printing device.

Abstract: Magnetic developer compositions contain ferrous carbon. The ferrous carbon is a fibrous, particulate carbonaceous material comprising carbon fibers and a ferrous group metal component, where the ferrous group metal component is dispersed throughout the carbon fibers as nodules that are initmately associated with and at least partially bonded to the carbon fibers. The ferrous carbons can be used in monocomponent developers, and also in the toner and carrier used for dual component developers.

Abstract: Electrostatographic carrier particles having been classified as to have a surface roughness value of less than about 2.0 to provide improved developer life. Developer mixtures and imaging processes employing the described carrier particles are also disclosed.

Abstract: An electrostatographic imaging process comprising the steps of providing an electrostatoraphic imaging member having a recording surface, forming an electrostatic latent image on said recording surface, and contacting said electrostatic latent image with a developer mixture comprising finely divided toner particles electrostatically clinging to the surface of classified high surface area carrier materials having a specific surface area of at least about 150 cm.sup.2 /gram, a particle size volume distribution geometric standard deviation of less than about 1.3, and a particle size distribution wherein the carrier particles have an average particle diameter of less than about 100 microns, whereby at least a portion of said finely divided toner particles are attracted to and deposited on said recording surface in conformance with said electrostatic latent image.

Abstract: Classified high surface area carrier materials having a specific surface area of at least about 150 cm.sup.2 /gram, a particle size volume distribution geometric standard deviation of less than about 1.3, and a particle size distribution wherein the carrier particles have an average particle diameter of less than about 100 microns. The carrier materials are mixed with finely-divided toner materials to form electrostatographic developer mixtures.

Abstract: Classified toner materials having a particle size number distribution with a fine index ratio of less than about 2.50, a particle size volume distribution with a coarse index ratio less than about 1.50, and a particle size distribution wherein less than about 30.0 percent by number of the toner particles have an average particle size diameter of less than about 5 microns, about 25 percnt of the particles have a diameter between about 8 microns and about 12 microns and less than about 5 percent by number of the toner particles have an average particle diameter greater than about 20 microns. The toner materials may be mixed with carrier materials to form electrostatographic developer mixtures.

Abstract: A process for preparing humidity-insensitive electrostatographic ferrite carrier materials comprising dry-blending ferrite-forming metal oxides, calcining the blended oxides to provide them with a saturation magnetic moment of about 6 to 30 electromagnetic units per gram, milling the calcined oxides in a slurry to reduce their particle size to about 0.8 to 1.6 microns while adding manganese oxide, copper oxide, and a sodium-free deflocculant to the slurry, pumping the milled slurry to holding/feeding tanks and adding a binder material to the slurry, spray-drying the slurry to form substantially spherical beads, screening the spray-dried beads, firing the screened beads in an ambient atmosphere at a temperature of up to about 2500.degree. F. for up to about 8 hours, deagglomerating the fired beads, and screening the beads to obtain ferrite carrier particles having controlled surface species and physical properties.

Abstract: Humidity insensitive, uncoated electrostatographic carrier materials comprising substantially stoichiometric ferrite compositions using various divalent metal oxides and/or one monovalent metal oxide, singly and in combination, which are within about .+-. 3 mol percent deviation from stoichiometry in divalent metal content. The carrier materials may be mixed with toner materials to form developer mixtures and employed to develop electrostatic latent images.

Abstract: Classified high surface area carrier materials having a specific surface area of at least about 150 cm.sup.2 /gram, a particle size volume distribution geometric standard deviation of less than about 1.3, and a particle size distribution wherein the carrier particles have an average particle diameter of less than about 100 microns. The carrier materials are mixed with finely-divided toner materials to form electrostatographic developer mixtures.

Abstract: Humidity-insensitive electrostatographic ferrite carrier materials having an average particle diameter from between about 30 to about 1,000 microns prepared by blending an essentially stoichiometric mixture of ferrite forming metal oxides, calcining the blended oxides to provide the blended oxides with a saturation magnetic moment of between about 6 to about 30 electromagnetic units per gram, milling the calcined oxides in a slurry to reduce their particle size, adding manganese oxide, copper oxide, sodium-free deflocculant, and water to the slurry to provide a slurry having about 80.

Abstract: An electrostatographic developer mixture comprising classified toner materials electrostatically clinging to the surface of classified high surface area carrier materials said classified toner materials having a particle size number distribution with a fine index ratio of less than about 2.50, a particle size volume distribution with a coarse index ratio less than about 1.50, and a particle size distribution wherein less than about 30.0 percent by number of the toner particles have an average particle size diameter of less than about 5 microns, about 25% of the particles have diameter between about 8 microns and about 12 microns, and less than about 5% by number of the toner particles have an average particle diameter greater than about 20 microns, said classified high surface area carrier materials having a specific surface area of at least about 150 cm.sup.2 /gram.

Abstract: An electrostatographic imaging process comprising the steps of providing an electrostatographic imaging member having a recording surface, forming an electrostatic latent image on said recording surface, and contacting said electrostatic latent image with a developer mixture comprising classified toner materials electrostatically clinging to the surface of classified high surface area carrier materials, said classified toner materials having a particle size number distribution with a fine index ratio of less than about 2.50, a particle size volume distribution with a coarse index ratio less than about 1.50, and a particle size distribution wherein less than about 30.