Abstract: A method of producing a custom color particulate toner for use in a two-component developer by mixing two or more component color toners. The component color toners are each surface treated with a blend of two or more types of silica particles, which differ in the functional groups appended to them. The silica blend for each component color toner is chosen so that, when the component color toners are mixed together to form the custom color mixture, they will all tribocharge to the same charge-to-mass ratio when mixed with a carrier to form a developer.

Abstract: Development systems and methods for developing using chemically prepared toners are disclosed. The present invention further discloses developers used in development systems. The use of chemically prepared toners with hard magnetic carrier particles with a non-magnetic, cylindrical shell for transporting developers provides excellent benefits with respect to image quality by reducing granularity and by providing a typically constant, stable developer life as shown by the consistent level of charge to mass over time during operation.

Abstract: Development systems and methods for developing using chemically prepared toners are disclosed. The present invention further discloses developers used in development systems. The use of chemically prepared toners with hard magnetic carrier particles with a non-magnetic, cylindrical shell for transporting developers provides excellent benefits with respect to image quality by reducing granularity and by providing a typically constant, stable developer life as shown by the consistent level of charge to mass over time during operation.

Abstract: Methods for development of an electrostatic image are disclosed that utilize developer compositions with hard magnetic carrier compositions which can provide improved development efficiencies and reduced amounts of image carrier pick-up. The methods utilize hard magnetic carrier particles that are modified to have specific levels of resistivity, such as, for example, of from about 1×105 ohm-cm to about 1×1010 ohm-cm, and a carrier charge-to-mass of greater than about 1.0 &mgr;C/g, which carriers can provide greater development speeds without unacceptable levels of image carrier pick-up. In embodiments, the hard magnetic materials are doped, i.e., bulk substituted, with multi-valent metals to adjust resistivity, while in other embodiments, the hard magnetic materials are coated with at least one multi-valent metal oxide.

Abstract: Methods for development of an electrostatic image are disclosed that utilize developer compositions with hard magnetic carrier compositions which can provide improved development efficiencies and reduced amounts of image carrier pick-up. The methods utilize hard magnetic carrier particles that are modified to have specific levels of resistivity, such as, for example, of from about 1×105 ohm-cm to about 1×1010 ohm-cm, and a carrier charge-to-mass of greater than about 1.0 &mgr;C/g, which carriers can provide greater development speeds without unacceptable levels of image carrier pick-up. In embodiments, the hard magnetic materials are doped, i.e., bulk substituted, with multi-valent metals to adjust resistivity, while in other embodiments, the hard magnetic materials are coated with at least one multi-valent metal oxide.

Abstract: Conductive hard magnetic carrier particles are disclosed which are useful for development of electrostatic latent images. The carrier particles comprise a core of a hard magnetic material, preferably a hard magnetic ferrite such as strontium ferrite, which has a metal oxide composition disposed on the outer surface of the core. The metal oxide composition comprises a layer of an oxide of at least one metal, and in some embodiments, the metal oxide composition may be represented by the formula MOn/2 where M is at least one multi-valent metal represented by Mn+ where n is an integer of at least 4. Also disclosed are carrier particles having the foregoing structure wherein the outer surface of the core further defines a transition zone which extends into the core of hard magnetic ferrite, wherein the ferrite crystal structure within the transition zone is doped with multi-valent metal ions of the formula Mn+, where n is an integer of at least 4.

Abstract: The present invention is an imaged photographic element having a protective overcoat thereon. The protective overcoat is formed by providing a photographic element having at least one silver halide light-sensitive emulsion layer; and applying an aqueous coating comprising polymer particles having an average size of 0.1 to 50 microns at a weight percent of 5 to 50 percent, a soft polymer latex binder at a weight percent of 1 to 3 percent, over the at least one silver halide light-sensitive emulsion layer. The silver halide light sensitive emulsion layer is developed to provide an imaged photographic element. The hydrophobic polymer particles is fused to form a protective overcoat.

Abstract: An improved method and apparatus for robust transfer of toner images using toner particles having a volume average diameter between about 2 .mu.m and about 9 .mu.m is described. Surprisingly good electrostatic transfer is obtained when the surface charge density of the toner is between 3.0.times.10.sup.-9 coul/cm.sup.2 and 6.5.times.10.sup.-9 coul/cm.sup.2 and when this toner is used in conjunction with a compliant transfer intermediate.

Abstract: A clear protective overcoat is provided to an image formed in a silver halide photographic element. The overcoat is formed by electrostatically applying a uniform distribution of clear toner to an imaged photographic element and then fusing the toner to form an overcoat. The toner can be applied only in a limited area of the element.

Abstract: Disclosed is an electrographic recording receiver for use in a process where styli in a writing head deposit electric charges on an electrographic receiver. The receiver comprises a substrate having a conductive layer on an insulating support, a dielectric layer having an image area on the conductive layer, conductive particles embedded in the image area of the dielectric layer in contact with the conductive layer and extending or protruding through the surface of the dielectric layer to provide an electrical path between a ground and the conductive layer through the conductive particles, and insulating particles embedded in and extending through the surface of the image area of the dielectric layer to a distance greater than the conductive particles to provide a substantially uniform distance between the styli and the dielectric layer. Also disclosed is a method of making such a receiver and a method of forming an electrostatic image on such a receiver.

Abstract: The invention provides new crosslinked vinyl polymer particles, new coating compositions containing such particles, new liquid electrographic developers containing such particles, new electrographic elements containing one or more layers comprising such particles, and new electrographic records containing toner images and/or layers comprising such particles.The polymeric particles of the invention are characterized in that each particle has an average diameter less than one micrometer and comprises a crosslinked vinyl addition copolymer obtainable by aqueous emulsion polymerization of a mixture of monomers wherein:1.5-15 percent by weight of the mixture of monomers comprises polyfunctional vinyl addition-polymerizable monomers in order to form crosslinking structural units in the copolymer;85-98.5 percent by weight of the mixture of monomers comprises monofunctional vinyl addition-polymerizable monomers selected such that:A. 0-98.