Patents Examined by Sliriue P. Beck
  • Patent number: 5705221
    Abstract: A method of modifying the triboelectric charging propensity electrostatographic developer carrier particles, comprising the steps of:(A) providing a carrier particles that is uncoated or polymer coated;(B) mixing the carrier particles with either (i) an aqueous basic solution or (ii) an aqueous solution containing from 0.1 to 5.0 weight percent of a soluble acidic metal salt, based on the weight of the carrier particles to form a mixture; and(C) contacting the mixture with the solution, (i) or (ii), not used in step (B) thereby causing a precipitate of an insoluble salt to deposit on the carrier particles wherein the insoluble salt is(a) strontium carbonate;(b) insoluble metal hydroxides;(c) insoluble metal hydrated oxides; or(d) a mixture of two or more of (a), (b) and (c);provided that when a soluble strontium metal acid salt is used in step (B) (ii) and the carrier coating is other than a polyfluorocarbon, a reagent that provides a source of carbonate ions is also used in step (B).
    Type: Grant
    Filed: April 10, 1996
    Date of Patent: January 6, 1998
    Assignee: Eastman Kodak Company
    Inventor: William Edward Yoerger