The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 25, 1992
Filed:
Feb. 23, 1990
Khe C Nguyen, Pittsford, NY (US);
William T Gruenbaum, Rochester, NY (US);
Eastman Kodak Company, Rochester, NJ (US);
Abstract
An electrophotographic coating composition comprising finely-divided photoconductive perylene pigment dispersed in a solvent solution of polymeric binder is prepared by the steps of (1) milling a perylene pigment with milling media comprising inorganic salt and non-conducting particles under shear conditions in the substantial absence of the solvent to provide pigment having a particle size up to 0.2 micrometer, (2) continuing the milling at higher shear at a temperature up to about 50.degree. C., to achieve a perceptible color change of the pigment particles, (3) rapidly reducing the temperature of the milled pigment by at least 10.degree. C., (4) separating the milled pigment from the media and (5) mixing the milled pigment with the solvent solution of polymeric binder to form the coating composition. A very high degree of dispersion of photoconductive perylene pigment in solvent solution of polymeric binder is achieved by this method.