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:
Sep. 13, 1988
Filed:
Feb. 26, 1987
Xerox Corporation, Stamford, CT (US);
Abstract
A process is described for preparing vanadyl phthalocyanine for electrophotographic devices comprising reacting vanadium pentoxide and phthalonitile to form vanadyl phthalocyanine pigment and other reaction products, separating crude vanadyl phthalocyanine pigment from the other reaction products, washing the crude vanadyl phthalocyanine pigment, drying the crude vanadyl phthalocyanine pigment, mixing the crude vanadyl phthalocyanine pigment with a solution of between about 60 percent and about 80 percent by weight of H.sub.2 SO.sub.4 to form a H.sub.2 SO.sub.4 -vanadyl phthalocyanine pigment mixture, diluting the H.sub.2 SO.sub.4 -vanadyl phthalocyanine pigment mixture with deionized water to form a diluted mixture, separating the vanadyl phthalocyanine pigment, washing the isolated vanadyl phthalocyanine pigment particles, drying the vanadyl phthalocyanine particles to form the dried, partially purified vanadyl phthalocyanine pigment, dissolving the dried, partially purified vanadyl phthalocyanine pigment in concentrated H.sub.2 SO.sub.4 to form a solution of vanadyl phthalocyanine in concentrated H.sub.2 SO.sub.4, adding the solution of vanadyl phthalocyanine in concentrated H.sub.2 SO.sub.4 to water to precipitate the vanadyl phthalocyanine as vanadyl phthalocyanine pigment particles, separating the precipitated vanadyl phthalocyanine pigment particles from the H.sub.2 SO.sub.4 and water, washing the isolated vanadyl phthalocyanine pigment particles, and drying the vanadyl phthalocyanine pigment particles to form purified vanadyl phthalocyanine pigment.