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. 26, 1986
Filed:
May. 02, 1985
William M Schwarz, Webster, NY (US);
John M Pochan, Racine, WI (US);
Xerox Corporation, Stamford, CT (US);
Abstract
An electrostatographic method and apparatus for developing an electrostatic latent image on an imaging surface, comprises a charging doner member which is preferably a rotatably mounted roll closely spaced from the imaging surface at one portion and having a housing means to be filled with toner positioned adjacent the doner member at another portion together with a web screen located in the housing and adapted to contact the donor member on the portion of its surface opposite the imaging member; the donor member having a surface comprising an active polymer having a basic amine moiety whereby when the donor roll is rotated the rubbing contact between the toner, the screen means and the donor member produces negatively charged toner particles. In a preferred embodiment the active polymer having a basic amine moiety is selected from poly(2-vinylpyridine), poly(4-vinylpyridine), polyvinylpyrolidone, poly (dimethyl aminoethyl methacrylate) and the toner includes a minor amount of fumed silica additive.