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:
Oct. 29, 1991
Filed:
Jul. 02, 1990
Delmer G Parker, Rochester, NY (US);
William M Allen, Webster, NY (US);
Jerome E May, Rochester, NY (US);
Xerox Corporation, Stamford, CT (US);
Abstract
A hybrid development system for developing composite tri-level xerographic latent images in which conductive magnetic brush (CMB) development system is employed at the first development station and insulative magnetic brush (IMB) development system is used at the second station. In order to preclude spurious fringe field development by the IMB development system at the second development station the conductivity of the IMB developer is in the order of 10.sup.-13 to 10.sup.-15 ohm-cm. Additionally, a scorotron corona charging device located between the two development housings may be used to charge the image developed at the first station to the same potential as the background (white level) thereby eliminating spurious fringe field development by the IMB developer with a conductivity less than 10.sup.-13 ohm-cm at the second development station.