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:
Feb. 28, 1984
Filed:
Jul. 15, 1982
Jerry J Abbott, Longmont, CO (US);
Stephen C Crossan, Longmont, CO (US);
Sterritt R Fuller, Jr, Boulder, CO (US);
Paul D Jachimiak, Lafayette, CO (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A developer material comprising toner particles and coated carrier beads for use in developing images in an electrostatographic device is disclosed. The toner particles are initially classified according to a size distribution wherein less than 15% by weight are greater than 16 microns, between 7 and 15% by weight are less than 5 microns, the remainder being from 5 to 16 microns; and wherein the median particle size by weight is from 8 to 12 microns. The carrier beads have a core with a coating thereon. The coating is a mixed resin system comprising 5 to 55% by weight polytetrafluoroethylene, 5 to 55% by weight fluorinated polyethylene-propylene, and 40% to 80% by weight of a poly(amide-imide) resin which is stable up to at least 600.degree. F., triboelectrically negative (with respect to the herein described toner), nonspalling, essentially nonfriable and dispersible with the other resin components. Also, preferably the coating includes a pigment, such as TiO.sub.2, dispersed in the resin system. More specific ranges of size classification of the toner particles and preferred ranges of resin components are also disclosed.