REMOVAL OF ORGANIC MATERIAL FROM XEROGRAPHIC DEVELOPERS
Original Publication Date: 1994-Jun-30
Included in the Prior Art Database: 2004-Apr-07
Xerox Disclosure Journal
Disclosed is a process for the removal of organic material from xerographic developers that are used in electrophotographic printing and copying machines. In two component xerographic dry imaging processes, the xerographic developer comprised of toner and carrier particles degrades in imaging performance with time for a variety of reasons, rendering the developer incapable of properly charging the toner. This phenomena results in poor copy quality and the spent developer must be replaced. Thus, a need exists for an economical and environmentally sound means of regenerating or recycling the spent developer. Reclamation of the spent developer requires, for example, removal of toner particles impacted on the carrier surface, removal of paper fibers from the developer, and removal of tribo controlling organic coatings from the surface of the carrier particles. Use of a combination of industrial laser irradiation steps to strip away the organic material by ablation and volatilization, provides a solvent free, high throughput, for example, in excess of 1,000 pounds per hour, continuous process for recycling or reclamation of spent developer. The laser mediated stripping process for spent developers may be coupled to oxidation and/or powder coating and fusing steps in the remanufacture of finished carriers. Thus, a process for the removal of organic material from xerographic developers comprises: a.) mechanically separating free toner particles from carrier particles, using, for example, a screen or sieve; b.) selectively irradiating the separated carrier particles with a low glancing or incident angle laser beam to remove or "clean" impacted toner material from the surface of the carrier and reusing the "cleaned" carrier; and c.) optionally further irradiating the cleaned carrier particles to remove tribo controlling organic surface coatings from the carrier particles to provide bare or virgin surface carrier particles suitable for recoating.