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. 17, 1996
Filed:
May. 30, 1995
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A single pass EP color printer includes a photoreceptor web having multiple layers and including a charge transport layer and a charge generation layer. Four exposure devices (e.g. either laser-based or thin film electroluminescent edge emitting (TFEL) devices) are serially arrayed along the photoreceptor web and act to expose the photoreceptor web in accordance with cyan, magenta, yellow and black color image pixel data. A liquid toner developer module is associated with each exposure device and includes a liquid toner reservoir, a developer roll for carrying the liquid toner to a transfer point and a squeegee roll. Each developer module is fixed so as to position its developer roll at a constant prescribed distance from the photoreceptor web at the toner transfer point and to create a fluid interfacial layer between its developer roll and the photoreceptor web. In addition, each squeegee roll is maintained in constant contact with the photoreceptor web. Erasure devices and corona charging devices are positioned between the respective developer modules to enable preparation of the photoreceptor web for a subsequent exposure/development operation. A drying roll is positioned after a last developer module for fixing the imaged toner on the photoreceptor web. The exposure devices operate from either the lower side of the photoreceptor web or from the upper side; however, in the latter instance, the photoreceptor web is comprised of a transparent support and ground plane layer. Additional embodiments of the invention are disclosed which employ a dielectric powder toner and a liquid toner four pass system.