Eastman-kodak Company

Heidelberger Druckmaschinen Ag

Albert V Buettner

David Steven Weiss

Anne F Lairmore

Marie B O'Regan

Jeffrey R Murray

Louis J Sorriero

Rodney Ray Bucks

Lawrence E Contois

Dennis Roland Fronheiser

Carl E Cowan

A multi-active electrophotographic charge generation element comprises a conductive support, a charge generation layer (CGL) disposed on the conductive support, and a charge transport layer (CTL) disposed on the charge generation layer. The charge generation layer (CGL) includes a charge-generation material comprising an aggregated or crystalline form of a first dye or pigment and a first polymeric binder. The charge transport layer (CTL) comprises at least one charge-transport agent, a second dye or pigment having absorption in a selected spectral region that at least partially overlaps the absorption of a dissolved non-aggregated or non-crystalline form of the first dye or pigment, and a second polymeric binder. The second dye or pigment in the charge transport layer absorbs radiation in the selected spectral region that is incident on the charge transport layer, thereby shielding the charge generation layer from that radiation and mitigating visible radiation-induced photofatigue.

Electrophotographic element protected from photofatigue induced by visible light

The surface of an electrostatic recording member in an electrophotographic recording apparatus is charged to a standard primary charge V . The standard primary charge on the recording member is then modulated using a first test exposure E to form a first exposed test area, and using a second test exposure E to form a second exposed test area. A first test surface potential V is measured in the first exposed test area and a second test surface potential V is measured in the second exposed test area. A measured intrinsic sensitivity b associated with the recording member is calculated using V and V . A measured intrinsic toe d associated with the recording member also is calculated using V and V . A corrective charge parameter V is calculated using d , and a corrective exposure parameter E is calculated using b and d . V is then adjusted to equal V , and E is adjusted to equal E .

Electrophotographic recording process control method and apparatus

A multiactive photoconductive element exhibiting reduced black spots in discharged area development systems. The element includes (A) a conductive layer, (B) an aggregate charge generation layer in direct physcial contact with the conductive layer and (C) a charge transport layer. The charge generation layer contains (i) a binder an adhesive polymer. The charge transport layer contains a binder according to formula II: ##STR1## wherein the Ar, R.sup.1, R.sup.2, R.sup.7, R.sup.8, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.9, R.sup.10, R.sup.11, and R.sup.12 and x are defined in the specification.

Electrophotographic elements exhibiting reduced numbers of black spots

Techniques are provided for regenerating photoconductor elements, particularly those of the unipolar, homogeneous type. These techniques utilize a low-voltage to moderate-voltage reverse charge. Also provided are new photoconductor elements useful in the practice of such techniques.

Photoconductor element, regenerating methods and elements useful therein

An improvement in the method and apparatus for producing a multi-color electrophotographic image wherein an electrophotographic medium can be used for multiple charge-expose cycles without the accumulation of trapped charges which can result in an increase in toe voltage. The invention provides for the charging, exposing and toning of the medium to produce a first color visible image. The carrier is then returned to the first position to repeat the foregoing steps to charge, expose and tone to produce a second color visible image. Prior to the second charging step the medium is reverse charged and trapped charges are neutralized to substantially revitalize the medium to a condition closely resemblng its unused condition to substantially eliminate the rise in toe voltage.

Growing community of inventors

Rochester, NY, United States of America

Albert V Buettner