Agfa Gevaert Nv

Jozef L Mampaey

Serge M Tavernier

Leo N Vackier

Leo B Alaerts

Robert F Janssens

Pierre R De Roo

Frank Ruttens

Lucien P Van Der Vliet

Ludovicus P Joly

Herman J Remmerie

Andr E Verhecken

Electrostatographic developer composition

Electrophotographic apparatus incorporating a corona discharge station with corona discharge from a wire. The corona wire extends as a continuous loop between two pulleys and is advanced at a velocity in excess of the velocity of the photoconductor to be charged. The ends of the wire from which the loop is made are tied together by means of a knot, and the knot is embedded in a bead of an elastic material, preferably polyurethane.

Electrophotographic apparatus

Electrophoretic process and apparatus for developing an electrostatic charge pattern carried by a dielectric surface by progressively moving that surface through a development station and simultaneously progressively advancing a layer of liquid toner (11) comprised of toner particles dispersed in a carrier liquid, through that station in proximity to said charge-carrying surface, (3), and imposing an electric field bias to cause or promote selective image-wise movement of toner particles through said liquid at said development station and deposition thereof on said charge-carrying surface in a pattern representing said electrostatic charge pattern, wherein said layer of liquid toner contains toner particles in a concentration of from 2 to 25% by weight, and including the step of applying a film of a substantially toner-free non-polar liquid which is miscible with the carrier liquid of said liquid toner and which has a specific conductivity lower than 0.2 nS/m over said liquid toner layer (11) in such manner and at such a rate that each increment of such toner layer arrives at the development station, substantially free from turbulence and covered by the film of substantially toner-free liquid, the thickness of the film being such that at the development station it just makes contact with the chargecarrying surface.

Electrophoretic development of electrostatic charge images

Method and apparatus for transferring an electrostatically deposited electrophoretic toner image including the step of transferring image-wise deposited toner particles dispersed in a stratum of carrier liquid having a volume resistivity of at least 10.sup.9 ohm.cm and a dielectric constant less than 3 from an electrically insulating surface onto a receptor element by contacting said liquid stratum while carried on the insulating surface with a surface of the receptor element while applying an electric field such that the receptor element has a polarity opposite to the polarity of the toner particles to effect such transfer, characterized in that before the image-wise liquid stratum touches the receptor element the carrier liquid stratum is given a corona-charge treatment by a corona-charge unit whereby said liquid stratum is charged to a polarity opposite to the charge of the toner particles.

Method and apparatus for the transfer of an electrostatically deposited

Method of transferring a liquid xerographic toner image between two elements one of which is a flexible sheet advancing along a straight line path and the other is advancing synchronously along an arcuate path around a fixed axis which path at one point is in close spaced proximity to the straight line path. The flexible element is supported by its margins alone and its unsupported region is subjected to a biasing force to deflect the same toward the other element and bring a liquid toner image, which is previously deposited, e.g., by developing an electrostatic charge pattern with liquid toner, on one of the mutually facing surfaces of the two elements, into direct contact with both element surfaces maintaining such surfaces apart. During the passage of the two elements through the point of close proximity an electrical potential gradient is applied across the elements during such passage to transfer the liquid toner from the surface on which it is deposited to the other element surface.

Method for transferring xerographic images

A xerographic liquid toner image is transferred onto an image-receiving sheet carried along an arcuate path, e.g., on the peripheral surface of a rotating drum from the underside of a flexible sheet, e.g., a photoconductor sheet, while the flexible sheet is suspended by its margins from a moving carriage. The carriage is guided generally horizontally along a path above and proximate to the top of the drum periphery at a level such that the unattached central part of the flexible sheet, which is free to sag relative to its margins, is supported by the liquid toner image itself, out of contact with the image-receiving sheet, as the two sheets pass through an image transfer zone adjacent the top of the drum periphery.

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Kontich, Belgium

Jozef L Mampaey