Xerox Corporation

Oscar G Hauser

Frederick R Ruckdeschel

Gerald A Domoto

Robert W Anderson

Lawrence M Hart

Charles A Whited

Fong-Jen J Wang

Joseph C Mammino

Frank C Genovese

Richard L Schank

Donald S Sypula

Dennis A Abramsohn

Fred W Schmidlin

Steven B Bolte

Dusan G Lysy

Raymond W Stover

Richard F Koehler, Jr

Deborah J Nichol-Landry

John F O'Brien

Robert E Gary

Kallis H Mannik

Thomas Meagher

F James Wang

An enhanced image conditioning process for liquid ink development assists in achieving better developability and metering capability, especially for the cases where highly viscous developer fluids are used. By selectively heating the developer fluid in the vicinity of the development zone and/or the metering zone, the viscosity of the liquid is reduced, and hence better developability and a thinner film with higher solid content for the developed image can be obtained. Another benefit of lowering the viscosity of the developer fluid is that the developer fluid can be applied and metered at a faster rate than higher viscosity fluids. Liquid ink developability control by controlling ink temperature is advantageous over conventional methods of xerography.

Liquid ink development control

The undesirable image defect of dragout of liquid ink development (LID) toned images generated from the development zone, formed by an imaging member and a metering/development member, can be prevented. Background development of the toned images is suppressed in an image enhancement zone. With the aid of an enhanced electrostatic field, created by an electrode biased at a voltage other than normal development bias in the metering zone, the toned layer can resist higher viscous forces. Image dragout, due to the viscous shear from liquid ink, can therefore be eliminated.

Liquid ink development dragout control

A single image development and conditioning apparatus is disclosed for removing excess liquid carrier from a developed image developed in a liquid immersion development machine using liquid developer material having a first toner concentration. The single image development and conditioning apparatus includes a first zone located downstream of a coating device relative to a direction of movement of a surface bearing the developed image, a second zone located downstream of the first zone, and a third zone located downstream of the second zone. The first zone includes a first biased electrode for partially removing charged solid toner particles from background areas of the developed image. The second zone includes a second biased electrode for completing removal of charged solid toner particles from the background areas, and the third zone includes a third biased electrode. The first, second and third zones are arranged and biased so as to enable (i) removal, from the background areas, of liquid developer material consisting of liquid carrier and charged solid toner particles, and (ii) removal, from the image areas only, of excess carrier liquid, thereby creating a resulting toner image having a toner concentration significantly higher than the first toner concentration of the liquid developer material.

Liquid immersion development machine having a multiple zone image

An apparatus for fusing toner to a surface of a sheet which includes tandem sets of heated and pressure rollers. A screw drive, solenoid or other means is used to urge the roller sets to make uniformly distributed contact on the sheet passing between the heated and pressure rollers. Each set of rollers may be selectively employed so as to vary temperature, dwell time, pressure and other performance parameters at the fusing nips of the sets of heated and pressure rollers. The path of a sheet moving through the fuser need not be altered to employ the varied fusing performance combinations, also reducing the likelihood of sheet jamming and misfeed. Fuser oil applicators may also be employed so as to apply oil to each heated roller as it engages the sheet.

Multilevel fusing apparatus

In an electrophotographic imaging device, in which an electrostatic image is formed and developed on a first support to form a toned image, and the toned image is transferred to a second support substrate and subsequently to a final support, and in which to form color images, a succession of toner images are superposed on each other by transfer from one or more first support to the second support, transfer efficiency is enhanced and color consistency is improved by providing an order of superposition which places the toner having the greatest residual mass/area dependent color instability in a position of being sandwiched between or protected by two or more other toner images whose color contribution to gray balance is not as greatly dependent on mass per unit area. Thus, during transfer, the sandwiched or middle layer(s) will retain integrity.

Multilayer toner transfer ordering

An ionographic imaging member has a conductive layer overcoated by a charge accepting layer. Overcoating layers of acrylate, polycarbonate, polyester, polyurethane, acrylic homopolymer or copolymer and the like are provided. Blocking layers may be provided for preventing charge injection and reducing surface charge decay and bulk charge trapping. The charge accepting layer may be doped with a charge clocking material for preventing charge injection. The overcoating and blocking layers may be one and the same.

Blocking and overcoating layers for electroreceptors

In an ionographic device projecting a modulated stream of ions in imagewise fashion towards a moving imaging surface, including an ion printing head having an ion chamber supporting a coronode held at a voltage V.sub.C to produce ions for deposit on an imaging surface and a modulation channel extending from the ion chamber towards the imaging surface through which a stream of ions is directed for imagewise modulation by a plurality of modulation electrodes, electric field distribution within the ion chamber is controlled by selectively varying voltages along the surface regions of the ion chamber to different voltage levels, in an arrangement causing focusing of ion density in the area of the ion chamber adjacent to the modulation channel. An increased ion density in the area of the ion chamber adjacent to the modulation channel assists in providing an increased corona current at the output of the device.

Method and apparatus for increasing corona efficiency in an ionographic

In an ionographic device projecting a stream of ions towards a moving imaging surface, modulated in imagewise fashion, one or more control electrodes may be arranged adjacent to the path of the ion stream and between the source of the modulated ion stream and the imaging surface, biased with a voltage preventing previously deposited charge from perturbing the trajectory of subsequently projected ions to limit the amount of ion beam deflection caused by the presence of electrostatic charge patterns on the electroreceptor.

Method and apparatus for controlling ion trajectory perturbations in

Apparatus and method for reducing toner contamination in an electrostatographic reproducing machine are described wherein at at least one housing which performs an operation on an imaging surface bearing an electrostatic latent image involving charged toner particles has at least one electrode extending across the width of and spaced from the imaging surface at at least one exit portion through which air normally flows from the housing to other portions of the machine, the electrode being electrically biased to a polarity and magnitude selected relative to the charge on the imaging surface to create an electric field barrier in the exit portion sufficient to repel the charged particles in the exiting air back into the principal portion of the housing substantially without restricting the air flow from the exit portion. In a preferred embodiment the electrode is positioned substantially parallel to the imaging surface. This electrostatic seal arrangement may be used in development or cleaning housings and a preferred mode is used in a magnetic brush development housing at the imaging surface entrance portion where the magnetic brush moves in a direction counter to the direction of the imaging surface.

Toner containment method and apparatus

Electrostatographic apparatus comprising an imaging surface with an electrostatic transfer evice to transfer toner particles to a receiving sheet and an apparatus to detack the sheet from the drum comprising a plurality of conductive fibers extending cross the rear side of the receiving sheet which are spaced from the sheet and have applied thereto a low voltage direct current potential of a polarity opposite the polarity on the receiving sheet and sufficient to cause air breakdown between the receiving sheet and the end of the fibers to provie a controlled neutralization of charge on the receiving sheet to a potential level above zero and thereby separate the receiving sheet from the drum by virtue of its own weight and beam strength.

Detacking apparatus

An electrophotographic printing machine in which a developer roller transports a developer material comprising carrier granules and toner particles closely adjacent to an electrostatic latent image recorded on a photoconductive surface so as to develop the latent image with the toner particles. A member is positioned closely adjacent to the developer roller to attract the toner particles to at least one surface thereof. A beam of energy is transmitted through the member onto the surface on which the toner particles adhere. The internal angle of incidence of the beam of energy is greater than the critical angle of incidence of the member. The intensity of the beam of energy internally reflected through the member is detected. A signal indicative of the quantity of toner particles attracted to the surface of the member is generated. The signal is processed and a signal transmitted indicating the end of the useful life of the developer material.

Developer material end of life sensing

This invention is directed to a developer composition comprised of a resin, a colorant such as cyan, magenta, yellow, or mixtures thereof, and a single carrier. In one embodiment there is combined with a single carrier material, such as a steel carrier or a nickel berry carrier, a cyan toner, such as a styrene/n-butyl methacrylate resin, and copper tetra-4-(octadecylsulfonomido) phthalocyanine, a magenta toner material comprised of styrene/n-butyl methacrylate copolymer resin and 2,9-dimethyl substituted quinacridone, and/or a yellow toner material comprised of styrene/n-butylmethacrylate copolymer resin and a diaryldide yellow 3,3-dichlorobenzidene aceto acetanilide. The developer composition is useful for developing color images in an electrophotographic imaging system. In this system a photoreceptor material contained therein is charged, imagewise exposed, followed by development, transfer of the developed image to a suitable substrate such as paper, and permanently fixing the developed image, by heat for example, to the substrate.

Blended toners of functional color

This invention relates to an improved color developing composition, the composition being comprised of toner resin particles, with each of said particles containing therein up to four pigments, and a single carrier. Suitable pigments include magenta, cyan, yellow or white, and/or mixtures thereof. The pigments are present in an amount of from about 1 percent (part) to about 20 percent by weight. Such compositions are useful in obtaining color images utilizing a single pass xerographic imaging system.

Toners, developers for use in a single pass color image development

An apparatus in which at least a pair of developer rollers deposit toner particles on an electrostatic latent image recorded on a photoconductive member to render it visible. One of the rollers rotates at a first tangential velocity being spaced a first distance from the photoconductive member. The other roller rotates at a second tangential velocity being spaced a second distance from the photoconductive member. The second tangential velocity is greater than the first tangential velocity with the second distance being less than the first distance.

High speed magnetic brush development system

A reproducing machine in which a member has successive latent images recorded thereon. The reproducing machine includes a pair of developer units. One developer unit is located in the operative position in the reproducing machine with the other unit being remote therefrom. Each developer unit contains different colored particles. Color changes are achieved by interchanging developer units to develop one latent image with particles of one color and the other latent image with particles of the other color.

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Rochester, NY, United States of America

Oscar G Hauser