Abstract:
A printing system for printing multiple colors on a sheet of print media includes an electrophotographic printer having a photoconductor drum and a transfer roller configured to interact in co-rotation with the drum during transfer of a color image plane from the drum onto a sheet of print media passed therebetween. A paper drive sheet feeder system is included which has a grit shaft extending generally transverse of a paper travel path, a first pinch roller configured to interact in co-rotation with the grit shaft along a first edge of a sheet of print media, and a second pinch roller configured to interact in co-rotation with the grit shaft along a second edge of the sheet of print media. The grit shaft is driven in rotation to drive the sheet of print media along a bidirectional sheet travel path such that a plurality of different colored image planes is superposed onto the sheet of print media in accurate registration therebetween. A method for printing multiple colors is also described.
Abstract:
A color printer incorporating the invention hereof includes an ionographic image projection head which employs AC and DC potentials to provide an ion pool from which ions may be projected onto a movable dielectric surface. Plural developer modules are arranged about the dielectric surface, each developer module including an ion imaging head and a color toner module. Each developer module, after ion-beam imaging the movable dielectric surface, develops the charge image on the dielectric surface by bringing it into contact with a single color toner module. A processor controls each ionographic image projection head and each associated toner module to immediately apply the color toner after imaging of the dielectric surface. A transfer station is located downstream from the plural developer modules and enables transfer of the full color toned image from the dielectric surface to a sheet after a single pass of the dielectric surface past the plural developer modules.
Abstract:
Liquid toner conditioning apparatus for use in an electrophotographic color printer and including a stabilizing roller positioned adjacent to the surface of a photoconductive drum and operative for transforming discrete color toner particles on the surface of the drum into a stabilized unitary polymeric film structure which may be directly transferred onto an adjacent print medium. Advantageously, the stabilizing roller will include an inner core member which may be heated as well as connected to a source of either AC bias or DC bias or both. This stabilizing and toner conditioning roller further includes a soft elastomeric roller cover positioned around the periphery of the inner core member and has a smooth outer surface which makes direct contact with the developed toner layers on the surface of the adjacent photoconductive drum.
Abstract:
An ink composition is provided for an ink-jet printer, preferably a thermal ink-jet printer. The composition comprises about 5 to 40 wt % glycol, about 60 to 90 wt % water, about 0.001 to 10 wt % polymer blend and about 1 to 7 wt % dye. The polymer blend includes both uncharged and charged monomeric units.The glycol and polymer blend act to form a soft plug that forms in the orifice of the ink-jet pen. The soft plug prevents further evaporaion of water, but unlike a hard plug, is readily blown out upon firing. The charged units in the polymer blend contribute to water fastness and light fastness of the dye on paper. Further, by employing appropriate functional groups in the polymer blend, chemical degradation of the ink dye can be retarded on acid or alkaline papers.
Abstract:
Lower resolution source data is synthesized to a higher resolution format for subsequent rendering on a lower resolution output device. Synthesis occurs by selecting or generating and using a synthesis template that represents a configuration of a plurality of pixel data in the higher resolution format into which the lower resolution source data is to be synthesized. A working or active pixel is identified from the lower resolution source data, a synthesis template is selected, and then the synthesis template pixel data is substituted for the working pixel for rendering on the output device. The synthesized higher resolution data is rendered in a manner such that dots represented by the synthesized data are formed interstitially relative to scan lines of the given lower raster/resolution capability of the output device. The working pixel is identified in the lower resolution data by recognizing a configuration of a plurality of pixel data adjacent the working pixel. The synthesis template comprises at least a two by two cell matrix for pixel placement in the higher resolution format. The synthesis template pixel placement is formed to provide an apparent merge of the pixel data in the higher resolution format with the adjacent pixel data of the lower resolution format data.
Abstract:
The present invention relates to image forming devices, fusing assemblies and methods of forming an image. According to one aspect of the invention, an image forming device includes a housing including a media path configured to guide media in a downstream direction within the housing; an input device configured to receive an image; a developing assembly adjacent the media path and configured to provide developing material; a sensor adjacent the media path and configured to determine a qualitative characteristic of the media and to generate a signal indicative of the qualitative characteristic; and a fuser adjacent the media path and configured to adjust a fusing parameter responsive to the signal and to fuse the developing material corresponding to the image to the media and according to the fusing parameter.
Abstract:
The present invention includes image forming devices, imaging assemblies, sensors, and methods of forming an image. One aspect of the present invention provides an image forming device including a housing configured to guide media along a media path; an input device configured to receive an image; a sensor adjacent the media path and configured to monitor the media and to generate a signal responsive to the monitoring; and an imager adjacent the media path and configured to provide developing material corresponding to the image upon the media according to an imaging parameter and to adjust the imaging parameter responsive to the signal.
Abstract:
The invention is a negative charge director for liquid electrographic toners. The charge director comprises a very weakly associating, charged functional group covalently bonded in the resin coating of the toner particle, and a very strongly chelating, preferably neutrally charged, molecule dispersed in the liquid phase to achieve charge separation. The weak association site on the resin is prepared, via well-known ion-exchange chemistry, in the metal form desired. Preferred metals are those with no regulatory, health or environmental issues, such as K+, Na+, Ca.sup.2+, Al.sup.3+, Zn.sup.2+, Zr.sup.4+, Mg.sup.2+, ammonium (NH.sub.4 +), and organic cations.The cation-associated resin is brought into dispersion with the solution phase chelating molecule. When this is done, the equilibria that compete for the cation are such that it is released from the resin and bound in the chelate. The toner particle is left with a net negative charge which is permanent, but which is balanced by an equal, opposite charge on the chelated cationic species in the continuous phase. Preferably, there are no other sources of charge in the dispersion, and there is no excess of charge carriers in the continuous phase which would interfere with development.
Abstract:
A method of data processing is described for generating a screened bitmap in an adaptive manner. The page being printed is subdivided into a plurality of smaller areas, and the optimal screening method is selected based on the content of the data being processed. Areas of the page that primarily comprise of graphic elements and/or fonts are screened as part of the rendering process, while areas that are primarily continuous tone elements are screened as a secondary step after the rendering process.
Abstract:
A system and method for electrophotographic printing an image with a plurality of toners, where the plurality of toners includes toners that are attracted to either a first charge potential or a second charge potential. The electrophotographic system includes a photoconductive surface that is charged to the second charge potential. A laser selectively discharges the photoconductive surface to the first charge potential in accordance the image to be printed. Those toners that are attracted to the first charge potential are applied to the photoconductive surface, wherein the toners are electrostatically attracted to those areas of the photoconductive surface that are at the first charge potential. The photoconductive surface again charged to the second charge potential. The photoconductive surface is again discharged to the first charge potential in accordance with those areas of the image to which those toners that are attracted to the second charge potential are to be repelled. Those toners that are attracted to the second charge potential are applied to the photoconductive surface, wherein the toners are electrostatically attracted to those areas of the photoconductive surface that remain at the first charge potential. Finally, the image is transferred to a receiving surface.