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: A pumping apparatus comprises a piston/cylinder assembly mounted between two laterally spaced end cap sections attached to base means and including spring-loaded valve devices. A piston rod is movably supported in and extends outwardly from one of the end cap sections. A manually operated linkage mechanism effects axial longitudinal movement of the piston rod and a support mechanism maintains longitudinal axial alignment of the piston rod during its longitudinal axial movement. The longitudinal movement of the piston rod operates in concert with the spring-loaded valve devices to pump fluid manually when the pumping apparatus is positioned in any angular disposition with respect to the horizontal.

Abstract: A method of gray scale printing of dots of one or more colors into pixels and in a controlled ordered sequence into a plurality of super pixels defined by a given number of said pixels, characterized in that: one or more levels of dot loading are used to achieve different values of gray level in a multiple-level gray table. This generic method is applicable to both ink jet and electrophotographic printing species of this invention.In one electrophotograpic printing species of this invention, there is disclosed a method of electrophotographic color printing which includes mixing a plurality of colors in a single plane and in dot-next-to-dot (DND) pixels within a plurality of super pixels to produce a color image, whereby the sum of the multi-color dots printed in any super pixel is limited to the number of subdivided individual pixels therein, thereby assuring dot-next-to-dot (DND) always printing of said colors in a single plane.

Abstract: A method for reducing "grainyness" or color contrast in color imaging systems and simultaneously reducing or eliminating paper cockleing of media printed by ink jet printing. The method involves determining the maximum allowable ink print density necessary to reduce or eliminate paper cockleing in the printed media and then providing tight control of the selection of gray scale ink drop count and associated dye loading in relation to this maximum allowable print density. Using this method, pixels are selected and printed in such a manner as to maximize the uniformity of ink distribution on the printed media.This method will work using either a variable drop size or a fixed drop size with variable dye loadings. It will also work with most error diffusion or dithering schemes presently used and available in the image processing arts.

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: This application is directed to an ink jet pen having an ink supply housing which includes a primary ink reservoir (30) and a secondary ink reservoir (26). A balancing capillary member is positioned within the ink supply housing and includes ink flow path (20, 24) which extends between the primary ink reservoir (30) and the secondary ink reservoir (26). This capillary member is operative to draw ink from the primary ink reservoir (30) and into or toward the secondary ink reservoir (26) by capillary action as temperature and pressure within the primary ink reservoir increases. Conversely, when temperature and pressure in the housing decreases, ink will be drawn back into or toward the primary ink reservoir (30). In addition, the primary ink reservoir (30) is connected by way of a suitable ink feed path to an ink jet printhead (32) for supplying ink to the printhead during an ink jet printing operation.

Abstract: The specification describes thermal ink jet (TIJ) processes and device structures produced thereby wherein either heater resistors or heater resistor-diode combinations are constructed vertically upward from a common supporting substrate. A lower or first metal level conductor pattern provides one part of an X-Y matrix multiplex connection to the resistor/diode components, and a second, upper metal level conductor pattern forms the second part of the X-Y matrix multiplex connection. In this manner, the multiplex drive circuitry for the TIJ printhead resistors/diodes may be fabricated (integrated) directly on the thin film resistor (TFR) printhead substrate. Additionally, the second level metal conductors which overlie the resistive heater and diode elements also serve as a barrier shield to ink corrosion and cavitation wear.

Abstract: The present invention is directed to a compound bore nozzle plate for a thermal ink jet printhead and is manufactured by electroforming nickel onto a nickel substrate which has been masked by a plurality of mask segments of predefined geometry. This geometry consists of a plurality of base segments upon which have been formed a corresponding plurality of post segments of greater vertical dimension and smaller lateral dimension than the base segments. This mask geometry enables greater center-to-center orifice spacing to be achieved without unacceptably reducing the thickness and structural integrity of the nozzle plate.