Abstract: A method and apparatus of printing with a liquid ink printhead ejecting ink in swaths on a recording medium to form an image including a plurality of dots deposited at pixel locations of a scanline. The printer deposits a plurality of dots at adjacent pixel locations on the scan line during non-consecutive swaths of the printhead to form the image. Dot interaction between dots is minimized so that no two dots are deposited adjacent to each other in consecutive depositions of the dots of consecutive swaths of the printhead. Reduction of ink bleeding, printhead signatures such as banding, and other defects caused by clogged nozzles of the printhead are reduced.

Abstract: A method is described for uniformly coating portions of the surface of a substrate which is to be bonded to another substrate. In a described embodiment, the two substrates are channel plates and heater plates which, when bonded together, form a thermal ink jet printhead. The adhesive layer is electrophoretically deposited over a conductive pattern which has been formed on the binding substrate surface. The conductive pattern forms an electrode and is placed in an electrophoretic bath comprising a colloidal emulsion of a preselected polymer adhesive. The other electrode is a metal container in which the solution is placed or a conductive mesh placed within the container. The electrodes are connected across a voltage source and a field is applied. The substrate is placed in contact with the solution, and a small current flow is carefully controlled to create an extremely uniform thin deposition of charged adhesive micelles on the surface of the conductive pattern.

Abstract: An ink cartridge for an ink jet printer has an ink supply in a housing and a printhead assembly fixedly attached thereto. The ink is contained in an absorbent material in the housing which is partitioned from the printhead assembly by a housing floor having a vent and an ink outlet. The ink flow path from the housing outlet to the printhead inlet is produced by an elongated recess in the outer surface of the housing floor and a film member bonded thereover by an adhesive not attacked or eroded by the ink. The film member has a slot therethrough to provide communication with the inlet of the printhead. The surface of the film member opposite the surface bonded to the housing floor is coated with a thermosetting adhesive which bonds to the printhead assembly surface containing the ink inlet.

Abstract: A thermal ink jet printer for printing MICR images by liquid ink droplets. The ink contains a magnetic pigment, magnetic particles, or a combination of both. An external magnetic field in the printing zone orients the magnetic pigment in a preferred direction while the printed ink droplet is still wet, so that the magnetic pigment is mobile in a liquid medium. The printed droplet is allowed to dry under the influence of the magnetic field, thereby permanently preserving the specific orientation. As a result, the remanence of the magnetic material in the images are increased and less magnetic pigment is needed for the necessary signal for MICR. This reduction in magnetic material enables the printing by a thermal ink jet printer, because nozzle clogging is avoidable.

Abstract: A pagewidth ink jet printer has a fixed, pagewidth printhead with a linear array of nozzles extending along its length and a movable cleaning and priming station adapted for movement parallel to and along the array of printhead nozzles. The cleaning and priming station has a vacuum conduit connected to a vacuum source and has an open end which confronts at least one nozzle at the nozzle array. The array of nozzles reside in a planar printhead nozzle face which has a ledge spaced from and parallel to the linear array of nozzles. The ledge extends from one edge of the nozzle face, and has a planar surface parallel to the nozzle face and a predetermined distance therefrom. The cleaning and priming station is slidingly moved in contact with the ledge surface, so that the vacuum conduit open end is maintained fixed distance from the nozzle face. The station may be moved to selected nozzles and the vacuum from the vacuum source may be varied for cleaning or priming.

Abstract: An apparatus for uniformly coating a planar substrate with an adhesive layer has a rotatably mounted sleeve with closed ends to form an internal cavity therein. The sleeve has a plurality of holes therein and its outer surface is covered by a porous layer such as a foam layer. A vacuum is applied to the sleeve cavity, while the sleeve is rotated. One surface of a polymeric film is positioned on the porous layer and held in place by the vacuum acting through the sleeve holes and porous layer. The other surface of the polymeric film contains a uniform adhesive coating. The surface of a planar substrate is tangentially transported past the polymeric film surface with the adhesive layer and in timed registration therewith, so that a nip is formed between the planar substrate and the polymeric film which transfers a uniformly thick portion of adhesive to the planar substrate surface.

Abstract: A method and apparatus for applying a coating to a front face of an ink jet print head die or print head die comprise positioning a die in a cut out in a top surface of a block such that the die extends from the top surface of the block. An applicator such as a roller or flat blade is used to apply the coating to at least an upper surface of the die as the applicator rides along the upper surface of the die. When a roller is used as the applicator, the roller has a recess corresponding to the extension of the die from the top surface of the block. The roller recess contains a piece of elastomeric material which extends to an outer portion of the roller adjacent to said roller recess. The method and apparatus facilitate transfer of a thin, uniform film of coating to an ink jet printer print head die or a completed ink jet printer print head.

Abstract: A coating for a front face of printhead in a thermal ink jet printer enables the directionality of an ink jet to be maintained for the printing lifetime of the printer. The coating controls the wetting characteristics of the front face to prevent ink accumulation on the front face. The coating comprises an epoxy adhesive resin such as EPON 1001F doped with a silicone rubber compound such as RTV 732. The coating can be provided in the form of a 24% solution of EPON 1001F in a 30:70 mixture of xylene and methyl iso-butyl ketone by weight doped with 1% by weight of RTV 732. An adhesion promoter such as an aminosilane can be included in the coating to increase bond strength between the coating and printhead front face.

Abstract: A detection circuit for detecting the existence of non-collapsing bubbles in the ink cells of a thermal inkjet printhead is connected to a heater element of an ink containing cell. The detection circuit has a sensing element of low resistance when compared to the resistance of the heater element so that printing and detecting operations can proceed simultaneously. Current in the heater element is proportional to the potential drop across the sensing element. An amplifier is used to measure the potential drop and is connected to a blocking capacitor. Non-collapsing bubbles are detected if the voltage drop across the sensing element varies from a reference level.

Abstract: Modular partial bars include a substrate bar having a length and a plurality of printhead subunits attached to only one side of the substrate bar, each printhead subunit being spaced from an adjacent printhead subunit. These modular partial bars are used as building blocks to form full width staggered array printheads. When the printhead subunits are arranged on each substrate bar so that two substrate bars are capable of forming a full width staggered array printhead, each modular partial bar is referred to as a modular half bar. One modular half bar can be stacked on another modular half bar any number of ways. For example, two half bars can be stacked with their printhead subunit containing sides facing the same direction, away from one another or towards one another.

Abstract: A method and apparatus actuates a line of printing elements to form characters on a recording medium contained on a curved surface of a platen. The printing elements are sequentially actuated, starting with nozzles located furthest from the platen and proceeding towards printing elements located closest to the platen until the actuation of all element has been performed. The line of printing elements can form a printhead which includes a plurality of nozzles arranged in at least one line having opposing ends, this line being substantially perpendicular to a longitudinal axis of the curved platen. Preferably, the line of nozzles is arranged with its center located closest to the platen and the nozzles are actuated starting at the ends of the line of nozzles.

Abstract: A thermal ink jet printer utilizes a printhead whose electrical connections to the heating elements used to expel the ink droplets has been modified to reduce the effects of parasitic resistance of the common return when a number of resistors are simultaneously addressed. The common return, formed in the same substrate level as the resistor elements, has been modified by forming and interconnecting a second common return. The resistor is connected to an input source by a low resistance connection which is formed to cross-over, or under, the second common.

Abstract: A thermal transfer printing device, including an ink donor supporting an ink meltable upon the application of a selected temperature, a printing head supporting a resistive heating element for generating the selected temperature at the ink donor, and means for bringing a final image support surface into contacting relationship with the ink donor in timed relationship to the application of the selected temperature to the ink donor including an electrically conductive heat sink layer, a heat resistant organic material having a very low thermal conductivity deposited on the heat sink layer and an array of resistors, supported on the heat resistant organic material, each resistor selectively controllable to apply a melting temperature to the meltable ink. The heat resistant organic material having a very low thermal conductivity is desirably a polyimide.

Abstract: A thermal ink jet printhead of the type which expels droplets on demand towards a recording medium from nozzles located above and generally parallel with the bubble generating heating elements contained therein is disclosed, together with fabrication processes therefor. The droplets are propelled along trajectories that are perpendicular to the heating element surfaces and from nozzles located in the printhead roof; such configuration is generally referred to as "roofshooter". Each printhead comprises a silicon heater plate and a fluid directing structural member. The heater plate has a linear array of heating elements associated addressing electrodes, and an elongated ink fill hole parallel with the heating element array. The structural member contains at least one recessed cavity, a plurality of nozzles, and a plurality of parallel walls within the recessed cavity which define individual ink channels for directing ink to the nozzles.

Abstract: An energy efficient thermoremanent magnetic imaging method and apparatus comprising a moving magnetic recording medium which is passed through a nip formed by a thermal printhead and a pressure roller, so that the magnetizable surface of the recording medium is in pressure contact with the heating elements of the thermal printhead. The recording medium is pre-magnetized prior to entry in the nip and passed through a magnetic field of lower strength and opposite polarity at the nip. Small areas or pixels of the pre-magnetized recording medium are heated by the thermal printhead in image configuration and allowed to cool in the presence of the magnetic field at the nip. The magnetic poles of the imagewise pixels are switched, forming fringe fields between the pixels and pre-magnetized background areas.

Abstract: A novel, dynamically electrostatically scanning ink jet system is provided by applying a time varying potential to an electrode located adjacent the continuous stream portion of ink emitted by a jet at a location prior to break-up of the continuous stream portion into droplets.

Abstract: Constant wavelength magnetic imaging is provided by generating a signal having a frequency proportional to the speed of a rotational recording member, multiplying that frequency up to a higher, desired recording frequency, and phase-locking the higher frequency signal to the unmultiplied lower frequency, thus synchronizing the recording frequency with the motor speed.

Abstract: Developed members having a magnetic latent image and comprising magnetic developer material in imagewise configuration corresponding to the latent image and additional magnetic developer material in background areas is rendered substantially free of excessive magnetic developing material by subjecting the member to an acceleration of magnitude sufficient to displace excessive developer material from said member in background and images areas but insufficient to adversely effect the optical density of the imagewise configured deposition of developer material. Preferably, the excessive developer material displaced from said member is removed from the vicinity of said member by application of air streams along the developed surface of said member.

Abstract: An improved magnetic interpositive imaging method is provided by creating an electrostatic latent image in a photoconductive member comprising photoconductive material dispersed in a binder; developing by touchdown development said electrostatic latent image with toner comprising from about 10% to about 60% by volume hard magnetic material; fixing said toner to said photoconductive binder; magnetizing said fixed toner; and, transferring the magnetic signal from said magnetized, fixed toner by thermoremanent transfer of magnetization to a magnetizable recording medium.

Abstract: A thermoremanent magnetographic imaging apparatus is disclosed. The apparatus includes an imaging transfer station which thermoremanently copies a graphic representation from a slave web onto the magnetizable surface of a master web. The thermomagnetic transfer is produced by exposing the slave and master webs while in intimate contact to a single intense burst of radiation from a flash lamp. The flash lamp is coaxially located within a transparent cylindrical carriage means which peripherally supports the slave and master webs during a full frame transfer process. Dual locking assemblies firmly hold the slave web and master web motionless during the thermomagnetic process to aid in the prevention of registration problems.