Abstract: An ink jet print head for a continuous ink jet printer includes an orifice plate defining an elongated array of ink jet orifices, an ink manifold for supplying ink to the orifices in the orifice plate, and a shear mode piezoelectric transducer mechanically coupled to the orifice plate for vibrating the orifice plate sufficiently uniformly along the length of the array of ink jet orifices to achieve synchronous stimulation. The use of a shear mode piezoelectric transducer eliminates mode cross coupling thereby allowing high frequency stimulation in long ink jet print heads.

Abstract: A front surfaced mirror having a reflective surface of Tantalum Aluminide for reflecting light beams, especially, but not limited to those having wavelengths in and near the infrared and ultraviolet bands.

Abstract: A method of fabricating a catcher assembly for an ink jet printer replaces the standard catcher assembly with an assembly comprising at least one capillary, typically a glass capillary. Initially, a charge plate is provided. Then the capillary or capillaries are provided, the capillaries having an axis parallel to the charge plate. The external surface of each capillary comprises a catcher face, and establishes a well defined radius and surface finish.

Abstract: An ink jet ink composition comprises a liquid vehicle, a single dye component, a surfactant and a glycol. The dye is water soluble and selected from the group consisting of Direct Dyes, Acid Dyes and Food Dyes, and preferably from the group consisting of Direct Yellow 86, Acid Red 249, Acid Red 92 and Direct Blue 199. Concentration of the dye is preferably in the range of 1% to 2% by weight. Using the ink composition of the present invention, images are generated by a continuous stream digital color press ink jet printing apparatus. In a preferred embodiment, to optimize runnability and jet straightness, the digital color press employs a gold orifice plate having an orifice diameter in the range of 0.7 to 0.8 mil.

Abstract: A piezoelectric ink jet print head includes a body of piezoelectric material defining a plurality of parallel open topped channels having electrodes on opposite walls thereof. A top cover having a pattern of parallel conductors congruent with the open tops of the parallel channels is secured to the body by reflow soldering the conductors to the electrodes. The resulting solder bond is very stiff, thereby improving the performance of the print head, and the conductors provide convenient electrical contact to the electrodes.

Abstract: A drop on demand ink jet print head includes air bubble removal channels having a larger cross sectional area than the ink jet printing channels. In operation, the air bubble removal channels are operated to remove air bubbles from an ink manifold prior to ink jet printing.

Abstract: A printing module for an ink-printing system, interchangeably attached in a holder, consists of an ink storage container with an ink-printing head arranged on it. The ink storage container contains a housing with an assembly surface for an ink-printing head, as well as an ink collection region directly adjacent to the assembly surface. The ink collection region is covered over a large area with a filter element made from woven plastic fabric. Furthermore, a storage element made of a micro-channeled, ink absorbing and releasing material is arranged in the housing, which is in direct contact with the filter element over a large area.

Abstract: A multiplex drop ejection construction for a drop-on-demand, ink jet printer. The construction includes a support substrate; a first circuit portion having branches that include a resistive heater element and a diode device formed in spaced relation on the substrate. A dielectric passivation layer overlies the first circuit portion except at the discrete terminal regions of the first circuit portion branches. A second circuit portion comprising a plurality of multiplex electrode lines overlies the passivation layer and includes connection sections extending through the passivation layer into contact with terminal regions of the first circuit. A second passivation layer overlies the second circuit portion, but not the resistive heater elements.

Abstract: An improved protective construction for a bubble jet print head device of the kind having a substrate with a plurality of separately addressable resistive heater portions that are formed by address and common electrodes. The protective construction includes a first layer of dielectric material formed over the heater portions, a second layer of metal formed over the first layer, and a third layer having a physically hard and chemically inert outer surface portion overlying the second layer.

Abstract: An improved orifice construction for a bubble jet print head of the kind including a plurality of electrode-addressed resistive heater elements predeterminedly spaced in a linear array on a support substrate. Such construction includes a plurality of separator means extending up from the substrate surface at positions precisely between respective heater elements and an orifice plate fixedly mounted above the substrate and having a linear slot, of orifice width and linear array length, aligned over the heater elements and their intermediate separator members. The slot edges and separator members cooperate to define a plurality of discrete orifices that are precisely located vis a vis respective heater elements.

Abstract: An improved heater/electrode construction for a bubble jet print head of the kind having discrete ink heater elements formed of electrically resistive material and a plurality of address electrode pairs formed of electrically conductive material and electrically contacting opposing edge regions of respective heater elements. The heater element resistance increases from its center outward and the electrode ends are spaced from the bubble formation region to provide, in a drop ejection condition, a flat slope temperature profile along the current flow path through the bubble formation zone.

Abstract: A bubble jet print cartridge assembly includes an ink supply housing having an ink reservoir and a fluid block component capping the ink reservoir and having ink passages extending from the reservoir to an ink outlet(s). A drop ejection chip comprising a substrate having resistive heater elements and electrode leads is attached to the outer side of the fluid block component with a peripheral chip edge(s) adjacent the ink outlet(s). A raised ink barrier fence formed on the outer surfaces of the fluid block and chip surrounds the heater elements and ink outlet(s). The fence has a height extending above the top surface of the supported chip and an orifice plate member is affixed at its periphery to the top of the barrier fence so as to enclose the region surrounded by said barrier fence.

Abstract: An orifice plate assembly for use in continuous ink jet printers includes a linear orifice plate having formed therein at least one linear array of orifices extending from a first end region to a second end region. The orifice plate has a main body portion which tapers gradually in thickness (t) along the length of the plate from the first end region to the second end region. The orifice plate is mounted so as to have an effective width (w) which tapers from the first to second end region. The relation t.div.w remains approximately constant along its length dimension.

Abstract: There is described a printing head useful in an ink-jet printer to print on a recording medium, comprising jet forming means for forming spaced drops of ink, charging means adjacent the forming means for inducing an electric charge in selected some of the drops, the charging means being mounted on an electrically non-conductive plate, and drop-catcher means for catching the charged drops. The drop-catcher means is integral with the plate mounting the charging means, and is disposed downstream from the charging means.

Abstract: In a continuous ink jet printer, the ink pressure is adjusted by detecting the fractional charge imparted to satellite drops, and adjusting the ink pressure as a function of the detected charge.

Abstract: An ink jet print head of the type having an elongated rectangular print head body that is vibrated at its resonant frequency to stimulate formation of ink drops is provided with a rigid ink supply tube connected to the print head body at a nodal point and is mounted by the rigid supply tube.

Abstract: A stimulation arrangement for a fluid jet printer. A pair of piezoelectric crystals are mounted on opposing surfaces of a high acoustic Q solid member and are excited for periodic lengthening at the frequency of desired stimulation. This creates shear waves in the surface of the high Q member. The high Q member is configured in such a fashion that it transforms the shear waves into stationary compression waves which drive an orifice plate and thereby stimulate fluid filaments being generated by the jet printer. The high Q member may be a rod-like stimulator supported for localized contact against a filament forming orifice plate or it may comprise support structure for the orifice plate.

Abstract: In a continuous ink jet printer, the stimulation amplitude is adjusted by sensing the stimulation amplitude at which infinite satellites are first produced, and adjusting the stimulation as a function of the sensed amplitude.

Abstract: There is described an acoustic absorber for an ink jet printer using a waveguide to generate ink drops. The absorber comprises a sheet of elastomer disposed on the orifice plate between the orifice plate and the charge plate of the printer, and a diffuser disposed in contact with the elastomer and between the elastomer and the charge plate, the diffuser having an acoustic impedance of at least 3.times.10.sup.7 kg/m.sup.2 sec. The length and width of the elastomer sheet and the diffuser are such as to absorb the vibrations from the orifice plate and prevent reflections at the end of the waveguide.

Abstract: Ink jet printing apparatus having a cleaning system whereby ink is supported proximate the droplet orifices, the charge plate and/or the operative catcher surface and ultrasonic cleaning vibrations are imposed on the supported ink mass. Such cleaning can be implemented with ink cross-flowing through the print head cavity and/or in cooperation with a varying pressure differential across the charge plate, which cause ink to oscillate inwardly/outwardly within the orifices.