Abstract: A photoconductive imaging member containing a photogenerating layer, and a charge transport layer containing a binder and a polyol ester.

Abstract: A photoconductive imaging member containing a photogenerating layer, and a charge transport layer containing a binder and a suitable polyimide, and more specifically, an amorphous polyimide.

Abstract: This invention relates to an electroforming device and a process used to electroform a metal layer on an inner surface of a female mandrel. The electrolytic solution flows only through an electrolytic solution passageway that defines the inner surface as the walls of the passageway. The mandrel may include more than one electrolytic solution passageway, or multiple mandrels may be used in a sequential order to mass produce the electroforms.

Abstract: There is disclosed an apparatus for depositing metal on a member comprising: (a) a first electrode comprising a first corrugated side; (b) a second electrode having the same polarity as the first electrode and comprising a second corrugated side, wherein the second corrugated side is disposed opposite the first corrugated side, and spaced therefrom; (c) a channel defined by the first corrugated side and the second corrugated side for movement of the member therebetween, wherein the channel has a plurality of alternating expansive areas and constrictive areas; and (d) a conveyor device for transporting the member through the channel.

Abstract: A heat sink for a thermal ink jet printhead has improved resistance to the corrosive effects of ink by forming a chromate film on a copper plated metal substrate. In one described embodiment, a thermal ink jet printer is formed by bonding together a channel plate and a heater plate. Resistors and electrical connections are formed in the surface of the heater plate. The heater plate is bonded to a heat sink comprising a zinc substrate having a copper film plated on one surface. The copper plated heat sink is immersed in a chromic acid and water bath. Metal anodes are placed within the bath and a field is applied for a period of time sufficient to form a polymeric chromate film on the copper plated surface. The chromate film has improved resistance to ink corrosion and exhibits a stronger printhead to heat sink bonding strength.

Abstract: A composite resinold/graphite/diamond blade is described having enhanced precision cutting properties. The blade is made by assembling several layers, each layer comprising a veil of non-woven graphite fabric impregnated with a mixture of diamond particles blended into a phenolic resin. Layers are built up in sandwich fashion. In one embodiment described, four layers are formed and, in a heating compression molding operation, the sandwich is compressed into a composite blade having a diameter of 4.7 inches with a thickness of 0.011 inch. The final blade is formed by a die cut and lapping process. The layered construction yields a blade with more consistent cross-section and improves blade wear symmetry. In another embodiment, the layers are tailored to have a grit concentration of the diamond/resin mixture at the periphery or cutting edge.

Abstract: An electroforming/electrodeposition process and apparatus includes a first electrode, a second electrode spaced from the first electrode, a channel defined by the first and second electrodes and at least one electrically nonconductive or poorly conductive shield disposed adjacent at least one electrode. The shield(s) define(s) a region of the channel wherein the surface of a mandrel placed in that region experiences substantially uniform current density. The apparatus may contain additional electroforming/electrodeposition and/or other steps and may be arranged in a carousel apparatus with one or more mandrels to permit continuous operation of the apparatus.

Abstract: A method of dicing a printhead wafer containing a plurality of individual print elements into discreet elements. A back side relief feature is formed on the bottom front edge of a thermal ink jet print element from a heater side during a first dicing cut, followed by a second dicing cut from a channel side of the wafer to form a front face nozzle. The back cut feature enables front face maintenance by a wiper blade or other maintenance operation, provides a pocket for excess die bonding adhesive during manufacture, and reduces front face chipping during dicing caused by the saw blade contacting the die wafer mounting media and becoming contaminated. The relief feature may be a square step feature or a beveled back cut feature and may additionally be located on a top front edge of the print element.

Abstract: A resinoid dicing blade having approximately a 20% by volume porosity structure is coated and impregnated with Teflon.RTM. by a process which impregnates the resinoid blade with Teflon.RTM. to about 0.3 to 0.5% by weight. The Teflon.RTM. impregnated dicing blades not only reduces nozzle chipping when bonded silicon wafers are separated into a plurality of individual printhead die, but blade life is significantly increased.

Abstract: An apparatus for depositing metal which provides a brushless electrical current continuity between a member, such as an electroforming mandrel or an electroplating rack, and a current source, comprising: (a) an electrode; (b) a member, spaced apart from the electrode, wherein the member defines a space that is partially or fully filled with a first conductive liquid in electrical contact with the member; (c) a second conductive liquid electrically isolated from the electrode; and (d) connecting means for electrically connecting the first conductive liquid and the second conductive liquid.

Abstract: An apparatus is disclosed for depositing metal on a mandrel which provides a brushless electrical current continuity between the mandrel and a current source, comprising: (a) a metal deposition vessel; (b) an electrode disposed in the vessel; (c) a mandrel disposed in the vessel, spaced apart from the electrode; (d) an electrically conductive liquid disposed in the vessel; (e) an electrolytic solution disposed in the tank; (f) a layer of a substantially electrically nonconductive material disposed between the electrolytic solution and the conductive liquid; and (g) connecting means for electrically connecting the mandrel and the conductive liquid, coupled to the mandrel.

Abstract: An improved thermal ink jet printhead is formed by the alignment and bonding of an anisotropically etched silicon wafer channel plate, containing a plurality of channel grooves, to a silicon wafer heater plate, containing a plurality of heating and addressing elements which are covered by a patterned thick film layer. The printhead enables better bonding of the two plates by compensating for raised lips or edges formed on the outside edge of opposing last pits in an array of pits located in the thick film layer that are created while photofabricating the pits in the insulating layer. The fabrication sequence compensates for the raised edges by including a non-functional straddling channel that nullifies the standoff created by the raised edge and a corresponding additional non-functional pit that positions the raised edge away from the functional channels and nozzles.

Abstract: A method of dicing a printhead wafer containing a plurality of individual print elements into discreet elements. A back side relief feature is formed on the bottom front edge of a thermal ink jet print element from a heater side during a first dicing cut, followed by a second dicing cut from a channel side of the wafer to form a front face nozzle. The back cut feature enables front face maintenance by a wiper blade or other maintenance operation, provides a pocket for excess die bonding adhesive during manufacture, and reduces front face chipping during dicing caused by the saw blade contacting the die wafer mounting media and becoming contaminated. The relief feature may be a square step feature or a beveled back cut feature and may additionally be located on a top front edge of the print element.

Abstract: A plurality of ink jet printheads are produced from two aligned and bonded substrates by an improved fabrication method. The confronting surface of one of the substrates contains a plurality of linear arrays of heating elements and driver circuitry, and the confronting surface of the other substrate contains a plurality of sets of shallow channel recesses, reservoir recesses, and alignment openings. Prior to mating of the substrates, the substrate surface having the channel recesses is coated with a layer of thermosetting adhesive, and a thick film layer is deposited on the substrate surface having the heating elements and driver circuitry and patterned to provide a plurality of vias therein at predetermined locations. The vias expose the heating elements, provide ink bypass trenches, and provide a number of groupings of small pits.

Abstract: Disclosed is an apparatus for degassing a liquid, comprising: a liquid supply and an outlet communicating with the liquid supply via a flow path; a degassing tank, disposed in the flow path between the liquid supply and the outlet, the degassing tank incorporating a gas-permeable vent; a means for moving the liquid along the flow path; and a heater, disposed in the flow path between the degassing tank and the outlet, for heating the liquid and thereby removing gas therefrom. The apparatus is particularly suited to the ink supply system of a thermal ink jet printer where the removal of gases dissolved in the ink improves print quality.

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 of fabricating thermal ink jet printheads comprises aligning and bonding a pair of silicon wafers together, which have, on opposing confronting surface thereof, a plurality of sets of linear arrays of heating elements and associated driver circuitry on one wafer surface and a plurality of sets of parallel grooves and a communicating reservoir for each set of grooves. The grooves and reservoirs are filled with a filler material which is solid or gels at room temperature and liquid at higher temperatures. The bonded pair of wafers are severed into a plurality of individual printhead sby dicing processes conducted at room temperature. One of the dicing processes cuts the grooves in a direction perpendicular thereto in order to form concurrently the nozzle face and nozzles. The solid filler material supports fragile edges of the wafers and prevents entry of dicing debris and other contaminants. The printheads are subjected to heat, spinning, and high pressure water spray to remove the filler material.

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: 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 corona generating device for depositing negative charge on an imaging surface carried on conductive substrate comprises at least one elongated conductive corona discharge electrode, means to connect the electrode to a corona generating potential source, at least one element adjacent the corona discharge electrode capable of adsorbing nitrogen oxide species generated once the corona generating electrode is energized and capable of desorbing nitrogen oxide species once that electrode is not energized, the element being plated with a substantially continuous thin layer of lead to neutralize the nitrogen oxide species when generated.