Abstract: Several improvements have been made in inkjet print cartridges to realize 5 ng drop weights at ejection frequencies of 18 KHz. These improvements include small nozzle openings, improved heater resistor efficiency, and better ink supply reliability.

Abstract: A fluid ejection device includes a substrate, drop generators formed on the substrate at a high density, primitive select lines, and a ground line. The drop generators are arranged in primitives of drop generators. Each drop generator includes a heater resistor having a high resistance. Each primitive select line is separately electrically coupled to a corresponding one of the primitives and is configured to connect to a power source. The ground line is electrically coupled to all of the primitives.

Abstract: A method of manufacturing an ink jet print head with a substrate defining an ink aperture. A number of ink energizing elements are located on the major surface of the substrate. A barrier layer is connected to the upper surface, and peripherally encloses an ink manifold. The barrier encompasses the ink aperture. An orifice plate is connected to the barrier layer, spaced apart from the substrate's major surface, enclosing the ink manifold. The plate defines a number of orifices, each associated with a respective ink energizing element. The ink manifold is an elongated chamber having opposed ends defined by end wall portions of the barrier layer. The barrier end wall portions each have an intermediate end wall portion protruding into the manifold.

Abstract: An inkjet printing device employs an inkjet printhead with a plurality of drop generators to eject drops of ink. Each drop generator includes a planar heater resistor, a protection layer having a first heating surface on the heater resistor and a second heating surface entirely surrounding the first heater surface on the heater resistor, and an ink ejection nozzle. The drop generator vaporizes ink at the first heating surface and ejects a drop of ink of a first mass from the nozzle when a first range of energies is applied to the heater resistor. The drop generator vaporizes ink at the first heating surface and the second heating surface and ejects a drop of ink of a second mass from the nozzle when a second range of energies is applied to the heater resistor.

Abstract: Several improvements have been made in inkjet print cartridges to realize 5 ng drop weights at ejection frequencies of 18 KHz. These improvements include small nozzle openings, improved heater resistor efficiency, and better ink supply reliability.

Abstract: This present invention is embodied in a low-cost printing system including a printhead and an ink composition that provides photographic-quality resolution. The printhead of the present invention includes a high-density array of drop generators that eject ink drops having a low drop weight and that operate at a high frequency. Further, high-resistance firing resistors are used to provide minimum energy dissipation and the firing resistors are preferably thin-film resistors to ensure that a minimal amount of energy is needed to eject ink drops. The stability of the ink drop volume is maintained by including an overdamped structure within the ink drop generators that allow the ink chambers to fill up with ink slowly. The ink composition of the present invention includes an ink additive that prevents decel from occurring during sustained high-frequency printing bursts.

Abstract: A high quality inkjet printhead includes a substrate having a multiplicity of heater resistors formed thereon at a density of at least six heater resistors per square millimeter. Each of the heater resistors also has a total resistance of at least 70 &OHgr; and an overlaying passivation thermal barrier characteristic adjusted to enable ejection of an ink drop of less than 6.5 ng with an energy impulse equal to or less than 1.4 &mgr;joules.

Abstract: This present invention is embodied in a low-cost printing system including a printhead and an ink composition that provides photographic-quality resolution. The printhead of the present invention includes a high-density array of drop generators that eject ink drops having a low drop weight and that operate at a high frequency. Further, high-resistance firing resistors are used to provide minimum energy dissipation and the firing resistors are preferably thin-film resistors to ensure that a minimal amount of energy is needed to eject ink drops. The stability of the ink drop volume is maintained by including an overdamped structure within the ink drop generators that allow the ink chambers to fill up with ink slowly. The ink composition of the present invention includes an ink additive that prevents decel from occurring during sustained high-frequency printing bursts.

Abstract: A printhead having reduced spray includes orifi from which ink is expelled by an ink ejector. The orifi employ an aperture at the outer surface of the orifice plate having an asymmetrical hourglass shape to cause the expelled ink drop to break off at the narrow end of the orifice aperture.

Abstract: This present invention is embodied in a low-cost printing system including a printhead and an ink composition that provides photographic-quality resolution. The printhead of the present invention includes a high-density array of drop generators that eject ink drops having a low drop weight and that operate at a high frequency. Further, high-resistance firing resistors are used to provide minimum energy dissipation and the firing resistors are preferably thin-film resistors to ensure that a minimal amount of energy is needed to eject ink drops. The stability of the ink drop volume is maintained by including an overdamped structure within the ink drop generators that allow the ink chambers to fill up with ink slowly. The ink composition of the present invention includes an ink additive that prevents decel from occurring during sustained high-frequency printing bursts.

Abstract: This present invention is embodied in a low-cost printing system including a printhead and an ink composition that provides photographic-quality resolution. The printhead of the present invention includes a high-density array of drop generators that eject ink drops having a low drop weight and that operate at a high frequency. Further, high-resistance firing resistors are used to provide minimum energy dissipation and the firing resistors are preferably thin-film resistors to ensure that a minimal amount of energy is needed to eject ink drops. The stability of the ink drop volume is maintained by including an overdamped structure within the ink drop generators that allow the ink chambers to fill up with ink slowly. The ink composition of the present invention includes an ink additive that prevents decel from occurring during sustained high-frequency printing bursts.

Abstract: This present invention is embodied in a low-cost printing system including a printhead and an ink composition that provides photographic-quality resolution. The printhead of the present invention includes a high-density array of drop generators that eject ink drops having a low drop weight and that operate at a high frequency. Further, high-resistance firing resistors are used to provide minimum energy dissipation and the firing resistors are preferably thin-film resistors to ensure that a minimal amount of energy is needed to eject ink drops. The stability of the ink drop volume is maintained by including an overdamped structure within the ink drop generators that allow the ink chambers to fill up with ink slowly. The ink composition of the present invention includes an ink additive that prevents decel from occurring during sustained high-frequency printing bursts.

Abstract: An inkjet printing device employs an inkjet printhead with a plurality of drop generators to eject drops of ink. Each drop generator includes a planar heater resistor, a protection layer having a first heating surface on the heater resistor and a second heating surface entirely surrounding the first heater surface on the heater resistor, and an ink ejection nozzle. The drop generator vaporizes ink at the first heating surface and ejects a drop of ink of a first mass from the nozzle when a first range of energies is applied to the heater resistor. The drop generator vaporizes ink at the first heating surface and the second heating surface and ejects a drop of ink of a second mass from the nozzle when a second range of energies is applied to the heater resistor.

Abstract: In accordance with the invention a multi-chamber printhead barrier design that is compensated for differences in ink properties is disclosed. The printhead comprises different groups of firing chambers, each group dedicated to a different ink. The barrier design is configured to a particular ink property such as viscosity, in order to provide similar ink refill characteristic for the different groups of firing chambers.

Abstract: An ink jet print head with a substrate defining an ink aperture. A number of ink energizing elements are located on the major surface of the substrate. A barrier layer is connected to the upper surface, and peripherally encloses an ink manifold. The barrier encompasses the ink aperture. An orifice plate is connected to the barrier layer, spaced apart from the substrate's major surface, enclosing the ink manifold. The plate defines a number of orifices, each associated with a respective ink energizing element. The ink manifold is an elongated chamber having opposed ends defined by end wall portions of the barrier layer. The barrier end wall portions each have an intermediate end wall portion protruding into the manifold.

Abstract: An inkjet printing device employs an inkjet printhead with a plurality of drop generators to eject drops of ink. Each drop generator includes a planar heater resistor, a protection layer having a first heating surface on the heater resistor and a second heating surface entirely surrounding the first heater surface on the heater resistor, and an ink ejection nozzle. The drop generator vaporizes ink at the first heating surface and ejects a drop of ink of a first mass from the nozzle when a first range of energies is applied to the heater resistor. The drop generator vaporizes ink at the first heating surface and the second heating surface and ejects a drop of ink of a second mass from the nozzle when a second range of energies is applied to the heater resistor.

Abstract: A thermal inkjet printing apparatus employs a segmented heater resistor, a thin passivation layer, and a lower heater resistor activation energy to realize a high density drop generator printhead.

Abstract: An ink jet print head with a substrate defining an ink aperture. A number of ink energizing elements are located on the major surface of the substrate. A barrier layer is connected to the upper surface, and peripherally encloses an ink manifold. The barrier encompasses the ink aperture. An orifice plate is connected to the barrier layer, spaced apart from the substrate's major surface, enclosing the ink manifold. The plate defines a number of orifices, each associated with a respective ink energizing element. The ink manifold is an elongated chamber having opposed ends defined by end wall portions of the barrier layer. The barrier end wall portions each have an intermediate end wall portion protruding into the manifold. Columnar structures placed at predetermined locations, including locations at the end of the ink aperture, and extending from the major surface to the orifice plate control the migration of coalescing bubbles.

Abstract: Ink jet print quality is improved and higher pen speed permitted by a bidirectional printing protocol. According to the new protocol, each individual character to be printed is first partitioned into a leading portion and a trailing portion. The trailing portion includes all trailing edge bits. Only the leading portion is printed on a forward pass of the ink jet pen. The trailing portion is printed on a reverse pass of the pen, so that trailing edge ink drops are instead printed as leading edge ink drops. As a result, satellite ink drops are directed toward the center of the character, where they are covered by primary ink drops, thereby minimizing character edge roughness associated with exposed satellite ink drops.

Abstract: Novel compounds exhibiting liquid crystal properties have the formula:R-.phi.-.phi.-X-.phi.-R1,whereinR and R1 are, independently in each case, hydrogen or an alkyl, aryl, alkylaryl, arylalkyl, or alkoxy group containing from 1 to about 12 carbon atoms, a halogen, a cyano group, an alkyl cyano group of from 1 to 5 carbon atoms, a --CF.sub.3 group, an --N.sub.3 group, a nitro group or a --N(CH.sub.3).sub.2 group, andX is ##STR1## These compounds are especially useful for increasing the clearing point and reducing the operating voltage of liquid crystal compositions including other ester or Schiff base liquid crystal compounds, and the like.