摘要:
A transparency for ink jet printing is enhanced for use as an ink jet recording medium by increasing the hydrophilicity of the coating formed on a transparent substrate. In one embodiment, the coating is subjected to a corona plasma discharge exposure to create changes in oxygen functionality at the coating surface resulting in increases in surface hydrophilicity. In another embodiment, the surface is exposed with UV radiation and ozone exposure for controlled periods of time. In both cases, the surface hydrophilicity is increased by generating highly reactive free radical oxygen (O.sup.-) which results primarily in increases in the oxygen functional groups C.dbd.O and COO.sup.-.
摘要:
A method and apparatus for controlling the volume of ink droplets ejected from printhead nozzles over a larger printhead operating temperature range. Each nucleating electrical pulse applied to the heating elements in the printhead to eject an ink droplet is preceded by a plurality of non-nucleating pre-pulses. Based upon the printhead temperature sensed, a controller selects the pre-pulse width and time width between pre-pulses from a look-up table.
摘要:
The new heater element design has a pit layer which protects the overglaze passivation layer, PSG step region, portions of the Ta layer and dielectric isolation layer and junctions or regions susceptible to the cavitational pressures. Further, the inner walls of the pit layer define the effective heater area and the dopant lines define the actual heater area. In alternative embodiments, the dopant lines define the actual and effective heater areas, and an inner wall and a dopant line define the actual and effective heater areas. Further, when the new heater element designs are incorporated into printheads having full pit channel geometry and open pit channel geometry, the operating lifetime of the printhead is extended because the added protection of the pit layer prevents: 1) passivation damage and cavitational damages of the heater elements; and 2) degradation of heater robustness, hot spot formations and heater failures well into the 109 pulse range. The printhead incorporating the new heater element design can be incorporated into drop-on-demand printing systems of a carriage type or a full width type.
摘要:
A thermal ink jet printer uses a water-based ink containing a second liquid suspended therein which effects rapid bubble growth with lower pulse power levels. The second liquid, such as hexane, acts as a nucleation trigger for the water-based ink. To be effective in ink nucleation control, the homogeneous nucleation temperature of the second liquid suspension must be below the water-based ink's heterogeneous nucleation temperature and the suspended phase must be present in the form of small droplets with a high number density.
摘要:
An ink jet printing system utilizes a heated rotary printing drum for mounting and carrying paper to be printed by one or more thermal ink jet printheads to achieve black or full color printing at high speed. As printing and drying are achieved prior to any transfer of the sheet from the drum, smudging of images is prevented. Such a printing system is capable of producing dried prints that can be immediately stacked and handled without smudging using slow-drying black inks and fast-drying color inks at speeds exceeding 10 pages per minute for color and 20 pages per minute for monochrome black text or images. Hold down of the sheet onto the drum can be achieved using vacuum or electrostatic forces to precisely retain the sheet on the drum until printing and drying are completed. Partial tone printing on multiple passes of the heated drum is provided to eliminate mottle on large solid areas. Heating of the drum can be performed internally or externally.
摘要:
A capping device for an ink-jet printhead having a nozzle opening defined in a surface thereof. A deformable member is urged into engagement with the surface at a predetermined pressure, causing a portion of the deformable member to be deformed into the nozzle opening to seal the nozzle opening of the printhead.
摘要:
A carriage type ink printer having a replenishable ink cartridge and ink jet printhead mounted on the carriage for translation across a printing region of an ink jet printer. The replenishable ink cartridge having means to keep the necessary negative pressure at the printhead by way of a foam-like material contains an ink supply monitoring means which uses a thermistor and constant current circuitry to indicate when it should be resupplied with ink. The printer controller moves the replenishable cartridge to a predetermined side of the printer beyond the printing region and into position to receive ink from a fixed ink supply container. The ink supply monitoring means indicating when the replenishable cartridge is filled in order to prevent over filling the cartridge.
摘要:
A bubble jet printing device is optimized for extended operation by preventing heat buildup within the printhead and ink supply. Several configurations provides for the addition of heat sinks of appropriate dimensions either directly to the printhead or to an electrode board bonded to the printhead. Plated holes through the electrode board increase heat flow away from the printhead. According to another aspect of the invention, the ink supply cartridge has thermally conductive particles dispersed therethrough to effectively increase its capacity to radiate heat away from the printhead.
摘要:
An ink jet printhead is disclosed which has a heater plate containing the heating elements and driving circuitry means monolithographically formed on one surface thereof and the ink flow directing channel structure is formed on the heater plate using a layer of patternable polymeric material which, in one embodiment, is exposed using a mask to define the channel pattern then developed and cured. After curing, the patterned channel structure is polished to provide a smooth coplanar surface and a cover plate with an aperture therein is aligned and bonded to the channel structure to complete the printhead. The aperture serves as both ink inlet and a portion of the ink reservoir. The channels are open at one end and serve as the droplet ejecting nozzles, while the other ends are closed and extend beneath the cover plate aperture to provide a baffled portion of the ink reservoir and prevent cross-talk between the ink channels. In another embodiment, the channels ends opposite the nozzles open into a common recess with the channels walls extending therein to function as baffles and prevent cross-talk.
摘要:
A thermal ink jet printer including a frame, a printhead mounted to the frame for printing ink images onto a heated and supported substrate, and an efficient substrate heating and supporting assembly mounted to the frame. The efficient substrate heating and supporting assembly includes a heating device, and a substrate supporting member having a front surface including a substrate supporting area for supporting substrates of various sizes one at a time and border areas having a polished finish. The efficient substrate heating and supporting assembly also includes a heat absorbing back surface facing the heating device. The heat absorbing back surface includes an increased heat absorbing area located opposite and centered relative to the substrate supporting area on the front surface. The increased heat absorbing area, relative to a rest of the back surface, has a coat of paint thereon for increasing heat absorption thereinto from the heating device, thereby resulting advantageously in relatively nonuniform heat absorption into the back surface, and relatively in more uniform, adequate and efficient substrate heating and drying temperatures on the front surface, when continuously running a most often run size of substrates.