Staggered ultra-violet curing systems, structures and processes for inkjet printing

摘要

Enhanced printing systems, structures, and processes provide enhanced pinning of light sensitive inks before curing, such as to avoid artifacts, e.g. between colors, and/or between regions of different color densities. One or more pinning lamps are controlled or otherwise configured to deliver pinning energy over an interval, e.g. over a period of time or over a percentage of completion, to a pinning threshold level, which may be stored and/or determined. In some exemplary embodiments, the pinning energy is increased linearly over an interval. Other exemplary embodiments provide a stepped or staggered increase in applied pinning energy. An additional level of pinning may preferably be provided after pinning and before curing, at an energy level over the first pinning threshold, and below the curing threshold. The enhanced printing systems, structures, and processes reduce and/or eliminate moderate or large transitions of UV light energy, which may otherwise cause image artifacts.

主权项

1. A process for preventing artifacts in a printed image, comprising the steps of:
providing a printing system, wherein the printing system comprises at least one print head for applying light sensitive ink to a substrate, a mechanism for positioning any of the print head or the substrate in relation to each other, at least one pinning lamp, a mechanism for altering the delivered energy of the at least one pinning lamp to at least one portion of the substrate, at least one curing lamp, and at least one processor; applying the light sensitive ink to the substrate with one or more of the print heads; during a first pinning operation, providing pinning energy to the applied ink on the substrate with the at least one pinning lamp to low pin said applied ink, wherein the processor is configured to operate any of the at least one pinning lamp to controllably increase the pinning energy in an increasing linear or stepped manner over an interval to a low pinning threshold level; during a second pinning operation, applying a second level pinning energy to the low pinned applied ink before a curing step, wherein the second level of pining energy is increased in a linear or stepped manner to a high pinning threshold level that is higher than the determined low pinning threshold level, and lower than a curing threshold level; and providing curing energy to the pinned applied ink on the substrate with the curing lamp, to cure the pinned applied ink.