Abstract:
A single pass inkjet printing method including the steps of: a) providing a radiation curable inkjet ink set containing at least a first and a second radiation curable inkjet ink having a dynamic surface tension of no more than 30 mN/m measured by maximum bubble pressure tensiometry at a surface age of 50 ms and at 25°C; b) jetting a first radiation curable inkjet ink on an ink-jet ink-receiver moving at a printing speed of at least 35 m/min.; c) at least partially curing the first inkjet ink on the ink receiver within the range of 40 to 500 ms after the first inkjet ink landed on the ink receiver; d) jetting a second radiation curable inkjet ink on the at least partially cured first inkjet ink; and e) at least partially curing the second inkjet ink within the range of 40 to 500 ms after the second inkjet ink landed on the first inkjet ink. A single pass inkjet printer is also disclosed.
Abstract:
A radiation curable inkjet printing method for producing printed plastic bags comprising the steps of: a) providing a web-like polymeric substrate having a maximum value for Tan δ between 40°C and 110°C; b) providing a single pass inkjet printer having at least one page-wide printhead or at least one set of staggered printheads, means for transporting the web-like recording medium and curing means; c) jetting onto the web-like polymeric substrate having a surface energy S sub , a non-aqueous radiation curable inkjet liquid having a surface tension S Liq , wherein S Liq is smaller than S Sub by at least 4 mN/m; and d) curing the radiation curable liquid on the substrate at a surface temperature equal or higher than the temperature of the maximum value for Tan δ and smaller than the melting point of the polymeric recording medium
wherein the maximum value for Tan δ is determined by dynamic mechanical analysis at a temperature ramp of 3°C/min using forced oscillation with a cycle of 1 second and an amplitude of 100 µm. A single pass inkjet printer is also disclosed.
Abstract:
A method and an inkjet printing device (10) are disclosed for single pass printing on an ink-receiver (50) having a surface (51), the device including a plurality of sets of nozzles (15-18, 25-28) for jetting N inks on the surface (51), wherein N is larger than or equal to one, the N inks including a first ink, and wherein the plurality of sets of nozzles includes a first (15) and a second (25) set of nozzles for jetting the first ink; the device further including means for radiation curing (19, 41-43) the first ink when jetted on the surface by the first set of nozzles, wherein the means for radiation curing (19, 41-43) is positioned between the first set of nozzles (15) and the second set of nozzles (25).
Abstract:
An ink supply system for an industrial inkjet printer is provided making use of a least one buffer vessel (8) wherein ink at low pressure is isolated and pressurized to a high pressure suited for feeding the ink to the printhead (1). A recirculation ink supply system using plural buffer vessels is suited for repressurizing the ink without the use of a pump. The system avoids generation of gas bubbles due to cavitation which are present in systems using a pump for repressurizing ink.