Stork Prints has launched a new generation of its DSI digital label press, with the ability to mount up to ten print stations in line. Andy Thomas reports
Stork Prints’ new generation DSI digital label press comes as standard with four inkjet print stations, but a total of ten positions are available. The company offers a range of possible options for using this number of print heads, including opaque white, variable data printing, extended color gamut, or the possibility of digital varnishing stations.
Label converters who start with the basic configuration can retrofit their DSI press with the extra printing positions at a later date, making it a ‘future proof’ investment.
The DSI press is equipped with a new servo-driven chill drum on the final UV curing station, which will allow more flexibility in the choice of substrates, including unsupported films and thermo-sensitive materials.
Stork Prints also demonstrated to L&L its latest opaque UV inkjet white for applications involving clear films. ‘As we are recognized as the experts in rotary screen printing, we know the specifications and what it means to print a real opaque white,’ says Wilfried Koopman, managing director Graphics at Stork Prints.
Wilfried Koopman sees the fact that Stork Prints manufactures its own ink as a key differentiator. ‘We are not depending on the mainstream ink manufacturers, for whom inkjet is only a very small volume of their market. We are a total solution provider and take full responsibility for the performance and quality’.
The UV ink developed by Stork Prints does not require a protective lacquer for light-fastness or scratch resistance. ‘In our case the UV-flexo lacquer station is not used to protect the print,’ says Wilfried Koopman. ‘It is often used to make the print match the quality of UV-flexo. It can also be used as an individual spot varnish or printing station.’
The Stork Prints UV inks can be changed on the fly, with enough ink stored in the system to keep the press printing. The ink is ‘fixed’ between print stations by individual LED curing units, which stops the ink spreading before it reaches the final (conventional) UV curing station, thus minimizing dot gain. ‘The key to getting the highest quality print out of the DSI digital label printer is to adjust this fixing power depending on the substrate’s effect on ink spreading,’ says Arno Steenkamer, product specialist DSI at Stork Prints. The company has developed a database of different material types with pre-set fixing levels, which also takes account of any corona treatment the material has undergone. ‘The operator is free to fine tune the output of the fixing stations if new materials come along. In general, more pinning supports crisp fine text and reduced pinning contributes to improved flow of the UV inks, and thus optimal solids,’ says Steenkamer.
The DSI is sold by Stork Prints as an in-line ‘hybrid’ press, with modular, integrated finishing – semi-rotary UV flexo station, semi-rotary die cutting, slitting and rewinding. ‘We noticed that there is high interest in an in-line configuration,’ says Wilfried Koopman. ‘Our philosophy is one operator, one machine from start to finish of label production. This approach reduces extra costs of equipment, labor, handling and waste. In this respect, the new DSI offers a superb TCO per printed label.’
The DSI press’ converting section can be switched between full rotary and semi-rotary finishing. The semi-rotary finishing solution is optimal for short runs as only one cylinder size is required to cover all repeats. Printing speed is up to 35 m/min (100ft/min). Koopman stresses that the press can also be sold without finishing solutions where converters want to use their existing equipment.
The DSI can be used to re-register pre-printed rolls, allowing variable black or full color text and images to be added, in register, to a flexo printed roll.
The DSI press comes with its own control system, and one interesting feature is to select only jobs which will be printed on the same substrate. ‘By showing all jobs to be printed on a PE roll, for example, this makes both the workflow and color management system more efficient,’ says Arno Steenkamer. The press software is fully compatible with EskoArtworks’ software systems, making it easy to integrate with wider pre-press workflows. Other standard DSI features include variable data printing (VDP) and non-stop-design-change (NSDC) to support versioning.
Stork Prints is very clear about where the DSI fits into the overall digital print jigsaw. ‘As well as converters moving into digital printing for the first time, we see companies which already own toner systems buying this press as a complementary technology,’ says Erik Blankenstein, area sales manager at the company.
‘The combination of a photographic quality and a rotary screen “look and feel” means that the DSI is very competitive for many label applications, not only for short runs but also medium to long run jobs,’ adds Wilfried Koopman. ‘This will be even more powerful when we bring our new opaque white to the table.’
The new generation DSI press has now been sold and will be demonstrated on the Stork Prints stand at Fespa Digital in Hamburg in May. The press can also be seen in action at Stork Prints’ new digital demo center at its headquarters in Boxmeer, the Netherlands.
In developing the DSI press and its own UV inkjet inks for label printing, Stork Prints has built on knowledge gained from a well-established industrial inkjet printing businesses for both textiles and graphic proofing. The company has, in fact, been active in inkjet printing – with both systems and inks – for more than 20 years, during which time more than 4,000 machines have been installed using its technology. Stork Prints manufactures high-tech electroformed precision components for several well-known inkjet head manufactures, and in the 1990s even manufactured its own continuous flow inkjet heads. ‘In combination with our own manufacturing capabilities for water-based and UV inks, this means that we have the right expertise for optimizing the total system performance for label printing,’ says Wilfried Koopman.
Pictured: UV inks are ‘fixed’ by inter-station LED lamps before final (conventional) UV curing station
This article was published in L&L issue 2, 2011