PREPRESS
z Hell rewards outstanding results in cylinder engraving
4Packaging first cylinder engraver to be HD-certified
After implementing Certified Engraving , 4Packaging has become the world ’ s first company to be HDcertified by Hell . This certification recognizes the outstanding results 4Packaging continuously achieves in the four categories of edge sharpness , detail reproduction , reproducibility and quality assurance .
Moving forward , cylinder engravers that achieve outstanding results in printing form production will be HD-certified by Hell Gravure Systems . This certification is based on the four categories – edge sharpness , detail reproductions , reproducibility and quality assurance . A total of seven HelioKlischograph K500 systems and three Cellaxy laser engravers are used at 4Packaging . All of these are equipped with the latest HD software features .
By awarding the HD certification to 4Packaging , Hell is rewarding the company ’ s expert handling of HD technology and stringent quality standards . In an article in Flexo + Tief-Druck 5-2021 , Jan Breiholdt of Hell has explained the processes that are looked at in the Hell HD certification and how 4Packaging has implemented them over more than a dozen years . We excerpt Breiholdt ’ s comments below .
z Edge sharpness using MultiTune
Traditional engraving produces a sawtooth effect . This is because screen ruling and write resolution cannot be set independently of each other . When using the usual screen rulings of 60 or 70 l / cm , gradations are visible to the naked eye – even at a normal viewing distance . Higher screen rulings such as 100 l / cm can be used , but this results in lower printing density and longer engraving times .
4Packaging uses MultiTune on all its electromechanical engraving systems for improved edge sharpness . MultiTune is an adjustment process that produces sharper contours and reduces dragging and ringing . It is particularly effective for horizontal contours and has no impact at all on the machine ’ s engraving speed or productivity .
z Reproducibility
The 4Packaging managers discussed their results during the presentation ceremony at the site in Dissen , Lower Saxony ( Germany ). From left to right : Ralf Reker ( Quality Assurance ), Timo Beck ( Engraving ), Marcel Hartlage ( Laser Engraving ), David Möller ( managing director ) Photo Hell Gravure Systems
Narrow engraving tolerances result in high color fidelity during proof printing and production , and also enable rapid color adjustment in the press . It is therefore vital in electromechanical engraving to calibrate the system before each engraving . This measure – called the ‘ testcut ’ – ensures the current condition of the engraving copper and engraving system has no impact on the engraving result . Using the SprintEasy measuring station , the current condition of the engraving stylus is also taken into account during the testcut .
4Packaging utilizes SprintEasy as a vital quality tool for cylinder engraving and uses the CellEye calibration procedure on the HelioKlischograph systems . Cell- Eye combines measurement using an autofocus camera with an algorithm that automatically aligns the target engraving values and the actual engraving values .
16 Packaging South Asia 5 October 2021