PREPRESS
The procedure is based on a volume-oriented , three-dimensional measurement that compensates for geometrical distortions and the stylus wear of the engraving diamond .
z Laser engraving
The gold standard of high-resolution cylinder engraving is direct laser engraving . 4Packaging has been manufacturing laser-engraved gravure cylinders for 13 years and currently has three Cellaxy direct lasers . These are used for embossing and high-resolution linework and half-tone reproductions . A large share of the orders are for cigarette packaging , but other forms of high-quality packaging are also becoming increasingly popular . Recently , 4Packaging successfully matched the printing characteristics of conventionally engraved cylinders and laser-engraved cylinders . In this way , it standardized its laser engraving process . Now printers can run either individual cylinders from the color set or a complete color set with laser-engraved cylinders without any additional fingerprinting . Another advantage for printers , according to 4Packaging , is the significant ink saving that the laser-engraved cylinder offers compared to conventional engraving . The fully automated line installed at 4Packaging for the premium preparation of laser-engraved cylinders is unique and creates the basis for perfect reproducibility .
z Detail reproduction
“ Engraving systems adjusted with MultiTune produce a higher contour definition and reduce undesirable engraving effects such as dragging or ringing ” Photo Hell Gravure Systems
Fine lines and text are always a challenge in gravure printing . This is not just because of the above-mentioned problem with edge sharpness . Another issue in gravure printing is that fine elements are normally reproduced more thinly than in the original . This applies equally to positive and negative elements . Repro data normally has to be corrected manually in line with specific engraving requirements to correct this effect . Manual correction takes a lot of time and it is very easy to make mistakes . In addition , ma- king very fine text thicker can cause open elements to close up or individual letters to run into each other . In both cases , this can make text much more difficult to read .
High Quality Hinting Pro ( HQH Pro ) provides 4Packaging with a process that automatically optimizes engraving data . This process has no impact at all on the engraving machine ’ s speed or productivity .
z Quality assurance
The aim of quality assurance is to deliver consistently high quality to customers . This involves identifying tolerances that cannot be allowed in cylinder production as early as possible in order to prevent costly remakes . Certified Engraving processes measure and record critical cylinder production parameters directly on the output device . This means tolerances in cylinder production and cylinder engraving that cannot be allowed are spotted quickly . For example , Certified Engraving measures cylinder engraving at pre-defined locations and visualizes larger engraved areas with the help of a stitching function . This detects slipping on the cylinder and any height difference between the engraving styluses in multichannel operation . All measured values and camera images are documented in a customer-specific engraving certificate . All in all , Certified Engraving makes the entire cylinder manufacturing process more-reliable and also reduces the need for proof printing . The software is installed on all 4Packaging engraving systems . The quality data obtained is stored centrally at first and is then incorporated into the cylinder certificate at 4Packaging ’ s in-house quality station . z
5 October 2021 Packaging South Asia
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