On 5 April some 300 print providers and buyers from 16 mostly European countries gathered in Radebeul, Germany, for an update on innovations in manufacturing and finishing folding cartons for food and non-food products. Organised jointly by Koenig & Bauer (KBA), Smurfit Kappa Carton and Epple Druckfarben under the banner "Performance is the key", the event focussed on consumables, print production, finishing and logistics.
After welcoming the guests, Wolfgang Suerbaum (Smurfit Kappa Carton), Joachim Erlach (Epple Druckfarben) and Ralf Sammeck (KBA) handed over to Smurfit Kappa Carton sales director Steffen A Rapp, who propounded the virtues of Multiprint and Twin Coat recycled board, describing them as high-performance products. Until now this term has usually applied to board made of virgin fibres, but the two new types of recycled board closely resemble coated chromo board in terms of both print performance and surface qualities. They both have a high degree of whiteness, good opacity, optimum absorbency, a smooth surface and high gloss. Layer integrity during impression is good and there is very little blanket contamination from paper dust, so cleaning intervals are exceptionally long and press capacity can be exploited to the full.
Recycled board: sustainable resource management
Recycled board is a resource-friendly product, being made not only from renewable raw materials, but reusable ones as well. It is also far less energy-intensive to produce than virgin board, and can be used to package all types of products, even foodstuffs. So it is a viable alternative to virgin board.
Antje Kersten, a chemist from Darmstadt University specialising in papermaking and mechanical processing technology, gave a talk on defining, evaluating and reducing the use of mineral oils in food packaging. Research has shown that food packed in cartons may contain traces of mineral oils whose potential negative impact for the consumer is not yet known. Such traces of mineral oil may stem from the inks used to print the cartons, or from recycled board with a high newsprint content. Antje Kersten explained how the presence of mineral oils in the various offset processes depends on the composition of the printing inks used.
Factors influencing the migration of mineral-oil components
At present, problems in analysing mineral oils are partially due to the lack of threshold values for such oils in paper and board, and standardised methods for measuring compounds of mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH). Migration by mineral-oil components from packaging to food depends on various factors, including packaging design, the food packaged, the inner lining, the type of transport and secondary packaging used, and storage time and conditions.
There are several ways to reduce mineral-oil migration from food packaging. One is to substitute virgin board for recycled board, or to use recycled board with a low newsprint content. Another is to dispense with mineral-oil based chemical additives during the papermaking process, ink formulation (manufacture) or application (printing). Barrier coatings and inner bags also provide reliable protection. However, many of the steps that could be taken are not yet feasible in terms of sustainable production.
Printing inks: low odour, low migration or migration-neutral
Matteo Piller, product manager for packaging inks at Epple, gave a briefing on two migration-neutral ink series, BoFood MU and SensPrint MU. He started by detailing the diverse demands on packaging: consumers' priorities are safety and environmental compatibility. Brand manufacturers seek to avoid conflict with consumers, associations and legislators, and also demand safety. Carton manufacturers need to meet customer specifications, comply with ISO standards and maintain a high and stable output.
Today's migration-neutral inks are the product of a multiphase development process that started with low-odour inks (Epple's GA series), which have excellent organoleptic (sensory) and printing properties, do not cause swelling and contain no mineral oils. This makes them suitable for non-food packaging, secondary food packaging, primary packaging with a functional barrier and primary packaging if approved by an independent body. The next step was low-migration inks such as CareFood MAW, which satisfy all legal requirements in Europe and are therefore suitable for direct-contact food packaging. But the ultimate printing inks for food packaging are migration-neutral ones, at present available solely from Epple. The only potentially migratory ingredients in SensPrint MU (optimised for KBA Rapidas) and BoFood MU are foodstuffs or food additives. In the unlikely event that migration occurs it would only be of odour- and taste-neutral components. The same binding agent ensures that the ink penetrates fast and prints well. BoFood MU and SensPrint MU thus comply with all current and foreseeable legal requirements and demands from the food sector.
Safeguarding migrational neutrality
Epple guarantees migration neutrality in ink manufacture by processing optimised, precisely specified raw materials, rigorously vetting all incoming ingredients and implementing special processing regulations. Every batch is tested prior to being filled into containers. Epple also helps customers make the most of a new type of ink by providing professional support with print production, modifying the ink formulation, setting up an ink database and assisting with audits and plant certification.
Performance and cost efficiency in packaging printing were the subject of a talk by Jürgen Veil, KBA head of sheetfed marketing and product management. He focussed on two aspects – cutting makeready times when printing packaging on the popular B1 (41in) Rapida 106, and new features in large-format sheetfed offset. DriveTronic components for this format already include KBA's sidelay-free Sensoric Infeed System, which reduces makeready time by dispensing with setting and marking, and has a tolerance range of ±7mm (0.27in), more than any other pull system. This dramatically reduces the risk of stoppages. And there are no leading-edge errors because the sheets are not pulled sideways and so can no longer tear. DriveTronic SPC accelerates the makeready process by cutting plate-changing time to virtually zero, since it operates simultaneously with other makeready processes. DriveTronic Plate Ident promotes reliability by identifying the plates during the changing sequence, presetting registration and conducting a plausibility check between the plate and the job.
Simultaneous makeready processes boost output and efficiency
KBA's CleanTronic Synchro allows the impression cylinders, blanket cylinders and rollers to be washed simultaneously – and, on presses with SPC, during a plate change. This can deliver a further saving of some 30 per cent. It is also possible to wash the impression and blanket cylinders simultaneously, or the blanket cylinder in half the time with two washing bars, on a large-format press. Valuable time can be saved even when only the blankets need washing.
A complete change of plates on a large-format KBA press takes around two-and-a-half minutes, including resetting register to zero. An automatic change of coating plates on a Rapida is much faster than on comparable make of press. Small details often have a big impact on the effective printing time. For example, a plastic film on the ink-duct cuts cleaning times during ink changes. And a new energy-efficient dryer, VariDryBLUE, reduces heat generation and the volume of exhaust air through heat recovery. This cuts both costs and carbon emissions. Nonstop automatic systems at the feeder and delivery, combined with automated logistics systems for the substrates, make the Rapidas highly efficient, cost-effective packaging presses.
KBA PressConsum: tested consumables from Radebeul
KBA also officially announced its entry into the consumables business. Print chemicals, blankets, inks and many other products for litho presses are now available under the brand name KBA PressConsum. All the products selected have been benchmark-tested and optimised in collaboration with the manufacturers. Some KBA users have already run successful tests in the press room. PressConsum consumables are also used in KBA's customer centre, for press acceptance tests, at trade fairs and for customer training. This means that any quality fluctuations can be detected and remedied in good time. Packaging printers will be interested to know that the range includes Epple's SensPrint MU migration-neutral inks, developed exclusively for KBA.
All medium- and large-format Rapidas for European customers will be shipped with a PressConsum starter kit complete with an order form to ensure a reliable supply. Initially this service will be limited to Germany, Austria and Belgium while KBA establishes the necessary logistics network. Other countries will be added in due course.
Two hours of high-performance packaging production
The theoretical talks were followed by practical demonstrations at KBA's customer centre, where members of the trade witnessed the smooth interaction of the three companies' products. A plinth-mounted Rapida 106 with automated pile logistics printed a commemorative poster on Twin Coat 350gsm GT carton (160lb Bristol). The press was then rapidly converted to print chocolate boxes in four scale colours plus gold, with an aqueous coating. In less than one hour 18,000 sheets were transported at high speed through the press from seven pallets, with the piles at both ends being changed automatically.
The sequence was subsequently repeated on a large-format Rapida 142, which first printed a poster and then applied Euroscale inks, a special green and aqueous coating to frozen food packaging made of Multiprint GD2 400gsm cartonboard (250lb tag). Here, too, nonstop components and a substrate logistics system were in operation. A total of twelve piles with 15,000 sheets apiece were provided for one hour's production. Both presses were run with migration-neutral SensPrint MU packaging inks. The day concluded with a tour of the factory and Dresden's historic city centre, followed by a social evening.