PETpla.net Insider 01+02 / 2018

PET planet Insider Vol. 19 No. 01+02/18 www.petpla.net 41 TRADE SHOW REVIEW filling plants of the beverage and food industries. While Krones at the last Drinktec exhibited a prototype of the DecoType family, meanwhile the digital direct printing machine has attained product maturity. The DecoType Select prints on both special-shaped and cylindrical containers made of PET, HDPE and glass; capabilities for handling metal containers and other plastics like PP are currently under preparation. In contrast to traditional labels, moreover, direct printing can also be applied selectively to grooved and relief structures. This opens up new opportunities for consumer products, to differentiate them distinctively from the mass of competing articles – e.g. by creating 3D effects on their packaging or simulating the look of different materials. At the same time, the print height of up to 205mm still leaves sufficient space for accommo- dating not only elaborate designs, but also detailed textual information on the packaging. In conjunction with external partners, Krones has created an ink composition for PET that has been confirmed as recyclable in labora- tory tests and also meets the hygiene standards of the packaging industry. When it came to the colour space, the R&D people at Krones opted for the established CMYK model which can be extended to the hexachrome model, or alternatively special inks (spot colours) can be used. The asso- ciated printing heads operate using the drop-on-demand principle, where each drop of ink is not created until immediately before it is actually used. An automatic cleaning system for the print heads assures optimal print qual- ity and high machine availability. www.krones.com Form and fill technique Liquiform - an update Dr Christian Compera, Head of Bottling Technology Krones in conversation with Gabriele Kosmehl, PETplanet Insider. PETplanet: Dr Compera, when last we spoke at the Brau Beviale 2016, you mentioned a new milestone in in-house developments in Liquiform technology that was expected to be reached by the time of Drinktec ( see PETplanet 1+2/2017 ). How have your expectations been met thus far? Compera: We took control of the Liquiform technology, assimilated it and have now developed the first pro- totypes which are being used to fully groundtruth the technology and test its robustness. At this stage, it is impor- tant for us to identify potential pitfalls and explore system responses before deciding which direction we should take. Naturally, the risks to customers who acquire the technology will be kept to a minimum. So far, we have not encountered any insurmountable difficulties and overall everything is extremely positive. PETplanet: You were originally thinking of still water in PET or HDPE as the initial application of form-fill technology. Which elements have you been able to successfully road-test so far? Compera: The drinks’ industry is naturally uppermost in our thoughts but it is conceivable that we could explore other lines of business. The form-fill of liquid food and healthcare products as well as water using the Liquiform process is a very feasible option. However, we would need to discuss this with the customer. Decisions will be taken on this over the next few months. Plans for packaging sizes ranging from 250ml to gallons in PET, HDPE or PP for a variety of applications using the Liquiform process at Krones are being made. PETplanet: What is currently getting in the way of using the process in series production? Compera: Our next major challenge is the closure of full bottles. Given that it takes less than 100 milliseconds to form and fill a 0.5l bottle, we natu- rally do not want to limit the advantages brought about by this enormous speed for the capping. We are deriving positive benefits from using our Dynafill system where the one step filling and closure of bottles in a filling carousel only takes a few seconds. The exact dosage in terms of filling capacity is a tricky question. If the stretching rod is pulled in shaping and filling, the displacement volume of the rod for each product needs to be taken into account in order to reach the precise filling level. PETplanet: Mr Compera, many thanks for these new insights!