PET bottle becomes PET bottle becomes PET bottle - this is no longer a utopia, but a real possibility. With a new special wash-off adhesive for labels, HERMA makes it possible for very pure PET granulate to be produced during recycling, without annoying residues of paper or film labels or adhesive residues.

Such closed material cycles - instead of the usual downcycling - are one of the most important requirements when it comes to sustainable management. Fo-kus has long since not only included PET beverage bottles but also, for example, bottles for washing up liquid, soap dispensers, and cans for food and cosmetics. HERMA's 62Rpw adhesive is characterised by reliable adhesion and high resistance to moisture. Nevertheless, it can be completely removed again in standard industrial cleaning processes. HERMA's innovative multi-layer technology enables it to combine these contradictory properties. The intermediate layer anchors the adhesive securely to the label material and can therefore be completely removed from the PET surface. The new type of pressure-sensitive adhesive will initially be available with a wet and alkali-resistant paper and a PP film. Certificates from the cyclos-HTP institute have now also been issued for the label materials HERMAcoat greaseproof (grade 228) and HERMA PO transparent (grade 846), certifying recyclability in conjunction with the pressure-sensitive adhesive 62Rpw. For two further label materials made of film - HERMA PP white extra tc (grade 880) and HERMA PP 50 transparent tc (grade 885) - HERMA expects corresponding certificates to be issued shortly. All are materials for use on PET containers. In the HERMA laboratory, these label materials have achieved a wash-off rate of 100 percent with the 62Rpw adhesive, in accordance with the strict specifications of Petcore's "Test Protocol Version 1.4". This is a European association that covers the entire supply chain: from PET manufacturers and PET users to PET recycling companies.
Material cycle largely closed
The recycling of PET containers is particularly interesting for reasons of sustainability: "PET is the only plastic that can also be processed as a post-consumer material into a regranulate by means of an appropriate recycling process that fulfils the legal requirements for a material that comes into contact with food," clarified the Institute for Energy and Environmental Research in Heidelberg (Ifeu) in 2017 in a study commissioned by the German Environmental Protection Agency. Above all, the recycling of PET can take place not just once, but in principle over and over again, the authors of the study emphasize: "Material from a disposable PET bottle for reuse in the bottle (bottle-to-bottle) is very likely (collection rate of 98% in Germany) to be available for further use. From a purely technical point of view, multiple recycling is only limited by the enrichment of additives in the PET. If this material cycle is largely closed, the authors of the study also see a positive life cycle assessment: "Correspondingly optimised disposable PET bottles can achieve a good environmental rating ... However, successful PET recycling can only take place if the input fraction meets certain quality criteria with regard to material purity".
All impurities separated
HERMA's special multilayer adhesive 62Rpw makes recycling PET plastics simple, efficient and therefore cost-effective, as it supports clean and rapid removal of the labels during the washing process. "The fact that the label can simultaneously remove all impurities, especially printing inks, makes it a crucial part of the solution, not only for labelling the containers, but also in the recycling process", emphasises HERMA's Head of Development Dr. Ulli Nägele.
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