PETpla.net Insider 08 / 2014

CAPPING / CLOSURES 14 PET planet insider Vol. 15 No. 08/14 www.petpla.net New frontiers Permeation testing on caps *based on an article by Peter Heumueller, Business Friends Market Entry Consultants, Wachtberg, Germany Graham Jennings, Systech Illinois, Thame, UK Recent years have seen tremendous improvements in the oxygen barrier properties of packaging materials. A 1l PET bottle’s barrier properties can be as low as 0,015cm³/b/day. At the same time as packaging is being lightweighted by downgauging, with material content being reduced, barrier properties are being improved in order to extend product shelf life. As packages become more sophisticated, specific area analysis is recom- mended, in order to understand where oxygen permeation occurs. While caps and closures amount to just 0.5 to 6% of the total package, it is worth checking their vulnerability to oxygen ingress. This article offers some ideas and guide- lines for the testing of the oxygen transmission rate of caps and closures. A PET bottle cap has to perform several tasks simultaneously. It must be:  easy to open  tamper proof  tight under all conditions of transport and storage  integrated into the complete package. Oxygen permeation testing is a well-established method of assess- ing barrier properties of films and packages. Systech have performed a number of permeation tests in order to identify the contribution of the closure to the total oxygen transmission of the complete package. Testing regimes should ensure that the closure will be examined and Fig 1. : False-colour photo