EasyReliablePeel

Throughout the last years peelable films have been designed, in order to provide the technical conditions for launching easy-to-open packaging concepts. This type of packaging is currently increasingly required by consumers and the packaging industry. Not only because of the demographic change, have consumers wanted the packaging industry to bring easy to open packages into the market. The amount of peelable packaging is not only increasing in the field of consumer packaging but furthermore they enable easy handling of medicine products in sterile working environments and reduce the risk of contamination.

A prerequisits for the application of peelable packaging is a safely working peel-system which avoids crack patterns like angel hair and tearing of packaging material when the package is opened.

Easy-to-open packages shall meet the requirement for low opening forces regarding the guideline values according to IVLV-Technical-Bulletin 106. But it is most important to keep the products safe during transport, handling and storage. To meet both requirements, product safety and easy opening, low opening forces together with a small scattering of the force values have to be realized. This leads to the demands for highly reliable sealing processes and properties of the packaging material.

Aim of the project is the development of a tool for calculating opening forces on peelable packages. Furthermore, influencing parameters on the peel behavior of packages like the film structure, the position and the direction of the tear force application will be described for adhesive and cohesive-peel-systems. This will be investigated by:

• Describing the crack initiation and propagation in the sealed seam during the tear process, depending on film structure (support and peel layer) and the sealing parameters (formation of the sealed seam),
• Working out the structure-property-correlation (relations between polymer structure, mechanism of adhesion and the resulting crack initiation and propagation processes) on the basis of investigation and analyzing of polymer structure and peel tests
• Describing of geometric conditions during the peel process on packages (length of the peel line, direction of opening) compared to the peel process on test strips
• Describing of influencing parameters to avoid unwanted crack patterns

The determined influencing parameters will be verified with a simple calculation tool. This tool serves to calculate the opening force on the basis of the sealed seam contour and the properties of the packaging material. After finalization of the research project the calculation tool will be available for the implementation of bilateral projects. The project results will be described easy understandably, accompanied by advice for the packaging industry and be provided as IVLV-Technical Bulletin.