Adhesion to Foil – More than Just a One-Sided Story

Aluminium foil is widely accepted as being one of the best barrier materials in flexible packaging, even in the face of many new and up-and-coming high-barrier plastic layer combinations, copolymers, blends or nano-composites. Besides high thermal conductivity, which facilitates enhanced converting and sealing performance, other key criteria that distinguish “converter foil” from competing materials are its outstanding wettability and robust bonding to a wide range of lacquers, adhesives, films and coatings. This presentation aims to provide a fundamental understanding of how adhesion to aluminium foil works from a foil maker’s practical point of view. Adhesion and adhesion failure in different aluminium-plastic laminates during converting and further packaging processing, as well as a result of interaction with packaged goods, are described using everyday cases. The principles and rules for ensuring sufficient and robust adhesion are derived from these typical examples.