Adhesive film
Adhesive foils (from the Latin adhaerere “to stick”, hence also called adhesive foils) are stretch foils that adhere to smooth surfaces without glue . This adhesion is brought about by loose molecular bonds ( van der Waals bonds , cf. also adhesive force ) between the boundary layers of the surfaces of the film and the material on which it rests. In order for these weak forces to have a noticeable effect, the contact area must be as large as possible, which is only possible with really smooth surfaces such as those of glass , porcelain , polished metal and some plastics. It adheres to itself by being wrapped around it several times. The adhesive force of the mostly multilayered films is achieved by adding sticky polymers or migrating sticky, highly viscous polyisobutylene during film production (see extrusion ) to the film surface layer.
Very thin adhesive films made of polyethylene are used as cling films in the food sector. Somewhat thicker foils are used, for example, as transport protection for electronic displays , as identification labels or as advertising stickers in shop windows . They can be removed without leaving any residue and mostly reused.
literature
- Robert Nabenhauer: Packaging dictionary: technical terms and application examples from experts ... BoD - Books on Demand, 2010, ISBN 978-3-03786-000-7 , p. 6 ( limited preview in Google Book search).