DESCRIZIONE
The present invention relates to a metal layer-free multi-layer film with a surface weight of ≤ 33 g/m2, shrinkage behaviour of ≤ 10% at 90°C (both in the machine direction and transverse to the machine direction, determined as a dimensional change according to DIN 53377) and a layer structure made up of at least six layers comprising a layer (a) composed of at least one thermoplastic olefin homopolymer or copolymer as one of the outer layers, an adhesive layer (b) that is inseparable under a cohesion peeling effect, in other words not peelable, a layer (c) composed of at least one homopolyamide and/or copolyamide, at least one internal gas barrier layer (d) which adjoins layer (c) and differs from layers (c) and (e) at least in the composition of the polymer component(s), a layer (e) adjoining the gas barrier layer (d) and composed of at least one homopolyamide and/or copolyamide, and a layer (i) composed of at least one homopolyamide and/or copolyamide as one of the outer layers. The invention also relates to the use of such a multi-layer film for the production of a buoyancy/lift body and a buoyancy/lift body made of such a multi-layer film.