GAS-BARRIER FILMS AND SHEETS

摘要

Multi-layer, gas-barrier, either cast or solid-state oriented, heat-shrinkable, annealed or heat-set, films and sheets suitable for packaging applications which comprise a microlayer sequence (a) comprising a number n of identical repeating units (a'), each comprising the sequence A/B/C, wherein A is a layer comprising a major proportion of one or more thermoplastic (co)polyamides, B is either a layer comprising a major proportion of one or more ethylene-vinyl alcohol copolymers or a layer comprising a major proportion of a (co)polyamide characterized by an OTR of less than 100 cm3.25 µm/m2.day.bar at 23 °C and 0% of RH, C is either nil or a layer comprising a major proportion of one or more thermoplastic (co)polyamides, and n stands for an integer of 3 or more, an outer layer (b) comprising one or more polymers selected from polyolefins, modified polyolefins, and thermoplastic (co)polyesters, and a tie layer between the outer layer (b) and the microlayer sequence (a).