HEATSEALABLE MULTI-LAYER POLYMER FILMS

摘要

A multi-layer film comprising: (a) a substrate layer of a thermoplastic polymer film having opposed first and second surfaces; and (b) a heat sealable layer associated with the first surface of the substrate and comprising (i) a first acrylic polymer and (ii) a second polymer which is a copolymer comprising residues derived from one or more olefinically unsaturated monomers and residues derived from one or more olefinically unsaturated monomers which comprise one or more functional groups. The first polymer (i) has a glass transition temperature in the range of from 40 to 120 DEG C and a weight average molecular weight in the range of from 20,000 to 60,000, the second polymer (ii) is a copolymer of a C1-C4 olefinically unsaturated hydrocarbon and an olefinically unsaturated carboxylic acid, and the heat-sealable layer comprises from 5 to 60 % by weight of the first acrylic polymer and from 40 to 95 % by weight of the second polymer.