Transparent polyester film with high oxygen barrier, its use and process for its production

Abstract

The application discloses a transparent biaxially oriented polyester film having a base layer, at least 80% by weight of which is composed of a thermoplastic polyester, and having at least one outer layer, wherein the outer layer is composed of a polymer or a mixture of polymers which comprises at least 40% by weight of ethylene 2,6-naphthalate units and up to 60% by weight of ethylene terephthalate units and/or of units from aliphatic, including cycloaliphatic, or aromatic diols and/or dicarboxylic acids, with the proviso that the T.sub.g 2 value of the polyester film is above the T.sub.g 2 value of the base layer but below the T.sub.g 2 value of the outer layer, and the base layer comprises particles. The film has low oxygen transmission. It is particularly suitable for packaging applications, specifically for packaging foods and other consumable items, or as a can liner, a lid film or a thermo-transfer ribbon.

Dependencies are inferred from the claim text.