POLYOLEFIN BASED FILMS SUITABLE FOR THERMOFORMING

摘要

The present invention relates to a film structure comprising an outer layer, a core and an inner layer (or sealant layer). The outer layer comprises a polyolefinic material having a Vicat softening temperature of 85°C or greater, most preferable 90°C or greater, and a total crystallinity in the range of 25 to 45%. The core a linear low density polyethylene having a density of 0.925 g/cm3 or less, and a melt index of 4.0 g/10 min or less. The inner layer (or sealant layer), comprises linear low density polyethylene having a density of from 0.865 to 0.926 g/cm3 and a melt index of less than 4.0 g/10 minutes. The films of the present invention are further characterized by having the total amount of polyethylene having a density of 0.930 g/cm3 or greater which makes up the film be less than 25% by weight of the entire film. Further, the films of the present invention can be characterized by the substantial absence (for example less than 5%, more preferably less than 1% by weight of the film) of polyamide, polyester, ethylene vinyl acetate, ionomers, polyvinyl chloride, and/or cyclic olefin polymers.