Thermoformable foam sheeting for producing open containers

Abstract

The invention relates to a thermoformable sheeting consisting of a foam material or containing at least one layer of a foam material. The inventive sheeting is particularly applicable for thermoforming cups or trays for packaging and/or consuming food stuffs, by drawing or deep drawing the sheeting and expanding the foam material. The foam material of the inventive sheeting consists of a polypropylene blend containing between 50 and 100% of high melt strength polypropylene, has a density of 0.1 to 0.7 g/cm3, preferably between 0.25 and 0.5 g/cm3, and a cell number of from greater than 300 to 3000 cells per mm3, preferably between 800 and 2500 cells per mm3. The inventive sheeting can be drawn with a high drawing ration (e.g. 1.5) and expanded to be formed into containers even with difficult shapes, whereby no drawing problems arise and the containers produced show a homogeneous opaqueness.

Dependencies are inferred from the claim text.