Metal coated thermoplastics foil waste in lattice form - sepd. into layers by pulling through hot bath and splitting

摘要

Metal coated thermoplastics foil waste in the form of lattices, esp. from the prod. of deep-drawn milk prod. containers, is sepd. into the constituent metal and thermoplastics as follows. The waste strips are pulled through a hot bath, esp. of paraffin and separated by splitting them into thermoplastics and Al (6) by splitting element. The pref. splitting element is a rotatable cage mounted to rotate freely and consisting of a number of freely rotatable roller. More specifically, there are three rollers arranged in an equilateral triangle between two end discs. The spacing between the discs, and therefore the width of the cage is approx. equal to the width of the strip. Used in partic. for the separating of Al foil from PVC, polystyrene or other thermoplastics used in the prodn. of deep-drawn milk prod. containers, esp. quark containers. The heat of the paraffin bath causes the Al to expand but the plastics to shrink, so that they can be easily sepd. By allowing the separating cylinders of rollers to rotate freely according to the pull and separating action, tearing of the somewhat sensitive prod. is prevented and the two sheets peel off easily from each other.