PET Foils

In the last years, the use of PET bottle waste has been increased, also for thermoforming foil production.

Various technologies have been confronted in this field, all aimed at avoiding the drying (with the associated high costs) of the flakes before being fed into the extruder.

With the aim of containing plant costs, BG PLAST has developed a single-screw extruder that, thanks to a multiple dosing unit for flakes (virgin and masterbatch) can guarantee the obtainment of a high quality sheet: measuring on the extruded sheet, only a few points of V.I. are losing, compared to the initial values of the food scraps.

In fact, we know how much the presence of moisture in PET affects the intrinsic viscosity of the product (which must then be thermoformed). This moisture must be compulsorily removed by means of a vacuum system with a special high-performance pump.

For food packaging, virgin material in contact with foodstuffs is required. Therefore, the central extruder, flakes fed, is complemented by a co-extruder, fed with virgin material.

This solution makes it possible to produce a multilayer A-B-A sheet with the following percentages: 5-90-5%.

The presence of a silicone bath, along the extrusion line, is the only detail that differentiates this downstream from a normal PP or PS foil line.

In order to be competitive on all fronts, BG PLAST has signed commercial agreements with a major European manufacturer of corotating twin-screw extruders.