The modified skin packaging process helps prevent product rejects and therefore cuts back on the raw material waste. It also saves material in the skin film application process when compared with converting polyethylene, the material used in an early development stage. Both the skin film and its production residue can be recycled in the polyethylene waste stream.
Because of its chemical structure, Surlyn is melt-stable and tough, even when heated, Ulrich Zappe, managing director of Zappe Verpackungsmaschinen, said in the press release. "This is particularly important for three-dimensional components, as it enables very high draw ratios without the risk of the film tearing at the edges."
The material's good heat absorption makes the film stretchable after only 10 seconds of heating, instead of the 15 seconds required for polyethylene, when working with the company's SKVA-5050 3D skin-packaging machine. This saves process energy and reduces cycle times, Zappe said. "This is particularly important when the machine -- as is the case at the Miele plant in Warendorf -- is an integral part of the overall production process, and is required to fit a specific cycle rate."