- February 28, 2012
NEU-ISENBURG, GERMANY | Appliance manufacturer Miele is among the first to capture the energy- and waste-saving benefits of a new process and film technology developed collaboratively with a leading machinery manufacturer, film producer, and DuPont Packaging & Industrial Polymers.
DuPont Surlyn, a highly transparent packaging polymer, and specially modified skin packaging equipment form the basis of this new technology designed to protect susceptible, 3-D component surfaces. The process is the result of joint development work between machinery producer, Zappe Verpackungsmaschinen, film producer jura-plast, and DuPont.
Miele uses the technology at its plant in Warendorf, Germany, to prevent high-gloss, thermoplastic bezel for washing machines from becoming scratched as they make their way through the fully automated assembly line to retail and, ultimately, to the end-user's home. The tailored skin packaging process helps prevent rejects and the corresponding raw-material waste.
Reportedly, Surlyn also enables savings in terms of energy and raw material in the skin film process, compared to converting PE, which was the material used in an early development stage. The skin-film itself, and its production residue, can be recycled in the PE waste stream.
"The development of this film has resolved two issues: the special formulation of the base layer made from Surlyn ensures there is no formation of air bubbles between the component surface and the film, which would otherwise spoil the high-quality appearance of the bezel,” says jura-plast managing direct Jürgen Müller. “Moreover, thanks to its combination with a modified adhesive resin from DuPont, adhesion between the component and the film is sufficiently high for the fully assembled washing machine door, weighing around 5 kg, to be transported using vacuum grippers. Yet the consumer is still able to easily peel off the film without leaving any residue behind. [And], as the Surlyn-based film weighs about one-third less than an alternative polyethylene film, we can summarize by saying that we have gained substantial optical, mechanical, and economic benefits with this innovative and sustainable joint development."
Machinery producer Zappe Verpackungsmaschinen highlighted the excellent thermoforming properties of Surlyn. "Thanks to its chemical structure, Surlyn remains very melt-stable and tough even when heated,” says managing director Ulrich Zappe. “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. It was only by switching to Surlyn that we could deliver the high process reliability required by Miele.”
Zappe adds: “Moreover, the good heat absorption of Surlyn makes the film stretchable after only 10 seconds of heating, compared to about 15 seconds required for polyethylene, when working with our SKVA-5050 3D skin-packaging machine. This means we can save a reasonable amount of process energy and on top of that achieve very short cycle times. 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."