In the past, exterior body components in plastics had to undergo elaborate painting. Coloured parts are only employed in a few exceptional cases at present – such as on the "smart". Now a new system, "Paintless Film Moulding" (PFM), has become available by way of an alternative. The four companies of BASF (D-67056 Ludwigshafen), Engel (A-4311 Schwertberg), Röhm (D-64293 Darmstadt) and Senoplast (A-5721 Piesendorf) have cooperated closely on the development of an overall concept for the production of exterior body components in plastic. Instead of the parts being painted, PFM makes use of a completely new in-mould-decoration film, which not only offers technical advantages but also permits an attractive price-to-performance ratio.

The process developed jointly by these companies involves a new film concept in which a carrier layer of ASA or ASA/PC is coextruded with an outer layer of scratch and weather-resistant PMMA. After the film has been thermoformed, PBT/PC, ASA/PC or BAS is injected in behind it on a specially developed injection moulding machine. The PMF technology replaces the conventional painting operation for plastics mouldings, where the polymer/paint combination has to be optimised at great expense for each individual application. According to a company announcement, "the key parameters of a composite produced with PFM technology are a high surface quality, brilliance, toughness and favourable long-term behaviour". A further advantage of this system is its consistent integration of the material concept and the process chain. For the very first time, the automotive industry now has a self-contained and efficient system solution for the production of moulded parts.

Development of the "Paintless Film Moulding" technique was made possible through the comprehensive production know-how of the partners involved: BASF as the supplier of raw materials for film and moulding compounds, Engel as a producer of injection moulds and handling systems, Rohm as a producer of raw materials for film outer layers, and Senoplast as the partner with responsibility for film extrusion and coloristics.

The PFM system will be a key topic in the presentations of the participating companies at K '98 in Düsseldorf (22 to 29 October). Engel will be demonstrating the process in operation on its stand.

READER SERVICE: Press conference speech (English) by Dr. Reinhard Jakobi (BASF) on exterior body components (with further details of the PFM technology): PIE-No. 43031.