Development and Implementation of TPO Cover Stock for Instrument Panels 980064
The possibility of changes in field life requirements, elimination of PVC in Europe and the push for a totally recyclable instrument panel have been the driving factors in the automotive industry for the replacement of polyvinyl chloride, PVC with thermoplastic olefin, TPO for automotive interiors. Field life requirements for instrument panels for the North American market has risen to 10 years of desert exposure or equivalent sealed box solar exposure. The TPO developed by Delphi is one of only a few materials able to retain its physical properties and color after this harsh exposure. TPO is fully recyclable, it can be ground and re-extruded into sheet form or ground and reused as a part of an all olefin instrument panel, TPO cover stock, polypropylene foam and rigid polypropylene substrate. In addition to the need to meet field life and recycling requirements other key quality characteristics that presented challenges in the development and implementation of TPO included: grain retention and definition, consistent shrink rates, coating appearance, and coating and foam adhesion.