DaimlerChrysler AG engineers say that within 10 years they will have the technology to make all-plastic-body cars decorated with paint film applied in the mold.
The ionomer-based paint film developed in partnership with a team of suppliers can match most existing body colors with the Class A finish and metallic look consumers want. Marry that development with the injection molding research DaimlerChrysler's Liberty technical group has conducted, and the automaker is looking at the potential for a big change in the ways cars are made.
``We're on the 80-yard line,'' said Nippani Rao, senior specialist in exterior plastics for DaimlerChrysler. ``Imagine that if there's a new plant, we put in five or six injection molding machines, we have the film program and we eliminate half a billion dollars of investment for the paint plant.''
DaimlerChrysler, with corporate offices in Auburn Hills, Mich., and Stuttgart, Germany, officially debuted the film program with its development partners - A. Schulman Inc., ExxonMobil Chemical Co., Mayco Plastics Inc. and toolmaker Build-A-Mold Ltd. - during the Society of Plastics Engineers Automotive TPO Global Conference Sept. 30 to Oct. 2 in Dearborn.
The film program went into production briefly for white front fascias on the 2002 Dodge Neon. The 2003 model now is ramping up for production of both front and rear fascias in three colors - white, red and yellow tones - with another seven colors in final approval stage.
The work is more than just a technology exercise. It also represents a major cost savings for the carmaker, shaving more than $20 off the production cost per vehicle, said Michael McMain, senior engineer for small vehicle exterior systems at DaimlerChrysler.
``That definitely got our management's attention,'' he said.
The auto industry has sought alternatives to the expense and environmental hazards of paint for decades. But finding an alternative able to handle large, complex shapes has been difficult. Some film programs have shown promise, but have not won wide acceptance for creating the metallic shades automakers prefer.
The ionomer film system consists of four layers of materials coextruded at Mayco of Sterling Heights, Mich. The top layer is a clear-coat protective finish, followed by a color layer - both created by Schulman. ExxonMobil specialized in the ``tie'' layer, which serves as an adhesive bond between the coating and the final backing layer, produced for the thermoplastic olefin bumper fascia of an extrusion-grade polypropylene.
Mayco thermoforms a preform of the bumper skin, which then is loaded in an injection molding press at DaimlerChrysler's Belvidere, Ill., assembly plant and applied to the TPO bumper in the mold. The selection of the base materials pays off by chemically bonding the various parts of the film and the bumper.
The final part actually outperforms painted TPO bumpers for scratch and mar resistance and adhesion of the color and clear coat, McMain said. It also requires no special tools or techniques for repair.
``This obviously has great potential going forward, not only at DaimlerChrysler, but at other automakers as well,'' said Scott Upham, senior director of global forecasting for J.D. Power and Associates' automotive forecasting group in Troy, Mich.
``It looks like a relatively revolutionary product. A lot of things have looked good at the trade shows or the car shows, but we never saw a finished product,'' he said.
Schulman and ExxonMobil researchers already are looking at alterations needed to use the film in other body panels, such as doors and fenders, which typically use a different resin combination. A part made of a polycarbonate/ABS, for instance, will have a film that chemically matches it.
DaimlerChrysler and its research team have investigated the possibility of film decorating since the late 1980s, said John Horansky, the film's inventor and a DaimlerChrysler engineer. In 2000 it narrowed the search to the ionomer system and selected key development partners.
The group also settled on the Neon's fascia, selecting a difficult shape with curves and deep draws to prove out the concept. The Neon also gave the team access to DaimlerChrysler's in-house molding operation at Belvidere, with a team already accustomed to producing molded-in-color bumpers.
``We can make the hardest part,'' Horansky said. ``And the fascia is a much bigger part, so you see a much bigger benefit.''
But that does not mean the process was smooth. Mayco had to perfect a preform for the skin that would match the final fascia, investing millions of dollars to add new equipment to a shop that was predominantly an injection molder. It spent $650,000 alone with Flow International Corp.'s Flow Robotics Systems on automated trim systems for the bumper skins.
``We operate in a maturing business, injection molding,'' Mayco President Timothy Hoefer said. ``Now we have a way to grow our company in a different direction, with more options available to us. This is an opportunity to really change the dynamics of our company.''