Developments to Watch
PLASTIC AUTO PARTS THAT WON'T NEED A PRIMER COAT
Increased use of plastics for bumpers, fenders, and other body panels has helped auto makers reduce weight and increase gas mileage. But the "electrostatic" painting systems they use require that painted surfaces be electrically grounded. So, plastic fenders and bumpers must be primed with a conductive paint before they can be sprayed with enamels. That priming adds as much as $7 per bumper or fender.
A tiny Cambridge (Mass.) materials company has a way to charge the plastics without lessening their smoothness and resiliency, as other conductive additives do. It makes tiny carbon-based fibers that can be mixed with resin to produce an electrically conductive plastic. The company, Hyperion Catalysis International, has recently geared up to make the graphite fibers in commercial quantities. It figures that the fibers would add just $2 to the cost of each bumper or fender. Hyperion says that Ford, Honda, General Motors, and Renault are evaluating conductive plastics to replace priming.EDITED BY RUTH COXETER