Japan's Oji Paper Co. has developed the industry's thinnest propylene film for the capacitors used in hybrid cars, reports TradingMarkets.com. The new film is only 2.8 microns thick, versus the conventionally used films for the capacitors measure 3 microns. The company has modified the molecular structure of the propylene to enable the film to be stretched thinner. It also uses a certain temperature during the manufacturing process to roughen the film's surface so that it can be wound tightly without slipping.
The thinness of Oji's propylene film allows more material to be wound in the same amount of space, producing a capacitor coil with greater surface area. This results in 15% more charge, a feature that hybrid carmakers can use to boost performance and reduce vehicle weight. Oji occupies in excess of 30% of market share in Japan's propylene films market for hybrid car capacitors and is one of only two Japanese firms (other being Toray Industries Inc.) that make propylene films for hybrid car capacitors in Japan.