Although the hybrid vehicle (HV) and electric vehicle (EV) are quieter than the gasoline engine car, the motor built in these two kinds of vehicles decreases the performance as it grows hot, not to mention that the motor will become noisier as it grow big and powerful. A product that absorbs sound and radiates heat for HV and EV will be in great demand. Tokai Rubber developed a urethane foam with sound absorbency and radiation performance for HV and EV. The company bonded thermally conducting materials with magnet, and added the resultant product to a urethane foam. When the final product is put in the mold and foamed in the magnetic field, the thermally conducting materials align. As a result, heat coming from the motor will radiate effectively. The balance between sound absorbency and radiation performance can be adjusted by the additive amount.
The newly developed urethane has high radiation efficiency and reduces the required amount of thermally conducting materials. Accordingly, it will be 40% lighter than silicon rubber to get the same radiation performance, and the production cost will be halved. Tokai Rubber is producing engine covers made of urethane form, and it applied the accumulated knowledge and technology to the development of this new product. It plans to market the new product to automakers and electric appliance makers as a motor cover. It wishes to put into practical use in 2013.