Physical Properties of Sprayed Polyurethane Skin for Instrument Panel 2005-01-1217
Physical properties of sprayed polyurethane skin for instrument panel were investigated. Optimized sprayed PU(polyurethane) composition for instrument panel was determined by reaction speed measurement, which were polyol of 6000 molecular weight and modified MDI (NCO=25%). For making sprayed PU skin, raw material was sprayed from 15 cm of distance, at 15 g/min of spraying rate, on 70°C of mold, with 75°C of raw material. Sprayed PU skin had lower density than PVC skin when investigating cross sections of skins using scanning electron microscope (SEM). But the reliability test results satisfied all the specification requirements like scratch, chemical resistance, contamination resistance and fogging. Tensile strength, hardness and elongation of sprayed PU skin were slightly changed during heat aging, but the changing rate was much smaller than those of PVC skin.