Development of a Light-Weight, High-Dampening, Liquid-Applied Sound Deadener Material

摘要

We have developed a new liquid-applied sound deadener material (LASD) that replaces asphalt-type dampening materials to reduce both automotive weight and the workload of factory associates. Compared to a loss factor of 0.30, this LASD is 62% lighter than conventional materials; compared to an area weight of 2.4 kg/m{sup}2, it displays a 172% higher loss factor. This effect was obtained because the developed liquid-applied sound deadener material uses acrylic resin with a maximum tan δ at 34°C, with the expansion ratio set to 1.8 times. In addition, the viscosity of the liquid-applied sound deadener material was adjusted so the thixotropy would be high at shear speeds of 10 to 3000 S{sup}(-1) to minimize irregularities in the surface when a slit nozzle is used to apply the sound deadener material.