MASS-SPRING SOUNDS

摘要

The invention relates to a soundproofing, in particular for use in a motor vehicle.The soundproofing comprises a heavy mass and an acoustic spring layer. Said spring layer comprises frizzy fibers between 3 decitex and 7 decitex and a binder for holding said frizzy fibers together. According to the invention, the soundproofing has the following characteristics: the spring layer further comprises microfibers between 0.1 decitex and 1 decitex, the weight of microfibers in the spring layer is between 25% and 400% of the weight of crimped fibers, and- the weight of the microfibers and the weight of the frizzy fibers together represent at least 35% of the weight of the spring layer. / P