| 摘要 |
PROBLEM TO BE SOLVED: To provide an acoustic material having a suppressed weight increase, excellent in acoustic performance and vibration-damping property in a medium- to-high frequency region and suitable as an acoustic material for automobiles or the like by laminating a specific composite nonwoven fabric. SOLUTION: This acoustic material is obtained by laminating a composite nonwoven fabric constituted of fibers of <=1.0 denier obtained by a melt blow method and having a surface density of 20-100 g/m2 in which short fibers are dispersed and mixed at a ratio of 20-100 g per 1 m2 on one side of a short-fiber nonwoven fabric constituted of short fibers such as polypropylene fibers of 1.0-10 deniers and having a surface density of 100-1,000 g/m2. Further, it is preferable that the mixed short fibers are polyethylene terephthalate short fibers of 0.5-15 deniers in fineness, and the short-fiber nonwoven fabric has a surface density of 100-1,000 g/m2, an air permeability of 15-100 cm3/min and a spring constant k of 5-50 kg/cm when determined from the compressive load of 50% compression.
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