| 摘要 |
A sound insulating structure, for example, formed on an automobile floor panel comprises a cushioning layer interposed between a covering layer e.g. a carpet, a panel e.g. steel and is made of a nonwoven fabric. This nonwoven fabric includes 5-95 wt% of a first fiber and 5-95% of a second fiber, wherein the total amount of the first and second fibers is 100 wt%. This first fiber has a fineness within a range from 1.5 to 40 deniers, a first melting point, and a first portion including polyethylene terephthalate. The second fiber has a fineness within a range from 1.5 to 15 deniers, a core portion, and a sheath portion covering the core portion. A majority of the core portion includes polyethylene terephthalate. The sheath portion includes an elastic copolyester which has a second melting point that is lower than the first melting point and is not higher than 200{C. The sound insulating structure has a high sound-transmission-loss factor within a so-called road-noise frequency range and an adequate cushioning effect and is particularly superior in sound insulation at a normal temperature (15-40{C). |
