| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide lightweight sound-absorbing material with superior sound-absorbing performance. <P>SOLUTION: Paper (3) is composed of pulp fibers with beating degree, expressed as a Schopper freeness of 15 to 30° SR specified by a Shopper freeness test method according to JIS P 8121-1995 5, and synthetic resin is coated and/or impregnated and/or mixed, thereby ventilation resistance is adjusted within a range from 0.05 to 3.0 kPa s/m. Sound-absorbing material 1 is constituted such that the paper (3) is inserted in a porous sheet (2), and the sheet (3) is disposed at a depth side of 6/10 to 9/10 of thickness of the porous sheet (2) from a surface in which noise comes, thereby sound-absorbing performance of the porous sheet (2) can be improved. <P>COPYRIGHT: (C)2013,JPO&INPIT |
