| 摘要 |
<p>Monolithic acoustical panels are provided including relatively coarse particles of expanded volcanic glass, such as perlite, and mineral fiber. The panel provides a highly porous structure that possesses desirable noise suppression characteristics, and comprises by weight 45 to 75% of an expanded volcanic glass of which 65-100% will pass an 8 mesh U.S. Standard screen and will be retained on a 50 mesh U.S. Standard screen; 10 to 30% of mineral fiber; 10 to 20% of nongelatinous cellulosic fiber having lengths in the range of about 0.5 to 3.5 mm.; and a total of 10 to 25% of binder and sizing agent.</p> |
