| abstract |
The present invention relates to an acoustical insulation material containing a first layer formed from a nonwoven web having a density of at least 50 kg/m 3 wherein the nonwoven web is formed from thermoplastic [meltblown] fibers having an average fiber diameter of less than about 7 microns; and a second layer of a high loft material. The high loft material of the present invention provides bulk to the first layer and may or may not have sound attenuating properties. Examples of the high loft material include, for example, fiberglass and high loft nonwoven webs. Also disclosed in a method of attenuating sound waves passing from a sound source area to a second area. The method includes positioning an acoustical insulation material containing a first layer formed from a nonwoven web having a density of at least 50 kg/m 3 wherein the nonwoven web is formed from thermoplastic [meltblown] fibers having an average fiber diameter of less than about 7 microns; and a second layer of a high loft material, between the sound source area and the second area. |