Patent ID: 8637414
Filing Date: 2014-01-28
Classification: B32B,D04H,G10K,Y10T

Abstract:
1. An acoustically tuned gradient density padding material comprising a nonwoven material including a first portion having a first density and a second portion surface having a second density increased with respect to the first density, wherein the padding material is adapted to provide acoustical absorption in frequencies from about 750 to 2500 Hz, manufactured according to a process comprising the steps of: passing a single layer web of nonwoven material between upper and lower belts or rolls; applying heat to the web with at least one of the upper and lower belts or rolls and applying pressure to the upper and lower belts or rolls to densify at least one portion of the nonwoven material without completely melting the fibers of the outermost surface of the nonwoven to produce at least one heat and pressure densified portion; wherein the densified portion has a higher density than another portion of the nonwoven material to impart a density gradient to the padding material; wherein the padding material exhibits an acoustic absorption coefficient greater than 50% in the frequency range of 750 Hz to 2500 Hz.