Sound absorbing material

Abstract

The invention relates to a sound absorbing material, made from a microfilament nonwoven fabric having a mass per unit area of 40 to 300 g/m 2 , in which a nonwoven fabric is made from melt-spun, drawn, multi-component endless filament having a titer of 1.5 to 5 dtex and directly laid down to form a fibrous web; and the multi-component endless filaments, optionally after prebonding, are split at least to 80% to form micro-endless filaments having a titer of 0.1 to 1.2 dtex and bonded.

What is claimed is:  
     
         1 . A sound absorbing material made from a microfilament nonwoven fabric having masses per unit area of 40 to 300 g/m 2 , the nonwoven fabric being made from melt-spun, drawn, multi-component endless filament having a titer of 1.5 to 5 dtex and directly laid down to form a fibrous web; and the multi-component endless filaments, optionally after prebonding, are split at least to 80% to form micro-endless filaments having a titer of 0.1 to 1.2 dtex and bonded.  
     
     
         2 . The sound absorbing material as recited in  claim 1 , 
 wherein the nonwoven fabric is made from melt-spun, aerodynamically stretched multi-component endless filaments directly laid up to form a web, having a titer of 1.5 to 3 dtex, and the multi-component endless filaments, optionally after prebonding, are split at least to 80% to form micro-endless filaments having a titer of 0.1 to 0.3 dtex, and bonded.    
     
     
         3 . The sound absorbing material as recited in  claim 1  or  2 , 
 wherein the multi-component endless filament is a bicomponent endless filament made from two incompatible polymers, particularly a polyester and a polyamide.  
 
     
     
         4 . The sound absorbing material as recited in one of  claims 1  to  3 , 
 wherein the multi-component endless filaments have a cross-section having an orange-like multi-segment structure, whereby the segments alternately contain one of the two incompatible polymers, in each instance, and/or have a “side-by-side” structure.  
 
     
     
         5 . The sound absorbing material as recited in one of  claims 1  to  4 , 
 wherein at least one of the incompatible polymers forming the multi-component endless filament contains an additive, such as color pigments, permanently acting anti-statics, flame retarding agents and/or additives that influence the hydrophobic properties, in amounts up to 10 percent by weight.  
 
     
     
         6 . A method for the production of the sound absorbing material according to one of  claims 1  to  5 , 
 wherein multi-component endless filaments are spun from the melt, stretched, and directly laid up to form a web, that prebonding takes place, if necessary, and that the nonwoven fabric is bonded using high-pressure fluid jets, and, at the same time, split into micro-endless filaments having a titer of 0.1 to 1.2 dtex.  
 
     
     
         7 . The method as recited in  claim 6 , 
 wherein the multi-component endless filaments are bonded and split in that the nonwoven fabric, which has been prebonded if necessary, is impacted at least once on each side with high-pressure water jets.    
     
     
         8 . The method as recited in  claim 6  or  7 , 
 wherein the multi-component endless filaments are dyed by spin-dyeing and/or overdyeing.  
 
     
     
         9 . The method as recited in one of  claims 6  to  8 , 
 wherein the sound absorbing material is spot-calandered.  
 
     
     
         10 . The sound absorbing material as recited in one of  claims 1  to  9 , 
 wherein it is used for the production of car roof linings, door paneling, column paneling, rear window shelves and/or trunk paneling, as well as wheel box paneling.  
 
     
     
         11 . The sound absorbing material as recited in one of  claims 1  to  9 , 
 wherein it is used as a sound absorbing layer in the construction of roof linings, in the construction of column, door, and trunk linings, in the construction of dashboards, in the area of the engine compartment and/or floor linings.  
 
     
     
         12 . The sound absorbing material as recited in one of  claims 1  to  9 , 
 wherein it is used as a tuft carrier for automobile carpeting.