Primary carpet backing

Abstract

A primary carpet backing comprising at least a first and a second layer of fibers, characterised in that both the first and the second layer of fibers is a nonwoven layer of randomly laid fibers, that both the first layer of fibers and the second layer of fibers has a uniform composition throughout the layer, wherein the linear density of the fibers is in the range of 1 to 25 dtex, wherein both the first layer of fibers and second layer comprises at least two different polymers and wherein at least one polymer comprised in the first layer is different from the polymers comprised in the second layer.

What is claimed is: 
     
         1 . A primary carpet backing comprising at least a first layer of fibers, a second layer of fibers, and a third layer of fibers wherein:
 the first layer of fibers, the second layer of fibers, and the third layer of fibers are a nonwoven layer of randomly laid fibers,   a linear density of the fibers is in a range of 1 to 25 dtex,   the first layer of fibers, the second layer of fibers, and the third layer of fibers have uniform composition throughout each layer of fibers,   the first layer of fibers, the second layer of fibers, and the third layer of fibers consist of two different polymers,   the first layer of fibers, the second layer of fibers, and the third layer of fibers comprise polyester as a backbone polymer,   at least one of the polymers in the first layer of fibers is different from one of the polymers in the second layer of fibers,   the different polymers in each layer of fibers exist in bicomponent fibers,   the bicomponent fibers in the first and third layer of fibers comprise a polyester core and a polyamide sheath, and   the bicomponent fibers in the second layer of fibers comprise a polyester core and a polyolefin sheath.   
     
     
         2 . The primary carpet backing according to  claim 1 , wherein the primary carpet backing is thermally bonded with a binder polymer originating from the fibers. 
     
     
         3 . The primary carpet backing according to  claim 1 , wherein the primary carpet backing comprises one or more additional layers, each of the additional layers being selected from the group consisting of woven layers, nonwoven layers, scrim layers, layers of unidirectional filaments or yarns, and film layers. 
     
     
         4 . A tufted carpet comprising the primary carpet backing according to  claim 1 . 
     
     
         5 . The primary carpet hacking according to  claim 1 , wherein the different polymers in the first layer of fibers or the second layer of fibers have different melting points.