Fabric, in particular for an airbag

Abstract

A fabric is described, in particular for an airbag, consisting at least partially of hollow filament yarns (K, S) made of a polymer material, wherein the fabric has a cover factor DG, according to Professor Walz, that is equal to the cover factor when using solid filament yarns of the same diameter.

1 . A woven fabric, especially for an airbag, comprising, at least in part, hollow filament yarns of a polymer material, wherein said woven fabric features a cover factor with a WALZ density equalling the cover factor when employing solid filament yarns the same in diameter. 
     
     
         2 . The woven fabric as set forth in  claim 1 , wherein said hollow filament yarns have a smaller denier than solid filament yarns the same in diameter and made with the same polymer. 
     
     
         3 . The woven fabric as set forth in  claim 1 , wherein the weight of said woven fabric employing hollow filaments is lower in the scope of the lumen percentage as compared to solid filaments. 
     
     
         4 . The woven fabric as set forth in  claim 1 , wherein said weave is structured as L1/1 or in a higher weave. 
     
     
         5 . The woven fabric as set forth in  claim 4 , further comprising solid filament yarns the same in diameter and made of the same polymer, wherein the hollow filament yarns are arranged at predefined locations of a repeat in the warp and/or weft and are interwoven in a weave structure higher than L1/1 and with a higher thread density than that of a L1/1 weave structure. 
     
     
         6 . The woven fabric as set forth in  claim 4 , further comprising solid filament yarns the same in diameter and made of the same polymer and that, wherein the hollow threads are incorporated in stitched weft technology in zones particularly exposed to thermal stress in an OPW airbag and are interwoven in a weave structure higher than L1/1 and with a higher thread density than that of a L1/1 weave structure. 
     
     
         7 . The woven fabric as set forth in  claim 1 , wherein said percentage of the hollow surface area or lumen percentage of the hollow filament yarns is in the region of 20% or higher. 
     
     
         8 . The woven fabric as set forth in  claim 1 , wherein said cover factor has a WALZ density greater than 100%. 
     
     
         9 . The woven fabric as set forth in  claim 8 , wherein said cover factor has a WALZ density greater than 105%. 
     
     
         10 . The woven fabric as set forth in  claim 1 , wherein said hollow filament yarns and solid filament yarns are polyester yarns. 
     
     
         11 . The woven fabric as set forth in  claim 1 , wherein said polymer material is polyester and wherein:
 a) the yarn diameter,   b) the number of threads per cm,   c) the WALZ density cover factor DG,   d) the thickness of the woven fabric, and   e) the weight of the woven fabric correspond to that of a fabric woven from polyamide 6.6 solid filaments.   
     
     
         12 . The woven fabric as set forth in  claim 1 , wherein said woven fabric features a uniform edge comb resistance. 
     
     
         13 . The woven fabric as set forth in  claim 1 , wherein a thread density (number of threads per cm) of the woven fabric is the same or higher as when employing solid filaments with the same diameter and with the same woven structure. 
     
     
         14 . The woven fabric as set forth in  claim 1 , wherein a woven thickness is the same or higher as when employing solid filaments with the same diameter and with the same woven structure. 
     
     
         15 . The woven fabric as set forth in  claim 1 , wherein the fabric is woven as an OPW incorporating single-ply and two-ply zones, wherein the fabric further comprises substantially elongated tubular structures or tubes running in the warp or weft direction, said single-ply zones containing hollow filaments. 
     
     
         16 . The woven fabric as set forth in  claim 15 , wherein said thread system running transversely to the tubes incorporates either solid filaments or hollow filaments. 
     
     
         17 . The woven fabric as set forth in  claim 15 , wherein said thread system running transversely to the tubes is configured in an alternating thread sequence. 
     
     
         18 . The woven fabric as set forth in  claim 15 , wherein said elongated tubular structures or tubes running in the warp and weft direction are configured as hollow filaments and the single-ply zones are formed of solid filaments especially in the direction of particular tensile stress.