Textile gas bag material, a protective cushion for an occupant restraint system and a method for producing the textile gas bag material

Abstract

A textile air bag material for a protective cushion in an occupant restraint system is disclosed. The textile air bag material is composed of a fabric layer having two superimposed wall portions interwoven with each other at their peripheries. The wall portions have a first side with a surface area. On this side a continuous foil of an air-tight material is applied over the entire surface area. Further, a protective cushion made of the textile material and a method for producing the textile material are disclosed.

1 . A textile gas bag material, comprising at least one fabric layer having two superimposed wall portions interwoven with each other at their peripheries, the wall portions having a first side with a surface area on which at least one continuous foil of an air-tight material is applied over the entire surface area.  
     
     
         2 . The textile gas bag material according to  claim 1 , wherein the foil is brought into bond with the wall portions of the fabric layer by a low-viscous substance.  
     
     
         3 . The textile gas bag material according to  claim 2 , wherein the low-viscous substance has thermo-crosslinking properties.  
     
     
         4 . The textile gas bag material according to  claim 1 , wherein the foil and the fabric are based on the same polymeric raw material.  
     
     
         5 . The textile gas bag material according to  claim 4 , wherein the polymeric raw material is a polyamide.  
     
     
         6 . The textile gas bag material according to  claim 1 , wherein the foil and the low-viscous substance are based on the same polymeric raw material.  
     
     
         7 . The textile gas bag material according to  claim 6 , wherein the polymeric raw material is a polyurethane.  
     
     
         8 . The textile gas bag material according to  claim 3 , wherein the thermo-crosslinking substance is a silicone or polyurethane.  
     
     
         9 . The textile gas bag material according to  claim 1 , wherein the foil has a thickness of less than 0.1 mm.  
     
     
         10 . The textile gas bag material according to  claim 1 , wherein the low-viscous substance is applied in a quantity of no more than 50 g/m 2 .  
     
     
         11 . The textile gas bag material according to  claim 1 , wherein the foil is brought into bond with the wall portions of the fabric layer by a thermoplastic substance.  
     
     
         12 . The textile gas bag material according to  claim 11 , wherein the thermoplastic substance is a film having a thermoplastic solidity being at least 15° C. lower than the solidity of the fabric layer.  
     
     
         13 . The textile gas bag material according to  claim 12 , wherein the film is based on a modified polyolefine having a melting point in a range between approximately 85 and 105° C.  
     
     
         14 . The textile gas bag material according to any of  claims 11  to  13 , wherein the foil is based on a modified polyolefine having a temperature stability of at least 120° C.  
     
     
         15 . The textile gas bag material according to  claim 1 , wherein the foil is a polyetherblockamide foil.  
     
     
         16 . The textile gas bag material according to  claim 1 , wherein the foil under the action of heat has a shrinkage of less than 15% in two mutually perpendicular directions.  
     
     
         17 . The textile gas bag material according to  claim 1 , wherein no vent openings are provided.  
     
     
         18 . A protective cushion for an occupant restraint system, comprising a casing, wherein the casing is made of a textile gas bag material according to  claim 1 .  
     
     
         19 . The protective cushion according to  claim 18 , wherein the first side of the wall portions on which the foil of an air-tight material is applied to is the outer side of the protective cushion.  
     
     
         20 . A method for producing a textile gas bag material according to  claim 1  comprising the following steps: 
 interweaving at least two wall portions of a fabric layer at their peripheries; and  
 applying at least one continuous foil of an air-tight material over the entire surface area of the first side of the wall portions.  
 
     
     
         21 . The method according to  claim 20 , wherein the foil is applied by using a low-viscous substance which is introduced at a conventional coating station.  
     
     
         22 . The method according to  claim 21 , wherein the coating station is succeeded by a fixing station where the viscosity of the introduced substance is increased by thermal action.  
     
     
         23 . The method according to  claim 22 , wherein the fixing station is succeeded by a press roller for vertically supplying the foil to the horizontally travelling fabric layer and further by one of a channel and heatable rollers for obtaining a durable crosslinking between the foil, the low-viscous substance and the fabric layer by thermal action.  
     
     
         24 . The method according to  claim 20 , wherein the foil is applied by using a thermoplastic film which is introduced at a conventional lamination calender.  
     
     
         25 . The method according to  claim 24 , wherein the thermoplastic film is introduced between the fabric layer and the foil before the fabric layer and the foil are heated by at least one heatable roller.  
     
     
         26 . The method according to  claim 24 , wherein the foil and the film are produced in a co-extrusion process.