Silicone coating cloth and air bag

Abstract

The present invention provides a silicone coated fabric comprising a base woven fabric that is formed from a synthetic fiber weaving yarn that has a yarn size of from 100 to 270 dtex, and a weaving size expressed by a product calculated by multiplying the yarn size of a weaving yarn and a weave density (ends or picks/2.54 cm) of from 10,000 to 25,000 (dtex•ends (or picks)/2.54 cm) in both the warp direction and the weft direction, a silicone being applied to the woven fabric in an amount of from 5 to 25 g/m 2 , and having on one side a uniform silicone coating layer formeding part of the silicone mentioned above. The silicone coated fabric of the present invention is a lightweight coated fabric that shows improved heat resistance, improved flexibility and an improved low coefficient of friction as well as particularly improved burning resistance. The fabric can therefore be used for producing lightweight and compactly storable airbags that suppress bursting starting from a burnt-through-hole, and that shorten a deployment time.

1 . A silicone coated fabric comprising a base woven fabric that is formed from a synthetic fiber weaving yarn having a yarn size of from 100 to 270 dtex, and a woven yarn size parameter expressed by a product calculated by multiplying the yarn size of a weaving yarn and a weave density (ends or picks/2.54 cm) of from 10,000 to 25,000 (dtex•ends (or picks)/2.54 cm) in both the warp direction and the weft direction, a silicone being applied to the woven fabric in an amount of from 5 to 25 g/m 2 , and showing a maximum burning speed of from 70 to 150 kW/m2 in a radiation burning test using a cone calorimeter.  
     
     
         2 . The silicone coated fabric according to  claim 1 , wherein the ratio of a tear strength to a weaving yarn strength according to the single tongue method is from 8 to 15 in both the warp direction and the weft direction.  
     
     
         3 . The silicone coated fabric according to  claim 1  or  2 , wherein the biaxial tensile breaking strength is from 4,000 to 8,000 N/20 cm in both the warp direction and the weft direction.  
     
     
         4 . The silicone coated fabric according to any one of  claims 1  to  3 , wherein in observation by SEM of a cross section of the silicon coated fabric, the Si element distribution determined by SEM/XMA has a maximum peak and other peak showing a count having from {fraction (1/20)} to ⅔ of the peak count in a central 50% portion of a site where a warp and a weft are overlapped by weaving from the front and back sides  
     
     
         5 . The silicone coated fabric according to any one of  claims 1  to  4 , wherein the coefficient of friction (MIU) measured according to KES in both the warp direction and the weft direction is from 0.05 to 0.3 on both the front and back sides of the fabric.  
     
     
         6 . The silicone coated fabric according to any one of  claims 1  to  5 , wherein the air permeation under a pressure of 300 kPa is 1.0 cm 3 /cm 2 /sec or less.  
     
     
         7 . The silicone coated fabric according to any one of  claims 1  to  6 , wherein the fabric shows the following results in a FMVSS 302 burning test: a) the fire goes out within 60 sec of a burning time with a burning distance of 50 mm or less; or b) the fire burns at a burning speed of 80 mm/min or less at a burnt distance (the maximum distance being 254 mm).  
     
     
         8 . The silicone coated fabric according to any one of  claims 1  to  7 , wherein the synthetic fiber weaving yarn is mainly formed from a poly(hexamethylene adipamide), and the single filament size of the weaving yarn is from 0.5 to 4.5 dtex per filament.  
     
     
         9 . A method of producing a silicone coated fabric, which comprises coating a woven fabric that is formed from a synthetic fiber weaving yarn having a yarn size of from 100 to 270 dtex, a woven yarn size parameter determined by a product calculated by multiplying the yarn size and a weave density (ends or picks/2.54 cm) of from 10,000 to 25,000 (dtex•ends (or picks)/2.54 cm) with silicone in an amount of from 5 to 25 g/m 2  by a combination of the two types of applications mentioned in (1) and (2) below, and crosslinking the silicone coating: 
 (1) applying to the woven fabric a dope composed of a silicone composition in an amount of from 1 to 21 g/m 2  as a solid component; and  
 (2) coating the woven fabric with a liquid silicone composition in an amount of from 4 to 24 g/m 2 .  
 
     
     
         10 . An airbag comprising the silicone coated fabric according to any one of  claims 1  to  8 .  
     
     
         11 . An airbag comprising the silicone coated fabric produced by the production method according to  claim 9.