Pyrotechnic gas-generating composition intended for motor vehicle safety and burning at combustion temperatures below 2200 degree K

Abstract

The present invention relates to a gas-generating pyrotechnic composition, this composition being characterized in that it comprises a first oxidizing charge consisting of ammonium perchlorate and a second oxidizing charge consisting of a metal oxide chosen from the group consisting of copper oxide, manganese oxide and a mixture of these two compounds, the weight ratio between the first oxidizing charge and the second oxidizing charge being less than 1, the said composition also including a reducing charge in the form of a nitrogen-containing organic compound chosen from the group consisting of nitroguanidine, guanidinium nitrate, oxamide, dicyandiamide and metal cyanamides.

1 . Gas-generating pyrotechnic composition, characterized in that it comprises a first oxidizing charge consisting of ammonium perchlorate present at a weight concentration between 15 and 30% of the total weight of the composition, and a second oxidizing charge consisting of a metal oxide chosen from the group consisting of copper oxide, manganese oxide and a mixture of these two compounds, the weight ratio between the first oxidizing charge and the second oxidizing charge being less than 1, the said composition also including a reducing charge in the form of a nitrogen-containing organic compound chosen from the group consisting of nitroguanidine, guanidinium nitrate, oxamide, dicyandiamide and metal cyanamides.  
     
     
         2 . Composition according to  claim 1 , characterized in that it includes a binder chosen from the group consisting of a methyl cellulose and polyvinyl alcohol.  
     
     
         3 . Composition according to  claim 2 , characterized in that the binder is sodium carboxymethylcellulose (Na-25 CMC).  
     
     
         4 . Composition according to  claim 2 , characterized in that the weight concentration of the binder represents a maximum of 6% of the total weight of the composition.  
     
     
         5 . Composition according to  claim 1 , characterized in that the composition includes additives facilitating its manufacture.  
     
     
         6 . Composition according to  claim 1 , characterized in that the nitrogen-containing organic compound has a weight concentration between 30 and 50% of the total weight of the composition.  
     
     
         7 . Composition according to  claim 1 , characterized in that the weight concentration of the second oxidizing charge lies between 30 and 45% of the total weight of the composition.  
     
     
         8 . Composition according to  claim 1 , characterized in that the metal cyanamides consist of the cyanamides of sodium, zinc and copper.  
     
     
         9 . Composition according to  claim 8 , characterized in that the metal cyanamide is zinc cyanamide ZnCN 2 .  
     
     
         10 . Composition according to  claim 1 , characterized in that it includes additives acting as combustion catalysts or agents for trapping solid particles emitted during combustion.  
     
     
         11 . Composition according to  claim 1 , characterized in that it is manufactured and formed by a pelleting or disc compression process.  
     
     
         12 . Composition according to  claim 2 , characterized in that it is manufactured and formed by an extrusion process.  
     
     
         13 . Composition according to  claim 3 , characterized in that the weight concentration of the binder represents a maximum of 6% of the total weight of the composition.