Pyrotechnic compositions for gas generant apllications

Abstract

Pyrotechnic compositions which include about 45 to about 90 weight percent of a fuel material of cobalt III nitrate complex with ammonia or water ligands, and about 10 to about 55 weight percent of a combination of a combination of a burn rate catalyst of copper bis ethylenediamine dinitrate and an oxidizer of basic copper nitrate are provided to result in relatively high gas outputs and burn rates. The compositions desirably include the cobalt III nitrate complex in a greater relative amount than either the copper complex of ethylenediamine dinitrate or the basic copper nitrate; the copper complex of ethylenediamine dinitrate is present in a relative amount of at least about 2 weight percent and the basic copper nitrate is present in a relative amount of at least 1.5 times the relative amount of the copper complex of ethylenediamine dinitrate. Also provided are corresponding or associated gas generating devices and inflatable vehicle occupant safety restraint systems.

What is claimed is:  
     
         1 . A pyrotechnic composition comprising: 
 about 45 to about 90 weight percent cobalt III nitrate complex with ligands selected from the group consisting of ammonia and water and    about 10 to about 55 weight percent of a combination of: a) a copper complex of ethylenediamine dinitrate and b) basic copper nitrate;    wherein the composition includes the cobalt III nitrate complex in a greater relative amount than either the copper complex of ethylenediamine dinitrate or the basic copper nitrate; the copper complex of ethylenediamine dinitrate is present in a relative amount of at least about 2 weight percent and the basic copper nitrate is present in a relative amount of at least 1.5 times the relative amount of the copper complex of ethylenediamine dinitrate.    
     
     
         2 . The pyrotechnic composition of  claim 1  wherein the copper complex of ethylenediamine dinitrate is copper bis ethylenediamine dinitrate.  
     
     
         3 . The pyrotechnic composition of  claim 1  wherein the cobalt III nitrate complex is a hexadentate cobalt III nitrate complex.  
     
     
         4 . The pyrotechnic composition of  claim 3  wherein the hexadentate cobalt III nitrate complex is a hexadentate neutral cobalt III nitrate complex.  
     
     
         5 . The pyrotechnic composition of  claim 1  wherein the cobalt III nitrate complex is selected from the group consisting of hexammine cobalt III nitrate, pentammineaquo cobalt III nitrate and mixtures thereof.  
     
     
         6 . The pyrotechnic composition of  claim 1  formed by: 
 combining 
 a. the cobalt III nitrate complex with ligands selected from the group consisting of ammonia and water with,  
 b. sufficient cupric nitrate and ethylenediamine to form the copper bis ethylenediamine dinitrate and  
 c. the basic copper nitrate to form a mixture and  
 
 spray drying the mixture to form a powder form of the pyrotechnic composition.  
 
     
     
         7 . The pyrotechnic composition of  claim 6  wherein the powder form of the pyrotechnic composition is press-formed into a desired form.  
     
     
         8 . The pyrotechnic composition of  claim 1  consisting essentially of: 
 the cobalt III nitrate complex with ligands selected from the group consisting of ammonia and water;  
 the copper complex of ethylenediamine dinitrate; and  
 basic copper nitrate.  
 
     
     
         9 . The pyrotechnic composition of  claim 1  wherein the composition provides a burn rate of at least about 0.4 ips at 1000 psi.  
     
     
         10 . The pyrotechnic composition of  claim 1  wherein the pyrotechnic composition provides a gas output of at least about 3.3 moles per 100 grams of pyrotechnic composition.  
     
     
         11 . A gas generating device containing the pyrotechnic composition of  claim 1 .  
     
     
         12 . An inflatable vehicle occupant safety restraint system comprising: 
 the gas generating device of  claim 11  connected in association with an inflatable airbag cushion for inflating the airbag cushion.    
     
     
         13 . A pyrotechnic composition comprising: 
 about 45 to about 90 weight percent hexammine cobalt III nitrate;    about 2 to about 20 weight percent copper bis ethylenediamine dinitrate; and    basic copper nitrate in a relative amount of at least about 1.5 times that of the copper bis ethylenediamine dinitrate,    wherein the composition provides a burn rate of in excess of 0.35 ips at 1000 psi and a gas output of at least about 3.0 moles per 100 grams of the composition.    
     
     
         14 . The pyrotechnic composition of  claim 13  wherein the copper bis ethylenediamine dinitrate and the basic copper nitrate are present in total relative amount of about 10 to about 55 composition weight percent.  
     
     
         15 . The pyrotechnic composition of  claim 13  consisting essentially of: hexammine cobalt III nitrate, copper bis ethylenediamine dinitrate and basic copper nitrate.  
     
     
         16 . The pyrotechnic composition of  claim 13  wherein the composition provides a burn rate of at least about 0.4 ips at 1000 psi.  
     
     
         17 . The pyrotechnic composition of  claim 13  formed by: 
 combining 
 a. the hexammine cobalt III nitrate with,  
 b. sufficient cupric nitrate and ethylenediamine to form the copper bis ethylenediamine dinitrate and  
 c. the basic copper nitrate to form a mixture and  
 
 spray drying the mixture to form a powder form of the pyrotechnic composition.  
 
     
     
         18 . The pyrotechnic composition of  claim 17  wherein the powder form of the pyrotechnic composition is press-formed into a desired form.  
     
     
         19 . A gas generating device containing the pyrotechnic composition of  claim 13 .  
     
     
         20 . An inflatable vehicle occupant safety restraint system comprising: 
 the gas generating device of  claim 19  connected in association with an inflatable airbag cushion for inflating the airbag cushion.