Dyeing of modacrylic/aramid fiber blends

Abstract

A method of dyeing a blend of modacrylic fiber and aramid fiber employing a cationic dye and dye assistant employs a concentration of dye assistants not greater than 10 grams per liter of dye bath.

1 . A method of dyeing a blend of modacrylic fiber and aramid fiber employing a cationic dye and a dye assistant wherein the modacrylic fiber is present in range of 1 to 99 weight % and the aramid fiber is present in a range from 99 to 1 weight % on the basis of modacrylic fiber and aramid fiber comprising the step of: 
 contacting the blend at a temperature in a range from 70 to 100 degrees C. in an aqueous dye bath containing a cationic dye and a dye assistant present in an amount not greater than 15 grams per liter of dye bath, said dye assistant selected from the group consisting of aryl ether, benzyl alcohol, N-cyclohexylpyrrolidone, N,N-dibutylformamide, N,N-diethylbenzamide, hexadecyltrimethyl ammonium salt, N,N-dimethylbenzamide, N,N-diethyl-m-toluamide, N-octylpyrrolidone, blend of N,N-dimethylcaprylamide and N,N-dimethylcapramide and mixtures thereof.    
     
     
         2 . The method of  claim 1  wherein the fibers are present as a yarn.  
     
     
         3 . The method of  claim 1  wherein the fibers are present in a fabric.  
     
     
         4 . The method of  claim 1  with 40 to 70 weight % modacrylic fiber, 5 to 20 weight percent p-aramid fiber and 10 to 40 weight % m-aramid fiber on a basis of the modacrylic and aramid fibers.  
     
     
         5 . The method of  claim 1  wherein the blend additionally contains an abrasion resistant fiber.  
     
     
         6 . The method of  claim 5  wherein the abrasion resistant fiber is nylon.  
     
     
         7 . The method of  claim 1  wherein the blend contains an antistatic component.  
     
     
         8 . The method of  claim 1  wherein the dye assistant is present in an amount not greater than 12 grams per liter of dye bath.  
     
     
         9 . The method of  claim 8  wherein the dye assistant is present in an amount not greater than 10 grams per liter of dye bath.  
     
     
         10 . The method of  claim 1  wherein the dye assistant is aryl ether or benzyl alcohol.  
     
     
         11 . A garment which includes a blend of fibers dyed by the method of  claim 1.