Flame-Resistant Fabric

Abstract

A flame-resistant fabric containing staple yarns which contain non-FR cellulosic fibers, modacrylic fibers, and non-flammable para-aramid fibers intimately blended together. The staple yarns contain between about 35 and 55 wt. % non-FR cellulose fibers, between about 30 and 45 wt. % modacrylic fibers, and less than 10 wt. % para-aramid fibers. The staple yarns comprising a greater amount by weight of non-FR cellulosic fibers than modacrylic fibers. The non-flammable para-aramid fibers comprise an energy absorbing additive to form energy absorbing fibers and the flame-resistant fabric contains less than 11 wt. % of energy absorbing fibers based on the total weight of the flame-resistant fabric. The flame-resistant fabric has an arc resistance according to ASTM F1959/F1959M-14e1 of at least 1.33 calories per square centimeter per ounce per square yard of fabric.

What is claimed is: 
     
         1 . A flame-resistant fabric comprising staple yarns, wherein the staple yarns comprise an intimate blend of:
 non-FR cellulosic fibers, wherein the staple yarns comprise between about 35 and 55 wt. % non-FR cellulose fibers;   modacrylic fibers, wherein the staple yarns comprise between about 30 and 45 wt. % modacrylic fibers and wherein the staple yarns comprising a greater amount by weight of non-FR cellulosic fibers than modacrylic fibers;   non-flammable para-aramid fibers, wherein the staple yarns comprise less than 10 wt. % para-aramid fibers, and wherein the non-flammable para-aramid fibers comprise an energy absorbing additive to form energy absorbing fibers; and,   wherein the flame-resistant fabric has an arc resistance according to ASTM F1959/F1959M-14e1 of at least 1.33 calories per square centimeter per ounce per square yard of fabric and wherein the flame-resistant fabric comprises less than 11 wt. % of energy absorbing fibers based on the total weight of the flame-resistant fabric.   
     
     
         2 . The flame-resistant fabric of  claim 1 , wherein the non-FR cellulosic fibers comprise non-FR synthetic cellulosic fibers. 
     
     
         3 . The flame-resistant fabric of  claim 1 , wherein the energy absorbing additive is carbon black. 
     
     
         4 . The flame-resistant fabric of  claim 1 , wherein the fabric has an arc rating to fabric weight ratio of at least about 1.5. 
     
     
         5 . The flame-resistant fabric of  claim 1 , wherein the fabric has an arc rating of least about 10 calories/cm 2 . 
     
     
         6 . The flame-resistant fabric of  claim 1 , wherein the fabric has a weight of less than about 5.75 ounces per square yard. 
     
     
         7 . The flame-resistant fabric of  claim 1 , wherein the fabric is a woven fabric. 
     
     
         8 . The flame-resistant fabric of  claim 1 , wherein the fabric is a knit fabric. 
     
     
         9 . The flame-resistant fabric of  claim 1 , wherein the fabric is a non-woven fabric. 
     
     
         10 . The flame-resistant fabric of  claim 1 , wherein the fabric has a weight of less than about 7.0 ounces per square yard. 
     
     
         11 . The flame-resistant fabric of  claim 1 , wherein the fabric has an average char length less than 4 inches when tested in accordance with ASTM D6413. 
     
     
         12 . The flame-resistant fabric of  claim 1 , wherein the fabric has a thermal shrinkage less than 10% when tested in accordance with NFPA 2112-2012. 
     
     
         13 . The flame-resistant fabric of  claim 1 , wherein the staple fibers have an average length of between about 0.5 and 3 inches. 
     
     
         14 . A garment constructed from the flame-resistant fabric of  claim 1 .