High loft nonwoven fabric

Abstract

A nonwoven fabric having fibers composed of a polymeric blend of a polymer and a high loft additive. The nonwoven fabric exhibits increases in thickness, sound absorbance, and thermal resistance in comparison to a similar nonwoven fabric not having the high loft additive.

1 . A nonwoven fabric comprising a plurality of fibers, the fibers comprising a polymeric blend of a polymer resin and a high loft additive, and wherein the fabric exhibits a percent increase in thickness of at least 20% in comparison to a similarly prepared nonwoven fabric that does not include the high loft additive. 
     
     
         2 . The nonwoven fabric according to  claim 1 , wherein the nonwoven fabric comprises a meltblown fabric. 
     
     
         3 . The nonwoven fabric according to  claim 1 , wherein the high loft additive comprises a fatty acid amide. 
     
     
         4 . The nonwoven fabric according to  claim 1 , wherein the high loft additive has the following formula (1): 
       
         
           
           
               
               
           
         
       
       wherein R 1  comprises a C 10 -C 22  carbon chain, which may be saturated or unsaturated, and R 2 , independently, is selected from H, a C 1 -C 4  alkyl group, R 1 , and R 3 , wherein R 3  has the following formula (2):
   —(C 1 -C 4 )C(═O)N(R 5 )(R 1 )   (2)
 
 
       wherein R 5  is H or a C 1 -C 4 alkyl group. 
     
     
         5 . The nonwoven fabric according to  claim 4 , wherein the high loft additive comprises a fatty acid amide having two amide groups of the general formula (2) 
       
         
           
           
               
               
           
         
       
       wherein R 1 , independently, comprises an aliphatic carbon chain having from C 10 -C 22 , and R 2  is a C 1 -C 4  group, and R 4  is selected from —C(═O)NH(R 1 ), —C(═O)N(R 1 ) 2 , and —C(═O)NH 2 , —C(═O)N(R 5 )(R 1 ), and —C(═O)N(R 5 ) 2 , and wherein R 5  is as defined previously. 
     
     
         6 . The nonwoven fabric according to  claim 1 , wherein the high loft additive comprises an aliphatic amide having two amide groups of the following formula (4): 
       
         
           
           
               
               
           
         
       
       wherein each R 1 , independently, comprises an aliphatic C 10 -C 22  carbon chain, which may be saturated or unsaturated, and R 2  comprises a C 1 -C 4  alkyl group. 
     
     
         7 . The nonwoven fabric according to  claim 1 , wherein the fatty acid amide comprises one or more of erucamide, oleamide, and stearamide behenamide, octadecane amide, ethylene bis-stearamide, and stearyl erucamide. and the like. In a preferred embodiment, the high loft additive comprises an aliphatic bis alkyl amide, such as N, N′-ethylene bis-stearamide. 
     
     
         8 . The nonwoven fabric according to  claim 1 , wherein the fatty acid amide is N, N′-ethylene bis-stearamide. 
     
     
         9 . The nonwoven fabric according to  claim 1 , wherein the amount of the high loft additive in the polymeric blend is from about 0.0125 weight percent to about 2.5 weight percent, based on the total weight of the fiber. 
     
     
         10 . The nonwoven fabric according to  claim 1 , wherein the amount of the high loft additive in the polymeric blend is from about 0.05 weight percent to about 2.0 weight percent, based on the total weight of the fiber. 
     
     
         11 . The nonwoven fabric according to  claim 1 , wherein the fibers have a sheath/core configuration and the high loft additive is only present in the sheath. 
     
     
         12 . The nonwoven fabric according to  claim 1 , wherein the fibers are monocomponent. 
     
     
         13 . The nonwoven fabric according to  claim 1 , wherein the fibers of the nonwoven fabric are not bonded. 
     
     
         14 . The nonwoven fabric according to  claim 1 , wherein the fibers of the nonwoven fabric are air through bonded. 
     
     
         15 . The nonwoven fabric according to  claim 1 , wherein the basis weight of the nonwoven fabric is selected from the group consisting of from about 150 to 800 gsm, from about 250 to 750 gsm, from about 300 to 750 gsm, from about 350 to 600 gsm, and from about 400 to 550 gsm. 
     
     
         16 . The nonwoven fabric according to  claim 15 , wherein the nonwoven fabric comprises a meltblown fabric, and wherein the fibers have a mean fiber diameter ranging from about 3.5 to 4.5 microns with a standard deviation of less than 2 microns. 
     
     
         17 . The nonwoven fabric according to according to  claim 1 , wherein the nonwoven fabric exhibits a percent increase in Average Absorption Coefficient (AAC) from 20 to 250% in comparison to a similarly prepared nonwoven fabric that does not include the high loft additive. 
     
     
         18 . The nonwoven fabric according to  claim 1 , wherein the nonwoven fabric exhibits a percent increase in thickness from about 20 to 250% in comparison to a similarly prepared nonwoven fabric that does not include the high loft additive. 
     
     
         19 . The nonwoven fabric according to  claim 1 , wherein the nonwoven fabric exhibits a percent increase in thickness selected from the group consisting of 20 to 220%, 20 to 200%, 30 to 190%, 40 to 80%, 45 to 150%, 80 to 140%, and 45 to 55% in comparison to a similarly prepared nonwoven fabric that does not include the high loft additive. 
     
     
         20 . The nonwoven fabric according to  claim 1 , wherein the nonwoven fabric exhibits a percent increase in thermal resistance from about 25 to 500% in comparison to a similarly prepared nonwoven fabric that does not include the high loft additive. 
     
     
         21 . The nonwoven fabric according to  claim 1 , wherein the nonwoven fabric exhibits a thermal resistance selected from the group consisting of from about 0.100 to 0.500 K·m 2 /Watt, from about 0.125 to 0.300 K·m 2 /Watt, from about 0.150 to 0.225 K·m 2 /Watt, and from 0.160 to 0.200 K·m 2 /Watt. 
     
     
         22 . A meltblown nonwoven fabric comprising a plurality of meltblown fibers, the meltblown fibers comprising a blend of an olefin resin and a fatty acid amide of the following formula (1): 
       
         
           
           
               
               
           
         
       
       wherein R 1  comprises a C 10 -C 22  carbon chain, which may be saturated or unsaturated, and R 2 , independently, is selected from H, a C 1 -C 4  alkyl group, R 1 , and R 3 , wherein R 3  has the following formula (2):
   —(C 1 -C 4 )C(═O)N(R 5 )(R 1 )   (2)
 
 
       wherein R 3  is H or a C 1 -C 4  alkyl group, and wherein the meltblown nonwoven fabric exhibits a percent increase in thickness of at least 20% in comparison to a similarly prepared nonwoven fabric that does not include the fatty acid amide.