High load bearing capacity nylon staple fibers with additive, and blended yarns and fabrics thereof

Abstract

Nylon staple fiber with additive exhibiting a break tenacity greater than 6.5 g/den are provided as well as yarns, fabrics and other articles of manufacture produced from the fiber. Methods for producing the nylon staple fiber with additive are also provided.

1 . A nylon staple fiber comprising:
 a nylon polymer; and   an additive,   wherein the nylon staple fiber has a break tenacity greater than 6.5 g/den.   
     
     
         2 . The nylon staple fiber of  claim 1  wherein the additive is selected from a pigment, an additive for ultraviolet (UV) protection or an additive for flame or fire (FR) resistance. 
     
     
         3 . The nylon staple fiber of  claim 1  wherein the additive is a pigment present in an amount from about 10 parts per million to about 50,000 parts per million. 
     
     
         4 . The nylon staple fiber of  claim 1  wherein the nylon polymer is selected from the group consisting of nylon 6,6, nylon 6, and combinations thereof. 
     
     
         5 . The nylon staple fiber of  claim 1  wherein the nylon polymer further comprises a monomeric salt of sulfonated isopthalate (SPA) in an amount of about 0.04 to about 4 wt % nylon polymer. 
     
     
         6 . The nylon staple fiber of  claim 1  wherein the nylon polymer further comprises a monomeric methylpentamethyldiamine (MPMD) in an amount of about 0.04 to about 4 wt. % nylon polymer. 
     
     
         7 . The nylon staple fiber of  claim 1  wherein the tenacity at 10% elongation is greater than 3.0 g/den. 
     
     
         8 . A yarn spun from the nylon staple fiber of  claim 1 . 
     
     
         9 . The yarn of  claim 8  further comprising at least one companion staple fiber. 
     
     
         10 . The yam of  claim 9  wherein the companion staple fiber is selected from the group consisting of cellulosics, modified cellulosics, animal fibers, fire resistant polyester, fire resistant nylon, fire resistant rayon, fire resistant treated cellulose, m-aramid, p-aramid, modacrylic, novoloid, melamine, polyvinyl chloride, antistatic fiber, PBO (1,4-benzenedicarboxylic acid, polymer with 4,6-diamino-1,3-benzenediol dihydrochloride) and PBI (polybenzimidazole), and combinations thereof. 
     
     
         11 . The yarn of  claim 1  wherein the nylon content is 5% or greater. 
     
     
         12 . An article of manufacture at least a portion of which comprises nylon staple fiber of  claim 1 . 
     
     
         13 . The article of manufacture of  claim 12  which is a fabric. 
     
     
         14 . The article of manufacture of  claim 12  which is a denim fabric. 
     
     
         15 . (canceled) 
     
     
         16 . The article of manufacture of  claim 12  which is a non-woven fabric composite. 
     
     
         17 - 26 . (canceled) 
     
     
         27 . A method for producing high strength or load bearing nylon staple fiber with additive, said method comprising:
 melt-spinning nylon polymer with additive into filaments;   uniformly quenching the filaments;   forming a tow from a multiplicity of these quenched filaments;   subjecting the tow to drawing in the presence of steam,   annealing the drawn tow; and   converting the resulting drawn and annealed tow into staple fibers.   
     
     
         28 . The method of  claim 27  wherein the additive is selected from a pigment, an additive for UV protection or an additive for FR resistance. 
     
     
         29 . The method of  claim 27  wherein annealing is performed under tension. 
     
     
         30 . The method of  claim 27  wherein the nylon staple fiber has a break tenacity greater than 6.5 g/den. 
     
     
         31 . The method of  claim 27  wherein the nylon staple fiber has a tenacity at 10% elongation of greater than 3.0 g/den.