Process of making cellulosic fibers including ptfe

Abstract

The present invention is directed to a method for making solution spun fibers having decreased coefficient of friction and other improved properties such as wear resistance and the like, when compared to conventional solution spun fibers. In the method of the present invention, polytetrafluoroethylene (PTFE) is incorporated into the fiber-forming substance during the solution spinning process before passing through the spinneret. PTFE that is useful in the present invention includes PTFE powder that is dispersible to low micron or submicron particle size and aqueous or organic dispersions of such highly dispersible PTFE powder. The present invention is also directed to fabrics, textiles, and other articles of manufacture formed from the PTFE-enhanced solution spun fibers of the present invention.

1 . A method for making a fiber, comprising: 
 preparing a viscose of soluble fiber-forming material;    adding polytetrafluoroethylene (PTFE) material to the soluble fiber-forming material during the preparation of the viscose;    forcing the viscose having the added PTFE material through a spinneret into a wet bath to form the fiber.    
     
     
         2 . The method of  claim 1 , wherein adding the PTFE material to the fiber-forming material comprises dispersing PTFE particles having a size less than about one micron into the viscose.  
     
     
         3 . The method of  claim 1 , wherein adding the PTFE material to the fiber-forming material comprises adding PTFE powder that is dispersible to submicron particle size.  
     
     
         4 . The method of  claim 1 , wherein adding the PTFE material to the fiber-forming material comprises adding an aqueous dispersion of PTFE powder that is dispersible to low micron particle size.  
     
     
         5 . The method of  claim 4  wherein the aqueous solvent dispersion of PTFE powder comprises about 20% to about 60% PTFE by weight.  
     
     
         6 . The method of  claim 1 , wherein adding the PTFE material to the fiber-forming material comprises adding an organic solvent dispersion of PTFE powder that is dispersible to low micron particle size.  
     
     
         7 . The method of  claim 1 , wherein adding the PTFE material to the fiber-forming material comprises dispersing PTFE particles that have a size smaller than a channel size of the spinneret.  
     
     
         8 . The method of  claim 1 , wherein adding the PTFE material to the fiber-forming material comprises introducing dispersible PTFE powder in the form of a pelletized master batch.  
     
     
         9 . The method of  claim 8 , wherein the master batch comprises about 5% PTFE to about 60% PTFE.  
     
     
         10 . The method of  claim 1 , wherein the fiber-forming material comprises material selected from the group of cellulose, compounds of cellulose and any combination thereof.  
     
     
         11 . The method of  claim 1 , wherein preparing a viscose of fiber-forming material; comprise the steps of steeping, pressing, shredding, aging, xanatahation, dissolving, ripening, filtering, and degassing, and wherein adding polytetrafluoroethylene (PTFE) material to the fiber-forming material during the preparation of the viscose comprises adding PTFE during at least one of the steps in preparing the viscose.  
     
     
         12 . The method of  claim 1 , wherein forcing the viscose having the added PTFE material through a spinneret into a solution to form the fiber, further comprises solidifying the forced viscose such that the PTFE particles are dispersed substantially through out the body of the fiber.  
     
     
         13 . A fabric comprising fibers made by the method of  claim 1 .  
     
     
         14 . A synthetic fiber, comprising: 
 a wet spun extrusion of cellulose material; and    a dispersion of PTFE particles in the wet spun extrusion.    
     
     
         15 . The synthetic fiber of  claim 14  wherein the PTFE particles are distributed substantially homogeneously through the wet spun extrusion.  
     
     
         16 . The synthetic fiber of  claim 14  wherein the dispersion of PTFE particles comprises PTFE particles having a size less than about one micron.  
     
     
         17 . A fabric comprising the synthetic fiber of  claim 14 .  
     
     
         18 . An article of manufacture comprising the synthetic fiber of  claim 14.