Process for the production of polyurethane urea fibers by including a combination of polydimethylsiloxane, alkoxylated polydimethylsiloxane and a fatty acid salt in the spinning solution

Abstract

Polyurethane urea fibers produced by a dry or wet spinning process and comprising, in finely dispersed or dissolved form, a mixture of polydimethylsiloxane, alkoxylated polydimethylsiloxane and a fatty acid salt; and a process for their production.

1 . Process for the production of polyurethane urea fibers by the dry spinning or wet spinning process, which comprises preparing a polyurethane urea spinning solution, spinning the spinning solution using a spinneret, forming threads beneath the spinneret by removing the spinning solvent either by drying or in a precipitation bath, finishing and optionally twisting and winding the spun fibers, wherein, prior to spinning 
 B) from 0.1 to 5 wt. % polydimethylsiloxane having a viscosity of from 2 to 20 cSt (25° C.),    C) from 0.1 to 5 wt. % alkoxylated polydimethylsiloxane (PDMS) corresponding to the general formula (1)                        wherein PE is the monovalent radical —CH 2 —CH 2 —CH 2 —O(eo v /po w ) m Z, wherein eo=ethylene oxide, po=propylene oxide and Z is either hydrogen or a C 1 -C 6 -alkyl radical,    v and w are integers greater than or equal to 0, wherein v and w are not simultaneously 0,    x, y and m are integers greater than or equal to 1, which are preferably so selected that the number average molecular weight of the compound of formula (1) does not exceed 30,000 g/mol. and the viscosity of component C) is from 10 to 5000 cSt (25° C.), and      D) from 0.01 to 3.0 wt. % of a metal salt of a saturated or unsaturated, mono- or bi-functional C 6 -C 30  fatty acid, wherein the metal is a metal from the first, second or third main group of the periodic system, or is zinc    based on the weight of the finished polyurethane urea fibers.    
     
     
         2 . Process according to  claim 1 , wherein said spinning process is a dry spinning process.  
     
     
         3 . Process according to  claim 1 , wherein said amount of polydimethylsiloxane is from 0.2 to 3 wt. %.  
     
     
         4 . Process according to  claim 3 , wherein said amount of polydimethylsiloxane is from 0.3 to 2 wt %.  
     
     
         5 . Process according to  claim 1 , wherein said amount of alkoxylated polydimethylsiloxane is from 0.2 to 3 wt. %.  
     
     
         6 . Process according to  claim 5 , wherein said amount of alkoxylated polydimethylsiloxane is from 0.3 to 2 wt. %.  
     
     
         7 . Process according to  claim 1 , wherein said amount of metal salt is from 0.05 to 2 wt. %.  
     
     
         8 . Process according to  claim 7 , wherein said amount of metal salt is from 0.1 to 1.5 wt. %.  
     
     
         9 . Process according to  claim 1 , wherein the polyurethane urea content of the spinning solution is adjusted to produce finished polyurethane urea fibers containing from 99.7 to 65 wt. % polyurethane urea.  
     
     
         10 . Process according to  claim 9 , wherein said fibers contain 99.5 to 80 wt. % polyurethane.  
     
     
         11 . Process according to  claim 10 , wherein said fibers contain 99 to 85 wt. % polyurethane.  
     
     
         12 . Process according to  claim 1 , wherein components B), C) and D) are added to the spinning solution in such amounts as will result in a weight ratio of polydimethylsiloxane B) to alkoxylated polydimethylsiloxane C) in the finished fibers of 2:1 to 1:2 and a weight ratio of polydimethylsiloxane B) to fatty acid salt D) of 2:1 to 1:2.  
     
     
         13 . Process according to  claim 1 , wherein the polydimethylsiloxanes B), alkoxylated polydimethylsiloxanes C) and fatty acid salts D) are added to the spinning solution in the form of a 10 to 25 wt. % stock formulation solution in the spinning solvent, based on the sum of the amounts of components B), C) and D).  
     
     
         14 . Process according to  claim 1 , wherein the denier of the finished spun fibers is from 10 to 1280 dtex.  
     
     
         15 . Polyurethane urea fibers comprising 
 A) from 99.7 to 65 wt. % polyurethane urea polymer,    B) from 0.1 to 5 wt. % polydimethylsiloxane having a viscosity of from 2 to 20 cSt (25° C.),    C) from 0.1 to 5 wt. % alkoxylated polydimethylsiloxane (PDMS) corresponding to the general formula (1)                        wherein    PE is the monovalent radical —CH 2 —CH 2 —CH 2 —O(eo v /po w ) m Z,    eo represents ethylene oxide,    po represents propylene oxide and    Z is either hydrogen or a C 1 -C 6 -alkyl radical,    v and w are integers greater than or equal to 0, wherein v and w are not simultaneously 0,    x, y and m are integers greater than or equal to 1, which are preferably so selected that the number average molecular weight of the compound of formula (1) does not exceed 30,000 g/mol. and the viscosity of component C) is from 10 to 5000 cSt (25° C.),      D) from 0.01 to 3 wt. % of a metal salt of a saturated or unsaturated, mono- or bi-functional C 6 -C 30  fatty acid, wherein the metal is a metal selected from the first, second or third main group of the periodic system, or is zinc, and    E) from 0 to 20 wt. % additives, 
 wherein the polydimethylsiloxane, the alkoxylated polydimethylsiloxane and the fatty acid salt are finely dispersed or dissolved in the fibers.  
   
     
     
         16 . Polyurethane urea fibers according to  claim 15 , wherein said amount of polyurethane urea polymer is from 99.5 to 80 wt. %.  
     
     
         17 . Polyurethane urea fibers according to  claim 16 , wherein said amount of polyurethane urea polymer is from 99 to 85 wt. %.  
     
     
         18 . Polyurethane urea fibers according to  claim 15 , wherein said amount of polydimethylsiloxane is from 0.2 to 3 wt. %.  
     
     
         19 . Polyurethane urea fibers according to  claim 18 , wherein said amount of polydimethylsiloxane is from 0.3 to 2 wt. %.  
     
     
         20 . Polyurethane urea fibers according to  claim 15 , wherein said amount of alkoxylated polydimethylsiloxane is from 0.2 to 3 wt. %.  
     
     
         21 . Polyurethane urea fibers according to  claim 20 , wherein said amount of alkoxylated polydimethylsiloxane is from 0.3 to 2 wt. %.  
     
     
         22 . Polyurethane urea fibers according to  claim 15 , wherein said amount of metal salt is from 0.05 to 2 wt. %.  
     
     
         23 . Polyurethane urea fibers according to  claim 22 , wherein said amount of metal sale is from 0.1 to 1.5 wt. %.  
     
     
         24 . Polyurethane urea fibers according to  claim 15 , wherein said amount of additives is from 0 to 15 wt. %.  
     
     
         25 . Elastic fabrics, knitted goods, or hosiery comprising the polyurethane urea fibers of  claim 15.