Polyester fiber for false twisting

Abstract

The polytrimethylene terephthalate-based polyester yarn, which has excellent smoothness, heat resistance, collectability and anti-electricity, scarcely generates fluffs and broken yarn, and can stably be subjected to false-twisting, is a polyester yarn whose 80% or more by weight is formed from polytrimethylene terephthalate, which has a birefringence of 0.03 to 0.08, an elongation of 30 to 180%, an elastic recovery of 30 to 100% at 10% elongation, and to whose surface a treating agent, containing an ether-ester compound (the component a) represented by the following formula in an amount of 50 to 80% by weight and a polyether compound (the component b) having a molecular weight of 10,000 or more in an amount of 2 to 20% by weight, is stuck in an amount of 0.2 to 1.0% by weight. R 1 OCO—(A) X —(CH 2 ) Z —(A) Y —COOR 2 [wherein, R 1 and R 2 are each an alkyl group having 7 to 21 carbon atoms, A is an oxyalkylene group having 2 to 4 carbon atoms, X and Y are each an integer of not less than 0, provided that (X+Y) is an integer of 1 to 20, and Z is an integer of 3 to 12].

1 . A polyester yarn for false-twisting characterized in that 80% or more by weight of the polymer component constituting the yarn comprises trimethylene terephthalate units, in that said yarn has a birefringence of 0.03 to 0.08, an elongation of 30 to 180%, and an elastic recovery of 30 to 100% at 10% elongation, and in that a treating agent containing the following components a and b is stuck to the surface of said yarn in an amount of 0.2 to 1.0% by weight based on the weight of the yarn. 
 The components of the treating agent and contents thereof;    a. An ether-ester compound represented by the following general formula: a content of 50 to 80% by weight;   R 1 OCO—(A) X —(CH 2 ) Z —(A) Y —COOR 2     [wherein, R 1  and R 2  are each an alkyl group having 7 to 21 carbon atoms, A is an oxyalkylene group having 2 to 4 carbon atoms, X and Y are each an integer of not less than 0, provided that (X+Y) is an integer of 1 to 20, and Z is an integer of 3 to 12] and    b. A polyether compound having a molecular weight of 10,000 or more: a content of 2 to 20% by weight.    
     
     
         2 . The polyester yarn for false-twisting according to  claim 1 , wherein the molecular weight of the polyether compound is 20,000 to 50,000.  
     
     
         3 . The polyester yarn for false-twisting according to  claim 1  or  2 , wherein the polyether compound is a copolyether in which the copolymerization weight ratio (PO/EO) of propylene oxide (PO)/ethylene oxide (EO) is 20/80 to 50/50.