Ply yarn having twisted hollow fiber and heat retention fiber

Abstract

A yarn is provided with a hollow fiber including a plurality of filaments and one or more longitudinal voids between the filaments; and a heat retention fiber being a fiber for emitting infrared light, the heat retention fiber including a plurality of filaments each being capable of retaining heat, the filaments having nanoscale powder capable of emitting near and far infrared light uniformly formed therein. The hollow fiber and the heat retention fiber are twisted together to form a yarn having heat retention capability.

What is claimed is: 
     
         1 . A yarn comprising:
 a hollow fiber including a plurality of filaments and one or more longitudinal voids between the filaments; and   a heat retention fiber being a fiber for emitting infrared light, the heat retention fiber including a plurality of filaments each being capable of retaining heat, the filaments having nanoscale powder capable of emitting near and far infrared light uniformly formed therein;   wherein the hollow fiber and the heat retention fiber are twisted together to form a ply yarn having heat retention capability.   
     
     
         2 . The yarn of  claim 1 , wherein the one or more voids occupy at least 15% of a cross sectional area of the hollow fiber. 
     
     
         3 . The yarn of  claim 1 , wherein the nanoscale powder has a diameter D90 equal to or less than 350 nm. 
     
     
         4 . The yarn of  claim 1 , wherein the filaments of each of the hollow fiber and the heat retention fiber are selected from the group consisting of polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), acrylic fiber, rayon, nylon, and polypropylene (PP). 
     
     
         5 . The yarn of  claim 1 , wherein after extruding the filaments of each of the hollow fiber and the heat retention fiber, a fully drawn yarn (FDY) device is activated to draw the filaments of each of the hollow fiber and the heat retention fiber and an air-textured yarn (ATY) device is subsequently activated to air texturize the filaments of each of the hollow fiber and the heat retention fiber so as to twist them to finish the yarn having heat retention capability; and wherein the hollow fiber has a contraction ratio of 3% to 8% and the heat retention fiber has a contraction ratio of 10% to 25%. 
     
     
         6 . The yarn of  claim 1 , wherein the hollow fiber has a weight fraction of 25-75% and the heat retention fiber has a weight fraction of 75-25%. 
     
     
         7 . The yarn of  claim 1 , wherein the yarn is in the range from 50 to 300 denier and number of uniform filaments (f) of the yarn is in the range from 48 to 578. 
     
     
         8 . The yarn of  claim 1 , wherein a textile product made from the yarns having infrared light emission rate equal to or greater than 80%, near infrared light absorption rate equal to or greater than 65%, temperature increase equal to or greater than 5° C., and a heat retention coefficient per unit area equal to or greater than 0.4. 
     
     
         9 . The yarn of  claim 1 , wherein the yarn includes a plurality of fluffs on its outer surface.