Composite fiber, structural yarn, woven and knitted fabric, and clothing

Abstract

A composite fiber is described that satisfies both properties of stretchability and wear resistance, and that exhibits high sensitiveness of a carded wool material characterized by softness, deep color development, and bulkiness, and including a combined filament composite fiber, woven or knitted fabric, and clothing including the composite fiber, where the composite fiber includes a polyester-based thermoplastic resin A and a polyester-based thermoplastic resin B, and satisfies the requirements: (1) through (5) as described herein.

1 . A composite fiber comprising a polyester-based thermoplastic resin A and a polyester-based thermoplastic resin B, wherein the composite fiber satisfying following requirements:
 (1) a difference (M A −M B ) between a weight-average molecular weight M A  of the polyester-based thermoplastic resin A and a weight-average molecular weight M B  of the polyester-based thermoplastic resin B is 2000 to 15000;   (2) an apparent thick-to-thin ratio (D thick /D thin ) of the composite fiber is 1.00 to 1.04;   (3) a crimp elongation rate of the composite fiber is 3.0 to 25.0%;   (4) in a cross-section of the composite fiber, the polyester-based thermoplastic resin B covers the polyester-based thermoplastic resin A, and a ratio (t min /D) of a minimum value t min  of a thickness t of the polyester-based thermoplastic resin B to a fiber diameter D of the composite fiber is 0.01 to 0.10; and   (5) in the cross-section of the composite fiber, a length C t  of a portion in which a region having the thickness t satisfying 1.00t min ≤t≤1.05t min  and a circumferential line of the composite fiber are overlapped satisfies C t ≥0.33C with respect to a circumferential length C of the entire composite fiber.   
     
     
         2 . The composite fiber according to  claim 1 , wherein at least one type of another thread coexists in a form of a combined filament composite fiber subjected to mixing. 
     
     
         3 . The composite fiber according to  claim 2 , wherein the other thread is a latent crimping yarn. 
     
     
         4 . A structural yarn wherein cracks are made on an entire circumference of the surface of the composite fiber according to  claim 1 . 
     
     
         5 . The structural yarn according to  claim 4 , wherein at least one type of another thread coexists in a form of a combined filament composite fiber subjected to mixing. 
     
     
         6 . The structural yarn according to  claim 5 , wherein the other thread is an explicit crimping yarn. 
     
     
         7 . A woven or knitted fabric made by weaving or knitting, using the composite fiber according to  claim 1  in at least a portion of the woven or knitted fabric. 
     
     
         8 . A woven or knitted fabric comprising the structural yarn according to  claim 4  in at least a portion of the woven or knitted fabric. 
     
     
         9 . Clothing comprising the woven or knitted fabric according to  claim 7  in at least a portion of the clothing. 
     
     
         10 . Clothing comprising the woven or knitted fabric according to  claim 8  in at least a portion of the clothing.