Bulky spun yarn and a method for manufacturing the same from a combination of thermally extensible and thermally shrinkable fibers

Abstract

A double layered yarn having a sheath and core structure is prepared through a roving process, drawing process or fine spinning process. The sheath portion of the yarn is composed of staple fibers which have a high thermal shrinkage in boiling water of at least 5%, and the blended fiber ratio of which is between 50% and 25%. The core portion of the yarn is composed of staple fibers which have a property being spontaneously extensible, and the blended fiber ratio of which is between 25% and 75%. The double layered yarn is subjected to a heat treatment in hot water, and a bulky spun yarn which comprises staple fibers A and B is obtained. The staple fibers A are concentrated toward the inside of the bulky spun yarn after they are shrunk. The ends of staple fibers B are held within the inside of the bulky spun yarn, and the intermediate portions of fibers B are bulged as a loop from the body portion of the bulky spun yarn, after the fibers B are spontaneously extended.

Dependencies are inferred from the claim text.