Schmeiser, Olsen & Watts
Easy dyeable polyester fiber
 Disclosed is an easy dyeable polyester fiber. Consisting of 60-95 mol % of polyethylene terephthalate and 5-40 mol % of polytrimethylene terephthalate, the polyester fiber of the present invention is prepared through copolymerization or through the ester interchange in such a way that it ranges, in melting point from 230.degree. C. to 250.degree. C., in birefringence from 100 to 190.times.10.sup.-3, and in boil-water shrinkage, from 8 to 25. Using disperse dyes, the polyester fiber can be dyed in deep shades at as low as or lower than 100.degree. C. under atmospheric pressure. Thus, the polyester fiber of the present invention is can be used in mixture with thermal resistance-insufficient fibers such as spandex without causing yellowing therein. Also, it does not allow spots in the dyeing to appear thereon upon after-treatment, and in addition shows good fastness to washing, water, sublimation and friction. 
Hyosung Corporation
Y D C Y
Y10T D01F C08G Y10T
additional inventional inventional additional
Hyoung-Jao Jung-Min Yang-kuk
Lee Kim Son