Method of dyeing polypropylene terephthalate system containing fiber structure

摘要

PROBLEM TO BE SOLVED: To enable a polypropylene terephthalate-based fiber-containing fiber structure to be clearly dyed without causing the dirt in the dyeing machine and the unevenness of dyeing while suppressing the amount of a surface oligomer to a small amount by dyeing the fiber structure at an alkali side. SOLUTION: A fiber structure such as a woven fabric or the like including =20 wt.% polypropylene terephthalate-based fiber comprising a latently crimpable conjugate fiber such as the one of side-by-side type, or a partially oriented undrawn fiber is subjected to exhaustion dyeing in a dye bath at an alkali side within the range of pH 8.5-10, preferably 8.5-9.5 under an applied pressure at 100-120 deg.C to provide the objective dyed polypropylene terephthalate- based fiber-containing fiber structure having 600 ppm, preferably =300 ppm amount of surface oligomers.