Process for producing cationic dyeable polyester spontaneous elongation filament yarn, and method for manufacturing a fabric using a filament yarn obtained by the process

摘要

PROBLEM TO BE SOLVED: To stably obtain the subject filament yarn that is cationic dye-dyeable and reveals spontaneous stretchability in the following process by extruding a polyethylene terephthalate containing 5-sodio-sulfoisophthalic acid into fiber under specific conditions. ;SOLUTION: A polyester copolymer that comprises ethylene terephthalate as main recurring units and 1.5-3.5mol% of 5-sodiosulfoisophthalic acid as a copolymerization component is melt-extruded into high-orientation undrawn yarn with an optical birefringence (Δn) of 35×10^-3-55×10^-3 and a boiling water shrinkage of ≥40%. The undrawn yarn is drawn at a draw ratio of 0.4M-0.5M (M is the maximum draw ratio measured at preheating temperature of 85-90°C and M2.5) to form thick and thin filament yarn, then drawn at a draw ratio of ≤1.1 where the surface temperature (HR₂) of the take-up roller in the drawing zone is T_g+10°C or higher and does not exceed the surface temperature of the take-up roller in the first drawing roller). Further, the drawn yarn is thermally relaxed more than 10% (at H₂+50°C or higher).;COPYRIGHT: (C)1998,JPO