| 摘要 |
PROBLEM TO BE SOLVED: To obtain a polyurethane elastic fiber having excellent yellowing resistance to NOX or light and useful for swimming wear by forming a polyurethane composition including a hindered amine compound or the like. SOLUTION: This fiber is obtained by forming a polyurethane composition including (A) preferably 1.0-3.0 wt.% hindered amine compound such as bis-(2,2,6,6-tetramethyl-4-piperidinyl) sebacate, (B) preferably 0.5-2.0 wt.% hydrazide-including compound such as N-phenyl-N-stearoylhydrazine and (C) 0.3-1.5 wt.% ultrabviolet light absorber such as 2,4-dihydroxybenzophenone. The polyurethane elastic fiber satisfies <=10 b-number as a cylindrical knit fabric after exposing to 200 ppm NOX atmosphere at 25 deg.C for 1.5 h as a cylindrical singly knit fabric and <=5 b-value after treating with a chlorine water of 10,000 ppm and pH 12 at 25 deg.C for 1 h when singly knitted as a cylindrical knit fabric. |
