| abstract |
(57) [Problem] To provide a polyamide synthetic fiber with lubricity, By imparting properties such as convergence and antistatic properties, smooth processes such as spinning, drawing and warping, knitting, weaving, etc. are performed to obtain high-quality fiber products and polyamide-based products. An object of the present invention is to provide a polyamide synthetic fiber treating agent that prevents yellowing of a greige obtained from synthetic fibers during heat setting and prevents the occurrence of staining spots due to the yellowing, and a method for using the same. SOLUTION: The treating agent for a polyamide-based synthetic fiber of the present invention comprises: (1) a specific imidazoline-based amphoteric surfactant in a pure agent in a treating agent comprising a lubricant and a surfactant; And (2) a hindered phenolic antioxidant in a pure content of 0.2 to 2.0% by weight, and preferably (3) a phosphate salt in a pure content. 1 to 10% by weight and / or (4) 2 to 10% by weight of thiodipropionic acid diester in pure content. |