SYNTHETIC-FIBER TREATMENT AGENT AND USE THEREOF

摘要

Provided are: a synthetic-fiber treatment agent which is used in the production of a synthetic fiber, which can reduce roll staining, and which is excellent in heat resistance; a method for producing synthetic-fiber filament yarn using the treatment agent; and a fibrous structure including the synthetic-fiber filament yarn obtained by the production method. The synthetic-fiber treatment agent contains a smoothing component (A) and a nonionic surfactant component (B), wherein the component (A) includes an ester compound (A2) having a structure in which a fatty acid and a multivalent aliphatic alcohol form an ester bond, and the contained amount of metals (excluding alkali metals) detected in nonvolatile components of the treatment agent by ICP emission spectrometry is 50 ppm or less.