[Problem]To obtain a
fiber-treating agent and
polyester staple fibers having excellent processability during the
processing of
polyester staple fibers with high-pressure water-jets, and excellent
nonwoven fabric hydrophilicity after the high-pressure water-jet process. [Means of Solution]The present invention provides a
fiber-treating agent comprising a component A, which is a
polyester compound produced by carrying out a condensation
polymerization of an alkylene glycol, a polyalkylene glycol, and at least one member selected from the group consisting of aromatic dicarboxylic acids, C4-22 aliphatic dicarboxylic acids, and their ester-forming derivatives; a component B, which is a polyester compound produced by carrying out a condensation
polymerization of a polyoxyalkylene monol, an alkylene glycol, and at least one member selected from the group consisting of aromatic dicarboxylic acids and their ester-forming derivatives; and a component C, which is a C4-6
alkyl phosphate salt; and is characterized by components A, B, and C being blended in specific ratios. Also provided are polyester staple fibers treated with the treating agent, and a
nonwoven fabric manufactured by
processing the polyester staple fibers with high-pressure water jets.