Treatment agent for short fibers, aqueous solution for treatment agent for short fibers, treatment method for short fibers, production method for short fibers, and short fibers

A short fiber treatment agent for treating a short fiber, being substantially free of an organic phosphoric acid ester compound and comprising a fatty acid (A) and a nonionic surfactant (B), wherein

• if the sum of the contents of the fatty acid (A) and the nonionic surfactant (B) in the short fiber treatment agent is taken as 100 parts by mass, the short fiber treatment agent contains the fatty acid (A) at a ratio of not less than 0.001 parts by mass and not more than 10 parts by mass and the nonionic surfactant (B) at a ratio of not less than 90 parts by mass and not more than 99.999 parts by mass,
• a nonionic surfactant (B1) is contained in an amount of at least 50% by mass or more based on the total mass of the nonionic surfactant (B),
• the fatty acid (A) is at least one selected from the group consisting of a fatty acid with 1 to 6 carbon atoms, a hydroxy fatty acid with 1 to 6 carbon atoms, and a salt thereof, and
• the nonionic surfactant (B1) is a compound in which an alkylene oxide with 2 to 4 carbon atoms is added at a ratio of 3 to 30 moles with respect to 1 mole of a monohydric or dihydric alcohol.