abstract |
(57) [Problem] To provide a method for preventing coloring of a water-absorbing resin which can prevent coloring even when left under high temperature and high humidity for a long period of time. An aminocarboxylic acid-based metal chelating agent is added to at least one of the steps of a process for producing a water-absorbent resin containing an unsaturated carboxylic acid as an essential monomer or to the water-absorbent resin after the production. A method for preventing coloring of a water-absorbent resin, and a process for producing a water-absorbent resin containing an unsaturated carboxylic acid as an essential monomer, and water absorption in at least one of the steps or after the production. A method for using an aminocarboxylic acid-based metal chelating agent for preventing coloring of a water-absorbing resin obtained, comprising adding an aminocarboxylic acid-based metal chelating agent to a resin. |