Patent ID: 8648161
Filing Date: 2014-02-11
Classification: C08F

Abstract:
1. A method for producing a polyacrylic acid (salt)-based water-absorbent resin, the method comprising: a preparation step in which a monomer is prepared from acrylic acid containing propionic acid; a polymerization step in which the monomer is polymerized; and a drying step in which the obtained hydrogel is dried, wherein Fe on the basis of Fe a plurality of acrylic acids having different propionic acid amounts of 1.1 to 50 times by mass with respect to the other acrylic acid are mixed to prepare the monomer; a plurality of acrylic acids obtained by different production processes of at least one selected from plant, installation site, raw material, oxide type, and refining type are mixed to prepare the monomer; and propionic acid is removed from polyacrylic acid (salt) during polymerization or after polymerization.