| 摘要 |
PROBLEM TO BE SOLVED: To efficiently obtain a water-absorbing resin which does not contain coagulated particles and massive particles in the produced resin particle cake and has a low residual solvent content, by removing a solvent from a water-soluble resin particle suspension obtained by a suspension polymerization method. SOLUTION: This method for producing a water-absorbing resin comprises suspending the aqueous solution of a water-soluble monomer (preferably acrylic acid or its alkali metal salt) forming the water-absorbing resin in the presence of a dispersant, subjecting the suspended water-soluble monomer to a reversed phase suspension polymerization in the presence of a water-soluble radical polymerization initiator to obtain the water-absorbing resin particles containing particles having particle diameters of <=100μm in an amount of <=1 wt.%, and then removing the solvent from the obtained water-absorbing resin particle suspension by the use of a solid-liquid separating machine to obtain the cake of the water-absorbing resin particles. The dispersant is preferably a compound of the formula [R is an 8 to 30C alkyl or alkylaryl; M is H or an alkali metal; (n) is 1 to 30; (m) is 1 to 3].
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