WATER-ABSORBING RESIN PRODUCTION METHOD

PROBLEM TO BE SOLVED: To provide a water-absorbing resin production method capable of efficiently obtaining a water-absorbing resin whose surface is subjected to surface crosslinking and excellent in physical properties, at low cost while securing high productivity.SOLUTION: The water-absorbing resin production method comprises steps of: adding a surface crosslinking agent and water to a polyacrylic acid salt-based water-absorbing resin in a mixer; and making the water-absorbing resin mixture taken out from the mixer react with the surface crosslinking agent by heating or by active energy ray irradiation in a reaction machine, the steps are performed sequentially. Part or whole of the water addition in the mixer is performed by adding water vapor. 【課題】物性に優れた、表面架橋された吸水性樹脂を、低コストで高い生産性を確保しながら効率的に得ることができる吸水性樹脂の製造方法を提供する。【解決手段】ポリアクリル酸塩系吸水性樹脂に表面架橋剤および水を混合機中で添加する工程、混合機から取り出した吸水性樹脂混合物を反応機中で加熱または活性エネルギー線照射で表面架橋剤と反応させる工程を順次含む、表面架橋された吸水性樹脂の製造方法であって、混合機中での水の添加の一部または全部を水蒸気で添加する製造方法。【選択図】なし