摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for efficiently producing a particle type water-absorbing resin having excellent physical properties at low cost while securing high productivity. Ž<P>SOLUTION: In the method for producing a water-absorbing resin, a process (1) for polymerizing a monomer aqueous solution, a process (2) for drying an obtained hydrous gel polymer, a process (3) for crushing a dried product or crushing and classifying the dried product for controlling grain size, and a process (5) for performing surface crosslinking on water-absorbing resin powder with controlled grain size are carried out successively. In the method, a process (4) for performing second heating and drying additionally on the water-absorbing resin powder with controlled grain size is also carried out before the process (5) for performing surface crosslinking. The water content (a loss on drying for 3 hours at 180°C) of the water-absorbing resin fed to the surface crosslinking process (5) is 0-3 wt.%. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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