Process for preparing water absorbent resin with high performance

A process for preparing a water absorbent resin, comprising the steps of:

• (a) coarse pulverizing a gel-type resin while internal cross-linking and polymerizing the gel-type resin from an aqueous solution of a partially neutralized acrylic acid-based monomer having an acid group, in the presence of a first cross-linking agent, so as to form a coarse pulverized gel-type resin having the size of 3 to 150 mm;
• (b) fine pulverizing the coarse pulverized gel-type resin so as to prepare a fine gel-type resin having the size of 1 to 20 mm;
• (c) drying the fine gel-type resin;
• (d) milling the dried fine gel-type resin and fractionating the same so as to prepare a base resin powder comprising particles having the size of 100 to 850 μm in an amount of 70 weight % or more;
• and
• (e) surface cross-linking the base resin powder with a second cross-linking agent so as to prepare the water absorbent resin.