| 摘要 |
Provided is a water absorbent resin that is useful to sanitary materials such as a disposable diaper, a sanitary napkin, and a blood absorbent for medical use each having a higher liquid permeability and a higher water absorbing speed. Further provided is a water absorbent resin powder that is useful to sanitary materials such as a disposable diaper, a sanitary napkin, and a blood absorbent for medical use each having increased in absorbency of a liquid and in heat retaining property. A gel grinding device (100) to be used to produce a water absorbent resin, includes: a screw (11); a feed opening (14); an extrusion opening (16); a porous plate (12); and a barrel (13), the barrel (13) including a return preventing member (19) provided on an inner surface thereof, and the return preventing member (19) satisfying at least one of specific parameters. |
