| abstract |
A process for the production of a water absorbent powder which comprises adding a nucleophile to a water absorbent powder made from a carboxylated resin, which is cross-linked with an epoxy crooslinking agent in the neighborhood of the surface and contains a residual cross-linking agent, in a heated state to thereby reduce the content of the residual cross-linking agent in the powder. The above process characterized by reducing the content of the residual cross-linking agent in the powder by adding a nucleophile to the powder in a heated state can constantly give a novel water absorbent powder satisfying all of the three requirements, i.e., an enhanced coefficient of water absorption under high pressure, a lowered content of residual cross-linking agent and an enhanced rate of absorption, as compared with the water absorbent resins of prior art which are cross-linked in the neighborhood of the surfaces. The powder can be used particularly preferably for sanitary goods such as paper diaper, sanitary napkin and so on. |