Water absorbent matter and method for producing it as well as water absorbent and method for producing it

摘要

The present invention provides a water absorbent matter which is physically and chemically stable, difficult in shifting and falling-off of a water-absorbent resin particle and from a cellulose fiber, and thereby, has superior water-absorbent properties. A water absorbent matter like this is made by containing a water-absorbent resin particle having an acidic group such as a carboxyl group on the surface, a cellulose fiber, and a cationic high-molecular compound having a weight-average molecular weight of 2,000 or more, so that the water-absorbent resin particle is firmly set on the cellulose fiber by a cationic high-molecular compound in the presence of water. A water absorbent may be used, which is made by treating the surface of a water-absorbent resin particle having an acidic group with a crosslinking agent having two or more of a functional group capable of making a covalent bond by reacting with the acidic group to crosslink the particle at a part of the acidic group, and then, mixing the particle with a cationic high-molecular compound of an weight-average molecular weight 2,000 or more capable of making an ionic bond by reacting with the acidic group.