| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a water absorbent having excellent gel properties and showing excellent performance when used in a water-absorbing material of a sanitary/hygienic material such as paper diaper and a method of producing the same, and to provide a water absorbent which is a water absorbent resin having a high liquid holding property and high gel strength, which is safe and excellent in liquid permeability, and in which the amount of liquid permeability improver for improving the liquid permeability is reduced. <P>SOLUTION: In this method of producing a water absorbent having the main component of water-absorbing resin particles obtained by cross-linking and polymerizing a monomer having the main components of acrylic acid and/or its salt and by further surface cross-linking the resultant water-absorbing resin, the cross-linking polymerization is subjected to boiling polymerization in the presence of a water-soluble chain transfer agent ranging from 0.001 to 10 mol% with respect to the monomer, wherein the water-soluble chain transfer agent is selected from a group consisting of thiols, thiol acids, secondary alcohols, amines, phosphorous compounds, transition metal complexes, formic acid, and/or salts thereof. <P>COPYRIGHT: (C)2012,JPO&INPIT |
