Water-absorbing agent and method for producing the same

摘要

The present invention provides a water-absorbing agent that includes water-absorbent resin particles as essential components and is suitable for a sanitary material. A water-absorbing agent of the present invention includes water-absorbent resin particles obtained by polymerizing an unsaturated monomer having an acid group. The water-absorbing agent has centrifuge retention capacity (CRC) of 5 to 20 g/g and includes: a compound with a structure unit derived from polyalkyleneglycol other than the unsaturated monomer; and a multivalent metal salt, and accordingly the water-absorbing agent has high saline flow conductivity (SFC) in a range of the above centrifuge retention capacity (CRC).

主权项

1. A water-absorbing agent, comprising water-absorbent resin particles obtained by polymerizing an acid group-containing unsaturated monomer,
the water-absorbing agent having Centrifuge Retention Capacity (CRC) ranging from 5 to 20 g/g, and including (i) a compound that includes a constitutional unit derived from polyalkyleneglycol and that is other than an unsaturated monomer, said compound having a weight-average molecular weight ranging from 1000 to 6000 and (ii) polyvalent metal salt, and the compound including no radical polymerizable group, and being free without forming a chemical bond with the water-absorbent resin particles or being separable from the water-absorbent resin particles and without forming an internal crosslinked structure in the water-absorbent resin particles, the compound included in the water-absorbing agent falling within a range of 0.05 to 5 mass % with respect to the water-absorbing agent.