Absorbent material, water absorbent and method for producing water absorbent

Abstract

Provided are: a water-absorbing agent achieving, in a balanced manner, both good physical properties and a decrease in speed of coloration with lapse of time even if the water-absorbing agent has a high moisture absorbing speed due to having a large specific surface area; and an absorbent body having a low ratio of pulp and achieving, in a balanced manner, both good physical properties suitable for a thin disposable diaper and a decrease in speed of coloration with lapse of time. The absorbent body contains a hydrophilic base material and a water-absorbing agent which contains: surface-crosslinked water-absorbing resin particles having a non-uniformly pulverized shape; α-hydroxycarboxylic acid (salt); and an aminocarboxylic acid-based chelating agent and/or a phosphorus-based chelating agent, a point plotted along an x-axis that represents an amount (xmol %) of α-hydroxycarboxylic acid (salt) extracted from the water-absorbing agent and along a y-axis that represents an amount (ymmol %) of an aminocarboxylic acid-based chelating agent and/or a phosphorus-based chelating agent extracted from the water-absorbing agent being within a range that satisfies a specific relational formula of xand y, the water-absorbing agent having a moisture absorbing speed of 120 mg/g/hr or more at a temperature of 40±1° C. at a relative humidity of 75±1% RH.